Powered by Deep Web Technologies
Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines  

E-Print Network [OSTI]

Turbines by Michael Robert Shives B.Eng., Carleton University, 2008 A Thesis Submitted in Partial Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines examines methods for designing and analyzing kinetic turbines based on blade element momentum (BEM) theory

Victoria, University of

2

Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines  

E-Print Network [OSTI]

Turbines by Michael Robert Shives B.Eng., Carleton University, 2008 A Dissertation Submitted in Partial Hydrodynamic Modeling, Optimization and Performance Assessment for Ducted and Non-ducted Tidal Turbines) #12;iii ABSTRACT This thesis examines methods for designing and analyzing kinetic turbines based

Pedersen, Tom

3

Viscoelastic Models of Tidally Heated Exomoons  

E-Print Network [OSTI]

Tidal heating of exomoons may play a key role in their habitability, since the elevated temperature can melt the ice on the body even without significant solar radiation. The possibility of life is intensely studied on Solar System moons such as Europa or Enceladus, where the surface ice layer covers tidally heated water ocean. Tidal forces may be even stronger in extrasolar systems, depending on the properties of the moon and its orbit. For studying the tidally heated surface temperature of exomoons, we used a viscoelastic model for the first time. This model is more realistic than the widely used, so-called fixed Q models, because it takes into account the temperature dependency of the tidal heat flux, and the melting of the inner material. With the use of this model we introduced the circumplanetary Tidal Temperate Zone (TTZ), that strongly depends on the orbital period of the moon, and less on its radius. We compared the results with the fixed Q model and investigated the statistical volume of the TTZ usi...

Dobos, Vera

2015-01-01T23:59:59.000Z

4

Modeling the Energy Output from an In-Stream Tidal Turbine Farm  

E-Print Network [OSTI]

Abstract—This paper is based on a recent paper presented in the 2007 IEEE SMC conference by the same authors [1], discussing an approach to predicting energy output from an instream tidal turbine farm. An in-stream tidal turbine is a device for harnessing energy from tidal currents in channels, and functions in a manner similar to a wind turbine. A group of such turbines distributed in a site is called an in-stream tidal turbine farm which is similar to a wind farm. Approaches to estimating energy output from wind farms cannot be fully transferred to study tidal farms, however, because of the complexities involved in modeling turbines underwater. In this paper, we intend to develop an approach for predicting energy output of an in-stream tidal turbine farm. The mathematical formulation and basic procedure for predicting power output of a stand-alone turbine 1 is presented, which includes several highly nonlinear terms. In order to facilitate the computation and utilize the formulation for predicting power output from a turbine farm, a simplified relationship between turbine distribution and turbine farm energy output is derived. A case study is then conducted by applying the numerical procedure to predict the energy output of the farms. Various scenarios are implemented according to the environmental conditions in Seymour Narrows, British Columbia, Canada. Additionally, energy cost results are presented as an extension. Index Terms—renewable energy, in-stream turbine, tidal current, tidal power, vertical axis turbine, farm system modeling, in-stream tidal turbine farm 1 A stand-alone turbine refers to a turbine around which there is no other turbine that might potentially affect the performance of this turbine.

Ye Li; Barbara J. Lence; Sander M. Calisal

5

Spatial motion of the Magellanic Clouds. Tidal models ruled out?  

E-Print Network [OSTI]

Recently, Kallivayalil et al. derived new values of the proper motion for the Large and Small Magellanic Clouds (LMC and SMC, respectively). The spatial velocities of both Clouds are unexpectedly higher than their previous values resulting from agreement between the available theoretical models of the Magellanic System and the observations of neutral hydrogen (HI) associated with the LMC and the SMC. Such proper motion estimates are likely to be at odds with the scenarios for creation of the large-scale structures in the Magellanic System suggested so far. We investigated this hypothesis for the pure tidal models, as they were the first ones devised to explain the evolution of the Magellanic System, and the tidal stripping is intrinsically involved in every model assuming the gravitational interaction. The parameter space for the Milky Way (MW)-LMC-SMC interaction was analyzed by a robust search algorithm (genetic algorithm) combined with a fast restricted N-body model of the interaction. Our method extended ...

Ruzicka, Adam; Palous, Jan

2008-01-01T23:59:59.000Z

6

Modeling In-stream Tidal Energy Extraction and Its Potential Environmental Impacts  

SciTech Connect (OSTI)

In recent years, there has been growing interest in harnessing in-stream tidal energy in response to concerns of increasing energy demand and to mitigate climate change impacts. While many studies have been conducted to assess and map tidal energy resources, efforts for quantifying the associated potential environmental impacts have been limited. This paper presents the development of a tidal turbine module within a three-dimensional unstructured-grid coastal ocean model and its application for assessing the potential environmental impacts associated with tidal energy extraction. The model is used to investigate in-stream tidal energy extraction and associated impacts on estuarine hydrodynamic and biological processes in a tidally dominant estuary. A series of numerical experiments with varying numbers and configurations of turbines installed in an idealized estuary were carried out to assess the changes in the hydrodynamics and biological processes due to tidal energy extraction. Model results indicated that a large number of turbines are required to extract the maximum tidal energy and cause significant reduction of the volume flux. Preliminary model results also indicate that extraction of tidal energy increases vertical mixing and decreases flushing rate in a stratified estuary. The tidal turbine model was applied to simulate tidal energy extraction in Puget Sound, a large fjord-like estuary in the Pacific Northwest coast.

Yang, Zhaoqing; Wang, Taiping; Copping, Andrea; Geerlofs, Simon H.

2014-09-30T23:59:59.000Z

7

Modeling the Effects of Tidal Energy Extraction on Estuarine Hydrodynamics in a Stratified Estuary  

SciTech Connect (OSTI)

A three-dimensional coastal ocean model with a tidal turbine module was used in this paper to study the effects of tidal energy extraction on temperature and salinity stratification and density driven two-layer estuarine circulation. Numerical experiments with various turbine array configurations were carried out to investigate the changes in tidally mean temperature, salinity and velocity profiles in an idealized stratified estuary that connects to coastal water through a narrow tidal channel. The model was driven by tides, river inflow and sea surface heat flux. To represent the realistic size of commercial tidal farms, model simulations were conducted based on a small percentage of the total number of turbines that would generate the maximum extractable energy in the system. Model results indicated that extraction of tidal energy will increase the vertical mixing and decrease the stratification in the estuary. Extraction of tidal energy has stronger impact on the tidally-averaged salinity, temperature and velocity in the surface layer than the bottom. Energy extraction also weakens the two-layer estuarine circulation, especially during neap tides when tidal mixing the weakest and energy extraction is the smallest. Model results also show that energy generation can be much more efficient with higher hub height with relatively small changes in stratification and two-layer estuarine circulation.

Yang, Zhaoqing; Wang, Taiping

2013-08-15T23:59:59.000Z

8

Modeling Tidal Stream Energy Extraction and its Effects on Transport Processes in a Tidal Channel and Bay System Using a Three-dimensional Coastal Ocean Model  

SciTech Connect (OSTI)

This paper presents a numerical modeling study for simulating in-stream tidal energy extraction and assessing its effects on the hydrodynamics and transport processes in a tidal channel and bay system connecting to coastal ocean. A marine and hydrokinetic (MHK) module was implemented in a three-dimensional (3-D) coastal ocean model using the momentum sink approach. The MHK model was validated with the analytical solutions for tidal channels under one-dimensional (1-D) conditions. Model simulations were further carried out to compare the momentum sink approach with the quadratic bottom friction approach. The effects of 3-D simulations on the vertical velocity profile, maximum extractable energy, and volume flux reduction across the channel were investigated through a series of numerical experiments. 3-D model results indicate that the volume flux reduction at the maximum extractable power predicted by the 1-D analytical model or two-dimensional (2-D) depth-averaged numerical model may be overestimated. Maximum extractable energy strongly depends on the turbine hub height in the water column, and which reaches a maximum when turbine hub height is located at mid-water depth. Far-field effects of tidal turbines on the flushing time of the tidal bay were also investigated. Model results demonstrate that tidal energy extraction has a greater effect on the flushing time than volume flux reduction, which could negatively affect the biogeochemical processes in estuarine and coastal waters that support primary productivity and higher forms of marine life.

Yang, Zhaoqing; Wang, Taiping; Copping, Andrea E.

2013-02-28T23:59:59.000Z

9

PHYSIOLOGICAL PERFORMANCE OF INTERTIDAL CORALLINE ALGAE DURING A SIMULATED TIDAL CYCLE1  

E-Print Network [OSTI]

PHYSIOLOGICAL PERFORMANCE OF INTERTIDAL CORALLINE ALGAE DURING A SIMULATED TIDAL CYCLE1 Rebecca J, Lobban and Harrison 1997, Helmuth and Hofmann 2001). During high tide, intertidal algae are underwater algae may be emerged and exposed to increased light stress, elevated air tem- peratures, and increased

Martone, Patrick T.

10

Tidal Downsizing model. II. Planet-metallicity correlations  

E-Print Network [OSTI]

Core Accretion (CA), the de-facto accepted theory of planet formation, requires formation of massive solid cores as a prerequisite for assembly of gas giant planets. The observed metallicity correlations of exoplanets are puzzling in the context of CA. While gas giant planets are found preferentially around metal-rich host stars, planets smaller than Neptune orbit hosts with a wide range of metallicities. We propose an alternative interpretation of these observations in the framework of a recently developed planet formation hypothesis called Tidal Downsizing (TD). We perform population synthesis calculations based on TD, and find that the connection between the populations of the gas giant and the smaller solid-core dominated planets is non linear and not even monotonic. While gas giant planets formed in the simulations in the inner few AU region follow a strong positive correlation with the host star metallicity, the smaller planets do not. The simulated population of these smaller planets shows a shallow pe...

Nayakshin, Sergei

2015-01-01T23:59:59.000Z

11

Analytical Model of Tidal Distortion and Dissipation for a Giant Planet with a Viscoelastic Core  

E-Print Network [OSTI]

We present analytical expressions for the tidal Love numbers of a giant planet with a solid core and a fluid envelope. We model the core as a uniform, incompressible, elastic solid, and the envelope as a non-viscous fluid satisfying the $n=1$ polytropic equation of state. We discuss how the Love numbers depend on the size, density, and shear modulus of the core. We then model the core as a viscoelastic Maxwell solid and compute the tidal dissipation rate in the planet as characterized by the imaginary part of the Love number $k_2$. Our results improve upon existing calculations based on planetary models with a solid core and a uniform ($n=0$) envelope. Our analytical expressions for the Love numbers can be applied to study tidal distortion and viscoelastic dissipation of giant planets with solid cores of various rheological properties, and our general method can be extended to study tidal distortion/dissipation of super-earths.

Storch, Natalia I

2015-01-01T23:59:59.000Z

12

A Modeling Study of the Potential Water Quality Impacts from In-Stream Tidal Energy Extraction  

SciTech Connect (OSTI)

To assess the effects of tidal energy extraction on water quality in a simplified estuarine system, which consists of a tidal bay connected to the coastal ocean through a narrow channel where energy is extracted using in-stream tidal turbines, a three-dimensional coastal ocean model with built-in tidal turbine and water quality modules was applied. The effects of tidal energy extraction on water quality were examined for two energy extraction scenarios as compared with the baseline condition. It was found, in general, that the environmental impacts associated with energy extraction depend highly on the amount of power extracted from the system. Model results indicate that, as a result of energy extraction from the channel, the competition between decreased flushing rates in the bay and increased vertical mixing in the channel directly affects water quality responses in the bay. The decreased flushing rates tend to cause a stronger but negative impact on water quality. On the other hand, the increase of vertical mixing could lead to higher bottom dissolved oxygen at times. As the first modeling effort directly aimed at examining the impacts of tidal energy extraction on estuarine water quality, this study demonstrates that numerical models can serve as a very useful tool for this purpose. However, more careful efforts are warranted to address system-specific environmental issues in real-world, complex estuarine systems.

Wang, Taiping; Yang, Zhaoqing; Copping, Andrea E.

2013-11-09T23:59:59.000Z

13

Modeling Tidal Streams in evolving dark matter halos  

E-Print Network [OSTI]

We explore whether stellar tidal streams can provide information on the secular, cosmological evolution of the Milky Way's gravitational potential and on the presence of subhalos. We carry out long-term (~t_hubble) N-body simulations of disrupting satellite galaxies in a semi-analytic Galaxy potential where the dark matter halo and the subhalos evolve according to a LCDM cosmogony. All simulations are constrained to end up with the same position and velocity at present. Our simulations account for: (i) the secular evolution of the host halo's mass, size and shape, (ii) the presence of subhalos and (iii) dynamical friction. We find that tidal stream particles respond adiabatically to the Galaxy growth so that, at present, the energy and angular momentum distribution is exclusively determined by the present Galaxy potential. In other words, all present-day observables can only constrain the present mass distribution of the Galaxy independent of its past evolution. We also show that, if the full phase-space distribution of a tidal stream is available, we can accurately determine (i) the present Galaxy's shape and (ii) the amount of mass loss from the stream's progenitor, even if this evolution spanned a cosmologically significant epoch.

Jorge Penarrubia; Andrew J. Benson; David Martinez-Delgado; Hans-Walter Rix

2005-12-20T23:59:59.000Z

14

Modeling of In-stream Tidal Energy Development and its Potential Effects in Tacoma Narrows, Washington, USA  

SciTech Connect (OSTI)

Understanding and providing proactive information on the potential for tidal energy projects to cause changes to the physical system and to key water quality constituents in tidal waters is a necessary and cost-effective means to avoid costly regulatory involvement and late stage surprises in the permitting process. This paper presents a modeling study for evaluating the tidal energy extraction and its potential impacts on the marine environment in a real world site - Tacoma Narrows of Puget Sound, Washington State, USA. An unstructured-grid coastal ocean model, fitted with a module that simulates tidal energy devices, was applied to simulate the tidal energy extracted by different turbine array configurations and the potential effects of the extraction at local and system-wide scales in Tacoma Narrows and South Puget Sound. Model results demonstrated the advantage of an unstructured-grid model for simulating the far-field effects of tidal energy extraction in a large model domain, as well as assessing the near-field effect using a fine grid resolution near the tidal turbines. The outcome shows that a realistic near-term deployment scenario extracts a very small fraction of the total tidal energy in the system and that system wide environmental effects are not likely; however, near-field effects on the flow field and bed shear stress in the area of tidal turbine farm are more likely. Model results also indicate that from a practical standpoint, hydrodynamic or water quality effects are not likely to be the limiting factor for development of large commercial-scale tidal farms. Results indicate that very high numbers of turbines are required to significantly alter the tidal system; limitations on marine space or other environmental concerns are likely to be reached before reaching these deployment levels. These findings show that important information obtained from numerical modeling can be used to inform regulatory and policy processes for tidal energy development.

Yang, Zhaoqing; Wang, Taiping; Copping, Andrea E.; Geerlofs, Simon H.

2014-10-01T23:59:59.000Z

15

A Conceptual Restoration Plan and Tidal Hydrology Assessment for Reconnecting Spring Branch Creek to Suisun Marsh, Solano County, California  

E-Print Network [OSTI]

tidal wetland below MHLW Table 4.19. Performance IndicatorsPerformance Indicator All Tidal wetlands Tidal wetlands All

Olson, Jessica J.

2012-01-01T23:59:59.000Z

16

Final Report for Sea-level Rise Response Modeling for San Francisco Bay Estuary Tidal  

E-Print Network [OSTI]

i Final Report for Sea-level Rise Response Modeling for San Francisco Bay Estuary Tidal Marshes Refuge in northern San Francisco Bay, California. #12;iii Final Report for Sea-level Rise Response)................................................................... 7 Sea-level rise scenario model inputs

Fleskes, Joe

17

A model-dye comparison experiment in the tidal mixing front zone on the southern flank of Georges Bank  

E-Print Network [OSTI]

A model-dye comparison experiment in the tidal mixing front zone on the southern flank of Georges; revised 8 June 2007; accepted 30 October 2007; published 9 February 2008. [1] A process-oriented model-dye the observed movement of dye across the tidal mixing front on the southern flank of Georges Bank during 22

Chen, Changsheng

18

Modeling the dynamics of tidally-interacting binary neutron stars up to merger  

E-Print Network [OSTI]

We propose an effective-one-body (EOB) model that describes the general relativistic dynamics of neutron star binaries from the early inspiral up to merger. Our EOB model incorporates an enhanced attractive tidal potential motivated by recent analytical advances in the post-Newtonian and gravitational self-force description of relativistic tidal interactions. No fitting parameters are introduced for the description of tidal interaction in the late, strong-field dynamics. We compare the model dynamics (described by the gauge invariant relation between binding energy and orbital angular momentum), and the gravitational wave phasing, with new high-resolution multi-orbit numerical relativity simulations of equal-mass configurations with different equations of state. We find agreement essentially within the uncertainty of the numerical data for all the configurations. Our model is the first semi-analytical model which captures the tidal amplification effects close to merger. It thereby provides the most accurate analytical representation of binary neutron star dynamics and waveforms currently available.

Sebastiano Bernuzzi; Alessandro Nagar; Tim Dietrich; Thibault Damour

2014-12-15T23:59:59.000Z

19

Modeling the dynamics of tidally-interacting binary neutron stars up to merger  

E-Print Network [OSTI]

The data analysis of the gravitational wave signals emitted by coalescing neutron star binaries requires the availability of an accurate analytical representation of the dynamics and waveforms of these systems. We propose an effective-one-body (EOB) model that describes the general relativistic dynamics of neutron star binaries from the early inspiral up to merger. Our EOB model incorporates an enhanced attractive tidal potential motivated by recent analytical advances in the post-Newtonian and gravitational self-force description of relativistic tidal interactions. No fitting parameters are introduced for the description of tidal interaction in the late, strong-field dynamics. We compare the model energetics and the gravitational wave phasing with new high-resolution multi-orbit numerical relativity simulations of equal-mass configurations with different equations of state. We find agreement within the uncertainty of the numerical data for all configurations. Our model is the first semi-analytical model which captures the tidal amplification effects close to merger. It thereby provides the most accurate analytical representation of binary neutron star dynamics and waveforms currently available.

Sebastiano Bernuzzi; Alessandro Nagar; Tim Dietrich; Thibault Damour

2015-02-18T23:59:59.000Z

20

A frequency domain finite element model for tidal circulation  

E-Print Network [OSTI]

A highly efficient finite element model has been developed for the numerical prediction of depth average circulation within small scale embayments which are often characterized by irregular boundaries and bottom topography.

Westerink, Joannes J.

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Substructure and Tidal Debris in Local Galaxies: Models and Observations  

E-Print Network [OSTI]

One of the generic predictions of modern cosmological models is that large galaxies should have experienced many mergers with smaller galaxies at some point in their past. Debris from such encounters will leave spatially distinct substructure in the stellar haloes of nearby galaxies, detectable for a few orbital periods after the final merger. In the case of the Milky Way, kinematic data from surveys such as RAVE and satellite missions such as GAIA will allow us to probe much more of the merger history, and to connect the properties of the stellar halo with those of local dwarf galaxies. To estimate what these programmes may discover, we review current observations of minor mergers in nearby galaxies, and compare these with predictions from a semi-analytic model of galaxy formation.

James E. Taylor

2004-11-18T23:59:59.000Z

22

IR DIAL performance modeling  

SciTech Connect (OSTI)

We are developing a DIAL performance model for CALIOPE at LLNL. The intent of the model is to provide quick and interactive parameter sensitivity calculations with immediate graphical output. A brief overview of the features of the performance model is given, along with an example of performance calculations for a non-CALIOPE application.

Sharlemann, E.T.

1994-07-01T23:59:59.000Z

23

Exploration applications of a transgressive tidal flats model to Mississippian Midale carbonates, eastern Williston Basin  

SciTech Connect (OSTI)

Midale (Mississippian) production was first established in 1953 in Saskatchewan, Canada. The unit was initially defined in the subsurface as the carbonate interval between the top of the Frobisher Anhydrite and the base of the Midale Anhydrite. That nomenclature is used in this report. During 1953, Midale production was found in the United States portion of the Williston basin in Bottineau County, North Dakota. Later exploration extended Midale production westward into Burke County, North Dakota. Cumulative production from the Midale is approximately 660 million bbl, of which 640 million bbl are from Canadian fields. Initially, hydrocarbon entrapment in the Midale was believed to be controlled by the Mississippian subcrop, with the Burke County production controlled by low-relief structural closure. Petrographic examination of cores and cuttings from the Midale in both Saskatchewan, Canada, and Burke and Bottineau Counties, North Dakota, indicates that production is controlled by facies changes within the unit. Stratigraphic traps are formed by the lateral and vertical changes from grain-supported facies deposited in tidal channel, subtidal bar, or beach settings; seals are formed by mud-rich sediments. Use of a transgressive carbonate tidal flats model best explains current production patterns and indicates substantial potential for additional production in eastern North Dakota and South Dakota.

Porter, L.A.; Reid, R.S.R.

1985-05-01T23:59:59.000Z

24

Exploration applications of a transgressive tidal-flats model to Mississippian Midale carbonates, eastern Williston Basin  

SciTech Connect (OSTI)

Midale (Mississippian) production was first indicated in 1953 in Saskatchewan, Canada. The unit was initially defined in the subsurface as the carbonate interval between the top of the Frobisher Anhydrite and the base of the Midale Anhydrite. This same nomenclature is used in this paper. In 1953, Midale production was found on the US side of the Williston basin in Bottineau County, North Dakota. Later exploration extended Midale production westward into Burke County, North Dakota, in 1955. Cumulative production from the Midale is approximately 660 million bbl with 640 million from the Canadian side of the Williston basin. Initially, hydrocarbon entrapment in the Midale was believed to be controlled by the Mississippian subcrop, with the Burke County production controlled by low-relief structural closure. Petrographic examination of cores and cuttings from the Midale in both Saskatchewan, Canada, and Burke and Bottineau Counties, North Dakota, indicates that production is controlled by facies changes within the unit. Stratigraphic traps are formed by the lateral and vertical changes from grain-supported facies deposited in tidal-channel, subtidal-bar, or beach settings; seals are formed by mud-rich sediments. Use of a transgressive carbonate tidal-flats model best explains current production patterns and indicates substantial potential for additional production in eastern North Dakota and South Dakota.

Porter, L.A.; Reid, F.S.

1985-02-01T23:59:59.000Z

25

Chaos and Tidal Capture  

E-Print Network [OSTI]

We review the tidal capture mechanism for binary formation, an important process in globular cluster cores and perhaps open cluster cores. Tidal capture binaries may be the precursors for some of the low-mass X-ray binaries observed in abundance in globular clusters. They may also play an important role in globular cluster dynamics. We summarize the chaos model for tidal interaction (Mardling 1995, ApJ, 450, 722, 732), and discuss how this affects our understanding of the circularization process which follows capture.

Rosemary A. Mardling

1995-12-07T23:59:59.000Z

26

A comparison of measured and modeled tidal currents in the Gulf of Maine  

E-Print Network [OSTI]

to the persistence of the clockwise circulation around the Bank (Garrett er al. , 1978). Loder (1980) has shown theoretically that rectification of the strong semidiurnal tidal current across the steeply sloping northern edge of Georges Bank can produce a... astronomical forcing (Garrett, 1972; Brown and Moody, 1987). Garrett (1972) estimated the natural period of the Gulf of Maine-Bay of Fundy basin to be 13. 3M. 4 hours, which is near the frequency of the semidiurnal tidal constituents. Since the M2 semidiurnal...

Cook, Michael S

1990-01-01T23:59:59.000Z

27

A Low-order Model of Water Vapor, Clouds, and Thermal Emission for Tidally Locked Terrestrial Planets  

E-Print Network [OSTI]

In the spirit of minimal modeling of complex systems, we develop an idealized two-column model to investigate the climate of tidally locked terrestrial planets with Earth-like atmospheres in the habitable zone of M-dwarf stars. The model is able to approximate the fundamental features of the climate obtained from three-dimensional (3D) atmospheric general circulation model (GCM) simulations. One important reason for the two-column model's success is that it reproduces the high cloud albedo of the GCM simulations, which reduces the planet's temperature and delays the onset of a runaway greenhouse state. The two-column model also clearly illustrates a secondary mechanism for determining the climate: the nightside acts as a ``radiator fin'' through which infrared energy can be lost to space easily. This radiator fin is maintained by a temperature inversion and dry air on the nightside, and plays a similar role to the subtropics on modern Earth. Since 1D radiative-convective models cannot capture the effects of t...

Yang, Jun

2014-01-01T23:59:59.000Z

28

Tidal interactions in multi-planet systems  

E-Print Network [OSTI]

We study systems of close orbiting planets evolving under the influence of tidal circularization. It is supposed that a commensurability forms through the action of disk induced migration and orbital circularization. After the system enters an inner cavity or the disk disperses the evolution continues under the influence of tides due to the central star which induce orbital circularization. We derive approximate analytic models that describe the evolution away from a general first order resonance that results from tidal circularization in a two planet system and which can be shown to be a direct consequence of the conservation of energy and angular momentum. We consider the situation when the system is initially very close to resonance and also when the system is between resonances. We also perform numerical simulations which confirm these models and then apply them to two and four planet systems chosen to have parameters related to the GJ581 and HD10180 systems. We also estimate the tidal dissipation rates t...

Papaloizou, J C B

2011-01-01T23:59:59.000Z

29

Accelerating Energy Savings Performance Contracting Through Model...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Accelerating Energy Savings Performance Contracting Through Model Statewide Programs Accelerating Energy Savings Performance Contracting Through Model Statewide Programs Provides...

30

2014 PV Performance Modeling Workshop  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2014 PV Performance Modeling Workshop Photo courtesy of Sempra Energy 8:00 AM to 9:00 PM Monday, May 5, 2014 At Biltmore Hotel, Santa Clara, California 512014 Agenda: Start Time...

31

Tidal Energy Research  

SciTech Connect (OSTI)

This technical report contains results on the following topics: 1) Testing and analysis of sub-scale hydro-kinetic turbines in a flume, including the design and fabrication of the instrumented turbines. 2) Field measurements and analysis of the tidal energy resource and at a site in northern Puget Sound, that is being examined for turbine installation. 3) Conceptual design and performance analysis of hydro-kinetic turbines operating at high blockage ratio, for use for power generation and flow control in open channel flows.

Stelzenmuller, Nickolas [Univ of Washington; Aliseda, Alberto [Univ of Washington; Palodichuk, Michael [Univ of Washington; Polagye, Brian [Univ of Washington; Thomson, James [Univ of Washington; Chime, Arshiya [Univ of Washington; Malte, Philip [Univ of washington

2014-03-31T23:59:59.000Z

32

Air Conditioner Compressor Performance Model  

SciTech Connect (OSTI)

During the past three years, the Western Electricity Coordinating Council (WECC) Load Modeling Task Force (LMTF) has led the effort to develop the new modeling approach. As part of this effort, the Bonneville Power Administration (BPA), Southern California Edison (SCE), and Electric Power Research Institute (EPRI) Solutions tested 27 residential air-conditioning units to assess their response to delayed voltage recovery transients. After completing these tests, different modeling approaches were proposed, among them a performance modeling approach that proved to be one of the three favored for its simplicity and ability to recreate different SVR events satisfactorily. Funded by the California Energy Commission (CEC) under its load modeling project, researchers at Pacific Northwest National Laboratory (PNNL) led the follow-on task to analyze the motor testing data to derive the parameters needed to develop a performance models for the single-phase air-conditioning (SPAC) unit. To derive the performance model, PNNL researchers first used the motor voltage and frequency ramping test data to obtain the real (P) and reactive (Q) power versus voltage (V) and frequency (f) curves. Then, curve fitting was used to develop the P-V, Q-V, P-f, and Q-f relationships for motor running and stalling states. The resulting performance model ignores the dynamic response of the air-conditioning motor. Because the inertia of the air-conditioning motor is very small (H<0.05), the motor reaches from one steady state to another in a few cycles. So, the performance model is a fair representation of the motor behaviors in both running and stalling states.

Lu, Ning; Xie, YuLong; Huang, Zhenyu

2008-09-05T23:59:59.000Z

33

TEA - a linear frequency domain finite element model for tidal embayment analysis  

E-Print Network [OSTI]

A frequency domain (harmonic) finite element model is developed for the numerical prediction of depth average circulation within small embayments. Such embayments are often characterized by irregular boundaries and bottom ...

Westerink, Joannes J.

1984-01-01T23:59:59.000Z

34

Tidal heating and tidal evolution in the solar system  

E-Print Network [OSTI]

In this thesis, we examine the effects of tidal dissipation on solid bodies in application and in theory. First, we study the effects of tidal heating and tidal evolution in the Saturnian satellite system. We constrain the ...

Meyer, Jennifer Ann

2011-01-01T23:59:59.000Z

35

Tidal Wetlands Regulations (Connecticut)  

Broader source: Energy.gov [DOE]

Most activities occurring in or near tidal wetlands are regulated, and this section contains information on such activities and required permit applications for proposed activities. Applications...

36

Tidal Heating of Extra-Solar Planets  

E-Print Network [OSTI]

Extra-solar planets close to their host stars have likely undergone significant tidal evolution since the time of their formation. Tides probably dominated their orbital evolution once the dust and gas had cleared away, and as the orbits evolved there was substantial tidal heating within the planets. The tidal heating history of each planet may have contributed significantly to the thermal budget that governed the planet's physical properties, including its radius, which in many cases may be measured by observing transit events. Typically, tidal heating increases as a planet moves inward toward its star and then decreases as its orbit circularizes. Here we compute the plausible heating histories for several planets with measured radii, using the same tidal parameters for the star and planet that had been shown to reconcile the eccentricity distribution of close-in planets with other extra-solar planets. Several planets are discussed, including for example HD 209458 b, which may have undergone substantial tidal heating during the past billion years, perhaps enough to explain its large measured radius. Our models also show that GJ 876 d may have experienced tremendous heating and is probably not a solid, rocky planet. Theoretical models should include the role of tidal heating, which is large, but time-varying.

Brian Jackson; Richard Greenberg; Rory Barnes

2008-02-29T23:59:59.000Z

37

Clarence Strait Tidal Energy Project, Tenax Energy Tropical Tidal...  

Open Energy Info (EERE)

Test Centre, Jump to: navigation, search 1 Retrieved from "http:en.openei.orgwindex.php?titleClarenceStraitTidalEnergyProject,TenaxEnergyTropicalTidalTestCentre,&o...

38

Predicting Improved Chiller Performance Through Thermodynamic Modeling  

E-Print Network [OSTI]

This paper presents two case studies in which thermodynamic modeling was used to predict improved chiller performance. The model predicted the performance (COP and total energy consumption) of water-cooled centrifugal chillers as a function...

Figueroa, I. E.; Cathey, M.; Medina, M. A.; Nutter, D. W.

39

Development and Verification of a Computational Fluid Dynamics Model of a Horizontal-Axis Tidal Current Turbine  

SciTech Connect (OSTI)

This paper describes the development of a computational fluid dynamics (CFD) methodology to simulate the hydrodynamics of horizontal-axis tidal current turbines. Qualitative measures of the CFD solutions were independent of the grid resolution. Conversely, quantitative comparisons of the results indicated that the use of coarse computational grids results in an under prediction of the hydrodynamic forces on the turbine blade in comparison to the forces predicted using more resolved grids. For the turbine operating conditions considered in this study, the effect of the computational timestep on the CFD solution was found to be minimal, and the results from steady and transient simulations were in good agreement. Additionally, the CFD results were compared to corresponding blade element momentum method calculations and reasonable agreement was shown. Nevertheless, we expect that for other turbine operating conditions, where the flow over the blade is separated, transient simulations will be required.

Lawson, M. J.; Li, Y.; Sale, D. C.

2011-10-01T23:59:59.000Z

40

Statistical Performance Modeling of SRAMs  

E-Print Network [OSTI]

Yield analysis is a critical step in memory designs considering a variety of performance constraints. Traditional circuit level Monte-Carlo simulations for yield estimation of Static Random Access Memory (SRAM) cell is quite time consuming due...

Zhao, Chang

2011-02-22T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

ASSESSMENT OF ECONOMIC PERFORMANCE OF MODEL PREDICTIVE  

E-Print Network [OSTI]

ASSESSMENT OF ECONOMIC PERFORMANCE OF MODEL PREDICTIVE CONTROL THROUGH VARIANCE/CONSTRAINT TUNING advanced process control (APC) strategies to deal with multivariable constrained control problems with an ultimate objective towards economic optimization. Any attempt to evaluate MPC performance should therefore

Huang, Biao

42

THE INFLUENCE OF ORBITAL ECCENTRICITY ON TIDAL RADII OF STAR CLUSTERS  

SciTech Connect (OSTI)

We have performed N-body simulations of star clusters orbiting in a spherically symmetric smooth galactic potential. The model clusters cover a range of initial half-mass radii and orbital eccentricities in order to test the historical assumption that the tidal radius of a cluster is imposed at perigalacticon. The traditional assumption for globular clusters is that since the internal relaxation time is larger than its orbital period, the cluster is tidally stripped at perigalacticon. Instead, our simulations show that a cluster with an eccentric orbit does not need to fully relax in order to expand. After a perigalactic pass, a cluster recaptures previously unbound stars, and the tidal shock at perigalacticon has the effect of energizing inner region stars to larger orbits. Therefore, instead of the limiting radius being imposed at perigalacticon, it more nearly traces the instantaneous tidal radius of the cluster at any point in the orbit. We present a numerical correction factor to theoretical tidal radii calculated at perigalacticon which takes into consideration both the orbital eccentricity and current orbital phase of the cluster.

Webb, Jeremy J.; Harris, William E.; Sills, Alison [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)] [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada); Hurley, Jarrod R., E-mail: webbjj@mcmaster.ca [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, VIC 3122 (Australia)

2013-02-20T23:59:59.000Z

43

Sandia National Laboratories: PV Performance Modeling Collaborative  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

being pursued in this collaborative include: PVPMC Website: (http:pvpmc.org) Matlab(tm) PV Performance Modeling Toolbox (PVLIB Toolbox can be downloaded on http:...

44

Performance modeling in the design process  

SciTech Connect (OSTI)

Here, in capsule form, are some lessons learned trying to integrate performance modeling into the design process. Performance modeling should play a central role in system design; ignore it at your peril. The role of performance modeling is not the same in all design projects. Clearly specify performance goals and what factors will affect performance; they try to model those factors. Obtaining the data for the models can be a major problem; ongoing measurement projects are always worthwhile. Prototypes can be valuable data gathering tools if they are instrumented for this purpose. Anticipate the effect of environment on the system you are designing, and the effects of the system on the environment. Including the performance analyst on the design team from the beginning; if he is perceived as an outsider, he is more likely to be ignored, especially if decisions have already been made.

Alexander, W.; Brice, R.

1982-01-01T23:59:59.000Z

45

Tidal Capture of Stars by Intermediate-Mass Black Holes  

E-Print Network [OSTI]

Recent X-ray observations and theoretical modelling have made it plausible that some ultraluminous X-ray sources (ULX) are powered by intermediate-mass black holes (IMBHs). N-body simulations have also shown that runaway merging of stars in dense star clusters is a way to form IMBHs. In the present paper we have performed N-body simulations of young clusters such as MGG-11 of M82 in which IMBHs form through runaway merging. We took into account the effect of tidal heating of stars by the IMBH to study the tidal capture and disruption of stars by IMBHs. Our results show that the IMBHs have a high chance of capturing stars through tidal heating within a few core relaxation times and we find that 1/3 of all runs contain a ULX within the age limits of MGG-11, a result consistent with the fact that a ULX is found in this galaxy. Our results strengthen the case for some ULX being powered by intermediate-mass black holes.

H. Baumgardt; C. Hopman; S. Portegies Zwart; J. Makino

2005-11-27T23:59:59.000Z

46

Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition  

SciTech Connect (OSTI)

Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. The technology used to harvest energy from tidal current is called a tidal current turbine. Though some of the principles of wind turbine design are applicable to tidal current turbines, the design of latter ones need additional considerations like cavitation damage, corrosion etc. for the long-term reliability of such turbines. Depending up on the orientation of axis, tidal current turbines can be classified as vertical axis turbines or horizontal axis turbines. Existing studies on the vertical axis tidal current turbine focus more on the hydrodynamic aspects of the turbine rather than the structural aspects. This paper summarizes our recent efforts to study the integrated hydrodynamic and structural aspects of the vertical axis tidal current turbines. After reviewing existing methods in modeling tidal current turbines, we developed a hybrid approach that combines discrete vortex method -finite element method that can simulate the integrated hydrodynamic and structural response of a vertical axis turbine. This hybrid method was initially employed to analyze a typical three-blade vertical axis turbine. The power coefficient was used to evaluate the hydrodynamic performance, and critical deflection was considered to evaluate the structural reliability. A sensitivity analysis was also conducted with various turbine height-to-radius ratios. The results indicate that both the power output and failure probability increase with the turbine height, suggesting a necessity for optimal design. An attempt to optimize a 3-blade vertical axis turbine design with hybrid method yielded a ratio of turbine height to radius (H/R) about 3.0 for reliable maximum power output.

Li, Ye; Karri, Naveen K.; Wang, Qi

2014-04-30T23:59:59.000Z

47

On the statistical stability of the M2 barotropic and baroclinic tidal characteristics from along-track TOPEX//Poseidon  

E-Print Network [OSTI]

with internal tidal wave activity and for those who assimilate altimetric data in their models by giving-track TOPEX//Poseidon satellite altimetry analysis Loren Carre`re, Christian Le Provost, and Florent Lyard. [1] An along-track analysis of 7 years of TOPEX/Poseidon (T/P) data has been performed on the global

48

Generic CSP Performance Model for NREL's System Advisor Model: Preprint  

SciTech Connect (OSTI)

The suite of concentrating solar power (CSP) modeling tools in NREL's System Advisor Model (SAM) includes technology performance models for parabolic troughs, power towers, and dish-Stirling systems. Each model provides the user with unique capabilities that are catered to typical design considerations seen in each technology. Since the scope of the various models is generally limited to common plant configurations, new CSP technologies, component geometries, and subsystem combinations can be difficult to model directly in the existing SAM technology models. To overcome the limitations imposed by representative CSP technology models, NREL has developed a 'Generic Solar System' (GSS) performance model for use in SAM. This paper discusses the formulation and performance considerations included in this model and verifies the model by comparing its results with more detailed models.

Wagner, M. J.; Zhu, G.

2011-08-01T23:59:59.000Z

49

Modeling well performance in compartmentalized gas reservoirs  

E-Print Network [OSTI]

Predicting the performance of wells in compartmentalized reservoirs can be quite challenging to most conventional reservoir engineering tools. The purpose of this research is to develop a Compartmentalized Gas Depletion Model that applies not only...

Yusuf, Nurudeen

2008-10-10T23:59:59.000Z

50

Modeling well performance in compartmentalized gas reservoirs  

E-Print Network [OSTI]

Predicting the performance of wells in compartmentalized reservoirs can be quite challenging to most conventional reservoir engineering tools. The purpose of this research is to develop a Compartmentalized Gas Depletion Model that applies not only...

Yusuf, Nurudeen

2009-05-15T23:59:59.000Z

51

Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, Alaska FINAL REPORT  

SciTech Connect (OSTI)

The Aleutian Pribilof Islands Association was awarded a U.S. Department of Energy Tribal Energy Program grant (DE-EE0005624) for the Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, Alaska (Project). The goal of the Project was to perform a feasibility study to determine if a tidal energy project would be a viable means to generate electricity and heat to meet long-term fossil fuel use reduction goals, specifically to produce at least 30% of the electrical and heating needs of the tribally-owned buildings in False Pass. The Project Team included the Aleut Region organizations comprised of the Aleutian Pribilof Island Association (APIA), and Aleutian Pribilof Island Community Development Association (APICDA); the University of Alaska Anchorage, ORPC Alaska a wholly-owned subsidiary of Ocean Renewable Power Company (ORPC), City of False Pass, Benthic GeoScience, and the National Renewable Energy Laboratory (NREL). The following Project objectives were completed: collected existing bathymetric, tidal, and ocean current data to develop a basic model of current circulation at False Pass, measured current velocities at two sites for a full lunar cycle to establish the viability of the current resource, collected data on transmission infrastructure, electrical loads, and electrical generation at False Pass, performed economic analysis based on current costs of energy and amount of energy anticipated from and costs associated with the tidal energy project conceptual design and scoped environmental issues. Utilizing circulation modeling, the Project Team identified two target sites with strong potential for robust tidal energy resources in Isanotski Strait and another nearer the City of False Pass. In addition, the Project Team completed a survey of the electrical infrastructure, which identified likely sites of interconnection and clarified required transmission distances from the tidal energy resources. Based on resource and electrical data, the Project Team developed a conceptual tidal energy project design utilizing ORPC’s TidGen® Power System. While the Project Team has not committed to ORPC technology for future development of a False Pass project, this conceptual design was critical to informing the Project’s economic analysis. The results showed that power from a tidal energy project could be provided to the City of False at a rate at or below the cost of diesel generated electricity and sold to commercial customers at rates competitive with current market rates, providing a stable, flat priced, environmentally sound alternative to the diesel generation currently utilized for energy in the community. The Project Team concluded that with additional grants and private investment a tidal energy project at False Pass is well-positioned to be the first tidal energy project to be developed in Alaska, and the first tidal energy project to be interconnected to an isolated micro grid in the world. A viable project will be a model for similar projects in coastal Alaska.

Wright, Bruce Albert [Aleutian Pribilof Islands Association] [Aleutian Pribilof Islands Association

2014-05-07T23:59:59.000Z

52

Low-Order Modelling of Blade-Induced Turbulence for RANS Actuator Disk Computations of Wind and Tidal Turbines  

E-Print Network [OSTI]

Modelling of turbine blade-induced turbulence (BIT) is discussed within the framework of three-dimensional Reynolds-averaged Navier-Stokes (RANS) actuator disk computations. We first propose a generic (baseline) BIT model, which is applied only to the actuator disk surface, does not include any model coefficients (other than those used in the original RANS turbulence model) and is expected to be valid in the limiting case where BIT is fully isotropic and in energy equilibrium. The baseline model is then combined with correction functions applied to the region behind the disk to account for the effect of rotor tip vortices causing a mismatch of Reynolds shear stress between short- and long-time averaged flow fields. Results are compared with wake measurements of a two-bladed wind turbine model of Medici and Alfredsson [Wind Energy, Vol. 9, 2006, pp. 219-236] to demonstrate the capability of the new model.

Nishino, Takafumi

2012-01-01T23:59:59.000Z

53

PV performance modeling workshop summary report.  

SciTech Connect (OSTI)

During the development of a solar photovoltaic (PV) energy project, predicting expected energy production from a system is a key part of understanding system value. System energy production is a function of the system design and location, the mounting configuration, the power conversion system, and the module technology, as well as the solar resource. Even if all other variables are held constant, annual energy yield (kWh/kWp) will vary among module technologies because of differences in response to low-light levels and temperature. A number of PV system performance models have been developed and are in use, but little has been published on validation of these models or the accuracy and uncertainty of their output. With support from the U.S. Department of Energy's Solar Energy Technologies Program, Sandia National Laboratories organized a PV Performance Modeling Workshop in Albuquerque, New Mexico, September 22-23, 2010. The workshop was intended to address the current state of PV system models, develop a path forward for establishing best practices on PV system performance modeling, and set the stage for standardization of testing and validation procedures for models and input parameters. This report summarizes discussions and presentations from the workshop, as well as examines opportunities for collaborative efforts to develop objective comparisons between models and across sites and applications.

Stein, Joshua S.; Tasca, Coryne Adelle (SRA International, Inc., Fairfax, VA); Cameron, Christopher P.

2011-05-01T23:59:59.000Z

54

A CLASS OF ECCENTRIC BINARIES WITH DYNAMIC TIDAL DISTORTIONS DISCOVERED WITH KEPLER  

SciTech Connect (OSTI)

We have discovered a class of eccentric binary systems within the Kepler data archive that have dynamic tidal distortions and tidally induced pulsations. Each has a uniquely shaped light curve that is characterized by periodic brightening or variability at timescales of 4-20 days, frequently accompanied by shorter period oscillations. We can explain the dominant features of the entire class with orbitally varying tidal forces that occur in close, eccentric binary systems. The large variety of light curve shapes arises from viewing systems at different angles. This hypothesis is supported by spectroscopic radial velocity measurements for five systems, each showing evidence of being in an eccentric binary system. Prior to the discovery of these 17 new systems, only four stars, where KOI-54 is the best example, were known to have evidence of these dynamic tides and tidally induced oscillations. We perform preliminary fits to the light curves and radial velocity data, present the overall properties of this class, and discuss the work required to accurately model these systems.

Thompson, Susan E.; Barclay, Thomas; Howell, Steve B.; Still, Martin; Ibrahim, Khadeejah A. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Everett, Mark [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Mullally, Fergal; Rowe, Jason; Christiansen, Jessie L.; Twicken, Joseph D.; Clarke, Bruce D. [SETI Institute, 189 Bernardo Avenue, Suite 100, Mountain View, CA 94043 (United States); Kurtz, Donald W.; Hambleton, Kelly, E-mail: susan.e.thompson@nasa.gov [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom)

2012-07-01T23:59:59.000Z

55

Modeling Tidal Freshwater Marsh Sustainability in the Sacramento–San Joaquin Delta Under a Broad Suite of Potential Future Scenarios  

E-Print Network [OSTI]

in the face of sea-level rise: a hybrid modeling approachcoastal marshes to sea-level rise: Survival or submergence?distribution with sea-level rise: evaluating the role of

Swanson, Kathleen M.; Drexler, Judith Z.; Fuller, Christopher C.; Schoellhamer, David H.

2015-01-01T23:59:59.000Z

56

Climate Modeling using High-Performance Computing  

SciTech Connect (OSTI)

The Center for Applied Scientific Computing (CASC) and the LLNL Climate and Carbon Science Group of Energy and Environment (E and E) are working together to improve predictions of future climate by applying the best available computational methods and computer resources to this problem. Over the last decade, researchers at the Lawrence Livermore National Laboratory (LLNL) have developed a number of climate models that provide state-of-the-art simulations on a wide variety of massively parallel computers. We are now developing and applying a second generation of high-performance climate models. Through the addition of relevant physical processes, we are developing an earth systems modeling capability as well.

Mirin, A A

2007-02-05T23:59:59.000Z

57

Smart Grid Cybersecurity: Job Performance Model Report and Phase...  

Broader source: Energy.gov (indexed) [DOE]

Cybersecurity: Job Performance Model Report and Phase 1 Overview (August 2012) Smart Grid Cybersecurity: Job Performance Model Report and Phase 1 Overview (August 2012) In the...

58

System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report  

SciTech Connect (OSTI)

The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail.

Freeman, J.; Whitmore, J.; Kaffine, L.; Blair, N.; Dobos, A. P.

2013-12-01T23:59:59.000Z

59

Sandia National Laboratories: PV Performance Modeling Collaborative  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik Spoerke SSLSMolten-Salt StorageNoLongAnalysisPV Performance Modeling

60

Fitting orbits to tidal streams  

E-Print Network [OSTI]

Recent years have seen the discovery of many tidal streams through the Galaxy. Relatively straightforward observations of a stream allow one to deduce three phase-space coordinates of an orbit. An algorithm is presented that reconstructs the missing phase-space coordinates from these data. The reconstruction starts from assumed values of the Galactic potential and a distance to one point on the orbit, but with noise-free data the condition that energy be conserved on the orbit enables one to reject incorrect assumptions. The performance of the algorithm is investigated when errors are added to the input data that are comparable to those in published data for the streams of Pal 5. It is found that the algorithm returns distances and proper motions that are accurate to of order one percent, and enables one to reject quite reasonable but incorrect trial potentials. In practical applications it will be important to minimize errors in the input data, and there is considerable scope for doing this.

James Binney

2008-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

High performance computing and numerical modelling  

E-Print Network [OSTI]

Numerical methods play an ever more important role in astrophysics. This is especially true in theoretical works, but of course, even in purely observational projects, data analysis without massive use of computational methods has become unthinkable. The key utility of computer simulations comes from their ability to solve complex systems of equations that are either intractable with analytic techniques or only amenable to highly approximative treatments. Simulations are best viewed as a powerful complement to analytic reasoning, and as the method of choice to model systems that feature enormous physical complexity such as star formation in evolving galaxies, the topic of this 43rd Saas Fee Advanced Course. The organizers asked me to lecture about high performance computing and numerical modelling in this winter school, and to specifically cover the basics of numerically treating gravity and hydrodynamics in the context of galaxy evolution. This is still a vast field, and I necessarily had to select a subset ...

,

2014-01-01T23:59:59.000Z

62

Tidal Heating of Terrestrial Extra-Solar Planets and Implications for their Habitability  

E-Print Network [OSTI]

The tidal heating of hypothetical rocky (or terrestrial) extra-solar planets spans a wide range of values depending on stellar masses and initial orbits. Tidal heating may be sufficiently large (in many cases, in excess of radiogenic heating) and long-lived to drive plate tectonics, similar to the Earth's, which may enhance the planet's habitability. In other cases, excessive tidal heating may result in Io-like planets with violent volcanism, probably rendering them unsuitable for life. On water-rich planets, tidal heating may generate sub-surface oceans analogous to Europa's with similar prospects for habitability. Tidal heating may enhance the outgassing of volatiles, contributing to the formation and replenishment of a planet's atmosphere. To address these issues, we model the tidal heating and evolution of hypothetical extra-solar terrestrial planets. The results presented here constrain the orbital and physical properties required for planets to be habitable.

Brian Jackson; Rory Barnes; Richard Greenberg

2008-08-20T23:59:59.000Z

63

A Comparison of HCCI Engine Performance Data and Kinetic Modeling...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

of HCCI Engine Performance Data and Kinetic Modeling Results over a Wide Rangeof Gasoline Range Surrogate Fuel Blends A Comparison of HCCI Engine Performance Data and Kinetic...

64

Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade  

SciTech Connect (OSTI)

This paper describes the structural design of a tidal composite blade. The structural design is preceded by two steps: hydrodynamic design and determination of extreme loads. The hydrodynamic design provides the chord and twist distributions along the blade length that result in optimal performance of the tidal turbine over its lifetime. The extreme loads, i.e. the extreme flap and edgewise loads that the blade would likely encounter over its lifetime, are associated with extreme tidal flow conditions and are obtained using a computational fluid dynamics (CFD) software. Given the blade external shape and the extreme loads, we use a laminate-theory-based structural design to determine the optimal layout of composite laminas such that the ultimate-strength and buckling-resistance criteria are satisfied at all points in the blade. The structural design approach allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. In addition, certain fabrication criteria are imposed, for example, each composite laminate must be an integral multiple of its constituent ply thickness. In the present effort, the structural design uses only static extreme loads; dynamic-loads-based fatigue design will be addressed in the future. Following the blade design, we compute the distributed structural properties, i.e. flap stiffness, edgewise stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Such properties are required by hydro-elastic codes to model the tidal current turbine and to perform modal, stability, loads, and response analyses.

Bir, G. S.; Lawson, M. J.; Li, Y.

2011-10-01T23:59:59.000Z

65

Sandia National Laboratories: PV Reliability & Performance Model  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Generator Modeling Radar Friendly Blades Special Programs Techno-Economic Modeling, Analysis, and Support Analysis, Modeling, Cost of Energy, and Policy Impact: Wind Vision 2014...

66

Sandia National Laboratories: Performance Modeling Workshop Presentati...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Generator Modeling Radar Friendly Blades Special Programs Techno-Economic Modeling, Analysis, and Support Analysis, Modeling, Cost of Energy, and Policy Impact: Wind Vision 2014...

67

Low Temperature Performance: Performance Modeling | Department of Energy  

Energy Savers [EERE]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector General Office0-72.pdfGeorgeDoesn't Happen toLeveragingLindseyLong-TermLosofLow CostPerformance:

68

GLOBAL CHANGE AND TIDAL FRESHWATER WETLANDS  

E-Print Network [OSTI]

Chapter 23 GLOBAL CHANGE AND TIDAL FRESHWATER WETLANDS: SCENARIOS AND IMPACTS Scott C. Neubauer Tidal Freshwater Wetlands, edited by Aat Barendregt, Dennis Whigham & Andrew Baldwin 2009, viii + 320pp Publishers GmbH This chapter was originally published in the book ,,Tidal Freshwater Wetlands". The copy

Neubauer, Scott C.

69

Multiscale heterogeneity characterization of tidal channel, tidal delta and foreshore facies, Almond Formation outcrops, Rock Springs uplift, Wyoming  

SciTech Connect (OSTI)

In order to accurately predict fluid flow within a reservoir, variability in the rock properties at all scales relevant to the specific depositional environment needs to be taken into account. The present work describes rock variability at scales from hundreds of meters (facies level) to millimeters (laminae) based on outcrop studies of the Almond Formation. Tidal channel, tidal delta and foreshore facies were sampled on the eastern flank of the Rock Springs uplift, southeast of Rock Springs, Wyoming. The Almond Fm. was deposited as part of a mesotidal Upper Cretaceous transgressive systems tract within the greater Green River Basin. Bedding style, lithology, lateral extent of beds of bedsets, bed thickness, amount and distribution of depositional clay matrix, bioturbation and grain sorting provide controls on sandstone properties that may vary more than an order of magnitude within and between depositional facies in outcrops of the Almond Formation. These features can be mapped on the scale of an outcrop. The products of diagenesis such as the relative timing of carbonate cement, scale of cemented zones, continuity of cemented zones, selectively leached framework grains, lateral variability of compaction of sedimentary rock fragments, and the resultant pore structure play an equally important, although less predictable role in determining rock property heterogeneity. A knowledge of the spatial distribution of the products of diagenesis such as calcite cement or compaction is critical to modeling variation even within a single facies in the Almond Fin. because diagenesis can enhance or reduce primary (depositional) rock property heterogeneity. Application of outcrop heterogeneity models to the subsurface is greatly hindered by differences in diagenesis between the two settings. The measurements upon which this study is based were performed both on drilled outcrop plugs and on blocks.

Schatzinger, R.A.; Tomutsa, L. [BDM Petroleum Technologies, Bartlesville, OK (United States)

1997-08-01T23:59:59.000Z

70

Tidal Energy System for On-Shore Power Generation  

SciTech Connect (OSTI)

Addressing the urgent need to develop LCOE competitive renewable energy solutions for US energy security and to replace fossil-fuel generation with the associated benefits to environment impacts including a reduction in CO2 emissions, this Project focused on the advantages of using hydraulic energy transfer (HET) in large-scale Marine Hydrokinetic (MHK) systems for harvesting off-shore tidal energy in US waters. A recent DOE resource assessment, identifies water power resources have a potential to meet 15% of the US electric supply by 2030, with MHK technologies being a major component. The work covered a TRL-4 laboratory proof-in-concept demonstration plus modeling of a 15MW full scale system based on an approach patented by NASA-JPL, in which submerged high-ratio gearboxes and electrical generators in conventional MHK turbine systems are replaced by a submerged hydraulic radial pump coupled to on-shore hydraulic motors driving a generator. The advantages are; first, the mean-time-between-failure (MTBF), or maintenance, can be extended from approximately 1 to 5 years and second, the range of tidal flow speeds which can be efficiently harvested can be extended beyond that of a conventional submerged generator. The approach uses scalable, commercial-off-the-shelf (COTS) components, facilitating scale-up and commercialization. All the objectives of the Project have been successfully met (1) A TRL4 system was designed, constructed and tested. It simulates a tidal energy turbine, with a 2-m diameter blade in up to a 2.9 m/sec flow. The system consists of a drive motor assembly providing appropriate torque and RPM, attached to a radial piston pump. The pump circulates pressurized, environmentally-friendly, HEES hydraulic fluid in a closed loop to an axial piston motor which drives an electrical generator, with a resistive load. The performance of the components, subsystems and system were evaluated during simulated tidal cycles. The pump is contained in a tank for immersion testing. The COTS pump and motor were selected to scale to MW size and were oversized for the TRL-4 demonstration, operating at only 1-6% of rated values. Nevertheless, in for 2-18 kW drive power, in agreement with manufacturer performance data, we measured efficiencies of 85-90% and 75-80% for the pump and motor, respectively. These efficiencies being 95-96% at higher operating powers. (2) Two follow-on paths were identified. In both cases conventional turbine systems can be modified, replacing existing gear box and generator with a hydraulic pump and on-shore components. On a conventional path, a TRL5/6 15kW turbine system can be engineered and tested on a barge at an existing site in Maine. Alternatively, on an accelerated path, a TRL-8 100kW system can be engineered and tested by modifying a team member's existing MHK turbines, with barge and grid-connected test sites in-place. On both paths the work can be expedited and cost effective by reusing TRL-4 components, modifying existing turbines and using established test sites. (3) Sizing, performance modeling and costing of a scaled 15MW system, suitable for operation in Maine's Western Passage, was performed. COTS components are identified and the performance projections are favorable. The estimated LCOE is comparable to wind generation with peak production at high demand times. (4) We determined that a similar HET approach can be extended to on-shore and off-shore wind turbine systems. These are very large energy resources which can be addressed in parallel for even great National benefit. (5) Preliminary results on this project were presented at two International Conferences on renewable energy in 2012, providing a timely dissemination of information. We have thus demonstrated a proof-in-concept of a novel, tidal HET system that eliminates all submerged gears and electronics to improve reliability. Hydraulic pump efficiencies of 90% have been confirmed in simulated tidal flows between 1 and 3 m/s, and at only 1-6% of rated power. Total system efficiencies have also been modeled, up to MW-scale, for ti

Bruce, Allan J

2012-06-26T23:59:59.000Z

71

Using Tidal Tails to Probe Dark Matter Halos  

E-Print Network [OSTI]

We use simulations of merging galaxies to explore the sensitivity of the morphology of tidal tails to variations of the halo mass distributions in the parent galaxies. Our goal is to constrain the mass of dark halos in well-known merging pairs. We concentrate on prograde encounters between equal mass galaxies which represent the best cases for creating tidal tails, but also look at systems with different relative orientations, orbital energies and mass ratios. As the mass and extent of the dark halo increase in the model galaxies, the resulting tidal tails become shorter and less massive, even under the most favorable conditions for producing these features. Our simulations imply that the observed merging galaxies with long tidal tails ($\\sim 50-100$ kpc) such as NGC 4038/39 (the Antennae) and NGC 7252 probably have halo:disk+bulge mass ratios less than 10:1. These results conflict with the favored values of the dark halo mass of the Milky Way derived from satellite kinematics and the timing argument which give a halo:disk+bulge mass ratio of $\\sim 30:1$. However, the lower bound of the estimated dark halo mass in the Milky Way (mass ratio $\\sim 10:1$) is still consistent with the inferred tidal tail galaxy masses. Our results also conflict with the expectations of $\\Omega=1$ cosmologies such as CDM which predict much more massive and extended dark halos.

John Dubinski; J. Christopher Mihos; Lars Hernquist

1995-09-04T23:59:59.000Z

72

Tidal waves as yrast states in transitional nuclei  

E-Print Network [OSTI]

The yrast states of transitional nuclei are described as quadrupole waves running over the nuclear surface, which we call tidal waves. In contrast to a rotor, which generates angular momentum by increasing the angular velocity at approximately constant deformation, a tidal wave generates angular momentum by increasing the deformation at approximately constant angular velocity. The properties of the tidal waves are calculated by means of the cranking model in a microscopic way. The calculated energies and E2 transition probabilities of the yrast states in the transitional nuclides with $Z$= 44, 46, 48 and $N=56, 58, ..., 66$ reproduce the experiment in detail. The nonlinear response of the nucleonic orbitals results in a strong coupling between shape and single particle degrees of freedom.

S. Frauendorf; Y. Gu; J. Sun

2010-02-16T23:59:59.000Z

73

SPH simulations of tidally unstable accretion disks in cataclysmic variables  

E-Print Network [OSTI]

We numerically study the precessing disk model for superhump in the SU~UMa subclass of cataclysmic variables, using a two dimensional SPH code specifically designed for thin disk problems. Two disk simulations for a binary with mass ratio $q=\\frac{3}{17}$ (similar to OY~Car) are performed, in order to investigate the Lubow (1991 a,b) tidal resonance instability mechanism. In the first calculation, a disk evolves under steady mass transfer from $L_1$. In the second simulation, mass is added in Keplerian orbit to the inner disk. The two disks follow similar evolutionary paths. However the $L_1$ stream-disk interaction is found to slow the disk's radial expansion and to circularise gas orbits. The initial eccentricity growth in our simulations is exponential at a rate slightly less than predicted by Lubow (1991a). We do not observe a clearing of material from the resonance region via the disk's tidal response to the $m=2$ component of the binary potential as was described in Lubow (1992). Instead the $m=2$ response weakens as the disk eccentricty increases. Both disks reach an eccentric equilibrium state, in which they undergo prograde precession. The rate of viscous energy dissipation in the disks has a periodic excess with a period matching the disk's rotation. The source is identified as a large region in the outer disk, and the mechanism by which it is produced is identified. The time taken for the periodic excess to develop is consistent with the first appearance of superhumps in a superoutburst.

James R. Murray

1995-11-08T23:59:59.000Z

74

Tidal Residual Eddies and their Effect on Water Exchange in Puget Sound  

SciTech Connect (OSTI)

Tidal residual eddies are one of the important hydrodynamic features in tidally dominant estuaries and coastal bays, and they could have significant effects on water exchange in a tidal system. This paper presents a modeling study of tides and tidal residual eddies in Puget Sound, a tidally dominant fjord-like estuary in the Pacific Northwest coast, using a three-dimensional finite-volume coastal ocean model. Mechanisms of vorticity generation and asymmetric distribution patterns around an island/headland were analyzed using the dynamic vorticity transfer approach and numerical experiments. Model results of Puget Sound show that a number of large twin tidal residual eddies exist in the Admiralty Inlet because of the presence of major headlands in the inlet. Simulated residual vorticities near the major headlands indicate that the clockwise tidal residual eddy (negative vorticity) is generally stronger than the anticlockwise eddy (positive vorticity) because of the effect of Coriolis force. The effect of tidal residual eddies on water exchange in Puget Sound and its sub-basins were evaluated by simulations of dye transport. It was found that the strong transverse variability of residual currents in the Admiralty Inlet results in a dominant seaward transport along the eastern shore and a dominant landward transport along the western shore of the Inlet. A similar transport pattern in Hood Canal is caused by the presence of tidal residual eddies near the entrance of the canal. Model results show that tidal residual currents in Whidbey Basin are small in comparison to other sub-basins. A large clockwise residual circulation is formed around Vashon Island near entrance of South Sound, which can potentially constrain the water exchange between the Central Basin and South Sound.

Yang, Zhaoqing; Wang, Taiping

2013-08-30T23:59:59.000Z

75

System Identification and Modelling of a High Performance Hydraulic Actuator  

E-Print Network [OSTI]

System Identification and Modelling of a High Performance Hydraulic Actuator Benoit Boulet, Laeeque with the experimental identification and modelling of the nonlinear dynamics ofa high performance hydraulic actuator. The actuator properties and performance are also discussed. 1 Introduction Hydraulic actuation used to be

Hayward, Vincent

76

Applying High Performance Computing to Analyzing by Probabilistic Model Checking  

E-Print Network [OSTI]

Applying High Performance Computing to Analyzing by Probabilistic Model Checking Mobile Cellular on the use of high performance computing in order to analyze with the proba- bilistic model checker PRISM. The Figure Generation Script 22 2 #12;1. Introduction We report in this paper on the use of high performance

Schneider, Carsten

77

A Variable Cell Model for Simulating Gas Condensate Reservoir Performance  

E-Print Network [OSTI]

, SPE-~~~ SPE 21428 A Variable Cell Model for Simulating Gas Condensate Reservoir Performance A of depletion performance of gas condensate reservoirs report the existence of a A variable cell model for simulating gas relatively high, near-constant, oil saturation in condensate reeervoir performance has been

Al-Majed, Abdulaziz Abdullah

78

A Knowledge Management Platform for Infrastructure Performance Modeling  

E-Print Network [OSTI]

Transportation Centers Program, in the interest of information exchange. The U.S. Government assumes no liability, utilization, evaluation and selection of performance models. Thus, the objective of the study is to build the capabilities of their own models. The platform advances infrastructure performance modeling because analysts

79

Electrical, Frequency and Thermal Measurement and Modelling of Supercapacitor Performance  

E-Print Network [OSTI]

Electrical, Frequency and Thermal Measurement and Modelling of Supercapacitor Performance Yasser--This paper presents an evaluation of commercial supercapacitors performance (ESR, C, self-discharge, Pmax, Emax, coulumbic efficiency, etc), under different conditions. Characterization of supercapacitor

Paris-Sud XI, Université de

80

Hybrid Model of Existing Buildings for Transient Thermal Performance Estimation  

E-Print Network [OSTI]

Building level energy models are important to provide accurate prediction of energy consumption for building performance diagnosis and energy efficiency assessment of retrofitting alternatives for building performance upgrading. Simplified...

Xu, X.; Wang, S.

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Degradation Pathway Models for Photovoltaics Module Lifetime Performance  

E-Print Network [OSTI]

Degradation Pathway Models for Photovoltaics Module Lifetime Performance Nicholas R. Wheeler, Laura data from Underwriter Labs, featuring measurements taken on 18 identical photovoltaic (PV) modules in modules and their effects on module performance over lifetime. Index Terms--photovoltaics, statistical

Rollins, Andrew M.

82

Detailed Performance Model for Photovoltaic Systems: Preprint  

SciTech Connect (OSTI)

This paper presents a modified current-voltage relationship for the single diode model. The single-diode model has been derived from the well-known equivalent circuit for a single photovoltaic cell. The modification presented in this paper accounts for both parallel and series connections in an array.

Tian, H.; Mancilla-David, F.; Ellis, K.; Muljadi, E.; Jenkins, P.

2012-07-01T23:59:59.000Z

83

An Investigation into Satellite Drag Modeling Performance  

E-Print Network [OSTI]

parameters, but with so much variability, capturing the small scale changes the atmosphere undergoes is difficult. Many techniques have been developed to fine tune atmospheric models to include these variations. One such technique is dynamic calibration... ............................................................................. 49 2.3.1 Atmospheric Modeling Upgrade ..................................................... 50 2.3.1.1 NRLMSISE-2000 Modification ...................................................... 50 2.3.1.2 DCA Corrections Modification...

Mance, Stephen

2010-03-23T23:59:59.000Z

84

Tidally-induced thermonuclear Supernovae  

E-Print Network [OSTI]

We discuss the results of 3D simulations of tidal disruptions of white dwarfs by moderate-mass black holes as they may exist in the cores of globular clusters or dwarf galaxies. Our simulations follow self-consistently the hydrodynamic and nuclear evolution from the initial parabolic orbit over the disruption to the build-up of an accretion disk around the black hole. For strong enough encounters (pericentre distances smaller than about 1/3 of the tidal radius) the tidal compression is reversed by a shock and finally results in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar limit, we find exploding examples throughout the whole white dwarf mass range. There is, however, a restriction on the masses of the involved black holes: black holes more massive than 2 × 10 5 M? swallow a typical 0.6 M ? white dwarf before their tidal forces can overwhelm the star’s selfgravity. Therefore, this mechanism is characteristic for black holes of moderate masses. The material that remains bound to the black hole settles into an accretion disk and produces an X-ray flare close to the Eddington limit of LEdd ? 10 41 erg/s (Mbh/1000M?), typically lasting for a few months. The combination of a peculiar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate-mass black holes. The next generation of wide field space-based instruments should be able to detect such events. 1.

Stephan Rosswog; Enrico Ramirez-ruiz; W. Raphael Hix

85

Tidally-induced thermonuclear Supernovae  

E-Print Network [OSTI]

We discuss the results of 3D simulations of tidal disruptions of white dwarfs by moderate-mass black holes as they may exist in the cores of globular clusters or dwarf galaxies. Our simulations follow self-consistently the hydrodynamic and nuclear evolution from the initial parabolic orbit over the disruption to the build-up of an accretion disk around the black hole. For strong enough encounters (pericentre distances smaller than about 1/3 of the tidal radius) the tidal compression is reversed by a shock and finally results in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar limit, we find exploding examples throughout the whole white dwarf mass range. There is, however, a restriction on the masses of the involved black holes: black holes more massive than $2\\times 10^5$ M$_\\odot$ swallow a typical 0.6 M$_\\odot$ dwarf before their tidal forces can overwhelm the star's self-gravity. Therefore, this mechanism is characteristic for black holes of moderate masses. The material that remains bound to the black hole settles into an accretion disk and produces an X-ray flare close to the Eddington limit of $L_{\\rm Edd} \\simeq 10^{41} {\\rm erg/s} M_{\\rm bh}/1000 M$_\\odot$), typically lasting for a few months. The combination of a peculiar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate-mass black holes. The next generation of wide field space-based instruments should be able to detect such events.

S. Rosswog; E. Ramirez-Ruiz; W. R. Hix

2008-11-13T23:59:59.000Z

86

A Comparison of HCCI Engine Performance Data and Kinetic Modeling...  

Broader source: Energy.gov (indexed) [DOE]

of HCCI Engine Performance Data and Kinetic Modeling Results over a Wide Range of Gasoline Range Surrogate Fuel Blends Bruce G. Bunting and Scott Eaton, Oak Ridge National...

87

Application Insight Through Performance Modeling Gabriel Marin  

E-Print Network [OSTI]

that estimate the maximum gain expected from tuning different parts of an application, or from increasing the number of machine resources. We show how this metric helped iden- tify a bottleneck in the ASCI Sweep3D benchmark where the lack of instruction-level parallelism limited performance. Transforming one frequently

Marin, Gabriel

88

TIDAL DISSIPATION COMPARED TO SEISMIC DISSIPATION: IN SMALL BODIES, EARTHS, AND SUPER-EARTHS  

SciTech Connect (OSTI)

While the seismic quality factor and phase lag are defined solely by the bulk properties of the mantle, their tidal counterparts are determined by both the bulk properties and the size effect (self-gravitation of a body as a whole). For a qualitative estimate, we model the body with a homogeneous sphere, and express the tidal phase lag through the lag in a sample of material. Although simplistic, our model is sufficient to understand that the lags are not identical. The difference emerges because self-gravitation pulls the tidal bulge down. At low frequencies, this reduces strain and the damping rate, making tidal damping less efficient in larger objects. At higher frequencies, competition between self-gravitation and rheology becomes more complex, though for sufficiently large super-Earths the same rule applies: the larger the planet, the weaker the tidal dissipation in it. Being negligible for small terrestrial planets and moons, the difference between the seismic and tidal lagging (and likewise between the seismic and tidal damping) becomes very considerable for large exoplanets (super-Earths). In those, it is much lower than what one might expect from using a seismic quality factor. The tidal damping rate deviates from the seismic damping rate, especially in the zero-frequency limit, and this difference takes place for bodies of any size. So the equal in magnitude but opposite in sign tidal torques, exerted on one another by the primary and the secondary, have their orbital averages going smoothly through zero as the secondary crosses the synchronous orbit. We describe the mantle rheology with the Andrade model, allowing it to lean toward the Maxwell model at the lowest frequencies. To implement this additional flexibility, we reformulate the Andrade model by endowing it with a free parameter {zeta} which is the ratio of the anelastic timescale to the viscoelastic Maxwell time of the mantle. Some uncertainty in this parameter's frequency dependence does not influence our principal conclusions.

Efroimsky, Michael, E-mail: michael.efroimsky@usno.navy.mil [U.S. Naval Observatory, Washington, DC 20392 (United States)

2012-02-20T23:59:59.000Z

89

TIDAL FRICTION AND TIDAL LAGGING. APPLICABILITY LIMITATIONS OF A POPULAR FORMULA FOR THE TIDAL TORQUE  

SciTech Connect (OSTI)

Tidal torques play a key role in rotational dynamics of celestial bodies. They govern these bodies' tidal despinning and also participate in the subtle process of entrapment of these bodies into spin-orbit resonances. This makes tidal torques directly relevant to the studies of habitability of planets and their moons. Our work begins with an explanation of how friction and lagging should be built into the theory of bodily tides. Although much of this material can be found in various publications, a short but self-consistent summary on the topic has been lacking in the hitherto literature, and we are filling the gap. After these preparations, we address a popular concise formula for the tidal torque, which is often used in the literature, for planets or stars. We explain why the derivation of this expression, offered in the paper by Goldreich and in the books by Kaula (Equation (4.5.29)) and Murray and Dermott (Equation (4.159)), implicitly sets the time lag to be frequency independent. Accordingly, the ensuing expression for the torque can be applied only to bodies having a very special (and very hypothetical) rheology which makes the time lag frequency independent, i.e., the same for all Fourier modes in the spectrum of tide. This expression for the torque should not be used for bodies of other rheologies. Specifically, the expression cannot be combined with an extra assertion of the geometric lag being constant, because at finite eccentricities the said assumption is incompatible with the constant-time-lag condition.

Efroimsky, Michael; Makarov, Valeri V., E-mail: michael.efroimsky@usno.navy.mil, E-mail: vvm@usno.navy.mil [US Naval Observatory, Washington, DC 20392 (United States)

2013-02-10T23:59:59.000Z

90

Effects of Tidal Turbine Noise on Fish Hearing and Tissues - Draft Final Report - Environmental Effects of Marine and Hydrokinetic Energy  

SciTech Connect (OSTI)

Snohomish Public Utility District No.1 plans to deploy two 6 meter OpenHydro tidal turbines in Admiralty Inlet in Puget Sound, under a FERC pilot permitting process. Regulators and stakeholders have raised questions about the potential effect of noise from the turbines on marine life. Noise in the aquatic environment is known to be a stressor to many types of aquatic life, including marine mammals, fish and birds. Marine mammals and birds are exceptionally difficult to work with for technical and regulatory reasons. Fish have been used as surrogates for other aquatic organisms as they have similar auditory structures. This project was funded under the FY09 Funding Opportunity Announcement (FOA) to Snohomish PUD, in partnership with the University of Washington - Northwest National Marine Renewable Energy Center, the Sea Mammal Research Unit, and Pacific Northwest National Laboratory. The results of this study will inform the larger research project outcomes. Proposed tidal turbine deployments in coastal waters are likely to propagate noise into nearby waters, potentially causing stress to native organisms. For this set of experiments, juvenile Chinook salmon (Oncorhynchus tshawytscha) were used as the experimental model. Plans exist for prototype tidal turbines to be deployed into their habitat. Noise is known to affect fish in many ways, such as causing a threshold shift in auditory sensitivity or tissue damage. The characteristics of noise, its spectra and level, are important factors that influence the potential for the noise to injure fish. For example, the frequency range of the tidal turbine noise includes the audiogram (frequency range of hearing) of most fish. This study was performed during FY 2011 to determine if noise generated by a 6-m diameter OpenHydro turbine might affect juvenile Chinook salmon hearing or cause barotrauma. Naturally spawning stocks of Chinook salmon that utilize Puget Sound are listed as threatened (http://www.nwr.noaa.gov/ESA-Salmon-Listings/Salmon-Populations/Chinook/CKPUG.cfm); the fish used in this experiment were hatchery raised and their populations are not in danger of depletion. After they were exposed to simulated tidal turbine noise, the hearing of juvenile Chinook salmon was measured and necropsies performed to check for tissue damage. Experimental groups were (1) noise exposed, (2) control (the same handling as treatment fish but without exposure to tidal turbine noise), and (3) baseline (never handled). Experimental results indicate that non-lethal, low levels of tissue damage may have occurred but that there were no effects of noise exposure on the auditory systems of the test fish.

Halvorsen, Michele B.; Carlson, Thomas J.; Copping, Andrea E.

2011-09-30T23:59:59.000Z

91

Disc formation from stellar tidal disruptions  

E-Print Network [OSTI]

The potential of tidal disruption of stars to probe otherwise quiescent supermassive black holes cannot be exploited, if their dynamics is not fully understood. So far, the observational appearance of these events has been commonly derived from analytical extrapolations of the debris dynamical properties just after the stellar disruption. In this paper, we perform hydrodynamical simulations of stars in highly eccentric orbits, that follow the stellar debris after disruption and investigate their ultimate fate. We demonstrate that gas debris circularize on an orbital timescale because relativistic apsidal precession causes the stream to self-cross. The higher the eccentricity and/or the deeper the encounter, the faster is the circularization. If the internal energy deposited by shocks during stream self-interaction is readily radiated, the gas forms a narrow ring at the circularization radius. It will then proceed to accrete viscously at a super-Eddington rate, puffing up under radiation pressure. If instead c...

Bonnerot, Clément; Lodato, Giuseppe; Price, Daniel J

2015-01-01T23:59:59.000Z

92

Performance Modeling and Access Methods for Temporal Database Management Systems  

E-Print Network [OSTI]

implementation issues. Database systems with temporal support maintain history data on line together with current. Performance Modeling and Access Methods for Temporal Database Management Systems TR86-018 August. #12;Performance Modeling and Access Methods for Temporal Database Management Systems by Ilsoo Ahn

North Carolina at Chapel Hill, University of

93

Performance Modeling of Shared Memory Programsof SharedMemory Programs  

E-Print Network [OSTI]

nus edu sg/~teoymURL: www.comp.nus.edu.sg/ teoym 7th Workshop on High Performance Computing UPM Analysis l i l d l­ Analytical Model · Summary 1 November 2011 47th Workshop on High Performance Computing November 2011 57th Workshop on High Performance Computing (invited talk) #12;R l t d W kRelated Work

Teo, Yong-Meng

94

Sandia National Laboratories: PV Performance Modeling Collaborative  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik Spoerke SSLSMolten-Salt StorageNoLongAnalysisPV Performance

95

European Wave and Tidal Energy Conference  

Broader source: Energy.gov [DOE]

The European Wave and Tidal Energy Conference (EWTEC) series are international, technical and scientific conferences, focussed on ocean renewable energy and widely respected for their commitment to...

96

Developing an Energy Performance Modeling Startup Kit  

SciTech Connect (OSTI)

In 2011, the NAHB Research Center began the first part of the multi-year effort by assessing the needs and motivations of residential remodelers regarding energy performance remodeling. The scope is multifaceted - all perspectives will be sought related to remodeling firms ranging in size from small-scale, sole proprietor to national. This will allow the Research Center to gain a deeper understanding of the remodeling and energy retrofit business and the needs of contractors when offering energy upgrade services. To determine the gaps and the motivation for energy performance remodeling, the NAHB Research Center conducted (1) an initial series of focus groups with remodelers at the 2011 International Builders' Show, (2) a second series of focus groups with remodelers at the NAHB Research Center in conjunction with the NAHB Spring Board meeting in DC, and (3) quantitative market research with remodelers based on the findings from the focus groups. The goal was threefold, to: Understand the current remodeling industry and the role of energy efficiency; Identify the gaps and barriers to adding energy efficiency into remodeling; and Quantify and prioritize the support needs of professional remodelers to increase sales and projects involving improving home energy efficiency. This report outlines all three of these tasks with remodelers.

Wood, A.

2012-10-01T23:59:59.000Z

97

Cost and Performance Assumptions for Modeling Electricity Generation Technologies  

SciTech Connect (OSTI)

The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

Tidball, R.; Bluestein, J.; Rodriguez, N.; Knoke, S.

2010-11-01T23:59:59.000Z

98

Tidal Electric | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:Seadov Pty LtdSteen,Ltd Jump JumpAl., 1978) |Thrall,Tibagi Energetica Jump to:Tidal

99

A Linear Parabolic Trough Solar Collector Performance Model  

E-Print Network [OSTI]

A performance model has been programmed for solar thermal collector based on a linear, tracking parabolic trough reflector focused on a surface-treated metallic pipe receiver enclosed in an evacuated transparent tube: a Parabolic Trough Solar...

Qu, M.; Archer, D.; Masson, S.

2006-01-01T23:59:59.000Z

100

Models used to assess the performance of photovoltaic systems.  

SciTech Connect (OSTI)

This report documents the various photovoltaic (PV) performance models and software developed and utilized by researchers at Sandia National Laboratories (SNL) in support of the Photovoltaics and Grid Integration Department. In addition to PV performance models, hybrid system and battery storage models are discussed. A hybrid system using other distributed sources and energy storage can help reduce the variability inherent in PV generation, and due to the complexity of combining multiple generation sources and system loads, these models are invaluable for system design and optimization. Energy storage plays an important role in reducing PV intermittency and battery storage models are used to understand the best configurations and technologies to store PV generated electricity. Other researcher's models used by SNL are discussed including some widely known models that incorporate algorithms developed at SNL. There are other models included in the discussion that are not used by or were not adopted from SNL research but may provide some benefit to researchers working on PV array performance, hybrid system models and energy storage. The paper is organized into three sections to describe the different software models as applied to photovoltaic performance, hybrid systems, and battery storage. For each model, there is a description which includes where to find the model, whether it is currently maintained and any references that may be available. Modeling improvements underway at SNL include quantifying the uncertainty of individual system components, the overall uncertainty in modeled vs. measured results and modeling large PV systems. SNL is also conducting research into the overall reliability of PV systems.

Stein, Joshua S.; Klise, Geoffrey T.

2009-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Modeling the Performance and Energy of Storage Arrays  

E-Print Network [OSTI]

, it is desirable that techniques provide their energy savings while minimizing their impact on performance. DespiteModeling the Performance and Energy of Storage Arrays Sankaran Sivathanu Georgia Institute techniques for power optimization in storage. Given an ar- bitrary trace of disk requests, we split

Liu, Ling

102

Execution-Less Performance Modeling Roman Iakymchuk and Paolo Bientinesi  

E-Print Network [OSTI]

Execution-Less Performance Modeling Roman Iakymchuk and Paolo Bientinesi AICES, RWTH Aachen occurring in higher- level algorithms--like a matrix factorization--is then pre- dicted by combining a priori; the prediction of performance therefore reduces to the pre- diction of Execution time. Our

103

Atmospheric heat redistribution and collapse on tidally locked rocky planets  

E-Print Network [OSTI]

Atmospheric collapse is likely to be of fundamental importance to tidally locked rocky exoplanets but remains understudied. Here, general results on the heat transport and stability of tidally locked terrestrial-type atmospheres are reported. First, the problem is modeled with an idealized 3D general circulation model (GCM) with gray gas radiative transfer. It is shown that over a wide range of parameters the atmospheric boundary layer, rather than the large-scale circulation, is the key to understanding the planetary energy balance. Through a scaling analysis of the interhemispheric energy transfer, theoretical expressions for the day-night temperature difference and surface wind speed are created that reproduce the GCM results without tuning. Next, the GCM is used with correlated-k radiative transfer to study heat transport for two real gases (CO2 and CO). For CO2, empirical formulae for the collapse pressure as a function of planetary mass and stellar flux are produced, and critical pressures for atmospher...

Wordsworth, Robin

2014-01-01T23:59:59.000Z

104

Human performance modeling for system of systems analytics: combat performance-shaping factors.  

SciTech Connect (OSTI)

The US military has identified Human Performance Modeling (HPM) as a significant requirement and challenge of future systems modeling and analysis initiatives. To support this goal, Sandia National Laboratories (SNL) has undertaken a program of HPM as an integral augmentation to its system-of-system (SoS) analytics capabilities. The previous effort, reported in SAND2005-6569, evaluated the effects of soldier cognitive fatigue on SoS performance. The current effort began with a very broad survey of any performance-shaping factors (PSFs) that also might affect soldiers performance in combat situations. The work included consideration of three different approaches to cognition modeling and how appropriate they would be for application to SoS analytics. This bulk of this report categorizes 47 PSFs into three groups (internal, external, and task-related) and provides brief descriptions of how each affects combat performance, according to the literature. The PSFs were then assembled into a matrix with 22 representative military tasks and assigned one of four levels of estimated negative impact on task performance, based on the literature. Blank versions of the matrix were then sent to two ex-military subject-matter experts to be filled out based on their personal experiences. Data analysis was performed to identify the consensus most influential PSFs. Results indicate that combat-related injury, cognitive fatigue, inadequate training, physical fatigue, thirst, stress, poor perceptual processing, and presence of chemical agents are among the PSFs with the most negative impact on combat performance.

Lawton, Craig R.; Miller, Dwight Peter

2006-01-01T23:59:59.000Z

105

Human performance modeling for system of systems analytics :soldier fatigue.  

SciTech Connect (OSTI)

The military has identified Human Performance Modeling (HPM) as a significant requirement and challenge of future systems modeling and analysis initiatives as can be seen in the Department of Defense's (DoD) Defense Modeling and Simulation Office's (DMSO) Master Plan (DoD 5000.59-P 1995). To this goal, the military is currently spending millions of dollars on programs devoted to HPM in various military contexts. Examples include the Human Performance Modeling Integration (HPMI) program within the Air Force Research Laboratory, which focuses on integrating HPMs with constructive models of systems (e.g. cockpit simulations) and the Navy's Human Performance Center (HPC) established in September 2003. Nearly all of these initiatives focus on the interface between humans and a single system. This is insufficient in the era of highly complex network centric SoS. This report presents research and development in the area of HPM in a system-of-systems (SoS). Specifically, this report addresses modeling soldier fatigue and the potential impacts soldier fatigue can have on SoS performance.

Lawton, Craig R.; Campbell, James E.; Miller, Dwight Peter

2005-10-01T23:59:59.000Z

106

Cost and Performance Model for Redox Flow Batteries  

SciTech Connect (OSTI)

A cost model was developed for all vanadium and iron-vanadium redox flow batteries. Electrochemical performance modeling was done to estimate stack performance at various power densities as a function of state of charge. This was supplemented with a shunt current model and a pumping loss model to estimate actual system efficiency. The operating parameters such as power density, flow rates and design parameters such as electrode aspect ratio, electrolyte flow channel dimensions were adjusted to maximize efficiency and minimize capital costs. Detailed cost estimates were obtained from various vendors to calculate cost estimates for present, realistic and optimistic scenarios. The main drivers for cost reduction for various chemistries were identified as a function of the energy to power ratio of the storage system. Levelized cost analysis further guided suitability of various chemistries for different applications.

Viswanathan, Vilayanur V.; Crawford, Aladsair J.; Stephenson, David E.; Kim, Soowhan; Wang, Wei; Li, Bin; Coffey, Greg W.; Thomsen, Edwin C.; Graff, Gordon L.; Balducci, Patrick J.; Kintner-Meyer, Michael CW; Sprenkle, Vincent L.

2014-02-01T23:59:59.000Z

107

Half Moon Cove Tidal Project. Feasibility report  

SciTech Connect (OSTI)

The proposed Half Moon Cove Tidal Power Project would be located in a small cove in the northern part of Cobscook Bay in the vicinity of Eastport, Maine. The project would be the first tidal electric power generating plant in the United States of America. The basin impounded by the barrier when full will approximate 1.2 square miles. The average tidal range at Eastport is 18.2 feet. The maximum spring tidal range will be 26.2 feet and the neap tidal range 12.8 feet. The project will be of the single pool-type single effect in which generation takes place on the ebb tide only. Utilizing an average mean tidal range of 18.2 feet the mode of operation enables generation for approximately ten and one-half (10-1/2) hours per day or slightly in excess of five (5) hours per tide. The installed capacity will be 12 MW utilizing 2 to 6 MW units. An axial flow, or Bulb type of turbine was selected for this study.

Not Available

1980-11-01T23:59:59.000Z

108

Personal Computer-Based Model for Cool Storage Performance Simulation  

E-Print Network [OSTI]

PERSONAL COMPUTER-BASED MODEL FOR COOL STORAGE PERFORMANCE SIMULATION Leszek M. Kasprowicz, Jerold W. Jones, and James Hitzfelder The University of Texas at Austin ust tin, ABSTRACT A personal computer based hourly simulation model... can be achieved by applying cool storage systems which use stored energy for air-conditioning purposes during peak periods. Customers benefit from cool storage in two ways. First, demand charges are reduced since customers with sufficient thermal...

Kasprowicz, L. M.; Jones, J. W.; Hitzfelder, J.

1990-01-01T23:59:59.000Z

109

Performance and Energy Modeling for Live Migration of Virtual Machines  

E-Print Network [OSTI]

Performance and Energy Modeling for Live Migration of Virtual Machines Haikun Liu , Cheng-Zhong Xu , Hai Jin , Jiayu Gong , Xiaofei Liao School of Computer Science and Technology Huazhong University of Science and Technology Wuhan, 430074, China {hjin, xfliao}@hust.edu.cn Department of Electrical

Xu, Cheng-Zhong

110

A Model of Extranet Implementation Success Effects on Business Performance  

E-Print Network [OSTI]

A Model of Extranet Implementation Success Effects on Business Performance Sanna M. Kallioranta Ph and Justification The eBusiness revolution is impossible to ignore. It has transformed businesses in virtually every and services, and eBusiness has transformed the way companies interact with customers, partners and employees

111

24 More Years of Numerical Weather Prediction: A Model Performance Model  

E-Print Network [OSTI]

24 More Years of Numerical Weather Prediction: A Model Performance Model Gerard Cats May 26, 2008 Abstract For two formulations of currently usual numerical weather prediction models the evolution in such a model is much 1 #12;24 More Years of Numerical Weather Prediction Gerard Cats higher than in a sis

Stoffelen, Ad

112

Reference Manual for the System Advisor Model's Wind Power Performance Model  

SciTech Connect (OSTI)

This manual describes the National Renewable Energy Laboratory's System Advisor Model (SAM) wind power performance model. The model calculates the hourly electrical output of a single wind turbine or of a wind farm. The wind power performance model requires information about the wind resource, wind turbine specifications, wind farm layout (if applicable), and costs. In SAM, the performance model can be coupled to one of the financial models to calculate economic metrics for residential, commercial, or utility-scale wind projects. This manual describes the algorithms used by the wind power performance model, which is available in the SAM user interface and as part of the SAM Simulation Core (SSC) library, and is intended to supplement the user documentation that comes with the software.

Freeman, J.; Jorgenson, J.; Gilman, P.; Ferguson, T.

2014-08-01T23:59:59.000Z

113

PHARAO Laser Source Flight Model: Design and Performances  

E-Print Network [OSTI]

In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.

Lévèque, Thomas; Esnault, François-Xavier; Delaroche, Christophe; Massonnet, Didier; Grosjean, Olivier; Buffe, Fabrice; Torresi, Patrizia; Bomer, Thierry; Pichon, Alexandre; Béraud, Pascal; Lelay, Jean-Pierre; Thomin, Stéphane; Laurent, Philippe

2015-01-01T23:59:59.000Z

114

A New Model to Simulate Energy Performance of VRF Systems  

SciTech Connect (OSTI)

This paper presents a new model to simulate energy performance of variable refrigerant flow (VRF) systems in heat pump operation mode (either cooling or heating is provided but not simultaneously). The main improvement of the new model is the introduction of the evaporating and condensing temperature in the indoor and outdoor unit capacity modifier functions. The independent variables in the capacity modifier functions of the existing VRF model in EnergyPlus are mainly room wet-bulb temperature and outdoor dry-bulb temperature in cooling mode and room dry-bulb temperature and outdoor wet-bulb temperature in heating mode. The new approach allows compliance with different specifications of each indoor unit so that the modeling accuracy is improved. The new VRF model was implemented in a custom version of EnergyPlus 7.2. This paper first describes the algorithm for the new VRF model, which is then used to simulate the energy performance of a VRF system in a Prototype House in California that complies with the requirements of Title 24 ? the California Building Energy Efficiency Standards. The VRF system performance is then compared with three other types of HVAC systems: the Title 24-2005 Baseline system, the traditional High Efficiency system, and the EnergyStar Heat Pump system in three typical California climates: Sunnyvale, Pasadena and Fresno. Calculated energy savings from the VRF systems are significant. The HVAC site energy savings range from 51 to 85percent, while the TDV (Time Dependent Valuation) energy savings range from 31 to 66percent compared to the Title 24 Baseline Systems across the three climates. The largest energy savings are in Fresno climate followed by Sunnyvale and Pasadena. The paper discusses various characteristics of the VRF systems contributing to the energy savings. It should be noted that these savings are calculated using the Title 24 prototype House D under standard operating conditions. Actual performance of the VRF systems for real houses under real operating conditions will vary.

Hong, Tianzhen; Pang, Xiufeng; Schetrit, Oren; Wang, Liping; Kasahara, Shinichi; Yura, Yoshinori; Hinokuma, Ryohei

2014-03-30T23:59:59.000Z

115

MODELING THE PERFORMANCE OF HIGH BURNUP THORIA AND URANIA PWR FUEL  

E-Print Network [OSTI]

Fuel performance models have been developed to assess the performance of ThO[subscript 2]-UO[subscript 2]

Long, Y.

116

Radionuclide release rates from spent fuel for performance assessment modeling  

SciTech Connect (OSTI)

In a scenario of aqueous transport from a high-level radioactive waste repository, the concentration of radionuclides in water in contact with the waste constitutes the source term for transport models, and as such represents a fundamental component of all performance assessment models. Many laboratory experiments have been done to characterize release rates and understand processes influencing radionuclide release rates from irradiated nuclear fuel. Natural analogues of these waste forms have been studied to obtain information regarding the long-term stability of potential waste forms in complex natural systems. This information from diverse sources must be brought together to develop and defend methods used to define source terms for performance assessment models. In this manuscript examples of measures of radionuclide release rates from spent nuclear fuel or analogues of nuclear fuel are presented. Each example represents a very different approach to obtaining a numerical measure and each has its limitations. There is no way to obtain an unambiguous measure of this or any parameter used in performance assessment codes for evaluating the effects of processes operative over many millennia. The examples are intended to suggest by example that in the absence of the ability to evaluate accuracy and precision, consistency of a broadly based set of data can be used as circumstantial evidence to defend the choice of parameters used in performance assessments.

Curtis, D.B.

1994-11-01T23:59:59.000Z

117

Instruction-level performance modeling and characterization of multimedia applications  

SciTech Connect (OSTI)

One of the challenges for characterizing and modeling realistic multimedia applications is the lack of access to source codes. On-chip performance counters effectively resolve this problem by monitoring run-time behaviors at the instruction-level. This paper presents a novel technique of characterizing and modeling workloads at the instruction level for realistic multimedia applications using hardware performance counters. A variety of instruction counts are collected from some multimedia applications, such as RealPlayer, GSM Vocoder, MPEG encoder/decoder, and speech synthesizer. These instruction counts can be used to form a set of abstract characteristic parameters directly related to a processor`s architectural features. Based on microprocessor architectural constraints and these calculated abstract parameters, the architectural performance bottleneck for a specific application can be estimated. Meanwhile, the bottleneck estimation can provide suggestions about viable architectural/functional improvement for certain workloads. The biggest advantage of this new characterization technique is a better understanding of processor utilization efficiency and architectural bottleneck for each application. This technique also provides predictive insight of future architectural enhancements and their affect on current codes. In this paper the authors also attempt to model architectural effect on processor utilization without memory influence. They derive formulas for calculating CPI{sub 0}, CPI without memory effect, and they quantify utilization of architectural parameters. These equations are architecturally diagnostic and predictive in nature. Results provide promise in code characterization, and empirical/analytical modeling.

Luo, Y. [Los Alamos National Lab., NM (United States). Scientific Computing Group; Cameron, K.W. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Computer Science

1999-06-01T23:59:59.000Z

118

Duct thermal performance models for large commercial buildings  

SciTech Connect (OSTI)

Despite the potential for significant energy savings by reducing duct leakage or other thermal losses from duct systems in large commercial buildings, California Title 24 has no provisions to credit energy-efficient duct systems in these buildings. A substantial reason is the lack of readily available simulation tools to demonstrate the energy-saving benefits associated with efficient duct systems in large commercial buildings. The overall goal of the Efficient Distribution Systems (EDS) project within the PIER High Performance Commercial Building Systems Program is to bridge the gaps in current duct thermal performance modeling capabilities, and to expand our understanding of duct thermal performance in California large commercial buildings. As steps toward this goal, our strategy in the EDS project involves two parts: (1) developing a whole-building energy simulation approach for analyzing duct thermal performance in large commercial buildings, and (2) using the tool to identify the energy impacts of duct leakage in California large commercial buildings, in support of future recommendations to address duct performance in the Title 24 Energy Efficiency Standards for Nonresidential Buildings. The specific technical objectives for the EDS project were to: (1) Identify a near-term whole-building energy simulation approach that can be used in the impacts analysis task of this project (see Objective 3), with little or no modification. A secondary objective is to recommend how to proceed with long-term development of an improved compliance tool for Title 24 that addresses duct thermal performance. (2) Develop an Alternative Calculation Method (ACM) change proposal to include a new metric for thermal distribution system efficiency in the reporting requirements for the 2005 Title 24 Standards. The metric will facilitate future comparisons of different system types using a common ''yardstick''. (3) Using the selected near-term simulation approach, assess the impacts of duct system improvements in California large commercial buildings, over a range of building vintages and climates. This assessment will provide a solid foundation for future efforts that address the energy efficiency of large commercial duct systems in Title 24. This report describes our work to address Objective 1, which includes a review of past modeling efforts related to duct thermal performance, and recommends near- and long-term modeling approaches for analyzing duct thermal performance in large commercial buildings.

Wray, Craig P.

2003-10-01T23:59:59.000Z

119

International Conference on Ocean Energy, 6 October, Bilbao Computational Analysis of Ducted Turbine Performance  

E-Print Network [OSTI]

Turbine Performance M. Shives1 and C. Crawford2 Dept. of Mechanical Engineering, University of Victoria turbine designs using computational fluid dynamics (CFD) simulation. Analytical model coefficients is proposed for the base pressure coefficient. Keywords: base-pressure, CFD, diffuser-augmented turbine, tidal

Pedersen, Tom

120

TIDAL TURBULENCE SPECTRA FROM A COMPLIANT MOORING  

SciTech Connect (OSTI)

A compliant mooring to collect high frequency turbulence data at a tidal energy site is evaluated in a series of short demon- stration deployments. The Tidal Turbulence Mooring (TTM) improves upon recent bottom-mounted approaches by suspend- ing Acoustic Doppler Velocimeters (ADVs) at mid-water depths (which are more relevant to tidal turbines). The ADV turbulence data are superior to Acoustic Doppler Current Profiler (ADCP) data, but are subject to motion contamination when suspended on a mooring in strong currents. In this demonstration, passive stabilization is shown to be sufficient for acquiring bulk statistics of the turbulence, without motion correction. With motion cor- rection (post-processing), data quality is further improved; the relative merits of direct and spectral motion correction are dis- cussed.

Thomson, Jim; Kilcher, Levi; Richmond, Marshall C.; Talbert, Joe; deKlerk, Alex; Polagye, Brian; Guerra, Maricarmen; Cienfuegos, Rodrigo

2013-06-13T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Nitrogen Cycling and Ecosystem Exchanges in a Virginia Tidal Freshwater Marsh  

E-Print Network [OSTI]

loading due to watershed development and urbanization. We present a process-based mass balance model of N habitats for juvenile fishes, and buffering storm and flood waters (Odum et al. 1984; Mitsch and Gosselink dominated tidal freshwater marsh in the York River estuary, Virginia. The model, which was based

Neubauer, Scott C.

122

Measuring the Impact of Tidal Power Installations on Endangered...  

Energy Savers [EERE]

Renewable Power Company (ORPC) is conducting a two-year study on the effects of tidal turbines on endangered beluga whales in Cook Inlet, Alaska-home to some of the greatest tidal...

123

Fuel Cell Power Model for CHP and CHHP Economics and Performance Analysis (Presentation)  

SciTech Connect (OSTI)

This presentation describes the fuel cell power model for CHP and CHHP economics and performance analysis.

Steward, D.; Penev, M.

2010-03-30T23:59:59.000Z

124

Photovoltaic Array Condition Monitoring Based on Online Regression of Performance Model  

E-Print Network [OSTI]

Photovoltaic Array Condition Monitoring Based on Online Regression of Performance Model Sergiu Abstract -- Photovoltaic (PV) system performance can be degraded by a series of factors affecting the PV monitoring, fault detection, performance model, photovoltaic systems, regression analysis. I. INTRODUCTION

Teodorescu, Remus

125

Modeling Photovoltaic and Concentrating Solar Power Trough Performance, Cost, and Financing with Solar Advisor Model  

SciTech Connect (OSTI)

A comprehensive solar technology systems analysis model, the Solar Advisor Model (SAM), has been developed to support the federal R&D community and the solar industry by staff at the National Renewable Energy Laboratory (NREL) and Sandia National Laboratory. This model is able to model the finances, incentives, and performance of flat-plate photovoltaic (PV), concentrating PV, and concentrating solar power (specifically, parabolic troughs). The primary function of the model is to allow users to investigate the impact of variations in performance, cost, and financial parameters to better understand their impact on key figures of merit. Figures of merit related to the cost and performance of these systems include, but aren't limited to, system output, system efficiencies, levelized cost of energy, return on investment, and system capital and O&M costs. SAM allows users to do complex system modeling with an intuitive graphical user interface (GUI). In fact, all tables and graphics for this paper are taken directly from the model GUI. This model has the capability to compare different solar technologies within the same interface, making use of similar cost and finance assumptions. Additionally, the ability to do parametric and sensitivity analysis is central to this model. There are several models within SAM to model the performance of photovoltaic modules and inverters. This paper presents an overview of each PV and inverter model, introduces a new generic model, and briefly discusses the concentrating solar power (CSP) parabolic trough model. A comparison of results using the different PV and inverter models is also presented.

Blair, N.; Mehos, M.; Christensen, C.; Cameron, C.

2008-01-01T23:59:59.000Z

126

TIDAL FRESHWATER WETLANDS OF THE MID-ATLANTIC AND  

E-Print Network [OSTI]

Chapter 14 TIDAL FRESHWATER WETLANDS OF THE MID-ATLANTIC AND SOUTHEASTERN UNITED STATES James E Publishers, Weikersheim, 2009 Tidal Freshwater Wetlands, edited by Aat Barendregt in the book ,,Tidal Freshwater Wetlands". The copy attached is provided by Margraf Publishers Gmb

Newman, Michael C.

127

A Bayesian Approach to Online Performance Modeling for Database Appliances using Gaussian Models  

E-Print Network [OSTI]

agreements (SLAs) and to maintain peak performance for database management systems (DBMS), database, and resource provisioning. Accurately predicting response times of DBMS queries is necessary for a DBA an efficient and highly ac- curate online DBMS performance model that is robust in the face of changing

Waterloo, University of

128

A Bayesian Approach to Online Performance Modeling for Database Appliances using Gaussian Models  

E-Print Network [OSTI]

- tain peak performance for database management systems (DBMS), database administrators (DBAs) need. Accurately predicting response times of DBMS queries is necessary for a DBA to effectively achieve and highly accurate online DBMS performance model that is robust in the face of changing workloads, data

Aboulnaga, Ashraf

129

Numerical study of the diapycnal flow through a tidal front with passive tracers  

E-Print Network [OSTI]

. This qualitatively agrees with a recent field experiment using a dye tracer on Georges Bank. Additional experiments are performed to investigate the sensitivity of the tracer dispersion to the tidal phase and the location, the previous studies indicated Eulerian cross-front mean circu- lation maybe is in a multiple-cell structure

Dong, Changming "Charles"

130

Stochastic PV performance/reliability model : preview of alpha version.  

SciTech Connect (OSTI)

Problem Statement: (1) Uncertainties in PV system performance and reliability impact business decisions - Project cost and financing estimates, Pricing service contracts and guarantees, Developing deployment and O&M strategies; (2) Understanding and reducing these uncertainties will help make the PV industry more competitive (3) Performance has typically been estimated without much attention to reliability of components; and (4) Tools are needed to assess all inputs to the value proposition (e.g., LCOE, cash flow, reputation, etc.). Goals and objectives are: (1) Develop a stochastic simulation model (in GoldSim) that can represent PV system performance as a function of system design, weather, reliability, and O&M policies; (2) Evaluate performance for an example system to quantify sources of uncertainty and identify dominant parameters via a sensitivity study; and (3) Example System - 1 inverter, 225 kW DC Array latitude tilt (90 strings of 12 modules {l_brace}1080 modules{r_brace}), Weather from Tucumcari, NM (TMY2 with annual uncertainty).

Stein, Joshua S.; Miller, Steven P.

2010-03-01T23:59:59.000Z

131

TIDAL DISRUPTION FLARES: THE ACCRETION DISK PHASE  

SciTech Connect (OSTI)

The evolution of an accretion disk, formed as a consequence of the disruption of a star by a black hole, is followed by solving numerically hydrodynamic equations. The present investigation aims to study the dependence of resulting light curves on dynamical and physical properties of such a transient disk during its existence. One of the main results derived from our simulations is that blackbody fits of X-ray data tend to overestimate the true mean disk temperature. In fact, the temperature derived from blackbody fits should be identified with the color X-ray temperature rather than the average value derived from the true temperature distribution along the disk. The time interval between the beginning of the circularization of the bound debris and the beginning of the accretion process by the black hole is determined by the viscous (or accretion) timescale, which also fixes the rising part of the resulting light curve. The luminosity peak coincides with the beginning of matter accretion by the black hole and the late evolution of the light curve depends on the evolution of the debris fallback rate. Peak bolometric luminosities are in the range 10{sup 45}-10{sup 46} erg s{sup -1}, whereas peak luminosities in soft X-rays (0.2-2.0 keV) are typically one order of magnitude lower. The typical timescale derived from our preferred models for the flare luminosity to decay by two orders of magnitude is about 3-4 yr. Predicted soft X-ray light curves reproduce quite well data on galaxies in which a variable X-ray emission possibly related to a tidal event was detected. In the cases of NGC 3599 and IC 3599, data are reproduced well by models defined by a black hole with mass {approx}10{sup 7} M{sub sun} and a disrupted star of about 1 solar mass. The X-ray variation observed in XMMSL1 is consistent with a model defined by a black hole with mass {approx}3 x 10{sup 6} M{sub sun} and a disrupted star of 1 solar mass, while that observed in the galaxy situated in the cluster A1689 is consistent with a model including a black hole of {approx}10{sup 7} M{sub sun} and a disrupted star of {approx}0.5 M{sub sun}.

Montesinos Armijo, Matias; De Freitas Pacheco, Jose A. [Observatoire de la Cote d'Azur, Laboratoire Cassiopee, Universite de Nice Sophia-Antipolis Bd de l'Observatoire, BP 4229, 06304 Nice Cedex 4 (France)

2011-08-01T23:59:59.000Z

132

PERFORMANCE MODELING OF DAYLIGHT INTEGRATED PHOTOSENSOR- CONTROLLED LIGHTING SYSTEMS  

E-Print Network [OSTI]

Some building energy codes now require the incorporation of daylight into buildings and automatic photosensor-controlled switching or dimming of the electric lighting system in areas that receive daylight. This paper describes enhancements to the open-source Daysim daylight analysis software that permit users to model a photosensor control system as it will perform in a real space, considering the directional sensitivity of the photosensor, its mounting position, the space and daylight aperture geometry, window shading configuration; the electric lighting equipment and control zones; exterior obstructions; and site weather conditions. System output includes assessment of the daylight distribution in a space throughout the year, the photosensor’s ability to properly track the daylight and modify electric lighting system output, and the energy savings provided by the modeled control system. The application of daylight coefficients permits annual simulations to be conducted efficiently using hourly or finer weather data time increments. 1

S. Jain; R. R. Creasey; J. Himmelspach; K. P. White; M. Fu; Richard G. Mistrick

133

THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL  

SciTech Connect (OSTI)

The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. The Pena Blanca Natural Analogue Performance Assessment Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash-flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following analogous characteristics as compared to the Yucca Mountain repository site: (1) Analogous source--UO{sub 2} uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geology--(i.e. fractured, welded, and altered rhyolitic ash-flow tuffs); (3) Analogous climate--Semiarid to arid; (4) Analogous setting--Volcanic tuffs overlie carbonate rocks; and (5) Analogous geochemistry--Oxidizing conditions Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table.

G. Saulnier and W. Statham

2006-04-16T23:59:59.000Z

134

Control of household refrigerators. Part 1: Modeling temperature control performance  

SciTech Connect (OSTI)

Commercial household refrigerators use simple, cost-effective, temperature controllers to obtain acceptable control. A manually adjusted airflow damper regulates the freezer compartment temperature while a thermostat controls operation of the compressor and evaporator fan to regulate refrigerator compartment temperature. Dual compartment temperature control can be achieved with automatic airflow dampers that function independently of the compressor and evaporator fan thermostat, resulting in improved temperature control quality and energy consumption. Under dual control, freezer temperature is controlled by the thermostat while the damper controls refrigerator temperature by regulating airflow circulation. A simulation model is presented that analyzes a household refrigerator configured with a conventional thermostat and both manual and automatic dampers. The model provides a new paradigm for investigating refrigerator systems and temperature control performance relative to the extensive verification testing that is typically done by manufacturers. The effects of each type of control and damper configuration are compared with respect to energy usage, control quality, and ambient temperature shift criteria. The results indicate that the appropriate control configuration can have significant effects and can improve plant performance.

Graviss, K.J.; Collins, R.L.

1999-07-01T23:59:59.000Z

135

A numerical study of horizontal dispersion in a macro tidal basin  

E-Print Network [OSTI]

in Cobscook Bay, a macro tidal basin, is simulated using the three-dimensional, nonlinear, finite element regimes in different parts of Cobscook Bay. It is found that the effective Lagrangian dispersion ocean model, QUODDY_dry. Numerical particles are released from various transects in the bay at different

Maine, University of

136

An analytical solution of groundwater response to tidal fluctuation in a leaky confined aquifer  

E-Print Network [OSTI]

of China. 1. Introduction In most coastal areas, groundwater and seawater are in con- stant communicationAn analytical solution of groundwater response to tidal fluctuation in a leaky confined aquifer Jiu of the solution presented in this paper. This solution is based on a conceptual model under the assumption

Jiao, Jiu Jimmy

137

Tidal mixing around the Maritime continent: implications for1 paleoclimate simulations2  

E-Print Network [OSTI]

of mechanical energy for the ocean circulation and as such is 6 being incorporated changes in the ocean thermal structure, including 12 a ~1o C warming into state-of-the-art climate models. Calculation of the tidal energy flux depends on 7

138

Direct-Steam Linear Fresnel Performance Model for NREL's System Advisor Model  

SciTech Connect (OSTI)

This paper presents the technical formulation and demonstrated model performance results of a new direct-steam-generation (DSG) model in NREL's System Advisor Model (SAM). The model predicts the annual electricity production of a wide range of system configurations within the DSG Linear Fresnel technology by modeling hourly performance of the plant in detail. The quasi-steady-state formulation allows users to investigate energy and mass flows, operating temperatures, and pressure drops for geometries and solar field configurations of interest. The model includes tools for heat loss calculation using either empirical polynomial heat loss curves as a function of steam temperature, ambient temperature, and wind velocity, or a detailed evacuated tube receiver heat loss model. Thermal losses are evaluated using a computationally efficient nodal approach, where the solar field and headers are discretized into multiple nodes where heat losses, thermal inertia, steam conditions (including pressure, temperature, enthalpy, etc.) are individually evaluated during each time step of the simulation. This paper discusses the mathematical formulation for the solar field model and describes how the solar field is integrated with the other subsystem models, including the power cycle and optional auxiliary fossil system. Model results are also presented to demonstrate plant behavior in the various operating modes.

Wagner, M. J.; Zhu, G.

2012-09-01T23:59:59.000Z

139

Computational Human Performance Modeling For Alarm System Design  

SciTech Connect (OSTI)

The introduction of new technologies like adaptive automation systems and advanced alarms processing and presentation techniques in nuclear power plants is already having an impact on the safety and effectiveness of plant operations and also the role of the control room operator. This impact is expected to escalate dramatically as more and more nuclear power utilities embark on upgrade projects in order to extend the lifetime of their plants. One of the most visible impacts in control rooms will be the need to replace aging alarm systems. Because most of these alarm systems use obsolete technologies, the methods, techniques and tools that were used to design the previous generation of alarm system designs are no longer effective and need to be updated. The same applies to the need to analyze and redefine operators’ alarm handling tasks. In the past, methods for analyzing human tasks and workload have relied on crude, paper-based methods that often lacked traceability. New approaches are needed to allow analysts to model and represent the new concepts of alarm operation and human-system interaction. State-of-the-art task simulation tools are now available that offer a cost-effective and efficient method for examining the effect of operator performance in different conditions and operational scenarios. A discrete event simulation system was used by human factors researchers at the Idaho National Laboratory to develop a generic alarm handling model to examine the effect of operator performance with simulated modern alarm system. It allowed analysts to evaluate alarm generation patterns as well as critical task times and human workload predicted by the system.

Jacques Hugo

2012-07-01T23:59:59.000Z

140

Puget Sound Tidal Energy In-Water Testing and Development Project Final Technical Report  

SciTech Connect (OSTI)

Tidal energy represents potential for the generation of renewable, emission free, environmentally benign, and cost effective energy from tidal flows. A successful tidal energy demonstration project in Puget Sound, Washington may enable significant commercial development resulting in important benefits for the northwest region and the nation. This project promoted the United States Department of Energy�s Wind and Hydropower Technologies Program�s goals of advancing the commercial viability, cost-competitiveness, and market acceptance of marine hydrokinetic systems. The objective of the Puget Sound Tidal Energy Demonstration Project is to conduct in-water testing and evaluation of tidal energy technology as a first step toward potential construction of a commercial-scale tidal energy power plant. The specific goal of the project phase covered by this award was to conduct all activities necessary to complete engineering design and obtain construction approvals for a pilot demonstration plant in the Admiralty Inlet region of the Puget Sound. Public Utility District No. 1 of Snohomish County (The District) accomplished the objectives of this award through four tasks: Detailed Admiralty Inlet Site Studies, Plant Design and Construction Planning, Environmental and Regulatory Activities, and Management and Reporting. Pre-Installation studies completed under this award provided invaluable data used for site selection, environmental evaluation and permitting, plant design, and construction planning. However, these data gathering efforts are not only important to the Admiralty Inlet pilot project. Lessons learned, in particular environmental data gathering methods, can be applied to future tidal energy projects in the United States and other parts of the world. The District collaborated extensively with project stakeholders to complete the tasks for this award. This included Federal, State, and local government agencies, tribal governments, environmental groups, and others. All required permit and license applications were completed and submitted under this award, including a Final License Application for a pilot hydrokinetic license from the Federal Energy Regulatory Commission. The tasks described above have brought the project through all necessary requirements to construct a tidal pilot project in Admiralty Inlet with the exception of final permit and license approvals, and the selection of a general contractor to perform project construction.

Craig W. Collar

2012-11-16T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Sandia National Laboratories: 2013 PV Performance Modeling Workshop  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Generator Modeling Radar Friendly Blades Special Programs Techno-Economic Modeling, Analysis, and Support Analysis, Modeling, Cost of Energy, and Policy Impact: Wind Vision 2014...

142

Development of a Model Specification for Performance Monitoring Systems for Commercial Buildings  

E-Print Network [OSTI]

Development of a Model Specification for Performance Monitoring Systems for Commercial Buildings the development of a model specification for performance monitoring systems for commercial buildings capabilities in #12;commercial buildings by demonstrating the capabilities of commercially available technology

143

Active Flow Control on Bidirectional Rotors for Tidal MHK Applications  

SciTech Connect (OSTI)

A marine and hydrokinetic (MHK) tidal turbine extracts energy from tidal currents, providing clean, sustainable electricity generation. In general, all MHK conversion technologies are confronted with significant operational hurdles, resulting in both increased capital and operations and maintenance (O&M) costs. To counter these high costs while maintaining reliability, MHK turbine designs can be simplified. Prior study found that a tidal turbine could be cost-effectively simplified by removing blade pitch and rotor/nacelle yaw. Its rotor would run in one direction during ebb and then reverse direction when the current switched to flood. We dubbed such a turbine a bidirectional rotor tidal turbine (BRTT). The bidirectional hydrofoils of a BRTT are less efficient than conventional hydrofoils and capture less energy, but the elimination of the pitch and yaw systems were estimated to reduce levelized cost of energy by 7.8%-9.6%. In this study, we investigated two mechanisms for recapturing some of the performance shortfall of the BRTT. First, we developed a novel set of hydrofoils, designated the yy series, for BRTT application. Second, we investigated the use of active flow control via microtabs. Microtabs are small deployable/retractable tabs, typically located near the leading or trailing edge of an air/hydrofoil with height on the order of the boundary layer thickness (1% - 2% of chord). They deploy approximately perpendicularly to the foil surface and, like gurney flaps and plain flaps, globally affect the aerodynamics of the airfoil. By strategically placing microtabs and selectively deploying them based on the direction of the inflow, performance of a BRTT rotor can be improved while retaining bidirectional operation. The yy foils were computationally designed and analyzed. They exhibited better performance than the baseline bidirectional foil, the ellipse. For example, the yyb07cn-180 had 14.7% higher (l/d)max than an ellipse of equal thickness. The yyb07cn family also had higher c{sub p,min} than equivalently thick ellipses, indicating less susceptibility to cavitation. Microtabs applied on yy foils demonstrated improved energy capture. A series of variable speed and constant speed rotors were developed with the yyb07cn family of hydrofoils. The constant speed yyb07cn rotor (yy-B02-Rcs,opt) captured 0.45% more energy than the equivalent rotor with ellipses (e-B02-Rcs,opt). With microtabs deployed (yy?t-B02-Rcs,opt), the energy capture increase over the rotor with ellipses was 1.05%. Note, however, that microtabs must be applied judiciously to bidirectional foils. On the 18% thick ellipse, performance decreased with the addition of microtabs. Details of hydrofoil performance, microtab sizing and positioning, rotor configurations, and revenue impacts are presented herein.

Shiu, Henry [Research Engineer; van Dam, Cornelis P. [Professor

2013-08-22T23:59:59.000Z

144

Mon. Not. R. Astron. Soc. 391, 237245 (2008) doi:10.1111/j.1365-2966.2008.13868.x Tidal heating of terrestrial extrasolar planets and implications for their  

E-Print Network [OSTI]

these issues, we model the tidal heating and evolution of hypothetical extrasolar terrestrial planets, Greenberg & Barnes 2008b). If such a planet is on an eccentric orbit, the dissipation of tidal energy within extrasolar planets are observed to be larger than theoretical modelling predicts (e.g. Bodenheimer, E

Barnes, Rory

145

Tidal Interactions and Disruptions of Giant Planets on Highly Eccentric Orbits  

E-Print Network [OSTI]

We calculate the evolution of planets undergoing a strong tidal encounter using smoothed particle hydrodynamics (SPH), for a range of periastron separations. We find that outside the Roche limit, the evolution of the planet is well-described by the standard model of linear, non-radial, adiabatic oscillations. If the planet passes within the Roche limit at periastron, however, mass can be stripped from it, but in no case do we find enough energy transferred to the planet to lead to complete disruption. In light of the three new extrasolar planets discovered with periods shorter than two days, we argue that the shortest-period cases observed in the period-mass relation may be explained by a model whereby planets undergo strong tidal encounters with stars, after either being scattered by dynamical interactions into highly eccentric orbits, or tidally captured from nearly parabolic orbits. Although this scenario does provide a natural explanation for the edge found for planets at twice the Roche limit, it does not explain how such planets will survive the inevitable expansion that results from energy injection during tidal circularization.

Joshua A. Faber; Frederic A. Rasio; Bart Willems

2004-11-15T23:59:59.000Z

146

Circularization of Tidally Disrupted Stars around Spinning Supermassive Black Holes  

E-Print Network [OSTI]

We study the circularization of tidally disrupted stars on bound orbits around spinning supermassive black holes by performing three-dimensional smoothed particle hydrodynamic simulations with Post-Newtonian corrections. Our simulations reveal that debris circularization depends sensitively on the efficiency of radiative cooling. There are two stages in debris circularization if radiative cooling is inefficient: first, the stellar debris streams self-intersect due to relativistic apsidal precession; shocks at the intersection points thermalize orbital energy and the debris forms a geometrically thick, ring-like structure around the black hole. The ring rapidly spreads via viscous diffusion, leading to the formation of a geometrically thick accretion disk. In contrast, if radiative cooling is efficient, the stellar debris circularizes due to self-intersection shocks and forms a geometrically thin ring-like structure. In this case, the dissipated energy can be emitted during debris circularization as a precurso...

Hayasaki, Kimitake; Loeb, Abraham

2015-01-01T23:59:59.000Z

147

Using Machine Learning to Create Turbine Performance Models (Presentation)  

SciTech Connect (OSTI)

Wind turbine power output is known to be a strong function of wind speed, but is also affected by turbulence and shear. In this work, new aerostructural simulations of a generic 1.5 MW turbine are used to explore atmospheric influences on power output. Most significant is the hub height wind speed, followed by hub height turbulence intensity and then wind speed shear across the rotor disk. These simulation data are used to train regression trees that predict the turbine response for any combination of wind speed, turbulence intensity, and wind shear that might be expected at a turbine site. For a randomly selected atmospheric condition, the accuracy of the regression tree power predictions is three times higher than that of the traditional power curve methodology. The regression tree method can also be applied to turbine test data and used to predict turbine performance at a new site. No new data is required in comparison to the data that are usually collected for a wind resource assessment. Implementing the method requires turbine manufacturers to create a turbine regression tree model from test site data. Such an approach could significantly reduce bias in power predictions that arise because of different turbulence and shear at the new site, compared to the test site.

Clifton, A.

2013-04-01T23:59:59.000Z

148

Accelerating Energy Savings Performance Contracting Through Model Statewide Programs  

Broader source: Energy.gov [DOE]

Provides suggestions on how to accelerateEnergy Savings Performance Contracting programs and information about the types of assistance provided under the 'Accelerated Energy Savings Performance Contracting' initiative. Author: Energy Services Coalition

149

Regulation of Tidal and Wave Energy Projects (Maine)  

Broader source: Energy.gov [DOE]

State regulation of tidal and wave energy projects is covered under the Maine Waterway Development and Conservation Act (MWDCA), and complements regulation by the Federal Energy Regulation...

150

All Eyes on Eastport: Tidal Energy Project Brings Change, Opportunity...  

Office of Environmental Management (EM)

Ocean Renewable Power Company will unveil its first commercial-scale tidal turbine before it is deployed underwater to generate power. The pilot project -- supported by...

151

Temperature and Tidal Dynamics in a Branching Estuarine System  

E-Print Network [OSTI]

Importance of the Interconnectivity of Branching ChannelsImportance of the Interconnectivity of Branching Channels Inquestions about tidal interconnectivity in the Sacramento-

Wagner, Richard Wayne

2012-01-01T23:59:59.000Z

152

Assessment of Energy Production Potential from Tidal Streams...  

Office of Environmental Management (EM)

technology. 1023527.pdf More Documents & Publications EA-1949: FERC Draft Environmental Assessment EA-1949: FERC Final Environmental Assessment Tidal Energy Resource Assessment...

153

Summary Results for Brine Migration Modeling Performed by LANL...  

Office of Environmental Management (EM)

BrineMigrationModeling More Documents & Publications Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt Establishing the Technical Basis for...

154

THE EFFECT OF MASS LOSS ON THE TIDAL EVOLUTION OF EXTRASOLAR PLANET  

E-Print Network [OSTI]

By combining mass loss and tidal evolution of close-in planets, we present a qualitative study on their tidal migrations. We incorporate mass loss in tidal evolution for planets with different masses and find that mass ...

Guo, Jianheng

155

Tocardo Tidal Energy Ltd | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-gTaguspark JumpDetective: Terminology andInformationTocardo Tidal

156

Tidal Energy Resource Assessment | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyThe Sun and Its EnergyMetalofAgreement forTidal Energy

157

Tidal Energy Test Platform | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:Seadov Pty LtdSteen,Ltd Jump JumpAl., 1978) |Thrall,Tibagi Energetica Jump to:TidalTest

158

Performance of the Community Earth System Model | Argonne Leadership...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2011 Name of Publication Source: (SC), 2011 International Conference - High Performance Computing, Networking, Storage and Analysis Publisher: IEEE Explore Page Numbers: 1-11...

159

Performance and Portability of an Air Quality Model Donald Dabdub  

E-Print Network [OSTI]

and planning for the control of air pollution episodes. The California Institute of Technology (CIT) photochemical model is one such air quality model. It is used to predict the pollution dynamics in the South Coast Air Basin of California. It has also been modified to model pollution in South Korea, Mexico

Manohar, Rajit

160

Acoustic Monitoring of Beluga Whale Interactions with Cook Inlet Tidal Energy Project  

SciTech Connect (OSTI)

Cook Inlet, Alaska is home to some of the greatest tidal energy resources in the U.S., as well as an endangered population of beluga whales (Delphinapterus leucas). Successfully permitting and operating a tidal power project in Cook Inlet requires a biological assessment of the potential and realized effects of the physical presence and sound footprint of tidal turbines on the distribution, relative abundance, and behavior of Cook Inlet beluga whales. ORPC Alaska, working with the Project Team—LGL Alaska Research Associates, University of Alaska Anchorage, TerraSond, and Greeneridge Science—undertook the following U.S. Department of Energy (DOE) study to characterize beluga whales in Cook Inlet – Acoustic Monitoring of Beluga Whale Interactions with the Cook Inlet Tidal Energy Project (Project). ORPC Alaska, LLC, is a wholly-owned subsidiary of Ocean Renewable Power Company, LLC, (collectively, ORPC). ORPC is a global leader in the development of hydrokinetic power systems and eco-conscious projects that harness the power of ocean and river currents to create clean, predictable renewable energy. ORPC is developing a tidal energy demonstration project in Cook Inlet at East Foreland where ORPC has a Federal Energy Regulatory Commission (FERC) preliminary permit (P-13821). The Project collected baseline data to characterize pre-deployment patterns of marine mammal distribution, relative abundance, and behavior in ORPC’s proposed deployment area at East Foreland. ORPC also completed work near Fire Island where ORPC held a FERC preliminary permit (P-12679) until March 6, 2013. Passive hydroacoustic devices (previously utilized with bowhead whales in the Beaufort Sea) were adapted for study of beluga whales to determine the relative abundance of beluga whale vocalizations within the proposed deployment areas. Hydroacoustic data collected during the Project were used to characterize the ambient acoustic environment of the project site pre-deployment to inform the FERC pilot project process. The Project compared results obtained from this method to results obtained from other passive hydrophone technologies and to visual observation techniques performed simultaneously. This Final Report makes recommendations on the best practice for future data collection, for ORPC’s work in Cook Inlet specifically, and for tidal power projects in general. This Project developed a marine mammal study design and compared technologies for hydroacoustic and visual data collection with potential for broad application to future tidal and hydrokinetic projects in other geographic areas. The data collected for this Project will support the environmental assessment of future Cook Inlet tidal energy projects, including ORPC’s East Foreland Tidal Energy Project and any tidal energy developments at Fire Island. The Project’s rigorous assessment of technology and methodologies will be invaluable to the hydrokinetic industry for developing projects in an environmentally sound and sustainable way for areas with high marine mammal activity or endangered populations. By combining several different sampling methods this Project will also contribute to the future preparation of a comprehensive biological assessment of ORPC’s projects in Cook Inlet.

Worthington, Monty [Project Director - AK] [Project Director - AK

2014-02-05T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Case Studies Comparing System Advisor Model (SAM) Results to Real Performance Data: Preprint  

SciTech Connect (OSTI)

NREL has completed a series of detailed case studies comparing the simulations of the System Advisor Model (SAM) and measured performance data or published performance expectations. These case studies compare PV measured performance data with simulated performance data using appropriate weather data. The measured data sets were primarily taken from NREL onsite PV systems and weather monitoring stations.

Blair, N.; Dobos, A.; Sather, N.

2012-06-01T23:59:59.000Z

162

BLACK-BOX MODELLING OF HVAC SYSTEM: IMPROVING THE PERFORMANCES OF NEURAL NETWORKS  

E-Print Network [OSTI]

BLACK-BOX MODELLING OF HVAC SYSTEM: IMPROVING THE PERFORMANCES OF NEURAL NETWORKS Eric FOCK Ile de La Réunion - FRANCE ABSTRACT This paper deals with neural networks modelling of HVAC systems of HVAC system can be modelled using manufacturer design data presented as derived performance maps

Boyer, Edmond

163

Accelerating Energy Savings Performance Contracting Through Model Statewide Programs  

Broader source: Energy.gov [DOE]

Provides information on Energy Savings Performance Contracing (ESPC), including links to best practices and tools as well as the Accelerated ESCP initiative and types of assistance available. Author: Energy Services Coalition

164

An integrated performance model for high temperature gas cooled reactor coated particle fuel  

E-Print Network [OSTI]

The performance of coated fuel particles is essential for the development and deployment of High Temperature Gas Reactor (HTGR) systems for future power generation. Fuel performance modeling is indispensable for understanding ...

Wang, Jing, 1976-

2004-01-01T23:59:59.000Z

165

Fuel Cell Power Model for CHHP System Economics and Performance...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Fuel Cell Tri-Generation System Case Study using the H2A Stationary Model Stationary Fuel Cells: Overview of Hydrogen and Fuel Cell Activities Biogas Opportunities Roadmap...

166

Methodology for Modeling Building Energy Performance across the Commercial Sector  

SciTech Connect (OSTI)

This report uses EnergyPlus simulations of each building in the 2003 Commercial Buildings Energy Consumption Survey (CBECS) to document and demonstrate bottom-up methods of modeling the entire U.S. commercial buildings sector (EIA 2006). The ability to use a whole-building simulation tool to model the entire sector is of interest because the energy models enable us to answer subsequent 'what-if' questions that involve technologies and practices related to energy. This report documents how the whole-building models were generated from the building characteristics in 2003 CBECS and compares the simulation results to the survey data for energy use.

Griffith, B.; Long, N.; Torcellini, P.; Judkoff, R.; Crawley, D.; Ryan, J.

2008-03-01T23:59:59.000Z

167

WUFI COMPUTER MODELING WORKSHOP FOR WALL DESIGN AND PERFORMANCE  

E-Print Network [OSTI]

, building forensic specialists, manufacturer representatives, facilities managers, IAQ specialists of modeling for new products are demonstrated by both group and individual interaction. · You will learn how

Oak Ridge National Laboratory

168

Performance Modeling and Simulation Studies of MAC Protocols in Sensor Network Performance  

E-Print Network [OSTI]

tree R used for performance evaluation. II. ENERGY EFFICIENT WAKE-UP AND DATA COLLECTION Data Sahota Ratnesh Kumar Ahmed Kamal Dept. of Electrical and Computer Engineering, Iowa State University for the purpose of achieving energy savings. In addition, MAC layer is designed which uses these multiple power

Kumar, Ratnesh

169

Develop a numerical model to evaluate furrow irrigation performance  

E-Print Network [OSTI]

. The modified Kostiakov equation was utilized to describe the infiltration process. The model accurately predicted advance time. In three of the data sets the average absolute error of advance time was less than 5%. The model did a reasonably good job...

Jnad, Ihab

1996-01-01T23:59:59.000Z

170

Fuel Cell Power Model for CHHP System Economics and Performance Analysis (Presentation)  

SciTech Connect (OSTI)

Presentation about Fuel Cell Power (FCPower) Model used to analyze the economics and performance of combined heat, hydrogen, and power (CHHP) systems.

Steward, D.

2009-11-16T23:59:59.000Z

171

Roofline: An Insightful Visual Performance Model for Floating-Point Programs and Multicore Architectures  

SciTech Connect (OSTI)

We propose an easy-to-understand, visual performance model that offers insights to programmers and architects on improving parallel software and hardware for floating point computations.

Williams, Samuel; Waterman, Andrew; Patterson, David

2009-02-01T23:59:59.000Z

172

Analytical model and performance data for a cylindrical parabolic collector  

SciTech Connect (OSTI)

Concentrating solar collectors provide higher fluid temperatures than flat-plate, an important advantage in many applications. The parabolic cylinder is one of the most popular types of concentrating collectors because of its relatively simple construction and tracking configuration. A mathematical model was developed for one such collector in order to predict thermal efficiency as a function of solar insolation. An experiment was then devised in an attempt to verify this model. Discrepancies between predicted and observed values are discussed, and suggestions are made for improving the model and the experimental procedure.

Ford, F.M.; Stewart, W.E. Jr.

1980-01-01T23:59:59.000Z

173

An improved structural mechanics model for the FRAPCON nuclear fuel performance code  

E-Print Network [OSTI]

In order to provide improved predictions of Pellet Cladding Mechanical Interaction (PCMI) for the FRAPCON nuclear fuel performance code, a new model, the FRAPCON Radial-Axial Soft Pellet (FRASP) model, was developed. This ...

Mieloszyk, Alexander James

2012-01-01T23:59:59.000Z

174

Modeling the Impact of Product Portfolio on the Economic and Environmental Performance of Recycling Systems  

E-Print Network [OSTI]

hrough the development of a general model of electronics recycling systems, the effect of product portfolio choices on economic and environmental system performance is explored. The general model encompasses the three main ...

Dahmus, Jeffrey B.

175

Modeling of performance behavior in gas condensate reservoirs using a variable mobility concept  

E-Print Network [OSTI]

The proposed work provides a concept for predicting well performance behavior in a gas condensate reservoir using an empirical model for gas mobility. The proposed model predicts the behavior of the gas permeability (or mobility) function...

Wilson, Benton Wade

2004-09-30T23:59:59.000Z

176

Continuous-time model reference adaptive control with improved transient performance  

E-Print Network [OSTI]

. . 10 3. 1. Introduction . . 3. 2. Performance of a Standard MRAC Scheme. . . . . . . . . 3. 3. Performance Improvement as Input Disturbance Rejection 3. 4. A Modified MRAC Scheme for Improved Transient Per- formance . 3. 5. Example and Simulations... 10 13 16 21 24 IV MODEL REFERENCE ADAPTIVE CONTROL OF RIGID ROBOTS WITH IMPROVED TRANSIENT PERFORMANCE 27 4. 1. Introduction 4. 2. Performance of a Standard MRAC Scheme for a Robotic Manipulator . 4. 3. Performance Improvement as Input...

Ho, Ming-Tzu

1993-01-01T23:59:59.000Z

177

OPTIMIZATION AND PERFORMANCE MODELING OF STENCIL COMPUTATIONS ON MODERN MICROPROCESSORS  

E-Print Network [OSTI]

(PDE) solvers constitute a large fraction of scientific applications in such diverse areas as heat- tive finite-difference techniques, which sweep over a spatial grid, performing nearest neighbor the coefficients of the PDE for that data element. These operations are then used to build solvers that range from

178

Do Some Business Models Perform Better than Others? A Study of the 1000 Largest US  

E-Print Network [OSTI]

Do Some Business Models Perform Better than Others? A Study of the 1000 Largest US Firms Authors, the concept of business model remains seldom studied. This paper begins by defining a business model as what of business models (Creators, Distributors, Landlords and Brokers). Next, by considering the type of asset

179

Abstract--Eventually, prediction of transformer thermal performance for dynamic loading will be made using models  

E-Print Network [OSTI]

1 Abstract--Eventually, prediction of transformer thermal performance for dynamic loading will be made using models distilled from measure data, rather than models derived from transformer heat for measuring the acceptability of transformer thermal models. For a model to be acceptable, it must have

180

Design of a Multicriteria Performance Model for JIT systems  

E-Print Network [OSTI]

. Afiesimama Performance measurement systems are necessary to provide a problem-f inding and problem-solving pr ocess that will motivate people to make improvements. Recently, many productivity measurement methods have been developed. However, most of them... concentrate either on the utilization of resources or the perfor mance of employees without analyzing the simultaneous impact of the environment of production, the method of production, the people involved in the production of the product...

Coulibaly, Soma

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

EVOLUTION OF PLANETARY ORBITS WITH STELLAR MASS LOSS AND TIDAL DISSIPATION  

SciTech Connect (OSTI)

Intermediate mass stars and stellar remnants often host planets, and these dynamical systems evolve because of mass loss and tides. This paper considers the combined action of stellar mass loss and tidal dissipation on planetary orbits in order to determine the conditions required for planetary survival. Stellar mass loss is included using a so-called Jeans model, described by a dimensionless mass loss rate ? and an index ?. We use an analogous prescription to model tidal effects, described here by a dimensionless dissipation rate ? and two indices (q, p). The initial conditions are determined by the starting value of angular momentum parameter ?{sub 0} (equivalently, the initial eccentricity) and the phase ? of the orbit. Within the context of this model, we derive an analytic formula for the critical dissipation rate ?, which marks the boundary between orbits that spiral outward due to stellar mass loss and those that spiral inward due to tidal dissipation. This analytic result ? = ?(?, ?, q, p, ?{sub 0}, ?) is essentially exact for initially circular orbits and holds to within an accuracy of ?50% over the entire multi-dimensional parameter space, where the individual parameters vary by several orders of magnitude. For stars that experience mass loss, the stellar radius often displays quasi-periodic variations, which produce corresponding variations in tidal forcing; we generalize the calculation to include such pulsations using a semi-analytic treatment that holds to the same accuracy as the non-pulsating case. These results can be used in many applications, e.g., to predict/constrain properties of planetary systems orbiting white dwarfs.

Adams, Fred C. [Physics Department, University of Michigan, Ann Arbor, MI 48109 (United States)] [Physics Department, University of Michigan, Ann Arbor, MI 48109 (United States); Bloch, Anthony M. [Math Department, University of Michigan, Ann Arbor, MI 48109 (United States)] [Math Department, University of Michigan, Ann Arbor, MI 48109 (United States)

2013-11-10T23:59:59.000Z

182

Modeling Windows in Energy Plus with Simple Performance Indices  

E-Print Network [OSTI]

indices (U-factor, Solar Heat Gain Coefficient, and Visible Transmittance) to model the energy impacts, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily

183

18 Modeling high-performance HBTs D.L. Pulfrey  

E-Print Network [OSTI]

an acceptable base resistance. A short base width leads directly to an improved cut-off frequency, fT , which, when coupled with the lower base resistance, leads to an improved oscillation frequency, fmax. These consideration is also given to the incorporation of the compact model for JC into a large-signal equivalent

Pulfrey, David L.

184

Duct Thermal Performance Models for Large Commercial Buildings  

E-Print Network [OSTI]

Energy Technologies Division Indoor Environment Department Lawrence Berkeley National Laboratory Berkeley Secretary for Energy Efficiency and Renewable Energy, Building Technologies Program, of the U.S. Department) for his assistance in defining the duct surface heat transfer models described in the body of this report

185

Resource Sharing in Performance Models Vlastimil Babka, Martin Decky, and Petr Tuma  

E-Print Network [OSTI]

observed during the relatively isolated execution of benchmarks. Unless resource sharing is described shared resources [16,17,18,26,27,29] or points out the high cost of solving the performance model whenResource Sharing in Performance Models Vlastimil Babka, Martin Deck´y, and Petr T°uma Department

186

MODELING THE EFFECT OF FLOW FIELD DESIGN ON PEM FUEL CELL PERFORMANCE  

E-Print Network [OSTI]

MODELING THE EFFECT OF FLOW FIELD DESIGN ON PEM FUEL CELL PERFORMANCE Jeffrey Glandt, Sirivatch University of South Carolina Columbia, SC 29208 vanzee@engr.sc.edu Key words: PEM fuel cell, flow field or printed in its publications. #12;2 MODELING THE EFFECT OF FLOW FIELD DESIGN ON PEM FUEL CELL PERFORMANCE

Van Zee, John W.

187

Hybrid Model for Building Performance Diagnosis and Optimal Control  

E-Print Network [OSTI]

systems and subsystems in buildings commonly used for diagnostic reasoning (IEA Annex 25, 1996). The top-down approach uses performance measurements from higher levels to reason about possible lower-level causes of degradations to those higher level...://poet.lbl.gov/diag- workshop/proceedings House J.M. and Smith TF. (1991). Optimal control of a thermal system. ASHRAE Transactions, Vol.97(2):991-1001. IEA Annex 25. (1996). Building optimization and fault diagnosis source book, Eds. J. Hyv?rinen and S. K?rki, Technical...

Wang, S.; Xu, X.

2003-01-01T23:59:59.000Z

188

Performance and Degradation Modeling of Batteries | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department ofT ib l L d F SSalesOE0000652Grow YourPerformance Audit ofPlan FAQs

189

Modeling performance of horizontal, undulating, and multilateral wells  

E-Print Network [OSTI]

.2. 10 0 10 20 30 40 50 0 5 10 15 20 25 30 35 40 45 50 Productivity index from modified Furui's model P r o d u c t i v i t y i n d e x f r o m l i n e s o u r c e m o d e l . Fig. 2.2 Validation modified Furui?s model with line source... through the reservoir the error is less than 10% for isotropic reservoir. 0 20 40 60 80 100 0 1000 2000 3000 4000 5000 Well length, ft P r o d u c t i v i t y i n d e x , ( S T B / D ) / p s i...

Kamkom, Rungtip

2009-05-15T23:59:59.000Z

190

Atmospheric Climate Model Experiments Performed at Multiple Horizontal Resolutions  

SciTech Connect (OSTI)

This report documents salient features of version 3.3 of the Community Atmosphere Model (CAM3.3) and of three climate simulations in which the resolution of its latitude-longitude grid was systematically increased. For all these simulations of global atmospheric climate during the period 1980-1999, observed monthly ocean surface temperatures and sea ice extents were prescribed according to standard Atmospheric Model Intercomparison Project (AMIP) values. These CAM3.3 resolution experiments served as control runs for subsequent simulations of the climatic effects of agricultural irrigation, the focus of a Laboratory Directed Research and Development (LDRD) project. The CAM3.3 model was able to replicate basic features of the historical climate, although biases in a number of atmospheric variables were evident. Increasing horizontal resolution also generally failed to ameliorate the large-scale errors in most of the climate variables that could be compared with observations. A notable exception was the simulation of precipitation, which incrementally improved with increasing resolution, especially in regions where orography plays a central role in determining the local hydroclimate.

Phillips, T; Bala, G; Gleckler, P; Lobell, D; Mirin, A; Maxwell, R; Rotman, D

2007-12-21T23:59:59.000Z

191

analysing tidally induced: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Tidally-induced thermonuclear Supernovae Astrophysics (arXiv) Summary: We discuss the results of 3D simulations...

192

Hydrodynamic analysis of a vertical axis tidal current turbine   

E-Print Network [OSTI]

Tidal currents can be used as a predictable source of sustainable energy, and have the potential to make a useful contribution to the energy needs of the UK and other countries with such a resource. One of the technologies ...

Gretton, Gareth I.

2009-01-01T23:59:59.000Z

193

Geomorphic structure of tidal hydrodynamics in salt marsh creeks  

E-Print Network [OSTI]

of the tidal signal within the marsh area. Citation: Fagherazzi, S., M. Hannion, and P. D'Odorico (2008 by elegant hydrological and geomorphological theories [Gupta et al., 1980; Rodriguez-Iturbe and Valdes, 1979

Fagherazzi, Sergio

194

On tidal capture of primordial black holes by neutron stars  

E-Print Network [OSTI]

The fraction of primordial black holes (PBHs) of masses $10^{17} - 10^{26}$ g in the total amount of dark matter may be constrained by considering their capture by neutron stars (NSs), which leads to the rapid destruction of the latter. The constraints depend crucially on the capture rate which, in turn, is determined by the energy loss by a PBH passing through a NS. Two alternative approaches to estimate the energy loss have been used in the literature: the one based on the dynamical friction mechanism, and another on tidal deformations of the NS by the PBH. The second mechanism was claimed to be more efficient by several orders of magnitude due to the excitation of particular oscillation modes reminiscent of the surface waves. We address this disagreement by considering a simple analytically solvable model that consists of a flat incompressible fluid in an external gravitational field. In this model, we calculate the energy loss by a PBH traversing the fluid surface. We find that the excitation of modes with the propagation velocity smaller than that of PBH is suppressed, which implies that in a realistic situation of a supersonic PBH the large contributions from the surface waves are absent and the above two approaches lead to consistent expressions for the energy loss.

Guillaume Defillon; Etienne Granet; Petr Tinyakov; Michel H. G. Tytgat

2014-09-01T23:59:59.000Z

195

Sensitivity of Concentrating Solar Power Trough Performance, Cost and Financing with Solar Advisor Model  

SciTech Connect (OSTI)

A comprehensive solar technology systems analysis model, the Solar Advisor Model (SAM) was developed to support the federal R&D community and the solar industry. This model, developed by staff at NREL and Sandia National Laboratory, is able to model the costs, finances, and performance of concentrating solar power and photovoltaics (PV). Currently, parabolic troughs and concentrating PV are the two concentrating technologies modeled within the SAM environment.

Blair, N.; Mehos, M.; Christensen, C.

2008-03-01T23:59:59.000Z

196

Modeling Photovoltaic and Concentrating Solar Power Trough Performance, Cost, and Financing with the Solar Advisor Model: Preprint  

SciTech Connect (OSTI)

A comprehensive solar technology systems analysis model, the Solar Advisor Model (SAM), has been developed to support the federal R&D community and the solar industry by staff at the National Renewable Energy Laboratory (NREL) and Sandia National Laboratory. This model is able to model the finances, incentives, and performance of flat-plate photovoltaic (PV), concentrating PV, and concentrating solar power (specifically, parabolic troughs). The primary function of the model is to allow users to investigate the impact of variations in performance, cost, and financial parameters to better understand their impact on key figures of merit. Figures of merit related to the cost and performance of these systems include, but aren't limited to, system output, system efficiencies, levelized cost of energy, return on investment, and system capital and O&M costs. There are several models within SAM to model the performance of photovoltaic modules and inverters. This paper presents an overview of each PV and inverter model, introduces a new generic model, and briefly discusses the concentrating solar power (CSP) parabolic trough model. A comparison of results using the different PV and inverter models is also presented.

Blair, N.; Mehos, M.; Christensen, C.; Cameron, C.

2008-05-01T23:59:59.000Z

197

Interactions Between Tidal Flows and Ooid Shoals, Northern Bahamas  

E-Print Network [OSTI]

active sand waves and ripples. Towards the platform margin, tidal currents pass through narrow inlets. The main inlet opening oceanward (NW) of the shoal stretches between two Pleistocene bedrock islands, connected by a bedrock high that extends... include both flood and ebb tidal deltas, with generally lobate forms, convex away from the islands, and with endpoints at the inlets. Although the inner portions of these lobes are mainly seagrass-stabilized muddy peloidal and skeletal sands with local...

Reeder, Stacy Lynn; Rankey, Gene C.

2008-03-01T23:59:59.000Z

198

GRB060218 AS A TIDAL DISRUPTION OF A WHITE DWARF BY AN INTERMEDIATE-MASS BLACK HOLE  

SciTech Connect (OSTI)

The highly unusual pair of a gamma-ray burst (GRB) GRB060218 and an associated supernova, SN2006aj, has puzzled theorists for years. A supernova shock breakout and a jet from a newborn stellar mass compact object have been proposed to explain this pair's multiwavelength signature. Alternatively, we propose that the source is naturally explained by another channel: the tidal disruption of a white dwarf (WD) by an intermediate-mass black hole (IMBH). This tidal disruption is accompanied by a tidal pinching, which leads to the ignition of a WD and a supernova. Some debris falls back onto the IMBH, forms a disk, which quickly amplifies the magnetic field, and launches a jet. We successfully fit soft X-ray spectra with the Comptonized blackbody emission from a jet photosphere. The optical/UV emission is consistent with self-absorbed synchrotron emission from the expanding jet front. The temporal dependence of the accretion rate M-dot (t) in a tidal disruption provides a good fit to the soft X-ray light curve. The IMBH mass is found to be about 10{sup 4} M{sub Sun} in three independent estimates: (1) fitting the tidal disruption M-dot (t) to the soft X-ray light curve, (2) computing the jet base radius in a jet photospheric emission model, and (3) inferring the mass of the central black hole based on the host dwarf galaxy's stellar mass. The position of the supernova is consistent with the center of the host galaxy, while the low supernova ejecta mass is consistent with that of a WD. The high expected rate of tidal disruptions in dwarf galaxies is consistent with one source observed by the Swift satellite over several years at a distance of 150 Mpc measured for GRB060218. Encounters with WDs provide much fuel for the growth of IMBHs.

Shcherbakov, Roman V.; Reynolds, Christopher S. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Pe'er, Asaf [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Haas, Roland [Theoretical AstroPhysics Including Relativity, California Institute of Technology, Pasadena, CA 91125 (United States); Bode, Tanja; Laguna, Pablo [Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

2013-06-01T23:59:59.000Z

199

Accounting for the effects of rehabilitation actions on the reliability of flexible pavements: performance modeling and optimization  

E-Print Network [OSTI]

A performance model and a reliability-based optimization model for flexible pavements that accounts for the effects of rehabilitation actions are developed. The developed performance model can be effectively implemented in all the applications...

Deshpande, Vighnesh Prakash

2009-05-15T23:59:59.000Z

200

Results and Comparison from the SAM Linear Fresnel Technology Performance Model: Preprint  

SciTech Connect (OSTI)

This paper presents the new Linear Fresnel technology performance model in NREL's System Advisor Model. The model predicts the financial and technical performance of direct-steam-generation Linear Fresnel power plants, and can be used to analyze a range of system configurations. This paper presents a brief discussion of the model formulation and motivation, and provides extensive discussion of the model performance and financial results. The Linear Fresnel technology is also compared to other concentrating solar power technologies in both qualitative and quantitative measures. The Linear Fresnel model - developed in conjunction with the Electric Power Research Institute - provides users with the ability to model a variety of solar field layouts, fossil backup configurations, thermal receiver designs, and steam generation conditions. This flexibility aims to encompass current market solutions for the DSG Linear Fresnel technology, which is seeing increasing exposure in fossil plant augmentation and stand-alone power generation applications.

Wagner, M. J.

2012-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Nonrotating black hole in a post-Newtonian tidal environment  

E-Print Network [OSTI]

We examine the motion and tidal dynamics of a nonrotating black hole placed within a post-Newtonian external spacetime. The tidal perturbation created by the external environment is treated as a small perturbation. At a large distance from the black hole, the gravitational field of the external distribution of matter is assumed to be sufficiently weak to be adequately described by the (first) post-Newtonian approximation to general relativity. There, the black hole is treated as a monopole contribution to the total gravitational field. There exists an overlap in the domains of validity of each description, and the black-hole and post-Newtonian metrics are matched in the overlap. The matching procedure produces the equations of motion for the black hole and the gravito-electric and gravito-magnetic tidal fields acting on the black hole. We first calculate the equations of motion and tidal fields by making no assumptions regarding the nature of the post-Newtonian environment; this could contain a continuous distribution of matter or any number of condensed bodies. We next specialize our discussion to a situation in which the black hole is a member of a post-Newtonian two-body system. As an application of our results, we examine the geometry of the deformed event horizon and calculate the tidal heating of the black hole, the rate at which it acquires mass as a result of its tidal interaction with the companion body.

Stephanne Taylor; Eric Poisson

2008-09-11T23:59:59.000Z

202

Validated Model-Based Performance Prediction of Multi-Core Software Routers  

E-Print Network [OSTI]

Terms--measurement, simulation, intra-node model, re- source contention, model validation, software components. Leveraged by high flexibility and low costs of software developments in comparison with hardwareValidated Model-Based Performance Prediction of Multi-Core Software Routers Torsten Meyer1

Carle, Georg

203

A Simulation Model for the Performance Evaluation for Migrating a Legacy Paulo Pinheiro da Silva  

E-Print Network [OSTI]

A Simulation Model for the Performance Evaluation for Migrating a Legacy System Paulo Pinheiro da a simulation model using CAPPLES. Peculiarities of the legacy system migration that affects the simulation of perfor- mance evaluation during migration. CAPPLES is based on simulation models. Indeed, analytical

Pinheiro da Silva, Paulo

204

Supercomputer and cluster performance modeling and analysis efforts:2004-2006.  

SciTech Connect (OSTI)

This report describes efforts by the Performance Modeling and Analysis Team to investigate performance characteristics of Sandia's engineering and scientific applications on the ASC capability and advanced architecture supercomputers, and Sandia's capacity Linux clusters. Efforts to model various aspects of these computers are also discussed. The goals of these efforts are to quantify and compare Sandia's supercomputer and cluster performance characteristics; to reveal strengths and weaknesses in such systems; and to predict performance characteristics of, and provide guidelines for, future acquisitions and follow-on systems. Described herein are the results obtained from running benchmarks and applications to extract performance characteristics and comparisons, as well as modeling efforts, obtained during the time period 2004-2006. The format of the report, with hypertext links to numerous additional documents, purposefully minimizes the document size needed to disseminate the extensive results from our research.

Sturtevant, Judith E.; Ganti, Anand; Meyer, Harold (Hal) Edward; Stevenson, Joel O.; Benner, Robert E., Jr. (.,; .); Goudy, Susan Phelps; Doerfler, Douglas W.; Domino, Stefan Paul; Taylor, Mark A.; Malins, Robert Joseph; Scott, Ryan T.; Barnette, Daniel Wayne; Rajan, Mahesh; Ang, James Alfred; Black, Amalia Rebecca; Laub, Thomas William; Vaughan, Courtenay Thomas; Franke, Brian Claude

2007-02-01T23:59:59.000Z

205

Improvement of capabilities of the Distributed Electrochemistry Modeling Tool for investigating SOFC long term performance  

SciTech Connect (OSTI)

This report provides an overview of the work performed for Solid Oxide Fuel Cell (SOFC) modeling during the 2012 Winter/Spring Science Undergraduate Laboratory Internship at Pacific Northwest National Laboratory (PNNL). A brief introduction on the concept, operation basics and applications of fuel cells is given for the general audience. Further details are given regarding the modifications and improvements of the Distributed Electrochemistry (DEC) Modeling tool developed by PNNL engineers to model SOFC long term performance. Within this analysis, a literature review on anode degradation mechanisms is explained and future plans of implementing these into the DEC modeling tool are also proposed.

Gonzalez Galdamez, Rinaldo A.; Recknagle, Kurtis P.

2012-04-30T23:59:59.000Z

206

Structural Models and Endogeneity in Corporate Finance: The Link Between Managerial Ownership and Corporate Performance  

E-Print Network [OSTI]

This paper presents a parsimonious, structural model that isolates primary economic determinants of the level and dispersion of managerial ownership, firm scale, and performance and the empirical associations among them. ...

Coles, Jeffrey L.; Lemmon, Michael L.; Meschke, Felix

2012-01-01T23:59:59.000Z

207

Thermal mass performance in residential construction : an energy analysis using a cube model  

E-Print Network [OSTI]

Given the pervasiveness of energy efficiency concerns in the built environment, this research aims to answer key questions regarding the performance of thermal mass construction. The work presents the Cube Model, a simplified ...

Ledwith, Alison C. (Alison Catherine)

2012-01-01T23:59:59.000Z

208

Model studies to investigate the effects of fixed streamlines on water flooding performance  

E-Print Network [OSTI]

MODEL STUDIES TO INVESTIGATE THE EFFECTS OF FIXED STREAMLINES ON WATER FLOODING PERFORMANCE A Thesis by Axel Venton Green Submitted to the Graduate College of the Texas ASrM University in partial fulfillment of the requirements...

Green, Axel Venton

1964-01-01T23:59:59.000Z

209

Design optimization and analysis of coated particle fuel using advanced fuel performance modeling techniques  

E-Print Network [OSTI]

Modifying material properties provides another approach to optimize coated particle fuel used in pebble bed reactors. In this study, the MIT fuel performance model (TIMCOAT) was applied after benchmarking against the ...

Soontrapa, Chaiyod

2005-01-01T23:59:59.000Z

210

Systems, methods and computer-readable media for modeling cell performance fade of rechargeable electrochemical devices  

DOE Patents [OSTI]

A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware periodically samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics of the electrochemical cell. The computing system also develops a mechanistic level model of the electrochemical cell to determine performance fade characteristics of the electrochemical cell and analyzing the mechanistic level model to estimate performance fade characteristics over aging of a similar electrochemical cell. The mechanistic level model uses first constant-current pulses applied to the electrochemical cell at a first aging period and at three or more current values bracketing a first exchange current density. The mechanistic level model also is based on second constant-current pulses applied to the electrochemical cell at a second aging period and at three or more current values bracketing the second exchange current density.

Gering, Kevin L

2013-08-27T23:59:59.000Z

211

Modeling of Performance, Cost, and Financing of Concentrating Solar, Photovoltaic, and Solar Heat Systems (Poster)  

SciTech Connect (OSTI)

This poster, submitted for the CU Energy Initiative/NREL Symposium on October 3, 2006 in Boulder, Colorado, discusses the modeling, performance, cost, and financing of concentrating solar, photovoltaic, and solar heat systems.

Blair, N.; Mehos, M.; Christiansen, C.

2006-10-03T23:59:59.000Z

212

A stochastic model to mimic periodic surface currents in embayments  

E-Print Network [OSTI]

instruments are needing to accurately determine how the tide moves throughout the bay. In addition wind can pile up water in areas adding to the tidal height. Tidal currents are even more difficult to measure. Since wind along coasts is usually persistent... dynamics, some locations have very strong tidal currents (narrow straits or resonant bays). Elsewhere within an embayment, the tidal component may be a fraction of the total current, in any case, a wind-only current model will eventually diverge from...

Paternostro, Christopher Lee

2001-01-01T23:59:59.000Z

213

Development of a new model for predicting sucker-rod pumping system performance  

E-Print Network [OSTI]

DEVELOPMENT OF A NEW MODEL FOR PREDICTING SUCKER-ROD PUMPING SYSTEM PERFORMANCE A Thesis by JULIAN PEREZ GARCIA, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1988 Major Subject: Petroleum Engineering DEVELOPMENT OF A NEW MODEL FOR PREDICTING SUCKER-ROD PUMPING SYSTEM PERFORMANCE A Thesis by JULIAN PEREZ GARCIA, JR. Approved as to style and content by: J. . Jen in s (Cha...

Garcia, Julian Perez

1988-01-01T23:59:59.000Z

214

Genetic icing effects on forward flight performance of a model helicopter rotor  

E-Print Network [OSTI]

GENERIC ICING EFFECTS ON FORWARD FLIGHT PERFORMANCE OF A MODEL HELICOPTER ROTOR A Thesis ANA FIORELLA TINETTI-SANCHEZ Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1987 Major Subject: Aerospace Engineering GENERIC ICING EFFECTS ON FORWARD FLIGHT PERFORMANCE OF A MODEL HELICOPTER ROTOR A Thesis by ANA FIORELLA TINETTI-SANCHEZ Approved as to style and content by: Kenneth D. Korkan...

Tinetti-Sanchez, Ana Fiorella

1987-01-01T23:59:59.000Z

215

Effects of the Training Dataset Characteristics on the Performance of Nine Species Distribution Models  

E-Print Network [OSTI]

Effects of the Training Dataset Characteristics on the Performance of Nine Species Distribution species need to be fitted to a training dataset before practical use. The training dataset of this paper is to study the effect of the training dataset characteristics on model performance and to compare

Kratochvíl, Lukas

216

MEASUREMENTS OF FILM COOLING PERFORMANCE IN A TRANSONIC SINGLE PASSAGE MODEL  

E-Print Network [OSTI]

of film cooling on modern gas turbine blade geometries. By achieving this goal, the facility providedMEASUREMENTS OF FILM COOLING PERFORMANCE IN A TRANSONIC SINGLE PASSAGE MODEL by Paul M. Kodzwa, Jr #12;Abstract Film cooling is an essential technology for the development of high performance gas

Stanford University

217

TWO CHEMICAL SPILL PATTERNS IN TIDALLY  

E-Print Network [OSTI]

transport and multiple constituent eutrophication studies in a geographic context all from one application Model · Pollutant Transport Model · Eutrophication Model · All models use same computational grid

Chu, Peter C.

218

Integrated Estimation and Tracking of Performance Model Parameters with Autoregressive Trends  

E-Print Network [OSTI]

1 Integrated Estimation and Tracking of Performance Model Parameters with Autoregressive Trends Tao the model parameters can be tracked by an estimator such as a Kalman Filter, so that decisions can excessive cost (as is usually the case for the CPU time of a service). Because there may be significant

Woodside, C. Murray

219

Performance Modeling and Optimization of a High Energy CollidingBeam Simulation Code  

SciTech Connect (OSTI)

An accurate modeling of the beam-beam interaction is essential to maximizing the luminosity in existing and future colliders. BeamBeam3D was the first parallel code that can be used to study this interaction fully self-consistently on high-performance computing platforms. Various all-to-all personalized communication (AAPC) algorithms dominate its communication patterns, for which we developed a sequence of performance models using a series of micro-benchmarks. We find that for SMP based systems the most important performance constraint is node-adapter contention, while for 3D-Torus topologies good performance models are not possible without considering link contention. The best average model prediction error is very low on SMP based systems with of 3% to 7%. On torus based systems errors of 29% are higher but optimized performance can again be predicted within 8% in some cases. These excellent results across five different systems indicate that this methodology for performance modeling can be applied to a large class of algorithms.

Shan, Hongzhang; Strohmaier, Erich; Qiang, Ji; Bailey, David H.; Yelick, Kathy

2006-06-01T23:59:59.000Z

220

User's manual for heat-pump seasonal-performance model (SPM) with selected parametric examples  

SciTech Connect (OSTI)

The Seasonal Performance Model (SPM) was developed to provide an accurate source of seasonal energy consumption and cost predictions for the evaluation of heat pump design options. The program uses steady state heat pump performance data obtained from manufacturers' or Computer Simulation Model runs. The SPM was originally developed in two forms - a cooling model for central air conditioners and heat pumps and a heating model for heat pumps. The original models have undergone many modifications, which are described, to improve the accuracy of predictions and to increase flexibility for use in parametric evaluations. Insights are provided into the theory and construction of the major options, and into the use of the available options and output variables. Specific investigations provide examples of the possible applications of the model. (LEW)

Not Available

1982-06-30T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Systems, methods and computer-readable media to model kinetic performance of rechargeable electrochemical devices  

DOE Patents [OSTI]

A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics. The computing system also analyzes the cell information of the electrochemical cell with a Butler-Volmer (BV) expression modified to determine exchange current density of the electrochemical cell by including kinetic performance information related to pulse-time dependence, electrode surface availability, or a combination thereof. A set of sigmoid-based expressions may be included with the modified-BV expression to determine kinetic performance as a function of pulse time. The determined exchange current density may be used with the modified-BV expression, with or without the sigmoid expressions, to analyze other characteristics of the electrochemical cell. Model parameters can be defined in terms of cell aging, making the overall kinetics model amenable to predictive estimates of cell kinetic performance along the aging timeline.

Gering, Kevin L.

2013-01-01T23:59:59.000Z

222

User's Manual for Data for Validating Models for PV Module Performance  

SciTech Connect (OSTI)

This user's manual describes performance data measured for flat-plate photovoltaic (PV) modules installed in Cocoa, Florida, Eugene, Oregon, and Golden, Colorado. The data include PV module current-voltage curves and associated meteorological data for approximately one-year periods. These publicly available data are intended to facilitate the validation of existing models for predicting the performance of PV modules, and for the development of new and improved models. For comparing different modeling approaches, using these public data will provide transparency and more meaningful comparisons of the relative benefits.

Marion, W.; Anderberg, A.; Deline, C.; Glick, S.; Muller, M.; Perrin, G.; Rodriguez, J.; Rummel, S.; Terwilliger, K.; Silverman, T. J.

2014-04-01T23:59:59.000Z

223

Training Quench Performance and Quench Location of the Short Superconducting Dipole Models for the LHC  

E-Print Network [OSTI]

The short model program, started in October 1995 to study and validate design variants and assembly of the main LHC dipoles, has achieved its last phase. The last models were focused on the validation of specific design choices to be implemented in the series production, and to the study of the training performance of the coil heads. This paper reports on the manufacturing features of the recent twin-aperture short models, reviews the results of the cold tests and presents a summary of the training quench performance and quench location.

Sanfilippo, S; Tommasini, D; Venturini-Delsolaro, W

2002-01-01T23:59:59.000Z

224

Observational Learning of a Bimanual Coordination Task: Understanding Movement Feature Extraction, Model Performance Level, and Perspective Angle  

E-Print Network [OSTI]

offset between the two hands. Video recordings of two models practicing over three days were used to make three videos for the study; an expert performance, discovery performance, and instruction performance video. The discovery video portrayed a decrease...

Dean, Noah J.

2010-07-14T23:59:59.000Z

225

Les business models dans la distribution : reprer les chemins de la performance 1  

E-Print Network [OSTI]

1 Les business models dans la distribution : repérer les chemins de la performance 1 Pierre Volle peuvent être adressées à pierre.volle@dauphine.fr 2 Les business models dans la distribution : repérer les business model (BM) reste largement à préciser. L'objectif de cet article est donc de mettre en évidence

Paris-Sud XI, Université de

226

DETERMINATION OF ELECTROCHEMICAL PERFORMANCE, AND THERMO-MECHANICALCHEMICAL STABILITY OF SOFCS FROM DEFECT MODELING  

SciTech Connect (OSTI)

The objectives of this project were to: provide fundamental relationships between SOFC performance and operating conditions and transient (time dependent) transport properties; extend models to thermo-mechanical stability, thermo-chemical stability, and multilayer structures; incorporate microstructural effects such as grain boundaries and grain-size distribution; experimentally verify models and devise strategies to obtain relevant material constants; and assemble software package for integration into SECA failure analysis models.

Wachsman, E.D.; Duncan, K.L.; Ebrahimi, F.

2005-01-27T23:59:59.000Z

227

Multiparameter Moment Matching Model Reduction Approach for Generating Geometrically Parameterized Interconnect Performance Models  

E-Print Network [OSTI]

In this paper we describe an approach for generating geometrically-parameterized integrated-circuit interconnect models that are efficient enough for use in interconnect synthesis. The model generation approach presented ...

Daniel, Luca

228

Resonant Oscillations and Tidal Heating in Coalescing Binary Neutron Stars  

E-Print Network [OSTI]

Tidal interaction in a coalescing neutron star binary can resonantly excite the g-mode oscillations of the neutron star when the frequency of the tidal driving force equals the intrinsic g-mode frequencies. We study the g-mode oscillations of cold neutron stars using recent microscopic nuclear equations of state, where we determine self-consistently the sound speed and Brunt-V\\"ais\\"al\\"a frequency in the nuclear liquid core. The properties of the g-modes associated with the stable stratification of the core depend sensitively on the pressure-density relation as well as the symmetry energy of the dense nuclear matter. The frequencies of the first ten g-modes lie approximately in the range of $10-100$ Hz. Resonant excitations of these g-modes during the last few minutes of the binary coalescence result in energy transfer and angular momentum transfer from the binary orbit to the neutron star. The angular momentum transfer is possible because a dynamical tidal lag develops even in the absence of fluid viscosity. However, since the coupling between the g-mode and the tidal potential is rather weak, the amount of energy transfer during a resonance and the induced orbital phase error are very small. Resonant excitations of the g-modes play an important role in tidal heating of binary neutron stars. Without the resonances, viscous dissipation is effective only when the stars are close to contact. The resonant oscillations result in dissipation at much larger orbital separation. The actual amount of tidal heating depends on the viscosity of the neutron star. Using the microscopic viscosity, we find that the binary neutron stars are heated to a temperature $\\sim 10^8$ K before they come into contact.

Dong Lai

1994-04-25T23:59:59.000Z

229

Assessing the performance of thermospheric modelling with data assimilation throughout solar cycles 23 and 24  

E-Print Network [OSTI]

Data assimilation procedures have been developed for thermospheric models using satellite density measurements as part of the EU Framework Package 7 ATMOP Project. Two models were studied; one a general circulation model, TIEGCM, and the other a semi-empirical drag temperature model, DTM. Results of runs using data assimilation with these models were compared with independent density observations from CHAMP and GRACE satellites throughout solar cycles 23 and 24. Time periods of 60 days were examined at solar minimum and maximum, including the 2003 Hallowe'en storms. The differences between the physical and the semi-empirical models have been characterised. Results indicate that both models tend to show similar behaviour; underestimating densities at solar maximum, and overestimating them at solar minimum. DTM performed better at solar minimum, with both models less accurate at solar maximum. A mean improvement of ~4% was found using data assimilation with TIEGCM. With further improvements, the use of general ...

Murray, Sophie A; Jackson, David R; Bruinsma, Sean L

2015-01-01T23:59:59.000Z

230

Advanced modeling and simulation to design and manufacture high performance and reliable advanced microelectronics and microsystems.  

SciTech Connect (OSTI)

An interdisciplinary team of scientists and engineers having broad expertise in materials processing and properties, materials characterization, and computational mechanics was assembled to develop science-based modeling/simulation technology to design and reproducibly manufacture high performance and reliable, complex microelectronics and microsystems. The team's efforts focused on defining and developing a science-based infrastructure to enable predictive compaction, sintering, stress, and thermomechanical modeling in ''real systems'', including: (1) developing techniques to and determining materials properties and constitutive behavior required for modeling; (2) developing new, improved/updated models and modeling capabilities, (3) ensuring that models are representative of the physical phenomena being simulated; and (4) assessing existing modeling capabilities to identify advances necessary to facilitate the practical application of Sandia's predictive modeling technology.

Nettleship, Ian (University of Pittsburgh, Pittsburgh, PA); Hinklin, Thomas; Holcomb, David Joseph; Tandon, Rajan; Arguello, Jose Guadalupe, Jr. (,; .); Dempsey, James Franklin; Ewsuk, Kevin Gregory; Neilsen, Michael K.; Lanagan, Michael (Pennsylvania State University, University Park, PA)

2007-07-01T23:59:59.000Z

231

Development of a Model Specification for Performance MonitoringSystems for Commercial Buildings  

SciTech Connect (OSTI)

The paper describes the development of a model specification for performance monitoring systems for commercial buildings. The specification focuses on four key aspects of performance monitoring: (1) performance metrics; (2) measurement system requirements; (3) data acquisition and archiving; and (4) data visualization and reporting. The aim is to assist building owners in specifying the extensions to their control systems that are required to provide building operators with the information needed to operate their buildings more efficiently and to provide automated diagnostic tools with the information required to detect and diagnose faults and problems that degrade energy performance. The paper reviews the potential benefits of performance monitoring, describes the specification guide and discusses briefly the ways in which it could be implemented. A prototype advanced visualization tool is also described, along with its application to performance monitoring. The paper concludes with a description of the ways in which the specification and the visualization tool are being disseminated and deployed.

Haves, Philip; Hitchcock, Robert J.; Gillespie, Kenneth L.; Brook, Martha; Shockman, Christine; Deringer, Joseph J.; Kinney,Kristopher L.

2006-08-01T23:59:59.000Z

232

A Conceptual Restoration Plan and Tidal Hydrology Assessment for Reconnecting Spring Branch Creek to Suisun Marsh, Solano County, California  

E-Print Network [OSTI]

Marsh. UC Berkeley LA 222 Hydrology Term Paper. Orr, M. , S.Restoration Plan and Tidal Hydrology Assessment forthree consists of a tidal hydrology analysis before and

Olson, Jessica J.

2012-01-01T23:59:59.000Z

233

Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean Current, and In-Stream Hydrokinetic Power Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean Current,...

234

MHK Projects/Cohansey River Tidal Energy | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 Tidal <CETOCohansey River Tidal

235

SCRAM: a fast computational model for the optical performance of point fucus solar central receiver systems  

SciTech Connect (OSTI)

Because of the complexities of heliostat shadowing and blocking calculations, computational models for the optical performance of point focus central receiver (PFCR) systems tend to be too slow for many important applications, such as optimization studies based on performance with realistic weather data. In this paper, a mathematical approximation procedure, designated Sandia Central Receiver Approximation Model (SCRAM) will be described. Rather than simulating the system components from first principles, it relies on data generated by the DELSOL code of Dellin and Fish for the optical performance of PFCR systems, and abstracts a mathematical model using a stepwise regression procedure. The result is a computational procedure which allows the user to define the heliostat field boundaries and tower height arbitrarily, generating a model for optical field performance, including shadowing, blocking, cosine, losses, and atmospheric attenuation, and which requires only a polynomial evaluation for each set of sun angles. A comparison with DELSOL for three different fields on three representative days indicates that the rms error of the approximation is 1-3% and that the new code is 1,000-3,000 times as fast as DELSOL. It is also shown that one reason that the accuracy in field performance predictions is higher than that of the generting function for the model is that much of the error in the generating function is due to an oscillatory behavior associated with a moire pattern in the optical response of the heiostat field.

Bergeron, K. D.; Chiang, C. J.

1980-04-01T23:59:59.000Z

236

Peer review presentation on systems performance modeling and solar advisor support.  

SciTech Connect (OSTI)

Accurate Performance Models are Critical to Project Development and Technology Evaluation - Accuracy and Uncertainty of Commonly-Used Models Unknown and Models Disagree. A Model Evaluation Process Has Been Developed with Industry, and High-Quality Weather and System Performance Data Sets Have Been Collected: (1) Evaluation is Underway using Residual Analysis of Hourly and Sub-Hourly Data for Clear and Diffuse Climates to Evaluate and Improve Models; and (2) Initial Results Have Been or Will Soon Be Presented at Key Conferences. Evaluation of Widely-Used Module, Inverter, and Irradiance Models, Including Those in SAM, PVWatts, and PVSyst, Will Be Completed This Year. Stochastic Modeling Has Been Performed to Support Reliability Task and Will Add Value to Parametric Analysis. An Industry Workshop will be Held This Fall To Review Results, Set Priorities. Support and Analysis has been Provided for TPP's, SETP, and PV Community. Goals for Future Work Include: (1) Improving Understanding of and Validating System Derate Factors; and (2) Developing a Dynamic Electrical Model of Arrays with Shaded or Mismatched Modules to Support Transient Analysis of Large Fields.

Cameron, Christopher P.

2010-05-01T23:59:59.000Z

237

TIDAL HEATING OF EXTRASOLAR PLANETS Brian Jackson, Richard Greenberg, and Rory Barnes  

E-Print Network [OSTI]

TIDAL HEATING OF EXTRASOLAR PLANETS Brian Jackson, Richard Greenberg, and Rory Barnes Lunar and gas cleared away, and as the orbits evolved there was substantial tidal heating within the planets. The tidal heating history of each planet may have contributed significantly to the thermal budget governing

Barnes, Rory

238

Resource Sharing in QPN-based Performance Models Charles University Prague, Faculty of Mathematics and Physics, Prague, Czech Republic.  

E-Print Network [OSTI]

Resource Sharing in QPN-based Performance Models V. Babka Charles University Prague, Faculty needed to solve the model can be significantly influenced by resource sharing, capturing this influence separate resource and performance models and proposes a method of integrating these models at the tool

239

Model-based performance monitoring: Review of diagnostic methods and chiller case study  

SciTech Connect (OSTI)

The paper commences by reviewing the variety of technical approaches to the problem of detecting and diagnosing faulty operation in order to improve the actual performance of buildings. The review covers manual and automated methods, active testing and passive monitoring, the different classes of models used in fault detection, and methods of diagnosis. The process of model-based fault detection is then illustrated by describing the use of relatively simple empirical models of chiller energy performance to monitor equipment degradation and control problems. The CoolTools(trademark) chiller model identification package is used to fit the DOE-2 chiller model to on-site measurements from a building instrumented with high quality sensors. The need for simple algorithms to reject transient data, detect power surges and identify control problems is discussed, as is the use of energy balance checks to detect sensor problems. The accuracy with which the chiller model can be expected! to predict performance is assessed from the goodness of fit obtained and the implications for fault detection sensitivity and sensor accuracy requirements are discussed. A case study is described in which the model was applied retroactively to high-quality data collected in a San Francisco office building as part of a related project (Piette et al. 1999).

Haves, Phil; Khalsa, Sat Kartar

2000-05-01T23:59:59.000Z

240

Empirical Performance Model-Driven Data Layout Optimization and Library Call Selection for Tensor Contraction Expressions  

SciTech Connect (OSTI)

Empirical optimizers like ATLAS have been very effective in optimizing computational kernels in libraries. The best choice of parameters such as tile size and degree of loop unrolling is determined by executing different versions of the computation. In contrast, optimizing compilers use a model-driven approach to program transformation. While the model-driven approach of optimizing compilers is generally orders of magnitude faster than ATLAS-like library generators, its effectiveness can be limited by the accuracy of the performance models used. In this paper, we describe an approach where a class of computations is modeled in terms of constituent operations that are empirically measured, thereby allowing modeling of the overall execution time. The performance model with empirically determined cost components is used to perform data layout optimization together with the selection of library calls and layout transformations in the context of the Tensor Contraction Engine, a compiler for a high-level domain-specific language for expressing computational models in quantum chemistry. The effectiveness of the approach is demonstrated through experimental measurements on representative computations from quantum chemistry.

Lu, Qingda; Gao, Xiaoyang; Krishnamoorthy, Sriram; Baumgartner, Gerald; Ramanujam, J.; Sadayappan, Ponnuswamy

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC).  

SciTech Connect (OSTI)

The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. Achieving the objective of modeling the performance of a disposal scenario requires describing processes involved in waste form degradation and radionuclide release at the subcontinuum scale, beginning with mechanistic descriptions of chemical reactions and chemical kinetics at the atomic scale, and upscaling into effective, validated constitutive models for input to high-fidelity continuum scale codes for coupled multiphysics simulations of release and transport. Verification and validation (V&V) is required throughout the system to establish evidence-based metrics for the level of confidence in M&S codes and capabilities, including at the subcontiunuum scale and the constitutive models they inform or generate. This Report outlines the nature of the V&V challenge at the subcontinuum scale, an approach to incorporate V&V concepts into subcontinuum scale modeling and simulation (M&S), and a plan to incrementally incorporate effective V&V into subcontinuum scale M&S destined for use in the NEAMS Waste IPSC work flow to meet requirements of quantitative confidence in the constitutive models informed by subcontinuum scale phenomena.

Schultz, Peter Andrew

2011-12-01T23:59:59.000Z

242

REVIEW OF MECHANISTIC UNDERSTANDING AND MODELING AND UNCERTAINTY ANALYSIS METHODS FOR PREDICTING CEMENTITIOUS BARRIER PERFORMANCE  

SciTech Connect (OSTI)

Cementitious barriers for nuclear applications are one of the primary controls for preventing or limiting radionuclide release into the environment. At the present time, performance and risk assessments do not fully incorporate the effectiveness of engineered barriers because the processes that influence performance are coupled and complicated. Better understanding the behavior of cementitious barriers is necessary to evaluate and improve the design of materials and structures used for radioactive waste containment, life extension of current nuclear facilities, and design of future nuclear facilities, including those needed for nuclear fuel storage and processing, nuclear power production and waste management. The focus of the Cementitious Barriers Partnership (CBP) literature review is to document the current level of knowledge with respect to: (1) mechanisms and processes that directly influence the performance of cementitious materials (2) methodologies for modeling the performance of these mechanisms and processes and (3) approaches to addressing and quantifying uncertainties associated with performance predictions. This will serve as an important reference document for the professional community responsible for the design and performance assessment of cementitious materials in nuclear applications. This review also provides a multi-disciplinary foundation for identification, research, development and demonstration of improvements in conceptual understanding, measurements and performance modeling that would be lead to significant reductions in the uncertainties and improved confidence in the estimating the long-term performance of cementitious materials in nuclear applications. This report identifies: (1) technology gaps that may be filled by the CBP project and also (2) information and computational methods that are in currently being applied in related fields but have not yet been incorporated into performance assessments of cementitious barriers. The various chapters contain both a description of the mechanism or and a discussion of the current approaches to modeling the phenomena.

Langton, C.; Kosson, D.

2009-11-30T23:59:59.000Z

243

FRAMEWORK AND APPLICATION FOR MODELING CONTROL ROOM CREW PERFORMANCE AT NUCLEAR POWER PLANTS  

SciTech Connect (OSTI)

This paper summarizes an emerging project regarding the utilization of high-fidelity MIDAS simulations for visualizing and modeling control room crew performance at nuclear power plants. The key envisioned uses for MIDAS-based control room simulations are: (i) the estimation of human error associated with advanced control room equipment and configurations, (ii) the investigative determination of contributory cognitive factors for risk significant scenarios involving control room operating crews, and (iii) the certification of reduced staffing levels in advanced control rooms. It is proposed that MIDAS serves as a key component for the effective modeling of cognition, elements of situation awareness, and risk associated with human performance in next generation control rooms.

Ronald L Boring; David I Gertman; Tuan Q Tran; Brian F Gore

2008-09-01T23:59:59.000Z

244

Development of long-term performance models for radioactive waste forms  

SciTech Connect (OSTI)

The long-term performance of solid radioactive waste is measured by the release rate of radionuclides into the environment, which depends on corrosion or weathering rates of the solid waste form. The reactions involved depend on the characteristics of the solid matrix containing the radioactive waste, the radionuclides of interest, and their interaction with surrounding geologic materials. This chapter describes thermo-hydro-mechanical and reactive transport models related to the long-term performance of solid radioactive waste forms, including metal, ceramic, glass, steam reformer and cement. Future trends involving Monte-Carlo simulations and coupled/multi-scale process modeling are also discussed.

Bacon, Diana H.; Pierce, Eric M.

2011-03-22T23:59:59.000Z

245

LOFT as a discovery machine for jetted Tidal Disruption Events  

E-Print Network [OSTI]

This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of jetted tidal disruption events. For a summary, we refer to the paper.

Rossi, E M; Fender, R; Jonker, P; Komossa, S; Paragi, Z; Prandoni, I; Zampieri, L

2015-01-01T23:59:59.000Z

246

Heartbeat Stars and the Ringing of Tidal Pulsations Kelly Hambleton  

E-Print Network [OSTI]

Heartbeat Stars and the Ringing of Tidal Pulsations Kelly Hambleton Andrej Prsa, Don Kurtz, Jim Fuller, Susan Thompson University of Central Lancashire kmhambleton@uclan.ac.uk March 27, 2014 Kelly 3 Summary Conclusions Future Work Kelly Hambleton (UCLan) Heartbeat Stars March 27, 2014 2 / 33 #12

Â?umer, Slobodan

247

Tidal Stage Variability of Fecal Coliform and Chlorophyll a  

E-Print Network [OSTI]

leachates, leaking sewer mains, wild and do- mestic animal wastes, and runo. However, the inter- action environmental hazards, to enter an estuarine environment characterized by high variability regarding temperature to understanding both the basic ecology of tidal creeks and the applied aspects of sampling protocols and pollutant

Mallin, Michael

248

Modeling and control of network traffic for performance and secure communications  

E-Print Network [OSTI]

of Department) December 2004 Major Subject: Computer Science iii ABSTRACT Modeling and Control of Network Tra?c for Performance and Secure Communications. (December 2004) Yong Xiong, B.S., Tsinghua University (China); M.S., Chinese Academy of Space Technology..., responsive control solutions for congestion management. In this dissertation, I investigated three major topics. I proposed a generic discontin- uous congestion control model and its design methodology to guarantee asymptotic stability and eliminate tra...

Xiong, Yong

2005-02-17T23:59:59.000Z

249

Engineering Process Model for High-Temperature Electrolysis System Performance Evaluation  

SciTech Connect (OSTI)

In order to evaluate the potential hydrogen production performance of large-scale High-Temperature Electrolysis (HTE) operations, we have developed an engineering process model at INL using the commercial systems-analysis code HYSYS. Using this code, a detailed process flowsheet has been defined that includes all of the components that would be present in an actual plant such as pumps, compressors, heat exchangers, turbines, and the electrolyzer. Since the electrolyzer is not a standard HYSYS component, a custom one-dimensional electrolyzer model was developed for incorporation into the overall HYSYS process flowsheet. This electrolyzer model allows for the determination of the operating voltage, gas outlet temperatures, and electrolyzer efficiency for any specified inlet gas flow rates, current density, cell active area, and external heat loss or gain. The one-dimensional electrolyzer model was validated by comparison with results obtained from a fully 3-D computational fluid dynamics model developed using FLUENT. This report provides details on the one-dimensional electrolyzer model, the HYSYS process model for a 300 MW HTE plant, and some representative results of parametric studies performed using the HYSYS process model.

Carl M. Stoots; James E. O'Brien; Michael G. McKellar; Grant L. Hawkes

2005-11-01T23:59:59.000Z

250

Waste package performance assessment: Deterministic system model, program scope and specification  

SciTech Connect (OSTI)

Integrated assessments of the performance of nuclear waste package designs must be made in order to qualify waste package designs with respect to containment time and release-rate requirements. PANDORA is a computer-based model of the waste package and of the processes affecting it over the long terms, specific to conditions at the proposed Yucca Mountain, Nevada, site. The processes PANDORA models include: changes in inventories due to radioactive decay, gamma radiation dose rate in and near the package, heat transfer, mechanical behavior, groundwater contact, corrosion, waste form alteration, and radionuclide release. The model tracks the development and coupling of these processes over time. The process models are simplified ones that focus on major effects and on coupling. This report documents our conceptual model development and provides a specification for the computer program. The current model is the first in a series. Succeeding models will use guidance from results of preceding models in the PANDORA series and will incorporate results of recently completed experiments and calculations on processes affecting performance. 22 refs., 21 figs., 9 tabs.

O`Connell, W.J.; Drach, R.S.

1986-10-02T23:59:59.000Z

251

Modeling the Performance and the Energy Usage of Wireless Sensor Networks by Retrial Queueing Systems  

E-Print Network [OSTI]

Modeling the Performance and the Energy Usage of Wireless Sensor Networks by Retrial Queueing and the energy usage of the sensor network. Two operations are compared. In the first case only the event driven requests can initiate reaching the radio trans- mission (RF) unit. Time driven requests have to wait

Sztrik, János

252

A Model-Based Impedance Control Scheme for High-Performance Hydraulic Joints  

E-Print Network [OSTI]

A Model-Based Impedance Control Scheme for High-Performance Hydraulic Joints Glen Bilodeau1, Greece Abstract Impedance control of a hydraulic servoactuator joint system is discussed in this paper individually. Due to nonlinear properties of hydraulic actuators, impedance control is difficult. The control

Papadopoulos, Evangelos

253

Computational Modeling of Rotor Blade Performance Degradation Due to Ice Accretion  

E-Print Network [OSTI]

PENNSTATE _ Computational Modeling of Rotor Blade Performance Degradation Due to Ice Accretion, 2013 9:00 a.m. 301 Steidle Building Ice accretion on helicopter rotor blades can cause significant. If unabated, rotor ice can accumulate to the point where the vehicle can no longer maintain flight

Maroncelli, Mark

254

Quantifying Performance Benefits of Overlap using MPI-2 in a Seismic Modeling Application  

E-Print Network [OSTI]

motion simulation code based on a parallel finite difference solution of the 3-D velocity- stress waveQuantifying Performance Benefits of Overlap using MPI-2 in a Seismic Modeling Application Sreeram and Engineering 2 Ohio Supercomputer Center The Ohio State University Columbus, OH, USA 43212 Columbus, OH, USA

Panda, Dhabaleswar K.

255

On a test of the modified BCS theory performance in the picket fence model  

E-Print Network [OSTI]

The errors in the arguments, numerical results, and conclusions in the paper "Test of a modified BCS theory performance in the picket fence model" [Nucl. Phys. A 822 (2009) 1] by V.Yu. Ponomarev and A.I. Vdovin are pointed out. Its repetitions of already published material are also discussed.

Nguyen Dinh Dang

2009-04-03T23:59:59.000Z

256

Propagating Uncertainty in Solar Panel Performance for Life Cycle Modeling in Early Stage Design  

E-Print Network [OSTI]

Propagating Uncertainty in Solar Panel Performance for Life Cycle Modeling in Early Stage Design. This work is conducted in the context of an amorphous photovoltaic (PV) panel, using data gathered from the National Solar Radiation Database, as well as realistic data collected from an experimental hardware setup

Yang, Maria

257

Performance modeling and cell design for high concentration methanol fuel cells  

E-Print Network [OSTI]

) it reduces the fuel efficiency (methanol is reacted without producing electrical current). We canChapter 50 Performance modeling and cell design for high concentration methanol fuel cells C. E The direct methanol fuel cell (DMFC) has become a lead- ing contender to replace the lithium-ion (Li

258

1 MODELING THE PERFORMANCE OF ULTRAVIOLET REACTOR IN EULERIAN AND LAGRANGIAN FRAMEWORKS  

E-Print Network [OSTI]

CFD models for simulating the performance of ultraviolet (UV) reactors for micro-organism inactivation were developed in Eulerian and Lagrangian frameworks, taking into account hydrodynamics, kinetics, and radiation field within UV reactor. In the Lagrangian framework, micro-organisms were treated as discrete particles where the trajectory was predicted by integrating the force balance on the particle. In the Eulerian framework, the conservation equation of species (microorganisms) was solved along with the transport equations. The fluid flow was characterized experimentally using particle image velocimetry (PIV) flow visualization techniques and modeled using CFD for a UV reactor prototype model. The performance of annular UV reactors with an inlet parallel and perpendicular to the reactor axis were investigated. The results indicated that the fluid flow distribution within the reactor volume can significantly affect the reactor performance. Both the Eulerian and Lagrangian models were used to obtain complimentary information on the reactors; while the Lagrangian method provided an estimation of the UV-fluence distribution and the trajectory of species, the Eulerian approach showed the concentration distribution and local photo-reaction rates. The combined information can be used to predict and monitor reactor performance and to improve the reactor design.

Angelo Sozzi; Fariborz Taghipour

2006-01-01T23:59:59.000Z

259

Modeling the Performance, Emissions, and Cost of an Entrained-Flow Gasification Combined Cycle System Using  

E-Print Network [OSTI]

1 Modeling the Performance, Emissions, and Cost of an Entrained-Flow Gasification Combined Cycle Carolina State University ABSTRACT Gasification is a globally emerging technology in commercial markets for the conversion of a variety of feedstocks, including coal, heavy residue oil, biomass, solid waste, and others

Frey, H. Christopher

260

ASES Proc. Solar 2010, Phoenix, AZ HIGH PERFORMANCE MSG SATELLITE MODEL FOR OPERATIONAL  

E-Print Network [OSTI]

terrain affects exploitation of solar energy. In this article we present innovative features of MSG area of interest, which extends from North Europe to North Africa. The satellite data calibration© ASES ­ Proc. Solar 2010, Phoenix, AZ HIGH PERFORMANCE MSG SATELLITE MODEL FOR OPERATIONAL SOLAR

Perez, Richard R.

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

A data-based approach for multivariate model predictive control performance monitoring$  

E-Print Network [OSTI]

of the proposed methodology is demonstrated in a case study of the Wood­Berry distillation column system. & 2010 model predictive control (MPC) controller, which systematically integrates both the assessment'' user-predefined one, this method can properly evaluate the performance of an MPC controller

Chen, Sheng

262

TIDAL TAIL EJECTION AS A SIGNATURE OF TYPE Ia SUPERNOVAE FROM WHITE DWARF MERGERS  

SciTech Connect (OSTI)

The merger of two white dwarfs may be preceded by the ejection of some mass in ''tidal tails,'' creating a circumstellar medium around the system. We consider the variety of observational signatures from this material, which depend on the lag time between the start of the merger and the ultimate explosion (assuming one occurs) of the system in a Type Ia supernova (SN Ia). If the time lag is fairly short, then the interaction of the supernova ejecta with the tails could lead to detectable shock emission at radio, optical, and/or X-ray wavelengths. At somewhat later times, the tails produce relatively broad NaID absorption lines with velocity widths of the order of the white dwarf escape speed ({approx}1000 km s{sup -1}). That none of these signatures have been detected in normal SNe Ia constrains the lag time to be either very short ({approx}< 100 s) or fairly long ({approx}> 100 yr). If the tails have expanded and cooled over timescales {approx}10{sup 4} yr, then they could be observable through narrow NaID and Ca II H and K absorption lines in the spectra, which are seen in some fraction of SNe Ia. Using a combination of three-dimensional and one-dimensional hydrodynamical codes, we model the mass loss from tidal interactions in binary systems, and the subsequent interactions with the interstellar medium, which produce a slow-moving, dense shell of gas. We synthesize NaID line profiles by ray casting through this shell, and show that in some circumstances tidal tails could be responsible for narrow absorptions similar to those observed.

Raskin, Cody; Kasen, Daniel [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

2013-07-20T23:59:59.000Z

263

Towards an Abstraction-Friendly Programming Model for High Productivity and High Performance Computing  

SciTech Connect (OSTI)

General purpose languages, such as C++, permit the construction of various high level abstractions to hide redundant, low level details and accelerate programming productivity. Example abstractions include functions, data structures, classes, templates and so on. However, the use of abstractions significantly impedes static code analyses and optimizations, including parallelization, applied to the abstractions complex implementations. As a result, there is a common perception that performance is inversely proportional to the level of abstraction. On the other hand, programming large scale, possibly heterogeneous high-performance computing systems is notoriously difficult and programmers are less likely to abandon the help from high level abstractions when solving real-world, complex problems. Therefore, the need for programming models balancing both programming productivity and execution performance has reached a new level of criticality. We are exploring a novel abstraction-friendly programming model in order to support high productivity and high performance computing. We believe that standard or domain-specific semantics associated with high level abstractions can be exploited to aid compiler analyses and optimizations, thus helping achieving high performance without losing high productivity. We encode representative abstractions and their useful semantics into an abstraction specification file. In the meantime, an accessible, source-to-source compiler infrastructure (the ROSE compiler) is used to facilitate recognizing high level abstractions and utilizing their semantics for more optimization opportunities. Our initial work has shown that recognizing abstractions and knowing their semantics within a compiler can dramatically extend the applicability of existing optimizations, including automatic parallelization. Moreover, a new set of optimizations have become possible within an abstraction-friendly and semantics-aware programming model. In the future, we will apply our programming model to more large scale applications. In particular, we plan to classify and formalize more high level abstractions and semantics which are relevant to high performance computing. We will also investigate better ways to allow language designers, library developers and programmers to communicate abstraction and semantics information with each other.

Liao, C; Quinlan, D; Panas, T

2009-10-06T23:59:59.000Z

264

ULTRAVIOLET/OPTICAL/INFRARED COLOR SEQUENCES ALONG THE TIDAL RING/ARM OF Arp 107  

SciTech Connect (OSTI)

We construct UV/optical/IR spectral energy distributions for 29 star forming regions in the interacting galaxy Arp 107, using GALEX UV, Sloan Digitized Sky Survey optical, and Spitzer infrared images. In an earlier study utilizing only the Spitzer data, we found a sequence in the mid-infrared colors of star-forming knots along the strong tidal arm in this system. In the current study, we find sequences in the UV/optical colors along the tidal arm that mirror those in the mid-infrared, with blue UV/optical colors found for regions that are red in the mid-infrared, and vice versa. With single-burst stellar population synthesis models, we find a sequence in the average stellar age along this arm, with younger stars preferentially located further out in the arm. Models that allow two populations of different ages and dust attenuations suggest that there may be both a young component and an older population present in these regions. Thus the observed color sequences may be better interpreted as a sequence in the relative proportion of young and old stars along the arm, with a larger fraction of young stars near the end. Comparison with star forming regions in other interacting galaxies shows that the Arp 107 regions are relatively quiescent, with less intense star formation than in many other systems.

Lapham, Ryen C.; Smith, Beverly J. [Department of Physics and Astronomy, East Tennessee State University, Johnson City, TN 37614 (United States); Struck, Curtis, E-mail: rlapham@nmt.edu, E-mail: smithbj@etsu.edu, E-mail: curt@iastate.edu [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States)

2013-05-15T23:59:59.000Z

265

SUMO, System performance assessment for a high-level nuclear waste repository: Mathematical models  

SciTech Connect (OSTI)

Following completion of the preliminary risk assessment of the potential Yucca Mountain Site by Pacific Northwest Laboratory (PNL) in 1988, the Office of Civilian Radioactive Waste Management (OCRWM) of the US Department of Energy (DOE) requested the Performance Assessment Scientific Support (PASS) Program at PNL to develop an integrated system model and computer code that provides performance and risk assessment analysis capabilities for a potential high-level nuclear waste repository. The system model that has been developed addresses the cumulative radionuclide release criteria established by the US Environmental Protection Agency (EPA) and estimates population risks in terms of dose to humans. The system model embodied in the SUMO (System Unsaturated Model) code will also allow benchmarking of other models being developed for the Yucca Mountain Project. The system model has three natural divisions: (1) source term, (2) far-field transport, and (3) dose to humans. This document gives a detailed description of the mathematics of each of these three divisions. Each of the governing equations employed is based on modeling assumptions that are widely accepted within the scientific community.

Eslinger, P.W.; Miley, T.B.; Engel, D.W.; Chamberlain, P.J. II

1992-09-01T23:59:59.000Z

266

MODEL-BASED VS. MODEL-FREE VISUAL SERVOING: A PERFORMANCE EVALUATION IN MICROSYSTEMS  

E-Print Network [OSTI]

on reconstruction of 3D model of the object and a calibrated camera to provide feedback in the cartesian space. In the second one, control values are defined in terms of image co- ordinates and no estimation of robot pose matrix, which relates the changes in the cartesian pose to the corresponding changes in the visual

Yanikoglu, Berrin

267

High Performance Computing Modeling Advances Accelerator Science for High Energy Physics  

SciTech Connect (OSTI)

The development and optimization of particle accelerators are essential for advancing our understanding of the properties of matter, energy, space and time. Particle accelerators are complex devices whose behavior involves many physical effects on multiple scales. Therefore, advanced computational tools utilizing high-performance computing (HPC) are essential for accurately modeling them. In the past decade, the DOE SciDAC program has produced such accelerator-modeling tools, which have beem employed to tackle some of the most difficult accelerator science problems. In this article we discuss the Synergia beam-dynamics framework and its applications to high-intensity particle accelerator physics. Synergia is an accelerator simulation package capable of handling the entire spectrum of beam dynamics simulations. We present the design principles, key physical and numerical models in Synergia and its performance on HPC platforms. Finally, we present the results of Synergia applications for the Fermilab proton source upgrade, known as the Proton Improvement Plan (PIP).

Amundson, James; Macridin, Alexandru; Spentzouris, Panagiotis

2014-04-29T23:59:59.000Z

268

Hyperspectral Aquatic Radiative Transfer Modeling Using a High-Performance Cluster Computing-Based Approach  

SciTech Connect (OSTI)

Abstract For aquatic studies, radiative transfer (RT) modeling can be used to compute hyperspectral above-surface remote sensing reflectance that can be utilized for inverse model development. Inverse models can provide bathymetry and inherent-and bottom-optical property estimation. Because measured oceanic field/organic datasets are often spatio-temporally sparse, synthetic data generation is useful in yielding sufficiently large datasets for inversion model development; however, these forward-modeled data are computationally expensive and time-consuming to generate. This study establishes the magnitude of wall-clock-time savings achieved for performing large, aquatic RT batch-runs using parallel computing versus a sequential approach. Given 2,600 simulations and identical compute-node characteristics, sequential architecture required ~100 hours until termination, whereas a parallel approach required only ~2.5 hours (42 compute nodes) a 40x speed-up. Tools developed for this parallel execution are discussed.

Filippi, Anthony M [ORNL; Bhaduri, Budhendra L [ORNL; Naughton, III, Thomas J [ORNL; King, Amy L [ORNL; Scott, Stephen L [ORNL; Guneralp, Inci [Texas A& M University

2012-01-01T23:59:59.000Z

269

Hyperspectral Aquatic Radiative Transfer Modeling Using a High-Performance Cluster Computing Based Approach  

SciTech Connect (OSTI)

For aquatic studies, radiative transfer (RT) modeling can be used to compute hyperspectral above-surface remote sensing reflectance that can be utilized for inverse model development. Inverse models can provide bathymetry and inherent- and bottom-optical property estimation. Because measured oceanic field/organic datasets are often spatio-temporally sparse, synthetic data generation is useful in yielding sufficiently large datasets for inversion model development; however, these forward-modeled data are computationally expensive and time-consuming to generate. This study establishes the magnitude of wall-clock-time savings achieved for performing large, aquatic RT batch-runs using parallel computing versus a sequential approach. Given 2,600 simulations and identical compute-node characteristics, sequential architecture required {approx}100 hours until termination, whereas a parallel approach required only {approx}2.5 hours (42 compute nodes) - a 40x speed-up. Tools developed for this parallel execution are discussed.

Fillippi, Anthony [Texas A& M University; Bhaduri, Budhendra L [ORNL; Naughton, III, Thomas J [ORNL; King, Amy L [ORNL; Scott, Stephen L [ORNL; Guneralp, Inci [Texas A& M University

2012-01-01T23:59:59.000Z

270

A Service Oriented Architecture for Exploring High Performance Distributed Power Models  

SciTech Connect (OSTI)

Power grids are increasingly incorporating high quality, high throughput sensor devices inside power distribution networks. These devices are driving an unprecedented increase in the volume and rate of available information. The real-time requirements for handling this data are beyond the capacity of conventional power models running in central utilities. Hence, we are exploring distributed power models deployed at the regional scale. The connection of these models for a larger geographic region is supported by a distributed system architecture. This architecture is built in a service oriented style, whereby distributed power models running on high performance clusters are exposed as services. Each service is semantically annotated and therefore can be discovered through a service catalog and composed into workflows. The overall architecture has been implemented as an integrated workflow environment useful for power researchers to explore newly developed distributed power models.

Liu, Yan; Chase, Jared M.; Gorton, Ian

2012-11-12T23:59:59.000Z

271

Conformally curved binary black hole initial data including tidal deformations and outgoing radiation  

E-Print Network [OSTI]

(Abridged) By asymptotically matching a post-Newtonian (PN) metric to two tidally perturbed Schwarzschild metrics, we generate approximate initial data (in the form of a 4-metric) for a nonspinning black hole binary in a circular orbit. We carry out this matching through O(v^4) in the binary's orbital velocity v, so the resulting data are conformally curved. Far from the holes, we use the appropriate PN metric that accounts for retardation, which we construct using the highest-order PN expressions available to compute the binary's past history. The data set's uncontrolled remainders are thus O(v^5) throughout the timeslice; we also generate an extension to the data set that has uncontrolled remainders of O(v^6) in the purely PN portion of the timeslice (i.e., not too close to the holes). The resulting data are smooth, since we join all the metrics together by smoothly interpolating between them. We perform this interpolation using transition functions constructed to avoid introducing excessive additional constraint violations. Due to their inclusion of tidal deformations and outgoing radiation, these data should substantially reduce the initial spurious ("junk") radiation observed in current simulations that use conformally flat initial data. Such reductions in the nonphysical components of the initial data will be necessary for simulations to achieve the accuracy required to supply Advanced LIGO and LISA with the templates necessary for parameter estimation.

Nathan K. Johnson-McDaniel; Nicolas Yunes; Wolfgang Tichy; Benjamin J. Owen

2009-07-06T23:59:59.000Z

272

Numeric-modeling sensitivity analysis of the performance of wind turbine arrays  

SciTech Connect (OSTI)

An evaluation of the numerical model created by Lissaman for predicting the performance of wind turbine arrays has been made. Model predictions of the wake parameters have been compared with both full-scale and wind tunnel measurements. Only limited, full-scale data were available, while wind tunnel studies showed difficulties in representing real meteorological conditions. Nevertheless, several modifications and additions have been made to the model using both theoretical and empirical techniques and the new model shows good correlation with experiment. The larger wake growth rate and shorter near wake length predicted by the new model lead to reduced interference effects on downstream turbines and hence greater array efficiencies. The array model has also been re-examined and now incorporates the ability to show the effects of real meteorological conditions such as variations in wind speed and unsteady winds. The resulting computer code has been run to show the sensitivity of array performance to meteorological, machine, and array parameters. Ambient turbulence and windwise spacing are shown to dominate, while hub height ratio is seen to be relatively unimportant. Finally, a detailed analysis of the Goodnoe Hills wind farm in Washington has been made to show how power output can be expected to vary with ambient turbulence, wind speed, and wind direction.

Lissaman, P.B.S.; Gyatt, G.W.; Zalay, A.D.

1982-06-01T23:59:59.000Z

273

Seasonal versus Episodic Performance Evaluation for an Eulerian Photochemical Air Quality Model  

SciTech Connect (OSTI)

This study presents detailed evaluation of the seasonal and episodic performance of the Community Multiscale Air Quality (CMAQ) modeling system applied to simulate air quality at a fine grid spacing (4 km horizontal resolution) in central California, where ozone air pollution problems are severe. A rich aerometric database collected during the summer 2000 Central California Ozone Study (CCOS) is used to prepare model inputs and to evaluate meteorological simulations and chemical outputs. We examine both temporal and spatial behaviors of ozone predictions. We highlight synoptically driven high-ozone events (exemplified by the four intensive operating periods (IOPs)) for evaluating both meteorological inputs and chemical outputs (ozone and its precursors) and compare them to the summer average. For most of the summer days, cross-domain normalized gross errors are less than 25% for modeled hourly ozone, and normalized biases are between {+-}15% for both hourly and peak (1 h and 8 h) ozone. The domain-wide aggregated metrics indicate similar performance between the IOPs and the whole summer with respect to predicted ozone and its precursors. Episode-to-episode differences in ozone predictions are more pronounced at a subregional level. The model performs consistently better in the San Joaquin Valley than other air basins, and episodic ozone predictions there are similar to the summer average. Poorer model performance (normalized peak ozone biases <-15% or >15%) is found in the Sacramento Valley and the Bay Area and is most noticeable in episodes that are subject to the largest uncertainties in meteorological fields (wind directions in the Sacramento Valley and timing and strength of onshore flow in the Bay Area) within the boundary layer.

Jin, Ling; Brown, Nancy J.; Harley, Robert A.; Bao, Jian-Wen; Michelson, Sara A; Wilczak, James M

2010-04-16T23:59:59.000Z

274

Evaluation of Model Results and Measured Performance of Net-Zero Energy Homes in Hawaii: Preprint  

SciTech Connect (OSTI)

The Kaupuni community consists of 19 affordable net-zero energy homes that were built within the Waianae Valley of Oahu, Hawaii in 2011. The project was developed for the native Hawaiian community led by the Department of Hawaiian Homelands. This paper presents a comparison of the modeled and measured energy performance of the homes. Over the first year of occupancy, the community as a whole performed within 1% of the net-zero energy goals. The data show a range of performance from house to house with the majority of the homes consistently near or exceeding net-zero, while a few fall short of the predicted net-zero energy performance. The impact of building floor plan, weather, and cooling set point on this comparison is discussed. The project demonstrates the value of using building energy simulations as a tool to assist the project to achieve energy performance goals. Lessons learned from the energy performance monitoring has had immediate benefits in providing feedback to the homeowners, and will be used to influence future energy efficient designs in Hawaii and other tropical climates.

Norton, P.; Kiatreungwattana, K.; Kelly, K. J.

2013-03-01T23:59:59.000Z

275

Broadband Model Performance for an Updated National Solar Radiation Database in the United States of America: Preprint  

SciTech Connect (OSTI)

Updated review of broadband model performance in a project being done to update the existing United States National Solar Radiation Database (NSRDB).

Myers, D. R.; Wilcox, S.; Marion, W.; George, R.; Anderberg, M.

2005-09-01T23:59:59.000Z

276

Revealing the escape mechanism of three-dimensional orbits in a tidally limited star cluster  

E-Print Network [OSTI]

The aim of this work is to explore the escape process of three-dimensional orbits in a star cluster rotating around its parent galaxy in a circular orbit. The gravitational field of the cluster is represented by a smooth, spherically symmetric Plummer potential, while the tidal approximation was used to model the steady tidal field of the galaxy. We conduct a thorough numerical analysis distinguishing between regular and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels. It is of particular interest to locate the escape basins towards the two exit channels and relate them with the corresponding escape times of the orbits. For this purpose, we split our investigation into three cases depending on the initial value of the $z$ coordinate which was used for launching the stars. The most noticeable finding is that the majority of stars initiated very close to the primary $(x,y)$ plane move in chaotic orbits and they remain trapped for vast time intervals, while orbits with relatively high values of $z_0$ on the other hand, form well-defined basins of escape. It was also observed, that for energy levels close to the critical escape energy the escape rates of orbits are large, while for much higher values of energy most of the orbits have low escape periods or they escape immediately to infinity. We hope our outcomes to be useful for a further understanding of the dissolution process and the escape mechanism in open star clusters.

Euaggelos E. Zotos

2014-11-18T23:59:59.000Z

277

Multiple-Zone Variable Refrigerant Flow System Modeling and Equipment Performance Mapping  

SciTech Connect (OSTI)

We developed a variable refrigerant flow (VRF) vapor compression system model, which has five indoor units, one outdoor unit and one water heater. The VRF system can run simultaneous space conditioning (cooling or heating) and water heating. The indoor units and outdoor unit use fin-&-tube coil heat exchangers, and the water heater uses a tube-in-tube heat exchanger. The fin-&-tube coil heat exchangers are modeled using a segment-by-segment approach and the tube-in-tube water heater is modeled using a phase-by-phase approach. The compressor used is a variable-speed rotary design. We calibrated our model against a manufacturer s product literature. Based on the vapor compression system model, we investigated the methodology for generating VRF equipment performance maps, which can be used for energy simulations in TRNSYS and EnergyPlus, etc. In the study, the major independent variables for mapping are identified and the deviations between the simplified performance map and the actual equipment system simulation are quantified.

Shen, Bo [ORNL] [ORNL; Rice, C Keith [ORNL] [ORNL

2012-01-01T23:59:59.000Z

278

Fuel Performance Experiments and Modeling: Fission Gas Bubble Nucleation and Growth in Alloy Nuclear Fuels  

SciTech Connect (OSTI)

Advanced fast reactor systems being developed under the DOE's Advanced Fuel Cycle Initiative are designed to destroy TRU isotopes generated in existing and future nuclear energy systems. Over the past 40 years, multiple experiments and demonstrations have been completed using U-Zr, U-Pu-Zr, U-Mo and other metal alloys. As a result, multiple empirical and semi-empirical relationships have been established to develop empirical performance modeling codes. many mechamistic questions about fission as mobility, bubble coalescience, and gas release have been answered through industrial experience, reearch, and empirical understanding. The advent of modern computational materials science, however, opens new doors of development such that physics-based multi-scale models may be developed to enable a new generation of predictive fuel performance codes that are not limited by empiricism.

McDeavitt, Sean; Shao, Lin; Tsvetkov, Pavel; Wirth, Brian; Kennedy, Rory

2014-04-07T23:59:59.000Z

279

Investigation of tidal power, Cobscook Bay, Maine. Environmental Appendix  

SciTech Connect (OSTI)

This report presents information regarding existing terrestrial and marine resources and water quality conditions in the Cobscook Bay area. A preliminary assessment of impacts from a tidal power project is also presented and data gaps are identified. Reports contained in the appendix were prepared by the U.S. Fish and Wildlife Service, the National Marine Fisheries Service, the University of Maine at Orino, School of Forestry Resources and the U.S. Army Corps of Engineers.

Not Available

1980-08-01T23:59:59.000Z

280

Extremely Close-In Giant Planets from Tidal Capture  

E-Print Network [OSTI]

Planets that form around stars born in dense stellar environments are subject to dynamical perturbations from other stars in the system. These perturbations will strip outer planets, forming a population of free-floating planets, some of which will be tidally captured before they evaporate from the system. For systems with velocity dispersion of 1 km/s, Jupiter-mass planets can be captured into orbits with periods of 0.1-0.4 days, which are generally stable over a Gyr, assuming quadratic suppression of eddy viscosity in the convective zones of the host stars. Under this assumption, and that most stars form several massive planets at separations 5-50 AU, about 0.03% of stars in rich, mature open clusters should have extremely close-in tidally captured planets. Approximately 0.005% of field stars should also have such planets, which may be found in field searches for transiting planets. Detection of a population of tidally-captured planets would indicate that most stars formed in stellar clusters. In globular clusters, the fraction of stars with tidally-captured planets rises to 0.1% -- in conflict with the null result of the transit search in 47 Tuc. This implies that, if the quadratic prescription for viscosity suppression is correct, planetary formation was inhibited in 47 Tuc: less than one planet of Jupiter-mass or greater (bound or free-floating) formed per cluster star. Less than half of the stars formed solar-system analogs. Brown dwarfs can also be captured in tight orbits; the lack of such companions in 47 Tuc in turn implies an upper limit on the initial frequency of brown dwarfs in this cluster. However, this upper limit is extremely sensitive to the highly uncertain timescale for orbital decay, and thus it is difficult to draw robust conclusions about the low-mass end of the mass function in 47 Tuc.

B. Scott Gaudi

2003-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

EA-1949: Admiralty Inlet Pilot Tidal Project, Puget Sound, WA  

Broader source: Energy.gov [DOE]

This EA analyzes the potential environmental effects of a proposal by the Public Utility District No. 1 of Snohomish County, Washington to construct and operate the Admiralty Inlet Tidal Project. The proposed 680-kilowatt project would be located on the east side of Admiralty Inlet in Puget Sound, Washington, about 1 kilometer west of Whidbey Island, entirely within Island County, Washington. The Federal Energy Regulatory Commission (FERC) is the lead agency. The DOE NEPA process for this project has been canceled.

282

Performance Engineering of the Community Climate System Model (PECCSM) PRINCIPAL INVESTIGATOR: Patrick H. Worley (Co-PI with  

E-Print Network [OSTI]

performance computing systems. The CCSM has evolved recently to become a first-generation Earth system model, and has been renamed the Community Earth System Model (CESM). The CESM will be used to explore new science

283

Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts.  

SciTech Connect (OSTI)

directly, rather than through simplified abstractions. It also a llows for complex representations of the source term, e.g., the explicit representation of many individual waste packages (i.e., meter - scale detail of an entire waste emplacement drift). This report fulfills the Generic Disposal System Analysis Work Packa ge Level 3 Milestone - Performance Assessment Modeling and Sensitivity Analyses of Generic Disposal System Concepts (M 3 FT - 1 4 SN08080 3 2 ).

Sevougian, S. David; Freeze, Geoffrey A. [Sandia National Laboratories, Albuquerque, NM; Gardner, William Payton [Sandia National Laboratories, Albuquerque, NM; Hammond, Glenn Edward [Sandia National Laboratories, Albuquerque, NM; Mariner, Paul [Sandia National Laboratories, Albuquerque, NM

2014-09-01T23:59:59.000Z

284

Product and Process Modeling for Functional Performance Testing in Low-Energy Building Embedded Commissioning Cases  

E-Print Network [OSTI]

PRODUCT AND PROCESS MODELING FOR FUNCTIONAL PERFORMANCE TESTING IN LOW- ENERGY BUILDING EMBEDDED COMMISSIONING CASES Omer Akin, Kwang Jun Lee, Asli Akcamete, Burcu Akinci, and James Garrett, Jr. School of Architecture and Department... south zone and north zone indoor temperature ((T south + T north ) / 2)) is below the pump set point (60 o F) or if the schedule calls for it (Gong and Claridge, 2006). We discovered that some of the wiring connecting the sensors to the control...

Akcamete, A.; Garrett, J.; Akinci, B.; Akin, O.; Lee, K. J.

2007-01-01T23:59:59.000Z

285

Resonant oscillations and tidal heating in coalescing binary neutron stars  

E-Print Network [OSTI]

Tidal interaction in a coalescing neutron star binary can resonantly excite the g-mode oscillations of the neutron star when the frequency of the tidal driving force equals the intrinsic g-mode frequencies. We study the g-mode oscillations of cold neutron stars using recent microscopic nuclear equations of state, where we determine self-consistently the sound speed and Brunt-V\\"ais\\"al\\"a frequency in the nuclear liquid core. The properties of the g-modes associated with the stable stratification of the core depend sensitively on the pressure-density relation as well as the symmetry energy of the dense nuclear matter. The frequencies of the first ten g-modes lie approximately in the range of 10-100 Hz. Resonant excitations of these g-modes during the last few minutes of the binary coalescence result in energy transfer and angular momentum transfer from the binary orbit to the neutron star. The angular momentum transfer is possible because a dynamical tidal lag develops even in the absence of fluid viscosity. ...

Lai, D

1994-01-01T23:59:59.000Z

286

Modeling and Quantification of Team Performance in Human Reliability Analysis for Probabilistic Risk Assessment  

SciTech Connect (OSTI)

Probabilistic Risk Assessment (PRA) and Human Reliability Assessment (HRA) are important technical contributors to the United States (U.S.) Nuclear Regulatory Commission’s (NRC) risk-informed and performance based approach to regulating U.S. commercial nuclear activities. Furthermore, all currently operating commercial NPPs in the U.S. are required by federal regulation to be staffed with crews of operators. Yet, aspects of team performance are underspecified in most HRA methods that are widely used in the nuclear industry. There are a variety of "emergent" team cognition and teamwork errors (e.g., communication errors) that are 1) distinct from individual human errors, and 2) important to understand from a PRA perspective. The lack of robust models or quantification of team performance is an issue that affects the accuracy and validity of HRA methods and models, leading to significant uncertainty in estimating HEPs. This paper describes research that has the objective to model and quantify team dynamics and teamwork within NPP control room crews for risk informed applications, thereby improving the technical basis of HRA, which improves the risk-informed approach the NRC uses to regulate the U.S. commercial nuclear industry.

Jeffrey C. JOe; Ronald L. Boring

2014-06-01T23:59:59.000Z

287

Climate Modeling using High-Performance Computing The Center for Applied Scientific Computing (CASC) and the LLNL Climate and Carbon  

E-Print Network [OSTI]

and NCAR in the development of a comprehensive, earth systems model. This model incorporates the most-performance climate models. Through the addition of relevant physical processes, we are developing an earth systems modeling capability as well. Our collaborators in climate research include the National Center

288

Tides and Tidal Capture in post-Main Sequence Binaries: A Period Gap for Planets Around White Dwarfs  

E-Print Network [OSTI]

The presence of a close, low-mass companion is thought to play a substantial and perhaps necessary role in shaping post-Asymptotic Giant Branch and Planetary Nebula outflows. During post-main-sequence evolution, radial expansion of the primary star, accompanied by intense winds, can significantly alter the binary orbit via tidal dissipation and mass loss. To investigate this, we couple stellar evolution models (from the zero-age main-sequence through the end of the post-main sequence) to a tidal evolution code. The binary's fate is determined by the initial masses of the primary and the companion, the initial orbit (taken to be circular), and the Reimer's mass-loss parameter. For a range of these parameters, we determine whether the orbit expands due to mass loss or decays due to tidal torques. Where a common envelope phase (CEP) ensues, we estimate the final orbital separation based on the energy required to unbind the envelope. These calculations predict a period gap for planetary companions to white dwarfs...

Nordhaus, J; Ibgui, L; Goodman, J; Burrows, A

2010-01-01T23:59:59.000Z

289

Modeling the performance and cost of lithium-ion batteries for electric-drive vehicles.  

SciTech Connect (OSTI)

This report details the Battery Performance and Cost model (BatPaC) developed at Argonne National Laboratory for lithium-ion battery packs used in automotive transportation. The model designs the battery for a specified power, energy, and type of vehicle battery. The cost of the designed battery is then calculated by accounting for every step in the lithium-ion battery manufacturing process. The assumed annual production level directly affects each process step. The total cost to the original equipment manufacturer calculated by the model includes the materials, manufacturing, and warranty costs for a battery produced in the year 2020 (in 2010 US$). At the time this report is written, this calculation is the only publically available model that performs a bottom-up lithium-ion battery design and cost calculation. Both the model and the report have been publically peer-reviewed by battery experts assembled by the U.S. Environmental Protection Agency. This report and accompanying model include changes made in response to the comments received during the peer-review. The purpose of the report is to document the equations and assumptions from which the model has been created. A user of the model will be able to recreate the calculations and perhaps more importantly, understand the driving forces for the results. Instructions for use and an illustration of model results are also presented. Almost every variable in the calculation may be changed by the user to represent a system different from the default values pre-entered into the program. The distinct advantage of using a bottom-up cost and design model is that the entire power-to-energy space may be traversed to examine the correlation between performance and cost. The BatPaC model accounts for the physical limitations of the electrochemical processes within the battery. Thus, unrealistic designs are penalized in energy density and cost, unlike cost models based on linear extrapolations. Additionally, the consequences on cost and energy density from changes in cell capacity, parallel cell groups, and manufacturing capabilities are easily assessed with the model. New proposed materials may also be examined to translate bench-scale values to the design of full-scale battery packs providing realistic energy densities and prices to the original equipment manufacturer. The model will be openly distributed to the public in the year 2011. Currently, the calculations are based in a Microsoft{reg_sign} Office Excel spreadsheet. Instructions are provided for use; however, the format is admittedly not user-friendly. A parallel development effort has created an alternate version based on a graphical user-interface that will be more intuitive to some users. The version that is more user-friendly should allow for wider adoption of the model.

Nelson, P. A.

2011-10-20T23:59:59.000Z

290

High-performance modeling acoustic and elastic waves using the parallel Dichotomy Algorithm  

SciTech Connect (OSTI)

A high-performance parallel algorithm is proposed for modeling the propagation of acoustic and elastic waves in inhomogeneous media. An initial boundary-value problem is replaced by a series of boundary-value problems for a constant elliptic operator and different right-hand sides via the integral Laguerre transform. It is proposed to solve difference equations by the conjugate gradient method for acoustic equations and by the GMRES(k) method for modeling elastic waves. A preconditioning operator was the Laplace operator that is inverted using the variable separation method. The novelty of the proposed algorithm is using the Dichotomy Algorithm , which was designed for solving a series of tridiagonal systems of linear equations, in the context of the preconditioning operator inversion. Via considering analytical solutions, it is shown that modeling wave processes for long instants of time requires high-resolution meshes. The proposed parallel fine-mesh algorithm enabled to solve real application seismic problems in acceptable time and with high accuracy. By solving model problems, it is demonstrated that the considered parallel algorithm possesses high performance and efficiency over a wide range of the number of processors (from 2 to 8192).

Fatyanov, Alexey G., E-mail: fat@nmsf.sscc.r [Institute of Computational Mathematics and Mathematical Geophysics, 630090 Novosibirsk (Russian Federation); Terekhov, Andrew V., E-mail: andrew.terekhov@mail.r [Institute of Computational Mathematics and Mathematical Geophysics, 630090 Novosibirsk (Russian Federation); Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation)

2011-03-01T23:59:59.000Z

291

Helicon thruster plasma modeling: Two-dimensional fluid-dynamics and propulsive performances  

SciTech Connect (OSTI)

An axisymmetric macroscopic model of the magnetized plasma flow inside the helicon thruster chamber is derived, assuming that the power absorbed from the helicon antenna emission is known. Ionization, confinement, subsonic flows, and production efficiency are discussed in terms of design and operation parameters. Analytical solutions and simple scaling laws for ideal plasma conditions are obtained. The chamber model is then matched with a model of the external magnetic nozzle in order to characterize the whole plasma flow and assess thruster performances. Thermal, electric, and magnetic contributions to thrust are evaluated. The energy balance provides the power conversion between ions and electrons in chamber and nozzle, and the power distribution among beam power, ionization losses, and wall losses. Thruster efficiency is assessed, and the main causes of inefficiency are identified. The thermodynamic behavior of the collisionless electron population in the nozzle is acknowledged to be poorly known and crucial for a complete plasma expansion and good thrust efficiency.

Ahedo, Eduardo; Navarro-Cavalle, Jaume [ETS Ingenieros Aeronauticos, Universidad Politecnica de Madrid, Madrid 28040 (Spain)

2013-04-15T23:59:59.000Z

292

Cpl6: The New Extensible, High-Performance Parallel Coupler forthe Community Climate System Model  

SciTech Connect (OSTI)

Coupled climate models are large, multiphysics applications designed to simulate the Earth's climate and predict the response of the climate to any changes in the forcing or boundary conditions. The Community Climate System Model (CCSM) is a widely used state-of-art climate model that has released several versions to the climate community over the past ten years. Like many climate models, CCSM employs a coupler, a functional unit that coordinates the exchange of data between parts of climate system such as the atmosphere and ocean. This paper describes the new coupler, cpl6, contained in the latest version of CCSM,CCSM3. Cpl6 introduces distributed-memory parallelism to the coupler, a class library for important coupler functions, and a standardized interface for component models. Cpl6 is implemented entirely in Fortran90 and uses Model Coupling Toolkit as the base for most of its classes. Cpl6 gives improved performance over previous versions and scales well on multiple platforms.

Craig, Anthony P.; Jacob, Robert L.; Kauffman, Brain; Bettge,Tom; Larson, Jay; Ong, Everest; Ding, Chris; He, Yun

2005-03-24T23:59:59.000Z

293

High-Performance Computer Modeling of the Cosmos-Iridium Collision  

SciTech Connect (OSTI)

This paper describes the application of a new, integrated modeling and simulation framework, encompassing the space situational awareness (SSA) enterprise, to the recent Cosmos-Iridium collision. This framework is based on a flexible, scalable architecture to enable efficient simulation of the current SSA enterprise, and to accommodate future advancements in SSA systems. In particular, the code is designed to take advantage of massively parallel, high-performance computer systems available, for example, at Lawrence Livermore National Laboratory. We will describe the application of this framework to the recent collision of the Cosmos and Iridium satellites, including (1) detailed hydrodynamic modeling of the satellite collision and resulting debris generation, (2) orbital propagation of the simulated debris and analysis of the increased risk to other satellites (3) calculation of the radar and optical signatures of the simulated debris and modeling of debris detection with space surveillance radar and optical systems (4) determination of simulated debris orbits from modeled space surveillance observations and analysis of the resulting orbital accuracy, (5) comparison of these modeling and simulation results with Space Surveillance Network observations. We will also discuss the use of this integrated modeling and simulation framework to analyze the risks and consequences of future satellite collisions and to assess strategies for mitigating or avoiding future incidents, including the addition of new sensor systems, used in conjunction with the Space Surveillance Network, for improving space situational awareness.

Olivier, S; Cook, K; Fasenfest, B; Jefferson, D; Jiang, M; Leek, J; Levatin, J; Nikolaev, S; Pertica, A; Phillion, D; Springer, K; De Vries, W

2009-08-28T23:59:59.000Z

294

Evaluation of Blade-Strike Models for Estimating the Biological Performance of Large Kaplan Hydro Turbines  

SciTech Connect (OSTI)

BioIndex testing of hydro-turbines is sought as an analog to the hydraulic index testing conducted on hydro-turbines to optimize their power production efficiency. In BioIndex testing the goal is to identify those operations within the range identified by Index testing where the survival of fish passing through the turbine is maximized. BioIndex testing includes the immediate tailrace region as well as the turbine environment between a turbine's intake trashracks and the exit of its draft tube. The US Army Corps of Engineers and the Department of Energy have been evaluating a variety of means, such as numerical and physical turbine models, to investigate the quality of flow through a hydro-turbine and other aspects of the turbine environment that determine its safety for fish. The goal is to use these tools to develop hypotheses identifying turbine operations and predictions of their biological performance that can be tested at prototype scales. Acceptance of hypotheses would be the means for validation of new operating rules for the turbine tested that would be in place when fish were passing through the turbines. The overall goal of this project is to evaluate the performance of numerical blade strike models as a tool to aid development of testable hypotheses for bioIndexing. Evaluation of the performance of numerical blade strike models is accomplished by comparing predictions of fish mortality resulting from strike by turbine runner blades with observations made using live test fish at mainstem Columbia River Dams and with other predictions of blade strike made using observations of beads passing through a 1:25 scale physical turbine model.

Deng, Zhiqun; Carlson, Thomas J.; Ploskey, Gene R.; Richmond, Marshall C.

2005-11-30T23:59:59.000Z

295

GEN-IV BENCHMARKING OF TRISO FUEL PERFORMANCE MODELS UNDER ACCIDENT CONDITIONS  

SciTech Connect (OSTI)

This document presents the benchmark plan for the calculation of particle fuel performance on safety testing experiments that are representative of operational accidental transients. The benchmark is dedicated to the modeling of fission product release under accident conditions by fuel performance codes from around the world, and the subsequent comparison to post-irradiation experiment (PIE) data from the modeled heating tests. The accident condition benchmark is divided into three parts: • The modeling of a simplified benchmark problem to assess potential numerical calculation issues at low fission product release. • The modeling of the AGR-1 and HFR-EU1bis safety testing experiments. • The comparison of the AGR-1 and HFR-EU1bis modeling results with PIE data. The simplified benchmark case, thereafter named NCC (Numerical Calculation Case), is derived from “Case 5” of the International Atomic Energy Agency (IAEA) Coordinated Research Program (CRP) on coated particle fuel technology [IAEA 2012]. It is included so participants can evaluate their codes at low fission product release. “Case 5” of the IAEA CRP-6 showed large code-to-code discrepancies in the release of fission products, which were attributed to “effects of the numerical calculation method rather than the physical model” [IAEA 2012]. The NCC is therefore intended to check if these numerical effects subsist. The first two steps imply the involvement of the benchmark participants with a modeling effort following the guidelines and recommendations provided by this document. The third step involves the collection of the modeling results by Idaho National Laboratory (INL) and the comparison of these results with the available PIE data. The objective of this document is to provide all necessary input data to model the benchmark cases, and to give some methodology guidelines and recommendations in order to make all results suitable for comparison with each other. The participants should read this document thoroughly to make sure all the data needed for their calculations is provided in the document. Missing data will be added to a revision of the document if necessary.

Blaise Collin

2014-09-01T23:59:59.000Z

296

Assessment of Strike of Adult Killer Whales by an OpenHydro Tidal Turbine Blade  

SciTech Connect (OSTI)

Report to DOE on an analysis to determine the effects of a potential impact to an endangered whale from tidal turbines proposed for deployment in Puget Sound.

Carlson, Thomas J.; Elster, Jennifer L.; Jones, Mark E.; Watson, Bruce E.; Copping, Andrea E.; Watkins, Michael L.; Jepsen, Richard A.; Metzinger, Kurt

2012-02-01T23:59:59.000Z

297

Modeling of the performance of weapons MOX fuel in light water reactors  

SciTech Connect (OSTI)

Both the Russian Federation and the US are pursing mixed uranium-plutonium oxide (MOX) fuel in light water reactors (LWRs) for the disposition of excess plutonium from disassembled nuclear warheads. Fuel performance models are used which describe the behavior of MOX fuel during irradiation under typical power reactor conditions. The objective of this project is to perform the analysis of the thermal, mechanical, and chemical behavior of weapons MOX fuel pins under LWR conditions. If fuel performance analysis indicates potential questions, it then becomes imperative to assess the fuel pin design and the proposed operating strategies to reduce the probability of clad failure and the associated release of radioactive fission products into the primary coolant system. Applying the updated code to anticipated fuel and reactor designs, which would be used for weapons MOX fuel in the US, and analyzing the performance of the WWER-100 fuel for Russian weapons plutonium disposition are addressed in this report. The COMETHE code was found to do an excellent job in predicting fuel central temperatures. Also, despite minor predicted differences in thermo-mechanical behavior of MOX and UO{sub 2} fuels, the preliminary estimate indicated that, during normal reactor operations, these deviations remained within limits foreseen by fuel pin design.

Alvis, J.; Bellanger, P.; Medvedev, P.G.; Peddicord, K.L. [Texas A and M Univ., College Station, TX (United States). Nuclear Engineering Dept.; Gellene, G.I. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemistry and Biochemistry

1999-05-01T23:59:59.000Z

298

Advanced Pellet Cladding Interaction Modeling Using the US DOE CASL Fuel Performance Code: Peregrine  

SciTech Connect (OSTI)

The US DOE’s Consortium for Advanced Simulation of LWRs (CASL) program has undertaken an effort to enhance and develop modeling and simulation tools for a virtual reactor application, including high fidelity neutronics, fluid flow/thermal hydraulics, and fuel and material behavior. The fuel performance analysis efforts aim to provide 3-dimensional capabilities for single and multiple rods to assess safety margins and the impact of plant operation and fuel rod design on the fuel thermomechanical- chemical behavior, including Pellet-Cladding Interaction (PCI) failures and CRUD-Induced Localized Corrosion (CILC) failures in PWRs. [1-3] The CASL fuel performance code, Peregrine, is an engineering scale code that is built upon the MOOSE/ELK/FOX computational FEM framework, which is also common to the fuel modeling framework, BISON [4,5]. Peregrine uses both 2-D and 3-D geometric fuel rod representations and contains a materials properties and fuel behavior model library for the UO2 and Zircaloy system common to PWR fuel derived from both open literature sources and the FALCON code [6]. The primary purpose of Peregrine is to accurately calculate the thermal, mechanical, and chemical processes active throughout a single fuel rod during operation in a reactor, for both steady state and off-normal conditions.

Jason Hales; Various

2014-06-01T23:59:59.000Z

299

Unit physics performance of a mix model in Eulerian fluid computations  

SciTech Connect (OSTI)

In this report, we evaluate the performance of a K-L drag-buoyancy mix model, described in a reference study by Dimonte-Tipton [1] hereafter denoted as [D-T]. The model was implemented in an Eulerian multi-material AMR code, and the results are discussed here for a series of unit physics tests. The tests were chosen to calibrate the model coefficients against empirical data, principally from RT (Rayleigh-Taylor) and RM (Richtmyer-Meshkov) experiments, and the present results are compared to experiments and to results reported in [D-T]. Results show the Eulerian implementation of the mix model agrees well with expectations for test problems in which there is no convective flow of the mass averaged fluid, i.e., in RT mix or in the decay of homogeneous isotropic turbulence (HIT). In RM shock-driven mix, the mix layer moves through the Eulerian computational grid, and there are differences with the previous results computed in a Lagrange frame [D-T]. The differences are attributed to the mass averaged fluid motion and examined in detail. Shock and re-shock mix are not well matched simultaneously. Results are also presented and discussed regarding model sensitivity to coefficient values and to initial conditions (IC), grid convergence, and the generation of atomically mixed volume fractions.

Vold, Erik [Los Alamos National Laboratory; Douglass, Rod [Los Alamos National Laboratory

2011-01-25T23:59:59.000Z

300

Modeling the imaging performance of prototype organic x-ray imagers  

SciTech Connect (OSTI)

A unified Monte Carlo and cascaded systems model for the simulation of active-matrix flat-panel imagers is presented. With few input parameters, the model simulated the imaging performance of previously measured flat-panel imagers with reasonable accuracy. The model is used to predict the properties of conceptual flat-panel imagers based on organic semiconductors on plastic substrates. The model suggests that significant improvements in resolution and detective quantum efficiency could be achieved by operating such a detector in a back-side illuminated configuration, or by employing two imaging arrays arranged face-to-face. The effect of semiconductor properties on the conceptual imagers is investigated. According to the model, a photodiode quantum efficiency of 25% and dark current of less than 100 pA mm{sup -2} would be satisfactory for a prototype imager, while a competitive imager would require a photodiode quantum efficiency of 40-50% with a dark current of less than 10 pA mm{sup -2} to be quantum limited over the radiographic exposure range.

Blakesley, J. C.; Speller, R. [Department of Medical Physics and Bioengineering, University College London, London WC1E 6BT, United Kingdom and Department of Physics, University of Cambridge, Cambridge CB3 OHE (United Kingdom); Department of Medical Physics and Bioengineering, University College London, London WC1E 6BT (United Kingdom)

2008-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Performance modeling of an integral, self-regulating cesium reservoir for the ATI-TFE  

SciTech Connect (OSTI)

This work covers the performance modeling of an integral metal-matrix cesium-graphite reservoir for operation in the Advanced Thermionic Initiative-Thermionic Fuel Element (ATI-TFE) converter configuration. The objectives of this task were to incorporate an intercalated cesium-graphite reservoir for the 3C[sub 24]Cs[r arrow]2C[sub 36]Cs+Cs[sub (g)] two phase equilibrium reaction into the emitter lead region of the ATI-TFE. A semi two-dimensional, cylindrical TFE computer model was used to obtain thermal and electrical converter output characteristics for various reservoir locations. The results of this study are distributions for the interelectrode voltage, output current density, and output power density as a function of axial position along the TFE emitter. This analysis was accomplished by identifying an optimum cesium pressure for three representative pins in the ATI driverless'' reactor core and determining the corresponding position of the graphite reservoir in the ATI-TFE lead region. The position for placement of the graphite reservoir was determined by performing a first-order heat transfer analysis of the TFE lead region to determine its temperature distribution. The results of this analysis indicate that for the graphite reservoirs investigated the 3C[sub 24]Cs[r arrow]2C[sub 36]Cs+Cs[sub (g)] equilibrium reaction reservoir is ideal for placement in the TFE emitter lead region. This reservoir can be directly coupled to the emitter, through conduction, to provide the desired cesium pressure for optimum performance. The cesium pressure corresponding to the optimum converter output performance was found to be 2.18 torr for the ATI core least power TFE, 2.92 torr for the average power TFE, and 4.93 torr for the maximum power TFE.

Thayer, K.L.; Ramalingam, M.L. (UES, In., 4401 Dayton-Xenia Road, Dayton, Ohio 45432-1894 (United States)); Young, T.J. (Aerospace Power Division, Wright Laboratory/POOC, Wright-Patterson AFB, Ohio 45433-6563 (United States))

1993-01-20T23:59:59.000Z

302

Foundation Heat Exchanger Final Report: Demonstration, Measured Performance, and Validated Model and Design Tool  

SciTech Connect (OSTI)

Geothermal heat pumps, sometimes called ground-source heat pumps (GSHPs), have been proven capable of significantly reducing energy use and peak demand in buildings. Conventional equipment for controlling the temperature and humidity of a building, or supplying hot water and fresh outdoor air, must exchange energy (or heat) with the building's outdoor environment. Equipment using the ground as a heat source and heat sink consumes less non-renewable energy (electricity and fossil fuels) because the earth is cooler than outdoor air in summer and warmer in winter. The most important barrier to rapid growth of the GSHP industry is high first cost of GSHP systems to consumers. The most common GSHP system utilizes a closed-loop ground heat exchanger. This type of GSHP system can be used almost anywhere. There is reason to believe that reducing the cost of closed-loop systems is the strategy that would achieve the greatest energy savings with GSHP technology. The cost premium of closed-loop GSHP systems over conventional space conditioning and water heating systems is primarily associated with drilling boreholes or excavating trenches, installing vertical or horizontal ground heat exchangers, and backfilling the excavations. This project investigates reducing the cost of horizontal closed-loop ground heat exchangers by installing them in the construction excavations, augmented when necessary with additional trenches. This approach applies only to new construction of residential and light commercial buildings or additions to such buildings. In the business-as-usual scenario, construction excavations are not used for the horizontal ground heat exchanger (HGHX); instead the HGHX is installed entirely in trenches dug specifically for that purpose. The potential cost savings comes from using the construction excavations for the installation of ground heat exchangers, thereby minimizing the need and expense of digging additional trenches. The term foundation heat exchanger (FHX) has been coined to refer exclusively to ground heat exchangers installed in the overcut around the basement walls. The primary technical challenge undertaken by this project was the development and validation of energy performance models and design tools for FHX. In terms of performance modeling and design, ground heat exchangers in other construction excavations (e.g., utility trenches) are no different from conventional HGHX, and models and design tools for HGHX already exist. This project successfully developed and validated energy performance models and design tools so that FHX or hybrid FHX/HGHX systems can be engineered with confidence, enabling this technology to be applied in residential and light commercial buildings. The validated energy performance model also addresses and solves another problem, the longstanding inadequacy in the way ground-building thermal interaction is represented in building energy models, whether or not there is a ground heat exchanger nearby. Two side-by-side, three-level, unoccupied research houses with walkout basements, identical 3,700 ft{sup 2} floor plans, and hybrid FHX/HGHX systems were constructed to provide validation data sets for the energy performance model and design tool. The envelopes of both houses are very energy efficient and airtight, and the HERS ratings of the homes are 44 and 45 respectively. Both houses are mechanically ventilated with energy recovery ventilators, with space conditioning provided by water-to-air heat pumps with 2 ton nominal capacities. Separate water-to-water heat pumps with 1.5 ton nominal capacities were used for water heating. In these unoccupied research houses, human impact on energy use (hot water draw, etc.) is simulated to match the national average. At House 1 the hybrid FHX/HGHX system was installed in 300 linear feet of excavation, and 60% of that was construction excavation (needed to construct the home). At House 2 the hybrid FHX/HGHX system was installed in 360 feet of excavation, 50% of which was construction excavation. There are six pipes in all excavations (three par

Hughes, Patrick [ORNL; Im, Piljae [ORNL

2012-01-01T23:59:59.000Z

303

Modeling and Simulation of HVAC Faulty Operations and Performance Degradation due to Maintenance Issues  

SciTech Connect (OSTI)

Almost half of the total energy used in the U.S. buildings is consumed by heating, ventilation and air conditionings (HVAC) according to EIA statistics. Among various driving factors to energy performance of building, operations and maintenance play a significant role. Many researches have been done to look at design efficiencies and operational controls for improving energy performance of buildings, but very few study the impacts of HVAC systems maintenance. Different practices of HVAC system maintenance can result in substantial differences in building energy use. If a piece of HVAC equipment is not well maintained, its performance will degrade. If sensors used for control purpose are not calibrated, not only building energy usage could be dramatically increased, but also mechanical systems may not be able to satisfy indoor thermal comfort. Properly maintained HVAC systems can operate efficiently, improve occupant comfort, and prolong equipment service life. In the paper, maintenance practices for HVAC systems are presented based on literature reviews and discussions with HVAC engineers, building operators, facility managers, and commissioning agents. We categorize the maintenance practices into three levels depending on the maintenance effort and coverage: 1) proactive, performance-monitored maintenance; 2) preventive, scheduled maintenance; and 3) reactive, unplanned or no maintenance. A sampled list of maintenance issues, including cooling tower fouling, boiler/chiller fouling, refrigerant over or under charge, temperature sensor offset, outdoor air damper leakage, outdoor air screen blockage, outdoor air damper stuck at fully open position, and dirty filters are investigated in this study using field survey data and detailed simulation models. The energy impacts of both individual maintenance issue and combined scenarios for an office building with central VAV systems and central plant were evaluated by EnergyPlus simulations using three approaches: 1) direct modeling with EnergyPlus, 2) using the energy management system feature of EnergyPlus, and 3) modifying EnergyPlus source code. The results demonstrated the importance of maintenance for HVAC systems on energy performance of buildings. The research is intended to provide a guideline to help practitioners and building operators to gain the knowledge of maintaining HVAC systems in efficient operations, and prioritize HVAC maintenance work plan. The paper also discusses challenges of modeling building maintenance issues using energy simulation programs.

Wang, Liping; Hong, Tianzhen

2013-01-01T23:59:59.000Z

304

Lagrangian and Control Volume Models for Prediction of Cooling Lake Performance at SRP  

SciTech Connect (OSTI)

The model validation described in this document indicates that the methods described here and by Cooper (1984) for predicting the performance of the proposed L-Area cooling lake are reliable. Extensive observations from the Par Pond system show that lake surface temperatures exceeding 32.2 degrees C (90 degrees F) are attained occasionally in the summer in areas where there is little or no heating from the P-Area Reactor. Regulations which restrict lake surface temperatures to less than 32.2 degrees C should be structured to allow for these naturally-occurring thermal excursions.

Garrett, A.J.

2001-06-26T23:59:59.000Z

305

Renewable Power Options for Electrical Generation on Kaua'i: Economics and Performance Modeling  

SciTech Connect (OSTI)

The Hawaii Clean Energy Initiative (HCEI) is working with a team led by the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to assess the economic and technical feasibility of increasing the contribution of renewable energy in Hawaii. This part of the HCEI project focuses on working with Kaua'i Island Utility Cooperative (KIUC) to understand how to integrate higher levels of renewable energy into the electric power system of the island of Kaua'i. NREL partnered with KIUC to perform an economic and technical analysis and discussed how to model PV inverters in the electrical grid.

Burman, K.; Keller, J.; Kroposki, B.; Lilienthal, P.; Slaughter, R.; Glassmire, J.

2011-11-01T23:59:59.000Z

306

A model study of the performance of water-driven anticlinal reservoirs  

E-Print Network [OSTI]

, Dykstra, H. and Parsons, R. L. : "The Prediction of Oil Recovery by Waterflood, " Seconder Recover of Oil in the 0 't d St t API S d Edtd 0, (5050) P. Idd. 4. Dyes, A. B. : "Production of W'ster-Driven Reservoirs Below Their Bubble Point, " Tran...A MODEL STUDY OF THE PERFORMANCE OF WATER-DRIVEN ANTICLINAL RESERVOIRS A Thesis By ALVIN W. TALASH Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree...

Talash, Alvin Wesley

1960-01-01T23:59:59.000Z

307

Performance of corrosion inhibiting admixtures for structural concrete -- assessment methods and predictive modeling  

SciTech Connect (OSTI)

During the past fifteen years corrosion inhibiting admixtures (CIAs) have become increasingly popular for protection of reinforced components of highway bridges and other structures from damage induced by chlorides. However, there remains considerable debate about the benefits of CIAs in concrete. A variety of testing methods to assess the performance of CIA have been reported in the literature, ranging from tests in simulated pore solutions to long-term exposures of concrete slabs. The paper reviews the published techniques and recommends the methods which would make up a comprehensive CIA effectiveness testing program. The results of this set of tests would provide the data which can be used to rank the presently commercially available CIA and future candidate formulations utilizing a proposed predictive model. The model is based on relatively short-term laboratory testing and considers several phases of a service life of a structure (corrosion initiation, corrosion propagation without damage, and damage to the structure).

Yunovich, M.; Thompson, N.G. [CC Technologies Labs., Inc., Dublin, OH (United States)

1998-12-31T23:59:59.000Z

308

PORFLOW MODELING FOR A PRELIMINARY ASSESSMENT OF THE PERFORMANCE OF NEW SALTSTONE DISPOSAL UNIT DESIGNS  

SciTech Connect (OSTI)

At the request of Savannah River Remediation (SRR), SRNL has analyzed the expected performance obtained from using seven 32 million gallon Saltstone Disposal Units (SDUs) in the Z-Area Saltstone Disposal Facility (SDF) to store future saltstone grout. The analysis was based on preliminary SDU final design specifications. The analysis used PORFLOW modeling to calculate the release of 20 radionuclides from an SDU and transport of the radionuclides and daughters through the vadose zone. Results from this vadose zone analysis were combined with previously calculated releases from existing saltstone vaults and FDCs and a second PORFLOW model run to calculate aquifer transport to assessment points located along a boundary 100 m from the nearest edge of the SDF sources. Peak concentrations within 12 sectors spaced along the 100 m boundary were determined over a period of evaluation extending 20,000 years after SDF closure cap placement. These peak concentrations were provided to SRR to use as input for dose calculations.

Smith, F.

2012-08-06T23:59:59.000Z

309

Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: I. Along-channel Water Level Variations, Pacific Ocean to Bonneville Dam  

SciTech Connect (OSTI)

This two-part paper provides comprehensive time and frequency domain analyses and models of along-channel water level variations in the 234km-long Lower Columbia River and Estuary (LCRE) and documents the response of floodplain wetlands thereto. In Part I, power spectra, continuous wavelet transforms, and harmonic analyses are used to understand the influences of tides, river flow, upwelling and downwelling, and hydropower operations ("power-peaking") on the water level regime. Estuarine water levels are influenced primarily by astronomical tides and coastal processes, and secondarily by river flow. The importance of coastal and tidal influences decreases in the landward direction, and water levels are increasingly controlled by river flow variations at periods from ?1day to years. Water level records are only slightly non-stationary near the ocean, but become increasingly irregular upriver. Although astronomically forced tidal constituents decrease above the estuary, tidal fortnightly and overtide variations increase for 80-200km landward, both relative to major tidal constituents and in absolute terms.

Jay, D. A.; Leffler, K.; Diefenderfer, Heida L.; Borde, Amy B.

2014-06-07T23:59:59.000Z

310

MHK Projects/BW2 Tidal | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 Tidal < MHK Projects Jump to:

311

MHK Projects/Cape May Tidal Energy | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 Tidal <CETO La ReunionCape

312

MHK Projects/Cuttyhunk Tidal Energy Plant | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 Tidal <CETOCohanseyHub <

313

MHK Projects/Deception Pass Tidal Energy Hydroelectric Project | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 Tidal

314

MHK Projects/Dorchester Maurice Tidal | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 TidalMar Landing <

315

MHK Projects/East Foreland Tidal Energy | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 TidalMar Landing <DouglasForeland

316

MHK Projects/Gastineau Channel Tidal | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAK Technologies Jump to:BW2 TidalMarFalmouthVinalhaven ME

317

MHK Projects/Wiscasset Tidal Energy Plant | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IE < MHKInformation BretonMOWiscasset Tidal

318

MHK Technologies/Deep Gen Tidal Turbines | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IE <AirWEC < MHK<Tidal Turbines < MHK

319

MHK Technologies/KESC Tidal Generator | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IE <AirWECHelix <IWAVE < MHKKESC Tidal

320

MHK Technologies/Rotech Tidal Turbine RTT | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IEOWC < MHKPulse-Stream 120 < MHKRotech Tidal

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

MHK Technologies/Tidal Barrage | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IEOWC <SurgeWEC <Generator.jpgTheTidal

322

MHK Technologies/Tidal Delay | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IEOWC <SurgeWEC <Generator.jpgTheTidalDelay

323

MHK Technologies/Tidal Hydraulic Generators THG | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revision hasInformation Earth's Heat JumpIncMAKGalway Bay IEOWC <SurgeWEC <Generator.jpgTheTidalDelayTHG

324

Hydra Tidal Energy Technology AS | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHiCalifornia: Energy ResourcesPark,is aHy9Hydesville,Hydra Tidal

325

Coupling a transient solvent extraction module with the separations and safeguards performance model.  

SciTech Connect (OSTI)

A number of codes have been developed in the past for safeguards analysis, but many are dated, and no single code is able to cover all aspects of materials accountancy, process monitoring, and diversion scenario analysis. The purpose of this work was to integrate a transient solvent extraction simulation module developed at Oak Ridge National Laboratory, with the Separations and Safeguards Performance Model (SSPM), developed at Sandia National Laboratory, as a first step toward creating a more versatile design and evaluation tool. The SSPM was designed for materials accountancy and process monitoring analyses, but previous versions of the code have included limited detail on the chemical processes, including chemical separations. The transient solvent extraction model is based on the ORNL SEPHIS code approach to consider solute build up in a bank of contactors in the PUREX process. Combined, these capabilities yield a more robust transient separations and safeguards model for evaluating safeguards system design. This coupling and initial results are presented. In addition, some observations toward further enhancement of separations and safeguards modeling based on this effort are provided, including: items to be addressed in integrating legacy codes, additional improvements needed for a fully functional solvent extraction module, and recommendations for future integration of other chemical process modules.

DePaoli, David W. (Oak Ridge National Laboratory, Oak Ridge, TN); Birdwell, Joseph F. (Oak Ridge National Laboratory, Oak Ridge, TN); Gauld, Ian C. (Oak Ridge National Laboratory, Oak Ridge, TN); Cipiti, Benjamin B.; de Almeida, Valmor F. (Oak Ridge National Laboratory, Oak Ridge, TN)

2009-10-01T23:59:59.000Z

326

Summary Results for Brine Migration Modeling Performed by LANL LBNL and SNL for the UFD Program  

SciTech Connect (OSTI)

This report summarizes laboratory and field observations and numerical modeling related to coupled processes involving brine and vapor migration in geologic salt, focusing on recent developments and studies conducted at Sandia, Los Alamos, and Berkeley National Laboratories. Interest into the disposal of heat-generating waste in salt has led to interest into water distribution and migration in both run-of-mine crushed and intact geologic salt. Ideally a fully coupled thermal-hydraulic-mechanical-chemical simulation is performed using numerical models with validated constitutive models and parameters. When mechanical coupling is not available, mechanical effects are prescribed in hydraulic models as source, boundary, or initial conditions. This report presents material associated with developing appropriate initial conditions for a non-mechanical hydrologic simulation of brine migration in salt. Due to the strong coupling between the mechanical and hydrologic problems, the initial saturation will be low for the excavation disturbed zone surrounding the excavation. Although most of the material in this report is not new, the author hopes it is presented in a format making it useful to other salt researchers.

Kuhlman, Kristopher L.

2014-09-01T23:59:59.000Z

327

Improving thermosyphon solar domestic hot water system model performance. Final report, March 1994--February 1995  

SciTech Connect (OSTI)

Data from an indoor solar simulator experimental performance test is used to develop a systematic calibration procedure for a computer model of a thermosyphoning, solar domestic hot water heating system with a tank-in-tank heat exchanger. Calibration is performed using an indoor test with a simulated solar collector to adjust heat transfer in the heat exchanger and heat transfer between adjacent layers of water in the storage tank. An outdoor test is used to calibrate the calculation of the friction drop in the closed collector loop. Additional indoor data with forced flow in the annulus of the heat exchanger leads to improved heat transfer correlations for the inside and outside regions of the tank-in-tank heat exchanger. The calibrated simulation model is compared to several additional outdoor tests both with and without auxiliary heating. Integrated draw energies are predicted with greater accuracy and draw temperature profiles match experimental results to a better degree. Auxiliary energy input predictions improve significantly. 63 figs., 29 tabs.

Swift, T.N.

1996-09-01T23:59:59.000Z

328

Performance Task using Video Analysis and Modelling to promote K12 eight practices of science  

E-Print Network [OSTI]

We will share on the use of Tracker as a pedagogical tool in the effective learning and teaching of physics performance tasks taking root in some Singapore Grade 9 (Secondary 3) schools. We discuss the pedagogical use of Tracker help students to be like scientists in these 6 to 10 weeks where all Grade 9 students are to conduct a personal video analysis and where appropriate the 8 practices of sciences (1. ask question, 2. use models, 3. Plan and carry out investigation, 4. Analyse and interpret data, 5. Using mathematical and computational thinking, 6. Construct explanations, 7. Discuss from evidence and 8. Communicating information). We will situate our sharing on actual students work and discuss how tracker could be an effective pedagogical tool. Initial research findings suggest that allowing learners conduct performance task using Tracker, a free open source video analysis and modelling tool, guided by the 8 practices of sciences and engineering, could be an innovative and effective way to mentor authent...

Wee, Loo Kang

2015-01-01T23:59:59.000Z

329

Performance Evaluation of O-Ring Seals in Model 9975 Packaging Assemblies (U)  

SciTech Connect (OSTI)

The Materials Consultation Group of SRTC has completed a review of existing literature and data regarding the useable service life of Viton{reg_sign} GLT fluoroelastomer O-rings currently used in the Model 9975 packaging assemblies. Although the shipping and transportation period is normally limited to 2 years, it is anticipated that these packages will be used for longer-term storage of Pu-bearing materials in KAMS (K-Area Materials Storage) prior to processing or disposition in the APSF (Actinide Packaging and Storage Facility). Based on the service conditions and review of available literature, Materials Consultation concludes that there is sufficient existing data to establish the technical basis for storage of Pu-bearing materials using Parker Seals O-ring compound V835-75 (or equivalent) for up to 10 years following the 2-year shipping period. Although significant physical deterioration of the O-rings and release of product is not expected, definite changes in physical properties will occur. However, due to the complex relationship between elastomer formulation, seal properties, and competing degradation mechanisms, the actual degree of property variation and impact upon seal performance is difficult to predict. Therefore, accelerated aging and/or surveillance programs are recommended to validate the assumptions outlined in this report and to assess the long-term performance of O-ring seals under actual service conditions. Such programs could provide a unique opportunity to develop nonexistent long-term performance data, as well as address storage extension issues if necessary.

Skidmore, Eric

1998-12-28T23:59:59.000Z

330

Nuclear Energy Advanced Modeling and Simulation (NEAMS) waste Integrated Performance and Safety Codes (IPSC) : gap analysis for high fidelity and performance assessment code development.  

SciTech Connect (OSTI)

This report describes a gap analysis performed in the process of developing the Waste Integrated Performance and Safety Codes (IPSC) in support of the U.S. Department of Energy (DOE) Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign. The goal of the Waste IPSC is to develop an integrated suite of computational modeling and simulation capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive waste storage or disposal system. The Waste IPSC will provide this simulation capability (1) for a range of disposal concepts, waste form types, engineered repository designs, and geologic settings, (2) for a range of time scales and distances, (3) with appropriate consideration of the inherent uncertainties, and (4) in accordance with rigorous verification, validation, and software quality requirements. The gap analyses documented in this report were are performed during an initial gap analysis to identify candidate codes and tools to support the development and integration of the Waste IPSC, and during follow-on activities that delved into more detailed assessments of the various codes that were acquired, studied, and tested. The current Waste IPSC strategy is to acquire and integrate the necessary Waste IPSC capabilities wherever feasible, and develop only those capabilities that cannot be acquired or suitably integrated, verified, or validated. The gap analysis indicates that significant capabilities may already exist in the existing THC codes although there is no single code able to fully account for all physical and chemical processes involved in a waste disposal system. Large gaps exist in modeling chemical processes and their couplings with other processes. The coupling of chemical processes with flow transport and mechanical deformation remains challenging. The data for extreme environments (e.g., for elevated temperature and high ionic strength media) that are needed for repository modeling are severely lacking. In addition, most of existing reactive transport codes were developed for non-radioactive contaminants, and they need to be adapted to account for radionuclide decay and in-growth. The accessibility to the source codes is generally limited. Because the problems of interest for the Waste IPSC are likely to result in relatively large computational models, a compact memory-usage footprint and a fast/robust solution procedure will be needed. A robust massively parallel processing (MPP) capability will also be required to provide reasonable turnaround times on the analyses that will be performed with the code. A performance assessment (PA) calculation for a waste disposal system generally requires a large number (hundreds to thousands) of model simulations to quantify the effect of model parameter uncertainties on the predicted repository performance. A set of codes for a PA calculation must be sufficiently robust and fast in terms of code execution. A PA system as a whole must be able to provide multiple alternative models for a specific set of physical/chemical processes, so that the users can choose various levels of modeling complexity based on their modeling needs. This requires PA codes, preferably, to be highly modularized. Most of the existing codes have difficulties meeting these requirements. Based on the gap analysis results, we have made the following recommendations for the code selection and code development for the NEAMS waste IPSC: (1) build fully coupled high-fidelity THCMBR codes using the existing SIERRA codes (e.g., ARIA and ADAGIO) and platform, (2) use DAKOTA to build an enhanced performance assessment system (EPAS), and build a modular code architecture and key code modules for performance assessments. The key chemical calculation modules will be built by expanding the existing CANTERA capabilities as well as by extracting useful components from other existing codes.

Lee, Joon H.; Siegel, Malcolm Dean; Arguello, Jose Guadalupe, Jr.; Webb, Stephen Walter; Dewers, Thomas A.; Mariner, Paul E.; Edwards, Harold Carter; Fuller, Timothy J.; Freeze, Geoffrey A.; Jove-Colon, Carlos F.; Wang, Yifeng

2011-03-01T23:59:59.000Z

331

Evidence for tidal interaction and merger as the origin of galaxy morphology evolution in compact groups  

E-Print Network [OSTI]

We present the results of a morphological study based on NIR images of 25 galaxies, with different levels of nuclear activity, in 8 Compact Groups of Galaxies (CGs). We perform independently two different analysis: a isophotal study and a study of morphological asymmetries. The results yielded by the two analysis are highly consistent. For the first time, it is possible to show that deviations from pure ellipses are produced by inhomogeneous stellar mass distributions related to galaxy interactions and mergers. We find evidence of mass asymmetries in 74% of the galaxies in our sample. In 59% of these cases, the asymmetries come in pairs, and are consistent with tidal effects produced by the proximity of companion galaxies. The symmetric galaxies are generally small in size or mass, inactive, and have an early-type morphology. In 20% of the galaxies we find evidence for cannibalism. In 36% of the early-type galaxies the color gradient is positive (blue nucleus) or flat. Summing up these results, as much as 52% of the galaxies in our sample could show evidence of an on going or past mergers. Our observations suggest that galaxies in CGs merge more frequently under ``dry'' conditions. The high frequency of interacting and merging galaxies observed in our study is consistent with the bias of our sample towards CGs of type B, which represents the most active phase in the evolution of the groups. In these groups we also find a strong correlation between asymmetries and nuclear activity in early-type galaxies. This correlation allows us to identify tidal interactions and mergers as the cause of galaxy morphology transformation in CGs.[abridge

R. Coziol; I. Plauchu-Frayn

2007-02-10T23:59:59.000Z

332

A Tidal Hydrology Assessment for Reconnecting Spring Branch Creek to Suisun Marsh, Solano County CA: Predicting the Impact to the Federally Listed Plant Soft Bird's Beak  

E-Print Network [OSTI]

this study. Changes in hydrology are not the only potentialA Tidal Hydrology Assessment for Reconnecting Spring Branchmay change the tidal hydrology and impact the area occupied

Olson, Jessica J.

2011-01-01T23:59:59.000Z

333

Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid  

E-Print Network [OSTI]

Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid by Susan Margot Boronowski Committee Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid by Susan Margot, Canada that relies heavily on diesel fuel for energy generation. An investigation is done

Victoria, University of

334

Cross-shore sediment transport and the equilibrium morphology of mudflats under tidal currents  

E-Print Network [OSTI]

Cross-shore sediment transport and the equilibrium morphology of mudflats under tidal currents D of suspended sediment transport under cross-shore tidal currents on an intertidal mudflat. We employ a Lagrangian formulation to obtain periodic solutions for the sediment transport over idealized bathymetries

Hogg, Andrew

335

Intracranial Pressure Variation Associated with Changes in End-Tidal CO2  

E-Print Network [OSTI]

Intracranial Pressure Variation Associated with Changes in End-Tidal CO2 Sunghan Kim, James Mc that the partial pressure of arterial CO2 (PaCO2) can affect cerebral blood flow, cerebral blood volume, and therefore ICP. The end-tidal CO2 (ETCO2) is usually monitored by clinicians as a proxy for PaCO2. We show

336

Mercury Dynamics in a San Francisco Estuary Tidal Wetland: Assessing Dynamics Using In Situ Measurements  

E-Print Network [OSTI]

Mercury Dynamics in a San Francisco Estuary Tidal Wetland: Assessing Dynamics Using In Situ the tidally driven exchange of mercury (Hg) between the waters of the San Francisco estuary and Browns Island, respectively--together predicted 94 % of the observed variability in measured total mercury concentra- tion

Boss, Emmanuel S.

337

The Magellanic Bridge: The Nearest Purely Tidal Stellar Population  

E-Print Network [OSTI]

We report on observations of the stellar populations in twelve fields spanning the region between the Magellanic Clouds, made with the Mosaic-II camera on the 4-meter telescope at the Cerro-Tololo Inter-American Observatory. The two main goals of the observations are to characterize the young stellar population (which presumably formed in situ in the Bridge and therefore represents the nearest stellar population formed from tidal debris), and to search for an older stellar component (which would have been stripped from either Cloud as stars, by the same tidal forces which formed the gaseous Bridge). We determine the star-formation history of the young inter-Cloud population, which provides a constraint on the timing of the gravitational interaction which formed the Bridge. We do not detect an older stellar population belonging to the Bridge in any of our fields, implying that the material that was stripped from the Clouds to form the Magellanic Bridge was very nearly a pure gas.

Jason Harris

2006-12-04T23:59:59.000Z

338

Dynamical resonance locking in tidally interacting binary systems  

E-Print Network [OSTI]

We examine the dynamics of resonance locking in detached, tidally interacting binary systems. In a resonance lock, a given stellar or planetary mode is trapped in a highly resonant state for an extended period of time, during which the spin and orbital frequencies vary in concert to maintain the resonance. This phenomenon is qualitatively similar to resonance capture in planetary dynamics. We show that resonance locks can accelerate the course of tidal evolution in eccentric systems and also efficiently couple spin and orbital evolution in circular binaries. Previous analyses of resonance locking have not treated the mode amplitude as a fully dynamical variable, but rather assumed the adiabatic (i.e. Lorentzian) approximation valid only in the limit of relatively strong mode damping. We relax this approximation, analytically derive conditions under which the fixed point associated with resonance locking is stable, and further check these analytic results using numerical integrations of the coupled mode, spin, and orbital evolution equations. These show that resonance locking can sometimes take the form of complex limit cycles or even chaotic trajectories. We provide simple analytic formulae that define the binary and mode parameter regimes in which resonance locks of some kind occur (stable, limit cycle, or chaotic). We briefly discuss the astrophysical implications of our results for white dwarf and neutron star binaries as well as eccentric stellar binaries.

Joshua Burkart; Eliot Quataert; Phil Arras

2014-10-25T23:59:59.000Z

339

Literature Review and Assessment of Plant and Animal Transfer Factors Used in Performance Assessment Modeling  

SciTech Connect (OSTI)

A literature review and assessment was conducted by Pacific Northwest National Laboratory (PNNL) to update information on plant and animal radionuclide transfer factors used in performance-assessment modeling. A group of 15 radionuclides was included in this review and assessment. The review is composed of four main sections, not including the Introduction. Section 2.0 provides a review of the critically important issue of physicochemical speciation and geochemistry of the radionuclides in natural soil-water systems as it relates to the bioavailability of the radionuclides. Section 3.0 provides an updated review of the parameters of importance in the uptake of radionuclides by plants, including root uptake via the soil-groundwater system and foliar uptake due to overhead irrigation. Section 3.0 also provides a compilation of concentration ratios (CRs) for soil-to-plant uptake for the 15 selected radionuclides. Section 4.0 provides an updated review on radionuclide uptake data for animal products related to absorption, homeostatic control, approach to equilibration, chemical and physical form, diet, and age. Compiled transfer coefficients are provided for cow’s milk, sheep’s milk, goat’s milk, beef, goat meat, pork, poultry, and eggs. Section 5.0 discusses the use of transfer coefficients in soil, plant, and animal modeling using regulatory models for evaluating radioactive waste disposal or decommissioned sites. Each section makes specific suggestions for future research in its area.

Robertson, David E.; Cataldo, Dominic A.; Napier, Bruce A.; Krupka, Kenneth M.; Sasser, Lyle B.

2003-07-20T23:59:59.000Z

340

The Effect of Tidal Inflation Instability on the Mass and Dynamical Evolution of Extrasolar Planets with Ultra-Short Periods  

E-Print Network [OSTI]

We investigate the possibility of substantial inflation of short-period Jupiter-mass planets, as a result of their internal tidal dissipation associated with the synchronization and circularization of their orbits. We employ the simplest prescription based on an equilibrium model with a constant lag angle for all components of the tide. We show that for young Jupiter-mass planets, with a period less than 3 days, an initial radius about 2 Jupiter radii, and an orbital eccentricity greater than 0.2, the energy dissipated during the circularization of their orbits is sufficiently intense and protracted to inflate their sizes up to their Roche radii.

Pin-Gao Gu; Doug Lin; Peter Bodenheimer

2003-03-17T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Tidal Waves -- a non-adiabatic microscopic description of the yrast states in near-spherical nuclei  

E-Print Network [OSTI]

The yrast states of nuclei that are spherical or weakly deformed in their ground states are described as quadrupole waves running over the nuclear surface, which we call "tidal waves". The energies and E2 transition probabilities of the yrast states in nuclides with $Z$= 44, 46, 48 and $N=56, ~58,..., 66$ are calculated by means of the cranking model in a microscopic way. The nonlinear response of the nucleonic orbitals results in a strong coupling between shape and single particle degrees of freedom.

S. Frauendorf; Y. Gu; J. Sun

2011-09-08T23:59:59.000Z

342

Model-Driven Dashboards for Business Performance Reporting Pawan Chowdhary, Themis Palpanas, Florian Pinel, Shyh-Kwei Chen, Frederick Y. Wu  

E-Print Network [OSTI]

Model-Driven Dashboards for Business Performance Reporting Pawan Chowdhary, Themis Palpanas, skchen, fywu}@us.ibm.com Abstract Business performance modeling and model-driven business transformation an approach for dashboard development that is model-driven and can be integrated with the business performance

Palpanas, Themis

343

TRISO-Fuel Element Performance Modeling for the Hybrid LIFE Engine with Pu Fuel Blanket  

SciTech Connect (OSTI)

A TRISO-coated fuel thermo-mechanical performance study is performed for the hybrid LIFE engine to test the viability of TRISO particles to achieve ultra-high burnup of a weapons-grade Pu blanket. Our methodology includes full elastic anisotropy, time and temperature varying material properties for all TRISO layers, and a procedure to remap the elastic solutions in order to achieve fast fluences up to 30 x 10{sup 25} n {center_dot} m{sup -2} (E > 0.18 MeV). In order to model fast fluences in the range of {approx} 7 {approx} 30 x 10{sup 25} n {center_dot} m{sup -2}, for which no data exist, careful scalings and extrapolations of the known TRISO material properties are carried out under a number of potential scenarios. A number of findings can be extracted from our study. First, failure of the internal pyrolytic carbon (PyC) layer occurs within the first two months of operation. Then, the particles behave as BISO-coated particles, with the internal pressure being withstood directly by the SiC layer. Later, after 1.6 years, the remaining PyC crumbles due to void swelling and the fuel particle becomes a single-SiC-layer particle. Unrestrained by the PyC layers, and at the temperatures and fluences in the LIFE engine, the SiC layer maintains reasonably-low tensile stresses until the end-of-life. Second, the PyC creep constant, K, has a striking influence on the fuel performance of TRISO-coated particles, whose stresses scale almost inversely proportional to K. Obtaining more reliable measurements, especially at higher fluences, is an imperative for the fidelity of our models. Finally, varying the geometry of the TRISO-coated fuel particles results in little differences in the scope of fuel performance. The mechanical integrity of 2-cm graphite pebbles that act as fuel matrix has also been studied and it is concluded that they can reliable serve the entire LIFE burnup cycle without failure.

DeMange, P; Marian, J; Caro, M; Caro, A

2010-02-18T23:59:59.000Z

344

Result Summary for the Area 5 Radioactive Waste Management Site Performance Assessment Model Version 4.113  

SciTech Connect (OSTI)

Preliminary results for Version 4.113 of the Nevada National Security Site Area 5 Radioactive Waste Management Site performance assessment model are summarized. Version 4.113 includes the Fiscal Year 2011 inventory estimate.

Shott, G. J.

2012-04-15T23:59:59.000Z

345

Comparison of Demand Response Performance with an EnergyPlus Model in a Low Energy Campus Building  

E-Print Network [OSTI]

of Automated Demand Response in a Large Office Building”, inBuilding Control Strategies and Techniques for Demand Response.Demand Response Performance with an EnergyPlus Model in a Low Energy Campus Building

Dudley, Junqiao Han

2010-01-01T23:59:59.000Z

346

TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket  

E-Print Network [OSTI]

Quantification in Fuel Performance Modeling . . . . . . .3.4 Integration with Fuel Performance Calculations ivmicroscopic image of a TRISO fuel particle cracked open to

Powers, Jeffrey

2011-01-01T23:59:59.000Z

347

Tidal deformation of a slowly rotating material body. I. External metric  

E-Print Network [OSTI]

We construct the external metric of a slowly rotating, tidally deformed material body in general relativity. The tidal forces acting on the body are assumed to be weak and to vary slowly with time, and the metric is obtained as a perturbation of a background metric that describes the external geometry of an isolated, slowly rotating body. The tidal environment is generic and characterized by two symmetric-tracefree tidal moments E_{ab} and B_{ab}, and the body is characterized by its mass M, its radius R, and a dimensionless angular-momentum vector \\chi^a environment requires the introduction of four new quantities, which we designate as rotational-tidal Love numbers. All these Love numbers are gauge ...

Landry, Philippe

2015-01-01T23:59:59.000Z

348

Determination of Electrochemical Performance and Thermo-Mechanical-Chemical Stability of SOFCs from Defect Modeling  

SciTech Connect (OSTI)

This research was focused on two distinct but related issues. The first issue concerned using defect modeling to understand the relationship between point defect concentration and the electrochemical, thermo-chemical and mechano-chemical properties of typical solid oxide fuel cell (SOFC) materials. The second concerned developing relationships between the microstructural features of SOFC materials and their electrochemical performance. To understand the role point defects play in ceramics, a coherent analytical framework was used to develop expressions for the dependence of thermal expansion and elastic modulus on point defect concentration in ceramics. These models, collectively termed the continuum-level electrochemical model (CLEM), were validated through fits to experimental data from electrical conductivity, I-V characteristics, elastic modulus and thermo-chemical expansion experiments for (nominally pure) ceria, gadolinia-doped ceria (GDC) and yttria-stabilized zirconia (YSZ) with consistently good fits. The same values for the material constants were used in all of the fits, further validating our approach. As predicted by the continuum-level electrochemical model, the results reveal that the concentration of defects has a significant effect on the physical properties of ceramic materials and related devices. Specifically, for pure ceria and GDC, the elastic modulus decreased while the chemical expansion increased considerably in low partial pressures of oxygen. Conversely, the physical properties of YSZ remained insensitive to changes in oxygen partial pressure within the studied range. Again, the findings concurred exactly with the predictions of our analytical model. Indeed, further analysis of the results suggests that an increase in the point defect content weakens the attractive forces between atoms in fluorite-structured oxides. The reduction treatment effects on the flexural strength and the fracture toughness of pure ceria were also evaluated at room temperature. The results reveal that the flexural strength decreases significantly after heat treatment in very low oxygen partial pressure environments; however, in contrast, fracture toughness is increased by 30-40% when the oxygen partial pressure was decreased to 10{sup -20} to 10{sup -22} atm range. Fractographic studies show that microcracks developed at 800 oC upon hydrogen reduction are responsible for the decreased strength. To understand the role of microstructure on electrochemical performance, electrical impedance spectra from symmetric LSM/YSZ/LSM cells was de-convoluted to obtain the key electrochemical components of electrode performance, namely charge transfer resistance, surface diffusion of reactive species and bulk gas diffusion through the electrode pores. These properties were then related to microstructural features, such as triple-phase boundary length and tortuosity. From these experiments we found that the impedance due to oxygen adsorption obeys a power law with pore surface area, while the impedance due to charge transfer is found to obey a power-law with respect to triple phase boundary length. A model based on kinetic theory explaining the power-law relationships observed was then developed. Finally, during our EIS work on the symmetric LSM/YSZ/LSM cells a technique was developed to improve the quality of high-frequency impedance data and their subsequent de-convolution.

Eric Wachsman; Keith L. Duncan

2006-09-30T23:59:59.000Z

349

An experimental study of heating performance and seasonal modeling of vertical U-tube ground coupled heat pumps  

E-Print Network [OSTI]

AN EXPERIMENTAL STUDY OF HEATING PERFORMANCE AND SEASONAL MODELING OF VERTICAL U-TUBE GROUND COUPLED HEAT PUMPS A Thesis by RANDAL E. MARGO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulftilment... of the requirements for the degree of MASTER OF SCIENCE December 1992 Major Subject: Mechanical Engineering AN EXPERIMENTAL STUDY OF HEATING PERFORMANCE AND SEASONAL MODELING OF VERTICAL U-TUBE GROUND COUPLED HEAT PUMPS A Thesis by RANDAL E. MARGO Approved...

Margo, Randal E.

1992-01-01T23:59:59.000Z

350

On the tidal interaction of massive extra-solar planets on highly eccentric orbit  

E-Print Network [OSTI]

In this paper we develop a theory of disturbances induced by the stellar tidal field in a fully convective slowly rotating planet orbiting on a highly eccentric orbit around a central star. We show that there are two contributions to the mode energy and angular momentum gain due to impulsive tidal interaction: a) 'the quasi-static' contribution which requires dissipative processes operating in the planet; b) the dynamical contribution associated with excitation of modes of oscillation. These contributions are obtained self-consistently from a single set of the governing equations. We calculate a critical 'equilibrium' value of angular velocity of the planet \\Omega_{crit} determined by the condition that action of the dynamical tides does not alter the angular velocity at that rotation rate. We show that this can be much larger than the corresponding rate associated with quasi-static tides and that at this angular velocity, the rate of energy exchange is minimised. We also investigate the conditions for the stochastic increase in oscillation energy that may occur if many periastron passages are considered. We make some simple estimates of time scale of circularization of initially eccentric orbit due to tides, using a realistic model of the planet, for orbits withperiods after circularization typical of those observed for extra-solar planets P_{obs} > 3days. We find that dynamic tides could have produced a very large decrease of the semi-major axis of a planet with mass of the order of the Jupiter mass M_{J} and final periods P_{obs} < 4.5days on a time-scale < a few Gyrs. We also discuss several unresolved issues in the context of the scenario of the orbit circularization due to dynamic tides.

P. B. Ivanov; J. C. B. Papaloizou

2003-10-09T23:59:59.000Z

351

The Use Of Computational Human Performance Modeling As Task Analysis Tool  

SciTech Connect (OSTI)

During a review of the Advanced Test Reactor safety basis at the Idaho National Laboratory, human factors engineers identified ergonomic and human reliability risks involving the inadvertent exposure of a fuel element to the air during manual fuel movement and inspection in the canal. There were clear indications that these risks increased the probability of human error and possible severe physical outcomes to the operator. In response to this concern, a detailed study was conducted to determine the probability of the inadvertent exposure of a fuel element. Due to practical and safety constraints, the task network analysis technique was employed to study the work procedures at the canal. Discrete-event simulation software was used to model the entire procedure as well as the salient physical attributes of the task environment, such as distances walked, the effect of dropped tools, the effect of hazardous body postures, and physical exertion due to strenuous tool handling. The model also allowed analysis of the effect of cognitive processes such as visual perception demands, auditory information and verbal communication. The model made it possible to obtain reliable predictions of operator performance and workload estimates. It was also found that operator workload as well as the probability of human error in the fuel inspection and transfer task were influenced by the concurrent nature of certain phases of the task and the associated demand on cognitive and physical resources. More importantly, it was possible to determine with reasonable accuracy the stages as well as physical locations in the fuel handling task where operators would be most at risk of losing their balance and falling into the canal. The model also provided sufficient information for a human reliability analysis that indicated that the postulated fuel exposure accident was less than credible.

Jacuqes Hugo; David Gertman

2012-07-01T23:59:59.000Z

352

Performance and cost models for the direct sulfur recovery process. Task 1 Topical report, Volume 3  

SciTech Connect (OSTI)

The purpose of this project is to develop performance and cost models of the Direct Sulfur Recovery Process (DSRP). The DSRP is an emerging technology for sulfur recovery from advanced power generation technologies such as Integrated Gasification Combined Cycle (IGCC) systems. In IGCC systems, sulfur present in the coal is captured by gas cleanup technologies to avoid creating emissions of sulfur dioxide to the atmosphere. The sulfur that is separated from the coal gas stream must be collected. Leading options for dealing with the sulfur include byproduct recovery as either sulfur or sulfuric acid. Sulfur is a preferred byproduct, because it is easier to handle and therefore does not depend as strongly upon the location of potential customers as is the case for sulfuric acid. This report describes the need for new sulfur recovery technologies.

Frey, H.C. [North Carolina State Univ., Raleigh, NC (United States); Williams, R.B. [Carneigie Mellon Univ., Pittsburgh, PA (United States)

1995-09-01T23:59:59.000Z

353

Low Cost Carbon Fibre: Applications, Performance and Cost Models - Chapter 17  

SciTech Connect (OSTI)

Weight saving in automotive applications has a major bearing on fuel economy. It is generally accepted that, typically, a 10% weight reduction in an automobile will lead to a 6-8% improvement in fuel economy. In this respect, carbon fibre composites are extremely attractive in their ability to provide superlative mechanical performance per unit weight. That is why they are specified for high-end uses such as Formula 1 racing cars and the latest aircraft (e.g. Boeing 787, Airbus A350 and A380), where they comprise over 50% by weight of the structure However, carbon fibres are expensive and this renders their composites similarly expensive. Research has been carried out at Oak Ridge National Laboratories (ORNL), Tennessee, USA for over a decade with the aim of reducing the cost of carbon fibre such that it becomes a cost-effective option for the automotive industry. Aspects of this research relating to the development of low cost carbon fibre have been reported in Chapter 3 of this publication. In this chapter, the practical industrial applications of low-cost carbon fibre are presented, together with considerations of the performance and cost models which underpin the work.

Warren, Charles David [ORNL; Wheatley, Dr. Alan [University of Sunderland; Das, Sujit [ORNL

2014-01-01T23:59:59.000Z

354

A combined wind wavetidal model for the Venice lagoon, Italy  

E-Print Network [OSTI]

A combined wind wave­tidal model for the Venice lagoon, Italy L. Carniello and A. Defina Department between waves and tide propagation. The combined wind wave­tidal model is applied to the Venice lagoon. Particular attention is devoted to the dissipation of wave energy at the steep boundaries between channels

Fagherazzi, Sergio

355

Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 3, Model parameters: Sandia WIPP Project  

SciTech Connect (OSTI)

This volume documents model parameters chosen as of July 1992 that were used by the Performance Assessment Department of Sandia National Laboratories in its 1992 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Ranges and distributions for about 300 modeling parameters in the current secondary data base are presented in tables for the geologic and engineered barriers, global materials (e.g., fluid properties), and agents that act upon the WIPP disposal system such as climate variability and human-intrusion boreholes. The 49 parameters sampled in the 1992 Preliminary Performance Assessment are given special emphasis with tables and graphics that provide insight and sources of data for each parameter.

Not Available

1992-12-29T23:59:59.000Z

356

Video Analysis and Modeling Performance Task to promote becoming like scientists in classrooms  

E-Print Network [OSTI]

This paper aims to share the use of Tracker a free open source video analysis and modeling tool that is increasingly used as a pedagogical tool for the effective learning and teaching of Physics for Grade 9 Secondary 3 students in Singapore schools to make physics relevant to the real world. We discuss the pedagogical use of Tracker, guided by the Framework for K-12 Science Education by National Research Council, USA to help students to be more like scientists. For a period of 6 to 10 weeks, students use a video analysis coupled with the 8 practices of sciences such as 1. Ask question, 2. Use models, 3. Plan and carry out investigation, 4. Analyse and interpret data, 5. Use mathematical and computational thinking, 6. Construct explanations, 7. Argue from evidence and 8. Communicate information. This papers focus in on discussing some of the performance task design ideas such as 3.1 flip video, 3.2 starting with simple classroom activities, 3.3 primer science activity, 3.4 integrative dynamics and kinematics l...

Wee, Loo Kang

2015-01-01T23:59:59.000Z

357

The modeling of the nuclear composition measurement performance of the Non-Imaging CHErenkov Array (NICHE)  

E-Print Network [OSTI]

In its initial deployment, the Non-Imaging CHErenkov Array (NICHE)will measure the flux and nuclear composition of cosmic rays from below 10^16 eV to 10^18 eV by using measurements of the amplitude and time-spread of the air-shower Cherenkov signal to achieve a robust event-by-event measurement of Xmax and energy. NICHE will have sufficient area and angular acceptance to have significant overlap with TA/TALE, within which NICHE is located, to allow for energy cross-calibration. In order to quantify NICHE's ability to measure the cosmic ray nuclear composition, 4-component composition models were constructed based upon a poly-gonato model of J. Hoerandel using simulated Xmax distributions of the composite composition as a function of energy. These composition distributions were then unfolded into individual components via an analysis technique that included NICHE's simulated Xmax and energy resolution performance as a function of energy as well as the effects of finite event statistics. Details of the construc...

Krizmanic, John; Sokolsky, Pierre

2013-01-01T23:59:59.000Z

358

CEMENTITIOUS BARRIERS MODELING FOR PERFORMANCE ASSESSMENTS OF SHALLOW LAND BURIAL OF LOW LEVEL RADIOACTIVE WASTE - 9243  

SciTech Connect (OSTI)

The Cementitious Barriers Partnership (CBP) was created to develop predictive capabilities for the aging of cementitious barriers over long timeframes. The CBP is a multi-agency, multi-national consortium working under a U.S. Department of Energy (DOE) Environmental Management (EM-21) funded Cooperative Research and Development Agreement (CRADA) with the Savannah River National Laboratory (SRNL) as the lead laboratory. Members of the CBP are SRNL, Vanderbilt University, the U.S. Nuclear Regulatory Commission (USNRC), National Institute of Standards and Technology (NIST), SIMCO Technologies, Inc. (Canada), and the Energy Research Centre of the Netherlands (ECN). A first step in developing advanced tools is to determine the current state-of-the-art. A review has been undertaken to assess the treatment of cementitious barriers in Performance Assessments (PA). Representatives of US DOE sites which have PAs for their low level waste disposal facilities were contacted. These sites are the Idaho National Laboratory, Oak Ridge National Laboratory, Los Alamos National Laboratory, Nevada Test Site, and Hanford. Several of the more arid sites did not employ cementitious barriers. Of those sites which do employ cementitious barriers, a wide range of treatment of the barriers in a PA was present. Some sites used conservative, simplistic models that even though conservative still showed compliance with disposal limits. Other sites used much more detailed models to demonstrate compliance. These more detailed models tend to be correlation-based rather than mechanistically-based. With the US DOE's Low Level Waste Disposal Federal Review Group (LFRG) moving towards embracing a risk-based, best estimate with an uncertainties type of analysis, the conservative treatment of the cementitious barriers seems to be obviated. The CBP is creating a tool that adheres to the LFRG chairman's paradigm of continuous improvement.

Taylor, G

2009-01-09T23:59:59.000Z

359

TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket.  

E-Print Network [OSTI]

??This study focused on creating a new tristructural isotropic (TRISO) coated particle fuel performance model and demonstrating the integration of this model into an existing… (more)

Powers, Jeffrey

2011-01-01T23:59:59.000Z

360

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007  

SciTech Connect (OSTI)

This document is the first annual report for the study titled “Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River.” Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council’s Columbia Basin Fish and Wildlife Program.

Sobocinski, Kathryn L.; Johnson, Gary E.; Sather, Nichole K.; Storch, Adam; Jones, Tucker A.; Mallette, Christine; Dawley, Earl M.; Skalski, John R.; Teel, David; Moran, Paul

2008-03-18T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

An examination of the construct validity of predictors of productive and counterproductive job performance using structural equation modeling  

E-Print Network [OSTI]

MODELING by JULIE ANNE GOODWiN TICE Submitted to the Office of Graduate Studies of Texas AkM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved to style and conte t by: Judith M. Col ' (Chair... Performance Using Structural Equation Modeling. (December 1996) Julie Anne Goodwm Tice, B. A. , Northwestern University Chair of Advisory Committee: Dr. Judith M. Collins This research used structural equation modeling to test the construct validity...

Tice, Julie Anne Goodwin

1996-01-01T23:59:59.000Z

362

Development of the integrated environmental control model: Performance models of selective catalytic reduction NO{sub x} control systems. Quarterly progress report, [April 1, 1993--June 30, 1993  

SciTech Connect (OSTI)

This report concerns the Integrated Environmental Control Model (IECM) created and enhanced by Carnegie Mellon University (CMU) for the US Department of Energy`s Pittsburgh Energy Technology Center (DOE/PETC). The IECM provides a capability to model various conventional and advanced processes for controlling air pollutant emissions from coal-fired power plants before, during, or after combustion. The principal purpose of the model is to calculate the performance, emissions, and cost of power plant configurations employing alternative environmental control methods. The model consists of various control technology modules, which may be integrated into a complete utility plant in any desired combination. In contrast to conventional deterministic models, the IECM offers the unique capability to assign probabilistic values to all model input parameters, and to obtain probabilistic outputs in the form of cumulative distribution functions indicating the likelihood of different costs and performance results.

Frey, H.C.

1993-07-01T23:59:59.000Z

363

SEVENTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE  

SciTech Connect (OSTI)

A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 54-72 months, which is still bounding to O-ring temperatures during storage in K-Area Complex (KAC). Based on expectations that the fixtures aging at 200 ºF will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at an intermediate temperature of 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 ºF. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 ºF for 30 - 36 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the O-rings displayed a compression set ranging from 51 – 96%. This is greater than seen to date for any packages inspected during KAC field surveillance (24% average). For GLT O-rings, separate service life estimates have been made based on the O-ring fixture leak test data and based on compression stress relaxation (CSR) data. These two predictive models show reasonable agreement at higher temperatures (350 – 400 ºF). However, at 300 ºF, the room temperature leak test failures to date experienced longer aging times than predicted by the CSRbased model. This suggests that extrapolations of the CSR model predictions to temperatures below 300 ºF will provide a conservative prediction of service life relative to the leak rate criterion. Leak test failure data at lower temperatures are needed to verify this apparent trend. Insufficient failure data exist currently to perform a similar comparison for GLT-S O-rings. Aging and periodic leak testing will continue for the remaining PCV O-ring fixtures.

Daugherty, W.

2012-08-30T23:59:59.000Z

364

Modeling and Simulation Environment for Photonic Interconnection Networks in High Performance Computing  

E-Print Network [OSTI]

at the scale of high performance computer clusters and warehouse scale data centers, system level simulations and results for rack scale photonic interconnection networks for high performance computing. Keywords: optical to the newsworthy power consumption [3], latency [4] and bandwidth challenges [5] of high performance computing (HPC

Bergman, Keren

365

Repository Integration Program: RIP performance assessment and strategy evaluation model theory manual and user`s guide  

SciTech Connect (OSTI)

This report describes the theory and capabilities of RIP (Repository Integration Program). RIP is a powerful and flexible computational tool for carrying out probabilistic integrated total system performance assessments for geologic repositories. The primary purpose of RIP is to provide a management tool for guiding system design and site characterization. In addition, the performance assessment model (and the process of eliciting model input) can act as a mechanism for integrating the large amount of available information into a meaningful whole (in a sense, allowing one to keep the ``big picture`` and the ultimate aims of the project clearly in focus). Such an integration is useful both for project managers and project scientists. RIP is based on a `` top down`` approach to performance assessment that concentrates on the integration of the entire system, and utilizes relatively high-level descriptive models and parameters. The key point in the application of such a ``top down`` approach is that the simplified models and associated high-level parameters must incorporate an accurate representation of their uncertainty. RIP is designed in a very flexible manner such that details can be readily added to various components of the model without modifying the computer code. Uncertainty is also handled in a very flexible manner, and both parameter and model (process) uncertainty can be explicitly considered. Uncertainty is propagated through the integrated PA model using an enhanced Monte Carlo method. RIP must rely heavily on subjective assessment (expert opinion) for much of its input. The process of eliciting the high-level input parameters required for RIP is critical to its successful application. As a result, in order for any project to successfully apply a tool such as RIP, an enormous amount of communication and cooperation must exist between the data collectors, the process modelers, and the performance. assessment modelers.

NONE

1995-11-01T23:59:59.000Z

366

Modeling and Simulation of HVAC Faulty Operations and Performance Degradation due to Maintenance Issues  

E-Print Network [OSTI]

of Commercial Building HVAC Systems, Atlanta: American2012. Modeling and simulation of HVAC faults in EnergyPlus,Modeling and Simulation of HVAC Faulty Operations and

Wang, Liping

2014-01-01T23:59:59.000Z

367

Division of Water, Parts 660-661: Tidal Wetlands (New York)  

Broader source: Energy.gov [DOE]

These regulations require permits for any activity which directly or indirectly may have a significant adverse effect on the existing condition of any tidal wetland, including but not limited to...

368

E-Print Network 3.0 - arterial-end tidal carbon Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

kWh range. Typical cost ranges include: Tidal generation - between 16 and 38pkWh Offshore wind - between 15... account of multiple factors for each generation type...

369

Groundwater response to dual tidal fluctuations in a peninsula or an elongated island  

E-Print Network [OSTI]

1 , Hongbin Zhan2,3, *, and Zhonghua Tang1 1 School of Environmental Studies, China University of the tidal fluctuations. This is called quasi-steady state condition *Correspondence to: Hongbin Zhan

Zhan, Hongbin

370

Status of Wave and Tidal Power Technologies for the United States  

SciTech Connect (OSTI)

This paper presents the status of marine applications for renewable energy as of 2008 from a U.S. perspective. Technologies examined include wave, tidal, and ocean current energy extraction devices.

Musial, W.

2008-08-01T23:59:59.000Z

371

Effects of Tidal Turbine Noise on Fish Task 2.1.3.2: Effects on Aquatic Organisms: Acoustics/Noise - Fiscal Year 2011 - Progress Report - Environmental Effects of Marine and Hydrokinetic Energy  

SciTech Connect (OSTI)

Naturally spawning stocks of Chinook salmon (Oncorhynchus tshawytscha) that utilize Puget Sound are listed as threatened (http://www.nwr.noaa.gov/ESA-Salmon-Listings/Salmon-Populations/ Chinook/CKPUG.cfm). Plans exist for prototype tidal turbines to be deployed into their habitat. Noise is known to affect fish in many ways, such as causing a threshold shift in auditory sensitivity or tissue damage. The characteristics of noise, its spectra and level, are important factors that influence the potential for the noise to injure fish. For example, the frequency range of the tidal turbine noise includes the audiogram (frequency range of hearing) of most fish. This study (Effects on Aquatic Organisms, Subtask 2.1.3.2: Acoustics) was performed during FY 2011 to determine if noise generated by a 6-m-diameter open-hydro turbine might affect juvenile Chinook salmon hearing or cause barotrauma. After they were exposed to simulated tidal turbine noise, the hearing of juvenile Chinook salmon was measured and necropsies performed to check for tissue damage. Experimental groups were (1) noise exposed, (2) control (the same handling as treatment fish but without exposure to tidal turbine noise), and (3) baseline (never handled). Preliminary results indicate that low levels of tissue damage may have occurred but that there were no effects of noise exposure on the auditory systems of the test fish.

Halvorsen, Michele B.; Carlson, Thomas J.; Copping, Andrea E.

2011-09-30T23:59:59.000Z

372

Development of a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI)  

SciTech Connect (OSTI)

Satellite-observed radiance is a nonlinear functional of surface properties and atmospheric temperature and absorbing gas profiles as described by the radiative transfer equation (RTE). In the era of hyperspectral sounders with thousands of high-resolution channels, the computation of the radiative transfer model becomes more time-consuming. The radiative transfer model performance in operational numerical weather prediction systems still limits the number of channels we can use in hyperspectral sounders to only a few hundreds. To take the full advantage of such high-resolution infrared observations, a computationally efficient radiative transfer model is needed to facilitate satellite data assimilation. In recent years the programmable commodity graphics processing unit (GPU) has evolved into a highly parallel, multi-threaded, many-core processor with tremendous computational speed and very high memory bandwidth. The radiative transfer model is very suitable for the GPU implementation to take advantage of the hardware's efficiency and parallelism where radiances of many channels can be calculated in parallel in GPUs. In this paper, we develop a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI) launched in 2006 onboard the first European meteorological polar-orbiting satellites, METOP-A. Each IASI spectrum has 8461 spectral channels. The IASI radiative transfer model consists of three modules. The first module for computing the regression predictors takes less than 0.004% of CPU time, while the second module for transmittance computation and the third module for radiance computation take approximately 92.5% and 7.5%, respectively. Our GPU-based IASI radiative transfer model is developed to run on a low-cost personal supercomputer with four GPUs with total 960 compute cores, delivering near 4 TFlops theoretical peak performance. By massively parallelizing the second and third modules, we reached 364x speedup for 1 GPU and 1455x speedup for all 4 GPUs, both with respect to the original CPU-based single-threaded Fortran code with the -O{sub 2} compiling optimization. The significant 1455x speedup using a computer with four GPUs means that the proposed GPU-based high-performance forward model is able to compute one day's amount of 1,296,000 IASI spectra within nearly 10 min, whereas the original single CPU-based version will impractically take more than 10 days. This model runs over 80% of the theoretical memory bandwidth with asynchronous data transfer. A novel CPU-GPU pipeline implementation of the IASI radiative transfer model is proposed. The GPU-based high-performance IASI radiative transfer model is suitable for the assimilation of the IASI radiance observations into the operational numerical weather forecast model.

Huang Bormin, E-mail: bormin@ssec.wisc.ed [Space Science and Engineering Center, University of Wisconsin, Madison (United States); Mielikainen, Jarno [Department of Computer Science, University of Eastern Finland, Kuopio (Finland); Oh, Hyunjong; Allen Huang, Hung-Lung [Space Science and Engineering Center, University of Wisconsin, Madison (United States)

2011-03-20T23:59:59.000Z

373

Hydraulic properties of an artificial tidal inlet through a Texas barrier beach  

E-Print Network [OSTI]

. These littoral barriers are depositional structures continually changed by waves, tidal currents, and winds. Often the only connections between the open ocean and the bays are small restricted channels through the barrier beaches. These chan- nels, or tidal... too large on wide barrier beaches to permit sufficient scour. Breakthroughs also have been found to be caused by gradual buildups of water in the bays, followed by wind shifts to an off. ? shore direction (27). This tends to be supported by Price...

Prather, Stanley Harold

1972-01-01T23:59:59.000Z

374

A Multi-Methods Approach to HRA and Human Performance Modeling: A Field Assessment  

SciTech Connect (OSTI)

The Advanced Test Reactor (ATR) is a research reactor at the Idaho National Laboratory is primarily designed and used to test materials to be used in other, larger-scale and prototype reactors. The reactor offers various specialized systems and allows certain experiments to be run at their own temperature and pressure. The ATR Canal temporarily stores completed experiments and used fuel. It also has facilities to conduct underwater operations such as experiment examination or removal. In reviewing the ATR safety basis, a number of concerns were identified involving the ATR canal. A brief study identified ergonomic issues involving the manual handling of fuel elements in the canal that may increase the probability of human error and possible unwanted acute physical outcomes to the operator. In response to this concern, that refined the previous HRA scoping analysis by determining the probability of the inadvertent exposure of a fuel element to the air during fuel movement and inspection was conducted. The HRA analysis employed the SPAR-H method and was supplemented by information gained from a detailed analysis of the fuel inspection and transfer tasks. This latter analysis included ergonomics, work cycles, task duration, and workload imposed by tool and workplace characteristics, personal protective clothing, and operational practices that have the potential to increase physical and mental workload. Part of this analysis consisted of NASA-TLX analyses, combined with operational sequence analysis, computational human performance analysis (CHPA), and 3D graphical modeling to determine task failures and precursors to such failures that have safety implications. Experience in applying multiple analysis techniques in support of HRA methods is discussed.

Jacques Hugo; David I Gertman

2012-06-01T23:59:59.000Z

375

Recommended Method To Account For Daughter Ingrowth For The Portsmouth On-Site Waste Disposal Facility Performance Assessment Modeling  

SciTech Connect (OSTI)

A 3-D STOMP model has been developed for the Portsmouth On-Site Waste Disposal Facility (OSWDF) at Site D as outlined in Appendix K of FBP 2013. This model projects the flow and transport of the following radionuclides to various points of assessments: Tc-99, U-234, U-235, U-236, U-238, Am-241, Np-237, Pu-238, Pu-239, Pu-240, Th-228, and Th-230. The model includes the radioactive decay of these parents, but does not include the associated daughter ingrowth because the STOMP model does not have the capability to model daughter ingrowth. The Savannah River National Laboratory (SRNL) provides herein a recommended method to account for daughter ingrowth in association with the Portsmouth OSWDF Performance Assessment (PA) modeling.

Phifer, Mark A.; Smith, Frank G. III

2013-06-21T23:59:59.000Z

376

Gravitational self-force corrections to two-body tidal interactions and the effective one-body formalism  

E-Print Network [OSTI]

Tidal interactions have a significant influence on the late dynamics of compact binary systems, which constitute the prime targets of the upcoming network of gravitational-wave detectors. We refine the theoretical description of tidal interactions (hitherto known only to the second post-Newtonian level) by extending our recently developed analytic self-force formalism, for extreme mass-ratio binary systems, to the computation of several tidal invariants. Specifically, we compute, to linear order in the mass ratio and to the 7.5$^{\\rm th}$ post-Newtonian order, the following tidal invariants: the square and the cube of the gravitoelectric quadrupolar tidal tensor, the square of the gravitomagnetic quadrupolar tidal tensor, and the square of the gravitoelectric octupolar tidal tensor. Our high-accuracy analytic results are compared to recent numerical self-force tidal data by Dolan et al. \\cite{Dolan:2014pja}, and, notably, provide an analytic understanding of the light ring asymptotic behavior found by them. We transcribe our kinematical tidal-invariant results in the more dynamically significant effective one-body description of the tidal interaction energy. By combining, in a synergetic manner, analytical and numerical results, we provide simple, accurate analytic representations of the global, strong-field behavior of the gravitoelectric quadrupolar tidal factor. A striking finding is that the linear-in-mass-ratio piece in the latter tidal factor changes sign in the strong-field domain, to become negative (while its previously known second post-Newtonian approximant was always positive). We, however, argue that this will be more than compensated by a probable fast growth, in the strong-field domain, of the nonlinear-in-mass-ratio contributions in the tidal factor.

Donato Bini; Thibault Damour

2014-09-24T23:59:59.000Z

377

Models for source term, flow, transport and dose assessment in NRC`s Iterative Performance Assessment, Phase 2  

SciTech Connect (OSTI)

The core consequence modules for the recently completed Phase 2 Iterative Performance Assessment (IPA) of the Yucca Mountain repository for high-level nuclear waste depend on models for releases from the engineered barrier system (source term), flow of liquid and gas, transport of radionuclides in the geosphere and assessment of dose to target populations. The source term model includes temperature and moisture phenomena in the near-field environment, general, pitting and crevice corrosion, contact of the waste form by water, dissolution and oxidation of the waste form, and transport of dissolved and gaseous radionuclides from the waste package by advection and diffusion. The liquid flow and transport models describe water flow through fractures and matrix in both the unsaturated and saturated zones. Models for flow of gas and transport of {sup 14}CO{sub 2} released from the engineered barrier system to the atmosphere take into account repository heat and the geothermal gradient. The dose assessment model calculates doses to a regional population and a farm family for an assumed reference biosphere in the vicinity of the repository. The Phase 2 IPA led to a number of suggestions for model improvement: (1) improve the ability of the models to include spatial and temporal variability in the parameters; (2) improve the coupling among processes, especially the effects of changing environments in the waste packages; (3) develop more mechanistic models, but abstracted for use in total system performance assessment; and (4) use more site specific parameters, especially for the dose assessments.

McCartin, T.; Codell, R.; Neel, R.; Ford, W.; Wescott, R.; Bradbury, J. [Nuclear Regulatory Commission, Washington, DC (United States); Sagar, B.; Walton, J. [Center for Nuclear Waste Regulatory Analyses, San Antonio, TX (United States)

1994-12-31T23:59:59.000Z

378

Model-driven Memory Optimizations for High Performance Computing: From Caches to I/o.  

E-Print Network [OSTI]

??High performance systems are quickly evolving to keep pace with application demands, and we observe greater complexity in system design at all scales. Parallelism, in… (more)

Frasca, Michael

2012-01-01T23:59:59.000Z

379

E-Print Network 3.0 - array performance model Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ON APPLIED SUPERCONDUCTIVITY, VOL. 16, NO. 4, DECEMBER 2006 2005 Arrays of SNS Josephson Junctions Summary: array and to optimize their performance for Josephson voltage...

380

Model-Based Functional Performance Testing of AHU in Kista Entre  

E-Print Network [OSTI]

A seasonal functional performance test based on detailed system simulation together with intensive trending is used to commission a large AHU in the office building, Kista Entré, Sweden....

Carling, P.; Isakson, P.

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Performance-degradation model for Li4Ti5O12-based battery cells used in wind power applications  

E-Print Network [OSTI]

1 Performance-degradation model for Li4Ti5O12-based battery cells used in wind power applications D the negative impact of wind power grid integration on the power system stability, which is caused. INTRODUCTION Future wind power plants (WPPs) are intended to function like todays conventional power plants

Teodorescu, Remus

382

MODELING OF TRIPLE JUNCTION A-SI SOLAR CELLS USING ASA: ANALYSIS OF DEVICE PERFORMANCE UNDER VARIOUS FAILURE SCENARIOS  

E-Print Network [OSTI]

have experienced a significant increase in the recent years. Solar panels with triple- junction found. To assist the optimization of solar cell fabrication and cost-effective industrial photovoltaicMODELING OF TRIPLE JUNCTION A-SI SOLAR CELLS USING ASA: ANALYSIS OF DEVICE PERFORMANCE UNDER

Deng, Xunming

383

SOME ANALYTIC MODELS OF PASSIVE SOLAR BUILDING PERFORMANCE: A THEORETICAL APPROACH TO THE DESIGN OF ENERGY-CONSERVING BUILDINGS  

E-Print Network [OSTI]

PASSIVE SOLAR BUILDING PERFORMANCE: A THEORETICAL APPROACH TO THE DESIGNpassive solar buildings, and the concommitant inability to predict the results of various designs.Passive solar modelling is worthwhile as a tool for imple- menting one important conservative strategy -- the use of building design

Goldstein, David Baird

2011-01-01T23:59:59.000Z

384

SKA as a powerful hunter of jetted Tidal Disruption Events  

E-Print Network [OSTI]

Observational consequences of the tidal disruption of stars by supermassive black holes (SMBHs) can enable us to discover quiescent SMBHs and constrain their mass function. Moreover, observing jetted TDEs (from previously non-active galaxies) provides us with a new means of studying the early phases of jet formation and evolution in an otherwise "pristine" environment. Although several (tens) TDEs have been discovered since 1999, only two jetted TDEs have been recently discovered in hard X-rays, and only one, Swift J1644+57, has a precise localization which further supports the TDE interpretation. These events alone are not sufficient to address those science issues, which require a substantial increase of the current sample. Despite the way they were discovered, the highest discovery potential for {\\em jetted} TDEs is not held by current and up-coming X-ray instruments, which will yield only a few to a few tens events per year. In fact, the best strategy is to use the Square Kilometer Array to detect TDEs an...

Donnarumma, I; Fender, R; Komossa, S; Paragi, Z; Van Velzen, S; Prandoni, I

2015-01-01T23:59:59.000Z

385

"Circularization" vs. Accretion -- What Powers Tidal Disruption Events?  

E-Print Network [OSTI]

A tidal disruption event (TDE) takes place when a star passes near enough to a massive black hole to be disrupted. About half the star's matter is given elliptical trajectories with large apocenter distances, the other half is unbound. To "circularize", i.e., to form an accretion flow, the bound matter must lose a significant amount of energy, with the actual amount depending on the characteristic scale of the flow measured in units of the black hole's gravitational radius (~ 10^{51} (R/1000R_g)^{-1} erg). Recent numerical simulations (Shiokawa et al., 2015) have revealed that the circularization scale is close to the scale of the most-bound initial orbits, ~ 10^3 M_{BH,6.5}^{-2/3} R_g ~ 10^{15} M_{BH,6.5}^{1/3} cm from the black hole, and the corresponding circularization energy dissipation rate is $\\sim 10^{44} M_{BH,6.5}^{-1/6}$~erg/s. We suggest that the energy liberated during circularization, rather then energy liberated by accretion onto the black hole, powers the observed optical TDE candidates (e.g.A...

Piran, Tsvi; Krolik, Julian; Cheng, Roseanne M; Shiokawa, Hotaka

2015-01-01T23:59:59.000Z

386

A biomathematical model of the restoring effects of caffeine on cognitive performance during sleep deprivation  

E-Print Network [OSTI]

Squared Error n Correspondence to: DoD Biotechnology High Performance Computing Soft- ware Applications , Gary H. Kamimori b , Thomas J. Balkin b , Jaques Reifman a,n a DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army

387

The influence of team mental models and team planning on team performance  

E-Print Network [OSTI]

approaches on post-planning MM similarity. Third, I examined the influence of post-planning teamwork and taskwork MM similarity on team performance. I tested these relationships with 172 three-person ad hoc teams performing a problem-solving execution task...

Leiva Neuenschwander, Pedro Ignacio

2009-06-02T23:59:59.000Z

388

Indirect Performance Sensing for On-Chip Analog Self-Healing via Bayesian Model Fusion  

E-Print Network [OSTI]

, B. Parker2 , A. Valdes-Garcia2 , M. Sanduleanu2 , J. Tierno2 , D. Friedman2 1 Electrical & Computer. Wang1 , S. Yaldiz1 , X. Li1 , L. Pileggi1 , A. Natarajan2,3 , M. Ferriss2 , J. Plouchart2 , B. Sadhu2 a set of other performance metrics, referred to as the performances of measurement (PoM

Li, Xin

389

Sensitivity of economic performance of the nuclear fuel cycle to simulation modeling assumptions  

E-Print Network [OSTI]

Comparing different nuclear fuel cycles and assessing their implications require a fuel cycle simulation model as complete and realistic as possible. In this thesis, methodological implications of modeling choices are ...

Bonnet, Nicéphore

2007-01-01T23:59:59.000Z

390

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007 Annual Report.  

SciTech Connect (OSTI)

This document is the first annual report for the study titled 'Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River'. Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council's Columbia Basin Fish and Wildlife Program. The goal of the 2007-2009 Tidal Freshwater Monitoring Study is to answer the following questions: In what types of habitats within the tidal freshwater area of the lower Columbia River and estuary (LCRE; Figure 1) are yearling and subyearling salmonids found, when are they present, and under what environmental conditions?1 And, what is the ecological importance2 of shallow (0-5 m) tidal freshwater habitats to the recovery of Upper Columbia River spring Chinook salmon and steelhead and Snake River fall Chinook salmon? Research in 2007 focused mainly on the first question, with fish stock identification data providing some indication of Chinook salmon presence at the variety of habitat types sampled. The objectives and sub-objectives for the 2007 study were as follows: (1) Habitat and Fish Community Characteristics-Provide basic data on habitat and fish community characteristics for yearling and subyearling salmonids at selected sites in the tidal freshwater reach in the vicinity of the Sandy River delta. (1a) Characterize vegetation assemblage percent cover, conventional water quality, substrate composition, and beach slope at each of six sampling sites in various tidal freshwater habitat types. (1b) Determine fish community characteristics, including species composition, abundance, and temporal and spatial distributions. (1c) Estimate the stock of origin for the yearling and subyearling Chinook salmon captured at the sampling sites using genetic analysis. (1d) Statistically assess the relationship between salmonid abundance and habitat parameters, including ancillary variables such as temperature and river stage. (2) Acoustic Telemetry Monitoring-Assess feasibility of applying Juvenile Salmon Acoustic Telemetry System (JSATS) technology to determine migration characteristics from upriver of Bonneville Dam through the study area (vicinity of the Sandy River delta/Washougal River confluence). (2a) Determine species composition, release locations, and distributions of JSATS-tagged fish. (2b) Estimate run timing, residence times, and migration pathways for these fish. Additionally, both objectives serve the purpose of baseline research for a potential tidal rechannelization project on the Sandy River. The U.S. Forest Service, in partnership with the Bonneville Power Administration and the U.S. Army Corps of Engineers, is currently pursuing reconnection of the east (relict) Sandy River channel with the current channel to improve fish and wildlife habitat in the Sandy River delta. Our study design and the location of sampling sites in this reach provide baseline data to evaluate the potential restoration.

Sobocinski, Kathryn; Johnson, Gary; Sather, Nichole [Pacific Northwest National Laboratory

2008-03-17T23:59:59.000Z

391

NINTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE  

SciTech Connect (OSTI)

A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. One approach has been to periodically evaluate the leak performance of O-rings being aged in mock-up 9975 Primary Containment Vessels (PCVs) at elevated temperatures. Other methods such as compression-stress relaxation (CSR) tests and field surveillance are also on-going to evaluate O-ring behavior. Seventy tests using PCV mock-ups were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they continue to meet the leak-tightness criterion defined in ANSI standard N14.5-97. Due to material substitution, fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The earliest 300 °F GLT O-ring fixture failure was observed at 34 months. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 72 - 96 months, which bounds O-ring temperatures anticipated during storage in K-Area Complex (KAC). Based on expectations that the 200 ºF fixtures will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures, thus providing additional time to failure data. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 ºF. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 ºF for 54 - 57 months. No additional O-ring failures have been observed since the last interim report was issued. Aging and periodic leak testing will continue for the remaining PCV fixtures. Additional irradiation of several fixtures is recommended to maintain a balance between thermal and radiation exposures similar to that experienced in storage, and to show the degree of consistency of radiation response between GLT and GLT-S O-rings.

Daugherty, W.

2014-08-06T23:59:59.000Z

392

Commercial Building Energy Baseline Modeling Software: Performance Metrics and Method Testing with Open Source Models and Implications for Proprietary Software Testing  

SciTech Connect (OSTI)

The overarching goal of this work is to advance the capabilities of technology evaluators in evaluating the building-level baseline modeling capabilities of Energy Management and Information System (EMIS) software. Through their customer engagement platforms and products, EMIS software products have the potential to produce whole-building energy savings through multiple strategies: building system operation improvements, equipment efficiency upgrades and replacements, and inducement of behavioral change among the occupants and operations personnel. Some offerings may also automate the quantification of whole-building energy savings, relative to a baseline period, using empirical models that relate energy consumption to key influencing parameters, such as ambient weather conditions and building operation schedule. These automated baseline models can be used to streamline the whole-building measurement and verification (M&V) process, and therefore are of critical importance in the context of multi-measure whole-building focused utility efficiency programs. This report documents the findings of a study that was conducted to begin answering critical questions regarding quantification of savings at the whole-building level, and the use of automated and commercial software tools. To evaluate the modeling capabilities of EMIS software particular to the use case of whole-building savings estimation, four research questions were addressed: 1. What is a general methodology that can be used to evaluate baseline model performance, both in terms of a) overall robustness, and b) relative to other models? 2. How can that general methodology be applied to evaluate proprietary models that are embedded in commercial EMIS tools? How might one handle practical issues associated with data security, intellectual property, appropriate testing ‘blinds’, and large data sets? 3. How can buildings be pre-screened to identify those that are the most model-predictable, and therefore those whose savings can be calculated with least error? 4. What is the state of public domain models, that is, how well do they perform, and what are the associated implications for whole-building measurement and verification (M&V)? Additional project objectives that were addressed as part of this study include: (1) clarification of the use cases and conditions for baseline modeling performance metrics, benchmarks and evaluation criteria, (2) providing guidance for determining customer suitability for baseline modeling, (3) describing the portfolio level effects of baseline model estimation errors, (4) informing PG&E’s development of EMIS technology product specifications, and (5) providing the analytical foundation for future studies about baseline modeling and saving effects of EMIS technologies. A final objective of this project was to demonstrate the application of the methodology, performance metrics, and test protocols with participating EMIS product vendors.

Price, Phillip N.; Granderson, Jessica; Sohn, Michael; Addy, Nathan; Jump, David

2013-09-01T23:59:59.000Z

393

EIGHTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE  

SciTech Connect (OSTI)

A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 61 - 85 months, which is still bounding to O-ring temperatures during storage in KArea Complex (KAC). Based on expectations that the fixtures aging at 200 ºF will remain leaktight for a significant period yet to come, 2 additional fixtures began aging in 2011 at an intermediate temperature of 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 ºF. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 ºF for 41 - 45 months. Aging and periodic leak testing will continue for the remaining PCV fixtures.

Daugherty, W. L.

2013-09-03T23:59:59.000Z

394

Estuarine Habitats for Juvenile Salmon in the Tidally-Influenced Lower Columbia River and Estuary : Reporting Period September 15, 2008 through May 31, 2009.  

SciTech Connect (OSTI)

This work focuses on the numerical modeling of Columbia River estuarine circulation and associated modeling-supported analyses conducted as an integral part of a multi-disciplinary and multi-institutional effort led by NOAA's Northwest Fisheries Science Center. The overall effort is aimed at: (1) retrospective analyses to reconstruct historic bathymetric features and assess effects of climate and river flow on the extent and distribution of shallow water, wetland and tidal-floodplain habitats; (2) computer simulations using a 3-dimensional numerical model to evaluate the sensitivity of salmon rearing opportunities to various historical modifications affecting the estuary (including channel changes, flow regulation, and diking of tidal wetlands and floodplains); (3) observational studies of present and historic food web sources supporting selected life histories of juvenile salmon as determined by stable isotope, microchemistry, and parasitology techniques; and (4) experimental studies in Grays River in collaboration with Columbia River Estuary Study Taskforce (CREST) and the Columbia Land Trust (CLT) to assess effects of multiple tidal wetland restoration projects on various life histories of juvenile salmon and to compare responses to observed habitat-use patterns in the mainstem estuary. From the above observations, experiments, and additional modeling simulations, the effort will also (5) examine effects of alternative flow-management and habitat-restoration scenarios on habitat opportunity and the estuary's productive capacity for juvenile salmon. The underlying modeling system is part of the SATURN1coastal-margin observatory [1]. SATURN relies on 3D numerical models [2, 3] to systematically simulate and understand baroclinic circulation in the Columbia River estuary-plume-shelf system [4-7] (Fig. 1). Multi-year simulation databases of circulation are produced as an integral part of SATURN, and have multiple applications in understanding estuary/plume variability, the role of the estuary and plume on salmon survival, and functional changes in the estuary-plume system in response to climate and human activities.

Baptista, António M. [Oregon Health & Science University, Science and Technology Center for Coastal Margin Observation and Prediction

2009-08-02T23:59:59.000Z

395

Evaluation of Blade-Strike Models for Estimating the Biological Performance of Kaplan Turbines  

SciTech Connect (OSTI)

Bio-indexing of hydroturbines is an important means to optimize passage conditions for fish by identifying operations for existing and new design turbines that minimize the probability of injury. Cost-effective implementation of bio-indexing requires the use of tools such as numerical and physical turbine models to generate hypotheses for turbine operations that can be tested at prototype scales using live fish. Numerical deterministic and stochastic blade strike models were developed for a 1:25-scale physical turbine model built by the U.S. Army Corps of Engineers for the original design turbine at McNary Dam and for prototype-scale original design and replacement minimum gap runner (MGR) turbines at Bonneville Dam's first powerhouse. Blade strike probabilities predicted by both models were comparable with the overall trends in blade strike probability observed in both prototype-scale live fish survival studies and physical turbine model using neutrally buoyant beads. The predictions from the stochastic model were closer to the experimental data than the predictions from the deterministic model because the stochastic model included more realistic consideration of the aspect of fish approaching to the leading edges of turbine runner blades. Therefore, the stochastic model should be the preferred method for the prediction of blade strike and injury probability for juvenile salmon and steelhead using numerical blade-strike models.

Deng, Zhiqun; Carlson, Thomas J.; Ploskey, Gene R.; Richmond, Marshall C.; Dauble, Dennis D.

2007-11-10T23:59:59.000Z

396

System dynamics modeling for human performance in nuclear power plant operation  

E-Print Network [OSTI]

Perfect plant operation with high safety and economic performance is based on both good physical design and successful organization. However, in comparison with the affection that has been paid to technology research, the ...

Chu, Xinyuan

2006-01-01T23:59:59.000Z

397

nine sites. A model study was performed by sequential hydrolysis of purified as1-  

E-Print Network [OSTI]

) the individual aromatic amino acid composition of the peptides using reversed-phase high-performance liq- uid- matography or electrodialysis. We demonstrated that the residual phenylalanine level in the peptidic fraction

Paris-Sud XI, Université de

398

Program listing for heat-pump seasonal-performance model (SPM). [CNHSPM  

SciTech Connect (OSTI)

The computer program CNHSPM is listed which predicts heat pump seasonal energy consumption (including defrost, cyclic degradation, and supplementary heat) using steady state rating point performance and binned weather data. (LEW)

Not Available

1982-06-30T23:59:59.000Z

399

Experimental testing and modelling of a passive mechanical steering compensator for high-performance motorcycles  

E-Print Network [OSTI]

-performance motorcycles Christakis Papageorgiou, Oliver G. Lockwood, Neil E. Houghton and Malcolm C. Smith Abstract of the method to the control of motorcycles steer- ing instabilities. Simulation studies have shown

Cambridge, University of

400

Influence of two dynamic predictive clothing insulation models on building energy performance  

E-Print Network [OSTI]

Predictive Clothing Insulation Models on Building Energyunnecessarily higher clothing insulation and lower heatingthat the constant clothing insulation assumption lead to the

Lee, Kwang Ho; Schiavon, Stefano

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Development of a High-Performance Office Building Simulation Model for a Hot and Humid Climate  

E-Print Network [OSTI]

48% total energy savings above the ASHRAE 90.1-1999 code and 61% savings when compared to the calibrated simulation model of the case-study building. The results show that substantial energy savings can be achieved only by using common... to the field measured data and was presented in the previous publication (Cho and Haberl, 2008a). The calibrated simulation model was further extended to an ASHRAE 90.1 code-compliant model, which was used as the baseline model for the development of a...

Cho, S.; Haberl, J.

402

Seismic Performance, Modeling, and Failure Assessment of Reinforced Concrete Shear Wall Buildings  

E-Print Network [OSTI]

J.W. , (2009). Testing and Reinforced Concrete Coupling2010). "Testing and Modeling of Reinforced Concrete Couplingscale testing of four-story reinforced concrete and post-

Tuna, Zeynep

2012-01-01T23:59:59.000Z

403

An Evidence-Based Evaluation of the Cumulative Effects of Tidal Freshwater and Estuarine Ecosystem Restoration on Endangered Juvenile Salmon in the Columbia River: Final Report  

SciTech Connect (OSTI)

The listing of 13 salmon and steelhead stocks in the Columbia River basin (hereafter collectively referred to as “salmon”) under the Endangered Species Act of 1973, as amended, has stimulated tidal wetland restoration in the lower 235 kilometers of the Columbia River and estuary for juvenile salmon habitat functions. The purpose of the research reported herein was to evaluate the effect on listed salmon of the restoration effort currently being conducted under the auspices of the federal Columbia Estuary Ecosystem Restoration Program (CEERP). Linking changes in the quality and landscape pattern of tidal wetlands in the lower Columbia River and estuary (LCRE) to salmon recovery is a complex problem because of the characteristics of the ecosystem, the salmon, the restoration actions, and available sampling technologies. Therefore, we designed an evidence-based approach to develop, synthesize, and evaluate information to determine early-stage (~10 years) outcomes of the CEERP. We developed an ecosystem conceptual model and from that, a primary hypothesis that habitat restoration activities in the LCRE have a cumulative beneficial effect on juvenile salmon. There are two necessary conditions of the hypothesis: • habitat-based indicators of ecosystem controlling factors, processes, and structures show positive effects from restoration actions, and • fish-based indicators of ecosystem processes and functions show positive effects from restoration actions and habitats undergoing restoration. Our evidence-based approach to evaluate the primary hypothesis incorporated seven lines of evidence, most of which are drawn from the LCRE. The lines of evidence are spatial and temporal synergies, cumulative net ecosystem improvement, estuary-wide meta-analysis, offsite benefits to juvenile salmon, landscape condition evaluation, and evidence-based scoring of global literature. The general methods we used to develop information for the lines of evidence included field measurements, data analyses, modeling, meta-analysis, and reanalysis of previously collected data sets. We identified a set of 12 ancillary hypotheses regarding habitat and salmon response. Each ancillary hypothesis states that the response metric will trend toward conditions at relatively undisturbed reference sites. We synthesized the evidence for and against the two necessary conditions by using eleven causal criteria: strength, consistency, specificity, temporality, biological gradient, plausibility, coherence, experiment, analogy, complete exposure pathway, and predictive performance. Our final evaluation included cumulative effects assessment because restoration is occurring at multiple sites and the collective effect is important to salmon recovery. We concluded that all five lines of evidence from the LCRE indicated positive habitat-based and fish-based responses to the restoration performed under the CEERP, although tide gate replacements on small sloughs were an exception. Our analyses suggested that hydrologic reconnections restore access for fish to move into a site to find prey produced there. Reconnections also restore the potential for the flux of prey from the site to the main stem river, where our data show that they are consumed by salmon. We infer that LCRE ecosystem restoration supports increased juvenile salmon growth and enhanced fitness (condition), thereby potentially improving survival rates during the early ocean stage.

Diefenderfer, Heida L.; Johnson, Gary E.; Thom, Ronald M.; Borde, Amy B.; Woodley, Christa M.; Weitkamp, Laurie A.; Buenau, Kate E.; Kropp, Roy K.

2013-12-01T23:59:59.000Z

404

A Bulk Tungsten Tile for JET: Derivation of Power-Handling Performance and Validation of the Thermal Model, in the MARION Facility  

E-Print Network [OSTI]

A Bulk Tungsten Tile for JET: Derivation of Power-Handling Performance and Validation of the Thermal Model, in the MARION Facility

405

Simulation of heavy oil reservoir performance using a non-Newtonian flow model  

E-Print Network [OSTI]

. This reduction of viscosity as a function of shear rate has a significant effect on rates and other parameters when simulating reservoir performance. The objective of this study is to compare the simulation results of Newtonian and non-Newtonian oils under...)ected to increasing shear rate, the viscosity decreases. This behavior implies that the oil viscosity varies as a function of not only pressure, but also shear rate. This behavior is important when simulating heavy-oil reservoir performance. To simulate the flow...

Narahara, Gene Masao

1983-01-01T23:59:59.000Z

406

An analytical model and performance data for a cylindrical parabolic collector  

SciTech Connect (OSTI)

Concentrating solar collectors provide higher fluid temperatures than flat-plate, an important advantage in many applications. The parabolic cylinder is one of the most popular types of concentrating collectors because of its relatively simple construction and tracking configuration. A mathematical model was developed for one such collector in order to predict thermal efficiency as a function of solar insolation. An experiment was then devised in an attempt to verify this model. Discrepancies between predicted and observed values are discussed, and suggestions are made for improving the model and the experimental procedure.

Ford, F.M.; Stewart, W.E.

1980-12-01T23:59:59.000Z

407

General Relativistic Hydrodynamic Simulation of Accretion Flow from a Stellar Tidal Disruption  

E-Print Network [OSTI]

We study how the matter dispersed when a supermassive black hole tidally disrupts a star joins an accretion flow. Combining a relativistic hydrodynamic simulation of the stellar disruption with a relativistic hydrodynamics simulation of the tidal debris motion, we track such a system until ~80% of the stellar mass bound to the black hole has settled into an accretion flow. Shocks near the stellar pericenter and also near the apocenter of the most tightly-bound debris dissipate orbital energy, but only enough to make the characteristic radius comparable to the semi-major axis of the most-bound material, not the tidal radius as previously thought. The outer shocks are caused by post-Newtonian effects, both on the stellar orbit during its disruption and on the tidal forces. Accumulation of mass into the accretion flow is non-monotonic and slow, requiring ~3--10x the orbital period of the most tightly-bound tidal streams, while the inflow time for most of the mass may be comparable to or longer than the mass accu...

Shiokawa, Hotaka; Cheng, Roseanne M; Piran, Tsvi; Noble, Scott C

2015-01-01T23:59:59.000Z

408

Report on High Performance Building's Energy Modeling, Physical Building Information Modeling for Solar Building Design and Simulation  

E-Print Network [OSTI]

This report was created for the National Science Foundation-Physical Building Information Modeling (NSF-PBIM) project. This report describes the analysis of a solar office building using the following software: the legacy tools (DOE 2.1e, the F...

Alcocer, J.; Haberl, J. S.

2012-01-01T23:59:59.000Z

409

Experimental Measurement of a Model Pipeline Dredge Entrance Loss Coefficient and Modification of a Spreadsheet for Estimating Model Dredge Performance  

E-Print Network [OSTI]

for Dredging Studies’ model cutter suction dredge. Testing was completed over the spectrum of specific gravities (SG) and flow rates achievable in the laboratory. The results show that the minor loss coefficient of the screen is a function of specific gravity...

Girani, Joseph

2014-04-17T23:59:59.000Z

410

CPR: Composable Performance Regression for Scalable Multiprocessor Models Benjamin C. Lee  

E-Print Network [OSTI]

utilization cycle by cycle to estimate performance. Multiprocessor simulators, however, must account for synchronization events that in- crease the cost of every cycle simulated and shared resource contention that increases the total number of cycles simulated. These effects cause multiprocessor simulation times to scale

Lee, Benjamin C.

411

SIMULATING THE FEASIBILITY AND PERFORMANCE OF A REALTIME WATER MARKET BY COUPLING AN AGENTBASED MODEL AND  

E-Print Network [OSTI]

without artificial irrigation (bushel/acre) : maximum yield without water shortage(bushel/acre) : maximumSIMULATING THE FEASIBILITY AND PERFORMANCE OF A REALTIME WATER MARKET BY COUPLING AN AGENTBASED Engineering, University of Illinois at Urbana­Champaign Erhu Du1, Barbara Minsker1 and Ximing Cai1, Water

Yang, Zong-Liang

412

A Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performance  

E-Print Network [OSTI]

coeff. with yaw rate CY r Change in sideforce coeff. with yaw rate EA Expected system availability EG as multi-state systems, where a multi-state system is one having a finite set of performance levels be established. Such an approach allows designers to identify those elements that might drive system loss

de Weck, Olivier L.

413

Analysis and Performance Results of a Molecular Modeling Application on Merrimac  

E-Print Network [OSTI]

a large number of functional units, and utilize a deep register hierarchy with high local bandwidth Merrimac's potential to deliver high performance. 1. Introduction Modern semiconductor technology allows us-consumer locality, such as the locality present within a function call, in local register files (LRF) and long term

Dally, William J.

414

Fuzzy Comprehensive Evaluation Model and Influence Factors Analysis on Comprehensive Performance of Green Buildings  

E-Print Network [OSTI]

management. In order to solve problems of subjectivity, uncertainty and impossibility of quantitative analysis when evaluating green building, this study establishes a multi-level fuzzy evaluation model by means of fuzzy mathematics method to analyze...

Sun, J.; Wu, Y.; Dai, Z.; Hao, Y.

2006-01-01T23:59:59.000Z

415

Probabilistic Performance Forecasting for Unconventional Reservoirs With Stretched-Exponential Model  

E-Print Network [OSTI]

a reserves-evaluation workflow that couples the traditional decline-curve analysis with a probabilistic forecasting frame. The stretched-exponential production decline model (SEPD) underpins the production behavior. Our recovery appraisal workflow...

Can, Bunyamin

2011-08-08T23:59:59.000Z

416

Testing Linear Diagnostics of Ensemble Performance on a Simplified Global Circulation Model  

E-Print Network [OSTI]

is inherently flow dependent and that the ensemble predicts potential patterns of forecast errors more reliably than the magnitudes of the errors. A low-resolution global circulation model is implemented to calculate linear diagnostics in the vector space...

Nelson, Ethan

2011-04-21T23:59:59.000Z

417

Evaluation of models for the prediction of fluidized-bed reactor performance  

E-Print Network [OSTI]

models w1th exper 1mental results are presented. Additional results are also presented in the following sections. 43 Jet penetration De th In order to correlate the jet penitration experimental results, several non-dimentional parameters were chosen...

Frederick, John Michael

1980-01-01T23:59:59.000Z

418

A Comparison of Reduced-Form Permit Price Models and their Empirical Performances  

E-Print Network [OSTI]

Equilibrium models have been proposed in literature with the aim of describing the evolution of the price of emission permits. This paper derives _rst estimation methods for the calibration of three competing equilibrium ...

Taschini, Luca

419

Reconfigurable autopilot design for a high performance aircraft using model predictive control  

E-Print Network [OSTI]

The losses of military and civilian aircraft due to control surface failures have prompted research into controllers with a degree of reconfiguration. This thesis will describe a design approach incorporating Model Predictive ...

Ruiz, Jose Pedro, 1980-

2004-01-01T23:59:59.000Z

420

Integration of Feedstock Assembly System and Cellulosic Ethanol Conversion Models to Analyze Bioenergy System Performance  

SciTech Connect (OSTI)

Research barriers continue to exist in all phases of the emerging cellulosic ethanol biorefining industry. These barriers include the identification and development of a sustainable and abundant biomass feedstock, the assembly of viable assembly systems formatting the feedstock and moving it from the field (e.g., the forest) to the biorefinery, and improving conversion technologies. Each of these phases of cellulosic ethanol production are fundamentally connected, but computational tools used to support and inform analysis within each phase remain largely disparate. This paper discusses the integration of a feedstock assembly system modeling toolkit and an Aspen Plus® conversion process model. Many important biomass feedstock characteristics, such as composition, moisture, particle size and distribution, ash content, etc. are impacted and most effectively managed within the assembly system, but generally come at an economic cost. This integration of the assembly system and the conversion process modeling tools will facilitate a seamless investigation of the assembly system conversion process interface. Through the integrated framework, the user can design the assembly system for a particular biorefinery by specifying location, feedstock, equipment, and unit operation specifications. The assembly system modeling toolkit then provides economic valuation, and detailed biomass feedstock composition and formatting information. This data is seamlessly and dynamically used to run the Aspen Plus® conversion process model. The model can then be used to investigate the design of systems for cellulosic ethanol production from field to final product.

Jared M. Abodeely; Douglas S. McCorkle; Kenneth M. Bryden; David J. Muth; Daniel Wendt; Kevin Kenney

2010-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Performance Evaluation of K-DEMO Cable-in-conduit Conductors Using the Florida Electro-Mechanical Cable Model  

SciTech Connect (OSTI)

The United States ITER Project Office (USIPO) is responsible for design of the Toroidal Field (TF) insert coil, which will allow validation of the performance of significant lengths of the conductors to be used in the full scale TF coils in relevant conditions of field, current density and mechanical strain. The Japan Atomic Energy Agency (JAEA) will build the TF insert which will be tested at the Central Solenoid Model Coil (CSMC) Test facility at JAEA, Naka, Japan. Three dimensional mathematical model of TF Insert was created based on the initial design geometry data, and included the following features: orthotropic material properties of superconductor material and insulation; external magnetic field from CSMC, temperature dependent properties of the materials; pre-compression and plastic deformation in lap joint. Major geometrical characteristics of the design were preserved including cable jacket and insulation shape, mandrel outline, and support clamps and spacers. The model is capable of performing coupled structural, thermal, and electromagnetic analysis using ANSYS. Numerical simulations were performed for room temperature conditions; cool down to 4K, and the operating regime with 68kA current at 11.8 Tesla background field. Numerical simulations led to the final design of the coil producing the required strain levels on the cable, while simultaneously satisfying the ITER magnet structural design criteria.

Zhai, Yuhu

2013-07-16T23:59:59.000Z

422

Effect of equation of state on prediction of trickle bed reactor model performance  

E-Print Network [OSTI]

of outlet conversion and a temperature profile. In Order to obtain initial guesses for the nonlinear regression a grid search is performed (Ray, 1982) with the assumption that the relationship between temperature and conversion is linear. The initial.... Wrth the initial guesses for and E and the linear temperature conversion assumption the Marquardt method is used to compute a new E and k . At this point the first iteration is complete. These kinetic parameters are then inputed into the trickle bed...

Netherland, Donald Wayne

1985-01-01T23:59:59.000Z

423

Modeling and Simulation of Long-Term Performance of Near-Surface Barriers  

SciTech Connect (OSTI)

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone's back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier's structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes. Thus, the INEEL started a new project on long-term barrier integrity in April 2002 that aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late, prior to system-level failure). This paper describes our computer simulation approach for better understanding the relationships and dynamics between the various components and management decisions in a cap. The simulation is designed to clarify the complex relationships between the various components within the cap system and the various management practices that affect the barrier performance. We have also conceptualized a time-dependent 3-D simulation with rigorous solution to unsaturated flow physics with complex surface boundary conditions.

Piet, S. J.; Jacobson, J. J.; Martian, P.; Martineau, R.; Soto, R.

2003-02-25T23:59:59.000Z

424

Modeling and Simulation of Long-Term Performance of Near-Surface Barriers  

SciTech Connect (OSTI)

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier’s structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements of the barrier system are regarded as constant, including engineered inputs (e.g., fire management strategy, irrigation, vegetation control), surface ecology (critical to assessment of plant transpiration), capillary break interface, material properties, surface erosion rate, etc. Further, to be conservative, only harmful processes are typically considered. A more holistic examination of both harmful and beneficial processes will provide more realistic pre-service prediction and in-service assessment of performance as well as provide designers a tool to encourage beneficial processes while discouraging harmful processes. Thus, the INEEL started a new project on long-term barrier integrity in April 2002 that aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late, prior to system-level failure). This paper describes our computer simulation approach for better understanding the relationships and dynamics between the various components and management decisions in a cap. The simulation is designed to clarify the complex relationships between the various components within the cap system and the various management practices that affect the barrier performance. We have also conceptualized a time-dependent 3-D simulation with rigorous solution to unsaturated flow physics with complex surface boundary conditions.

Piet, Steven James; Jacobson, Jacob Jordan; Soto, Rafael; Martian, Pete; Martineau, Richard Charles

2003-02-01T23:59:59.000Z

425

PERFORMANCE OF A SPECTRAL ELEMENT ATMOSPHERIC MODEL SEAM ON THE HP EXEMPLAR SPP2000.  

E-Print Network [OSTI]

discretization strategy taken from NCAR's Community Climate Model Version 3 (CCM3) [9]. Spectral elements have avoiding clustering points at the poles. Secondly, by using a local coordinate system within each element Fournier for helpful comments. This work was supported in part by the U.S. Department of Energy; Oce

Baer, Ferdinand

426

Efficient chip-level CMP models are required to predict dielectric planarization performance for arbitrary layouts  

E-Print Network [OSTI]

distributed load. The characteris- tic length of the filter, L, is a model parameter which must be z1 z=0 z dropped to 2/. The filter shape corresponds to the deformation profile of an elastic material under distributed load in a circle of radius L/2. ELLIPTIC WEIGHTING FILTER An Integrated Characterization

Boning, Duane S.

427

Time series analysis of regional climate model performance Jason P. Evans  

E-Print Network [OSTI]

in Kansas, United States, including the First International Satellite Land Surface Climatology Project, both regional and global, has become apparent. Predictions of the energy and water balance to evapotranspiration and fails to close the energy budget. All of the models overestimate runoff and evapotranspiration

Evans, Jason

428

Improved Modeling and Understanding of Diffusion-Media Wettability on Polymer-Electrolyte-Fuel-Cell Performance  

SciTech Connect (OSTI)

A macroscopic-modeling methodology to account for the chemical and structural properties of fuel-cell diffusion media is developed. A previous model is updated to include for the first time the use of experimentally measured capillary pressure -- saturation relationships through the introduction of a Gaussian contact-angle distribution into the property equations. The updated model is used to simulate various limiting-case scenarios of water and gas transport in fuel-cell diffusion media. Analysis of these results demonstrate that interfacial conditions are more important than bulk transport in these layers, where the associated mass-transfer resistance is the result of higher capillary pressures at the boundaries and the steepness of the capillary pressure -- saturation relationship. The model is also used to examine the impact of a microporous layer, showing that it dominates the response of the overall diffusion medium. In addition, its primary mass-transfer-related effect is suggested to be limiting the water-injection sites into the more porous gas-diffusion layer.

Weber, Adam

2010-03-05T23:59:59.000Z

429

Modeling of Supply Chain Risk Under Disruptions with Performance Measurement and Robustness Analysis  

E-Print Network [OSTI]

. The model formulation captures supply- side risk as well as demand-side risk, along with uncertainty supply-side disruption risks, transportation and other cost risks, and demand-side uncertainty within, the focus of research has been on "demand-side" risk, which is related to fluctuations in the demand

Nagurney, Anna

430

Behavioral ESD Protection Modeling to perform System Level ESD Efficient Design  

E-Print Network [OSTI]

) and semi- conductor suppliers, the prediction of ElectroStatic Discharge (ESD) events into design phase goal of the proposed model is that it could be shared by IC suppliers and EMs to ensure that ICs can aggressions of a system. The level of ESD stress required during the system qualification is increasing over

Paris-Sud XI, Université de

431

Devising Face Authentication System and Performance Evaluation Based on Statistical Models  

E-Print Network [OSTI]

, Carnegie Mellon University, {smitra, abrock, fienberg}@stat.cmu.edu 2 ECE Department, Carnegie Mellon like PINs and ID cards. This paper focuses on demonstrating the use of statistical models in devising- cation numbers or PINS) and token-based techniques (ID cards, drivers license) in differentiating between

432

Using Physical Models to Study the Gliding Performance of Extinct Animals  

E-Print Network [OSTI]

is to provide a practical guide for the design of dynamically scaled physical models to study the gliding,1 Dennis Evangelista and Karen Yang Department of Integrative Biology, University of California'' presented at the annual meeting of the Society for Integrative and Comparative Biology, January 3­7, 2011

Koehl, Mimi

433

Tidal hydraulics of San Luis Pass, Texas: a field and numerical investigation  

E-Print Network [OSTI]

TIDAL HYDPAULICS OF SAN LUIS PASS, TEXAS: A FIELD AND VBKRICAL INSTIGATION A Thesis by SCOTT JEROME MORTON Submitted to the Graduate College of Texas A(II University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE August 1980 i&Iajor Subject: Ocean Engineering TIDAL HyDRAULICS OF SAN LUIS PASS, TEXAS: A FIELD AND M&IERICAL INVESTIGATION A Thesis by SCOTI' JEROIIE MORTON Approved as to style and content by: (C?airman of Committee) (Member) /member...

Morton, Scott Jerome

1980-01-01T23:59:59.000Z

434

Accuracy in performance appraisals: a comparison of two rater cognitive process models  

E-Print Network [OSTI]

scripts could not participate in this phase of the experiment. Procedure. The two videotaped lectures were shown to all par- ticipants. After each tape, three 7-point Likert rating scales (with extreme anchors of "very poor" and "very good" ) were... of dimensional schemata and Feldman's (1981) cognit1ve categorization theory. To further explore the role of each in the process of performance appra1sal over time, participants in the present study were presented with two d1fferent videotapes of a lecturing...

Major, Susan Lee Frank

1985-01-01T23:59:59.000Z

435

Performance evaluation of Appalachian wells using a microcomputer gas simulation model  

SciTech Connect (OSTI)

The Appalachian Basin contains very low reservoir pressures (as low as 120 psi). To help solve these problems, a one-dimensional gas simulator has been developed for use on a microcomputer. The simulation program provides production engineers with tools to generate data and determine the inflow performance relationships (IPR) of Appalachian-type wells. These Appalachian well field case studies were conducted, whereby various production methods were analyzed using the Nodal analysis method. Consequently, improved design criteria were established for selecting compatible production methods and handling production problems in the Appalachian Basin.

Yu, J.P.; Mustafa, A. (West Virginia Univ., Morgantown (USA)); Hefner, M.H. (CNG Transmission Co., Clarksburg, WV (USA))

1990-04-01T23:59:59.000Z

436

Modeling the Performance of Engineered Systems for Closure and Near-Surface Disposal  

Office of Environmental Management (EM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of Energy Power.pdf11-161-LNG |September 15, 2010 Printing and Mail Managersfor 12of performance cleanup

437

Nuclear Energy Advanced Modeling and Simulation (NEAMS) Waste Integrated Performance and Safety Codes (IPSC) : FY10 development and integration.  

SciTech Connect (OSTI)

This report describes the progress in fiscal year 2010 in developing the Waste Integrated Performance and Safety Codes (IPSC) in support of the U.S. Department of Energy (DOE) Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign. The goal of the Waste IPSC is to develop an integrated suite of computational modeling and simulation capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive waste storage or disposal system. The Waste IPSC will provide this simulation capability (1) for a range of disposal concepts, waste form types, engineered repository designs, and geologic settings, (2) for a range of time scales and distances, (3) with appropriate consideration of the inherent uncertainties, and (4) in accordance with robust verification, validation, and software quality requirements. Waste IPSC activities in fiscal year 2010 focused on specifying a challenge problem to demonstrate proof of concept, developing a verification and validation plan, and performing an initial gap analyses to identify candidate codes and tools to support the development and integration of the Waste IPSC. The current Waste IPSC strategy is to acquire and integrate the necessary Waste IPSC capabilities wherever feasible, and develop only those capabilities that cannot be acquired or suitably integrated, verified, or validated. This year-end progress report documents the FY10 status of acquisition, development, and integration of thermal-hydrologic-chemical-mechanical (THCM) code capabilities, frameworks, and enabling tools and infrastructure.

Criscenti, Louise Jacqueline; Sassani, David Carl; Arguello, Jose Guadalupe, Jr.; Dewers, Thomas A.; Bouchard, Julie F.; Edwards, Harold Carter; Freeze, Geoffrey A.; Wang, Yifeng; Schultz, Peter Andrew

2011-02-01T23:59:59.000Z

438

Use of the WECC WAMS in Wide Area Probing Tests for Validation of System Performance & Modeling  

SciTech Connect (OSTI)

During 2005 and 2006 the Western Electricity Coordinating Council (WECC) performed three major tests of western system dynamics. These tests used a Wide Area Measurement System (WAMS) based primarily on Phasor Measurement Units (PMUs) to determine response to events including the insertion of the 1400-MW Chief Joseph braking resistor, probing signals, and ambient events. Test security was reinforced through real-time analysis of wide area effects, and high-quality data provided dynamic profiles for interarea modes across the entire western interconnection. The tests established that low-level optimized pseudo-random ±20-MW probing with the Pacific DC Intertie (PDCI) roughly doubles the apparent noise that is natural to the power system, providing sharp dynamic information with negligible interference to system operations. Such probing is an effective alternative to use of the 1400-MW Chief Joseph dynamic brake, and it is under consideration as a standard means for assessing dynamic security.

Hauer, John F.; Mittelstadt, William; Martin, Kenneth E.; Burns, J. W.; Lee, Harry; Pierre, John W.; Trudnowski, Daniel

2009-02-01T23:59:59.000Z

439

Performance evaluation of three infiltration models under a surge flow irrigation regime  

E-Print Network [OSTI]

PFM model for Everett irrigation 3/ plot 3/ wheeled row 3. . Actual inflow hydrograph for file ET112 with duty cycle equal to 0. 5 for all surges. 73 29 Proposed inflow hydrograph for file ET112 with duty cycle equal to 0. 5 for the first three... irrigation 2, plot 3, and row 2 at the Everett site. The following information is contained in each spreadsheet file: surge valve-on and -off times for each surge, target and actual inflow rates for each surge, inflow/outflow volumes for each surge...

Benham, Brian Leslie

1990-01-01T23:59:59.000Z

440

Summary Results for Brine Migration Modeling Performed by LANL, LBNL and  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from the GridwiseSiteDepartmentChallenge | DepartmentEnergy Audit ModelSueLetterofSNL

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Impact of Pilot Light Modeling on the Predicted Annual Performance of Residential Gas Water Heaters: Preprint  

SciTech Connect (OSTI)

Modeling residential water heaters with dynamic simulation models can provide accurate estimates of their annual energy consumption, if the units? characteristics and use conditions are known. Most gas storage water heaters (GSWHs) include a standing pilot light. It is generally assumed that the pilot light energy will help make up standby losses and have no impact on the predicted annual energy consumption. However, that is not always the case. The gas input rate and conversion efficiency of a pilot light for a GSWH were determined from laboratory data. The data were used in simulations of a typical GSWH with and without a pilot light, for two cases: 1) the GSWH is used alone; and 2) the GSWH is the second tank in a solar water heating (SWH) system. The sensitivity of wasted pilot light energy to annual hot water use, climate, and installation location was examined. The GSWH used alone in unconditioned space in a hot climate had a slight increase in energy consumption. The GSWH with a pilot light used as a backup to an SWH used up to 80% more auxiliary energy than one without in hot, sunny locations, from increased tank losses.

Maguire, J.; Burch, J.

2013-08-01T23:59:59.000Z

442

Experimental Test Plan DOE Tidal and River Reference Turbines  

SciTech Connect (OSTI)

Our aim is to provide details of the experimental test plan for scaled model studies in St. Anthony Falls Laboratory (SAFL) Main Channel at the University of Minnesota, including a review of study objectives, descriptions of the turbine models, the experimental set-up, instrumentation details, instrument measurement uncertainty, anticipated experimental test cases, post-processing methods, and data archiving for model developers.

Neary, Vincent S [ORNL; Hill, Craig [St. Anthony Falls Laboratory, 2 Third Avenue SE, Minneapolis, MN 55414; Chamorro, Leonardo [St. Anthony Falls Laboratory, 2 Third Avenue SE, Minneapolis, MN 55414; Gunawan, Budi [ORNL

2012-09-01T23:59:59.000Z

443

CRC fuel rating program: road octane performance of oxygenates in 1982 model cars  

SciTech Connect (OSTI)

Because of the widespread interest in the use of alcohols and ethers as gasoline blending components, this program was conducted to evaluate the effects of several oxygenates on gasoline octane performance and to evaluate the effects of car design features such as engine and transmission type. Five oxygenates were evaluated at two nominal concentrations, 5 and 10 volume%, at both regular- and premium-grade octane levels: methanol (MeOH), ethanol (ETOH), isopropanol (IPA), tertiary butanol (TBA), and methyl tertiary butyl ether (MTBE). A blend of 5% MeOH and 5 percent TBA was also tested at both octane levels. Twenty-eight unleaded fuels, including four hydrocarbon fuels, two hydrocarbon fuels plus toluene, and twenty-two oxygenated fuels, were rated in duplicate in thirty-eight cars using the Modified Uniontown Technique (CRC Designation F-28-75 described in Appendix C), plus some additional instructions. All testing was done on chassis dynamometers. Ratings were obtained at full throttle with all thirty-eight cars, and at the most critical part-throttle condition (occurring with manifold vacuum of 4 in. Hg (13.5 kPa) or greater above the full-throttle vacuum) with nine cars.

Not Available

1985-07-01T23:59:59.000Z

444

Status report of advanced cladding modeling work to assess cladding performance under accident conditions  

SciTech Connect (OSTI)

Scoping simulations performed using a severe accident code can be applied to investigate the influence of advanced materials on beyond design basis accident progression and to identify any existing code limitations. In 2012 an effort was initiated to develop a numerical capability for understanding the potential safety advantages that might be realized during severe accident conditions by replacing Zircaloy components in light water reactors (LWRs) with silicon carbide (SiC) components. To this end, a version of the MELCOR code, under development at the Sandia National Laboratories in New Mexico (SNL/NM), was modified by replacing Zircaloy for SiC in the MELCOR reactor core oxidation and material properties routines. The modified version of MELCOR was benchmarked against available experimental data to ensure that present SiC oxidation theory in air and steam were correctly implemented in the code. Additional modifications have been implemented in the code in 2013 to improve the specificity in defining components fabricated from non-standard materials. An overview of these modifications and the status of their implementation are summarized below.

B.J. Merrill; Shannon M. Bragg-Sitton

2013-09-01T23:59:59.000Z

445

Seasonal variations of semidiurnal tidal perturbations in mesopause region temperature and zonal and meridional winds above  

E-Print Network [OSTI]

.1029/2007JD009687. 1. Introduction [2] Solar thermal tides are global-scale waves that dom- inate to conserve wave energy. When propagating into the MLT region, the horizontal wind tidal amplitude can reach with fluorescence lidar's advantages of high temporal and spatial resolution and the capability of full diurnal

446

Role of ocean heat transport in climates of tidally locked exoplanets around M dwarf stars  

E-Print Network [OSTI]

stellar radiation, ocean heat transport can even lead to complete deglaciation of the nightside. OurRole of ocean heat transport in climates of tidally locked exoplanets around M dwarf stars Yongyun Hu1 and Jun Yang Laboratory for Climate and Atmosphere­Ocean Studies, Department of Atmospheric

Hu, Yongyun

447

Gravity and tectonic patterns of Mercury: Effect of tidal deformation, spin-orbit resonance, nonzero  

E-Print Network [OSTI]

Gravity and tectonic patterns of Mercury: Effect of tidal deformation, spin-orbit resonance of spin-orbit resonance, nonzero eccentricity, despinning, and reorientation on Mercury's gravity and tectonic pattern. Large variations of the gravity and shape coefficients from the synchronous rotation

Nimmo, Francis

448

Covariation of coastal water temperature and microbial pollution at interannual to tidal periods  

E-Print Network [OSTI]

Covariation of coastal water temperature and microbial pollution at interannual to tidal periods, California, USA Daniel B. Lluch-Cota Centro de Investigaciones Biologicas del Noroeste, La Paz, Mexico-period cooling are coincident with elevated levels of microbial pollution in the surf zone. This relationship can

Winant, Clinton D.

449

Dissolved oxygen stratification in two micro-tidal partially-mixed estuaries  

E-Print Network [OSTI]

Dissolved oxygen stratification in two micro-tidal partially-mixed estuaries Jing Lin a,*, Lian Xie online 21 August 2006 Abstract The controlling physical factors for vertical oxygen stratification that vertical stratification of dissolved oxygen (DO) concentration can be explained by the extended Hansen

Mallin, Michael

450

Asymmetry of Tidal Plume Fronts in an Eastern Boundary Current Regime  

E-Print Network [OSTI]

water mass. This vorticity controls the transition of the tidal plume 2 #12;front to a subcritical state bulge, which in turn is embedded in far-field plume and coastal waters. Because of the mixing caused on its upwind or northern side) and marks a transition from supercritical to subcritical flow for 6

Jay, David

451

Asymmetry of Columbia River tidal plume fronts David A. Jay a,  

E-Print Network [OSTI]

or northern side and mark a transition from supercritical to subcritical flow for up to 12 h after high water plume water mass. This vorticitycontrols the transition of the tidal plume front to a subcritical state plume may overlie newly upwelled waters, these fronts can mix nutrients into the plume. Symmetry would

Hickey, Barbara

452

Marine Tidal Current Electric Power Generation Technology: State of the Art and Current Status  

E-Print Network [OSTI]

resurgence in development of renewable ocean energy technology. Therefore, several demonstration projects appreciated as a vast renewable energy source. The energy is stored in oceans partly as thermal energy, partly categories: wave energy, marine and tidal current energy, ocean thermal energy, energy from salinity

Paris-Sud XI, Université de

453

Assessing Soil and Hydrologic Properties for the Successful Creation of Non-Tidal Wetlands  

E-Print Network [OSTI]

1 Assessing Soil and Hydrologic Properties for the Successful Creation of Non-Tidal Wetlands W. Lee, VA 23529-0276 rwhittec@odu.edu Introduction Federal and state wetlands protection regulations require the mitigation of impacts to jurisdictional wetlands via avoidance and minimization of damage whenever possible

Darby, Dennis

454

Refinement and validation of a multi-level assessment method for Mid-Atlantic tidal wetlands  

E-Print Network [OSTI]

Refinement and validation of a multi-level assessment method for Mid-Atlantic tidal wetlands (EPA of wetland resources across the Mid-Atlantic physiographic region, efforts are currently underway in a number of states, most notably Delaware, Maryland, Pennsylvania and Virginia, to develop and implement wetland

455

Inventory and Ventilation Efficiency of Nonnative and Native Phragmites australis (Common Reed) in Tidal  

E-Print Network [OSTI]

NOTE Inventory and Ventilation Efficiency of Nonnative and Native Phragmites australis (Common Reed: 3 July 2012 # Coastal and Estuarine Research Federation 2012 Abstract Nonnative Phragmites is among the most in- vasive plants in the U.S. Atlantic coast tidal wetlands, whereas the native Phragmites has

456

Summary report on the fuel performance modeling of the AFC-2A, 2B irradiation experiments  

SciTech Connect (OSTI)

The primary objective of this work at the Idaho National Laboratory (INL) is to determine the fuel and cladding temperature history during irradiation of the AFC-2A, 2B transmutation metallic fuel alloy irradiation experiments containing transuranic and rare earth elements. Addition of the rare earth elements intends to simulate potential fission product carry-over from pyro-metallurgical reprocessing. Post irradiation examination of the AFC-2A, 2B rodlets revealed breaches in the rodlets and fuel melting which was attributed to the release of the fission gas into the helium gap between the rodlet cladding and the capsule which houses six individually encapsulated rodlets. This release is not anticipated during nominal operation of the AFC irradiation vehicle that features a double encapsulated design in which sodium bonded metallic fuel is separated from the ATR coolant by the cladding and the capsule walls. The modeling effort is focused on assessing effects of this unanticipated event on the fuel and cladding temperature with an objective to compare calculated results with the temperature limits of the fuel and the cladding.

Pavel G. Medvedev

2013-09-01T23:59:59.000Z

457

Thermal performance sensitivity studies in support of material modeling for extended storage of used nuclear fuel  

SciTech Connect (OSTI)

The work reported here is an investigation of the sensitivity of component temperatures of a storage system, including fuel cladding temperatures, in response to age-related changes that could degrade the design-basis thermal behavior of the system. Three specific areas of interest were identified for this study. • degradation of the canister backfill gas from pure helium to a mixture of air and helium, resulting from postulated leakage due to stress corrosion cracking (SCC) of canister welds • changes in surface emissivity of system components, resulting from corrosion or other aging mechanisms, which could cause potentially significant changes in temperatures and temperature distributions, due to the effect on thermal radiation exchange between components • changes in fuel and basket temperatures due to changes in fuel assembly position within the basket cells in the canister The purpose of these sensitivity studies is to provide a realistic example of how changes in the physical properties or configuration of the storage system components can affect temperatures and temperature distributions. The magnitudes of these sensitivities can provide guidance for identifying appropriate modeling assumptions for thermal evaluations extending long term storage out beyond 50, 100, 200, and 300 years.

Cuta, Judith M.; Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.

2013-08-15T23:59:59.000Z

458

User's guide to DIANE Version 2. 1: A microcomputer software package for modeling battery performance in electric vehicle applications  

SciTech Connect (OSTI)

DIANE is an interactive microcomputer software package for the analysis of battery performance in electric vehicle (EV) applications. The principal objective of this software package is to enable the prediction of EV performance on the basis of laboratory test data for batteries. The model provides a second-by-second simulation of battery voltage and current for any specified velocity/time or power/time profile. The capability of the battery is modeled by an algorithm that relates the battery voltage to the withdrawn current, taking into account the effect of battery depth-of-discharge (DOD). Because of the lack of test data and other constraints, the current version of DIANE deals only with vehicles using fresh'' batteries with or without regenerative braking. Deterioration of battery capability due to aging can presently be simulated with user-input parameters accounting for an increase of effective internal resistance and/or a decrease of cell no-load voltage. DIANE 2.1 is written in FORTRAN language for use on IBM-compatible microcomputers. 7 refs.

Marr, W.W.; Walsh, W.J. (Argonne National Lab., IL (USA). Energy Systems Div.); Symons, P.C. (Electrochemical Engineering Consultants, Inc., Morgan Hill, CA (USA))

1990-06-01T23:59:59.000Z

459

Pool spacing, channel morphology, and the restoration of tidal forested wetlands of the Columbia River, U.S.A.  

SciTech Connect (OSTI)

Tidal forested wetlands have sustained substantial areal losses, and restoration practitioners lack a description of many ecosystem structures associated with these late-successional systems in which surface water is a significant controlling factor on the flora and fauna. The roles of large woody debris in terrestrial and riverine ecosystems have been well described compared to functions in tidal areas. This study documents the role of large wood in forcing channel morphology in Picea-sitchensis (Sitka spruce) dominated freshwater tidal wetlands in the floodplain of the Columbia River, U.S.A. near the Pacific coast. The average pool spacing documented in channel surveys of three freshwater tidal forested wetlands near Grays Bay were 2.2 ± 1.3, 2.3 ± 1.2, and 2.5 ± 1.5. There were significantly greater numbers of pools on tidal forested wetland channels than on a nearby restoration site. On the basis of pool spacing and the observed sequences of log jams and pools, the tidal forested wetland channels were classified consistent with a forced step-pool class. Tidal systems, with bidirectional flow, have not previously been classified in this way. The classification provides a useful basis for restoration project design and planning in historically forested tidal freshwater areas, particularly in regard to the use of large wood in restoration actions and the development of pool habitats for aquatic species. Significant modifications by beaver on these sites warrant further investigation to explore the interactions between these animals and restoration actions affecting hydraulics and channel structure in tidal areas.

Diefenderfer, Heida L.; Montgomery, David R.

2008-10-09T23:59:59.000Z

460

Long-term performance of ceramic matrix composites at elevated temperatures: Modelling of creep and creep rupture  

SciTech Connect (OSTI)

The models developed, contain explicit dependences on constituent material properties and their changes with time, so that composite performance can be predicted. Three critical processes in ceramic composites at elevated temperatures have been modeled: (1) creep deformation of composite vs stress and time-dependent creep of fibers and matrix, and failure of these components; (2) creep deformation of ``interface`` around broken fibers; and (3) lifetime of the composite under conditions of fiber strength loss over time at temperature. In (1), general evolution formulas are derived for relaxation time of matrix stresses and steady-state creep rate of composite; the model is tested against recent data on Ti-MMCs. Calculations on a composite of Hi-Nicalon fibers in a melt-infiltrated SiC matrix are presented. In (2), numerical simulations of composite failure were made to map out time-to-failure vs applied load for several sets of material parameters. In (3), simple approximate relations are obtained between fiber life and composite life that should be useful for fiber developers and testers. Strength degradation data on Hi-Nicalon fibers is used to assess composite lifetime vs fiber lifetime for Hi-Nicalon fiber composites.

Curtin, W.A.; Fabeny, B.; Ibnabdeljalil, M.; Iyengar, N.; Reifsnider, K.L. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Engineering Science and Mechanics

1996-07-31T23:59:59.000Z

Note: This page contains sample records for the topic "modeling performance tidal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Review and perspectives on spallings release models in the 1996 performance assessment for the Waste Isolation Pilot Plant  

SciTech Connect (OSTI)

The Waste Isolation Pilot Plant was licensed for disposal of transuranic wastes generated by the US Department of Energy. The facility consists of a repository mined in a bedded salt formation, approximately 650 m below the surface. Regulations promulgated by the US Environmental Protection Agency require that performance assessment calculations for the repository include the possibility that an exploratory drilling operation could penetrate the waste disposal areas at some time in the future. Release of contaminated solids could reach the surface during a drilling intrusion. One of the mechanisms for release, known as spallings, can occur if gas pressures in the repository exceed the hydrostatic pressure of a column of drilling mud. Calculation of solids releases for spallings depends critically on the conceptual models for the waste, for the spallings process, and assumptions regarding driller parameters and practices. The paper presents a review of the evolution of these models during regulatory review of the Compliance Certification Application for the repository. A summary and perspectives on the implementation of conservative assumptions in model development are also provided.

Knowles, M.K; Hansen, F.D.; Thompson, T.W.; Schatz, J.F.; Gross, M.

2000-05-22T23:59:59.000Z