Powered by Deep Web Technologies
Note: This page contains sample records for the topic "modeling cycling units" 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

Assessment of Mercury Emissions, Transport, Fate, and Cycling for the Continental United States: Model Structure and Evaluation  

Science Conference Proceedings (OSTI)

New findings on mercury emissions, cycling, and fate have allowed the development of improved simulation tools and the assembly of verification data sets for modeling mercury transport and deposition. This report describes new simulations of mercury emissions, transport, and deposition from the atmosphere that form an important first step in for relating mercury concentrations and deposition rates at particular geographic locations to their ultimate source regions.

2000-12-15T23:59:59.000Z

2

Dynamic Mercury Cycling Model Upgrade  

Science Conference Proceedings (OSTI)

This technical update describes the status of activities to upgrade the Dynamic Mercury Cycling Model (D-MCM), an EPRI simulation model that predicts mercury cycling and bioaccumulation in lakes.

2008-12-17T23:59:59.000Z

3

Rigorous Kinetic Modeling, Optimization, and Operability Studies of a Modified Claus Unit for an Integrated Gasification Combined Cycle (IGCC) Power Plant with CO{sub 2} Capture  

Science Conference Proceedings (OSTI)

The modified Claus process is one of the most common technologies for sulfur recovery from acid gas streams. Important design criteria for the Claus unit, when part of an Integrated Gasification Combined Cycle (IGCC) power plant, are the ability to destroy ammonia completely and the ability to recover sulfur thoroughly from a relatively low purity acid gas stream without sacrificing flame stability. Because of these criteria, modifications to the conventional process are often required, resulting in a modified Claus process. For the studies discussed here, these modifications include the use of a 95% pure oxygen stream as the oxidant, a split flow configuration, and the preheating of the feeds with the intermediate pressure steam generated in the waste heat boiler (WHB). In the future, for IGCC plants with CO{sub 2} capture, the Claus unit must satisfy emission standards without sacrificing the plant efficiency in the face of typical disturbances of an IGCC plant, such as rapid change in the feed flow rates due to load-following and wide changes in the feed composition because of changes in the coal feed to the gasifier. The Claus unit should be adequately designed and efficiently operated to satisfy these objectives. Even though the Claus process has been commercialized for decades, most papers concerned with the modeling of the Claus process treat the key reactions as equilibrium reactions. Such models are validated by manipulating the temperature approach to equilibrium for a set of steady-state operating data, but they are of limited use for dynamic studies. One of the objectives of this study is to develop a model that can be used for dynamic studies. In a Claus process, especially in the furnace and the WHB, many reactions may take place. In this work, a set of linearly independent reactions has been identified, and kinetic models of the furnace flame and anoxic zones, WHB, and catalytic reactors have been developed. To facilitate the modeling of the Claus furnace, a four-stage method was devised so as to determine which set of linearly independent reactions would best describe the product distributions from available plant data. Various approaches are taken to derive the kinetic rate expressions, which are either missing in the open literature or found to be inconsistent. A set of plant data is used for optimal estimation of the kinetic parameters. The final model agrees well with the published plant data. Using the developed kinetics models of the Claus reaction furnace, WHB, and catalytic stages, two optimization studies are carried out. The first study shows that there exists an optimal steam pressure generated in the WHB that balances hydrogen yield, oxygen demand, and power generation. In the second study, it is shown that an optimal H{sub 2}S/SO{sub 2} ratio exists that balances single-pass conversion, hydrogen yield, oxygen demand, and power generation. In addition, an operability study has been carried out to examine the operating envelope in which both the H{sub 2}S/SO{sub 2} ratio and the adiabatic flame temperature can be controlled in the face of disturbances typical for the operation of an IGCC power plant with CO{sub 2} capture. Impact of CO{sub 2} capture on the Claus process has also been discussed.

Jones, Dustin; Bhattacharyya, Debangsu; Turton, Richard; Zitney, Stephen E

2011-12-15T23:59:59.000Z

4

Rigorous Kinetic Modeling and Optimization Study of a Modified Claus Unit for an Integrated Gasification Combined Cycle (IGCC) Power Plant with CO{sub 2} Capture  

SciTech Connect

The modified Claus process is one of the most common technologies for sulfur recovery from acid gas streams. Important design criteria for the Claus unit, when part of an Integrated Gasification Combined Cycle (IGCC) power plant, are the ability to destroy ammonia completely and the ability to recover sulfur thoroughly from a relatively low purity acid gas stream without sacrificing flame stability. Because of these criteria, modifications to the conventional process are often required, resulting in a modified Claus process. For the studies discussed here, these modifications include the use of a 95% pure oxygen stream as the oxidant, a split flow configuration, and the preheating of the feeds with the intermediate pressure steam generated in the waste heat boiler (WHB). In the future, for IGCC plants with CO{sub 2} capture, the Claus unit must satisfy emission standards without sacrificing the plant efficiency in the face of typical disturbances of an IGCC plant, such as rapid change in the feed flow rates due to load-following and wide changes in the feed composition because of changes in the coal feed to the gasifier. The Claus unit should be adequately designed and efficiently operated to satisfy these objectives. Even though the Claus process has been commercialized for decades, most papers concerned with the modeling of the Claus process treat the key reactions as equilibrium reactions. Such models are validated by manipulating the temperature approach to equilibrium for a set of steady-state operating data, but they are of limited use for dynamic studies. One of the objectives of this study is to develop a model that can be used for dynamic studies. In a Claus process, especially in the furnace and the WHB, many reactions may take place. In this work, a set of linearly independent reactions has been identified, and kinetic models of the furnace flame and anoxic zones, WHB, and catalytic reactors have been developed. To facilitate the modeling of the Claus furnace, a four-stage method was devised so as to determine which set of linearly independent reactions would best describe the product distributions from available plant data. Various approaches are taken to derive the kinetic rate expressions, which are either missing in the open literature or found to be inconsistent. A set of plant data is used for optimal estimation of the kinetic parameters. The final model agrees well with the published plant data. Using the developed kinetics models of the Claus reaction furnace, WHB, and catalytic stages, two optimization studies are carried out. The first study shows that there exists an optimal steam pressure generated in the WHB that balances hydrogen yield, oxygen demand, and power generation. In the second study, it is shown that an optimal H{sub 2}S/SO{sub 2} ratio exists that balances single-pass conversion, hydrogen yield, oxygen demand, and power generation. In addition, an operability study has been carried out to examine the operating envelope in which both the H{sub 2}S/SO{sub 2} ratio and the adiabatic flame temperature can be controlled in the face of disturbances typical for the operation of an IGCC power plant with CO{sub 2} capture. Impact of CO{sub 2} capture on the Claus process has also been discussed.

Jones, Dustin; Bhattacharyya, Debangsu; Turton, Richard; Zitney, Stephen E.

2012-02-08T23:59:59.000Z

5

Regional Simulation of Intraseasonal Variations in the Summertime Hydrologic Cycle over the Southwestern United States  

Science Conference Proceedings (OSTI)

Using results taken from a finescale (25 km) regional modeling simulation for the summer of 1999, intraseasonal variations in the climatological summertime hydrologic cycle over the southwestern United States are described for two previously ...

Bruce T. Anderson

2002-09-01T23:59:59.000Z

6

Air Handling Unit Supply Air Temperature Optimization During Economizer Cycles  

E-Print Network (OSTI)

Most air handling units (AHUs) in commercial buildings have an air economizer cycle for free cooling under certain outside air conditions. During the economizer cycle, the outside air and return air dampers are modulated to seek mixing air temperature at supply air temperature setpoint. Mechanical cooling is always required when outside air temperature is higher than the supply air temperature setpoint. Generally the supply air temperature setpoint is set at 55°F for space humidity control. Actually the dehumidification is not necessary when outside air dew point is less than 55°F. Meanwhile the space may have less cooling load due to envelope heat loss and/or occupant schedule. These provide an opportunity to use higher supply air temperature to reduce or eliminate mechanical cooling and terminal box reheat. On the other hand the higher supply air temperature will require higher air flow as well as higher fan power. Therefore the supply air temperature has to be optimized to minimize the combined energy for fan, cooling and heating energy. In this paper a simple energy consumption model is established for AHU systems during the economizer and then a optimal supply air temperature control is developed to minimize the total cost of the mechanical cooling and the fan motor power. This paper presents AHU system energy modeling, supply air temperature optimization, and simulated energy savings.

Xu, K.; Liu, M.; Wang, G.; Wang, Z.

2007-01-01T23:59:59.000Z

7

Cycling Operation of Fossil Plants: Volume 1: Cycling Considerations for Niagara Mohawk's Oswego Unit 5  

Science Conference Proceedings (OSTI)

Fossil plants are being converted to cycling operation to accommodate daily load swings and to decrease the overall system fuel costs. This report summarizes the methods and results of an engineering study of three two-shift cycling approaches considered for Niagara Mohawk's Oswego unit 5: superheater/turbine bypass, variable pressure operations, and full-flow condensate polishing.

1991-05-01T23:59:59.000Z

8

Cycle Chemistry Guidelines for Shutdown, Layup, and Startup of Combined Cycle Units with Heat Recovery Steam Generators  

Science Conference Proceedings (OSTI)

Complete optimization of cycle chemistry in a combined-cycle unit requires more than proper selection and optimization of operating chemistry. Protection of the steam-water cycle also is essential during shutdown, layup, and startup phases. These guidelines consider protection of steam- and water-touched components at these times, consistent with the operating cycle chemistries in use.

2006-03-21T23:59:59.000Z

9

High-Resolution Observations and Model Simulations of the Life Cycle of an Intense Mesoscale Snowband over the Northeastern United States  

Science Conference Proceedings (OSTI)

This paper investigates the structural and dynamical evolution of an intense mesoscale snowband occurring 25–26 December 2002 over the northeastern United States. Dual-Doppler, wind profiler, aircraft, and water vapor observations in concert with ...

David R. Novak; Brian A. Colle; Sandra E. Yuter

2008-04-01T23:59:59.000Z

10

Westinghouse to launch coal gasifier with combined cycle unit  

Science Conference Proceedings (OSTI)

Westinghouse has designed a prototype coal gasifier which can be intergrated with a combined cycle unit and enable power plants to use coal in an efficient and environmentally acceptable way. Coal Gasification Combined Cycle (CGCC) technology burns gas made from coal in a gas turbine to generate power and then collects the hot exhaust gases to produce steam for further power generation. The commercialization of this process would meet the public's need for an economical and clean way to use coal, the utitities' need to meet electric power demands, and the nation's need to reduce dependence on imported oil. The Westinghouse process is described along with the company's plans for a demonstration plant and the option of a phased introduction to allow utilities to continue the use of existing equipment and generate revenue while adding to capacity. (DCK)

Stavsky, R.M.; Margaritis, P.J.

1980-03-01T23:59:59.000Z

11

The Seasonal Cycle over the United States and Mexico  

Science Conference Proceedings (OSTI)

The annual cycle occupies a unique position in the spectra of meteorological time series. This cycle and its first three harmonics are extracted from the series as a seasonal cycle. The distributions of the annual and seasonal cycles are studied ...

Vernon E. Kousky; S. Srivatsangam

1983-01-01T23:59:59.000Z

12

VISION: Verifiable Fuel Cycle Simulation Model  

Science Conference Proceedings (OSTI)

The nuclear fuel cycle is a very complex system that includes considerable dynamic complexity as well as detail complexity. In the nuclear power realm, there are experts and considerable research and development in nuclear fuel development, separations technology, reactor physics and waste management. What is lacking is an overall understanding of the entire nuclear fuel cycle and how the deployment of new fuel cycle technologies affects the overall performance of the fuel cycle. The Advanced Fuel Cycle Initiative’s systems analysis group is developing a dynamic simulation model, VISION, to capture the relationships, timing and delays in and among the fuel cycle components to help develop an understanding of how the overall fuel cycle works and can transition as technologies are changed. This paper is an overview of the philosophy and development strategy behind VISION. The paper includes some descriptions of the model and some examples of how to use VISION.

Jacob J. Jacobson; Abdellatif M. Yacout; Gretchen E. Matthern; Steven J. Piet; David E. Shropshire

2009-04-01T23:59:59.000Z

13

VISION: Verifiable Fuel Cycle Simulation Model  

SciTech Connect

The nuclear fuel cycle consists of a set of complex components that work together in unison. In order to support the nuclear renaissance, it is necessary to understand the impacts of changes and timing of events in any part of the fuel cycle system. The Advanced Fuel Cycle Initiative’s systems analysis group is developing a dynamic simulation model, VISION, to capture the relationships, timing, and changes in and among the fuel cycle components to help develop an understanding of how the overall fuel cycle works. This paper is an overview of the philosophy and development strategy behind VISION. The paper includes some descriptions of the model components and some examples of how to use VISION.

Jacob Jacobson; A. M. Yacout; Gretchen Matthern; Steven Piet; David Shropshire; Tyler Schweitzer

2010-11-01T23:59:59.000Z

14

Enhanced absorption cycle computer model. Final report  

DOE Green Energy (OSTI)

Absorption heat pumps have received renewed and increasing attention in the past two decades. The rising cost of electricity has made the particular features of this heat-powered cycle attractive for both residential and industrial applications. Solar-powered absorption chillers, gas-fired domestic heat pumps, and waste-heat-powered industrial temperatures boosters are a few of the applications recently subjected to intensive research and development. The absorption heat pump research community has begun to search for both advanced cycles in various multistage configurations and new working fluid combinations with potential for enhanced performance and reliability. The development of working absorptions systems has created a need for reliable and effective system simulations. A computer code has been developed for simulation of absorption systems at steady state in a flexible and modular form, making it possible to investigate various cycle configurations with different working fluids. The code is based on unit subroutines containing the governing equations for the system`s components and property subroutines containing thermodynamic properties of the working fluids. The user conveys to the computer an image of his cycle by specifying the different subunits and their interconnections. Based on this information, the program calculates the temperature, flow rate, concentration, pressure, and vapor fraction at each state point in the system, and the heat duty at each unit, from which the coefficient of performance (COP) may be determined. This report describes the code and its operation, including improvements introduced into the present version. Simulation results are described for LiBr-H{sub 2}O triple-effect cycles, LiCl-H{sub 2}O solar-powered open absorption cycles, and NH{sub 3}-H{sub 2}O single-effect and generator-absorber heat exchange cycles. An appendix contains the User`s Manual.

Grossman, G.; Wilk, M. [Technion-Israel Inst. of Tech., Haifa (Israel). Faculty of Mechanical Engineering

1993-09-01T23:59:59.000Z

15

End-of-Cycle 11 Examinations at Farley Unit 2  

Science Conference Proceedings (OSTI)

Evaluation of data from non-zinc Cycle 11 and zinc Cycle 10 confirmed that addition of zinc to the primary coolant is beneficial in reducing radiation dose rates. The data also indicated that zinc does not have an adverse effect on fuel cladding corrosion.

1997-08-06T23:59:59.000Z

16

Large-Scale Aspects of the United States Hydrologic Cycle  

Science Conference Proceedings (OSTI)

A large-scale, gridpoint, atmospheric, hydrologic climatology consisting of atmospheric precipitable water, precipitation, atmospheric moisture flux convergence, and a residual evaporation for the conterminous United States is described. A large-...

John O. Roads; Shyh-C. Chen; Alexander K. Guetter; Konstantine P. Georgakakos

1994-09-01T23:59:59.000Z

17

Seasonal Cycle Shifts in Hydroclimatology over the Western United States  

Science Conference Proceedings (OSTI)

Analyses of streamflow, snow mass temperature, and precipitation in snowmelt-dominated river basins in the western United States indicate an advance in the timing of peak spring season flows over the past 50 years. Warm temperature spells in ...

Satish Kumar Regonda; Balaji Rajagopalan; Martyn Clark; John Pitlick

2005-01-01T23:59:59.000Z

18

Source to tap urban water cycle modelling  

Science Conference Proceedings (OSTI)

The continuous expansion of urban areas is associated with increased water demand, both for domestic and non-domestic uses. To cover this additional demand, centralised infrastructure, such as water supply and distribution networks tend to become more ... Keywords: Metabolism models, Optimisation, Urban water cycle, Water demand management

Evangelos Rozos; Christos Makropoulos

2013-03-01T23:59:59.000Z

19

Impacts of Renewable Generation on Fossil Fuel Unit Cycling: Costs and Emissions (Presentation)  

Science Conference Proceedings (OSTI)

Prepared for the Clean Energy Regulatory Forum III, this presentation looks at the Western Wind and Solar Integration Study and reexamines the cost and emissions impacts of fossil fuel unit cycling.

Brinkman, G.; Lew, D.; Denholm, P.

2012-09-01T23:59:59.000Z

20

Predicting solar cycle 24 with a solar dynamo model  

E-Print Network (OSTI)

Whether the upcoming cycle 24 of solar activity will be strong or not is being hotly debated. The solar cycle is produced by a complex dynamo mechanism. We model the last few solar cycles by `feeding' observational data of the Sun's polar magnetic field into our solar dynamo model. Our results fit the observed sunspot numbers of cycles 21-23 extremely well and predict that cycle~24 will be about 35% weaker than cycle~23.

Arnab Rai Choudhuri; Piyali Chatterjee; Jie Jiang

2007-01-18T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

The Velocity of Money in a Life-Cycle Model  

E-Print Network (OSTI)

The determinants of the velocity of money have been examined based on life-cycle hypothesis. The velocity of money can be expressed by reciprocal of the average value of holding time which is defined as interval between participating exchanges for one unit of money. This expression indicates that the velocity is governed by behavior patterns of economic agents and open a way to constructing micro-foundation of it. It is found that time pattern of income and expense for a representative individual can be obtained from a simple version of life-cycle model, and average holding time of money resulted from the individual's optimal choice depends on the expected length of relevant planning periods.

Wang, Y; Wang, Yougui; Qiu, Hanqing

2005-01-01T23:59:59.000Z

22

Fuzzy modeling of fluidized catalytic cracking unit  

Science Conference Proceedings (OSTI)

The paper deals with the fuzzy system identification of reactor-regenerator-stripper-fractionator's (RRSF) section of a fluidized catalytic cracking unit (FCCU). The fuzzy system identification based on the data collected from an operating refinery of ... Keywords: Dynamic fuzzy model, FCCU models, Fuzzy clustering, Fuzzy inference systems, Fuzzy models, Hybrid learning, Mountain clustering, Supervised learning, Unsupervised learning

Mohammad Fazle Azeem; Nesar Ahmad; M. Hanmandlu

2007-01-01T23:59:59.000Z

23

An H infinity (H?) design scheme for an air blown gasification cycle unit using matlab  

Science Conference Proceedings (OSTI)

The purpose of this paper is to use the H? design technique in order to produce an efficient controller for a real application, which concerns the design of a control scheme for an air blown gasification cycle unit plant (gasifier) for the production ... Keywords: H?, close loop, gasifier, matlab, multivariate analysis, open loop, robustness, stability

Stylianos SP. Pappas

2006-12-01T23:59:59.000Z

24

Seasonal and Spatial Patterns in Diurnal Cycles in Streamflow in the Western United States  

Science Conference Proceedings (OSTI)

The diurnal cycle in streamflow constitutes a significant part of the variability in many rivers in the western United States and can be used to understand some of the dominant processes affecting the water balance of a given river basin. Rivers ...

Jessica D. Lundquist; Daniel R. Cayan

2002-10-01T23:59:59.000Z

25

Evaluation of Fuel Cladding Corrosion and Corrosion Product Deposits from Ulchin Unit 1 Cycle 17  

Science Conference Proceedings (OSTI)

This report documents the results of a fuel surveillance campaign at Ulchin Unit 1 following its first cycle of zinc injection. Zinc has been shown to have a positive impact on shutdown radiation fields and is beneficial for primary water stress corrosion cracking (PWSCC) initiation of susceptible primary system materials.

2011-12-23T23:59:59.000Z

26

Efficient Modelling of Fast Cycle Adsorption for the Separation...  

NLE Websites -- All DOE Office Websites (Extended Search)

the rate of cycling major increases in throughput can also be achieved. Objective Modelling a PSA system is inherently complex and hence our aim is to find valid...

27

An Integrated Life Cycle Engineering Model: Energy and Greenhouse...  

NLE Websites -- All DOE Office Websites (Extended Search)

An Integrated Life Cycle Engineering Model: Energy and Greenhouse Gas Performance of Residential Heritage Buildings, and the Influence of Retrofit Strategies and Appliance...

28

Evaluation of Zinc Addition During Cycle 9 at Diablo Canyon Unit 1  

Science Conference Proceedings (OSTI)

Laboratory studies have shown that zinc addition to primary coolant can mitigate primary water stress corrosion cracking (PWSCC) of Alloy 600 and reduce radiation fields in PWRs. This report documents experience with zinc addition during Cycle 9 at Diablo Canyon Power Plant Unit 1 (DCPP-1), operated by Pacific Gas & Electric. This project evaluated the effect of zinc addition on PWSCC initiation and propagation. It also examined the impact of zinc addition on radiation fields and fuel cladding deposition...

1999-10-27T23:59:59.000Z

29

Software Requirements Specification Verifiable Fuel Cycle Simulation (VISION) Model  

SciTech Connect

The purpose of this Software Requirements Specification (SRS) is to define the top-level requirements for a Verifiable Fuel Cycle Simulation Model (VISION) of the Advanced Fuel Cycle (AFC). This simulation model is intended to serve a broad systems analysis and study tool applicable to work conducted as part of the AFCI (including costs estimates) and Generation IV reactor development studies.

D. E. Shropshire; W. H. West

2005-11-01T23:59:59.000Z

30

ORNL researchers improve soil carbon cycling models | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

researchers improve soil carbon cycling models researchers improve soil carbon cycling models January 01, 2013 ORNL's new carbon cycling model could help scientists understand the role of soil microbes (MBC) in climate change by tracking extracellular enzymes (ENZ) that break down carbon-rich soil materials (SOC) into forms that microbes can respire (DOC). A more robust model of the soil carbon cycle developed at Oak Ridge National Laboratory (ORNL) improves understanding of carbon residence time in soils and enables scientists to make more accurate climate predictions. The model does a better job than previous models of accounting for how microbes in the soil break down carbon-rich materials and release carbon dioxide. "Soil is a big reservoir of carbon," said co-author Melanie Mayes of the Environmental Sciences Division and the Climate Change Science

31

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials Prospective Life-Cycle Modeling of Novel Carbon Capture Materials Speaker(s): Roger Sathre Date: December 5, 2011 - 3:30pm Location: 90-4133 Seminar Host/Point of Contact: Anita Estner Barbara Adams In this presentation we describe the prospective life-cycle modeling of metal-organic frameworks (MOF), a novel type of material with the potential for efficiently capturing CO2. Life-cycle modeling of emerging technologies, conducted early in the innovation process, can generate knowledge that can feed back to inform scientific discovery and development. We discuss the challenges of credibly modeling a system that does not yet exist, and describe methodological approaches including parametric system modeling (quantifying relations between system elements), scenario projections (defining plausible pathways for system scale-up),

32

Modeling the Solar Cycle: What the Future Holds  

E-Print Network (OSTI)

Stellar magnetic fields are produced by a magnetohydrodynamic dynamo mechanism working in their interior -- which relies on the interaction between plasma flows and magnetic fields. The Sun, being a well-observed star, offers an unique opportunity to test theoretical ideas and models of stellar magnetic field generation. Solar magnetic fields produce sunspots, whose number increases and decreases with a 11 year periodicity -- giving rise to what is known as the solar cycle. Dynamo models of the solar cycle seek to understand its origin, variation and evolution with time. In this review, I summarize observations of the solar cycle and describe theoretical ideas and dynamo modeling efforts to address its origin. I end with a discussion on the future of solar cycle modeling -- emphasizing the importance of a close synergy between observational data assimilation, kinematic dynamo models and full magnetohydrodynamic models of the solar interior.

Nandy, Dibyendu

2011-01-01T23:59:59.000Z

33

Semantic modelling of dependency relations between life cycle analysis processes  

Science Conference Proceedings (OSTI)

Life Cycle Assessment provides a well-accepted methodology for modelling environmental impacts of human activities. This methodology relies on the decomposition of a studied system into interdependent processes. Several organisations provide processes ... Keywords: environmental information management, life cycle assessment, ontology

Benjamin Bertin; Marian Scuturici; Jean-Marie Pinon; Emmanuel Risler

2012-09-01T23:59:59.000Z

34

An Economic Analysis of Select Fuel Cycles Using the Steady-State Analysis Model for Advanced Fuel Cycles Schemes (SMAFS)  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy's (DOE) Global Nuclear Energy Partnership (GNEP) is currently considering alternatives to the current U.S. once-through fuel cycle. This report evaluates the relative economics of three alternative fuel cycles to determine those cost components important to overall fuel cycle costs and total generation costs. The analysis determined that the unit cost of nuclear reactors is the most important nuclear generation cost parameter in future fuel cycles. The report also evaluates ...

2007-12-20T23:59:59.000Z

35

Fuel cycle assessment: A compendium of models, methodologies, and approaches  

SciTech Connect

The purpose of this document is to profile analytical tools and methods which could be used in a total fuel cycle analysis. The information in this document provides a significant step towards: (1) Characterizing the stages of the fuel cycle. (2) Identifying relevant impacts which can feasibly be evaluated quantitatively or qualitatively. (3) Identifying and reviewing other activities that have been conducted to perform a fuel cycle assessment or some component thereof. (4) Reviewing the successes/deficiencies and opportunities/constraints of previous activities. (5) Identifying methods and modeling techniques/tools that are available, tested and could be used for a fuel cycle assessment.

Not Available

1994-07-01T23:59:59.000Z

36

HAsim : cycle-accurate multicore performance models on FPGAs  

E-Print Network (OSTI)

The goal of this project is to improve computer architecture by accelerating cycle-accurate performance modeling of multicore processors using FPGAs. Contributions include a distributed technique controlling simulation on ...

Pellauer, Michael (Michael Ignatius)

2011-01-01T23:59:59.000Z

37

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Prospective Life-Cycle Modeling of Novel Carbon Capture Materials Speaker(s): Roger Sathre Date: December 5, 2011 - 3:30pm Location: 90-4133 Seminar HostPoint of Contact: Anita...

38

Internal cycle modeling and environmental assessment of multiple cycle consumer products  

Science Conference Proceedings (OSTI)

Highlights: Black-Right-Pointing-Pointer Dynamic flow models are presented for remanufactured, reused or recycled products. Black-Right-Pointing-Pointer Early loss and stochastic return are included for fast and slow cycling products. Black-Right-Pointing-Pointer The reuse-to-input flow ratio (Internal Cycle Factor, ICF) is determined. Black-Right-Pointing-Pointer The cycle rate, which is increasing with the ICF, monitors eco-performance. Black-Right-Pointing-Pointer Early internal cycle losses diminish the ICF, the cycle rate and performance. - Abstract: Dynamic annual flow models incorporating consumer discard and usage loss and featuring deterministic and stochastic end-of-cycle (EOC) return by the consumer are developed for reused or remanufactured products (multiple cycle products, MCPs), including fast and slow cycling, short and long-lived products. It is shown that internal flows (reuse and overall consumption) increase proportionally to the dimensionless internal cycle factor (ICF) which is related to environmental impact reduction factors. The combined reuse/recycle (or cycle) rate is shown capable for shortcut, albeit effective, monitoring of environmental performance in terms of waste production, virgin material extraction and manufacturing impacts of all MCPs, a task, which physical variables (lifetime, cycling frequency, mean or total number of return trips) and conventional rates, via which environmental policy has been officially implemented (e.g. recycling rate) cannot accomplish. The cycle rate is shown to be an increasing (hyperbolic) function of ICF. The impact of the stochastic EOC return characteristics on total reuse and consumption flows, as well as on eco-performance, is assessed: symmetric EOC return has a small, positive effect on performance compared to deterministic, while early shifted EOC return is more beneficial. In order to be efficient, environmental policy should set higher minimum reuse targets for higher trippage MCPs. The results may serve for monitoring, flow accounting and comparative eco-assessment of MCPs. They may be useful in identifying reachable and efficient reuse/recycle targets for consumer products and in planning return via appropriate labelling and digital coding for enhancing environmental performance, while satisfying consumer demand.

Tsiliyannis, C.A., E-mail: anion@otenet.gr [ANION Environmental Ltd., 26 Lykoudi Str., Athens 11141 (Greece)

2012-01-15T23:59:59.000Z

39

Dynamic LES Modeling of a Diurnal Cycle  

Science Conference Proceedings (OSTI)

The diurnally varying atmospheric boundary layer observed during the Wangara (Australia) case study is simulated using the recently proposed locally averaged scale-dependent dynamic subgrid-scale (SGS) model. This tuning-free SGS model enables ...

Sukanta Basu; Jean-François Vinuesa; Andrew Swift

2008-04-01T23:59:59.000Z

40

National Energy Modeling System (United States) | Open Energy Information  

Open Energy Info (EERE)

National Energy Modeling System (United States) National Energy Modeling System (United States) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: National Energy Modeling System (United States) Focus Area: Biomass Topics: Policy, Deployment, & Program Impact Website: www.eia.gov/oiaf/aeo/overview/ Equivalent URI: cleanenergysolutions.org/content/national-energy-modeling-system-unite Language: English Policies: "Deployment Programs,Regulations" is not in the list of possible values (Deployment Programs, Financial Incentives, Regulations) for this property. DeploymentPrograms: Technical Assistance Regulations: Utility/Electricity Service Costs The National Energy Modeling System (NEMS) is a computer-based, energy-economy modelling system of the United States through 2030. NEMS

Note: This page contains sample records for the topic "modeling cycling units" 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

A Multiyear Regional Climate Hindcast for the Western United States Using the Mesoscale Atmospheric Simulation Model  

Science Conference Proceedings (OSTI)

In preparation for studying the effects of increased CO2 on the hydrologic cycle in the western United States, an 8-yr hindcast was performed using a regional climate model (RCM) driven by the large-scale forcing from the NCEP–NCAR reanalysis. ...

Jinwon Kim; Jung-Eun Lee

2003-10-01T23:59:59.000Z

42

Analytical model for Stirling cycle machine design  

E-Print Network (OSTI)

In order to study further the promising free piston Stirling engine architecture, there is a need of an analytical thermodynamic model which could be used in a dynamical analysis for preliminary design. To aim at more realistic values, the models have to take into account the heat losses and irreversibilities on the engine. An analytical model which encompasses the critical flaws of the regenerator and furthermore the heat exchangers effectivenesses has been developed. This model has been validated using the whole range of the experimental data available from the General Motor GPU-3 Stirling engine prototype. The effects of the technological and operating parameters on Stirling engine performance have been investigated. In addition to the regenerator influence, the effect of the cooler effectiveness is underlined.

Formosa, Fabien; 10.1016/j.enconman.2010.02.010

2013-01-01T23:59:59.000Z

43

Simulating past and future dynamics of natural ecosystems in the United States. Global Biogeochemical Cycles 17(2)1045  

E-Print Network (OSTI)

[1] Simulations of potential vegetation distribution, natural fire frequency, carbon pools, and fluxes are presented for two DGVMs (Dynamic Global Vegetation Models) from the second phase of the Vegetation/Ecosystem Modeling and Analysis Project. Results link vegetation dynamics to biogeochemical cycling for the conterminous United States. Two climate change scenarios were used: a moderately warm scenario from the Hadley Climate Centre and a warmer scenario from the Canadian Climate Center. Both include sulfate aerosols and assume a gradual CO2 increase. Both DGVMs simulate a reduction of southwestern desert areas, a westward expansion of eastern deciduous forests, and the expansion of forests in the western part of the Pacific Northwest and in north-central California. Both DGVMs predict an increase in total biomass burnt in the next century, with a more pronounced increase under the Canadian scenario. Under the Hadley scenario, both DGVMs simulate increases in total carbon stocks. Under the Canadian scenario, both DGVMs simulate a decrease in live vegetation carbon. We identify similarities in model behavior due to the climate forcing and explain differences by the different structure of the models and their different sensitivity to

Dominique Bachelet; Ronald P. Neilson; Thomas Hickler; Raymond J. Drapek; James M. Lenihan; Martin T. Sykes; Benjamin Smith; Stephen Sitch; Kirsten Thonicke

2003-01-01T23:59:59.000Z

44

Integrated Gasification Combined Cycle (IGCC) demonstration project, Polk Power Station -- Unit No. 1. Annual report, October 1993--September 1994  

SciTech Connect

This describes the Tampa Electric Company`s Polk Power Station Unit 1 (PPS-1) Integrated Gasification Combined Cycle (IGCC) demonstration project which will use a Texaco pressurized, oxygen-blown, entrained-flow coal gasifier to convert approximately 2,300 tons per day of coal (dry basis) coupled with a combined cycle power block to produce a net 250 MW electrical power output. Coal is slurried in water, combined with 95% pure oxygen from an air separation unit, and sent to the gasifier to produce a high temperature, high pressure, medium-Btu syngas with a heat content of about 250 Btu/scf (LHV). The syngas then flows through a high temperature heat recovery unit which cools the syngas prior to its entering the cleanup systems. Molten coal ash flows from the bottom of the high temperature heat recovery unit into a water-filled quench chamber where it solidifies into a marketable slag by-product.

NONE

1995-05-01T23:59:59.000Z

45

Secondary steam models of a combined cycle power plant simulator  

Science Conference Proceedings (OSTI)

In this paper, the general description of a full scope simulator for a combined cycle power plant is presented; the antecedents of this work are explained; the basis of the models of the auxiliary and turbine gland steam systems are exposed and some ...

Edgardo J. Roldan-Villasana; Ma. de Jesus Cardoso-Goroztieta; Adriana Verduzco-Bravo; Jorge J. Zorrilla-Arena

2011-04-01T23:59:59.000Z

46

Modelling life cycle and population dynamics of Nostocales (cyanobacteria)  

Science Conference Proceedings (OSTI)

Cyanobacteria of the order Nostocales found in lakes in temperate regions are generally assumed to benefit from climate change. To predict their future development under varying environmental conditions, we developed a mathematical model that simulates ... Keywords: Cylindrospermopsis raciborskii, Hasse diagram, Life cycle, Nostocales, Population dynamics, Shallow lake

K. D. Jöhnk; R. Brüggemann; J. Rücker; B. Luther; U. Simon; B. Nixdorf; C. Wiedner

2011-05-01T23:59:59.000Z

47

Exhibit A: Modeling in Support of Two Unit Operating Configurations |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Modeling in Support of Two Unit Operating Configurations Modeling in Support of Two Unit Operating Configurations Exhibit A: Modeling in Support of Two Unit Operating Configurations Docket No. EO-05-01: Tables showing modeling of emissions from units of the Mirant Potomac Power Plant. Exhibit A: Modeling in Support of Two Unit Operating Configurations More Documents & Publications Comments on Emergency Order to Resume Limited Operation at the Potomac River Generating Station, Alexandria, VA from the Chesapeake Climate Action Network. Comments on Department of Energy's Emergency Order To Resume Limited Operation at Mirant's Potomac River Generating Station and Proposed Mirant Compliance Plan Answer of Potomac Electric Power Company and PJM lnterconnection, L.L.C. to the October 6, 2005 motion filed by the Virginia Department of

48

Life-cycle Environmental Inventory of Passenger Transportation in the United States  

E-Print Network (OSTI)

in Life?Cycle  Inventories Using Hybrid Approaches.  EEA 2006] Emission Inventory Guidebook; Activities 080501?I: National Lighting Inventory and  Energy Consumption 

Chester, Mikhail V

2008-01-01T23:59:59.000Z

49

Multicentury Changes to the Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model  

Science Conference Proceedings (OSTI)

A coupled climate and carbon (CO2) cycle model is used to investigate the global climate and carbon cycle changes out to the year 2300 that would occur if CO2 emissions from all the currently estimated fossil fuel resources were released to the ...

G. Bala; K. Caldeira; A. Mirin; M. Wickett; C. Delire

2005-11-01T23:59:59.000Z

50

Control system for single shaft combined cycle gas and steam turbine unit  

SciTech Connect

This patent describes a method for starting and controlling a combined cycle turbine of the type having a gas turbine with a fuel flow control valve and a steam turbine with at least one steam control valve both disposed on a single shaft and having a heat recovery steam generator heated by the gas turbine and connected to supply steam to the steam control valve, the combined cycle turbine having a unified control system and driving a load, and also having an auxiliary steam source connected to the steam control valve. It comprises controlling of steam from the auxiliary steam source with the steam control valve to crank the combined cycle turbine for starting, initiating and controlling fuel flow to the gas turbine with the fuel flow control valve and initiating combustion, controlling initial acceleration of the combined cycle turbine with the steam control valve on auxiliary steam, coordinating control of the combined cycle turbine by the steam control valve and the fuel control valve with the unified control system, transferring acceleration control during a smooth acceleration phase of the combined cycle turbine by the steam control valve and the fuel control valve with the unified control system, transferring acceleration control during a smooth acceleration phase of the combined cycle turbine to the fuel flow control valve and gradually reducing the opening of the steam control valve to a minimum value when the turbine reaches rated speed.

Moore, J.H.; Kure-Jensen, J.; Rowen, W.I.

1991-08-27T23:59:59.000Z

51

Model-Based Drought Indices over the United States  

Science Conference Proceedings (OSTI)

Drought indices derived from the North American Land Data Assimilation System (NLDAS) Variable Infiltration Capacity (VIC) and Noah models from 1950 to 2000 are intercompared and evaluated for their ability to classify drought across the United ...

Kingtse C. Mo

2008-12-01T23:59:59.000Z

52

A Hybrid Model for Hydroturbine Generating Unit Trend Analysis  

Science Conference Proceedings (OSTI)

According to the nonlinear and nonstationary characteristics of hydroelectricity systems, an hybrid prediction model based on wavelet transform and support vector machines is proposed in this paper for the trend analysis of hydroturbine generating unit ...

Min Zou; Jianzhong Zhou; Zhong Liu; Liangliang Zhan

2007-08-01T23:59:59.000Z

53

Community Radiative Transfer Model for Stratospheric Sounding Unit  

Science Conference Proceedings (OSTI)

To better use the Stratospheric Sounding Unit (SSU) data for reanalysis and climate studies, issues associated with the fast radiative transfer (RT) model for SSU have recently been revisited and the results have been implemented into the ...

Yong Chen; Yong Han; Quanhua Liu; Paul Van Delst; Fuzhong Weng

2011-06-01T23:59:59.000Z

54

Climate–Carbon Cycle Feedback Analysis: Results from the C4MIP Model Intercomparison  

Science Conference Proceedings (OSTI)

Eleven coupled climate–carbon cycle models used a common protocol to study the coupling between climate change and the carbon cycle. The models were forced by historical emissions and the Intergovernmental Panel on Climate Change (IPCC) Special ...

P. Friedlingstein; P. Cox; R. Betts; L. Bopp; W. von Bloh; V. Brovkin; P. Cadule; S. Doney; M. Eby; I. Fung; G. Bala; J. John; C. Jones; F. Joos; T. Kato; M. Kawamiya; W. Knorr; K. Lindsay; H. D. Matthews; T. Raddatz; P. Rayner; C. Reick; E. Roeckner; K.-G. Schnitzler; R. Schnur; K. Strassmann; A. J. Weaver; C. Yoshikawa; N. Zeng

2006-07-01T23:59:59.000Z

55

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

56

The FIT Model - Fuel-cycle Integration and Tradeoffs  

Science Conference Proceedings (OSTI)

All mass streams from fuel separation and fabrication are products that must meet some set of product criteria – fuel feedstock impurity limits, waste acceptance criteria (WAC), material storage (if any), or recycle material purity requirements such as zirconium for cladding or lanthanides for industrial use. These must be considered in a systematic and comprehensive way. The FIT model and the “system losses study” team that developed it [Shropshire2009, Piet2010] are an initial step by the FCR&D program toward a global analysis that accounts for the requirements and capabilities of each component, as well as major material flows within an integrated fuel cycle. This will help the program identify near-term R&D needs and set longer-term goals. The question originally posed to the “system losses study” was the cost of separation, fuel fabrication, waste management, etc. versus the separation efficiency. In other words, are the costs associated with marginal reductions in separations losses (or improvements in product recovery) justified by the gains in the performance of other systems? We have learned that that is the wrong question. The right question is: how does one adjust the compositions and quantities of all mass streams, given uncertain product criteria, to balance competing objectives including cost? FIT is a method to analyze different fuel cycles using common bases to determine how chemical performance changes in one part of a fuel cycle (say used fuel cooling times or separation efficiencies) affect other parts of the fuel cycle. FIT estimates impurities in fuel and waste via a rough estimate of physics and mass balance for a set of technologies. If feasibility is an issue for a set, as it is for “minimum fuel treatment” approaches such as melt refining and AIROX, it can help to make an estimate of how performances would have to change to achieve feasibility.

Steven J. Piet; Nick R. Soelberg; Samuel E. Bays; Candido Pereira; Layne F. Pincock; Eric L. Shaber; Meliisa C Teague; Gregory M Teske; Kurt G Vedros

2010-09-01T23:59:59.000Z

57

Development of a plant-wide dynamic model of an integrated gasification combined cycle (IGCC) plant  

Science Conference Proceedings (OSTI)

In this presentation, development of a plant-wide dynamic model of an advanced Integrated Gasification Combined Cycle (IGCC) plant with CO2 capture will be discussed. The IGCC reference plant generates 640 MWe of net power using Illinois No.6 coal as the feed. The plant includes an entrained, downflow, General Electric Energy (GEE) gasifier with a radiant syngas cooler (RSC), a two-stage water gas shift (WGS) conversion process, and two advanced 'F' class combustion turbines partially integrated with an elevated-pressure air separation unit (ASU). A subcritical steam cycle is considered for heat recovery steam generation. Syngas is selectively cleaned by a SELEXOL acid gas removal (AGR) process. Sulfur is recovered using a two-train Claus unit with tail gas recycle to the AGR. A multistage intercooled compressor is used for compressing CO2 to the pressure required for sequestration. Using Illinois No.6 coal, the reference plant generates 640 MWe of net power. The plant-wide steady-state and dynamic IGCC simulations have been generated using the Aspen Plus{reg_sign} and Aspen Plus Dynamics{reg_sign} process simulators, respectively. The model is generated based on the Case 2 IGCC configuration detailed in the study available in the NETL website1. The GEE gasifier is represented with a restricted equilibrium reactor model where the temperature approach to equilibrium for individual reactions can be modified based on the experimental data. In this radiant-only configuration, the syngas from the Radiant Syngas Cooler (RSC) is quenched in a scrubber. The blackwater from the scrubber bottom is further cleaned in the blackwater treatment plant. The cleaned water is returned back to the scrubber and also used for slurry preparation. The acid gas from the sour water stripper (SWS) is sent to the Claus plant. The syngas from the scrubber passes through a sour shift process. The WGS reactors are modeled as adiabatic plug flow reactors with rigorous kinetics based on the mid-life activity of the shift-catalyst. The SELEXOL unit consists of the H2S and CO2 absorbers that are designed to meet the stringent environmental limits and requirements of other associated units. The model also considers the stripper for recovering H2S that is sent as a feed to a split-flow Claus unit. The tail gas from the Claus unit is recycled to the SELEXOL unit. The cleaned syngas is sent to the GE 7FB gas turbine. This turbine is modeled as per published data in the literature. Diluent N2 is used from the elevated-pressure ASU for reducing the NOx formation. The heat recovery steam generator (HRSG) is modeled by considering generation of high-pressure, intermediate-pressure, and low-pressure steam. All of the vessels, reactors, heat exchangers, and the columns have been sized. The basic IGCC process control structure has been synthesized by standard guidelines and existing practices. The steady-state simulation is solved in sequential-modular mode in Aspen Plus{reg_sign} and consists of more than 300 unit operations, 33 design specs, and 16 calculator blocks. The equation-oriented dynamic simulation consists of more than 100,000 equations solved using a multi-step Gear's integrator in Aspen Plus Dynamics{reg_sign}. The challenges faced in solving the dynamic model and key transient results from this dynamic model will also be discussed.

Bhattacharyya, D.; Turton, R.; Zitney, S.

2009-01-01T23:59:59.000Z

58

Modeling the Q-cycle mechanism of transmembrane energy conversion  

E-Print Network (OSTI)

The Q-cycle mechanism plays an important role in the conversion of the redox energy into the energy of the proton electrochemical gradient across the biomembrane. The bifurcated electron transfer reaction, which is built into this mechanism, recycles one electron, thus, allowing to translocate two protons per one electron moving to the high-potential redox chain. We study a kinetic model of the Q-cycle mechanism in an artificial system which mimics the bf complex of plants and cyanobacteria in the regime of ferredoxin-dependent cyclic electron flow. Using methods of condensed matter physics, we derive a set of master equations and describe a time sequence of electron and proton transfer reactions in the complex. We find energetic conditions when the bifurcation of the electron pathways at the positive side of the membrane occurs naturally, without any additional gates. For reasonable parameter values, we show that this system is able to translocate more than 1.8 protons, on average, per one electron, with a thermodynamic efficiency of the order of 32% or higher.

Anatoly Yu. Smirnov; Franco Nori

2011-06-29T23:59:59.000Z

59

Modeling the Q-cycle mechanism of transmembrane energy conversion  

E-Print Network (OSTI)

The Q-cycle mechanism plays an important role in the conversion of the redox energy into the energy of the proton electrochemical gradient across the biomembrane. The bifurcated electron transfer reaction, which is built into this mechanism, recycles one electron, thus, allowing to translocate two protons per one electron moving to the high-potential redox chain. We study a kinetic model of the Q-cycle mechanism in an artificial system which mimics the bf complex of plants and cyanobacteria in the regime of ferredoxin-dependent cyclic electron flow. Using methods of condensed matter physics, we derive a set of master equations and describe a time sequence of electron and proton transfer reactions in the complex. We find energetic conditions when the bifurcation of the electron pathways at the positive side of the membrane occurs naturally, without any additional gates. For reasonable parameter values, we show that this system is able to translocate more than 1.8 protons, on average, per one electron, with a t...

Smirnov, Anatoly Yu

2011-01-01T23:59:59.000Z

60

Compressor and Turbine Models of Brayton Units for Space Nuclear Power Systems  

SciTech Connect

Closed Brayton Cycles with centrifugal flow, single-shaft turbo-machines are being considered, with gas cooled nuclear reactors, to provide 10's to 100's of electrical power to support future space exploration missions and Lunar and Mars outposts. Such power system analysis is typically based on the cycle thermodynamics, for given operating pressures and temperatures and assumed polytropic efficiencies of the compressor and turbine of the Brayton energy conversion units. Thus the analysis results not suitable for modeling operation transients such as startup and changes in the electric load. To simulate these transients, accurate models of the turbine and compressor in the Brayton rotating unit, which calculate the changes in the compressor and turbine efficiencies with system operation are needed. This paper presents flow models that account for the design and dimensions of the compressor impeller and diffuser, and the turbine stator and rotor blades. These models calculate the various enthalpy losses and the polytropic efficiencies along with the pressure ratios of the turbine and compressor. The predictions of these models compare well with reported performance data of actual hardware. In addition, the results of a parametric analysis to map the operations of the compressor and turbine, as functions of the rotating shaft speed and inlet Mach number of the gas working fluid, are presented and discussed. The analysis used a binary mixture of He-Xe with a molecular weight of 40 g/mole as the working fluid.

Gallo, Bruno M.; El-Genk, Mohamed S.; Tournier, Jean-Michel [Institute for Space and Nuclear Power Studies, University of New Mexico, Albuquerque, NM, 87131 (United States); Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM, 87131 (United States)

2007-01-30T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Determination of the proper operating range for the CAFCA IIB fuel cycle model  

E-Print Network (OSTI)

The fuel cycle simulation tool, CAFCA II was previously modified to produce the most recent version, CAFCA IIB. The code tracks the mass distribution of transuranics in the fuel cycle in one model and also projects costs ...

Warburton, Jamie (Jamie L.)

2007-01-01T23:59:59.000Z

62

Attachment A: Modeling in Support of Additional Two-Unit Operating...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Attachment A: Modeling in Support of Additional Two-Unit Operating Configurations Attachment A: Modeling in Support of Additional Two-Unit Operating Configurations Docket No....

63

Autonomous Units to Model Interacting Sequential and Parallel Processes  

E-Print Network (OSTI)

In this paper, we introduce the notion of a community of autonomous units as a rulebased and graph-transformational device to model processes that run interactively but independently of each other in a common environment. The main components of an autonomous unit are a set of rules, a control condition, and a goal. Every autonomous unit transforms graphs by applying its rules so that the control condition is satisfied. If the goal is reached the resulting transformation process is successful. A community contains a set of autonomous units, an initial environment specification, and an overall goal. In every transformation process of a community the autonomous units interact via their common environment. As an example, the game Ludo is modeled as a community of selfcontrolled players who interact on a common board. The emphasis of the presented approach is laid on the study of the formal semantics of a community as a whole and of each of its member units separately. In particular, a sequential as well as a parallel semantics is introduced, and communities with parallel semantics are compared with Petri nets, cellular automata, and multiagent systems.

Karsten Hölscher; Hans-Jörg Kreowski; Sabine Kuske

2009-01-01T23:59:59.000Z

64

Modeling Behavior Cycles as a Value System for Developmental Robots  

Science Conference Proceedings (OSTI)

The behavior of natural systems is governed by rhythmic behavior cycles at the biological, cognitive, and social levels. These cycles permit natural organisms to adapt their behavior to their environment for survival, behavioral efficiency, or evolutionary ... Keywords: SART networks, behavior cycles, developmental robotics, motivated reinforcement learning, neural networks

Kathryn E. Merrick

2010-06-01T23:59:59.000Z

65

The Precipitation Life Cycle of Mesoscale Convective Complexes over the Central United States  

Science Conference Proceedings (OSTI)

The mesoscale convective complex (MCC) is a common and particularly well-organized class of meso-&? scale storm systems over the central United States. As observed by infrared (IR) satellite, the typical MCC's 10–12 h evolution displays a fairly ...

Ray L. McAnelly; William R. Cotton

1989-04-01T23:59:59.000Z

66

Model Predictive Control of Integrated Gasification Combined Cycle Power Plants  

SciTech Connect

The primary project objectives were to understand how the process design of an integrated gasification combined cycle (IGCC) power plant affects the dynamic operability and controllability of the process. Steady-state and dynamic simulation models were developed to predict the process behavior during typical transients that occur in plant operation. Advanced control strategies were developed to improve the ability of the process to follow changes in the power load demand, and to improve performance during transitions between power levels. Another objective of the proposed work was to educate graduate and undergraduate students in the application of process systems and control to coal technology. Educational materials were developed for use in engineering courses to further broaden this exposure to many students. ASPENTECH software was used to perform steady-state and dynamic simulations of an IGCC power plant. Linear systems analysis techniques were used to assess the steady-state and dynamic operability of the power plant under various plant operating conditions. Model predictive control (MPC) strategies were developed to improve the dynamic operation of the power plants. MATLAB and SIMULINK software were used for systems analysis and control system design, and the SIMULINK functionality in ASPEN DYNAMICS was used to test the control strategies on the simulated process. Project funds were used to support a Ph.D. student to receive education and training in coal technology and the application of modeling and simulation techniques.

B. Wayne Bequette; Priyadarshi Mahapatra

2010-08-31T23:59:59.000Z

67

A Stochastic Unit Commitment Model for Integrating Renewable Supply  

E-Print Network (OSTI)

A Stochastic Unit Commitment Model for Integrating Renewable Supply and Demand Response Anthony from the large-scale integration of renewable energy sources and deferrable demand in power systems. We- sorbing the uncertainty and variability associated with renewable supply: centralized co

Oren, Shmuel S.

68

Development and applications of GREET 2.7 -- The Transportation Vehicle-CycleModel.  

DOE Green Energy (OSTI)

Argonne National Laboratory has developed a vehicle-cycle module for the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model. The fuel-cycle GREET model has been cited extensively and contains data on fuel cycles and vehicle operations. The vehicle-cycle model evaluates the energy and emission effects associated with vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling. With the addition of the vehicle-cycle module, the GREET model now provides a comprehensive, lifecycle-based approach to compare the energy use and emissions of conventional and advanced vehicle technologies (e.g., hybrid electric vehicles and fuel cell vehicles). This report details the development and application of the GREET 2.7 model. The current model includes six vehicles--a conventional material and a lightweight material version of a mid-size passenger car with the following powertrain systems: internal combustion engine, internal combustion engine with hybrid configuration, and fuel cell with hybrid configuration. The model calculates the energy use and emissions that are required for vehicle component production; battery production; fluid production and use; and vehicle assembly, disposal, and recycling. This report also presents vehicle-cycle modeling results. In order to put these results in a broad perspective, the fuel-cycle model (GREET 1.7) was used in conjunction with the vehicle-cycle model (GREET 2.7) to estimate total energy-cycle results.

Burnham, A.; Wang, M. Q.; Wu, Y.

2006-12-20T23:59:59.000Z

69

The Role of the Western Boundary in the ENSO Cycle: Experiments with Coupled Models  

Science Conference Proceedings (OSTI)

Coupled models of the Pacific ocean–atmosphere system have been shown to produce oscillations in the model coupled system that resemble the observed El Niño–Southern Oscillation (ENSO) cycle in many respects. The tendency for the coupled models ...

Nicholas E. Graham; Warren B. White

1990-12-01T23:59:59.000Z

70

A Heuristic Model of the Dansgaard-Oeschger Cycles: Description, Results, and Sensitivity Studies: Part I  

Science Conference Proceedings (OSTI)

We present a simple model for studying the D-O cycles of the last glacial period, based on the Dokken Et Al Hypothesis for D-O Cycles. The model is a column model representing the Nordic Seas, and is composed of ocean boxes stacked below a one-...

Hansi A. Singh; David S. Battisti; Cecilia M. Bitz

71

Experiences with early life-cycle performance modeling for architecture assessment  

Science Conference Proceedings (OSTI)

In this paper we describe our preliminary experiences of a performance modeling "Blending" approach for early life-cycle architecture assessment and risk mitigation in a large enterprise integration project. The goal was to use performance modeling to ... Keywords: blended performance modeling, early life-cycle risk mitigation

Paul C. Brebner

2012-06-01T23:59:59.000Z

72

Dynamic Mercury Cycling Model Version 3.0 (D-MCM)  

Science Conference Proceedings (OSTI)

The Dynamic Mercury Cycling Model (D-MCM) predicts the cycling and fate of the major forms of mercury in lakes. The Dynamic Mercury Cycling Model (D-MCM) is a Windowsbased simulation model for personal computers. It predicts the cycling and fate of the major forms of mercury in lakes, including methylmercury, Hg(II), and elemental mercury. D-MCM is a time-dependent mechanistic model, designed to consider the most important physical, chemical and biological factors affecting fish mercury concentrations in...

2009-12-09T23:59:59.000Z

73

Parallel Simulation for a Fish Schooling Model on a General-Purpose Graphics Processing Unit  

E-Print Network (OSTI)

Model on a General-Purpose Graphics Processing Unit Hong LiThe current generation of graphics processing units is well-we will describe how a Graphics Pro- cessor Unit (GPU) can

Li, Hong; Kolpas, Allison; Petzold, Linda; Moehlis, J

2009-01-01T23:59:59.000Z

74

Design and Validation of an Offline Oceanic Tracer Transport Model for a Carbon Cycle Study  

Science Conference Proceedings (OSTI)

An offline passive tracer transport model with self-operating diagnostic-mode vertical mixing and horizontal diffusion parameterizations is used with assimilated ocean currents to find the chlorofluorocarbon (CFC-11) cycle in oceans. This model ...

Vinu Valsala; Shamil Maksyutov; Ikeda Motoyoshi

2008-06-01T23:59:59.000Z

75

The Tropical Water and Energy Cycles in a Cumulus Ensemble Model. Part I: Equilibrium Climate  

Science Conference Proceedings (OSTI)

A cumulus ensemble model is used to study the tropical water and energy cycles and their role in the climate system. The model includes cloud dynamics, radiative processes, and microphysics that incorporate all important production and conversion ...

C. H. Sui; K. M. Lau; W. K. Tao; J. Simpson

1994-03-01T23:59:59.000Z

76

PRE-SW Dynamic Mercury Cycling Model (D-MCM)Version 4.0, Beta  

Science Conference Proceedings (OSTI)

The Dynamic Mercury Cycling Model (D-MCM) is a Windows™ based simulation model for personal computers. It predicts mercury cycling and bioaccumulation in aquatic systems.  Mercury forms include methylmercury, Hg(II), and elemental mercury. D-MCM is a time-dependent mechanistic model that can be applied deterministically or probabilistically. Version 4.0 is a major update to D-MCM.   The model can be applied in 1,2, and 3 dimensional applications for lakes, rivers, estuaries, ...

2013-09-17T23:59:59.000Z

77

A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling  

E-Print Network (OSTI)

Under typical PEM fuel cell operating conditions, part of membrane electrode assembly is subjected to humidity cycling due to variation of inlet gas RH and/or flow rate. Cyclic membrane hydration/dehydration would cause cyclic swelling/shrinking of the unconstrained membrane. In a constrained membrane, it causes cyclic stress resulting in mechanical failure in the area adjacent to the gas inlet. A mathematical modeling framework for prediction of the lifetime of a PEM FC membrane subjected to hydration cycling is developed in this paper. The model predicts membrane lifetime as a function of RH cycling amplitude and membrane mechanical properties. The modeling framework consists of three model components: a fuel cell RH distribution model, a hydration/dehydration induced stress model that predicts stress distribution in the membrane, and a damage accrual model that predicts membrane life-time. Short descriptions of the model components along with overall framework are presented in the paper. The model was used...

Burlatsky, S F; O'Neill, J; Atrazhev, V V; Varyukhin, A N; Dmitriev, D V; Erikhman, N S

2013-01-01T23:59:59.000Z

78

MODELING AND CONTROL OF A O2/CO2 GAS TURBINE CYCLE FOR CO2 CAPTURE  

E-Print Network (OSTI)

MODELING AND CONTROL OF A O2/CO2 GAS TURBINE CYCLE FOR CO2 CAPTURE Lars Imsland Dagfinn Snarheim and control of a semi-closed O2/CO2 gas turbine cycle for CO2 capture. In the first part the process predictive control, Gas turbines, CO2 capture 1. INTRODUCTION Gas turbines are widely used for power

Foss, Bjarne A.

79

Dynamic modeling and multivariable control of organic Rankine cycles in waste heat utilizing processes  

Science Conference Proceedings (OSTI)

In this paper, the dynamics of organic Rankine cycles (ORCs) in waste heat utilizing processes is investigated, and the physical model of a 100 kW waste heat utilizing process is established. In order to achieve both transient performance and steady-state ... Keywords: Linear quadratic regulator, Organic Rankine cycles, Process control

Jianhua Zhang; Wenfang Zhang; Guolian Hou; Fang Fang

2012-09-01T23:59:59.000Z

80

Evaluating the Carbon Cycle of a Coupled Atmosphere-Biosphere Model  

SciTech Connect

We investigate how well a coupled biosphere-atmosphere model, CCM3-IBIS, can simulate the functioning of the terrestrial biosphere and the carbon cycling through it. The simulated climate is compared to observations, while the vegetation cover and the carbon cycle are compared to an offline version of the biosphere model IBIS forced with observed climatic variables. The simulated climate presents some local biases that strongly affect the vegetation (e.g., a misrepresentation of the African monsoon). Compared to the offline model, the coupled model simulates well the globally averaged carbon fluxes and vegetation pools. The zonal mean carbon fluxes and the zonal mean seasonal cycle are also well represented except between 0{sup o} and 20{sup o}N due to the misrepresentation of the African monsoon. These results suggest that, despite regional biases in climate and ecosystem simulations, this coupled atmosphere-biosphere model can be used to explore geographic and temporal variations in the global carbon cycle.

Delire, C; Foley, J A; Thompson, S

2002-08-21T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Climate–Carbon Cycle Model Response to Freshwater Discharge into the North Atlantic  

Science Conference Proceedings (OSTI)

The response of a coupled climate–carbon cycle model to discharge of freshwater into the North Atlantic is investigated with regard to cold reversals caused by meltwater from northern continental ice sheets such as the Younger Dryas during the ...

Atsushi Obata

2007-12-01T23:59:59.000Z

82

Model Bias in a Continuously Cycled Assimilation System and Its Influence on Convection-Permitting Forecasts  

Science Conference Proceedings (OSTI)

During the spring 2011 season, a real-time continuously cycled ensemble data assimilation system using the Advanced Research version of the Weather Research and Forecasting Model (WRF) coupled with the Data Assimilation Research Testbed toolkit ...

Glen S. Romine; Craig S. Schwartz; Chris Snyder; Jeff L. Anderson; Morris L. Weisman

2013-04-01T23:59:59.000Z

83

The Operational Eta Model Precipitation and Surface Hydrologic Cycle of the Columbia and Colorado Basins  

Science Conference Proceedings (OSTI)

The surface hydrology of the United States’ western basins is investigated using the National Centers for Environmental Prediction operational Eta Model forecasts. During recent years the model has been subject to changes and upgrades that ...

Yan Luo; Ernesto H. Berbery; Kenneth E. Mitchell

2005-08-01T23:59:59.000Z

84

Modeling the Seasonal Cycle of the Upper Ocean  

Science Conference Proceedings (OSTI)

The parameterization of the turbulence used in one-dimensional oceanic mixed layer models is briefly reviewed, focusing on the long-term response of these models. Particular attention is directed towards the parameterization of turbulent ...

Philippe Gaspar

1988-02-01T23:59:59.000Z

85

Nonlinear model predictive control for dosing daily anticancer agents using a novel saturating-rate cell-cycle model  

Science Conference Proceedings (OSTI)

A nonlinear model predictive control (NMPC) algorithm was developed to dose the chemotherapeutic agent tamoxifen based on a novel saturating-rate, cell-cycle model (SCM). Using daily tumor measurements, the algorithm decreased tumor volume along a specified ... Keywords: Biomedical systems, Cancer, Nonlinear model, Nonlinear model predictive control, Pharmacodynamics, Pharmacokinetics

Jeffry A. Florian, Jr.; Julie L. Eiseman; Robert S. Parker

2008-03-01T23:59:59.000Z

86

Heat transfer research and power cycle transient modeling  

DOE Green Energy (OSTI)

Fine axial flutes enhance heat transfer in vertical shell-and-tube exchangers with water inside the tubes and ammonia evaporating or condensing in layer flow on the shell side. Single-tube experiments with R-11 and ammonia indicate local shell-side coefficients 3 to 5 times those for corresponding smooth tubes. Single-tube experiments with water indicate that at moderate velocities the tube-side coefficients are enhanced by a factor equal to the ratio of fluted-to-smooth surface areas while the fluid friction is similarly increased. The experimental data are transformed into mean individual coefficients for ammonia and water. Overall coefficients for a particular case are presented to illustrate the efficacy of enhancement by flutes on one or both sides of the heat transfer surface. Means are described for using emerging data to predict the static and dynamic behavior of the power cycle and the interactions of components throughout the complete power plant.

Rothfus, R.R.; Neuman, C.P.

1977-03-23T23:59:59.000Z

87

Effects of soot-induced snow albedo change on snowpack and hydrological cycle in western United States based on Weather Research and Forecasting chemistry and regional climate simulations  

Science Conference Proceedings (OSTI)

Radiative forcing induced by soot on snow is a major anthropogenic forcing affecting the global climate. However, it is uncertain how the soot-induced snow albedo perturbation affects regional snowpack and the hydrological cycle. In this study we simulated the deposition of soot aerosol on snow and investigated the resulting impact on snowpack and the surface water budget in the western United States. A yearlong simulation was performed using the chemistry version of the Weather Research and Forecasting model (WRF-Chem) to determine an annual budget of soot deposition, followed by two regional climate simulations using WRF in meteorology-only mode, with and without the soot-induced snow albedo perturbations. The chemistry simulation shows large spatial variability in soot deposition that reflects the localized emissions and the influence of the complex terrain. The soot-induced snow albedo perturbations increase the net solar radiation flux at the surface during late winter to early spring, increase the surface air temperature, reduce snow water equivalent amount, and lead to reduced snow accumulation and less spring snowmelt. These effects are stronger over the central Rockies and southern Alberta, where soot deposition and snowpack overlap the most. The indirect forcing of soot accelerates snowmelt and alters stream flows, including a trend toward earlier melt dates in the western United States. The soot-induced albedo reduction initiates a positive feedback process whereby dirty snow absorbs more solar radiation, heating the surface and warming the air. This warming causes reduced snow depth and fraction, which further reduces the regional surface albedo for the snow covered regions. Our simulations indicate that the change of maximum snow albedo induced by soot on snow contributes to 60% of the net albedo reduction over the central Rockies. Snowpack reduction accounts for the additional 40%.

Qian, Yun; Gustafson, William I.; Leung, Lai-Yung R.; Ghan, Steven J.

2009-02-14T23:59:59.000Z

88

HOW FAR CAN MINIMAL MODELS EXPLAIN THE SOLAR CYCLE?  

Science Conference Proceedings (OSTI)

A physically consistent model of magnetic field generation by convection in a rotating spherical shell with a minimum of parameters is applied to the Sun. Despite its unrealistic features the model exhibits a number of properties resembling those observed on the Sun. The model suggests the importance of the non-axisymmetric m = 1 or m = 2 component of the magnetic field for the large-scale solar dynamo.

Simitev, R. D. [School of Mathematics and Statistics, University of Glasgow, Glasgow, G12 8QW (United Kingdom); Busse, F. H. [Institute of Physics, University of Bayreuth, 95440 Bayreuth (Germany)

2012-04-10T23:59:59.000Z

89

User Guide for VISION 3.4.7 (Verifiable Fuel Cycle Simulation) Model  

SciTech Connect

The purpose of this document is to provide a guide for using the current version of the Verifiable Fuel Cycle Simulation (VISION) model. This is a complex model with many parameters and options; the user is strongly encouraged to read this user guide before attempting to run the model. This model is an R&D work in progress and may contain errors and omissions. It is based upon numerous assumptions. This model is intended to assist in evaluating 'what if' scenarios and in comparing fuel, reactor, and fuel processing alternatives at a systems level. The model is not intended as a tool for process flow and design modeling of specific facilities nor for tracking individual units of fuel or other material through the system. The model is intended to examine the interactions among the components of a fuel system as a function of time varying system parameters; this model represents a dynamic rather than steady-state approximation of the nuclear fuel system. VISION models the nuclear cycle at the system level, not individual facilities, e.g., 'reactor types' not individual reactors and 'separation types' not individual separation plants. Natural uranium can be enriched, which produces enriched uranium, which goes into fuel fabrication, and depleted uranium (DU), which goes into storage. Fuel is transformed (transmuted) in reactors and then goes into a storage buffer. Used fuel can be pulled from storage into either separation or disposal. If sent to separations, fuel is transformed (partitioned) into fuel products, recovered uranium, and various categories of waste. Recycled material is stored until used by its assigned reactor type. VISION is comprised of several Microsoft Excel input files, a Powersim Studio core, and several Microsoft Excel output files. All must be co-located in the same folder on a PC to function. You must use Powersim Studio 8 or better. We have tested VISION with the Studio 8 Expert, Executive, and Education versions. The Expert and Education versions work with the number of reactor types of 3 or less. For more reactor types, the Executive version is currently required. The input files are Excel2003 format (xls). The output files are macro-enabled Excel2007 format (xlsm). VISION 3.4 was designed with more flexibility than previous versions, which were structured for only three reactor types - LWRs that can use only uranium oxide (UOX) fuel, LWRs that can use multiple fuel types (LWR MF), and fast reactors. One could not have, for example, two types of fast reactors concurrently. The new version allows 10 reactor types and any user-defined uranium-plutonium fuel is allowed. (Thorium-based fuels can be input but several features of the model would not work.) The user identifies (by year) the primary fuel to be used for each reactor type. The user can identify for each primary fuel a contingent fuel to use if the primary fuel is not available, e.g., a reactor designated as using mixed oxide fuel (MOX) would have UOX as the contingent fuel. Another example is that a fast reactor using recycled transuranic (TRU) material can be designated as either having or not having appropriately enriched uranium oxide as a contingent fuel. Because of the need to study evolution in recycling and separation strategies, the user can now select the recycling strategy and separation technology, by year.

Jacob J. Jacobson; Robert F. Jeffers; Gretchen E. Matthern; Steven J. Piet; Wendell D. Hintze

2011-07-01T23:59:59.000Z

90

Micro-CHP Modeling and Simulation using Thermodynamic Cycles.  

E-Print Network (OSTI)

??This thesis discusses the thermoeconomic modeling and simulation of micro-CHP systems powered by various prime movers. Micro Cooling, Heating, and Power (micro-CHP) is becoming an… (more)

Moran, Alan Mark

2006-01-01T23:59:59.000Z

91

GREET 1.0 -- Transportation fuel cycles model: Methodology and use  

DOE Green Energy (OSTI)

This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel-cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, Co, NOx, SOx, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied petroleum gas, methanol, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydropower, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; and landfill gases to methanol. This report presents fuel-cycle energy use and emissions for a 2000 model-year car powered by each of the fuels that are produced from the primary energy sources considered in the study.

Wang, M.Q.

1996-06-01T23:59:59.000Z

92

Observation and Modeling of the Solar-Cycle Variation of the Meridional Flow  

E-Print Network (OSTI)

We present independent observations of the solar-cycle variation of flows near the solar surface and at a depth of about 60 Mm, in the latitude range $\\pm45^\\circ$. We show that the time-varying components of the meridional flow at these two depths have opposite sign, while the time-varying components of the zonal flow are in phase. This is in agreement with previous results. We then investigate whether the observations are consistent with a theoretical model of solar-cycle dependent meridional circulation based on a flux-transport dynamo combined with a geostrophic flow caused by increased radiative loss in the active region belt (the only existing quantitative model). We find that the model and the data are in qualitative agreement, although the amplitude of the solar-cycle variation of the meridional flow at 60 Mm is underestimated by the model.

Gizon, L

2008-01-01T23:59:59.000Z

93

Observation and Modeling of the Solar-Cycle Variation of the Meridional Flow  

E-Print Network (OSTI)

We present independent observations of the solar-cycle variation of flows near the solar surface and at a depth of about 60 Mm, in the latitude range $\\pm45^\\circ$. We show that the time-varying components of the meridional flow at these two depths have opposite sign, while the time-varying components of the zonal flow are in phase. This is in agreement with previous results. We then investigate whether the observations are consistent with a theoretical model of solar-cycle dependent meridional circulation based on a flux-transport dynamo combined with a geostrophic flow caused by increased radiative loss in the active region belt (the only existing quantitative model). We find that the model and the data are in qualitative agreement, although the amplitude of the solar-cycle variation of the meridional flow at 60 Mm is underestimated by the model.

L. Gizon; M. Rempel

2008-03-06T23:59:59.000Z

94

Model reduction and physical understanding of slowly oscillating processes : the circadian cycle.  

Science Conference Proceedings (OSTI)

A differential system that models the circadian rhythm in Drosophila is analyzed with the computational singular perturbation (CSP) algorithm. Reduced nonstiff models of prespecified accuracy are constructed, the form and size of which are time-dependent. When compared with conventional asymptotic analysis, CSP exhibits superior performance in constructing reduced models, since it can algorithmically identify and apply all the required order of magnitude estimates and algebraic manipulations. A similar performance is demonstrated by CSP in generating data that allow for the acquisition of physical understanding. It is shown that the processes driving the circadian cycle are (i) mRNA translation into monomer protein, and monomer protein destruction by phosphorylation and degradation (along the largest portion of the cycle); and (ii) mRNA synthesis (along a short portion of the cycle). These are slow processes. Their action in driving the cycle is allowed by the equilibration of the fastest processes; (1) the monomer dimerization with the dimer dissociation (along the largest portion of the cycle); and (2) the net production of monomer+dimmer proteins with that of mRNA (along the short portion of the cycle). Additional results (regarding the time scales of the established equilibria, their origin, the rate limiting steps, the couplings among the variables, etc.) highlight the utility of CSP for automated identification of the important underlying dynamical features, otherwise accessible only for simple systems whose various suitable simplifications can easily be recognized.

Goussis, Dimitris A. (Ploutonos 7, Palaio Faliro, Greece); Najm, Habib N.

2006-01-01T23:59:59.000Z

95

Application of RBF-type ARX Modeling and Control to Gas Turbine Combined Cycle SCR Systems  

E-Print Network (OSTI)

Application of RBF-type ARX Modeling and Control to Gas Turbine Combined Cycle SCR Systems Y, nonlinear model-based predictive control, energy saving. 1. INTRODUCTION In Japan, GTCC(Gas Turbine Combined gas-firing GTCC power plant is most effective in terms of thermal efficiency and lower CO2 energy

Ozaki, Tohru

96

Sensor placement algorithm development to maximize the efficiency of acid gas removal unit for integrated gasification combined cycle (IGCC) power plant with CO{sub 2} capture  

Science Conference Proceedings (OSTI)

Future integrated gasification combined cycle (IGCC) power plants with CO{sub 2} capture will face stricter operational and environmental constraints. Accurate values of relevant states/outputs/disturbances are needed to satisfy these constraints and to maximize the operational efficiency. Unfortunately, a number of these process variables cannot be measured while a number of them can be measured, but have low precision, reliability, or signal-to-noise ratio. In this work, a sensor placement (SP) algorithm is developed for optimal selection of sensor location, number, and type that can maximize the plant efficiency and result in a desired precision of the relevant measured/unmeasured states. In this work, an SP algorithm is developed for an selective, dual-stage Selexol-based acid gas removal (AGR) unit for an IGCC plant with pre-combustion CO{sub 2} capture. A comprehensive nonlinear dynamic model of the AGR unit is developed in Aspen Plus Dynamics® (APD) and used to generate a linear state-space model that is used in the SP algorithm. The SP algorithm is developed with the assumption that an optimal Kalman filter will be implemented in the plant for state and disturbance estimation. The algorithm is developed assuming steady-state Kalman filtering and steady-state operation of the plant. The control system is considered to operate based on the estimated states and thereby, captures the effects of the SP algorithm on the overall plant efficiency. The optimization problem is solved by Genetic Algorithm (GA) considering both linear and nonlinear equality and inequality constraints. Due to the very large number of candidate sets available for sensor placement and because of the long time that it takes to solve the constrained optimization problem that includes more than 1000 states, solution of this problem is computationally expensive. For reducing the computation time, parallel computing is performed using the Distributed Computing Server (DCS®) and the Parallel Computing® toolbox from Mathworks®. In this presentation, we will share our experience in setting up parallel computing using GA in the MATLAB® environment and present the overall approach for achieving higher computational efficiency in this framework.

Paul, P.; Bhattacharyya, D.; Turton, R.; Zitney, S.

2012-01-01T23:59:59.000Z

97

Modeling nitrogen cycling in forested watersheds of Chesapeake Bay  

Science Conference Proceedings (OSTI)

The Chesapeake Bay Agreement calls for a 40% reduction of controllable phosphorus and nitrogen to the tidal Bay by the year 2000. To accomplish this goal the Chesapeake Bay Program needs accurate estimates of nutrient loadings, including atmospheric deposition, from various land uses. The literature was reviewed on forest nitrogen pools and fluxes, and nitrogen data from research catchments in the Chesapeake Basin were identified. The structure of a nitrogen module for forests is recommended for the Chesapeake Bay Watershed Model along with the possible functional forms for fluxes.

Hunsaker, C.T.; Garten, C.T.; Mulholland, P.J.

1995-03-01T23:59:59.000Z

98

The FIT 2.0 Model - Fuel-cycle Integration and Tradeoffs  

Science Conference Proceedings (OSTI)

All mass streams from fuel separation and fabrication are products that must meet some set of product criteria – fuel feedstock impurity limits, waste acceptance criteria (WAC), material storage (if any), or recycle material purity requirements such as zirconium for cladding or lanthanides for industrial use. These must be considered in a systematic and comprehensive way. The FIT model and the “system losses study” team that developed it [Shropshire2009, Piet2010b] are steps by the Fuel Cycle Technology program toward an analysis that accounts for the requirements and capabilities of each fuel cycle component, as well as major material flows within an integrated fuel cycle. This will help the program identify near-term R&D needs and set longer-term goals. This report describes FIT 2, an update of the original FIT model.[Piet2010c] FIT is a method to analyze different fuel cycles; in particular, to determine how changes in one part of a fuel cycle (say, fuel burnup, cooling, or separation efficiencies) chemically affect other parts of the fuel cycle. FIT provides the following: Rough estimate of physics and mass balance feasibility of combinations of technologies. If feasibility is an issue, it provides an estimate of how performance would have to change to achieve feasibility. Estimate of impurities in fuel and impurities in waste as function of separation performance, fuel fabrication, reactor, uranium source, etc.

Steven J. Piet; Nick R. Soelberg; Layne F. Pincock; Eric L. Shaber; Gregory M Teske

2011-06-01T23:59:59.000Z

99

A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling  

E-Print Network (OSTI)

Under typical PEM fuel cell operating conditions, part of membrane electrode assembly is subjected to humidity cycling due to variation of inlet gas RH and/or flow rate. Cyclic membrane hydration/dehydration would cause cyclic swelling/shrinking of the unconstrained membrane. In a constrained membrane, it causes cyclic stress resulting in mechanical failure in the area adjacent to the gas inlet. A mathematical modeling framework for prediction of the lifetime of a PEM FC membrane subjected to hydration cycling is developed in this paper. The model predicts membrane lifetime as a function of RH cycling amplitude and membrane mechanical properties. The modeling framework consists of three model components: a fuel cell RH distribution model, a hydration/dehydration induced stress model that predicts stress distribution in the membrane, and a damage accrual model that predicts membrane life-time. Short descriptions of the model components along with overall framework are presented in the paper. The model was used for lifetime prediction of a GORE-SELECT membrane.

S. F. Burlatsky; M. Gummalla; J. O'Neill; V. V. Atrazhev; A. N. Varyukhin; D. V. Dmitriev; N. S. Erikhman

2013-06-19T23:59:59.000Z

100

GREET 1.5 - transportation fuel-cycle model - Vol. 1 : methodology, development, use, and results.  

DOE Green Energy (OSTI)

This report documents the development and use of the most recent version (Version 1.5) of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel-cycle emissions and energy associated with various transportation fuels and advanced vehicle technologies for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, particulate matter with diameters of 10 micrometers or less, and sulfur oxides) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates total energy consumption, fossil fuel consumption, and petroleum consumption when various transportation fuels are used. The GREET model includes the following cycles: petroleum to conventional gasoline, reformulated gasoline, conventional diesel, reformulated diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied natural gas, liquefied petroleum gas, methanol, Fischer-Tropsch diesel, dimethyl ether, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydropower, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; soybeans to biodiesel; flared gas to methanol, dimethyl ether, and Fischer-Tropsch diesel; and landfill gases to methanol. This report also presents the results of the analysis of fuel-cycle energy use and emissions associated with alternative transportation fuels and advanced vehicle technologies to be applied to passenger cars and light-duty trucks.

Wang, M. Q.

1999-10-06T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Long Cycles in a Perturbed Mean Field Model of a Boson Gas  

E-Print Network (OSTI)

In this paper we give a precise mathematical formulation of the relation between Bose condensation and long cycles and prove its validity for the perturbed mean field model of a Bose gas. We decompose the total density $\\rho=\\rho_{{\\rm short}}+\\rho_{{\\rm long}}$ into the number density of particles belonging to cycles of finite length ($\\rho_{{\\rm short}}$) and to infinitely long cycles ($\\rho_{{\\rm long}}$) in the thermodynamic limit. For this model we prove that when there is Bose condensation, $\\rho_{{\\rm long}}$ is different from zero and identical to the condensate density. This is achieved through an application of the theory of large deviations. We discuss the possible equivalence of $\\rho_{{\\rm long}}\

Teunis C. Dorlas; Philippe A. Martin; Joseph V. Pulé

2005-04-22T23:59:59.000Z

102

Methane Emissions from Natural Wetlands in the United States: Satellite-Derived Estimation Based on Ecosystem Carbon Cycling  

Science Conference Proceedings (OSTI)

Wetlands are an important natural source of methane to the atmosphere. The amounts of methane emitted from inundated ecosystems in the United States can vary greatly from area to area. Seasonal temperature, water table dynamics, and carbon ...

Christopher Potter; Steven Klooster; Seth Hiatt; Matthew Fladeland; Vanessa Genovese; Peggy Gross

2006-12-01T23:59:59.000Z

103

Mathematical model of steam generator feed system at power unit of nuclear plant  

Science Conference Proceedings (OSTI)

A mathematical model of a steam generator feed system at a power unit of a nuclear plant with variable values of transfer function coefficients is presented. The model is realized in the MATLAB/Simulink/Stateflow event-driven simulation.

E. M. Raskin; L. A. Denisova; V. P. Sinitsyn; Yu. V. Nesterov

2011-05-01T23:59:59.000Z

104

Modeling the Effect of Chlorine Emissions on Ozone Levels over the Eastern United States  

Science Conference Proceedings (OSTI)

This paper presents model estimates of the effect of chlorine emissions on atmospheric ozone concentrations in the eastern United States. The model included anthropogenic molecular chlorine emissions, anthropogenic hypochlorous acid emissions ...

Golam Sarwar; Prakash V. Bhave

2007-07-01T23:59:59.000Z

105

The Global Hydrological Cycle and Atmospheric Shortwave Absorption in Climate Models under CO2 Forcing  

Science Conference Proceedings (OSTI)

The spread among the predictions by climate models for the strengthening of the global hydrological cycle [i.e., the global mean surface latent heat flux (LH), or, equivalently, precipitation] at a given level of CO2-induced global warming is of ...

Ken Takahashi

2009-11-01T23:59:59.000Z

106

A Simple Model for the Baroclinic Life Cycle of Meridionally Elongated Eddies in Uniform Shear  

Science Conference Proceedings (OSTI)

A highly simplified model for the wave–mean flow interaction in a baroclinic wave life cycle is derived from the quasigeostrophic two-layer system. The simplification is based on a sheared disturbance embedded in a zonal mean flow with uniform ...

Thomas Frisius

1999-10-01T23:59:59.000Z

107

Performance modelling and simulated availability of shell gasification and carbon recovery unit of urea plant  

Science Conference Proceedings (OSTI)

The present paper deals with the performance modelling and simulated availability of shell gasification and carbon recovery unit of urea plant. The fertilizer plant comprises of various units viz. shell gasification and carbon recovery, desulphurisation, ... Keywords: modelling, performance evaluation and maintenance strategies, steady state availability

Sunand Kumar; Sanjeev Kumar; P. C. Tewari

2007-08-01T23:59:59.000Z

108

Fuel-Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with the GREET Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Cycle Analysis of Hydrogen-Powered Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with the GREET Model Michael Wang Argonne National Laboratory June 10, 2008 Project ID # AN2 This presentation does not contain any proprietary, confidential, or otherwise restricted information 2 Overview * Project start date: Oct. 2002 * Project end date: Continuous * Percent complete: N/A * Inconsistent data, assumptions, and guidelines * Suite of models and tools * Unplanned studies and analyses * Total project funding from DOE: $2.04 million through FY08 * Funding received in FY07: $450k * Funding for FY08: $840k Budget * H2A team * PSAT team * NREL * Industry stakeholders Partners Timeline Barriers to Address 3 Objectives * Expand and update the GREET model for hydrogen production pathways and for applications of FCVs and other FC systems

109

Unit Process Modeling [Nuclear Waste Management using Electrometallurg...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Safety Materials Disposition Decontamination & Decommissioning Nuclear Criticality Safety Nuclear Data Program Nuclear Waste Form Modeling Departments Engineering...

110

Development of a Scale Model for High Flux Isotope Reactor Cycle 400  

Science Conference Proceedings (OSTI)

The development of a comprehensive SCALE computational model for the High Flux Isotope Reactor (HFIR) is documented and discussed in this report. The SCALE model has equivalent features and functionality as the reference MCNP model for Cycle 400 that has been used extensively for HFIR safety analyses and for HFIR experiment design and analyses. Numerical comparisons of the SCALE and MCNP models for the multiplication constant, power density distribution in the fuel, and neutron fluxes at several locations in HFIR indicate excellent agreement between the results predicted with the two models. The SCALE HFIR model is presented in sufficient detail to provide the users of the model with a tool that can be easily customized for various safety analysis or experiment design requirements.

Ilas, Dan [ORNL

2012-03-01T23:59:59.000Z

111

The Sulfur-Iodine Cycle: Process Analysis and Design Using Comprehensive Phase Equilibrium Measurements and Modeling  

DOE Green Energy (OSTI)

Of the 100+ thermochemical hydrogen cycles that have been proposed, the Sulfur-Iodine (S-I) Cycle is a primary target of international interest for the centralized production of hydrogen from nuclear power. However, the cycle involves complex and highly nonideal phase behavior at extreme conditions that is only beginning to be understood and modeled for process simulation. The consequence is that current designs and efficiency projections have large uncertainties, as they are based on incomplete data that must be extrapolated from property models. This situation prevents reliable assessment of the potential viability of the system and, even more, a basis for efficient process design. The goal of this NERI award (05-006) was to generate phase-equilibrium data, property models, and comprehensive process simulations so that an accurate evaluation of the S-I Cycle could be made. Our focus was on Section III of the Cycle, where the hydrogen is produced by decomposition of hydroiodic acid (HI) in the presence of water and iodine (I2) in a reactive distillation (RD) column. The results of this project were to be transferred to the nuclear hydrogen community in the form of reliable flowsheet models for the S-I process. Many of the project objectives were achieved. At Clemson University, a unique, tantalum-based, phase-equilibrium apparatus incorporating a view cell was designed and constructed for measuring fluid-phase equilibria for mixtures of iodine, HI, and water (known as HIx) at temperatures to 350 °C and pressures to 100 bar. Such measurements were of particular interest for developing a working understanding of the expected operation of the RD column in Section III. The view cell allowed for the IR observation and discernment of vapor-liquid (VL), liquid-liquid, and liquid-liquid-vapor (LLVE) equilibria for HIx systems. For the I2-H2O system, liquid-liquid equilibrium (LLE) was discovered to exist at temperatures up to 310-315 °C, in contrast to the models and predictions of earlier workers. For the I2-HI-H2O ternary, LLE and LLVE were all observed for the first time at temperatures of 160 and 200 °C. Three LLE tie-lines were measured at 160 °C, and preliminary indications are that the underlying phase behavior could result in further improvements in the performance of the S-I Cycle. Unfortunately, these new results were obtained too late in the project to be incorporated into the modeling and simulation work described below. At the University of Virginia, a uniquely complete and reliable model was developed for the thermodynamic properties of HIx, covering the range of conditions expected for the separation of product hydrogen and recycled iodine in the RD column located in Section III. The model was validated with all available property spectroscopy data. The results provide major advances over prior understanding of the chemical speciation involved. The model was implemented in process simulation studies of the S-I Cycle, which showed improvement in energy efficiency to 42%, as well as significantly smaller capital requirements due to lower pressure operation and much smaller equipment sizes. The result is that the S-I Cycle may be much more economically feasible than was previously thought. If both the experimental and modeling work described above were to be continued to ultimate process optimization, both the American public and the global community would benefit from this alternative energy source that does not produce carbon emissions.

Thies, Mark C.; O'Connell, J. P.; Gorensek, Maximilian B.

2010-01-10T23:59:59.000Z

112

An expandable software model for collaborative decision making during the whole building life cycle  

SciTech Connect

Decisions throughout the life cycle of a building, from design through construction and commissioning to operation and demolition, require the involvement of multiple interested parties (e.g., architects, engineers, owners, occupants and facility managers). The performance of alternative designs and courses of action must be assessed with respect to multiple performance criteria, such as comfort, aesthetics, energy, cost and environmental impact. Several stand-alone computer tools are currently available that address specific performance issues during various stages of a building's life cycle. Some of these tools support collaboration by providing means for synchronous and asynchronous communications, performance simulations, and monitoring of a variety of performance parameters involved in decisions about a building during building operation. However, these tools are not linked in any way, so significant work is required to maintain and distribute information to all parties. In this paper we describe a software model that provides the data management and process control required for collaborative decision making throughout a building's life cycle. The requirements for the model are delineated addressing data and process needs for decision making at different stages of a building's life cycle. The software model meets these requirements and allows addition of any number of processes and support databases over time. What makes the model infinitely expandable is that it is a very generic conceptualization (or abstraction) of processes as relations among data. The software model supports multiple concurrent users, and facilitates discussion and debate leading to decision making. The software allows users to define rules and functions for automating tasks and alerting all participants to issues that need attention. It supports management of simulated as well as real data and continuously generates information useful for improving performance prediction and understanding of the effects of proposed technologies and strategies.

Papamichael, K.; Pal, V.; Bourassa, N.; Loffeld, J.; Capeluto, G.

2000-04-01T23:59:59.000Z

113

Geology And A Working Conceptual Model Of The Obsidian Butte (Unit 6)  

Open Energy Info (EERE)

Geology And A Working Conceptual Model Of The Obsidian Butte (Unit 6) Geology And A Working Conceptual Model Of The Obsidian Butte (Unit 6) Sector Of The Salton Sea Geothermal Field, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Geology And A Working Conceptual Model Of The Obsidian Butte (Unit 6) Sector Of The Salton Sea Geothermal Field, California Details Activities (2) Areas (1) Regions (0) Abstract: A working conceptual model has been developed for the southwestern portion of the Salton Sea geothermal system, the region encompasing CalEnergy Operating Company's imnent 'Unit 6' field expansion (185 megawatts). The model is based on examination and analysis of several thousand borehole rock samples combined with a wealth of subsurface information made available for the first time from the databases of present

114

MODELING THE DEMAND FOR E85 IN THE UNITED STATES  

SciTech Connect

How demand for E85 might evolve in the future in response to changing economics and policies is an important subject to include in the National Energy Modeling System (NEMS). This report summarizes a study to develop an E85 choice model for NEMS. Using the most recent data from the states of Minnesota, North Dakota, and Iowa, this study estimates a logit model that represents E85 choice as a function of prices of E10 and E85, as well as fuel availability of E85 relative to gasoline. Using more recent data than previous studies allows a better estimation of non-fleet demand and indicates that the price elasticity of E85 choice appears to be higher than previously estimated. Based on the results of the econometric analysis, a model for projecting E85 demand at the regional level is specified. In testing, the model produced plausible predictions of US E85 demand to 2040.

Liu, Changzheng [ORNL] [ORNL; Greene, David L [ORNL] [ORNL

2013-10-01T23:59:59.000Z

115

Objective selection of suitable unit cell size in data-driven modeling of mineral prospectivity  

Science Conference Proceedings (OSTI)

In GIS-based data-driven modeling of mineral prospectivity, a suitably fine unit cell size is used for spatial representation of known occurrences of mineral deposits of the type sought (D) in a study area (T). However, until now, the unit cell size ... Keywords: Fractal analysis, GIS, Point pattern analysis, Spatial contrast, Weights-of-evidence

Emmanuel John M. Carranza

2009-10-01T23:59:59.000Z

116

Climatology Models for Extreme Hurricane Winds near the United States  

Science Conference Proceedings (OSTI)

The rarity of severe coastal hurricanes implies that empirical estimates of extreme wind speed return levels will be unreliable. Here climatology models derived from extreme value theory are estimated using data from the best-track [Hurricane ...

Thomas H. Jagger; James B. Elsner

2006-07-01T23:59:59.000Z

117

Modeling of Electronically Commutated Motor Controlled Fan-powered Terminal Units  

E-Print Network (OSTI)

Empirical models of airflow and power consumption were developed for series and parallel variable air volume fan powered terminal units (FPTUs). An experimental setup and test procedure were developed to test the terminal units over typical operating ranges. The terminal units in this study used either an 8 in. (20.32 cm) or a 12 in. (30.48 cm) primary air inlet. All terminal units utilized electronically commutated motor (ECM) controllers. Data collected were compared against previous data collected for silicon controlled rectifier (SCR) units. Generalized models were developed for both series and parallel units, and compared against models developed for SCR units. In addition to the performance modeling, power factor and power quality data were also collected for each terminal unit. The power quality analysis included recording and analyzing harmonic distortion for current, voltage, and power up to the 25th harmonic. The total harmonic distortion (THD) was also recorded and presented. For the series terminal units, models were developed for fan airflow, fan power, and primary airflow. The models for fan airflow all had R2 values above 0.987. The models for fan power all had R2 values above 0.968. The models for primary airflow all had R2 values above 0.895. For the parallel terminal units, models were developed for leakage, fan airflow, fan power, and primary airflow. All of the leakage models had R2 values above 0.826. All of the fan airflow models had R2 values above 0.955. All of the fan power models had R2 values above 0.922. All of the primary airflow models had R2 values above 0.872. The real power THD was below 1.5 percent for both series and parallel FPTUs. The current THD ranged from 84 percent to 172 percent for series FPTUs and from 83 percent to 183 percent for parallel FPTUs. The voltage THD was below 1.4 percent for both series and parallel FPTUs. The performance models developed will help improve the accuracy of building energy simulation programs for heating, ventilation, and air conditioning (HVAC) systems utilizing ECM controlled FPTUs. Increasing the accuracy of these simulations will allow HVAC system designers to better optimize their designs for specific building types in a wide variety of climates.

Edmondson, Jacob Lee

2009-12-01T23:59:59.000Z

118

Regional Climate Change Scenarios over the United States Produced with a Nested Regional Climate Model  

Science Conference Proceedings (OSTI)

In this paper two continuous 3½-year-long climate simulations over the continental United States are discussed, one for present-day conditions and one for conditions under double carbon dioxide concentration, conducted with a limited area model (...

Filippo Giorgi; Christine Shields Brodeur; Gary T. Bates

1994-03-01T23:59:59.000Z

119

Performance of the United Kingdom Meteorological Office Global Model in Predicting the Movement of Tropical Cyclones  

Science Conference Proceedings (OSTI)

A detailed evaluation of the performance of the United Kingdom Meteorological Office Global Model (UKMO) in predicting the movement of 15 tropical cyclones (TCs) that occurred over the western North Pacific during 1987 is presented. The ...

Johnny C. L. Chan; Wai-Kau Kay

1993-09-01T23:59:59.000Z

120

Detailed Spatial Modeling of Carbon Capture and Storage Infrastructure Deployment in the Southwestern United States  

E-Print Network (OSTI)

, Pipeline and Hazardous Materials Administration. 13. US EPA, eGRID Database. 2006, United States are given by EPA Egrid data USEPA (2006) and costs are calculated using the IECM model (Berkenpas et al

California at Davis, University of

Note: This page contains sample records for the topic "modeling cycling units" 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

A Conterminous United States Multilayer Soil Characteristics Dataset for Regional Climate and Hydrology Modeling  

Science Conference Proceedings (OSTI)

Soil information is now widely required by many climate and hydrology models and soil–vegetation–atmosphere transfer schemes. This paper describes the development of a multilayer soil characteristics dataset for the conterminous United States (...

Douglas A. Miller; Richard A. White

1998-01-01T23:59:59.000Z

122

Modeling land surface processes of the midwestern United States : predicting soil moisture under a warmer climate  

E-Print Network (OSTI)

This dissertation seeks to quantify the response of soil moisture to climate change in the midwestern United States. To assess this response, a dynamic global vegetation model, Integrated Biosphere Simulator, was coupled ...

Winter, Jonathan (Jonathan Mark)

2010-01-01T23:59:59.000Z

123

Terrestrial Carbon Sinks for the United States Predicted from MODIS Satellite Data and Ecosystem Modeling  

Science Conference Proceedings (OSTI)

A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of the conterminous United States ...

Christopher Potter; Steven Klooster; Alfredo Huete; Vanessa Genovese

2007-08-01T23:59:59.000Z

124

The Rail Technology Unit Modelling the Behaviour of Freight Vehicles  

E-Print Network (OSTI)

., in- ference 0.8 sec. (4) overhead of loading models, image re- sizing, etc.: 1.4 sec. After human' evaluation is carried out on a test set of video frames from `Buffy: the vampire slayer' (season 5 episode 2 is evaluated on video frames from the `Buffy: the vampire slayer' TV show and images from the PASCAL VOC 2008

125

Modelling of environmental impacts of solid waste landfilling within the life-cycle analysis program EASEWASTE  

Science Conference Proceedings (OSTI)

A new computer-based life-cycle assessment model (EASEWASTE) has been developed to evaluate resource and environmental consequences of solid waste management systems. This paper describes the landfilling sub-model used in the life-cycle assessment program EASEWASTE, and examines some of the implications of this sub-model. All quantities and concentrations of leachate and landfill gas can be modified by the user in order to bring them in agreement with the actual landfill that is assessed by the model. All emissions, except the generation of landfill gas, are process specific. The landfill gas generation is calculated on the basis of organic matter in the landfilled waste. A landfill assessment example is provided. For this example, the normalised environmental effects of landfill gas on global warming and photochemical smog are much greater than the environmental effects for landfill leachate or for landfill construction. A sensitivity analysis for this example indicates that the overall environmental impact is sensitive to the gas collection efficiency and the use of the gas, but not to the amount of leachate generated, or the amount of soil or liner material used in construction. The landfill model can be used for evaluating different technologies with different liners, gas and leachate collection efficiencies, and to compare the environmental consequences of landfilling with alternative waste treatment options such as incineration or anaerobic digestion.

Kirkeby, Janus T.; Birgisdottir, Harpa [Environment and Resources, Technical University of Denmark, DTU, Building 113, DK-2800 Kgs. Lyngby (Denmark); Bhander, Gurbakash Singh; Hauschild, Michael [Department of Manufacturing Engineering and Management, Technical University of Denmark, Building 424, DK-2800 Lyngby (Denmark); Christensen, Thomas H. [Environment and Resources, Technical University of Denmark, DTU, Building 113, DK-2800 Kgs. Lyngby (Denmark)], E-mail: thc@er.dtu.dk

2007-07-01T23:59:59.000Z

126

Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model  

SciTech Connect

This study explores the impact of wastes generated from potential future fuel cycles and the issues presented by classifying these under current classification criteria, and discusses the possibility of a comprehensive and consistent characteristics-based classification framework based on new waste streams created from advanced fuel cycles. A static mass flow model, Fuel-Cycle Integration and Tradeoffs (FIT), was used to calculate the composition of waste streams resulting from different nuclear fuel cycle choices. This analysis focuses on the impact of waste form heat load on waste classification practices, although classifying by metrics of radiotoxicity, mass, and volume is also possible. The value of separation of heat-generating fission products and actinides in different fuel cycles is discussed. It was shown that the benefits of reducing the short-term fission-product heat load of waste destined for geologic disposal are neglected under the current source-based radioactive waste classification system , and that it is useful to classify waste streams based on how favorable the impact of interim storage is in increasing repository capacity.

Denia Djokic; Steven J. Piet; Layne F. Pincock; Nick R. Soelberg

2013-02-01T23:59:59.000Z

127

Moisture Flux Convergence in Regional and Global Climate Models: Implications for Droughts in the Southwestern United States Under Climate Change  

SciTech Connect

The water cycle of the southwestern United States (SW) is dominated by winter storms that maintain a positive annual net precipitation. Analysis of the control and future climate from four pairs of regional and global climate models (RCMs and GCMs) shows that the RCMs simulate a higher fraction of transient eddy moisture fluxes because the hydrodynamic instabilities associated with flow over complex terrain are better resolved. Under global warming, this enables the RCMs to capture the response of transient eddies to increased atmospheric stability that allows more moisture to converge on the windward side of the mountains by blocking. As a result, RCMs simulate enhanced transient eddy moisture convergence in the SW compared to GCMs, although both robustly simulate drying due to enhanced moisture divergence by the divergent mean flow in a warmer climate. This enhanced convergence leads to reduced susceptibility to hydrological change in the RCMs compared to GCMs.

Gao, Yanhong; Leung, Lai-Yung R.; Salathe, E.; Dominguez, Francina; Nijssen, Bart; Lettenmaier, D. P.

2012-05-10T23:59:59.000Z

128

Power system simulation and optimization models for planning nuclear refueling cycles  

SciTech Connect

From Operation Research Society of America; San Diego, California, USA (12 Nov 1973). The mid-range system being modeled may include a mix of fossil, nuclear, hydro, pumped-storage, and peaking units. For any predetermined nuclear refueling schedule, the program (ORSIM) determines an approximately optical plan of operation for the system. This includes the determination of a maintenance schedule for the non-nuclear units and a schedule of energy delivery for each plant in the system. The criterion of optimality is the minimization of the total discounted operating cost of the system over the specified study period. Over this period, the model computes the expected station load factors, the loss of load probability and unserved energy for the system, and the production costs of operating so as to meet the forecasted loads on the system. The code takes account of variations and growth in demand over the planning horizon, occurrence of unit forced outages, planned shutdowns for nuclear refuelings, maintenance scheduling, allocations of fixed hydro and nuclear energies, and interactions between nuclear unit reloadings and fuel costs. 13 references. (auth)

Turnage, J.C.; Bennett, L.L.; Joy, D.S.; Prince, B.E.

1973-10-01T23:59:59.000Z

129

User manual for GEOCOST: a computer model for geothermal cost analysis. Volume 2. Binary cycle version  

DOE Green Energy (OSTI)

A computer model called GEOCOST has been developed to simulate the production of electricity from geothermal resources and calculate the potential costs of geothermal power. GEOCOST combines resource characteristics, power recovery technology, tax rates, and financial factors into one systematic model and provides the flexibility to individually or collectively evaluate their impacts on the cost of geothermal power. Both the geothermal reservoir and power plant are simulated to model the complete energy production system. In the version of GEOCOST in this report, geothermal fluid is supplied from wells distributed throughout a hydrothermal reservoir through insulated pipelines to a binary power plant. The power plant is simulated using a binary fluid cycle in which the geothermal fluid is passed through a series of heat exchangers. The thermodynamic state points in basic subcritical and supercritical Rankine cycles are calculated for a variety of working fluids. Working fluids which are now in the model include isobutane, n-butane, R-11, R-12, R-22, R-113, R-114, and ammonia. Thermodynamic properties of the working fluids at the state points are calculated using empirical equations of state. The Starling equation of state is used for hydrocarbons and the Martin-Hou equation of state is used for fluorocarbons and ammonia. Physical properties of working fluids at the state points are calculated.

Huber, H.D.; Walter, R.A.; Bloomster, C.H.

1976-03-01T23:59:59.000Z

130

Modeling of ECM Controlled Series Fan-powered VAV Terminal Units  

E-Print Network (OSTI)

Semi-empirical models for series fan-powered variable air volume terminal units (FPTUs) were developed based on models of the primary, plenum, fan airflow and the fan power consumption. The experimental setups and test procedures were developed respectively for primary, plenum and fan airflow to test each component of the FPTUs at typical design pressures and airflows. Two sizes of the terminal units from three manufacturers were used in this study. All of the FPTUs were equipped with electronically commutated motors (ECM). Data provided by the models were compared against the data from previous experiments to prove the models’ validity. Regression modeling was performed by using SigmaStat. The model of primary airflow had an R2 above 0.948 for all the terminal units evaluated while the plenum airflow model had an R2 above 0.99. For all the terminal units, the R2 of the fan airflow model was ranged from 0.973 to 0.998. Except for one fan, the fan power consumption model was able to characterize the power performance and had an R2 above 0.986. By combining the airflow and power models, the model for series FPTU was developed. Verification was made to prove the FPTU model’s validity by comparing the measured and predicted data of airflow and power consumption. Correction factors were used in the primary airflow model to compensate for the difference caused by large measurement errors and the system effects. The predicted values were consistent with measurements and no offset was needed in the primary airflow model. Generally, the newly established model was able to describe the airflow performance as well as power consumption of series FPTUs without adding complexity.

Yin, Peng

2010-08-01T23:59:59.000Z

131

Evaluating Surface Water Cycle Simulated by the Australian Community Land Surface Model (CABLE) across Different Spatial and Temporal Domains  

Science Conference Proceedings (OSTI)

The terrestrial water cycle in the Australian Community Atmosphere Biosphere Land Exchange (CABLE) model has been evaluated across a range of temporal and spatial domains. A series of offline experiments were conducted using the forcing data from ...

Huqiang Zhang; Bernard Pak; Ying Ping Wang; Xinyao Zhou; Yongqiang Zhang; Liang Zhang

2013-08-01T23:59:59.000Z

132

A Comparison of Climates Simulated by a General Circulation Model when Run in the Annual Cycle and Perpetual Modes  

Science Conference Proceedings (OSTI)

A comparison is made between the climate simulated by the Canadian Climate Centre (CCC) General Circulation Model when run its usual “annual cycle”mode, in which the solar declination angle varies annually, and the climate which is simulated when ...

F. W. Zwiers; G. J. Boer

1987-11-01T23:59:59.000Z

133

Hydrological cycles over the Congo and Upper Blue Nile basins: Evaluation of General Circulation Models Simulations and Reanalysis Data Products  

Science Conference Proceedings (OSTI)

The simulations and predictions of the hydrological cycle by General Circulation Models (GCMs) are characterized by a significant degree of uncertainty. This uncertainty is reflected in the range of IPCC (Intergovernmental Panel on Climate Change) ...

Mohamed S. Siam; Marie-Estelle Demory; Elfatih A. B. Eltahir

134

Simulation of the Global Hydrological Cycle in the CCSM Community Atmosphere Model Version 3 (CAM3): Mean Features  

Science Conference Proceedings (OSTI)

The seasonal and annual climatological behavior of selected components of the hydrological cycle are presented from coupled and uncoupled configurations of the atmospheric component of the Community Climate System Model (CCSM) Community ...

James J. Hack; Julie M. Caron; Stephen G. Yeager; Keith W. Oleson; Marika M. Holland; John E. Truesdale; Philip J. Rasch

2006-06-01T23:59:59.000Z

135

Life Cycle Environmental Impacts Resulting from the Manufacture of the Heliostat Field for a Reference Power Tower Design in the United States: Preprint  

SciTech Connect

Life cycle assessment (LCA) is recognized as a useful analytical approach for quantifying environmental impacts of renewable energy technologies, including concentrating solar power (CSP). An LCA accounts for impacts from all stages in the development, operation, and decommissioning of a CSP plant, including such upstream stages as the extraction of raw materials used in system components, manufacturing of those components, and construction of the plant. The National Renewable Energy Laboratory is conducting a series of LCA studies for various CSP technologies. This paper contributes to a thorough LCA of a 100 MWnet molten salt power tower CSP plant by estimating the environmental impacts resulting from the manufacture of heliostats. Three life cycle metrics are evaluated: greenhouse gas emissions, water consumption, and cumulative energy demand. The heliostat under consideration (the 148 m2 Advanced Thermal Systems heliostat) emits 5,300 kg CO2eq, consumes 274 m3 of water, and requires 159,000 MJeq during its manufacture. Future work will incorporate the results from this study into the LCA model used to estimate the life cycle impacts of the entire 100 MWnet power tower CSP plant.

Heath, G.; Burkhardt, J.; Turchi, C.

2012-10-01T23:59:59.000Z

136

On-line Fault Diagnosis Model of the Hydropower Units Based on MAS  

Science Conference Proceedings (OSTI)

The paper introduced a novel on-line fault diagnosis system model of the hydropower units based on multi-agent system. In allusion to the classical MAS-based fault diagnosis model, it proposes a new function of information interactive between the mission-controlled ...

Liao Jiaping; Fu Bo; Chen Yu

2009-07-01T23:59:59.000Z

137

Nonlinear Dynamical Model of Regime Switching Between Conventions and Business Cycles  

E-Print Network (OSTI)

We introduce and study a non-equilibrium continuous-time dynamical model of the price of a single asset traded by a population of heterogeneous interacting agents in the presence of uncertainty and regulatory constraints. The model takes into account (i) the price formation delay between decision and investment by the second-order nature of the dynamical equations, (ii) the linear and nonlinear mean-reversal or their contrarian in the form of speculative price trading, (iii) market friction, (iv) uncertainty in the fundamental value which controls the amplitude of mispricing, (v) nonlinear speculative momentum effects and (vi) market regulations that may limit large mispricing drifts. We find markets with coexisting equilibrium, conventions and business cycles, which depend on (a) the relative strength of value-investing versus momentum-investing, (b) the level of uncertainty on the fundamental value and (c) the degree of market regulation. The stochastic dynamics is characterized by nonlinear geometric rando...

Yukalov, V I; Yukalova, E P

2008-01-01T23:59:59.000Z

138

Regional climate change scenarios over the United States produced with a nested regional climate model  

Science Conference Proceedings (OSTI)

Two continuous 31/2-year-long climate simulation over the continental United States are discussed, one of present-day conditions and one for conditions under double carbon dioxide concentration, conducted with a limited area model (LAM) nested in a general circulation model (GCM). The models used are a version of the NCAR Community Climate Model (CCM) at rhomboidal 15 spectral resolution and the climate version of the NCAR/Penn State mesoscale model (MM4) at 60-km gridpoint spacing. For present-day conditions the model temperatures are within 1[degrees]-2[degrees]C of observations except over the Great Lakes region, where temperature is overpredicted. The CCM overpredicts precipitation throughout the continental United States (overall by about 60%) and especially over the West (by up to 300%). The nested MM4 overpredicts precipitation over the West but underpredicts it over the eastern United States. In addition, it produces a large amount of topographically and lake-induced sub-GCM grid-scale detail that compares well with available high-resolution climate data. Overall, the nested MM4 reproduces observed spatial and seasonal precipitation patterns better than the driving CCM. Doubled carbon dioxide-induced temperature change scenarios produced by the two models generally differ by less than several tenths of a degree except over the Great Lakes region where, because of the presence of the lakes in the nested model, the two model scenarios differ by more than one degree. Conversely, precipitation change scenarios from the two model simulations can locally differ in magnitude, sign, spatial, and seasonal detail. These differences are associated with topographical features in the MM4, such as the presence of steep coastal ranges in the western United States. This work illustrates the feasibility of the use of the nested modeling technique for long-term regional climate simulation. 43 refs., 19 figs., 6 tabs.

Giorgi, F.; Brodeur, C.S.; Bates, G.T. (National Center for Atmospheric Research, Boulder, CO (United States))

1994-03-01T23:59:59.000Z

139

Home composting as an alternative treatment option for organic household waste in Denmark: An environmental assessment using life cycle assessment-modelling  

SciTech Connect

An environmental assessment of the management of organic household waste (OHW) was performed from a life cycle perspective by means of the waste-life cycle assessment (LCA) model EASEWASTE. The focus was on home composting of OHW in Denmark and six different home composting units (with different input and different mixing frequencies) were modelled. In addition, incineration and landfilling was modelled as alternatives to home composting. The most important processes contributing to the environmental impact of home composting were identified as greenhouse gas (GHG) emissions (load) and the avoided emissions in relation to the substitution of fertiliser and peat when compost was used in hobby gardening (saving). The replacement of fertiliser and peat was also identified as one of the most sensible parameters, which could potentially have a significant environmental benefit. Many of the impact categories (especially human toxicity via water (HTw) and soil (HTs)) were affected by the heavy metal contents of the incoming OHW. The concentrations of heavy metals in the compost were below the threshold values for compost used on land and were thus not considered to constitute a problem. The GHG emissions were, on the other hand, dependent on the management of the composting units. The frequently mixed composting units had the highest GHG emissions. The environmental profiles of the home composting scenarios were in the order of -2 to 16 milli person equivalents (mPE) Mg{sup -1} wet waste (ww) for the non-toxic categories and -0.9 to 28 mPE Mg{sup -1} ww for the toxic categories. Home composting performed better than or as good as incineration and landfilling in several of the potential impact categories. One exception was the global warming (GW) category, in which incineration performed better due to the substitution of heat and electricity based on fossil fuels.

Andersen, J.K.; Boldrin, A.; Christensen, T.H. [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Scheutz, C., E-mail: chas@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark)

2012-01-15T23:59:59.000Z

140

Model of the Feed Water System Including a Generic Model of the Deaerator for a Full Scope Combined Cycle Power Plant Simulator  

Science Conference Proceedings (OSTI)

This paper presents the modelling of the Feed water System and an original generic model for closed vessels containing a fluid in two phases at equilibrium conditions with an incondensable gas. The model was used for the deaerator of a Combined Cycle ... Keywords: deaerator, pressurised vessels model, feedwater simulation

Edgardo J. Roldan-Villasana; Ana K. Vazquez

2010-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Primitive-Equation-Based Low-Order Models with Seasonal Cycle. Part I: Model Construction  

Science Conference Proceedings (OSTI)

In a continuation of previous investigations on deterministic reduced atmosphere models with compact state space representation, two main modifications are introduced. First, primitive equation dynamics is used to describe the nonlinear ...

Ulrich Achatz; J. D. Opsteegh

2003-02-01T23:59:59.000Z

142

Water-Use Efficiency of the Terrestrial Biosphere: A Model Analysis Focusing on Interactions between the Global Carbon and Water Cycles  

Science Conference Proceedings (OSTI)

Carbon and water cycles are intimately coupled in terrestrial ecosystems, and water-use efficiency (WUE; carbon gain at the expense of unit water loss) is one of the key parameters of ecohydrology and ecosystem management. In this study, the ...

Akihiko Ito; Motoko Inatomi

2012-04-01T23:59:59.000Z

143

Update 5 to: A Dispersion Modeling Analysis of Downwash from...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant: Modeling Cycling Units 1, 2 plus One Baseload Unit Update 5 to: A Dispersion Modeling...

144

On the relationship between uncertainties in tropical divergence and the hydrological cycle in global models  

Science Conference Proceedings (OSTI)

A survey of tropical divergence from three GCMs, three global reanalyses and four insitu soundings from field campaigns shows the existence of large uncertainties in the ubiquity of shallow divergent circulation as well as the depth and strength of the deep divergent circulation. More specifically, only two GCMs out of the three GCMs and three global reanalyses show significant shallow divergent circulation, which is present in all in-situ soundings, and of the three GCMs and three global reanalyses, only two global reanalyses have deep divergence profiles that lie within the range of uncertainty of the soundings. The relationships of uncertainties in the shallow and deep divergent circulation to uncertainties in present day and projected strength of the hydrological cycle from the GCMs are assessed. In the tropics and subtropics, deep divergent circulation is the largest contributor to moisture convergence that balances the net precipitation, and inter-model differences in the present day simulations carry over onto the future projections. In comparison to the soundings and reanalyses, the GCMs are found to have deeper and stronger divergent circulation. While these two characteristics of GCM divergence affect the strength of the hydrological cycle, they tend to compensate for each other so that their combined effect is relatively modest.

Hagos, Samson M.; Leung, Lai-Yung R.

2012-01-01T23:59:59.000Z

145

Evaluation of the Daylight Cycle of Model-Predicted Cloud Amount and Condensed Water Path over Europe with Observations from MSG SEVIRI  

Science Conference Proceedings (OSTI)

The evaluation of the diurnal cycle of cloud amount (CA) and cloud condensed water path (CWP) as predicted by climate models receives relatively little attention, mostly because of the lack of observational data capturing the diurnal cycle of ...

R. A. Roebeling; E. van Meijgaard

2009-04-01T23:59:59.000Z

146

Regional Climate Model Simulation of U.S. Precipitation during 1982–2002. Part I: Annual Cycle  

Science Conference Proceedings (OSTI)

The fifth-generation PSU–NCAR Mesoscale Model (MM5)-based regional climate model (CMM5) capability in simulating the U.S. precipitation annual cycle is evaluated with a 1982–2002 continuous baseline integration driven by the NCEP–DOE second ...

Xin-Zhong Liang; Li Li; Kenneth E. Kunkel; Mingfang Ting; Julian X. L. Wang

2004-09-01T23:59:59.000Z

147

EVALUATING THE LAND AND OCEAN COMPONENTS OF THE GLOBAL CARBON CYCLE IN THE CMIP5 EARTH SYSTEM MODELS  

Science Conference Proceedings (OSTI)

We assess the ability of 18 Earth System Models to simulate the land and ocean carbon cycle for the present climate. These models will be used in the next Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) for climate ...

A. Anav; P. Friedlingstein; M. Kidston; L. Bopp; P. Ciais; P. Cox; C. Jones; M. Jung; R. Myneni; Z. Zhu

148

Evaluating the Land and Ocean Components of the Global Carbon Cycle in the CMIP5 Earth System Models  

Science Conference Proceedings (OSTI)

The authors assess the ability of 18 Earth system models to simulate the land and ocean carbon cycle for the present climate. These models will be used in the next Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) for ...

A. Anav; P. Friedlingstein; M. Kidston; L. Bopp; P. Ciais; P. Cox; C. Jones; M. Jung; R. Myneni; Z. Zhu

2013-09-01T23:59:59.000Z

149

Model predictive control system and method for integrated gasification combined cycle power generation  

DOE Patents (OSTI)

Control system and method for controlling an integrated gasification combined cycle (IGCC) plant are provided. The system may include a controller coupled to a dynamic model of the plant to process a prediction of plant performance and determine a control strategy for the IGCC plant over a time horizon subject to plant constraints. The control strategy may include control functionality to meet a tracking objective and control functionality to meet an optimization objective. The control strategy may be configured to prioritize the tracking objective over the optimization objective based on a coordinate transformation, such as an orthogonal or quasi-orthogonal projection. A plurality of plant control knobs may be set in accordance with the control strategy to generate a sequence of coordinated multivariable control inputs to meet the tracking objective and the optimization objective subject to the prioritization resulting from the coordinate transformation.

Kumar, Aditya; Shi, Ruijie; Kumar, Rajeeva; Dokucu, Mustafa

2013-04-09T23:59:59.000Z

150

Environmental Aspects of Advanced Nuclear Fuel Cycles: Parametric Modeling and Preliminary Analysis  

E-Print Network (OSTI)

Nuclear power has the potential to help reduce rising carbon emissions, but to be considered sustainable, it must also demonstrate the availability of an indefinite fuel supply as well as not produce any significant negative environmental effects. The objective of this research was to evaluate the sustainability of nuclear power and to explore the nuclear fuel cycles that best meet this goal. First, the study quantified current and promising nuclear fuel cycles to be further evaluated and developed a set of objective metrics to describe the environmental effects of each cycle. The metrics included such factors as the amount of waste generated and the isotopic composition of the waste. Next, the evaluation used the International Atomic Energy Agency's Nuclear Fuel Cycle Simulation System to compute nuclide compositions at various stages of the fuel cycles. Finally, the study looked at the radioactivity of the waste generated and used this and other characteristics to determine which fuel cycle meets the objectives of sustainability. Results confirm that incorporating recycling into the fuel cycle would help reduce the volume of waste needing to be stored long-term. Also, calculations made with data from the Nuclear Fuel Cycle Simulation System predicted that the waste from fuel cycles using recycling would be slightly more radiotoxic than the open fuel cycle?s waste. However, the small increase in radiotoxicity is a manageable issue and would not detract from the benefits of recycling. Therefore, recycling and reprocessing spent fuel must be incorporated into the nuclear fuel cycle to achieve sustainability.

Yancey, Kristina D.

2010-05-01T23:59:59.000Z

151

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

DOE Green Energy (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

152

Market disruption, cascading effects, and economic recovery:a life-cycle hypothesis model.  

Science Conference Proceedings (OSTI)

This paper builds upon previous work [Sprigg and Ehlen, 2004] by introducing a bond market into a model of production and employment. The previous paper described an economy in which households choose whether to enter the labor and product markets based on wages and prices. Firms experiment with prices and employment levels to maximize their profits. We developed agent-based simulations using Aspen, a powerful economic modeling tool developed at Sandia, to demonstrate that multiple-firm economies converge toward the competitive equilibria typified by lower prices and higher output and employment, but also suffer from market noise stemming from consumer churn. In this paper we introduce a bond market as a mechanism for household savings. We simulate an economy of continuous overlapping generations in which each household grows older in the course of the simulation and continually revises its target level of savings according to a life-cycle hypothesis. Households can seek employment, earn income, purchase goods, and contribute to savings until they reach the mandatory retirement age; upon retirement households must draw from savings in order to purchase goods. This paper demonstrates the simultaneous convergence of product, labor, and savings markets to their calculated equilibria, and simulates how a disruption to a productive sector will create cascading effects in all markets. Subsequent work will use similar models to simulate how disruptions, such as terrorist attacks, would interplay with consumer confidence to affect financial markets and the broader economy.

Sprigg, James A.

2004-11-01T23:59:59.000Z

153

Depositional sequences and integrated recovery efficiency forecast models for San Andres and Clearfork Units in the Central Basin Platform and the Northern Shelf, west Texas  

E-Print Network (OSTI)

This paper develops depositional sequences of the carbonate ramp and the carbonate shelf models for an idealized cycle and multiple cycles of depositions. Based on the developed depositional sequences, the integrated recovery efficiency forecast models of primary, initial waterflood and infill drilling are developed for the San Andres and Clearfork reservoirs in Central Basin Platform and the Northern Shelf, west Texas. The geological parameters and well spacing are considered major factors for controlling recovery efficiencies. The depositional environment and diagenesis are controlling geological factors affecting oil recovery efficiencies. The depositional sequences characterize the vertical and lateral variations of depositional-energy environments in development of the carbonate ramp and the carbonate shelf The depositional-energy environment controls the depositional rock's facies. The well-sorted and large-size grainstones are related to the higher depositional-energy environment. The poorly-sorted and small-size rocks are related to the lower depositional-energy environment. The depositions of the San Andres and Clearfork formation in the Central Basin Platform, separately, follow the prograding-ramp sequences of one major cycle with multiple subcycles. The lumping depositional energy increases from the inner platform to the platform boundary. Similarly, the depositions of San Andres and Clearfork formation in the Northern Shelf also follow one major prograding cycle with multiple subcycles, separately. However, the lumping depositional energy, decreases from the inner platform to the platform boundary. A normalized depositional energy index is defined based on the depositional sequences of the ramp and shelf models. Normalization is also used to define a porosity index and a well spacing index. Linear and exponential regressions on a database are conducted to develop recovery efficiency forecast models which include depositional energy, porosity and well spacing indices. Section 17, Dollarhide Clearfork Unit is used as an example to show the applications of the recovery efficiency forecast models.

Shao, Hongbin

1994-01-01T23:59:59.000Z

154

A Hydrostrat Model and Alternatives for Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainer Mesa-Shoshone Mountain, Nye County, Nevada  

Science Conference Proceedings (OSTI)

The three-dimensional hydrostratigraphic framework model for the Rainier Mesa-Shoshone Mountain Corrective Action Unit was completed in Fiscal Year 2006. The model extends from eastern Pahute Mesa in the north to Mid Valley in the south and centers on the former nuclear testing areas at Rainier Mesa, Aqueduct Mesa, and Shoshone Mountain. The model area also includes an overlap with the existing Underground Test Area Corrective Action Unit models for Yucca Flat and Pahute Mesa. The model area is geologically diverse and includes un-extended yet highly deformed Paleozoic terrain and high volcanic mesas between the Yucca Flat extensional basin on the east and caldera complexes of the Southwestern Nevada Volcanic Field on the west. The area also includes a hydrologic divide between two groundwater sub-basins of the Death Valley regional flow system. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the model area. Three deep characterization wells, a magnetotelluric survey, and reprocessed gravity data were acquired specifically for this modeling initiative. These data and associated interpretive products were integrated using EarthVision{reg_sign} software to develop the three-dimensional hydrostratigraphic framework model. Crucial steps in the model building process included establishing a fault model, developing a hydrostratigraphic scheme, compiling a drill-hole database, and constructing detailed geologic and hydrostratigraphic cross sections and subsurface maps. The more than 100 stratigraphic units in the model area were grouped into 43 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the volcanic units in the model area into 35 hydrostratigraphic units that include 16 aquifers, 12 confining units, 2 composite units (a mixture of aquifer and confining units), and 5 intrusive confining units. The underlying pre-Tertiary rocks are divided into six hydrostratigraphic units, including three aquifers and three confining units. Other units include an alluvial aquifer and a Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units ('layers' in the model). The model also incorporates 56 Tertiary normal faults and 4 Mesozoic thrust faults. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Four of these alternatives were developed so they can be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area Subproject of the Environmental Restoration Project.

NSTec Geotechnical Sciences Group

2007-03-01T23:59:59.000Z

155

Insights Into the P-To-Q Conversion in the Catalytic Cycle of Methane Monooxygenase From a Synthetic Model System  

DOE Green Energy (OSTI)

For the catalytic cycle of soluble methane monooxygenase (sMMO), it has been proposed that cleavage of the O-O bond in the ({mu}-peroxo)diiron(III) intermediate P gives rise to the diiron(IV) intermediate Q with an Fe{sub 2}({mu}-O){sub 2} diamond core, which oxidizes methane to methanol. As a model for this conversion, ({mu}-oxo) diiron(III) complex 1 ([Fe{sup III}{sub 2}({mu}-O)({mu}-O{sub 2}H{sub 3})(L){sub 2}]{sup 3+}, L = tris(3,5-dimethyl-4-methoxypyridyl-2-methyl)amine) has been treated consecutively with one eq of H{sub 2}O{sub 2} and one eq of HClO{sub 4} to form 3 ([Fe{sup IV}{sub 2}({mu}-O){sub 2}(L){sub 2}]{sup 4+}). In the course of this reaction a new species, 2, can be observed before the protonation step; 2 gives rise to a cationic peak cluster by ESI-MS at m/z 1,399, corresponding to the [Fe{sub 2}O{sub 3}L{sub 2}H](OTf){sub 2}{sup +} ion in which 1 oxygen atom derives from 1 and the other two originate from H{sub 2}O{sub 2}. Moessbauer studies of 2 reveal the presence of two distinct, exchange coupled iron(IV) centers, and EXAFS fits indicate a short Fe-O bond at 1.66 {angstrom} and an Fe-Fe distance of 3.32 {angstrom}. Taken together, the spectroscopic data point to an HO-Fe{sup IV}-O-Fe{sup IV} = O core for 2. Protonation of 2 results in the loss of H{sub 2}O and the formation of 3. Isotope labeling experiments show that the [Fe{sup IV}{sub 2}({mu}-O){sub 2}] core of 3 can incorporate both oxygen atoms from H{sub 2}O{sub 2}. The reactions described here serve as the only biomimetic precedent for the conversion of intermediates P to Q in the sMMO reaction cycle and shed light on how a peroxodiiron(III) unit can transform into an [Fe{sup IV}{sub 2}({mu}-O){sub 2}] core.

Xue, G.; Fiedler, A.T.; Martinho, M.; Munck, E.; Que, L.; Jr.

2009-05-28T23:59:59.000Z

156

A Mechanistic Treatment of the Dominant Soil Nitrogen Cycling Processes: Model Development, Testing, and Application  

SciTech Connect

The development and initial application of a mechanistic model (TOUGHREACT-N) designed to characterize soil nitrogen (N) cycling and losses are described. The model couples advective and diffusive nutrient transport, multiple microbial biomass dynamics, and equilibrium and kinetic chemical reactions. TOUGHREACT-N was calibrated and tested against field measurements to assess pathways of N loss as either gas emission or solute leachate following fertilization and irrigation in a Central Valley, California, agricultural field as functions of fertilizer application rate and depth, and irrigation water volume. Our results, relative to the period before plants emerge, show that an increase in fertilizer rate produced a nonlinear response in terms of N losses. An increase of irrigation volume produced NO{sub 2}{sup -} and NO{sub 3}{sup -} leaching, whereas an increase in fertilization depth mainly increased leaching of all N solutes. In addition, nitrifying bacteria largely increased in mass with increasing fertilizer rate. Increases in water application caused nitrifiers and denitrifiers to decrease and increase their mass, respectively, while nitrifiers and denitrifiers reversed their spatial stratification when fertilizer was applied below 15 cm depth. Coupling aqueous advection and diffusion, and gaseous diffusion with biological processes, closely captured actual conditions and, in the system explored here, significantly clarified interpretation of field measurements.

Riley, William; Maggi, F.; Gu, C.; Riley, W.J.; Hornberger, G.M.; Venterea, R.T.; Xu, T.; Spycher, N.; Steefel, C.; Miller, N.L.; Oldenburg, C.M.

2008-05-01T23:59:59.000Z

157

Sensitivity of 0–12-h Warm-Season Precipitation Forecasts over the Central United States to Model Initialization  

Science Conference Proceedings (OSTI)

Sensitivity of 0–12-h warm-season precipitation forecasts to atmospheric initial conditions, including those from different large-scale model analyses and from rapid cycled (RC) three-dimensional variational data assimilations (3DVAR) with and ...

Juanzhen Sun; Stanley B. Trier; Qingnong Xiao; Morris L. Weisman; Hongli Wang; Zhuming Ying; Mei Xu; Ying Zhang

2012-08-01T23:59:59.000Z

158

Orogenic Propagating Precipitation Systems over the United States in a Global Climate Model with Embedded Explicit Convection  

Science Conference Proceedings (OSTI)

In the lee of major mountain chains worldwide, diurnal physics of organized propagating convection project onto seasonal and climate time scales of the hydrologic cycle, but this phenomenon is not represented in conventional global climate models (...

Michael S. Pritchard; Mitchell W. Moncrieff; Richard C. J. Somerville

2011-08-01T23:59:59.000Z

159

Simulations of Present and Future Climates in the Western United States with Four Nested Regional Climate Models  

Science Conference Proceedings (OSTI)

In this paper, the authors analyze simulations of present and future climates in the western United States performed with four regional climate models (RCMs) nested within two global ocean–atmosphere climate models. The primary goal here is to ...

P. B. Duffy; R. W. Arritt; J. Coquard; W. Gutowski; J. Han; J. Iorio; J. Kim; L.-R. Leung; J. Roads; E. Zeledon

2006-03-01T23:59:59.000Z

160

Life-cycle cost analysis project. Final report  

Science Conference Proceedings (OSTI)

An investigation was conducted to demonstrate the impact of life-cycle costing in Ohio's residential building sector. Typical single-family, townhouse, and multifamily housing units were modeled using sophisticated computer programs to predict annual energy comsumption. Energy conservation techniques were applied to the typical units and the resulting utility savings were computed. Installed costs were estimated for each energy conservation technique.

Davies, G.R.; Temming, S.J.

1980-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

ON CALCULATING THE TRANSFER OF CARBON-13 IN RESERVOIR MODELS OF THE CARBON CYCLE  

E-Print Network (OSTI)

7. Keeling. C. D. 1973. The carbon dioxide cycle: reservoirexchange of atmospheric carbon dioxide with the oceans andmodel to study the carbon dioxide exchange in nature. Tellus

Tans, Pieter P.

2013-01-01T23:59:59.000Z

162

Modeling the Performance, Emissions, and Costs of Texaco Gasifier-Based Integrated Gasification Combined Cycle Systems.  

E-Print Network (OSTI)

??Integrated Gasification Combined Cycle (IGCC) systems are an advanced power generation concept with the flexibility to use coal, heavy oils, petroleum coke, biomass, and waste… (more)

Akunuri, Naveen

1999-01-01T23:59:59.000Z

163

Development of 20 IEER Rooftop Units System Modeling and Building Energy Simulations  

Science Conference Proceedings (OSTI)

Based on detailed steady-state system and component modeling, we developed a rooftop unit system design, which is able to achieve IEER (Integrated Energy Efficiency Ratio) higher than 20. We modeled fin-&-tube and micro-channel heat exchangers using segment-to-segment approach, and use AHRI 10-coefficient compressor map to simulate compressor performance. The system modeling is based on a component-based modeling approach, which facilitates flexible simulation of complicated system configurations. Starting with a baseline system having IEER of 16.6, we extensively investigated numerous technical options, i.e. varying compressor sizes, heat exchanger fin densities, fin-&-tube or micro-channel heat exchanger, suction line heat exchanger, desiccant wheel, tandem compressor, variable-speed compressor, and condenser evaporative pre-cooling; and developed an innovative system configuration combining a tandem compression system with a variable-speed compression system. The combined system can achieve high IEER as well as process the outdoor ventilation air over an extensive range. We successfully evaluated the design concept for a 20-ton (70.4 kW) unit as well as a 10-ton (35.2 kW) unit. All the selected components are readily accessible on the market, and we validated the performance predictions against existing Rooftop Unit (RTU) products at the rating condition. This paper illustrates a potentially cost-effective high IEER RTU design. In addtion, we conducted extensive building energy simulations using EnergyPlus to predict seasonal energy saving potentials and peak power reductions using the High IEER RTU in sixteen US cities, in comparison to a RTU with a minimum efficiency.

Shen, Bo [ORNL; Rice, C Keith [ORNL; Vineyard, Edward [Oak Ridge National Laboratory (ORNL)

2013-01-01T23:59:59.000Z

164

A probabilistic tornado wind hazard model for the continental United States  

SciTech Connect

A probabilistic tornado wind hazard model for the continental United States (CONUS) is described. The model incorporates both aleatory (random) and epistemic uncertainties associated with quantifying the tornado wind hazard parameters. The temporal occurrences of tornadoes within the continental United States (CONUS) is assumed to be a Poisson process. A spatial distribution of tornado touchdown locations is developed empirically based on the observed historical events within the CONUS. The hazard model is an aerial probability model that takes into consideration the size and orientation of the facility, the length and width of the tornado damage area (idealized as a rectangle and dependent on the tornado intensity scale), wind speed variation within the damage area, tornado intensity classification errors (i.e.,errors in assigning a Fujita intensity scale based on surveyed damage), and the tornado path direction. Epistemic uncertainties in describing the distributions of the aleatory variables are accounted for by using more than one distribution model to describe aleatory variations. The epistemic uncertainties are based on inputs from a panel of experts. A computer program, TORNADO, has been developed incorporating this model; features of this program are also presented.

Hossain, Q; Kimball, J; Mensing, R; Savy, J

1999-04-19T23:59:59.000Z

165

World nuclear fuel cycle requirements 1991  

Science Conference Proceedings (OSTI)

The nuclear fuel cycle consists of mining and milling uranium ore, processing the uranium into a form suitable for generating electricity, burning'' the fuel in nuclear reactors, and managing the resulting spent nuclear fuel. This report presents projections of domestic and foreign requirements for natural uranium and enrichment services as well as projections of discharges of spent nuclear fuel. These fuel cycle requirements are based on the forecasts of future commercial nuclear power capacity and generation published in a recent Energy Information Administration (EIA) report. Also included in this report are projections of the amount of spent fuel discharged at the end of each fuel cycle for each nuclear generating unit in the United States. The International Nuclear Model is used for calculating the projected nuclear fuel cycle requirements. 14 figs., 38 tabs.

Not Available

1991-10-10T23:59:59.000Z

166

Diagnosing the Annual Cycle of the Equatorial Undercurrent in the Atlantic Ocean from a General Circulation Model  

Science Conference Proceedings (OSTI)

Ten-year-long output series from a general circulation model forced by daily realistic winds are used to analyze the annual cycle of the Equatorial Undercurrent (EUC) in the Atlantic Ocean. Two well-defined transport maxima are found: One, ...

M. Arhan; A. M. Treguier; B. Bourlès; S. Michel

2006-08-01T23:59:59.000Z

167

Comparison of the Diurnal Precipitation Cycle in Convection-Resolving and Non-Convection-Resolving Mesoscale Models  

Science Conference Proceedings (OSTI)

The diurnal cycles of rainfall in 5-km grid-spacing convection-resolving and 22-km grid-spacing non-convection-resolving configurations of the Weather Research and Forecasting (WRF) model are compared to see if significant improvements can be ...

Adam J. Clark; William A. Gallus Jr.; Tsing-Chang Chen

2007-10-01T23:59:59.000Z

168

Estimates of the Global Water Budget and Its Annual Cycle Using Observational and Model Data  

Science Conference Proceedings (OSTI)

A brief review is given of research in the Climate Analysis Section at NCAR on the water cycle. Results are used to provide a new estimate of the global hydrological cycle for long-term annual means that includes estimates of the main reservoirs ...

Kevin E. Trenberth; Lesley Smith; Taotao Qian; Aiguo Dai; John Fasullo

2007-08-01T23:59:59.000Z

169

Modeling the Long-Term Market Penetration of Wind in the United States  

DOE Green Energy (OSTI)

This paper presents an overview of the Wind Deployment Systems Model (WinDS). WinDS is a multiregional, multitime-period, Geographic Information System (GIS), and linear programming model of capacity expansion in the electric sector of the United States. WinDS is designed to address the principal market issues related to the penetration of wind energy technologies into the electric sector. These principal market issues include access to and cost of transmission, and the intermittency of wind power. WinDS addresses these issues through a highly discretized regional structure, explicit accounting for the variability in wind output over time, and consideration of ancillary services requirements and costs.

Short, W.; Blair, N.; Heimiller, D.; Singh, V.

2003-07-01T23:59:59.000Z

170

Kinetic modeling of the hydrotreatment of light cycle oil/diesel  

E-Print Network (OSTI)

A rigorous kinetic model of hydrodesulfurization (HDS) of complex mixtures such as light cycle oil (LCO) or diesel has been developed. An experimental setup was constructed to investigate the hydrotreatment of complex mixtures. The hydrodesulfurization of LCO on a commercial CoMo/Al2O3 (IMP) catalyst was investigated in a Robinson Mahoney perfectly mixed flow stationary basket reactor. An experimental investigation of the HDS of the dibenzothiophene (DBT) and substituted dibenzothiophenes in the LCO was carried out at temperatures between 290 and 330°C, space time for dibenzothiophene (W/F0 DBT) between 1000 and 6500 kgcat-h/kmol, and H2/HC molar ratio constant of 2.8. To avoid having to deal with a huge number of parameters in the model, a methodology based on structural contributions was applied. DENs and DENt are the denominators of the Hougen-Watson rate expressions for hydrodesulfurization of dibenzothiophene (DBT) and methyl-substituted dibenzothiophenes contained in the LCO. Both denominators comprise the concentration of all adsorbing species of the LCO multiplied by their adsorption equilibrium constants. The estimation of the denominators DENs and DENt was performed using the Levenberg-Marquardt algorithm and the results in terms of conversion for DBT, biphenyl and cyclohexylbenzene obtained in the hydrodesulfurization of the LCO. The evolution of DENs and DENt values with the composition was calculated for each LCO experiment. Structural contributions were taken from Vanrysselberghe and Froment for hydrogenolysis and hydrogenation of methyl-substituted dibenzothiophenes with a significant reduction in the number of parameters to be estimated in the HDS of the LCO. The multiplication factors, fsDBT, which are products of structural contributions for hydrogenolysis and hydrogenation of the mono- and dimethyl-dibenzothiophenes were also taken from Vanrysselberghe and Froment. These multiplication factors are based on experimental results with model components such as DBT, 4-Methyl dibenzothiophene and 4,6-Dimethyl dibenzothiophene. The results obtained in the modeling are in good agreement with the experimental data because the model reproduces very well the observed total conversions of DBT, conversions of DBT into biphenyl and conversions of DBT into cyclohexylbenzene as a function of temperature.

Castaneda-Lopez, Luis Carlos

2006-12-01T23:59:59.000Z

171

A Hydrostratigraphic Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat-Climax Mine, Lincoln and Nye Counties, Nevada  

SciTech Connect

A new three-dimensional hydrostratigraphic framework model for the Yucca Flat-Climax Mine Corrective Action Unit was completed in 2005. The model area includes Yucca Flat and Climax Mine, former nuclear testing areas at the Nevada Test Site, and proximal areas. The model area is approximately 1,250 square kilometers in size and is geologically complex. Yucca Flat is a topographically closed basin typical of many valleys in the Basin and Range province. Faulted and tilted blocks of Tertiary-age volcanic rocks and underlying Proterozoic and Paleozoic sedimentary rocks form low ranges around the structural basin. During the Cretaceous Period a granitic intrusive was emplaced at the north end of Yucca Flat. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the basin. These were integrated using EarthVision? software to develop the 3-dimensional hydrostratigraphic framework model. Fifty-six stratigraphic units in the model area were grouped into 25 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the alluvial section into 3 hydrostratigraphic units including 2 aquifers and 1 confining unit. The volcanic units in the model area are organized into 13 hydrostratigraphic units that include 8 aquifers and 5 confining units. The underlying pre-Tertiary rocks are divided into 7 hydrostratigraphic units, including 3 aquifers and 4 confining units. Other units include 1 Tertiary-age sedimentary confining unit and 1 Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units (''layers'' in the model) along with the major structural features (i.e., faults). The model incorporates 178 high-angle normal faults of Tertiary age and 2 low-angle thrust faults of Mesozoic age. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Five of these alternatives were developed so they could be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area subproject of the Environmental Restoration Project.

Geotechnical Sciences Group Bechtel Nevada

2006-01-01T23:59:59.000Z

172

THE ALLISON UNIT CO{sub 2}-ECBM PILOT: A RESERVOIR MODELING STUDY  

SciTech Connect

In October, 2000, the United States Department of Energy, through contractor Advanced Resources International (ARI), launched a multi-year government-industry research & development collaboration called the Coal-Seq project. The Coal-Seq project is investigating the feasibility of carbon dioxide (CO{sub 2}) sequestration in deep, unmineable coalseams by performing detailed reservoir studies of two enhanced coalbed methane (ECBM) recovery field projects in the San Juan basin. The two sites are the Allison Unit, operated by Burlington Resources, and into which CO{sub 2} is being injected, and the Tiffany Unit, operating by BP America, into which nitrogen (N{sub 2}) is being injected (the interest in understanding the N{sub 2}-ECBM process has important implications for CO{sub 2} sequestration via flue-gas injection). The purposes of the field studies are to understand the reservoir mechanisms of CO{sub 2} and N{sub 2} injection into coalseams, demonstrate the practical effectiveness of the ECBM and sequestration processes, demonstrate an engineering capability to model them, and to evaluate sequestration economics. In support of these efforts, laboratory and theoretical studies are also being performed to understand and model multicomponent isotherm behavior, and coal permeability changes due to swelling with CO{sub 2} injection. This report describes the results of an important component of the overall project, the Allison Unit reservoir study. The Allison Unit is located in the northern New Mexico portion of the prolific San Juan basin. The study area consists of 16 methane production wells, 4 CO{sub 2} injection wells, and one pressure observation well. The field originally began production in July 1989, and CO{sub 2} injection operations for ECBM purposes commenced in April, 1995. CO{sub 2} injection was suspended in August, 2001, to evaluate the results of the pilot. In this study, a detailed reservoir characterization of the field was developed, the field history was matched using the COMET2 reservoir simulator, and future field performance was forecast under various operating conditions. Based on the results of the study, the following conclusions have been drawn: (1) The injection of CO{sub 2} at the Allison Unit has resulted in incremental methane recovery over estimated ultimate primary recovery, in a proportion of approximately one volume of methane for every three volumes of CO{sub 2} injected. (2) The study area was successfully modeled with ARI's COMET2 model. However, aspects of the model remain uncertain, such as producing and injecting bottomhole pressures, CO{sub 2} content profiles of the produced gas, and the pressure at the observation well. (3) There appears to be clear evidence of significant coal permeability reduction with CO{sub 2} injection. This permeability reduction, and the associated impact on CO{sub 2} injectivity, compromised incremental methane recoveries and project economics. Finding ways to overcome and/or prevent this effect is therefore an important topic for future research. (4) From a CO{sub 2} sequestration standpoint, the incremental methane recoveries (based solely on the conditions encountered at the Allison Unit), can provide a meaningful offset to CO{sub 2} separation, capture and transportation costs, on the order of $2-5/ton of CO{sub 2}.

Scott Reeves; Anne Taillefert; Larry Pekot; Chris Clarkson

2003-02-01T23:59:59.000Z

173

Life-Cycle Energy Use and Greenhouse Gas Emission Implicaitons of Brazilian Sugarcane Ethanol Simulated with the GREET Model  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Life-Cycle Energy Use and Greenhouse Gas Emission Implications of Life-Cycle Energy Use and Greenhouse Gas Emission Implications of Brazilian Sugarcane Ethanol Simulated with the GREET Model Michael Wang*, May Wu, Hong Huo and Jiahong Liu Center for Transportation Research, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA. *Contact author: Tel: +1 (630) 252 2819 Fax: +1 (630) 252 3443 Email: mqwang@anl.gov In International Sugar Journal 2008, Vol. 110, No. 1317 ABSTRACT By using data available in the open literature, we expanded the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model developed by Argonne National Laboratory to include Brazilian-grown sugarcane ethanol. With the expanded GREET model, we examined the well-to-wheels (WTW) energy use and

174

The development of a life cycle cost model for railroad tunnels  

E-Print Network (OSTI)

Today, Life Cycle Costing is one of the most popular ways of assessing a project's or an investment's worth to a company. This method of assessment is often applied to all stages of a investment's lifecycle, starting from ...

Angeles, Jon Virgil V

2011-01-01T23:59:59.000Z

175

Modeling Potential Equilibrium States of Vegetation and Terrestrial Water Cycle of Mesoamerica under Climate Change Scenarios  

Science Conference Proceedings (OSTI)

The likelihood and magnitude of the impacts of climate change on potential vegetation and the water cycle in Mesoamerica is evaluated. Mesoamerica is a global biodiversity hotspot with highly diverse topographic and climatic conditions and is ...

Pablo Imbach; Luis Molina; Bruno Locatelli; Olivier Roupsard; Gil Mahé; Ronald Neilson; Lenin Corrales; Marko Scholze; Philippe Ciais

2012-04-01T23:59:59.000Z

176

Prediction of the Life Cycle of a Supertyphoon with a High-Resolution Global Model  

Science Conference Proceedings (OSTI)

The life cycle of Supertyphoon Hope (1979) from a tropical depression stage to intensification and its eventual weakening after land-fall, some 6 days later, is followed in a real-data numerical prediction experiment. The predictions are carried ...

T. N. Krishnamurti; D. Oosterhof

1989-10-01T23:59:59.000Z

177

Grid-BGC: a grid-enabled terrestrial carbon cycle modeling system  

Science Conference Proceedings (OSTI)

Grid-BGC is a Grid-enabled terrestrial biogeochemical cycle simulator collaboratively developed by the National Center for Atmospheric Research (NCAR) and the University of Colorado (CU) with funding from NASA. The primary objective of the project is ...

Jason Cope; Craig Hartsough; Peter Thornton; Henry Tufo; Nathan Wilhelmi; Matthew Woitaszek

2005-08-01T23:59:59.000Z

178

Investigation of the Summer Climate of the Contiguous United States and Mexico Using the Regional Atmospheric Modeling System (RAMS). Part I: Model Climatology (1950–2002)  

Science Conference Proceedings (OSTI)

Fifty-three years of the NCEP–NCAR Reanalysis I are dynamically downscaled using the Regional Atmospheric Modeling System (RAMS) to generate a regional climate model (RCM) climatology of the contiguous United States and Mexico. Data from the RAMS ...

Christopher L. Castro; Roger A. Pielke Sr.; Jimmy O. Adegoke

2007-08-01T23:59:59.000Z

179

Development and application of the EPIC model for carbon cycle, greenhouse-gas mitigation, and biofuel studies  

Science Conference Proceedings (OSTI)

This chapter provides a comprehensive review of the EPIC model in relation to carbon cycle, greenhouse-gas mitigation, and biofuel applications. From its original capabilities and purpose (i.e., quantify the impacts or erosion on soil productivity), the EPIC model has evolved into a comprehensive terrestrial ecosystem model for simulating with more or less process-level detail many ecosystem processes such as weather, hydrology, plant growth and development, carbon cycle (including erosion), nutrient cycling, greenhouse-gas emissions, and the most complete set of manipulations that can be implemented on a parcel of land (e.g. tillage, harvest, fertilization, irrigation, drainage, liming, burning, pesticide application). The chapter also provides details and examples of the latest efforts in model development such as the coupled carbon-nitrogen model, a microbial denitrification model with feedback to the carbon decomposition model, updates on calculation of ecosystem carbon balances, and carbon emissions from fossil fuels. The chapter has included examples of applications of the EPIC model in soil carbon sequestration, net ecosystem carbon balance, and biofuel studies. Finally, the chapter provides the reader with an update on upcoming improvements in EPIC such as the additions of modules for simulating biochar amendments, sorption of soluble C in subsoil horizons, nitrification including the release of N2O, and the formation and consumption of methane in soils. Completion of these model development activities will render an EPIC model with one of the most complete representation of biogeochemical processes and capable of simulating the dynamic feedback of soils to climate and management in terms not only of transient processes (e.g., soil water content, heterotrophic respiration, N2O emissions) but also of fundamental soil properties (e.g. soil depth, soil organic matter, soil bulk density, water limits).

Izaurralde, Roberto C.; Mcgill, William B.; Williams, J.R.

2012-06-01T23:59:59.000Z

180

Glass Composition Constraint Recommendations for Use in Life-Cycle Mission Modeling  

Science Conference Proceedings (OSTI)

The component concentration limits that most influence the predicted Hanford life-cycle HLW glass volume by HTWOS were re-evaluated. It was assumed that additional research and development work in glass formulation and melter testing would be performed to improve the understanding of component effects on the processability and product quality of these HLW glasses. Recommendations were made to better estimate the potential component concentration limits that could be applied today while technology development is underway to best estimate the volume of HLW glass that will eventually be produced at Hanford. The limits for concentrations of P2O5, Bi2O3, and SO3 were evaluated along with the constraint used to avoid nepheline formation in glass. Recommended concentration limits were made based on the current HLW glass property models being used by HTWOS (Vienna et al. 2009). These revised limits are: 1) The current ND should be augmented by the OB limit of OB ? 0.575 so that either the normalized silica (NSi) is less that the 62% limit or the OB is below the 0.575 limit. 2) The mass fraction of P2O5 limit should be revised to allow for up to 4.5 wt%, depending on CaO concentrations. 3) A Bi2O3 concentration limit of 7 wt% should be used. 4) The salt accumulation limit of 0.5 wt% SO3 may be increased to 0.6 wt%. Again, these revised limits do not obviate the need for further testing, but make it possible to more accurately predict the impact of that testing on ultimate HLW glass volumes.

McCloy, John S.; Vienna, John D.

2010-05-03T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Microsoft Word - UPDATE 5 - Units 1,2 + base load unit.doc  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5 to: 5 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant Modeling Cycling Units 1, 2 plus One Baseload Unit ENSR Corporation January 6, 2006 Document Number 10350-002-420 (Update 5) January, 2006 1-1 1.0 INTRODUCTION This report describes dispersion modeling performed for simultaneous operation of one baseload unit and two cycling units at Mirant's Potomac River Generating Station (PRGS). This mode of operation is also referred to as Option A in Mirant Potomac River LLC's December 30, 2005 letter to the U.S. Department of Energy regarding District of Columbia Public Service Commission, Docket No. EO-05- 01. The modeling was performed according to the Protocol approved by the Virginia Department of

182

Edgeworth cycles revisited  

E-Print Network (OSTI)

Some gasoline markets exhibit remarkable price cycles, where price spikes are followed by a series of small price declines: a pattern consistent with a model of Edgeworth cycles described by Maskin and Tirole. We extend ...

Doyle, Joseph J.

183

Verti Jack Pumping Unit evaluation  

Science Conference Proceedings (OSTI)

The Verti Jack Pumping Unit was tested primarily to establish the energy comsumption efficiency of the unit as compared with that of conventional pumping unit. Before the unit was field tested, extensive static testing was performed to determine the effect of the counterbalance system throughout the operational cycle. The field test included comparing the performance of the Verti Jack Unit and conventional pump jacks - a Bethlehem 16 and Cabot 25 pumping unit. The Verti Jack unit was operated at four different pumping conditions. The Verti Jack unit peformed satisfactorily during the testing. Only minor problems that could not be attributed to the design or operation of the unit were encountered. Changing the stroke length was difficult in the field, but such operational problems were expected in operating the first phototype and can be corrected on future models. During the higher pumping rate tests of the Verti Jack unit, the well ceased to deliver fluid quantities at rates adequate to the pumping rate. These data are shown in table 8. Therefore, evaluation data are based on theoretical pump performance and are presented in table 9. The data show that the Verti Jack is more efficient than the conventional units tested. The most direct comparison was the Verti Jack test at 36-inch stroke and 12 1/2 strokes per minute versus the Cabot unit at 37-inch stroke and 12 strokes per minute. In the comparison the Verti Jack operated about 24 percent more efficiently than the Cabot unit. Comparing the summation of all Verti Jack tests with that of all conventional unit tests, the Verti Jack operated about 15 percent more efficiently. Compared to the Cabot unit only, the Verti Jack was about 17 percent more energy efficient. 13 figs., 12 tabs.

Porter, R.; Spence, K.

1985-11-01T23:59:59.000Z

184

Multiscale Interactions in the Life Cycle of a Tropical Cyclone Simulated in a Global Cloud-System-Resolving Model. Part II: System-Scale and Mesoscale Processes  

Science Conference Proceedings (OSTI)

The life cycle of Tropical Storm Isobel was simulated reasonably well in the Nonhydrostatic Icosahedral Atmospheric Model (NICAM), a global cloud-system-resolving model. The evolution of the large-scale circulation and the storm-scale structure ...

Hironori Fudeyasu; Yuqing Wang; Masaki Satoh; Tomoe Nasuno; Hiroaki Miura; Wataru Yanase

2010-12-01T23:59:59.000Z

185

Parallel Simulation for a Fish Schooling Model on a General-Purpose Graphics Processing Unit  

E-Print Network (OSTI)

Purpose Graphics Processing Unit Hong Li Department ofof graphics processing units is well-suited to this task. Wehow a Graphics Pro- cessor Unit (GPU) can be used to very

Li, Hong; Kolpas, Allison; Petzold, Linda; Moehlis, J

2009-01-01T23:59:59.000Z

186

Impact of Bias-Correction Type and Conditional Training on Bayesian Model Averaging over the Northeast United States  

Science Conference Proceedings (OSTI)

The performance of a multimodel ensemble over the northeast United States is evaluated before and after applying bias correction and Bayesian model averaging (BMA). The 13-member Stony Brook University (SBU) ensemble at 0000 UTC is combined with ...

Michael J. Erickson; Brian A. Colle; Joseph J. Charney

2012-12-01T23:59:59.000Z

187

Application of the Dynamic Mercury Cycling Model (D-MCM) to the Robert C. Byrd Pool, Ohio River  

Science Conference Proceedings (OSTI)

This Technical Update describes the ongoing application of the Electric Power Research Institute’s (EPRI’s) Dynamic Mercury Cycling Model (D-MCM) to the Ohio River. The study focuses on mercury sources, sinks and bioaccumulation in the Robert C. Byrd Pool in the Ohio River, including the contribution of nearby coal-fired facilities to fish mercury (Hg) concentrations.BackgroundMonitoring of Hg concentrations in sport fish in the Ohio River has shown generally low ...

2012-12-12T23:59:59.000Z

188

Characteristics of Drought and Persistent Wet Spells over the United States in the Atmosphere–Land–Ocean Coupled Model Experiments  

Science Conference Proceedings (OSTI)

Atmosphere–land–ocean coupled model simulations are examined to diagnose the ability of models to simulate drought and persistent wet spells over the United States. A total of seven models are selected for this study. They are three versions of ...

Kingtse C. Mo; Lindsey N. Long; Jae-Kyung E. Schemm

2012-09-01T23:59:59.000Z

189

Unit physics performance of a mix model in Eulerian fluid computations  

SciTech Connect

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

190

Design, optimization and predictions of a coupled model of the cell cycle, circadian clock, DNA repair system, irinotecan metabolism and exposure control under temporal logic constraints  

Science Conference Proceedings (OSTI)

In systems biology, the number of available models of cellular processes has increased rapidly, but re-using models in different contexts or for different questions remains a challenging issue. In this paper, we study the coupling of different models ... Keywords: Cell cycle, Constraint solving, DNA damage, Irinotecan, Model checking, Model coupling, Parameter learning, Temporal logic

Elisabetta De Maria; François Fages; Aurélien Rizk; Sylvain Soliman

2011-05-01T23:59:59.000Z

191

Modeling and optimization of geothermal power plants using the binary fluid cycle  

SciTech Connect

A computer simulation of a binary fluid cycle power plant for use with geothermal energy sources, and the subsequent optimization of this power plant type over a range of geothermal source conditions are described. The optimization technique employed for this analysis was based upon the principle of maximum use of geothermal energy.

Walter, R.A.

1976-09-01T23:59:59.000Z

192

System dynamics modelling of product carbon footprint life cycles for collaborative green supply chains  

Science Conference Proceedings (OSTI)

Governments, environmental groups and industry associations are reducing greenhouse gas emissions to insure environmental sustainability. Manufacturing plays an important role in economic development but is a main cause of global warming since production ... Keywords: economic input–output life cycle assessment, mass customisation, product carbon footprint, system dynamics

AmyJ. C. Trappey; CharlesV. Trappey; Chih-Tung Hsiao; JerryJ. R. Ou; Chin-Tsung Chang

2012-10-01T23:59:59.000Z

193

Modeling and experimental results for condensing supercritical CO2 power cycles.  

Science Conference Proceedings (OSTI)

This Sandia supported research project evaluated the potential improvement that 'condensing' supercritical carbon dioxide (S-CO{sub 2}) power cycles can have on the efficiency of Light Water Reactors (LWR). The analytical portion of research project identified that a S-CO{sub 2} 'condensing' re-compression power cycle with multiple stages of reheat can increase LWR power conversion efficiency from 33-34% to 37-39%. The experimental portion of the project used Sandia's S-CO{sub 2} research loop to show that the as designed radial compressor could 'pump' liquid CO{sub 2} and that the gas-cooler's could 'condense' CO{sub 2} even though both of these S-CO{sub 2} components were designed to operate on vapor phase S-CO{sub 2} near the critical point. There is potentially very high value to this research as it opens the possibility of increasing LWR power cycle efficiency, above the 33-34% range, while lowering the capital cost of the power plant because of the small size of the S-CO{sub 2} power system. In addition it provides a way to incrementally build advanced LWRs that are optimally designed to couple to S-CO{sub 2} power conversion systems to increase the power cycle efficiency to near 40%.

Wright, Steven Alan; Conboy, Thomas M.; Radel, Ross F.; Rochau, Gary Eugene

2011-01-01T23:59:59.000Z

194

A generalized multistage optimization modeling framework for life cycle assessment-based integrated solid waste management  

Science Conference Proceedings (OSTI)

Solid waste management (SWM) is an integral component of civil infrastructure and the global economy, and is a growing concern due to increases in population, urbanization, and economic development. In 2011, 1.3 billion metric tons of municipal solid ... Keywords: Decision support, Life cycle assessment, Multi-stage, Optimization, Solid waste

James W. Levis, Morton A. Barlaz, Joseph F. Decarolis, S. Ranji Ranjithan

2013-12-01T23:59:59.000Z

195

Generation Maintenance Applications Center: Combined-Cycle Combustion Turbine Steam Bypass Model Maintenance Guide  

Science Conference Proceedings (OSTI)

BackgroundCombustion turbine combined-cycle (CTCC) facilities use various systems and components that are unique to this type of power generation plants and are not typically found in a nuclear or fossil power plant. As such, current CTCC facility owners’ use of the Electric Power ...

2013-12-14T23:59:59.000Z

196

Geothermal completion technology life cycle cost model (GEOCOM). Volume I. Final report. Volume II. User instruction manual  

DOE Green Energy (OSTI)

Just as with petroleum wells, drilling and completing a geothermal well at minimum original cost may not be the most cost-effective way to exploit the resource. The impacts of the original completion activities on production and costs later in the life of the well must also be considered. In order to evaluate alternate completion and workover technologies, a simple computer model has been developed to compare total life-cycle costs for a geothermal well to total production or injection. Volume I discusses the mechanics of the model and then presents detailed results from its application to different completion and workover questions. Volume II is the user instruction manual.

Anderson, E.R.; Hoessel, W.C.; Mansure, A.J.; McKissen, P.

1982-07-01T23:59:59.000Z

197

NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005  

Open Energy Info (EERE)

NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 Baseline Model Jump to: navigation, search Tool Summary LAUNCH TOOL Name: NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 Baseline Model Agency/Company /Organization: National Energy Technology Laboratory Sector: Energy Topics: Baseline projection, GHG inventory Resource Type: Software/modeling tools Website: www.netl.doe.gov/energy-analyses/refshelf/results.asp?ptype=Models/Too References: NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 Baseline Model [1] NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 Baseline Model This model calculates the 2005 national average life cycle greenhouse gas emissions for petroleum-based fuels sold or distributed in the United

198

Modeling the Effect of Chlorine Emissions on Ozone Levels over the Eastern United States  

E-Print Network (OSTI)

This paper presents model estimates of the effect of chlorine emissions on atmospheric ozone concentrations in the eastern United States. The model included anthropogenic molecular chlorine emissions, anthropogenic hypochlorous acid emissions from cooling towers and swimming pools, and chlorine released from sea-salt aerosols. The release of chlorine emissions from sea-salt aerosols was modeled using heterogeneous reactions involving chloride ions in aerosols and three gas-phase species. The gas-phase chlorine chemistry was combined with the Carbon Bond Mechanism and incorporated into the Community Multiscale Air Quality modeling system. Air quality model simulations were performed for July 2001 and the results obtained with and without chlorine emissions were analyzed. When chlorine emissions were included in the model, ozone concentrations increased in the Houston, Texas, and New York–New Jersey areas. The daily maximum 1-h ozone concentrations increased by up to 12 parts per billion by volume (ppbv) in the Houston area and 6 ppbv in the New York–New Jersey area. The daily maximum 8-h ozone concentrations increased by up to 8 ppbv in the Houston area and 4 ppbv in the New York–New Jersey area. The monthly average daily maximum 1-h ozone concentration increased by up to 3 ppbv in the Houston area, but the increases in the monthly average daily maximum 1-h ozone concentration in the New York–New Jersey area were small. Chlorine emissions and chemistry enhanced the volatile organic compound oxidation rates and, thereby, increased the ozone production rate. 1.

Golam Sarwar; Prakash; V. Bhave

2006-01-01T23:59:59.000Z

199

Public data sources and modeling of district heating in the United States  

DOE Green Energy (OSTI)

A methodology for computerized modelling of hot water district heating service in any urban area in the United States is described. It is distinguished by the depth and breadth of its data bases, the ease with which any urban market can be analyzed and the wide variety of intermediate information which is obtained. Real housing and employment data, canvassed for the entire nation and made available on a very small area basis, are conjoined with local climate profiles, labor costs, land use intensity factors, fuel prices and fuel use profiles to generate profiles of heating demands and markets for district heat. This characterization of residential and commercial space and water heating demands permits a system design and costing of piping systems for distribution of hot water, subject to any penetration constraints imposed. A minimal number of assumptions are needed to generate these products from the data bases, many of which were generated in the public domain for other purposes.

Karkheck, J.; Tessmer, R.G., Jr.

1979-01-01T23:59:59.000Z

200

Unit physics testing of a mix model in an eulerian fluid computation  

Science Conference Proceedings (OSTI)

A K-L turbulence mix model driven with a drag-buoyancy source term is tested in an Eulerian code in a series of basic unit-physics tests, as part of a mix validation milestone. The model and the closure coefficient values are derived in the work of Dimonte-Tipton [D-T] in Phys.Flu.18, 085101 (2006), and many of the test problems were reported there, where the mix model operated in Lagrange computations. The drag-buoyancy K-L mix model was implemented within the Eulerian code framework by A.J. Scannapieco. Mix model performance is evaluated in terms of mix width growth rates compared to experiments in select regimes. Results in our Eulerian code are presented for several unit-physics I-D test problems including the decay of homogeneous isotropic turbulence (HIT), Rayleigh-Taylor (RT) unstable mixing, shock amplification of initial turbulence, Richtmyer-Meshkov (RM) mixing in several single shock test cases and in comparison to two RM experiments including re-shock (Vetter-Sturtevant and Poggi, et.al.). Sensitivity to model parameters, to Atwood number, and to initial conditions are examined. Results here are in good agreement in some tests (HIT, RT) with the previous results reported for the mix model in the Lagrange calculations. The HIT turbulent decay agrees closely with analytic expectations, and the RT growth rate matches experimental values for the default values of the model coefficients proposed in [D-T]. Results for RM characterized with a power law growth rate differ from the previous mix model work but are still within the range for reasonable agreement with experiments. Sensitivity to IC values in the RM studies are examined; results are sensitive to initial values of L[t=O], which largely determines the RM mix layer growth rate, and generally differs from the IC values used in the RT studies. Result sensitivity to initial turbulence, K[t=O], is seen to be small but significant above a threshold value. Initial conditions can be adjusted so that single shock RM mix width results match experiments but we have not been able to obtain a good match for first shock and re-shock growth rates in the same experiment with a single set of parameters and Ie. Problematic issues with KH test problems are described. Resolution studies for an RM test problem show the K-L mix growth rate decreases as it converges at a supra-linear rate, and, convergence requires a fine grid (on the order of 10 microns). For comparison, a resolution study of a second mix model [Scannapieco and Cheng, Phys.Lett.A, 299(1),49, (2002)] acting on a two fluid interface problem was examined. The mix in this case was found to increase with grid resolution at low to moderate resolutions, but converged at comparably fine resolutions. In conclusion, these tests indicate that the Eulerian code K-L model, using the Dimonte Tipton default model closure coefficients, achieve reasonable results across many of the unit-physics experimental conditions. However, we were unable to obtain good matches simultaneously for shock and re-shock mix in a single experiment. Results are sensitive to initial conditions in the regimes under study, with different IC best suited to RT or RM mix. It is reasonable to expect IC sensitivity in extrapolating to high energy density regimes, or to experiments with deceleration due to arbitrary combinations of RT and RM. As a final comparison, the atomically generated mix fraction and the mix width were each compared for the K-L mix model and the Scannapieco model on an identical RM test problem. The Scannapieco mix fraction and width grow linearly. The K-L mix fraction and width grow with the same power law exponent, in contrast to expectations from analysis. In future work it is proposed to do more head-to-head comparisons between these two models and other mix model options on a full suite of physics test problems, such as interfacial deceleration due to pressure build-up during an idealized ICF implosion.

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

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Annual Cycle Integration of the NMC Medium-Range Forecasting (MRF) Model  

Science Conference Proceedings (OSTI)

The NMC Global Spectral Model was integrated for one year. The model used is the same as the 1989 operational medium range forecast model except that the horizontal resolution was reduced from T80 to T40. Overall, the model was very successful in ...

M. Kanamitsu; K. C. Mo; E. Kalnay

1990-12-01T23:59:59.000Z

202

Ocean Carbon Cycle Models from the Carbon Dioxide Information Analysis Center (CDIAC)  

DOE Data Explorer (OSTI)

•\tPacific data-model intercomparison from Patrick Wetzel (Max Planck Institute for Meteorology, Germany)

203

Investigation of the Sensitivity of Water Cycle Components Simulated by the Canadian Regional Climate Model to the Land Surface Parameterization, the Lateral Boundary Data, and the Internal Variability  

Science Conference Proceedings (OSTI)

This study investigates the sensitivity of components of the hydrological cycle simulated by the Canadian Regional Climate Model (CRCM) to lateral boundary forcing, the complexity of the land surface scheme (LSS), and the internal variability ...

Biljana Music; Daniel Caya

2009-02-01T23:59:59.000Z

204

Direct-contact condensers for open-cycle OTEC applications: Model validation with fresh water experiments for structured packings  

DOE Green Energy (OSTI)

The objective of the reported work was to develop analytical methods for evaluating the design and performance of advanced high-performance heat exchangers for use in open-cycle thermal energy conversion (OC-OTEC) systems. This report describes the progress made on validating a one-dimensional, steady-state analytical computer of fresh water experiments. The condenser model represents the state of the art in direct-contact heat exchange for condensation for OC-OTEC applications. This is expected to provide a basis for optimizing OC-OTEC plant configurations. Using the model, we examined two condenser geometries, a cocurrent and a countercurrent configuration. This report provides detailed validation results for important condenser parameters for cocurrent and countercurrent flows. Based on the comparisons and uncertainty overlap between the experimental data and predictions, the model is shown to predict critical condenser performance parameters with an uncertainty acceptable for general engineering design and performance evaluations. 33 refs., 69 figs., 38 tabs.

Bharathan, D.; Parsons, B.K.; Althof, J.A.

1988-10-01T23:59:59.000Z

205

A Unit Commitment Model with Demand Response for the Integration of Renewable Energies  

E-Print Network (OSTI)

The output of renewable energy fluctuates significantly depending on weather conditions. We develop a unit commitment model to analyze requirements of the forecast output and its error for renewable energies. Our model obtains the time series for the operational state of thermal power plants that would maximize the profits of an electric power utility by taking into account both the forecast of output its error for renewable energies and the demand response of consumers. We consider a power system consisting of thermal power plants, photovoltaic systems (PV), and wind farms and analyze the effect of the forecast error on the operation cost and reserves. We confirm that the operation cost was increases with the forecast error. The effect of a sudden decrease in wind power is also analyzed. More thermal power plants need to be operated to generate power to absorb this sudden decrease in wind power. The increase in the number of operating thermal power plants within a short period does not affect the total opera...

Ikeda, Yuichi; Kataoka, Kazuto; Ogimoto, Kazuhiko

2011-01-01T23:59:59.000Z

206

DESTRUCTIVE EXAMINATION OF 3-CYCLE LWR (LIGHT WATER REACTOR) FUEL RODS FROM TURKEY POINT UNIT 3 FOR THE CLIMAX - SPENT FUEL TEST  

DOE Green Energy (OSTI)

The destructive examination results of five light water reactor rods from the Turkey Point Unit 3 reactor are presented. The examinations included fission gas collection and analyses, burnup and hydrogen analyses, and a metallographic evaluation of the fuel, cladding, oxide, and hydrides. The rods exhibited a low fission gas release with all other results appearing representative for pressurized water reator fuel rods with similar burnups (28 GWd/MTU) and operating histories.

ATKIN SD

1981-06-01T23:59:59.000Z

207

Grid-BGC: A Grid-Enabled Terrestrial Carbon Cycle Modeling System, Euro-Par 2005  

E-Print Network (OSTI)

Abstract. Grid-BGC is a Grid-enabled terrestrial biogeochemical cycle simulator collaboratively developed by the National Center for Atmospheric Research (NCAR) and the University of Colorado (CU) with funding from NASA. The primary objective of the project is to utilize Globus Grid technology to integrate inexpensive commodity cluster computational resources at CU with the mass storage system at NCAR while hiding the logistics of data transfer and job submission from the scientists. We describe a typical process for simulating the terrestrial carbon cycle, present our solution architecture and software design, and describe our implementation experiences with Grid technology on our systems. By design the Grid-BGC software framework is extensible in that it can utilize other grid-accessible computational resources and can be readily applied to other climate simulation problems which have similar workflows. Overall, this project demonstrates an end-to-end system which leverages Grid technologies to harness distributed resources across organizational boundaries to achieve a cost-effective solution to a computeintensive problem. 1

Jason Cope; Craig Hartsough; Peter Thornton; Henry M. Tufo; Nathan Wilhelmi; Matthew Woitaszek

2005-01-01T23:59:59.000Z

208

Modeling and design of a reload PWR core for a 48-month fuel cycle  

Science Conference Proceedings (OSTI)

The objective of this research was to use state-of-the-art nuclear and fuel performance packages to evaluate the feasibility and costs of a 48 calendar month core in existing pressurized water reactor (PWR) designs, considering the full range of practical design and economic considerations. The driving force behind this research is the desire to make nuclear power more economically competitive with fossil fuel options by expanding the scope for achievement of higher capacity factors. Using CASMO/SIMULATE, a core design with fuel enriched to 7{sup w}/{sub o} U{sup 235} for a single batch loaded, 48-month fuel cycle has been developed. This core achieves an ultra-long cycle length without exceeding current fuel burnup limits. The design uses two different types of burnable poisons. Gadolinium in the form of gadolinium oxide (Gd{sub 2}O{sub 3}) mixed with the UO{sub 2} of selected pins is sued to hold down initial reactivity and to control flux peaking throughout the life of the core. A zirconium di-boride (ZrB{sub 2}) integral fuel burnable absorber (IFBA) coating on the Gd{sub 2}O{sub 3}-UO{sub 2} fuel pellets is added to reduce the critical soluble boron concentration in the reactor coolant to within acceptable limits. Fuel performance issues of concern to this design are also outlined and areas which will require further research are highlighted.

McMahon, M.V.; Driscoll, M.J.; Todreas, N.E. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

1997-05-01T23:59:59.000Z

209

Terrestrial carbon cycle - climate relations in eight CMIP5 earth system models  

Science Conference Proceedings (OSTI)

Eight Earth System Models from the Coupled Model Intercomparison Project (CMIP5) are evaluated, focusing on both the net carbon dioxide flux and its components, and their relation with climatic variables (temperature, precipitation and soil ...

Pu Shao; Xubin Zeng; Koichi Sakaguchi; Russell K. Monson; Xiaodong Zeng

210

Climate Model–Simulated Diurnal Cycles in HIRS Clear-Sky Brightness Temperatures  

Science Conference Proceedings (OSTI)

Clear-sky brightness temperature measurements from the High-Resolution Infrared Radiation Sounder (HIRS) are simulated with two climate models via a radiative transfer code. The models are sampled along the HIRS orbit paths to derive diurnal ...

Ian A. MacKenzie; Simon F. B. Tett; Anders V. Lindfors

2012-09-01T23:59:59.000Z

211

Completion Report for Model Evaluation Well ER-11-2: Corrective Action Unit 98: Frenchman Flat  

Science Conference Proceedings (OSTI)

Model Evaluation Well ER-11-2 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of Nevada Environmental Management Operations at the Nevada National Security Site (formerly known as the Nevada Test Site). The well was drilled in August 2012 as part of a model evaluation program in the Frenchman Flat area of Nye County, Nevada. The primary purpose of the well was to provide detailed geologic, hydrogeologic, chemical, and radionuclide data that can be used to test and build confidence in the applicability of the Frenchman Flat Corrective Action Unit flow and transport models for their intended purpose. In particular, this well was designed to provide data to evaluate the uncertainty in model forecasts of contaminant migration from the upgradient underground nuclear test PIN STRIPE, conducted in borehole U-11b in 1966. Well ER-11-2 will provide information that can be used to refine the Phase II Frenchman Flat hydrostratigraphic framework model if necessary, as well as to support future groundwater flow and transport modeling. The main 31.1-centimeter (cm) hole was drilled to a total depth of 399.6 meters (m). A completion casing string was not set in Well ER-11-2. However, a piezometer string was installed in the 31.1-cm open hole. The piezometer is composed of 7.3-cm stainless-steel tubing hung on 6.0-cm carbon-steel tubing via a crossover sub. The piezometer string was landed at 394.5 m, for monitoring the lower tuff confining unit. Data collected during and shortly after hole construction include composite drill cuttings samples collected every 3.0 m, various geophysical logs, water quality (including tritium and other test-related radionuclides) measurements, and water level measurements. The well penetrated 42.7 m of Quaternary and Tertiary alluvium and 356.9 m of Tertiary volcanic rock. The water-level measured in the piezometer string on September 25, 2012, was 353.8 m below ground surface. No tritium above levels detectable by field methods were encountered in this hole. No well development or hydrologic testing was conducted in this well immediately after completion, and future well development, sampling, and hydrologic testing planned for this well will be limited due to the diameter of the piezometer string. The stratigraphy, general lithology, and the water level are as expected, but the section of geology encountered is higher than expected due to faulting. No tritium above the minimum detection limit of the field equipment was detected because the target aquifer (the Topopah Spring aquifer) at Well ER-11-2 is structurally higher than expected and thus unsaturated.

NSTec Underground Test Area and Boreholes Programs and Operations

2013-01-22T23:59:59.000Z

212

Modeling the effects of late cycle oxygen enrichment on diesel engine combustion and emissions.  

DOE Green Energy (OSTI)

A multidimensional simulation of Auxiliary Gas Injection (AGI) for late cycle oxygen enrichment was exercised to assess the merits of AGI for reducing the emissions of soot from heavy duty diesel engines while not adversely affecting the NO{sub x} emissions of the engine. Here, AGI is the controlled enhancement of mixing within the diesel engine combustion chamber by high speed jets of air or another gas. The engine simulated was a Caterpillar 3401 engine. For a particular operating condition of this engine, the simulated soot emissions of the engine were reduced by 80% while not significantly affecting the engine-out NO{sub x} emissions compared to the engine operating without AGI. The effects of AGI duration, timing, and orientation are studied to confirm the window of opportunity for realizing lower engine-out soot while not increasing engine out NO{sub x} through controlled enhancement of in-cylinder mixing. These studies have shown that this window occurs during the late combustion cycle, from 20 to 60 crank angle degrees after top-dead-center. During this time, the combustion chamber temperatures are sufficiently high that soot oxidation increases in response in increased mixing, but the temperature is low enough that NO{sub x} reactions are quenched. The effect of the oxygen composition of the injected air is studied for the range of compositions between 21% and 30% oxygen by volume. This is the range of oxygen enrichment that is practical to produce from an air separation membrane. Simulations showed that this level of oxygen enrichment is insufficient to provide an additional benefit by either increasing the level of soot oxidation or prolonging the window of opportunity for increasing soot oxidation through enhanced mixing.

Mather, D. K.; Foster, D. E.; Poola, R. B.; Longman, D. E.; Chanda, A.; Vachon, T. J.

2002-02-28T23:59:59.000Z

213

Hydrological Cycle in the Danube basin in present-day and XXII century simulations by IPCCAR4 global climate models  

E-Print Network (OSTI)

We present an intercomparison and verification analysis of 20 GCMs included in the 4th IPCC assessment report regarding their representation of the hydrological cycle on the Danube river basin for 1961-2000 and for the 2161-2200 SRESA1B scenario runs. The basin-scale properties of the hydrological cycle are computed by spatially integrating the precipitation, evaporation, and runoff fields using the Voronoi-Thiessen tessellation formalism. The span of the model simulated mean annual water balances is of the same order of magnitude of the observed Danube discharge of the Delta; the true value is within the range simulated by the models. Some land components seem to have deficiencies since there are cases of violation of water conservation when annual means are considered. The overall performance and the degree of agreement of the GCMs are comparable to those of the RCMs analyzed in a previous work, in spite of the much higher resolution and common nesting of the RCMs. The reanalyses are shown to feature severa...

Lucarini, Valerio; Kriegerova, Ida; Speranza, Antonio; 10.1029/2007JD009167

2011-01-01T23:59:59.000Z

214

MELCOR Model of the Spent Fuel Pool of Fukushima Dai-ichi Unit 4  

DOE Green Energy (OSTI)

Unit 4 of the Fukushima Dai-ichi Nuclear Power Plant suffered a hydrogen explosion at 6:00 am on March 15, 2011, exactly 3.64 days after the earthquake hit the plant and the off-site power was lost. The earthquake occurred on March 11 at 2:47 pm. Since the reactor of this Unit 4 was defueled on November 29, 2010, and all its fuel was stored in the spent fuel pool (SFP4), it was first believed that the explosion was caused by hydrogen generated by the spent fuel, in particular, by the recently discharged core. The hypothetical scenario was: power was lost, cooling to the SFP4 water was lost, pool water heated/boiled, water level decreased, fuel was uncovered, hot Zircaloy reacted with steam, hydrogen was generated and accumulated above the pool, and the explosion occurred. Recent analyses of the radioisotopes present in the water of the SFP4 and underwater video indicated that this scenario did not occur - the fuel in this pool was not damaged and was never uncovered the hydrogen of the explosion was apparently generated in Unit 3 and transported through exhaust ducts that shared the same chimney with Unit 4. This paper will try to answer the following questions: Could that hypothetical scenario in the SFP4 had occurred? Could the spent fuel in the SPF4 generate enough hydrogen to produce the explosion that occurred 3.64 days after the earthquake? Given the magnitude of the explosion, it was estimated that at least 150 kg of hydrogen had to be generated. As part of the investigations of this accident, MELCOR models of the SFP4 were prepared and a series of calculations were completed. The latest version of MELCOR, version 2.1 (Ref. 1), was employed in these calculations. The spent fuel pool option for BWR fuel was selected in MELCOR. The MELCOR model of the SFP4 consists of a total of 1535 fuel assemblies out of which 548 assemblies are from the core defueled on Nov. 29, 2010, 783 assemblies are older assemblies, and 204 are new/fresh assemblies. The total decay heat of the fuel in the pool was, at the time of the accident, 2.284 MWt, of which 1.872 MWt were from the 548 assemblies of the last core discharged and 0.412 MWt were from the older 783 assemblies. These decay heat values were calculated at Oak Ridge National Laboratory using the ORIGEN2.2 code (Ref. 2) - they agree with values reported elsewhere (Ref. 3). The pool dimensions are 9.9 m x 12.2 m x 11.8 m (height), and with the water level at 11.5 m, the pool volume is 1389 m3, of which only 1240 m3 is water, as some volume is taken by the fuel and by the fuel racks. The initial water temperature of the SFP4 was assumed to be 301 K. The fuel racks are made of an aluminum alloy but are modeled in MELCOR with stainless steel and B4C. MELCOR calculations were completed for different initial water levels: 11.5 m (pool almost full, water is only 0.3 m below the top rim), 4.4577 m (top of the racks), 4.2 m, and 4.026 m (top of the active fuel). A calculation was also completed for a rapid loss of water due to a leak at the bottom of the pool, with the fuel rapidly uncovered and oxidized in air. Results of these calculations are shown in the enclosed Table I. The calculation with the initial water level at 11.5 m (full pool) takes 11 days for the water to boil down to the top of the fuel racks, 11.5 days for the fuel to be uncovered, 14.65 days to generate 150 kg of hydrogen and 19 days for the pool to be completely dry. The calculation with the initial water level at 4.4577 m, takes 1.1 days to uncover the fuel and 4.17 days to generate 150 kg of hydrogen. The calculation with the initial water level at 4.02 m takes 3.63 days to generate 150 kg of hydrogen this is exactly the time when the actual explosion occurred in Unit 4. Finally, fuel oxidation in air after the pool drained the water in 20 minutes, generates only 10 kg of hydrogen this is because very little steam is available and Zircaloy (Zr) oxidation with the oxygen of the air does not generate hydrogen. MELCOR calculated water levels and hydrogen generated in the SFP4 as a function of time for initial water le

Carbajo, Juan J [ORNL

2012-01-01T23:59:59.000Z

215

Life-cycle assessment of municipal solid wastes: Development of the WASTED model  

Science Conference Proceedings (OSTI)

This paper describes the development of the Waste Analysis Software Tool for Environmental Decisions (WASTED) model. This model provides a comprehensive view of the environmental impacts of municipal solid waste management systems. The model consists of a number of separate submodels that describe a typical waste management process: waste collection, material recovery, composting, energy recovery from waste and landfilling. These submodels are combined to represent a complete waste management system. WASTED uses compensatory systems to account for the avoided environmental impacts derived from energy recovery and material recycling. The model is designed to provide solid waste decision-makers and environmental researchers with a tool to evaluate waste management plans and to improve the environmental performance of solid waste management strategies. The model is user-friendly and compares favourably with other earlier models.

Diaz, R. [Civil Engineering Department, Ryerson University, 350 Victoria Street, Toronto, Ont., M5B 2K3 (Canada); Warith, M. [Civil Engineering Department, Ryerson University, 350 Victoria Street, Toronto, Ont., M5B 2K3 (Canada)]. E-mail: mwarith@ryerson.ca

2006-07-01T23:59:59.000Z

216

Modeling the effects of groundwater-fed irrigation on terrestrial hydrology over the conterminous United States  

Science Conference Proceedings (OSTI)

Human alteration of the land surface hydrologic cycle is substantial. Recent studies suggest that local water management practices including groundwater pumping and irrigation could significantly alter the quantity and distribution of water in the ...

Guoyong Leng; Maoyi Huang; Qiuhong Tang; Huilin Gao; L. Ruby Leung

217

An adaptive modeling and simulation environment for combined-cycle data reconciliation and degradation estimation.  

E-Print Network (OSTI)

??Performance engineers face the major challenge in modeling and simulation for the after-market power system due to system degradation and measurement errors. Currently, the majority… (more)

Lin, TsungPo

2008-01-01T23:59:59.000Z

218

Stable Atmospheric Boundary Layers and Diurnal Cycles: Challenges for Weather and Climate Models  

Science Conference Proceedings (OSTI)

The representation of the atmospheric boundary layer is an important part of weather and climate models and impacts many applications such as air quality and wind energy. Over the years, the performance in modeling 2-m temperature and 10-m wind speed has ...

A. A. M. Holtslag; G. Svensson; P. Baas; S. Basu; B. Beare; A. C. M. Beljaars; F. C. Bosveld; J. Cuxart; J. Lindvall; G. J. Steeneveld; M. Tjernström; B. J. H. Van De Wiel

2013-11-01T23:59:59.000Z

219

Sensitivity Experiments with a Model of the Ice Age Cycle: The Response to Milankovitch Forcing  

Science Conference Proceedings (OSTI)

We address the question of the extent to which a simple one-dimensional time-dependent climate model is able to explain the fluctuations of continental ice volume which have occurred during the last quarter of the Pleistocene epoch. The model ...

W. T. Hyde; W. R. Peltier

1987-05-01T23:59:59.000Z

220

Completion Report for Model Evaluation Well ER-5-5: Corrective Action Unit 98: Frenchman Flat  

Science Conference Proceedings (OSTI)

Model Evaluation Well ER-5-5 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of Nevada Environmental Management Operations at the Nevada National Security Site (formerly known as the Nevada Test Site). The well was drilled in July and August 2012 as part of a model evaluation well program in the Frenchman Flat area of Nye County, Nevada. The primary purpose of the well was to provide detailed geologic, hydrogeologic, chemical, and radiological data that can be used to test and build confidence in the applicability of the Frenchman Flat Corrective Action Unit flow and transport models for their intended purpose. In particular, this well was designed to obtain data to evaluate the uncertainty in model forecasts of contaminant migration from the upgradient underground nuclear test MILK SHAKE, conducted in Emplacement Hole U-5k in 1968, which were considered to be uncertain due to the unknown extent of a basalt lava-flow aquifer present in this area. Well ER-5-5 is expected to provide information to refine the Phase II Frenchman Flat hydrostratigraphic framework model, if necessary, as well as to support future groundwater flow and transport modeling. The 31.1-centimeter (cm) diameter hole was drilled to a total depth of 331.3 meters (m). The completion string, set at the depth of 317.2 m, consists of 16.8-cm stainless-steel casing hanging from 19.4-cm carbon-steel casing. The 16.8-cm stainless-steel casing has one slotted interval open to the basalt lava-flow aquifer and limited intervals of the overlying and underlying alluvial aquifer. A piezometer string was also installed in the annulus between the completion string and the borehole wall. The piezometer is composed of 7.3-cm stainless-steel tubing suspended from 6.0-cm carbon-steel tubing. The piezometer string was landed at 319.2 m, to monitor the basalt lava-flow aquifer. Data collected during and shortly after hole construction include composite drill cuttings samples collected every 3.0 m, various geophysical logs, preliminary water quality measurements, and water-level measurements. The well penetrated 331.3 m of Quaternary–Tertiary alluvium, including an intercalated layer of saturated basalt lava rubble. No well development or hydrologic testing was conducted in this well immediately after completion; however, a preliminary water level was measured in the piezometer string at the depth of 283.4 m on September 25, 2012. No tritium above the minimum detection limit of the field instruments was detected in this hole. Future well development, sampling, and hydrologic testing planned for this well will provide more accurate hydrologic information for this site. The stratigraphy, general lithology, and water level were as expected, though the expected basalt lava-flow aquifer is basalt rubble and not the dense, fractured lava as modeled. The lack of tritium transport is likely due to the difference in hydraulic properties of the basalt lava-flow rubble encountered in the well, compared to those of the fractured aquifer used in the flow and transport models.

NSTec Underground Test Area and Boreholes Programs and Operations

2013-01-18T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Use of a dynamic simulation model to understand nitrogen cycling in the middle Rio Grande, NM.  

Science Conference Proceedings (OSTI)

Water quality often limits the potential uses of scarce water resources in semiarid and arid regions. To best manage water quality one must understand the sources and sinks of both solutes and water to the river system. Nutrient concentration patterns can identify source and sink locations, but cannot always determine biotic processes that affect nutrient concentrations. Modeling tools can provide insight into these large-scale processes. To address questions about large-scale nitrogen removal in the Middle Rio Grande, NM, we created a system dynamics nitrate model using an existing integrated surface water--groundwater model of the region to evaluate our conceptual models of uptake and denitrification as potential nitrate removal mechanisms. We modeled denitrification in groundwater as a first-order process dependent only on concentration and used a 5% denitrification rate. Uptake was assumed to be proportional to transpiration and was modeled as a percentage of the evapotranspiration calculated within the model multiplied by the nitrate concentration in the water being transpired. We modeled riparian uptake as 90% and agricultural uptake as 50% of the respective evapotranspiration rates. Using these removal rates, our model results suggest that riparian uptake, agricultural uptake and denitrification in groundwater are all needed to produce the observed nitrate concentrations in the groundwater, conveyance channels, and river as well as the seasonal concentration patterns. The model results indicate that a total of 497 metric tons of nitrate-N are removed from the Middle Rio Grande annually. Where river nitrate concentrations are low and there are no large nitrate sources, nitrate behaves nearly conservatively and riparian and agricultural uptake are the most important removal mechanisms. Downstream of a large wastewater nitrate source, denitrification and agricultural uptake were responsible for approximately 90% of the nitrogen removal.

Meixner, Tom (University of Arizona, Tucson, AZ); Tidwell, Vincent Carroll; Oelsner, Gretchen (University of Arizona, Tucson, AZ); Brooks, Paul (University of Arizona, Tucson, AZ); Roach, Jesse D.

2008-08-01T23:59:59.000Z

222

Update 1 to: A Dispersion Modeling Analysis of Downwash from...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant, Modeling Unit 1 Emissions in a Cycling Mode Update 1 to: A Dispersion Modeling Analysis of...

223

Influence of climate model biases and daily-scale temperature and precipitation events on hydrological impacts assessment: A case study of the United States  

Science Conference Proceedings (OSTI)

The Intergovernmental Panel on Climate Change's Fourth Assessment Report concludes that climate change is now unequivocal, and associated increases in evaporation and atmospheric water content could intensify the hydrological cycle. However, the biases and coarse spatial resolution of global climate models limit their usefulness in hydrological impact assessment. In order to reduce these limitations, we use a high-resolution regional climate model (RegCM3) to drive a hydrological model (variable infiltration capacity) for the full contiguous United States. The simulations cover 1961-1990 in the historic period and 2071-2100 in the future (A2) period. A quantile-based bias correction technique is applied to the times series of RegCM3-simulated precipitation and temperature. Our results show that biases in the RegCM3 fields not only affect the magnitude of hydrometeorological variables in the baseline hydrological simulation, but they also affect the response of hydrological variables to projected future anthropogenic increases in greenhouse forcing. Further, we find that changes in the intensity and occurrence of severe wet and hot events are critical in determining the sign of hydrologic change. These results have important implications for the assessment of potential future hydrologic changes, as well as for developing approaches for quantitative impacts assessment.

Ashfaq, Moetasim [ORNL; Bowling, Laura C. [Purdue University; Cherkauer, Keith [Purdue University; Pal, Jeremy [Loyola University; Diffenbaugh, Noah [Stanford University

2010-01-01T23:59:59.000Z

224

Modeling and optimization of a modified claus process as part of an integrted gasification combined cycle (IGCC) power plant with CO2 capture  

DOE Green Energy (OSTI)

The modified Claus process is one of the most common technologies for sulfur recovery from acid gas streams. Important design criteria for the Claus unit, when part of an Integrated Gasification Combined Cycle (IGCC) power plant, are the ability to destroy ammonia completely and recover sulfur thoroughly from a relatively low purity acid gas stream without sacrificing flame stability. Due to these criteria, modifications are often required to the conventional process, resulting in a modified Claus process. For the studies discussed here, these modifications include the use of a 95% pure oxygen stream as the oxidant, a split flow configuration, and the preheating of the feeds with the intermediate pressure steam generated in the waste heat boiler (WHB). In the future, for IGCC plants with CO2 capture, the Claus unit must satisfy emission standards without sacrificing the plant efficiency in the face of typical disturbances of an IGCC plant such as rapid change in the feed flowrates due to load-following and wide changes in the feed composition because of changes in the coal feed to the gasifier. The Claus unit should be adequately designed and efficiently operated to satisfy these objectives. Even though the Claus process has been commercialized for decades, most papers concerned with the modeling of the Claus process treat the key reactions as equilibrium reactions. Such models are validated by manipulating the temperature approach to equilibrium for a set of steady-state operating data, but are of limited use for dynamic studies. One of the objectives of this study is to develop a model that can be used for dynamic studies. In a Claus process, especially in the furnace and the WHB, many reactions may take place. In this work, a set of linearly independent reactions has been identified and kinetic models of the furnace flame and anoxic zones, WHB, and catalytic reactors have been developed. To facilitate the modeling of the Claus furnace, a four-stage method was devised so as to determine which set of linearly independent reactions would best describe the product distributions from available plant data. Various approaches are taken to derive the kinetic rate expressions which are either missing in the open literature or found to be inconsistent. A set of plant data is used for optimal estimation of the kinetic parameters. The final model agrees well with the published plant data. Using the developed kinetics models of the Claus reaction furnace, WHB, and catalytic stages, two optimization studies are carried out. The first study shows that there exists an optimal steam pressure generated in the WHB that balances hydrogen yield, oxygen demand, and power generation. In the second study, it is shown that an optimal H2S/SO2 ratio exists that balances single-pass conversion, hydrogen yield, oxygen demand, and power generation. In addition, an operability study has been carried out to examine the operating envelope in which both H2S/SO2 ratio and adiabatic flame temperature can be controlled in the face of disturbances typical for the operation of an IGCC power plant with CO2 capture. Impact of CO2 capture on the Claus process has also been discussed.

Jones, D.; Bhattacharyya, D.; Turton, R.; Zitney, S.

2011-01-01T23:59:59.000Z

225

Markov decision models for the optimal maintenance of a production unit with an upstream buffer  

Science Conference Proceedings (OSTI)

We consider a manufacturing system in which a buffer has been placed between the input generator and the production unit. The input generator supplies at a constant rate the buffer with the raw material, which is pulled by the production unit. The pull-rate ... Keywords: Control-limit policies, Dynamic programming, Maintenance, Production, Upstream buffer

A. Pavitsos; E. G. Kyriakidis

2009-06-01T23:59:59.000Z

226

A Stochastic Unit Commitment Model for a Local Hans F. Ravn, Jannik Riisom, and Camilla Schaumburg-Mller  

E-Print Network (OSTI)

of local combined heat and power (CHP) plants has been characterised by large growth throughout a significant growth of wind power, particularly in the Western Danish system. As both the power produced1 A Stochastic Unit Commitment Model for a Local CHP Plant Hans F. Ravn, Jannik Riisom, and Camilla

227

The United States of America and the People`s Republic of China experts report on integrated gasification combined-cycle technology (IGCC)  

SciTech Connect

A report written by the leading US and Chinese experts in Integrated Gasification Combined Cycle (IGCC) power plants, intended for high level decision makers, may greatly accelerate the development of an IGCC demonstration project in the People`s Republic of China (PRC). The potential market for IGCC systems in China and the competitiveness of IGCC technology with other clean coal options for China have been analyzed in the report. Such information will be useful not only to the Chinese government but also to US vendors and companies. The goal of this report is to analyze the energy supply structure of China, China`s energy and environmental protection demand, and the potential market in China in order to make a justified and reasonable assessment on feasibility of the transfer of US Clean Coal Technologies to China. The Expert Report was developed and written by the joint US/PRC IGCC experts and will be presented to the State Planning Commission (SPC) by the President of the CAS to ensure consideration of the importance of IGCC for future PRC power production.

1996-12-01T23:59:59.000Z

228

Long-Term Climate Commitments Projected with Climate–Carbon Cycle Models  

Science Conference Proceedings (OSTI)

Eight earth system models of intermediate complexity (EMICs) are used to project climate change commitments for the recent Intergovernmental Panel on Climate Change’s (IPCC’s) Fourth Assessment Report (AR4). Simulations are run until the year ...

G.-K. Plattner; R. Knutti; F. Joos; T. F. Stocker; W. von Bloh; V. Brovkin; D. Cameron; E. Driesschaert; S. Dutkiewicz; M. Eby; N. R. Edwards; T. Fichefet; J. C. Hargreaves; C. D. Jones; M. F. Loutre; H. D. Matthews; A. Mouchet; S. A. Müller; S. Nawrath; A. Price; A. Sokolov; K. M. Strassmann; A. J. Weaver

2008-06-01T23:59:59.000Z

229

Near-N Oscillations and Deep-Cycle Turbulence in an Upper-Equatorial Undercurrent Model  

Science Conference Proceedings (OSTI)

Direct numerical simulation (DNS) is used to investigate the role of shear instabilities in turbulent mixing in a model of the upper Equatorial Undercurrent (EUC). The background flow consists of a westward-moving surface mixed layer above a ...

Hieu T. Pham; Sutanu Sarkar; Kraig B. Winters

2012-12-01T23:59:59.000Z

230

A Transient Model of Induced Natural Circulation Thermal Cycling for Hydrogen Isotope Separation  

SciTech Connect

The property of selective temperature dependence of adsorption and desorption of hydrogen isotopes by palladium is used for isotope separation. A proposal to use natural circulation of nitrogen to alternately heat and cool a packed bed of palladium coated beads is under active investigation, and a device consisting of two interlocking natural convection loops is being designed. A transient numerical model of the device has been developed to aid the design process. It is a one-dimensional finite-difference model, using the Boussinesq approximation. The thermal inertia of the pipe walls and other heat structures as well as the heater control logic is included in the model. Two system configurations were modeled and results are compared.

SHADDAY, MARTIN

2005-07-12T23:59:59.000Z

231

Program on Technology Innovation: Development of an Integrated Gasification Combined Cycle Performance and Cost Modeling Tool  

Science Conference Proceedings (OSTI)

This report describes the development of an integrated performance and cost model for advanced coal power plant undertaken to enable users to screen technologies prior to engaging in more extensive studies of their preferred choice. Such screening activities generally require utilities to contract with outside engineering firms with access to sophisticated engineering modeling software and experienced staff to perform the studies, thus costing significant time and investment.

2010-12-31T23:59:59.000Z

232

Development and use of the GREET model to estimate fuel-cycle energy use and emissions of various transportation technologies and fuels  

SciTech Connect

This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel- cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, sulfur oxides, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied petroleum gas, methanol, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydrogen, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; and landfill gases to methanol. This report presents fuel-cycle energy use and emissions for a 2000 model-year car powered by each of the fuels that are produced from the primary energy sources considered in the study.

Wang, M.Q.

1996-03-01T23:59:59.000Z

233

Simulated effects of elevated CO{sub 2} on nitrogen cycling using the NuCM model  

DOE Green Energy (OSTI)

The interactions between elevated CO{sub 2} and N cycling were explored using simulations generated by the Nutrient Cycling Model (NuCM) for a Pinus taeda site at Duke, North Carolina and a mixed deciduous site at Walker Branch, Tennessee. The simulations tested whether N limitation would prevent growth increase in response to elevated CO{sub 2} and whether growth response to CO{sub 2} in N-limited systems could be facilitated by increased biomass/N (reduced concentration) and/or increased litter N mineralization. Nitrogen limitation precluded additional growth when target growth rates and litterfall were increased (simulating potential response to elevated CO{sub 2}) at the Duke site. At the Walker Branch site, increasing target growth and litterfall caused a slight (790) increases in growth. Reducing foliar N concentrations caused reduced growth because of N limitation created by reduced litter quality (C/N ratio), reduced decomposition and N accumulation in forest floor. These effects were most pronounced at the Duke site, where the forest floor N turnover rate was lower than at the Walker Branch site. Reducing wood N concentration allowed prolonged increases in growth because of greater biomass/N; however, N uptake was reduced, allowing greater N immobilization in the forest floor and soil. Increased N mineralization caused increased growth at the Duke site but not at Walker Branch.

D.W. Johnson

1998-10-14T23:59:59.000Z

234

Controls on Fluxes of Mercury in Aquatic Food Webs: Application of the Dynamic Mercury Cycling Model to Four Enclosure Experiments w ith Additions of Stable Mercury Isotopes  

Science Conference Proceedings (OSTI)

New controls on utility mercury emissions are under consideration in order to limit human exposure to mercury resulting from fish consumption. Evaluation of such measures requires an understanding of how mercury cycles through lakes and streams. This report describes the application of EPRI's Dynamic Mercury Cycling Model (D-MCM) to experiments involving the addition of stable mercury Hg(II) isotopes to four 10-meter-diameter enclosures in a lake.

2001-09-21T23:59:59.000Z

235

Nuclear Fuel Cycle and Waste Management Technologies - Nuclear Engineering  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Fuel Cycle and Nuclear Fuel Cycle and Waste Management Technologies Nuclear Fuel Cycle and Waste Management Technologies Overview Modeling and analysis Unit Process Modeling Mass Tracking System Software Waste Form Performance Modeling Safety Analysis, Hazard and Risk Evaluations Development, Design, Operation Overview Systems and Components Development Expertise System Engineering Design Other Major Programs Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE Division on Flickr Nuclear Fuel Cycle and Waste Management Technologies Overview Bookmark and Share Much of the NE Division's research is directed toward developing software and performing analyses, system engineering design, and experiments to support the demonstration and optimization of the electrometallurgical

236

On the Influence of the Unit Cell Type on the Wave Function in One-Dimensional Kronig-Penney Models  

E-Print Network (OSTI)

We study the influence of the different choice of unit cells on the Bloch solutions of Schr\\c{c}dinger equation for one-dimensional periodic Kronig- Penney models with rectangular potential barriers or potential wells and partially constant effectiv mass. We obtain generalized Kronig-Penney relations for bulk states and exact expressions for the corresponding periodic parts of the Bloch wave functions for the two possible choices of the matching conditions in an unit cell. We show also that our analitic expressions reduce to the well known expressions for the Kronig-Penney relations and Bloch waves under constant effective mass and appropriate matching conditions.

Tashkova, M G; Donev, S G

2002-01-01T23:59:59.000Z

237

On the Influence of the Unit Cell Type on the Wave Function in One-Dimensional Kronig-Penney Models  

E-Print Network (OSTI)

We study the influence of the different choice of unit cells on the Bloch solutions of Schr\\c{c}dinger equation for one-dimensional periodic Kronig- Penney models with rectangular potential barriers or potential wells and partially constant effectiv mass. We obtain generalized Kronig-Penney relations for bulk states and exact expressions for the corresponding periodic parts of the Bloch wave functions for the two possible choices of the matching conditions in an unit cell. We show also that our analitic expressions reduce to the well known expressions for the Kronig-Penney relations and Bloch waves under constant effective mass and appropriate matching conditions.

M. G. Tashkova; A. M. Miteva; S. G. Donev

2002-04-10T23:59:59.000Z

238

Life cycle model for evaluating the sustainability of concrete infrastructure systems  

E-Print Network (OSTI)

by the Department of Energy (USDOE 2004). A 4% discount rate was used for all construction activities. In addition. Carbon dioxide emissions from the global cement industry. Annual Reviews of Energy and the Envi- ronment. The model is applied to two alternative concrete bridge deck designs: one a conventional steel re- inforced

Lepech, Michael D.

239

Annual Cycle of Poleward Heat Transport in the Ocean: Results from High-Resolution Modeling of the North and Equatorial Atlantic  

Science Conference Proceedings (OSTI)

The annual cycle of meridional heat transport in the North and equatorial Atlantic Ocean is studied by means of the high-resolution numerical model that had been developed in recent years as a Community Modeling Effort for the World Ocean ...

Claus W. Böning; Peter Herrmann

1994-01-01T23:59:59.000Z

240

Dynamic-Model-Based Seasonal Prediction of Meteorological Drought over the Contiguous United States  

Science Conference Proceedings (OSTI)

A simple method was developed to forecast 3- and 6-month standardized precipitation indices (SPIs) for the prediction of meteorological drought over the contiguous United States based on precipitation seasonal forecasts from the NCEP Climate ...

Jin-Ho Yoon; Kingtse Mo; Eric F. Wood

2012-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Modeling Water Withdrawal and Consumption for Electricity Generation in the United States  

E-Print Network (OSTI)

Water withdrawals for thermoelectric cooling account for a significant portion of total water use in the United States. Any change in electrical energy generation policy and technologies has the potential to have a major ...

Strzepek, Kenneth M.

2012-06-15T23:59:59.000Z

242

Determining the Sources of Regional Haze in the Southeastern United States Using the CMAQ Model  

Science Conference Proceedings (OSTI)

A detailed sensitivity analysis was conducted to help to quantify the impacts of various emission control options in terms of potential visibility improvements at class I national parks and wilderness areas in the southeastern United States. ...

M. Talat Odman; Yongtao Hu; Alper Unal; Armistead G. Russell; James W. Boylan

2007-11-01T23:59:59.000Z

243

Associative list processing unit  

SciTech Connect

An associative list processing unit and method comprising employing a plurality of prioritized cell blocks and permitting inserts to occur in a single clock cycle if all of the cell blocks are not full. Also, an associative list processing unit and method comprising employing a plurality of prioritized cell blocks and using a tree of prioritized multiplexers descending from the plurality of cell blocks.

Hemmert, Karl Scott; Underwood, Keith D.

2013-01-29T23:59:59.000Z

244

Combined effects of short-term rainfall patterns and soil texture on nitrogen cycling -- A Modeling Analysis  

Science Conference Proceedings (OSTI)

Precipitation variability and magnitude are expected to change in many parts of the world over the 21st century. We examined the potential effects of intra-annual rainfall patterns on soil nitrogen (N) transport and transformation in the unsaturated soil zone using a deterministic dynamic modeling approach. The model (TOUGHREACT-N), which has been tested and applied in several experimental and observational systems, mechanistically accounts for microbial activity, soil-moisture dynamics that respond to precipitation variability, and gaseous and aqueous tracer transport in the soil. Here, we further tested and calibrated the model against data from a precipitation variability experiment in a tropical system in Costa Rica. The model was then used to simulate responses of soil moisture, microbial dynamics, nitrogen (N) aqueous and gaseous species, N leaching, and N trace-gas emissions to changes in rainfall patterns; the effect of soil texture was also examined. The temporal variability of nitrate leaching and NO, N{sub 2}, and N{sub 2}O effluxes were significantly influenced by rainfall dynamics. Soil texture combined with rainfall dynamics altered soil moisture dynamics, and consequently regulated soil N responses to precipitation changes. The clay loam soil more effectively buffered water stress during relatively long intervals between precipitation events, particularly after a large rainfall event. Subsequent soil N aqueous and gaseous losses showed either increases or decreases in response to increasing precipitation variability due to complex soil moisture dynamics. For a high rainfall scenario, high precipitation variability resulted in as high as 2.4-, 2.4-, 1.2-, and 13-fold increases in NH{sub 3}, NO, N{sub 2}O and NO{sub 3}{sup -} fluxes, respectively, in clay loam soil. In sandy loam soil, however, NO and N{sub 2}O fluxes decreased by 15% and 28%, respectively, in response to high precipitation variability. Our results demonstrate that soil N cycling responses to increasing precipitation variability depends on precipitation amount and soil texture, and that accurate prediction of future N cycling and gas effluxes requires models with relatively sophisticated representation of the relevant processes.

Gu, C.; Riley, W.J.

2009-11-01T23:59:59.000Z

245

Long-Term Climate Modeling and Hydrological Response to Climate Cycles in the Yucca Mountain Region  

Science Conference Proceedings (OSTI)

Climate and its influence on hydrological conditions are important considerations in the evaluation of the Yucca Mountain (YM) site as a geologic repository for disposal of U.S. commercial spent nuclear fuel and defense high level radioactive wastes. This report updates previous EPRI studies (reports 1013445 and 1015045), which produced a quantitative and paleo-climate-calibrated/verified model of how climate, infiltration, and YM flow properties might appear in the future. The studies also supported ass...

2009-06-30T23:59:59.000Z

246

Financing Strategies for Nuclear Fuel Cycle Facility  

SciTech Connect

To help meet our nation’s energy needs, reprocessing of spent nuclear fuel is being considered more and more as a necessary step in a future nuclear fuel cycle, but incorporating this step into the fuel cycle will require considerable investment. This report presents an evaluation of financing scenarios for reprocessing facilities integrated into the nuclear fuel cycle. A range of options, from fully government owned to fully private owned, was evaluated using a DPL (Dynamic Programming Language) 6.0 model, which can systematically optimize outcomes based on user-defined criteria (e.g., lowest life-cycle cost, lowest unit cost). Though all business decisions follow similar logic with regard to financing, reprocessing facilities are an exception due to the range of financing options available. The evaluation concludes that lowest unit costs and lifetime costs follow a fully government-owned financing strategy, due to government forgiveness of debt as sunk costs. Other financing arrangements, however, including regulated utility ownership and a hybrid ownership scheme, led to acceptable costs, below the Nuclear Energy Agency published estimates. Overwhelmingly, uncertainty in annual capacity led to the greatest fluctuations in unit costs necessary for recovery of operating and capital expenditures; the ability to determine annual capacity will be a driving factor in setting unit costs. For private ventures, the costs of capital, especially equity interest rates, dominate the balance sheet; the annual operating costs dominate the government case. It is concluded that to finance the construction and operation of such a facility without government ownership could be feasible with measures taken to mitigate risk, and that factors besides unit costs should be considered (e.g., legal issues, social effects, proliferation concerns) before making a decision on financing strategy.

David Shropshire; Sharon Chandler

2005-12-01T23:59:59.000Z

247

Prevention of Compressor Short Cycling in Direct-Expansion (DX...  

NLE Websites -- All DOE Office Websites (Extended Search)

Units, Part 1: Theoretical Analysis and Simulation Title Prevention of Compressor Short Cycling in Direct-Expansion (DX) Rooftop Units, Part 1: Theoretical Analysis and Simulation...

248

Prevention of Compressor Short Cycling in Direct-Expansion (DX...  

NLE Websites -- All DOE Office Websites (Extended Search)

Units- Part 2: Field Investigation Title Prevention of Compressor Short Cycling in Direct-Expansion (DX) Rooftop Units- Part 2: Field Investigation Publication Type Journal Article...

249

Building Life-Cycle Cost (BLCC) Program | Open Energy Information  

Open Energy Info (EERE)

Building Life-Cycle Cost (BLCC) Program Building Life-Cycle Cost (BLCC) Program Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Building Life-Cycle Cost (BLCC) Program Agency/Company /Organization: United States Department of Energy Partner: National Institute of Standards and Technology Sector: Energy Focus Area: Buildings, Energy Efficiency Phase: Create a Vision, Determine Baseline, Evaluate Options, Develop Goals, Prepare a Plan Topics: Finance, Pathways analysis Resource Type: Software/modeling tools User Interface: Desktop Application Website: www1.eere.energy.gov/femp/information/download_blcc.html Cost: Free OpenEI Keyword(s): EERE tool, Building Life-Cycle Cost, BLCC References: Building Life-Cycle Cost (BLCC) Programs[1] Building Energy Software Tools Directory: BLCC[2]

250

Economic Consequences of Alternative Solution Methods for Centralized Unit Commitment in Day-Ahead Electricity Markets  

E-Print Network (OSTI)

Short-term scheduling of combined cycle units,” IEEE Trans.complex units such as combined-cycle com- bustion turbines (

Sioshansi, Ramteen; O'Neill, Richard; Oren, Shmuel S

2008-01-01T23:59:59.000Z

251

Dynamics and control modeling of the closed-cycle gas turbine (GT-HTGR) power plant  

SciTech Connect

The simulation if presented for the 800-MW(e) two-loop GT-HTGR plant design with the REALY2 transient analysis computer code, and the modeling of control strategies called for by the inherently unique operational requirements of a multiple loop GT-HTGR is described. Plant control of the GT-HTGR is constrained by the nature of its power conversion loops (PCLs) in which the core cooling flow and the turbine flow are directly related and thus changes in flow affect core cooling as well as turbine power. Additionally, the high thermal inertia of the reactor core precludes rapid changes in the temperature of the turbine inlet flow.

Bardia, A.

1980-02-01T23:59:59.000Z

252

Application of linear multiple model predictive control (MMPC) framework towards dynamic maximazation of oxygen yield in an elevated-pressure air separation unit  

SciTech Connect

In a typical air separation unit (ASU) utilizing either a simple gaseous oxygen (GOX) cycle or a pumped liquid oxygen (PLOX) cycle, the flowrate of liquid nitrogen (LN2) stream connecting high-pressure and low-pressure ASU columns plays an important role in the total oxygen yield. It has been observed that this yield reaches a maximum at a certain optimal flowrate of LN2 stream. At nominal full-load operation, the flowrate of LN2 stream is maintained near this optimum value, whereas at part-load conditions this flowrate is typically modified in proportion with the load-change (oxygen demand) through a ratio/feed-forward controller. Due to nonlinearity in the entire ASU process, the ratio-modified LN2 flowrate does not guarantee an optimal oxygen yield at part-load conditions. This is further exacerbated when process disturbances in form of “cold-box” heat-leaks enter the system. To address this problem of dynamically maximizing the oxygen yield while the ASU undergoes a load-change and/or a process disturbance, a multiple model predictive control (MMPC) algorithm is proposed. This approach has been used in previous studies to handle large ramp-rates of oxygen demand posed by the gasifier in an IGCC plant. In this study, the proposed algorithm uses linear step-response “blackbox” models surrounding the operating points corresponding to maximum oxygen yield points at different loads. It has been shown that at any operating point of the ASU, the MMPC algorithm, through model-weight calculation based on plant measurements, naturally and continuously selects the dominant model(s) corresponding to the current plant state, while making control-move decisions that approach the maximum oxygen yield point. This dynamically facilitates less energy consumption in form of compressed feed-air compared to a simple ratio control during load-swings. In addition, since a linear optimization problem is solved at each time step, the approach involves much less computational cost compared to a firstprinciple based nonlinear MPC. Introduction

Mahapatra, P.; Zitney, S.; Bequette, B. Wayne

2012-01-01T23:59:59.000Z

253

System Definition Document: Reactor Data Necessary for Modeling Plutonium Disposition in Catawba Nuclear Station Units 1 and 2  

Science Conference Proceedings (OSTI)

The US Department of Energy (USDOE) has contracted with Duke Engineering and Services, Cogema, Inc., and Stone and Webster (DCS) to provide mixed-oxide (MOX) fuel fabrication and reactor irradiation services in support of USDOE's mission to dispose of surplus weapons-grade plutonium. The nuclear station units currently identified as mission reactors for this project are Catawba Units 1 and 2 and McGuire Units 1 and 2. This report is specific to Catawba Nuclear Station Units 1 and 2, but the details and materials for the McGuire reactors are very similar. The purpose of this document is to present a complete set of data about the reactor materials and components to be used in modeling the Catawba reactors to predict reactor physics parameters for the Catawba site. Except where noted, Duke Power Company or DCS documents are the sources of these data. These data are being used with the ORNL computer code models of the DCS Catawba (and McGuire) pressurized-water reactors.

Ellis, R.J.

2000-11-01T23:59:59.000Z

254

Unit Conversion  

Science Conference Proceedings (OSTI)

Unit Conversion. ... Unit Conversion Example. "If you have an amount of unit of A, how much is that in unit B?"; Dimensional Analysis; ...

2012-12-04T23:59:59.000Z

255

Changes in 20th century extreme temperature and precipitation over the western United States based on observations and regional climate model simulations  

Science Conference Proceedings (OSTI)

Trends in extreme temperature and precipitation in two regional climate model simulations forced by two global climate models are compared with observed trends over the western United States. The observed temperature extremes show substantial and ...

Valérie Dulière; Yongxin Zhang; Eric P. Salathé Jr.

256

A Model to Estimate the Time of Observation Bias Associated with Monthly Mean Maximum, Minimum and Mean Temperatures for the United States  

Science Conference Proceedings (OSTI)

Hourly data for 79 stations in the United States are used to develop an empirical model which can be used to estimate the time of observation bias associated with different observation schedules. The model is developed for both maximum and ...

Thomas R. Karl; Claude N. Williams Jr.; Pamela J. Young; Wayne M. Wendland

1986-02-01T23:59:59.000Z

257

A meso-scale unit-cell based material model for the single-ply flexible-fabric armor M. Grujicic a,*, W.C. Bell a  

E-Print Network (OSTI)

A meso-scale unit-cell based material model for the single-ply flexible-fabric armor M. Grujicic a April 2008 Accepted 12 February 2009 Available online 20 February 2009 Keywords: Flexible armor Meso-scale unit-cell based material model for a prototypical plain-woven single-ply flexible armor is developed

Grujicic, Mica

258

Modeling the Behavior of Formate, Acetate, and Carbon Dioxide in Water/Steam Cycles  

SciTech Connect

Organic substances persist in high-temperature aqueous environments for varying periods of tiem depending on temperature, pH, contact with solid surfaces, and other factors. Since carboxylic acids and CO{sub 2} affect the pH and can potentially play specific roles in the promotion of inhibition of turbine corrosion, it is important to be able to predict the amounts of these substances that are transferred to steam and the composition of the early condensate as a function of condesnation ratio for various boiler chemistries. Such predictions can only be made using a speciated model including all the solutes. Example calculations for AVT and OT chemistry show complex relationships between early condensate enrichment ratios and boiler pressure, boiler water composition, and condensation ratio. Even small amounts of sodium and chloride below 0.1 {mu}g {center_dot} kg{sup -1} in the steam are relevant to early condensate pH and carboxylic acid concentration. The calculations show that the enrichment of the early condensate relative to steam is typically 10 times greater for formate than for acetate.

Gruszkiewicz, Miroslaw {Mirek} S [ORNL; Palmer, Donald [ORNL

2004-01-01T23:59:59.000Z

259

Indirect-fired gas turbine dual fuel cell power cycle  

DOE Patents (OSTI)

The present invention relates generally to an integrated fuel cell power plant, and more specifically to a combination of cycles wherein a first fuel cell cycle tops an indirect-fired gas turbine cycle and a second fuel cell cycle bottoms the gas turbine cycle so that the cycles are thermally integrated in a tandem operating arrangement. The United States Government has rights in this invention pursuant to the employer-employee relationship between the United States Department of Energy and the inventors.

Micheli, P.L.; Williams, M.C.; Sudhoff, F.A.

1998-04-01T23:59:59.000Z

260

System dynamics based models for selecting HVAC systems for office buildings: a life cycle assessment from carbon emissions perspective.  

E-Print Network (OSTI)

??This study aims to explore the life cycle environmental impacts of typical heating ventilation and air condition (HVAC) systems including variable air volume (VAV) system,… (more)

Chen, S

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Emergence of Fusion/Fission Cycling and Self-Organized Criticality from a Simulation Model of Early Complex Polities  

E-Print Network (OSTI)

H. 1999, Chiefdoms and the Fission-Fusion Process, AmericanEmergence of Fusion/Fission Cycling and Self-Organizedthe fusion and subsequent fission of dynamic political

Griffin, Arthur F

2011-01-01T23:59:59.000Z

262

united stadium. united station.  

E-Print Network (OSTI)

??DC United is one of Major League Soccerâs most decorated franchises, yet it still plays its home games within the crumbling confines of RFK Stadium.… (more)

Groff, David R.

2011-01-01T23:59:59.000Z

263

Factors influencing anthropogenic carbon dioxide uptake in the North Atlantic in models of the ocean carbon cycle  

SciTech Connect

The uptake and storage of anthropogenic carbon in the North Atlantic is investigated using different configurations of ocean general circulation/carbon cycle models. We investigate how different representations of the ocean physics in the models, which represent the range of models currently in use, affect the evolution of CO{sub 2} uptake in the North Atlantic. The buffer effect of the ocean carbon system would be expected to reduce ocean CO{sub 2} uptake as the ocean absorbs increasing amounts of CO{sub 2}. We find that the strength of the buffer effect is very dependent on the model ocean state, as it affects both the magnitude and timing of the changes in uptake. The timescale over which uptake of CO{sub 2} in the North Atlantic drops to below preindustrial levels is particularly sensitive to the ocean state which sets the degree of buffering; it is less sensitive to the choice of atmospheric CO{sub 2} forcing scenario. Neglecting physical climate change effects, North Atlantic CO{sub 2} uptake drops below preindustrial levels between 50 and 300 years after stabilisation of atmospheric CO{sub 2} in different model configurations. Storage of anthropogenic carbon in the North Atlantic varies much less among the different model configurations, as differences in ocean transport of dissolved inorganic carbon and uptake of CO{sub 2} compensate each other. This supports the idea that measured inventories of anthropogenic carbon in the real ocean cannot be used to constrain the surface uptake. Including physical climate change effects reduces anthropogenic CO{sub 2} uptake and storage in the North Atlantic further, due to the combined effects of surface warming, increased freshwater input, and a slowdown of the meridional overturning circulation. The timescale over which North Atlantic CO{sub 2} uptake drops to below preindustrial levels is reduced by about one-third, leading to an estimate of this timescale for the real world of about 50 years after the stabilisation of atmospheric CO{sub 2}. In the climate change experiment, a shallowing of the mixed layer depths in the North Atlantic results in a significant reduction in primary production, reducing the potential role for biology in drawing down anthropogenic CO{sub 2}.

Smith, R.S.; Marotzke, J. [Max Planck Institute for Meteorology, Hamburg (Germany)

2008-09-30T23:59:59.000Z

264

An Electricity-focused Economic Input-output Model: Life-cycle Assessment and Policy Implications of Future Electricity Generation Scenarios  

E-Print Network (OSTI)

chains and emission factors for the generation, transmission and distribution portions of the electricityAn Electricity-focused Economic Input-output Model: Life-cycle Assessment and Policy Implications of Future Electricity Generation Scenarios Joe Marriott Submitted in Partial Fulfillment of the Requirements

265

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

United States Department of Energy Southeastern Power Administration Wholesale Power Rate Schedule JW-2-F Availability: This rate schedule shall be available to the Florida Power Corporation (or Progress Energy Florida, hereinafter called the Company). Applicability: This rate schedule shall be applicable to electric energy generated at the Jim Woodruff Project (hereinafter called the Project) and sold to the Company in wholesale quantities. Points of Delivery: Power sold to the Company by the Government will be delivered at the connection of the Company's transmission system with the Project bus. Character of Service: Electric power delivered to the Company will be three-phase alternating current at a nominal frequency of 60 cycles per second.

266

Transient Future Climate over the Western United States Using a Regional Climate Model  

Science Conference Proceedings (OSTI)

Regional climate models (RCMs) have improved our understanding of the effects of global climate change on specific regions. The need for realistic forcing has led to the use of fully coupled global climate models (GCMs) to produce boundary ...

Mark A. Snyder; Lisa C. Sloan

2005-07-01T23:59:59.000Z

267

General and Partial Equilibrium Modeling of Sectoral Policies to Address Climate Change in the United States  

SciTech Connect

This document provides technical documentation for work using detailed sectoral models to calibrate a general equilibrium analysis of market and non-market sectoral policies to address climate change. Results of this work can be found in the companion paper, ?Modeling Costs of Economy-wide versus Sectoral Climate Policies Using Combined Aggregate-Sectoral Models?.

Pizer, William; Burtraw, Dallas; Harrington, Winston; Newell, Richard; Sanchirico, James; Toman, Michael

2003-03-31T23:59:59.000Z

268

Modeling unit cell interactions for the microstructure of a heterogeneous explosive: detonation diffraction past an inert sphere  

SciTech Connect

We describe an approach being used to model multi-phase blast explosive, that is mostly condensed explosive by volume with inert embedded particles. The asymptotic theory of detonation shock dynamics is used to describe the detonation shock propagation in the explosive. The shock motion rule in the explosive requires that the shock move at a normal speed that depends on the shock curvature. The angle that the shock makes with the particle boundary is also prescribed. We describe theory that can be used to predict the behavior of a collection of such detonation shock/particle interactions in the larger aggregate. A typical unit cell problem of a detonation shock diffraction over a sphere is analyzed by analytical and numerical means and the properties of an ensemble of such unit cell problems is discussed with implications for the macroscopic limiting behavior of the heterogeneous explosive.

Bdzil, John B [Los Alamos National Laboratory; Stewart, Donald S [Los Alamos National Laboratory; Walter, John W [Los Alamos National Laboratory; Aida, Toru [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

269

AN AGGREGATED VECTORIAL MODEL OF PETROLEUM FLOW IN THE UNITED STATES  

E-Print Network (OSTI)

DATA SOURCES: Collected from crude oil and petroleum productPetroleum product imports form an additional source thatpetroleum model:(a)- Storage; (b)- Transportation; (c)- Source; (

Krishnan, V. V.

2011-01-01T23:59:59.000Z

270

A Classic Model in a Low Fertility Context: The Proximate Determinants of Fertility in South Korea and the United States  

E-Print Network (OSTI)

John Bongaarts' proximate determinants model of fertility has accounted for over 90 percent of variation in the total fertility rate (TFR) of primarily developing nations and historical populations. Recently, dramatically low fertility rates across the globe have raised questions regarding whether this model could be applied to exclusively below-replacement nations. This study follows Knodel, Chamratrithirong, and Debavalya's 1987 analysis of fertility decline in Thailand by conducting in-depth case studies of the proximate determinants in two low fertility countries over time: South Korea, where fertility is well below the level of replacement, and the United States, where fertility has hovered around replacement level for many years. Then, the fertility-inhibiting effect of the proximate determinants is assessed by comparing the quantitative index representing each determinant measured in the 1960s/1970s with its measurement in the 2000s. For both years, I consider the fertility level that would prevail in the determinant's presence as well as the level that would exist in its absence. Finally, I use each of the indices to calculate the TFR and assess how the strength of the model varies over time in the two countries. Ultimately, results indicate that the proximate determinants model does not offer a clean picture of the fertility level in either South Korea or the United States; when trends uncovered by the case studies are compared to the results of the quantitative analysis, a number of inconsistencies are revealed. This suggests that certain components in the model may need to be respecified for more effective application in low-fertility contexts. However, that is not to say that it offers no insight into fertility at all or that it is no longer a useful tool. On the contrary, it is shown that the proximate determinants model holds a lot of potential for analysis in low-fertility nations. The implications of these results, as well as the need for improvements in international data collection efforts, are also discussed.

Guarneri, Christine E.

2010-05-01T23:59:59.000Z

271

THREE-DIMENSIONAL FEATURES OF THE OUTER HELIOSPHERE DUE TO COUPLING BETWEEN THE INTERSTELLAR AND INTERPLANETARY MAGNETIC FIELDS. IV. SOLAR CYCLE MODEL BASED ON ULYSSES OBSERVATIONS  

Science Conference Proceedings (OSTI)

The solar cycle has a profound influence on the solar wind (SW) interaction with the local interstellar medium (LISM) on more than one timescales. Also, there are substantial differences in individual solar cycle lengths and SW behavior within them. The presence of a slow SW belt, with a variable latitudinal extent changing within each solar cycle from rather small angles to 90 Degree-Sign , separated from the fast wind that originates at coronal holes substantially affects plasma in the inner heliosheath (IHS)-the SW region between the termination shock (TS) and the heliopause (HP). The solar cycle may be the reason why the complicated flow structure is observed in the IHS by Voyager 1. In this paper, we show that a substantial decrease in the SW ram pressure observed by Ulysses between the TS crossings by Voyager 1 and 2 contributes significantly to the difference in the heliocentric distances at which these crossings occurred. The Ulysses spacecraft is the source of valuable information about the three-dimensional and time-dependent properties of the SW. Its unique fast latitudinal scans of the SW regions make it possible to create a solar cycle model based on the spacecraft in situ measurements. On the basis of our analysis of the Ulysses data over the entire life of the mission, we generated time-dependent boundary conditions at 10 AU from the Sun and applied our MHD-neutral model to perform a numerical simulation of the SW-LISM interaction. We analyzed the global variations in the interaction pattern, the excursions of the TS and the HP, and the details of the plasma and magnetic field distributions in the IHS. Numerical results are compared with Voyager data as functions of time in the spacecraft frame. We discuss solar cycle effects which may be reasons for the recent decrease in the TS particles (ions accelerated to anomalous cosmic-ray energies) flux observed by Voyager 1.

Pogorelov, N. V.; Zank, G. P. [Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Suess, S. T. [National Space Science and Technology Center, Huntsville, AL 35805 (United States); Borovikov, S. N. [Center for Space Plasma and Aeronomic Research, University of Alabama in Huntsville, 320 Sparkman Dr., Huntsville, AL 35805 (United States); Ebert, R. W.; McComas, D. J., E-mail: np0002@uah.edu [Southwest Research Institute, San Antonio, TX 78227 (United States)

2013-07-20T23:59:59.000Z

272

A Dynamic Probability Model of Hurricane Winds in Coastal Counties of the United States  

Science Conference Proceedings (OSTI)

The authors develop and apply a model that uses hurricane-experience data in counties along the U.S. hurricane coast to give annual exceedence probabilities to maximum tropical cyclone wind events. The model uses a maximum likelihood estimator to ...

Thomas Jagger; James B. Elsner; Xufeng Niu

2001-05-01T23:59:59.000Z

273

Evaluation of Alberta Hail Growth Model Using Severe Hail Proximity Soundings from the United States  

Science Conference Proceedings (OSTI)

A one-dimensional, coupled hail and cloud model (HAILCAST) is tested to assess its ability to predict hail size. The model employs an ensemble approach when forecasting maximum hail size, uses a sounding as input, and can be run in seconds on an ...

Ryan Jewell; Julian Brimelow

2009-12-01T23:59:59.000Z

274

Impact of Model Resolution on the Prediction of Summer Precipitation over the United States and Mexico  

Science Conference Proceedings (OSTI)

Summer seasonal simulations for selected years were performed using the NCEP Global Forecast System (GFS) at high (T126L28) and low (T62L28) resolutions, and the NCEP 80-km regional spectral model (RSM) nested in the T62 model outputs (RSM80/T62)...

Kingtse C. Mo; Jae-Kyung Schemm; H. M. H. Juang; R. Wayne Higgins; Yucheng Song

2005-09-01T23:59:59.000Z

275

Improving the accuracy of flow units prediction through two committee machine models: An example from the South Pars Gas Field, Persian Gulf Basin, Iran  

Science Conference Proceedings (OSTI)

Intelligent reservoir characterization is a prerequisite study for development of oil and gas fields. Hydraulic flow units are mappable portions of hydrocarbon-bearing rocks that control fluid flow, and their modeling allows an accurate understanding ... Keywords: Committee machine, Flow units, Fuzzy logic, Genetic algorithm, Iran, Neural network, Neuro-fuzzy, South Pars Gas Field

Javad Ghiasi-Freez; Ali Kadkhodaie-Ilkhchi; Mansur Ziaii

2012-09-01T23:59:59.000Z

276

Modeling and optimization of a combined cycle Stirling-ORC system and design of an integrated microchannel Stirling heat rejector.  

E-Print Network (OSTI)

??The performance of a combined Stirling-ORC power cycle is evaluated, and an integrated microchannel heat exchanger is designed as an annular cold-side heat rejector for… (more)

[No author

2010-01-01T23:59:59.000Z

277

The Structure and Nonlinear Evolution of Synoptic Scale Cyclones: Life Cycle Simulations with a Cloud-Scale Model  

Science Conference Proceedings (OSTI)

High resolution simulations of idealized baroclinic wave life cycles on both the f-plane and the ?-plane are performed. The anelastic, nonhydrostatic equations are employed in these analyses and motions are assumed dry adiabatic and inviscid, ...

S. M. Polavarapu; W. R. Peltier

1990-11-01T23:59:59.000Z

278

Mathematical Modeling of Perfect Decoupled Control System and Its Application: A Reverse Osmosis Desalination Industrial-Scale Unit  

E-Print Network (OSTI)

This short paper outlines the computer simulation using real data of a decoupled control system for a desalination unit. The control strategy incorporated a perfect decoupled controller for the control of the fresh water flow and conductivity. The model was estimated using real data and empirical tools instead of mass balances. The success is demonstrated in the reduction of wide fluctuations in the variables of the process and decreasing of the sensibility to the changes of pressure and/or pH and allows predicting problems of quality of water and waste of energy in the future. 1.

C. Riverol; V. Pilipovik

2004-01-01T23:59:59.000Z

279

This is a 1D model of an active magnetic regenerative refrigerator (AMRR) that was developed in MATLAB. The model uses cycle inputs such as the fluid mass flow and  

E-Print Network (OSTI)

temperature profile of the fluid and regenerator. Using the temperature profiles, the cooling load produced in MATLAB. The model uses cycle inputs such as the fluid mass flow and magnetic field profiles, fluid external hardware. The model starts from an initial temperature profile for the regenerator and fluid

Wisconsin at Madison, University of

280

MODELING TRANSPORT IN THE DOWN GRADIENT PORTION OF THE 200-PO-1 OPERABLE UNIT AT THE HANFORD SITE  

SciTech Connect

Remedial Investigations are underway for the 200-PO-l Operable Unit (OU) at the U.S. Department of Energy's Hanford Site in Washington State. To support the baseline risk assessment and evaluation of remedial alternatives, fate and transport modeling is being conducted to predict the future concentration of contaminants of potential concern in the 200-PO-1 OU. This study focuses on modeling the 'down gradient' transport of those contaminants that migrate beyond the 3-D model domain selected for performing detailed 'source area' modeling within the 200-PO-1 OU. The down gradient portion is defined as that region of the 200-PO-1 OU that is generally outside the 200 Area (considered 'source area') of the Hanford Site. A 1-D transport model is developed for performing down gradient contaminant fate and transport modeling. The 1-D transport model is deemed adequate based on the inferred transport pathway of tritium in the past and the observation that most of the contaminant mass remains at or near the water table within the unconfined aquifer of the Hanford Formation and the Cold-Creek/Pre-Missoula Gravel unit. The Pipe Pathway feature of the GoldSim software is used to perform the calculations. The Pipe Pathway uses a Laplace transform approach to provide analytical solutions to a broad range of advection-dominated mass transport systems involving one-dimensional advection, longitudinal dispersion, retardation, decay and ingrowth, and exchanges with immobile storage zones. Based on the historical concentration distribution data for the extensive tritium plume in this area, three Pipe Pathways are deemed adequate for modeling transport of contaminants. Each of these three Pipe Pathways is discretized into several zones, based on the saturated thickness variation in the unconfined aquifer and the location of monitoring wells used for risk assessment calculation. The mass fluxes of contaminants predicted to exit the source area model domain are used as an input to the down gradient model, while the flow velocities applied are based on the present-day hydraulic gradients and estimation of hydraulic conductivity in the unconfined aquifer. The results of the calculation indicate that the future concentrations of contaminants of potential concern in the down gradient portion of the 200-PO-1 OU declines with time and distance.

MEHTA S; ALY AH; MILLER CW; MAYENNA A

2009-12-03T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Modeling the Long-Term Market Penetration of Wind in the United States  

NLE Websites -- All DOE Office Websites (Extended Search)

Long-Term Long-Term Market Penetration of Wind in the United States July 2003 * NREL/CP-620-34469 W. Short, N. Blair, D. Heimiller, and V. Singh Presented at the American Wind Energy Association (AWEA) WindPower 2003 Conference Austin, Texas May 21, 2003 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute * Battelle * Bechtel Contract No. DE-AC36-99-GO10337 NOTICE The submitted manuscript has been offered by an employee of the Midwest Research Institute (MRI), a contractor of the US Government under Contract No. DE-AC36-99GO10337. Accordingly, the US Government and MRI retain a nonexclusive royalty-free license to publish or reproduce the published

282

Proceedings: 1990 Fossil Plant Cycling Conference  

Science Conference Proceedings (OSTI)

With the prospect of much new baseload generation from independent power producers and other qualifying facilities, the cycling capability of utility fossil-fired units originally designed for baseload operation is an ongoing concern. The 30 papers presented at EPRI's fourth cycling conference offer new insights into unit condition and life assessment, conversion, operation, and control as well as some storage-based alternatives to cycling.

1992-02-01T23:59:59.000Z

283

Calibration of LaD Model in the Northeast United States Using Observed Annual Streamflow  

Science Conference Proceedings (OSTI)

Calibration of land surface models improves simulations of surface water and energy fluxes and provides important information for water resources management. However, most calibration studies focus on local sites and/or small catchments because ...

Y. Xia

2007-10-01T23:59:59.000Z

284

Impact of Domain Size on Modeled Ozone Forecast for the Northeastern United States  

Science Conference Proceedings (OSTI)

This study investigates the impact of model domain extent and the specification of lateral boundary conditions on the forecast quality of air pollution constituents in a specific region of interest. A developmental version of the national Air ...

Pius Lee; Daiwen Kang; Jeff McQueen; Marina Tsidulko; Mary Hart; Geoff DiMego; Nelson Seaman; Paula Davidson

2008-02-01T23:59:59.000Z

285

One-Dimensional Earth Resistivity Models for Selected Areas of Continental United States & Alaska  

Science Conference Proceedings (OSTI)

Numerical modeling of the effect of geomagnetically induced currents (GIC) in power transmission networks involves two components: geophysical and technological.  The geophysical component deals with the calculation of a geoelectric field at locations along the transmission network.  (The need for the geophysical component in the modeling process in the industry is due to the lack of regular recordings of the geoelectric field, either at geomagnetic observatories or along power ...

2012-12-06T23:59:59.000Z

286

Evaluation of the Surface Climatology over the Conterminous United States in the North American Regional Climate Change Assessment Program Hindcast Experiment Using a Regional Climate Model Evaluation System  

Science Conference Proceedings (OSTI)

Surface air temperature, precipitation, and insolation over the conterminous United States region from the North American Regional Climate Change Assessment Program (NARCCAP) regional climate model (RCM) hindcast study are evaluated using the Jet ...

Jinwon Kim; Duane E. Waliser; Chris A. Mattmann; Linda O. Mearns; Cameron E. Goodale; Andrew F. Hart; Dan J. Crichton; Seth McGinnis; Huikyo Lee; Paul C. Loikith; Maziyar Boustani

2013-08-01T23:59:59.000Z

287

Multiscale Interactions in the Life Cycle of a Tropical Cyclone Simulated in a Global Cloud-System-Resolving Model. Part I: Large-Scale and Storm-Scale Evolutions  

Science Conference Proceedings (OSTI)

The Nonhydrostatic Icosahedral Atmospheric Model (NICAM), a global cloud-system-resolving model, successfully simulated the life cycle of Tropical Storm Isobel that formed over the Timor Sea in the austral summer of 2006. The multiscale ...

Hironori Fudeyasu; Yuqing Wang; Masaki Satoh; Tomoe Nasuno; Hiroaki Miura; Wataru Yanase

2010-12-01T23:59:59.000Z

288

Steam Turbine and Generator Designs for Combined-Cycle Applications: Durability, Reliability, and Procurement Considerations  

Science Conference Proceedings (OSTI)

Combined-cycle power plants are currently preferred for new power generation capacity in much of the world, particularly in the United States. Steam turbines and electrical generators are vital components affecting plant performance and reliability. Over 90 percent of the world's combined-cycle steam turbines are provided by six major manufacturers: Alstom, General Electric, Siemens-Westinghouse, Mitsubishi, Toshiba, and Hitachi. This report provides information on their model offerings and consideration...

2003-03-18T23:59:59.000Z

289

HTTR criticality calculations with SCALE6: Studies of various geometric and unit-cell options in modeling  

Science Conference Proceedings (OSTI)

The fuel element of the High Temperature Engineering Test Reactor (HTTR) presents a doubly heterogeneous geometry, where tiny TRISO fuel particles dispersed in a graphite matrix form the fuel region of a cylindrical fuel rod, and a number of fuel rods together with moderator or reflector then constitute the lattice design of the core. In this study, a series of full-core HTTR criticality calculations were performed with the SCALE6 code system using various geometric and unit-cell options in order to systematically investigate their effects on neutronic analysis. Two geometric descriptions (ARRAY or HOLE) in SCALE6 can be used to construct a complicated and repeated model. The result shows that eliminating the use of HOLE in the HTTR geometric model can save the computation time by a factor of 4. Four unit-cell treatments for resonance self-shielding corrections in SCALE6 were tested to create problem-specific multigroup cross sections for the HTTR core model. Based on the same ENDF/B-VII cross-section library, their results were evaluated by comparing with continuous-energy calculations. The comparison indicates that the INFHOMMEDIUM result overestimates the system multiplication factor (k{sub eff}) by 55 mk, whereas the LATTICECELL and MULTIREGION treatments predict the k{sub eff} values with similar biases of approximately 10 mk overestimation. The DOUBLEHET result shows a more satisfactory agreement, about 4.2 mk underestimation in the k{sub eff} value. In addition, using cell-weighted cross sections instead of an explicit modeling of TRISO particles in fuel region can further reduce the computation time by a factor of 5 without sacrificing accuracy. (authors)

Wang, J. Y.; Chiang, M. H.; Sheu, R. J.; Liu, Y. W. H. [Inst. of Nuclear Engineering and Science, National Tsing Hua Univ., Hsinchu 30013, Taiwan (China)

2012-07-01T23:59:59.000Z

290

Simulation model of a rotary expander of a small cogeneration unit  

Science Conference Proceedings (OSTI)

Today, steam engines are used for special purposes only, for example to reduce steam pressure in pressure reduction stations, where they replace the traditional and inefficient throttling process. Throttling is the most used way to control the pressure ... Keywords: cogeneration, modeling, simulation, steam engine

Evžen Thöndel

2007-10-01T23:59:59.000Z

291

Regression Model Predicting Appraised Unit Value of Land in San Francisco County from Number of and Distance to Public Transit Stops using GIS  

E-Print Network (OSTI)

The objective of this study is to develop a quantifying model that predicts the appraised unit value of parcels in San Francisco County based on number of LEED-NC Public Transportation Access (PTA) qualified bus, light rail and commuter rail stops, distance to closest bus, light rail and commuter rail stops, zoning class and parcel size. As a population of interest, San Francisco County was chosen since it is known as a region having well-organized transportation systems including bus, light rail and commuter rail systems. According to the correlation results, for mixed zone, an appraised unit value increases as the number of LEED qualified transit stops increases (bus, light rail, and commuter rail). In addition, the appraised unit value increases as the distance to LEED qualified bus stops light rail stops decreases. For residential zone, the appraised unit value increases as the number of LEED qualified bus and light rail stations increases. Furthermore, the appraised unit value increases as the distance to LEED qualified bus stops decreases. When it comes to the predictive regression model for mixed zone, the adjusted R-square of the transformed model was 0.713, which indicates that 71.3 percent variability in transformed unit value of parcels could be explained by these variables. In addition, for the predictive model of residential zone, the adjusted R-square for the model was 0.622 thus the independent variables together accounted for 62.2 percent variability in the transformed unit value of parcels. The predicting models for mixed and residential zones were significant that suggests that the components of LEED-NC PTA criteria, number and distance from parcels, this could affect land development strategies. In addition, an appraised unit value of parcels in San Francisco County can be estimated by using the predictive models developed in this study. Therefore, the findings of this study could encourage real-estate developers to site their projects according to the LEED-NC PTA criteria.

Son, Kiyoung

2012-05-01T23:59:59.000Z

292

Update 5 to: A Dispersion Modeling Analysis of Downwash from Mirant's  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5 to: A Dispersion Modeling Analysis of Downwash from 5 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant: Modeling Cycling Units 1, 2 plus One Baseload Unit Update 5 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant: Modeling Cycling Units 1, 2 plus One Baseload Unit Docket No. EO-05-01: This report describes dispersion modeling performed for simultaneous operation of one baseload unit and two cycling units at Mirant's Potomac River Generating Station (PRGS). This mode of operation is also referred to as Option A in Mirant Potomac River LLC's December 30, 2005 letter to the U.S. Department of Energy regarding District of Columbia Public Service Commission, Docket No. EO-05- 01. The modeling was performed according to the Protocol approved by the Virginia Department of

293

The DOE water cycle pilot study.  

SciTech Connect

In 1999, the U.S. Global Change Research Program (USGCRP) formed a Water Cycle Study Group (Hornberger et al. 2001) to organize research efforts in regional hydrologic variability, the extent to which this variability is caused by human activity, and the influence of ecosystems. The USGCRP Water Cycle Study Group was followed by a U.S. Department of Energy (DOE) Water Cycle Research Plan (Department of Energy 2002) that outlined an approach toward improving seasonal-to-interannual hydroclimate predictability and closing a regional water budget. The DOE Water Cycle Research Plan identified key research areas, including a comprehensive long-term observational database to support model development, and to develop a better understanding of the relationship between the components of local water budgets and large scale processes. In response to this plan, a multilaboratory DOE Water Cycle Pilot Study (WCPS) demonstration project began with a focus on studying the water budget and its variability at multiple spatial scales. Previous studies have highlighted the need for continued efforts to observationally close a local water budget, develop a numerical model closure scheme, and further quantify the scales in which predictive accuracy are optimal. A concerted effort within the National Oceanic and Atmospheric Administration (NOAA)-funded Global Energy and Water Cycle Experiment (GEWEX) Continental-scale International Project (GCIP) put forth a strategy to understand various hydrometeorological processes and phenomena with an aim toward closing the water and energy budgets of regional watersheds (Lawford 1999, 2001). The GCIP focus on such regional budgets includes the measurement of all components and reduction of the error in the budgets to near zero. To approach this goal, quantification of the uncertainties in both measurements and modeling is required. Model uncertainties within regional climate models continue to be evaluated within the Program to Intercompare Regional Climate Simulations (Takle et al. 1999), and model uncertainties within land surface models are being evaluated within the Program to Intercompare Land Surface Schemes (e.g., Henderson-Sellers 1993; Wood et al. 1998; Lohmann et al. 1998). In the context of understanding the water budget at watershed scales, the following two research questions that highlight DOE's unique water isotope analysis and high-performance modeling capabilities were posed as the foci of this pilot study: (1) Can the predictability of the regional water budget be improved using high-resolution model simulations that are constrained and validated with new hydrospheric water measurements? (2) Can water isotopic tracers be used to segregate different pathways through the water cycle and predict a change in regional climate patterns? To address these questions, numerical studies using regional atmospheric-land surface models and multiscale land surface hydrologic models were generated and, to the extent possible, the results were evaluated with observations. While the number of potential processes that may be important in the local water budget is large, several key processes were examined in detail. Most importantly, a concerted effort was made to understand water cycle processes and feedbacks at the land surface-atmosphere interface at spatial scales ranging from 30 m to hundreds of kilometers. A simple expression for the land surface water budget at the watershed scale is expressed as {Delta}S = P + G{sub in} - ET - Q - G{sub out}, where {Delta}S is the change in water storage, P is precipitation, ET is evapotranspiration, Q is streamflow, G{sub in} is groundwater entering the watershed, and G{sub out} is groundwater leaving the watershed, per unit time. The WCPS project identified data gaps and necessary model improvements that will lead to a more accurate representation of the terms in Eq. (1). Table 1 summarizes the components of this water cycle pilot study and the respective participants. The following section provides a description of the surface observation and modeling sit

Miller, N. L.; King, A. W.; Miller, M. A.; Springer, E. P.; Wesely, M. L.; Bashford, K. E.; Conrad, M. E.; Costigan, K.; Foster, P. N.; Gibbs, H. K.; Jin, J.; Klazura, J.; Lesht, B. M.; Machavaram, M. V.; Pan, F.; Song, J.; Troyan, D.; Washngton-Allen, R. A.; Environmental Research; LBNL; ORNL; BNL; LANL

2005-03-01T23:59:59.000Z

294

Long-Term Modeling of Wind Energy in the United States  

SciTech Connect

An improved representation of wind energy has been developed for the ObjECTS MiniCAM integrated assessment modeling framework. The first version of this wind model was used for the CCTP scenarios, where wind accounts for between 9% and 17% of U.S. electricity generation by 2095. Climate forcing stabilization policies tend to increase projected deployment. Accelerated technological development in wind electric generation can both increase output and reduce the costs of wind energy. In all scenarios, wind generation is constrained by its costs relative to alternate electricity sources, particularly as less favorable wind farm sites are utilized. These first scenarios were based on exogenous resource estimates that do not allow evaluation of resource availability assumptions. A more detailed representation of wind energy is under development that uses spatially explicit resource information and explicit wind turbine technology characteristics.

Kyle, G. Page; Smith, Steven J.; Wise, Marshall A.; Lurz, Joshua P.; Barrie, Daniel

2007-09-30T23:59:59.000Z

295

Modeling and Analysis of the Variability of the Water Cycle in the Upper Rio Grande Basin at High Resolution  

Science Conference Proceedings (OSTI)

Estimating the water budgets in a small-scale basin is a challenge, especially in the mountainous western United States, where the terrain is complex and observational data in the mountain areas are sparse. This manuscript reports on research ...

J. Li; X. Gao; S. Sorooshian

2007-08-01T23:59:59.000Z

296

Thermodynamic modeling of performance of a Miller cycle with engine speed and variable specific heat ratio of working fluid  

Science Conference Proceedings (OSTI)

The performance of an air standard Miller cycle is analyzed using finite-time thermodynamics. The results show that if the compression ratio is less than certain value, the increase of the value of the specific heat ratio will make the power output bigger. ... Keywords: Finite-time processes, Friction, Heat resistance, Internal irreversibility, Miller heat-engine

Rahim Ebrahimi

2011-09-01T23:59:59.000Z

297

Emergence of Fusion/Fission Cycling and Self-Organized Criticality from a Simulation Model of Early Complex Polities  

E-Print Network (OSTI)

Stanish, Charles, 2007. An Agent-based Model of Prehistoriccase of spatial agent- based models) that simulates wild

Griffin, Arthur F

2011-01-01T23:59:59.000Z

298

Carbon Cycle 2.0  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Carbon Cycle 2.0 Carbon Cycle 2.0 Pioneering science for sustainable energy solutions Artificial Photosynthesis Energy Storage Combustion Carbon Capture & Storage Developing World Efficiency Photovoltaics Biofuels Energy Analysis Climate Modeling Carbon Cycle 2.0 is... 1. A vision for * a global energy system integrated with the Earth's natural carbon cycles * an interactive Berkeley Lab environment with a shared sense of purpose 2. A program development plan that will allow us to deepen our capabilities and provide more opportunities to have impact 3. An attempt to integrate our basic research with applications using models of technology deployment constraints 4. Set of internal activities aimed at priming the effort

299

Phase II Transport Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, Revision 1  

Science Conference Proceedings (OSTI)

This document, the Phase II Frenchman Flat transport report, presents the results of radionuclide transport simulations that incorporate groundwater radionuclide transport model statistical and structural uncertainty, and lead to forecasts of the contaminant boundary (CB) for a set of representative models from an ensemble of possible models. This work, as described in the Federal Facility Agreement and Consent Order (FFACO) Underground Test Area (UGTA) strategy (FFACO, 1996; amended 2010), forms an essential part of the technical basis for subsequent negotiation of the compliance boundary of the Frenchman Flat corrective action unit (CAU) by Nevada Division of Environmental Protection (NDEP) and National Nuclear Security Administration Nevada Site Office (NNSA/NSO). Underground nuclear testing via deep vertical shafts was conducted at the Nevada Test Site (NTS) from 1951 until 1992. The Frenchman Flat area, the subject of this report, was used for seven years, with 10 underground nuclear tests being conducted. The U.S. Department of Energy (DOE), NNSA/NSO initiated the UGTA Project to assess and evaluate the effects of underground nuclear tests on groundwater at the NTS and vicinity through the FFACO (1996, amended 2010). The processes that will be used to complete UGTA corrective actions are described in the “Corrective Action Strategy” in the FFACO Appendix VI, Revision No. 2 (February 20, 2008).

Gregg Ruskuaff

2010-01-01T23:59:59.000Z

300

Summer Land–Atmosphere Coupling Strength over the United States: Results from the Regional Climate Model RegCM4–CLM3.5  

Science Conference Proceedings (OSTI)

This study investigates the land–atmosphere coupling strength during summer over the United States using the Regional Climate Model version 4 (RegCM4)–Community Land Model version 3.5 (CLM3.5). First, a 10-yr simulation driven with reanalysis ...

Rui Mei; Guiling Wang; Huanghe Gu

2013-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Legend Units  

Science Conference Proceedings (OSTI)

... Syntax: LEGEND UNIT units> where is an integer number or parameter in the range 1 to 100 that specifies the legend identifier; and ...

2013-11-27T23:59:59.000Z

302

The Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Cycle Print E-mail U.S. Carbon Cycle Science Program U.S. Carbon Cycle Science Program The U.S. Carbon Cycle Science Program, in consultation with the Carbon Cycle...

303

United Cool Air  

Energy.gov (U.S. Department of Energy (DOE))

While our process may start with a "basic model" it is seldom that we fabricate more than a few units that are identical.  Therefore, the definition of "basic model" has a large impact on the...

304

Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Cycle Carbon Cycle Latest Global Carbon Budget Estimates Including CDIAC Estimates Terrestrial Carbon Management Data Sets and Analyses Carbon Dioxide Emissions from Fossil-Fuel Consumption and Cement Manufacture, (2011) Annual Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) Monthly Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) Annual Fossil-Fuel CO2 Emissions: Global Stable Carbon Isotopic Signature (2012) Monthly Fossil-Fuel CO2 Emissions: Isomass (δ 13C) of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) AmeriFlux - Terrestrial Carbon Dioxide, Water Vapor, and Energy Balance Measurements Estimates of Monthly CO2 Emissions and Associated 13C/12C Values

305

Expeditious Data Center Sustainability, Flow, and Temperature Modeling: Life-Cycle Exergy Consumption Combined with a Potential Flow Based, Rankine Vortex Superposed, Predictive Method  

E-Print Network (OSTI)

strategy bypasses the vapor- compression cycle of the CRACis based on the same vapor-compression refrigeration cycle4.1, which shows the vapor-compression refrig- eration cycle

Lettieri, David

2012-01-01T23:59:59.000Z

306

Life Cycle Analysis: Integrated Gasification Combined Cycle (IGCC) Power Plant  

NLE Websites -- All DOE Office Websites (Extended Search)

Life Cycle Analysis: Integrated Life Cycle Analysis: Integrated Gasification Combined Cycle (IGCC) Power Plant Revision 2, March 2012 DOE/NETL-2012/1551 Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or

307

A Numerical Modeling System of the Hydrological Cycle for Estimation of Water Fluxes in the Huaihe River Plain Region, China  

Science Conference Proceedings (OSTI)

To analyze the water budget under human influences in the Huaihe River plain region in China, the authors have developed a numerical modeling system that integrates water flux algorithms into a platform created by coupling a soil moisture model ...

Xi Chen; Yongqin David Chen; Zhicai Zhang

2007-08-01T23:59:59.000Z

308

Ozone effects on net primary production and carbon sequestration in the conterminous United States using a biogeochemistry model  

E-Print Network (OSTI)

The effects of air pollution on vegetation may provide an important control on the carbon cycle that has not yet been widely considered. Prolonged exposure to high levels of ozone, in particular, has been observed to inhibit ...

Felzer, Benjamin Seth.; Kicklighter, David W.; Melillo, Jerry M.; Wang, Chien.; Zhuang, Qianlai.; Prinn, Ronald G.

309

Global Changes of the Water Cycle Intensity  

Science Conference Proceedings (OSTI)

In this study, numerical simulations of the twentieth-century climate are evaluated, focusing on the changes in the intensity of the global water cycle. A new model diagnostic of atmospheric water vapor cycling rate is developed and employed that ...

Michael G. Bosilovich; Siegfried D. Schubert; Gregory K. Walker

2005-05-01T23:59:59.000Z

310

Development and Testing of a Life Cycle Model and a Parameterization of Thin Mid-level Stratiform Clouds  

SciTech Connect

We used a cloud-resolving model (a detailed computer model of cloud systems) to evaluate and improve the representation of clouds in global atmospheric models used for numerical weather prediction and climate modeling. We also used observations of the atmospheric state, including clouds, made at DOE's Atmospheric Radiation Measurement (ARM) Program's Climate Research Facility located in the Southern Great Plains (Kansas and Oklahoma) during Intensive Observation Periods to evaluate our detailed computer model as well as a single-column version of a global atmospheric model used for numerical weather prediction (the Global Forecast System of the NOAA National Centers for Environmental Prediction). This so-called Single-Column Modeling approach has proved to be a very effective method for testing the representation of clouds in global atmospheric models. The method relies on detailed observations of the atmospheric state, including clouds, in an atmospheric column comparable in size to a grid column used in a global atmospheric model. The required observations are made by a combination of in situ and remote sensing instruments. One of the greatest problems facing mankind at the present is climate change. Part of the problem is our limited ability to predict the regional patterns of climate change. In order to increase this ability, uncertainties in climate models must be reduced. One of the greatest of these uncertainties is the representation of clouds and cloud processes. This project, and ARM taken as a whole, has helped to improve the representation of clouds in global atmospheric models.

Krueger, Steven K.

2008-03-03T23:59:59.000Z

311

Study of Possible Applications of Currently Available Building Information Modeling Tools for the Analysis of Initial Costs and Energy Costs for Performing Life Cycle Cost Analysis  

E-Print Network (OSTI)

The cost of design, construction and maintenance of facilities is on continual rise. The demand is to construct facilities which have been designed by apply life cycle costing principles. These principles have already given strong decision making power to the manufacturing industry. The need to satisfy the environmental sustainability requirements, improve operational effectiveness of buildings and apply value engineering principles has increased the dependency on life cycle costing analysis. The objective is to obtain economically viable solutions by analyzing the alternatives during the design of a building. Though the LCCA process is able to give the desired results, it does have some problems which have stood as hindrances to the more widespread use of the LCCA concept and method. The literature study has highlighted that the problem areas are the lack of frameworks or mechanisms for collecting and storing data and the complexity of LCCA exercise, which involves the analysis of a thousand of building elements and a number of construction-type options and maintenance activities for each building element at detailed design stages. Building Information Modeling has been able to repeatedly answer the questions raised by the AEC industry. The aim of this study is to identify the areas where BIM can be effectively applied to the LCCA process and become a part of the workflow. In this study, initially four LCCA case studies are read and evaluated from the point of view of understanding the method in which the life cycle costing principles have been applied. The purpose, the type alternatives examined, the process of analysis, the type of software used and the results are understood. An attempt has been carried out to understand the workflow of the LCCA process. There is a confidence that Building Information Modeling is capable of handling changes during the design, construction and maintenance phases of the project. Since applying changes to any kind of information of the building during LCC analysis forms the core, it has become necessary to use computer building models for examining these changes. The building modeling softwares are enumerated. The case studies have highlighted that the evaluation of the alternatives are primarily to achieve energy efficient solutions for the buildings. Applying these solutions involves high initial costs. The return on investment is the means by which these solutions become viable to the owners of the facilities. This is where the LCCA has been applied. Two of the important cost elements of the LCC analysis are initial costs and the operating costs of the building. The collaboration of these modeling tools with other estimating software where the initial costs of the building can be generated is studied. The functions of the quantity take-off tools and estimating tools along with the interoperability between these tools are analyzed. The operating costs are generated from the software that focuses on sustainability. And the currently used tools for performing the calculations of the life cycle costing analysis are also observed. The objective is to identify if the currently available BIM tools and software can help in obtaining LCCA results and are able to offset the hindrances of the process. Therefore, the software are studied from the point of view of ease of handling data and the type of data that can be generated. Possible BIM workflows are suggested depending on the functions of the software and the relationship between them. The study has aimed at taking a snapshot the current tools available which can aid the LCCA process. The research is of significance to the construction industry as it forms a precursor to the application of Building Information Modeling to the LCCA process as it shows that it has the capacity of overcoming the obstacles for life cycle costing. This opens a window to the possibility of applying BIM to LCCA and furthering this study.

Mukherji, Payal Tapandev

2010-12-01T23:59:59.000Z

312

The High Cycle Fatigue, Damage Initiation and Growth and Final ...  

Science Conference Proceedings (OSTI)

Energy Based Fatigue Life Prediction Models and Methods for Combined Low Cycle and High Cycle Fatigue · Fatigue Behavior of AM60B Subjected to Variable  ...

313

NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis...  

Open Energy Info (EERE)

Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 Baseline Model Jump to: navigation, search Name NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005...

314

Projections of Full-Fuel-Cycle Energy and Emissions Metrics  

E-Print Network (OSTI)

2012a. “Analysis & Projections - Models & Documentation. ”Projections of Full-Fuel-Cycle Energy and Emissions MetricsGovernment purposes. Projections of Full-Fuel-Cycle Energy

Coughlin, Katie

2013-01-01T23:59:59.000Z

315

English Units  

Science Conference Proceedings (OSTI)

English Units. A, B, C, D, E, F, G, H, I, J. 1, Steam Point Calculator: English Units, ... 6, Height of steam point apparatus above ground (ft.), 0, ft. ...

2011-12-22T23:59:59.000Z

316

Unit Conversions  

Science Conference Proceedings (OSTI)

... volume flow units, which contain "atm", assume that the gas is: ideal; at a pressure of 101325 Pa; at a temperature of 0 °C. Be aware that the unit "atm ...

2012-10-02T23:59:59.000Z

317

DESIGN OF HYBRID POWER GENERATION CYCLES EMPLOYING AMMONIA-WATER-CARBON DIOXIDE MIXTURES  

SciTech Connect

A power cycle generates electricity from the heat of combustion of fossil fuels. Its efficiency is governed by the cycle configuration, the operating parameters, and the working fluid. Typical. designs use pure water as the fluid. in the last two decades, hybrid cycles based on ammonia-water, and carbon-dioxide mixtures as the working fluid have been proposed. These cycles may improve the power generation efficiency of Rankine cycles by 15%. Improved efficiency is important for two reasons: it lowers the cost of electricity being produced, and by reducing the consumption of fossil fuels per unit power, it reduces the generation of environmental pollutants. The goal of this project is to develop a computational optimization-based method for the design and analysis of hybrid bottoming power cycles to minimize the usage of fossil fuels. The development of this methodology has been achieved by formulating this task as that of selecting the least cost power cycle design from all possible configurations. They employ a detailed thermodynamic property prediction package they have developed under a DOE-FETC grant to model working fluid mixtures. Preliminary results from this work suggest that a pure NH{sub 3} cycle outperforms steam or the expensive Kalina cycle.

Ashish Gupta

2002-06-01T23:59:59.000Z

318

Phase II Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0  

Science Conference Proceedings (OSTI)

This report documents pertinent transport data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU) 98. The purpose of this data compilation and related analyses is to provide the primary reference to support parameterization of the Phase II FF CAU transport model.

DeNovio, Nicole M.; Bryant, Nathan; King, Chrissi B.; Bhark, Eric; Drellack, Sigmund L.; Pickens, John F.; Farnham, Irene; Brooks, Keely M.; Reimus, Paul; Aly, Alaa

2005-04-01T23:59:59.000Z

319

Phase II Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0  

SciTech Connect

This report documents pertinent hydrologic data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU): CAU 98. The purpose of this data compilation and related analyses is to provide the primary reference to support the development of the Phase II FF CAU groundwater flow model.

John McCord

2004-12-01T23:59:59.000Z

320

Essays on Modeling the Economic Impacts of a Foreign Animal Disease on the United States Agricultural Sector  

E-Print Network (OSTI)

Foreign animal disease can cause serious damage to the United States (US) agricultural sector and foot-and-mouth disease (FMD), in particular, poses a serious threat. FMD causes death and reduced fecundity in infected animals, as well as significant economic consequences. FMD damages can likely be reduced through implementing pre-planned response strategies. Empirical studies have evaluated the economic consequences of alternative strategies, but typically employ simplified models. This dissertation seeks to improve US preparedness for avoiding and/or responding to an animal disease outbreak by addressing three issues related to strategy assessment in the context of FMD: integrated multi region economic and epidemic evaluation, inclusion of risk, and information uncertainty. An integrated economic/epidemic evaluation is done to examine the impact of various control strategies. This is done by combining a stochastic, spatial FMD simulation model with a national level, regionally disaggregated agricultural sector mathematical programming economic model. In the analysis, strategies are examined in the context of California's dairy industry. Alternative vaccination, disease detection and movement restriction strategies are considered as are trade restrictions. The results reported include epidemic impacts, national economic impacts, prices, regional producer impacts, and disease control costs under the alternative strategies. Results suggest that, including trade restrictions, the median national loss from the disease outbreak is as much as $17 billion when feed can enter the movement restriction zone. Early detection reduces the median loss and the standard deviation of losses. Vaccination does not reduce the median disease loss, but does have a smaller standard deviation of loss which would indicate it is a risk reducing strategy. Risk in foreign animal disease outbreaks is present from several sources; however, studies comparing alternative control strategies assume risk neutrality. In reality, there will be a desire to minimize the national loss as well as minimize the chance of an extreme outcome from the disease (i.e. risk aversion). We perform analysis on FMD control strategies using breakeven risk aversion coefficients in the context of an outbreak in the Texas High Plains. Results suggest that vaccination while not reducing average losses is a risk reducing strategy. Another issue related to risk and uncertainty is the response of consumers and domestic markets to the presence of FMD. Using a highly publicized possible FMD outbreak in Kansas that did not turn out to be true, we examine the role of information uncertainty in futures market response. Results suggest that livestock futures markets respond to adverse information even when that information is untrue. Furthermore, the existence of herding behavior and potential for momentum trading exaggerate the impact of information uncertainty related to animal disease.

Hagerman, Amy Deann

2009-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Bubble Pump Design for Single Pressure Absorption Refrigeration Cycles  

E-Print Network (OSTI)

A model has been developed for the design and optimization of a small bubble pump to be used in a single pressure absorption refrigeration cycle to lift the working fluid mixture against gravity and overcome flow friction. This analytical model is developed from two-phase flow fundamentals and incorporates the design parameters of the bubble pump. Parametric studies are carried out and a design optimization for maximum efficiency is performed for various operating conditions. Optimum efficiency is defined as the liquid pumped per unit of bubble pump heat input. The results show the optimum bubble pump tube diameter over a range of operating conditions.

Sam V. Shelton; Susan White Stewart

2002-01-01T23:59:59.000Z

322

A Hydrostratigraphic System for Modeling Groundwater Flow and Radionuclide Migration at the Corrective Action Unit Scale, Nevada Test Site and Surrounding Areas, Clark, Lincoln, and Nye Counties, Nevada  

SciTech Connect

Underground Test Area (UGTA) corrective action unit (CAU) groundwater flow and contaminant transport models of the Nevada Test Site (NTS) and vicinity are built upon hydrostratigraphic framework models (HFMs) that utilize the hydrostratigraphic unit (HSU) as the fundamental modeling component. The delineation and three-dimensional (3-D) modeling of HSUs within the highly complex geologic terrain that is the NTS requires a hydrostratigraphic system that is internally consistent, yet flexible enough to account for overlapping model areas, varied geologic terrain, and the development of multiple alternative HFMs. The UGTA CAU-scale hydrostratigraphic system builds on more than 50 years of geologic and hydrologic work in the NTS region. It includes 76 HSUs developed from nearly 300 stratigraphic units that span more than 570 million years of geologic time, and includes rock units as diverse as marine carbonate and siliciclastic rocks, granitic intrusives, rhyolitic lavas and ash-flow tuffs, and alluvial valley-fill deposits. The UGTA CAU-scale hydrostratigraphic system uses a geology-based approach and two-level classification scheme. The first, or lowest, level of the hydrostratigraphic system is the hydrogeologic unit (HGU). Rocks in a model area are first classified as one of ten HGUs based on the rock’s ability to transmit groundwater (i.e., nature of their porosity and permeability), which at the NTS is mainly a function of the rock’s primary lithology, type and degree of postdepositional alteration, and propensity to fracture. The second, or highest, level within the UGTA CAU-scale hydrostratigraphic system is the HSU, which is the fundamental mapping/modeling unit within UGTA CAU-scale HFMs. HSUs are 3-D bodies that are represented in the finite element mesh for the UGTA groundwater modeling process. HSUs are defined systematically by stratigraphically organizing HGUs of similar character into larger HSUs designations. The careful integration of stratigraphic information in the development of HSUs is important to assure individual HSUs are internally consistent, correlatable, and mappable throughout all the model areas.

Lance Prothro, Sigmund Drellack Jr., Jennifer Mercadante

2009-01-31T23:59:59.000Z

323

Life cycle evolution and systematics of Campanulariid hydrozoans  

E-Print Network (OSTI)

The purpose of this thesis is to study campanulariid life cycle evolution and systematics. The Campanulariidae is a hydrozoan family with many life cycle variations, and provide an excellent model system to study life cycle ...

Govindarajan, Annette Frese, 1970-

2004-01-01T23:59:59.000Z

324

High-Order Generalized Lorenz N-Cycle Schemes for Semi-Lagrangian Models Employing Second Derivatives in Time  

Science Conference Proceedings (OSTI)

Having recently demonstrated that significant enhancement of forecast accuracy in a semi-Lagrangian model results from the application of high-order time integration methods to the second-derivative form of the equations governing the ...

R. J. Purser; L. M. Leslie

1997-06-01T23:59:59.000Z

325

The Seasonal Cycle of Meridional Heat Transport in a Numerical Model of the Pacific Equatorial Upwelling Zone  

Science Conference Proceedings (OSTI)

The seasonal heat transport mechanisms important in the Pacific equatorial upwelling zone are investigated using the primitive equation, reduced gravity model developed by Gent and Cane. Mechanisms of meridional heat transport are shown and ...

Esther C. Brady; Peter R. Gent

1994-12-01T23:59:59.000Z

326

The HAMMONIA Chemistry Climate Model: Sensitivity of the Mesopause Region to the 11-Year Solar Cycle and CO2 Doubling  

Science Conference Proceedings (OSTI)

This paper introduces the three-dimensional Hamburg Model of the Neutral and Ionized Atmosphere (HAMMONIA), which treats atmospheric dynamics, radiation, and chemistry interactively for the height range from the earth’s surface to the ...

H. Schmidt; G. P. Brasseur; M. Charron; E. Manzini; M. A. Giorgetta; T. Diehl; V. I. Fomichev; D. Kinnison; D. Marsh; S. Walters

2006-08-01T23:59:59.000Z

327

Fuel Cycle CrossCut Group  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CrossCut Group CrossCut Group 1 NERAC Briefing: Assessment of Dose of Closed vs Open Gen-IV Fuel Cycles David Wade NERAC Meeting September 30, 2002 Fuel Cycle CrossCut Group 2 Public Dose and Worker Dose Comparison of Open vs Closed Fuel Cycles * Gen-IV fuel cycle options are meant to address all stated Gen-IV Goals - Dose to workers and to the public is one of the numerous elements to be evaluated by Gen-IV R&D - The Fuel Cycle Crosscut Group was assigned to take an early look at dose implication tradeoffs of open and closed fuel cycles * FCCG Interpretation of Assignment: - Collect already-existing evaluations and prepare a briefing on what is currently known Fuel Cycle CrossCut Group 3 Approach * Look at Actual Historical Doses Based on Operational Experience - Data compiled by the United Nations Scientific Committee on the Effects of Atomic

328

unit process | OpenEI  

Open Energy Info (EERE)

unit process unit process Dataset Summary Description Datasets are for the US electricity grid system interconnect regions (ASCC, FRCC, HICC, MRO, NPCC, RFC, SERC, SPP, TRE, WECC) for 2008. The data is provided in life cycle inventory (LCI) forms (both xls and xml). A module report and a detailed spreadsheet are also included. Source US Life Cycle Inventory Database Date Released May 01st, 2011 (3 years ago) Date Updated Unknown Keywords ASCC FRCC HICC interconnect region LCI life cycle inventory MRO NPCC RFC SERC SPP TRE unit process US utilities WECC Data application/zip icon interconnect_lci_datasets_2008.zip (zip, 6.3 MiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period License License Open Data Commons Public Domain Dedication and Licence (PDDL)

329

A Real-Time Gridded Crop Model for Assessing Spatial Drought Stress on Crops in the Southeastern United States  

Science Conference Proceedings (OSTI)

The severity of drought has many implications for society. Its impacts on rain-fed agriculture are especially direct, however. The southeastern United States, with substantial rain-fed agriculture and large variability in growing-season ...

Richard T. McNider; John R. Christy; Don Moss; Kevin Doty; Cameron Handyside; Ashutosh Limaye; Axel Garcia y Garcia; Gerrit Hoogenboom

2011-07-01T23:59:59.000Z

330

Development of a Laboratory Verified Single-Duct VAV System Model with Fan Powered Terminal Units Optimized Using Computational Fluid Dynamics  

E-Print Network (OSTI)

Single Duct Variable Air Volume (SDVAV) systems use series and parallel Fan Powered Terminal Units to control the air flow in conditioned spaces. This research developed a laboratory verified model of SDVAV systems that used series and parallel fan terminal units where the fan speeds were controlled by either Silicon Controlled Rectifiers (SCR) or Electronically Commutated Motors (ECM) motors. As part of the research, the model was used to compare the performance of the systems and to predict the harmonics generated by ECM systems. All research objectives were achieved. The CFD model, which was verified with laboratory measurements, showed the potential to identify opportunities for improvement in the design of the FPTU and accurately predicted the static pressure drop as air passed through the unit over the full operating range of the FPTU. Computational fluid dynamics (CFD) models of typical a FPTU were developed and used to investigate opportunities for optimizing the design of FPTUs. The CFD model identified key parameters required to conduct numerical simulations of FPTU and some of the internal components used to manufacture the units. One key internal component was a porous baffle used to enhance mixing when primary air and induced air entered the mixing chamber. The CFD analysis showed that a pressure-drop based on face velocity model could be used to accurately predict the performance of the FPTU. The SDVAV simulation results showed that parallel FPTUs used less energy overall than series systems that used SCR motors as long as primary air leakage was not considered. Simulation results also showed that series ECM FPTUs used about the same amount of energy, within 3 percent, of parallel FPTU even when leakage was not considered. A leakage rate of 10 percent was enough to reduce the performance of the parallel FPTU to the level of the series SCR system and the series ECM FPTUs outperformed the parallel FPTUs at all weather locations used in the study.

Davis, Michael A.

2010-08-01T23:59:59.000Z

331

TRANSPORTATION SYSTEMS AND THE BUILT ENVIRONMENT:1 A LIFE-CYCLE ENERGY CASE STUDY AND ANALYSIS2  

E-Print Network (OSTI)

models for petroleum use (from driving) and26 residential and commercial power and natural gas use infrastructure) made up 44 to 47% of the life-cycle energy demands34 tallied. Energy elasticity calculations across the neighborhoods suggest that increased population35 density and reduced residential unit size

Kockelman, Kara M.

332

Mineral cycling in southeastern ecosystems. Proceedings of a symposium held at Augusta, Georgia May 1--3, 1974  

SciTech Connect

Sixty-six papers were presented on cycling of natural and man-made elements, including terrestrial, freshwater and marine environments, as well as current ideas on modeling. Principles governing elemental flow included radiocesium in natural environments, especially in the southeastern United States. Individual entries were made for 47 items.

Howell, F.G.; Gentry, J.B.; Smith, M.H. (eds.)

1975-01-01T23:59:59.000Z

333

Definition: Rankine cycle | Open Energy Information  

Open Energy Info (EERE)

Rankine cycle Rankine cycle Jump to: navigation, search Dictionary.png Rankine cycle Sometimes referred to as the steam cycle. Fuel is used to heat a liquid to produce a high pressure gas that expands and produces work, such as turning a turbine; when the turbine is connected to a generator, it produces electricity. Usually water is the liquid used in the Rankine cycle (to produce steam), but other liquids can also be used. The exhaust vapor expelled from the turbine condenses and the liquid is pumped back to the boiler to repeat the cycle.[1][2] View on Wikipedia Wikipedia Definition The Rankine cycle is a mathematical model that is used to predict the performance of steam engines. The Rankine cycle is an idealised thermodynamic cycle of a heat engine that converts heat into mechanical

334

Modeling Approach/Strategy for Corrective Action Unit 99: Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1, with ROTC-1  

Science Conference Proceedings (OSTI)

This document describes an approach for preliminary (Phase I) flow and transport modeling for the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU). This modeling will take place before the planned Phase II round of data collection to better identify the remaining data gaps before the fieldwork begins. Because of the geologic complexity, limited number of borings, and large vertical gradients, there is considerable uncertainty in the conceptual model for flow; thus different conceptual models will be evaluated, in addition to different framework and recharge models. The transport simulations will not be used to formally calculate the Contaminant Boundary at this time. The modeling (Phase II) will occur only after the available data are considered sufficient in scope and quality.

Greg Ruskauff

2008-06-01T23:59:59.000Z

335

Fuel-Cycle Assessment of Selected Bioethanol Production Pathways  

E-Print Network (OSTI)

Fuel-Cycle Assessment of Selected Bioethanol Production Pathways in the United States ANL/ESD/06-Cycle Assessment of Selected Bioethanol Production Pathways in the United States ANL/ESD/06-7 by M. Wu, M. Wang ................................................................................ 6 2 Simplified Process Flow Diagram of Biochemical Conversion of Corn Stover to Ethanol with Steam

Argonne National Laboratory

336

Advanced Fuel Cycle Economic Sensitivity Analysis  

Science Conference Proceedings (OSTI)

A fuel cycle economic analysis was performed on four fuel cycles to provide a baseline for initial cost comparison using the Gen IV Economic Modeling Work Group G4 ECON spreadsheet model, Decision Programming Language software, the 2006 Advanced Fuel Cycle Cost Basis report, industry cost data, international papers, the nuclear power related cost study from MIT, Harvard, and the University of Chicago. The analysis developed and compared the fuel cycle cost component of the total cost of energy for a wide range of fuel cycles including: once through, thermal with fast recycle, continuous fast recycle, and thermal recycle.

David Shropshire; Kent Williams; J.D. Smith; Brent Boore

2006-12-01T23:59:59.000Z

337

Correlation between Median Household Income and LEED Sustainable Site Criteria for Public Transportation Access and a Regression Model Predicting Appraised Unit Value of Unimproved Parcels in Houston, Texas  

E-Print Network (OSTI)

The Leadership in Energy and Environmental Design (LEED) Green Building Rating System provides third-party verification for environmentally sustainable construction. LEED certified buildings often provide healthier work and living environments, however, it does not provide any direct economic incentives to the owners and developers. An early research suggested that there was a significant correlation between appraised unit value of a parcel and LEED sustainable site criteria for public transportation access. Moreover, the regression model for predicting appraised unit value of a parcel suggested that the coefficient of Number of Light Rail Stations was positive, while the coefficient of Number of Bus Stops was negative. This result contradicted our original expectation that both number of bus stops and light rail stations could have a positive effect on the appraised unit value. Hence it becomes important to conduct further research to explain this phenomenon. In this research, Pearson correlation was examined to determine whether there is a significant correlation between median household income and the number of bus stops and light rail stations for a given parcel that meet LEED sustainable site criteria for public transportation access. After confirming no significant correlation exists, multiple regression analysis was applied to establish a regression model for predicting unit value of a given parcel using number of bus stops and light rail stations for a given parcel that meet LEED sustainable site criteria for public transportation access, median household income and parcel area as the independent variables. Result of Pearson correlation indicated that there was no significant correlation exists between median household income and the number of bus stops and light rail stations for a given parcel which met LEED sustainable site criteria for public transportation access. Findings of multiple regression analysis suggested that all independent variables were significant predictors for unit value of a parcel. Besides, this regression model had a higher adjusted R- square value than that of the model which was established by Bhagyashri Joshi. It means that this regression model could better predict appraised unit value of an unimproved parcel.

Ji, Qundi

2010-05-01T23:59:59.000Z

338

Cycling Operation of Fossil Plants: Volume 3: Cycling Evaluation of Pepco's Potomac River Generating Station  

Science Conference Proceedings (OSTI)

This report presents a methodology for examining the economic feasibility of converting fossil power plants from baseload to cycling service. It employs this approach to examine a proposed change of Pepco's Potomac River units 3, 4, and 5 from baseload operation to two-shift cycling.

1991-06-01T23:59:59.000Z

339

Pre-Combustion CO2 Removal System ? Demonstration Unit  

NLE Websites -- All DOE Office Websites (Extended Search)

Budget Period 2 * Long-term Sorbent Cycling * Design of a Breadboard Prototype Test Unit * High Fidelity Process Optimization and Design Budget Period 3 * Fabrication of the...

340

Comparisons of four categories of waste recycling in China's paper industry based on physical input-output life-cycle assessment model  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Using crop straws and wood wastes for paper production should be promoted. Black-Right-Pointing-Pointer Bagasse and textile waste recycling should be properly limited. Black-Right-Pointing-Pointer Imports of scrap paper should be encouraged. Black-Right-Pointing-Pointer Sensitivity analysis, uncertainties and policy implications are discussed. - Abstract: Waste recycling for paper production is an important component of waste management. This study constructs a physical input-output life-cycle assessment (PIO-LCA) model. The PIO-LCA model is used to investigate environmental impacts of four categories of waste recycling in China's paper industry: crop straws, bagasse, textile wastes and scrap paper. Crop straw recycling and wood utilization for paper production have small total intensity of environmental impacts. Moreover, environmental impacts reduction of crop straw recycling and wood utilization benefits the most from technology development. Thus, using crop straws and wood (including wood wastes) for paper production should be promoted. Technology development has small effects on environmental impacts reduction of bagasse recycling, textile waste recycling and scrap paper recycling. In addition, bagasse recycling and textile waste recycling have big total intensity of environmental impacts. Thus, the development of bagasse recycling and textile waste recycling should be properly limited. Other pathways for reusing bagasse and textile wastes should be explored and evaluated. Moreover, imports of scrap paper should be encouraged to reduce large indirect impacts of scrap paper recycling on domestic environment.

Liang Sai [School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); Zhang, Tianzhu, E-mail: zhangtz@mail.tsinghua.edu.cn [School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); Xu Yijian [School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084 (China); China Academy of Urban Planning and Design, Beijing 100037 (China)

2012-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Metric Units  

Science Conference Proceedings (OSTI)

... A, B, C, D, E, F, G, H, I, J. 1, Steam Point Calculator: Metric Units, Elevation Converter, ... 6, Height of steam point apparatus above ground (m), 0, m, ...

2011-12-22T23:59:59.000Z

342

United States  

Office of Legacy Management (LM)

- I - I United States Department of Energy D lSCk Al M E R "This book was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency

343

AN ESSENTIAL INDUSTRY AT THE CROSSROADS: DEREGULATION, RESTRUCTURING, AND A NEW MODEL FOR THE UNITED STATES ’ BULK POWER SYSTEM  

E-Print Network (OSTI)

All materials contained within this document are protected by United States copyright law and may not be reproduced, distributed, transmitted, displayed, published or broadcast without the prior written permission of the author. You may not alter or remove any trademark, copyright or other notice from copies of the content. You may download this material, after contacting the author, for your personal, noncommercial use only. For questions, further information or comments, please send to:

Copyright Jeffrey; Thomas Hein; All Rights Reserved; Mr. Jeffrey T. Hein (jeff; Jeffrey Thomas Hein

2003-01-01T23:59:59.000Z

344

Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, Rev. No.: 0  

SciTech Connect

The Phase II Frenchman Flat groundwater flow model is a key element in the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996) corrective action strategy for the Underground Test Area (UGTA) Frenchman Flat corrective action unit (CAU). The objective of this integrated process is to provide an estimate of the vertical and horizontal extent of contaminant migration for each CAU to predict contaminant boundaries. A contaminant boundary is the model-predicted perimeter that defines the extent of radionuclide-contaminated groundwater from underground testing above background conditions exceeding the ''Safe Drinking Water Act'' (SDWA) standards. The contaminant boundary will be composed of both a perimeter boundary and a lower hydrostratigraphic unit (HSU) boundary. The computer model will predict the location of this boundary within 1,000 years and must do so at a 95 percent level of confidence. Additional results showing contaminant concentrations and the location of the contaminant boundary at selected times will also be presented. These times may include the verification period, the end of the five-year proof-of-concept period, as well as other times that are of specific interest. This report documents the development and implementation of the groundwater flow model for the Frenchman Flat CAU. Specific objectives of the Phase II Frenchman Flat flow model are to: (1) Incorporate pertinent information and lessons learned from the Phase I Frenchman Flat CAU models. (2) Develop a three-dimensional (3-D), mathematical flow model that incorporates the important physical features of the flow system and honors CAU-specific data and information. (3) Simulate the steady-state groundwater flow system to determine the direction and magnitude of groundwater fluxes based on calibration to Frenchman Flat hydrogeologic data. (4) Quantify the uncertainty in the direction and magnitude of groundwater flow due to uncertainty in parameter values and alternative component conceptual models (e.g., geology, boundary flux, and recharge).

John McCord

2006-05-01T23:59:59.000Z

345

Terrestrial Carbon Cycle Dynamics under Recent and Future Climate Change  

Science Conference Proceedings (OSTI)

The behavior of the terrestrial carbon cycle under historical and future climate change is examined using the University of Victoria Earth System Climate Model, now coupled to a dynamic terrestrial vegetation and global carbon cycle model. When ...

H. Damon Matthews; Andrew J. Weaver; Katrin J. Meissner

2005-05-01T23:59:59.000Z

346

Implementation of a Two-Way Interactive Atmospheric and Ecological Model and Its Application to the Central United States  

Science Conference Proceedings (OSTI)

A coupled Regional Atmospheric Modeling System (RAMS) and ecosystem (CENTURY) modeling system has been developed to study regional-scale two-way interactions between the atmosphere and biosphere. Both atmospheric forcings and ecological ...

Lixin Lu; Roger A. Pielke Sr.; Glen E. Liston; William J. Parton; Dennis Ojima; Melannie Hartman

2001-03-01T23:59:59.000Z

347

Characteristics of High-Resolution Versions of the Met Office Unified Model for Forecasting Convection over the United Kingdom  

Science Conference Proceedings (OSTI)

With many operational centers moving toward order 1-km-gridlength models for routine weather forecasting, this paper presents a systematic investigation of the properties of high-resolution versions of the Met Office Unified Model for short-range ...

Humphrey W. Lean; Peter A. Clark; Mark Dixon; Nigel M. Roberts; Anna Fitch; Richard Forbes; Carol Halliwell

2008-09-01T23:59:59.000Z

348

Simulation of annual biogeochemical cycles of nutrient balance, phytoplankton bloom(s), and DO in Puget Sound using an unstructured grid model  

Science Conference Proceedings (OSTI)

Nutrient pollution from rivers, nonpoint source runoff, and nearly 100 wastewater discharges is a potential threat to the ecological health of Puget Sound with evidence of hypoxia in some basins. However, the relative contributions of loads entering Puget Sound from natural and anthropogenic sources, and the effects of exchange flow from the Pacific Ocean are not well understood. Development of a quantitative model of Puget Sound is thus presented to help improve our understanding of the annual biogeochemical cycles in this system using the unstructured grid Finite Volume Coastal Ocean Model (FVCOM) framework and the Integrated Compartment Model (CE QUAL-ICM) water quality kinetics. Results based on 2006 data show that phytoplankton growth and die-off, succession between two species of algae, nutrient dynamics, and dissolved oxygen in Puget Sound are strongly tied to seasonal variation of temperature, solar radiation, and the annual exchange and flushing induced by upwelled Pacific Ocean waters. Concentrations in the mixed outflow surface layer occupying approximately 5?20 m of the upper water column show strong effects of eutrophication from natural and anthropogenic sources, spring and summer algae blooms, accompanied by depleted nutrients but high dissolved oxygen levels. The bottom layer reflects dissolved oxygen and nutrient concentrations of upwelled Pacific Ocean water modulated by mixing with biologically active surface outflow in the Strait of Juan De Fuca prior to entering Puget Sound over the Admiralty Inlet. The effect of reflux mixing at the Admiralty Inlet sill resulting in lower nutrient and higher dissolved oxygen levels in bottom waters of Puget Sound than the incoming upwelled Pacific Ocean water is reproduced. By late winter, with the reduction in algal activity, water column constituents of interest, were renewed and the system appeared to reset with cooler temperature, higher nutrient, and higher dissolved oxygen waters from the Pacific Ocean.

Khangaonkar, Tarang; Sackmann, Brandon S.; Long, Wen; Mohamedali, Teizeen; Roberts, Mindy

2012-08-14T23:59:59.000Z

349

Proceedings: Ninth International Conference on Cycle Chemistry in Fossil and Combined Cycle Plants with Heat Recovery Steam Generators  

Science Conference Proceedings (OSTI)

Proper selection, application, and optimization of cycle chemistry have long been recognized as integral to ensuring the highest possible levels of component availability and reliability in fossil-fired generating plant units. These proceedings of the Ninth EPRI International Conference on Cycle Chemistry in Fossil Plants address state-of-the-art practices in conventional and combined-cycle plants. The content provides a worldwide perspective on cycle chemistry practices and insight on industry issues an...

2010-01-22T23:59:59.000Z

350

High Cycle Fatigue in a Single Crystal Superalloy: Time ...  

Science Conference Proceedings (OSTI)

Keywords: Single crystal superalloys, High cycle fatigue, Environmental coatings, Rupture ... modes were modeled separately and then combined into a damage.

351

Nuclear Fuel Cycle Cost Comparison Between Once-Through and Fully Closed Cycles  

Science Conference Proceedings (OSTI)

This report presents results from a parametric study of equilibrium fuel cycle costs for a closed fuel cycle with multi-recycling of plutonium (Pu) and minor actinides in fast reactors (FRs) compared to an open, once-through fuel cycle using pressurized water reactors (PWRs). The study examines the impact on fuel cycle costs from changes in the unit costs of uranium, advanced plutonium and uranium recovery by extraction (PUREX) reprocessing of discharged fast-reactor mixed-oxide (FR-MOX) fuel, and fabric...

2010-11-04T23:59:59.000Z

352

Life Cycle Engineering Group  

Science Conference Proceedings (OSTI)

... for green manufacturing and construction applications; conduct life cycle engineering assessments for energy efficiency and environmental ...

2012-08-23T23:59:59.000Z

353

HUMID AIR TURBINE CYCLE TECHNOLOGY DEVELOPMENT PROGRAM  

SciTech Connect

The Humid Air Turbine (HAT) Cycle Technology Development Program focused on obtaining HAT cycle combustor technology that will be the foundation of future products. The work carried out under the auspices of the HAT Program built on the extensive low emissions stationary gas turbine work performed in the past by Pratt & Whitney (P&W). This Program is an integral part of technology base development within the Advanced Turbine Systems Program at the Department of Energy (DOE) and its experiments stretched over 5 years. The goal of the project was to fill in technological data gaps in the development of the HAT cycle and identify a combustor configuration that would efficiently burn high moisture, high-pressure gaseous fuels with low emissions. The major emphasis will be on the development of kinetic data, computer modeling, and evaluations of combustor configurations. The Program commenced during the 4th Quarter of 1996 and closed in the 4th Quarter of 2001. It teamed the National Energy Technology Laboratory (NETL) with P&W, the United Technologies Research Center (UTRC), and a subcontractor on-site at UTRC, kraftWork Systems Inc. The execution of the program started with bench-top experiments that were conducted at UTRC for extending kinetic mechanisms to HAT cycle temperature, pressure, and moisture conditions. The fundamental data generated in the bench-top experiments was incorporated into the analytical tools available at P&W to design the fuel injectors and combustors. The NETL then used the hardware to conduct combustion rig experiments to evaluate the performance of the combustion systems at elevated pressure and temperature conditions representative of the HAT cycle. The results were integrated into systems analysis done by kraftWork to verify that sufficient understanding of the technology had been achieved and that large-scale technological application and demonstration could be undertaken as follow-on activity. An optional program extended the experimental combustion evaluations to several specific technologies that can be used with HAT technology. After 5 years of extensive research and development, P&W is pleased to report that the HAT Technology Development Program goals have been achieved. With 0 to 10 percent steam addition, emissions achieved during this program featured less than 8 ppm NO{sub x}, less than 16 ppm CO, and unburned hydrocarbons corrected to 15 percent O{sub 2} for an FT8 engine operating between 0 and 120 F with 65 to 100 percent power at any day.

Richard Tuthill

2002-07-18T23:59:59.000Z

354

The Impact of GEM and MM5 Modeled Meteorological Conditions on CMAQ Air Quality Modeling Results in Eastern Canada and the Northeastern United States  

Science Conference Proceedings (OSTI)

The fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) is currently the meteorological model most widely used as input into the Community Multiscale Air Quality (CMAQ) modeling system. In ...

Steven C. Smyth; Dazhong Yin; Helmut Roth; Weimin Jiang; Michael D. Moran; Louis-Philippe Crevier

2006-11-01T23:59:59.000Z

355

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

BP Energy Company BP Energy Company OE Docket No. EA- 3 14 Order Authorizing Electricity Exports to Mexico Order No. EA-3 14 February 22,2007 BP Energy Company Order No. EA-314 I. BACKGROUND Exports of electricity from the United States to a foreign country are regulated by the Department of Energy (DOE) pursuant to sections 301(b) and 402(Q of the Department of Energy Organization Act (42 U.S.C. 7 15 l(b), 7172(f)) and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C.S24a(e)) . On May 22,2006, BP Energy Company (BP Energy) applied to DOE for an authorization to transmit electric energy from the United States to Mexico as a power marketer. BP Energy proposes to purchase surplus electric energy from electric utilities and other suppliers within the United States and to export that energy to ~Mexico. The cnergy

356

United States  

Office of Legacy Management (LM)

Office of Research and EPA 600/R-941209 Environmental Protection Development January 1993 Agency Washington, DC 20460 Offsite Environmental 57,,7 Monitoring Report Radiation Monitoring Around United States Nuclear Test Areas, Calendar Year 1992 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY OFFICE OF RESEARCH AND DEVELOPMENT ENVIRONMENTAL MONITORING SYSTEMS LABORATORY-LAS VEGAS P.O. BOX 93478 LAS VEGAS. NEVADA 891 93-3478 702/798-2100 Dear Reader: Since 1954, the U.S. Environmental Protection Agency (EPA) and its predecessor the U.S, Public Health Service (PHs) has conducted radiological monitoring in the offsite areas around United States nuclear test areas. The primary objective of this monitoring has been the protection of the health and safety of

357

Binary Cycle Power Plant | Open Energy Information  

Open Energy Info (EERE)

Binary Cycle Power Plant Binary Cycle Power Plant (Redirected from Binary Cycle Power Plants) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Binary Cycle Power Plant General List of Binary Plants Binary power plant process diagram - DOE EERE 2012 Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units. Low to moderately heated (below 400°F) geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point that water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines and subsequently, the generators.

358

Binary Cycle Power Plant | Open Energy Information  

Open Energy Info (EERE)

Binary Cycle Power Plant Binary Cycle Power Plant (Redirected from Binary) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Binary Cycle Power Plant General List of Binary Plants Binary power plant process diagram - DOE EERE 2012 Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units. Low to moderately heated (below 400°F) geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point that water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines and subsequently, the generators. Binary cycle power plants are closed-loop systems and virtually nothing

359

Teaching HS computer science as if the rest of the world existed: rationale for a HS Pre-APCS curriculum of interdisciplinary central-problem-based units that model real-world applications  

Science Conference Proceedings (OSTI)

The presentation, an interim report, will focus on the design, implementation and rationale for a pre-APCS HS curriculum of Interdisciplinary Central-Problem-Based units that model real-world applications. In a typical multi-week unit, students use an ... Keywords: K-12 instruction, Pre-APCS, central problem, curriculum, gender / diversity, increasing enrollment, interdisciplinary

Scott R. Portnoff

2012-02-01T23:59:59.000Z

360

Comprehensive Energy Assessment: EE and RE Project Optimization Modeling for United States Pacific Command (USPACOM) American Recovery and Reinvestment Act (ARRA) FEMP Technical Assistance  

SciTech Connect

This report summarizes a study and corresponding model development conducted in support of the United States Pacific Command (USPACOM) as part of the Federal Energy Management Program (FEMP) American Reinvestment and Recovery Act (ARRA). This research was aimed at developing a mathematical programming framework and accompanying optimization methodology in order to simultaneously evaluate energy efficiency (EE) and renewable energy (RE) opportunities. Once developed, this research then demonstrated this methodology at a USPACOM installation - Camp H.M. Smith, Hawaii. We believe this is the first time such an integrated, joint EE and RE optimization methodology has been constructed and demonstrated.

Brigantic, Robert T.; Papatyi, Anthony F.; Perkins, Casey J.

2010-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Fuel Cycle Research & Development Documents | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Initiatives » Fuel Cycle Technologies » Fuel Cycle Research & Initiatives » Fuel Cycle Technologies » Fuel Cycle Research & Development » Fuel Cycle Research & Development Documents Fuel Cycle Research & Development Documents November 8, 2011 2011 Fuel Cycle Technologies Annual Review Meeting As the largest domestic source of low-carbon energy, nuclear power is making major contributions toward meeting our nation's current and future energy demands. The United States must continue to ensure improvements and access to this technology so we can meet our economic, environmental and energy security goals. We rely on nuclear energy because it provides a consistent, reliable and stable source of base load electricity with an excellent safety record in the United States. July 11, 2011 Nuclear Separations Technologies Workshop Report

362

OSPREY Model  

SciTech Connect

The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed within Multi-physics Object Oriented Simulation Environment (MOOSE) developed at the Idaho National Laboratory (INL). Off-gas Separation and REcoverY (OSPREY) models the adsorption of off-gas constituents for dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions. Inputs to the model include gas, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. The simulation outputs component concentrations along the column length as a function of time from which breakthrough data is obtained. The breakthrough data can be used to determine bed capacity, which in turn can be used to size columns. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data and parameters were input into the adsorption model to develop models specific for krypton adsorption. The same can be done for iodine, xenon, and tritium. The model will be validated with experimental breakthrough curves. Customers will be given access to OSPREY to used and evaluate the model.

Veronica J. Rutledge

2013-01-01T23:59:59.000Z

363

Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Update 1 to: A Dispersion Modeling Analysis of Downwash from Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant, Modeling Unit 1 Emissions in a Cycling Mode Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Power Plant, Modeling Unit 1 Emissions in a Cycling Mode Docket No. EO-05-01. This report describes dispersion modeling performed for Unit 1 at Mirant's Potomac River Generating Station. The modeling was performed according to the Protocol approved by the Virginia Department of Environmental Quality. The purpose of the modeling was to demonstrate that Unit 1 operating alone under specific loads and during certain periods in a calendar day will not cause or contribute to exceedances of the National Ambient Air Quality Standards (NAAQS).

364

High-Resolution Spatial Modeling of Daily Weather Elements for a Catchment in the Oregon Cascade Mountains, United States  

Science Conference Proceedings (OSTI)

High-quality, daily meteorological data at high spatial resolution are essential for a variety of hydrologic and ecological modeling applications that support environmental risk assessments and decision making. This paper describes the ...

Christopher Daly; Jonathan W. Smith; Joseph I. Smith; Robert B. McKane

2007-10-01T23:59:59.000Z

365

Comparison of Model Forecast Skill of Sea Level Pressure along the East and West Coasts of the United States  

Science Conference Proceedings (OSTI)

Despite recent advances in numerical weather prediction, major errors in short-range forecasts still occur. To gain insight into the origin and nature of model forecast errors, error frequencies and magnitudes need to be documented for different ...

Garrett B. Wedam; Lynn A. McMurdie; Clifford F. Mass

2009-06-01T23:59:59.000Z

366

Renewable Energy Cost Modeling: A Toolkit for Establishing Cost-Based Incentives in the United States; March 2010 -- March 2011  

Science Conference Proceedings (OSTI)

This report is intended to serve as a resource for policymakers who wish to learn more about establishing cost-based incentives. The report will identify key renewable energy cost modeling options, highlight the policy implications of choosing one approach over the other, and present recommendations on the optimal characteristics of a model to calculate rates for cost-based incentives, feed-in tariffs (FITs), or similar policies. These recommendations will be utilized in designing the Cost of Renewable Energy Spreadsheet Tool (CREST). Three CREST models will be publicly available and capable of analyzing the cost of energy associated with solar, wind, and geothermal electricity generators. The CREST models will be developed for use by state policymakers, regulators, utilities, developers, and other stakeholders to assist them in current and future rate-setting processes for both FIT and other renewable energy incentive payment structures and policy analyses.

Gifford, J. S.; Grace, R. C.; Rickerson, W. H.

2011-05-01T23:59:59.000Z

367

Hydrological Processes in Regional Climate Model Simulations of the Central United States Flood of June–July 1993  

Science Conference Proceedings (OSTI)

Thirteen regional climate model (RCM) simulations of June–July 1993 were compared with each other and observations. Water vapor conservation and precipitation characteristics in each RCM were examined for a 10° × 10° subregion of the upper ...

Christopher J. Anderson; Raymond W. Arritt; Zaitao Pan; Eugene S. Takle; William J. Gutowski Jr.; Francis O. Otieno; Renato da Silva; Daniel Caya; Jens H. Christensen; Daniel Lüthi; Miguel A. Gaertner; Clemente Gallardo; Filippo Giorgi; René Laprise; Song-You Hong; Colin Jones; H-M. H. Juang; J. J. Katzfey; John L. McGregor; William M. Lapenta; Jay W. Larson; John A. Taylor; Glen E. Liston; Roger A. Pielke Sr.; John O. Roads

2003-06-01T23:59:59.000Z

368

NAM Model Forecasts of Warm-Season Quasi-Stationary Frontal Environments in the Central United States  

Science Conference Proceedings (OSTI)

Using a composite procedure, North American Mesoscale Model (NAM) forecast and observed environments associated with zonally oriented, quasi-stationary surface fronts for 64 cases during July–August 2006–08 were examined for a large region ...

Shih-Yu Wang; Adam J. Clark

2010-08-01T23:59:59.000Z

369

A Comparison of Three Canopy Interception Models for a Leafless Mixed Deciduous Forest Stand in the Eastern United States  

Science Conference Proceedings (OSTI)

Canopy interception of incident precipitation is a critical component of the forest water balance during each of the four seasons. Models have been developed to predict precipitation interception from standard meteorological variables because of ...

Nicholas P. Klingaman; Delphis F. Levia; Ethan E. Frost

2007-08-01T23:59:59.000Z

370

Evaluation of a Conjunctive Surface–Subsurface Process Model (CSSP) over the Contiguous United States at Regional–Local Scales  

Science Conference Proceedings (OSTI)

This study presents a comprehensive evaluation on a Conjunctive Surface–Subsurface Process Model (CSSP) in predicting soil temperature–moisture distributions, terrestrial hydrology variations, and land–atmosphere exchanges against various in situ ...

Xing Yuan; Xin-Zhong Liang

2011-08-01T23:59:59.000Z

371

Damage of Land Biosphere due to Intense Warming by 1000-Fold Rapid Increase in Atmospheric Methane: Estimation with a Climate–Carbon Cycle Model  

Science Conference Proceedings (OSTI)

Decadal-time-scale responses of climate and the global carbon cycle to warming associated with rapid increases in atmospheric methane from a massive methane release from marine sedimentary methane hydrates are investigated with a coupled climate–...

Atsushi Obata; Kiyotaka Shibata

2012-12-01T23:59:59.000Z

372

Green Building- Efficient Life Cycle  

E-Print Network (OSTI)

Energy saving does not just apply to traffic, production or agriculture. Buildings are also contributing to the climate change. The focus here is on the energy they use and on their CO2 emissions. Each year, Siemens invests more than two billion euros in the appropriate research and development. For customers, this means that Siemens is already providing them with energy efficient solutions that save resources and reduce emissions. Siemens Real Estate (SRE) has taken on the task of ensuring that Siemens AG will become 20 percent more energy efficient by 2011, and it has turned an efficiency program for existing real estate, which has been in existence since 2005, into an integrated green building initiative. This initiative comprises the components “Sustainable Building Design”, “Life Cycle Cost Analysis”, “Green Building Certification” and “Natural Resources Management”. These components are deliberately arranged around the life cycle of the real estate concerned. This allows a different emphasis to be placed on the different questions in each project phase and each phase of a building’s life and for them to be answered in a targeted manner. “Sustainable Building Design” comes into effect during the tasking and preliminary planning phase of a building project; and, by providing a specially developed sustainability manual, it helps with the definition of target values and the drawing up of efficiency strategies for the planning of the building. The manual epitomizes, and sets out clearly, the attitude of SRE to all building-specific sustainability matters. In addition, it is used in the offering of rewards for project competitions. As a result, through a selection of different energy-efficiency measures that have been roughly conceived beforehand, the primary energy consumption can already be restricted in the project definition phase. “Life Cycle Cost Analysis” comes into effect when the blueprint for buildings is being drawn up. Up to now, when components and systems were being chosen, the main focus was usually on the investment costs involved. By using a cost tool developed specifically to meet the needs of the company, SRE will in future be able to estimate the component-specific utilization costs – such as cleaning, maintenance, and the use of energy – at an early planning stage. “Green Building Certification” is used in building projects during the planning and implementation phase, and it thus ensures the quality of the new real estate over the long term. Siemens is implementing the Green Building Program of the European Commission in new building projects and renovation work in EU countries. In all other countries that are not taking part in the EU Green Building Program, SRE uses certification in accordance with LEED (Leadership in Energy and Environmental Design). In the LEED certification, a transparent and easy-to-use catalog of criteria is employed to make an assessment of the use of energy and other aspects of sustainability, such as the selection of the plot of land, the efficient use of water, the quality of air within buildings, and the selection of materials. This ensures that a neutral and independent assessment is made of all new building and large-scale renovation projects. The action program “Natural Resources Management” rounds off the range of measures in the area of existing real estate. The aim of the program is to identify and highlight all latent efficiency potential in existing buildings. This includes, for instance, modernizing the control equipment used for the heating and ventilation systems. This entails replacing electrical power units with more efficient models, and retrofitting fans and pumps with frequency converters. Sixty buildings have now been inspected, and savings of almost eight million Euros have been achieved. The average payback period is less than two years. One example of this is an old Siemens building from the 1970s at the Munich-Perlach site. Through energy optimization, it has been possible to cu

Kohns, R.

2008-10-01T23:59:59.000Z

373

Phase I Flow and Transport Model Document for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada National Security Site, Nye County, Nevada, Revision 1  

Science Conference Proceedings (OSTI)

The Underground Test Area (UGTA) Corrective Action Unit (CAU) 97, Yucca Flat/Climax Mine, in the northeast part of the Nevada National Security Site (NNSS) requires environmental corrective action activities to assess contamination resulting from underground nuclear testing. These activities are necessary to comply with the UGTA corrective action strategy (referred to as the UGTA strategy). The corrective action investigation phase of the UGTA strategy requires the development of groundwater flow and contaminant transport models whose purpose is to identify the lateral and vertical extent of contaminant migration over the next 1,000 years. In particular, the goal is to calculate the contaminant boundary, which is defined as a probabilistic model-forecast perimeter and a lower hydrostratigraphic unit (HSU) boundary that delineate the possible extent of radionuclide-contaminated groundwater from underground nuclear testing. Because of structural uncertainty in the contaminant boundary, a range of potential contaminant boundaries was forecast, resulting in an ensemble of contaminant boundaries. The contaminant boundary extent is determined by the volume of groundwater that has at least a 5 percent chance of exceeding the radiological standards of the Safe Drinking Water Act (SDWA) (CFR, 2012).

Andrews, Robert

2013-09-01T23:59:59.000Z

374

Current Projects for Reactor Physics and Fuel Cycle Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Systems Modeling and Design Analysis > Reactor Physics and Fuel Cycle Analysis > Current Projects Capabilities Nuclear Systems Modeling and Design Analysis Reactor Physics...

375

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

E-T Global Energy, LLC E-T Global Energy, LLC OE Docket No. EA-381 Order Authorizing Electricity Exports to Mexico Order No. EA-381 June 10, 2011 I. BACKGROUND E-T Global Energy, LLC Order No. EA-381 Exports of electricity from the United States to a foreign country are regulated by the Department of Energy (DOE) pursuant to sections 301(b) and 402(f) of the Department ofEnergy Organization Act (42 U.S.C. 7151(b), 7172(f)) and require authorization under section 202(e) ofthe Federal Power Act (FPA) (16 U.S.C.824a(e)) 1 * On May 10,2011, DOE received an application from E-T Global Energy, LLC (E-T Global) for authority to transmit electric energy from the United States to Mexico for five years as a power marketer using existing international transmission facilities. E-

376

United States  

Office of Legacy Management (LM)

WASHINGTON, TUESDAY, JUNE 28, 1983 @nngmeional Ruord United States of America .__ -- . . ,- PROCEEDINGS AND DEBATES OF THE 9@ CONGRESS, FIRST SESSION United States Government Printing Office SUPERINTENDENT OF DOCUMENTS Washmgton, D C 20402 OFFICIAL BUSINESS Penalty Ior pwate use. $xX Congresstonal Record (USPS 087-390) Postage and Fees Pad U S Government Prlnhng 0ffv.X 375 SECOND CLASS NEWSPAPER H.4578 ' C.QNGRESSIONAL RECORD - HOUSE June 28, 1983 H.J. Res. 273: Mr. BOUND. Mr. W~.XMAN. Mr. OBERSTAR, Mr. BEDELL. Mr. BONER of Tennessee, Mr. OWENS. Mr. DAUB, Mr. CONTE. Mr. RAHALL; Mr. GRAY, Mr. VANDER JACT. Mr. TRAKLER, and Mr. Vxrrro. H. Con. Res. 107: Mr. KASICH. Mr. AUCOIN. Mr. CARPER, and Mr. SIZHFIJER. H. Con. Res. 118: Mr. FISH. Mr. LANTOS.

377

United States  

Office of Legacy Management (LM)

ongrees;ional Record ongrees;ional Record United States of America __._ -.. I. :- PROCEEDINGS AND DEBATES OF THE 9tth CONGRESS, FIRST SESSION United States Government Printing Office SUPERINTENDENT OF DOCUMENTS Washmcqton. Cl C 20402 OFFICIAL BUSINESS Penalty Ior pwate use. $300 Congressmal Record (USPS 087-390) Postage and Fees Pad U S Governme3n:jPnntmg OfIce SECOND CLASS NEWSPAPER H.4578 ' June 28, 1983 -: I H.J. Res. 273: Mr. BOLAND, Mr. WA-. Mr. OBERSTAFC, M' r. BEDELL, Mr. BONER of Tennessee, Mr. OWENS. Mr. DAUB. Mr. CONTE. Mr. RAHALL,. Mr. GRAY, Mr. VANDER JAGT. Mr. TRAKLER. and Mr. VENTO. H. Con. Res. iO7: Mr. KASICH. Mr. ALCOIN. Mr. CARPER. and Mr. SCHEUER. H. Con. Res. 118: Mr. FISH, Mr. LANTOS. Mr. KILDEE. Mr. SOLARZ Mr. Bmrr, Mr. BELWLL, Mr. RANG~L, Mr. DYMALLY. Mr.

378

Cryogenic explosion environment modeling and testing of space shuttle and light-weight radioisotope heater unit interactions  

SciTech Connect

In order to assess the risk to the world's populace in the event of a Space Shuttle accident when radioisotope-containing heat sources are on board, testing of that system must be performed to determine release point, environments required, and the size distribution of the released fuel. To evaluate the performance of the Light-Weight Radioisotope Heater Unit (LWRHU) (101 of these 1-W items are placed on the Galileo spacecraft which will be launched from the Space Shuttle), some high-velocity impact and flyer plate testing was carried out. The results showed that a bare urania-fueled LWRHU clad (approximately 1-mm thick platinum-30 wt % rhodium alloy) will withstand 1100 m/s flyer plate (3.5-mm thick aluminum) impacts and 330 m/s impacts upon the Space Shuttle floor (approximately 12-mm thick aluminum) without rupture or fuel release. Velocities in the order of 600 m/s on a steel surface will cause clad failure with fuel release. The fuel breakup patterns were characterized as to quantity in a specific size range. These data were employed in the formal Safety Analysis Report for the LWRHU to support the planned 1986 Galileo launch. 19 figs.

Johnson, E.W.

1985-10-01T23:59:59.000Z

379

Variable Density Flow Modeling for Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States  

SciTech Connect

The Arches Province in the Midwestern U.S. has been identified as a major area for carbon dioxide (CO{sub 2}) storage applications because of the intersection of Mt. Simon sandstone reservoir thickness and permeability. To better understand large-scale CO{sub 2} storage infrastructure requirements in the Arches Province, variable density scoping level modeling was completed. Three main tasks were completed for the variable density modeling: Single-phase, variable density groundwater flow modeling; Scoping level multi-phase simulations; and Preliminary basin-scale multi-phase simulations. The variable density modeling task was successful in evaluating appropriate input data for the Arches Province numerical simulations. Data from the geocellular model developed earlier in the project were translated into preliminary numerical models. These models were calibrated to observed conditions in the Mt. Simon, suggesting a suitable geologic depiction of the system. The initial models were used to assess boundary conditions, calibrate to reservoir conditions, examine grid dimensions, evaluate upscaling items, and develop regional storage field scenarios. The task also provided practical information on items related to CO{sub 2} storage applications in the Arches Province such as pressure buildup estimates, well spacing limitations, and injection field arrangements. The Arches Simulation project is a three-year effort and part of the United States Department of Energy (U.S. DOE)/National Energy Technology Laboratory (NETL) program on innovative and advanced technologies and protocols for monitoring/verification/accounting (MVA), simulation, and risk assessment of CO{sub 2} sequestration in geologic formations. The overall objective of the project is to develop a simulation framework for regional geologic CO{sub 2} storage infrastructure along the Arches Province of the Midwestern U.S.

Joel Sminchak

2011-09-30T23:59:59.000Z

380

Comparison of Model Forecast Skill of Sea-Level Pressure Along the East and West Coasts of the United States  

E-Print Network (OSTI)

1 Comparison of Model Forecast Skill of Sea-Level Pressure Along the East and West Coasts, University of Washington, Seattle, Washington Submitted to: Weather and Forecasting May 2008 Revised recent advances in numerical weather prediction, major errors in short-range forecasts still occur

Mass, Clifford F.

Note: This page contains sample records for the topic "modeling cycling units" 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

Quantifying Carbon Cycle Feedbacks  

Science Conference Proceedings (OSTI)

Perturbations to the carbon cycle could constitute large feedbacks on future changes in atmospheric CO2 concentration and climate. This paper demonstrates how carbon cycle feedback can be expressed in formally similar ways to climate feedback, ...

J. M. Gregory; C. D. Jones; P. Cadule; P. Friedlingstein

2009-10-01T23:59:59.000Z

382

Weekly Precipitation Cycles along the Northeast Corridor?  

Science Conference Proceedings (OSTI)

Twenty years of precipitation data from seven cities along or near the east coast of the United States from the northern mid-Atlantic region to northern New England have been analyzed to determine if there are any weekly cycles in either daily ...

Mark P. DeLisi; Alan M. Cope; Jason K. Franklin

2001-06-01T23:59:59.000Z

383

Cycle to Cycle Manufacturing Process Control  

E-Print Network (OSTI)

Most manufacturing processes produce parts that can only be correctly measured after the process cycle has been completed. Even if in-process measurement and control is possible, it is often too expensive or complex to ...

Hardt, David E.

384

Metrics-Based Feedback Cycles for Software Life-Cycle Management and Process Improvement  

E-Print Network (OSTI)

This paper summarizes a global organizational feedback cycle, composed of four component feedback cycles, by which the COCOMO II cost estimation model [Boehm et al., 2000] can be used for (1) project or product line scoping; (2) project or product line management; (3) model recalibration to changing circumstances; and (4) evaluation project, product line, or organizational continuous process improvement initiatives

Barry Boehm

2000-01-01T23:59:59.000Z

385

Microsoft PowerPoint - Application of Stirling Cycle Generators...  

NLE Websites -- All DOE Office Websites (Extended Search)

VDC Pumping 24 VDC 460 A-Hr Battery Bank 24 VDC To 3 208 VAC Pumping Unit 24 208 y Inverter 24VDC VDC 208 VAC Stirling Cycle Heated Fuel Gas Umbilical 24VDC Rod Work Well...

386

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Wholesale Power Rate Schedule JW-1-J Availability: This rate schedule shall be available to public bodies and cooperatives served by the Progress Energy Florida and having points of delivery within 150 miles of the Jim Woodruff Project (hereinafter called the Project). Applicability: This rate schedule shall be applicable to firm power and accompanying energy made available by the Government from the Project and sold in wholesale quantities. Character of Service: The electric capacity and energy supplied hereunder will be three-phase alternating current at a nominal frequency of 60 cycles per second delivered at the delivery points of the customer. Monthly Rate: The monthly rate for capacity and energy made available or delivered under this

387

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5 5 United States Department of Energy Southeastern Power Administration Wholesale Power Rate Schedule CC-1-I Availability: This rate schedule shall be available to public bodies and cooperatives served through the facilities of Carolina Power & Light Company, Western Division (hereinafter called the Customers). Applicability: This rate schedule shall be applicable to electric capacity and energy available from the Dale Hollow, Center Hill, Wolf Creek, Cheatham, Old Hickory, Barkley, J. Percy Priest, and Cordell Hull Projects (all of such projects being hereinafter called collectively the "Cumberland Projects") and sold in wholesale quantities. Character of Service: The electric capacity and energy supplied hereunder will be three-phase alternating

388

Light-Weight Radioisotope Heater Unit final safety analysis report (LWRHU-FSAR): Volume 2: Accident Model Document (AMD)  

Science Conference Proceedings (OSTI)

The purpose of this volume of the LWRHU SAR, the Accident Model Document (AMD), are to: Identify all malfunctions, both singular and multiple, which can occur during the complete mission profile that could lead to release outside the clad of the radioisotopic material contained therein; Provide estimates of occurrence probabilities associated with these various accidents; Evaluate the response of the LWRHU (or its components) to the resultant accident environments; and Associate the potential event history with test data or analysis to determine the potential interaction of the released radionuclides with the biosphere.

Johnson, E.W.

1988-10-01T23:59:59.000Z

389

An Hourly Assimilation–Forecast Cycle: The RUC  

Science Conference Proceedings (OSTI)

The Rapid Update Cycle (RUC), an operational regional analysis–forecast system among the suite of models at the National Centers for Environmental Prediction (NCEP), is distinctive in two primary aspects: its hourly assimilation cycle and its use ...

Stanley G. Benjamin; Dezsö Dévényi; Stephen S. Weygandt; Kevin J. Brundage; John M. Brown; Georg A. Grell; Dongsoo Kim; Barry E. Schwartz; Tatiana G. Smirnova; Tracy Lorraine Smith; Geoffrey S. Manikin

2004-02-01T23:59:59.000Z

390

Transport of Passive Tracers in Baroclinic Wave Life Cycles  

Science Conference Proceedings (OSTI)

The transport of passive tracers in idealized baroclinic wave life cycles is studied using output from the National Center for Atmospheric Research Community Climate Model (CCM2). Two life cycles, LCn and LCs, are simulated, starting with ...

Elizabeth M. Stone; William J. Randel; John L. Stanford

1999-05-01T23:59:59.000Z

391

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Tenaslta Power Services Co. Tenaslta Power Services Co. OE Docket No. EA-243-A Order Authorizing Electricity Exports to Canada Order No. EA-243-A March 1,2007 Tenaska Power Services Co. Order No. EA-243-A I. BACKGROUND Exports of elcctricity from the United States to a foreign country are regulated by the Department of Energy (DOE) pursuant to sections 30 I(b) and 402(f) of the Departrncnt of' Energy Organizatio~l Act (42 U, S.C. 7 15 1 (b), 7 1 72Cf)) and rcquirc authorization under section 202(e) of the Federal Power Act (FPA) ( Z 6 U. s.c.824a(e)j1. On August 16,2001, DOE issued Order No. EA-243 authorizing Tenaska Power Scrvices Co. (Tenaska) to transmit electric cncrgy from the United States to Canada as a power marketer. That authority expired on August 16,2003. On August 14,2006, Teilaska applied to renew the electricity export authority

392

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

TexMex Energy, LLC TexMex Energy, LLC OE Docket No. EA-294-A Order Authorizing Electricity Exports to Mexico Order No. EA-294-A February 22, 2007 TexMex Energy, LLC Order No. EA-294-A I. BACKGROUND Exports of electricity from the United States to a foreign count~y are regulated by the Department of Energy (DOE) pursuant to sections 301(b) and 402(f) of the Department of Energy Organization Act (42 U.S.C. 7 15 1 (b), 71 72(f)) and require authorization under section 202(e) of the Federal Power Act (FPA) (16 U.S.C.824a(e)) . On August 25,2004, DOE issued Order No. EA-294 authorizing TexMex Energy LLC (TexMex) to transmit electric energy fiom the United States to Mexico as a power marketer. That authority expired on August 25, 2006. On September 8, 2006, TexMex applied to renew the electricity export authority

393

United States  

Gasoline and Diesel Fuel Update (EIA)

United States United States Coal ................................................ 4,367 4,077 4,747 4,181 4,473 4,125 4,983 4,330 4,414 4,003 4,796 4,178 4,344 4,479 4,348 Natural Gas .................................... 2,802 2,843 3,694 2,863 2,713 2,880 3,636 2,707 2,792 2,972 3,815 2,849 3,052 2,986 3,109 Petroleum (a) .................................. 74 73 81 67 73 70 75 66 75 70 76 66 74 71 71 Other Gases ................................... 32 33 36 32 32 34 37 33 33 35 39 34 33 34 35 Nuclear ........................................... 2,176 2,044 2,257 2,170 2,106 2,037 2,167 2,010 2,144 2,074 2,206 2,055 2,162 2,080 2,120 Renewable Energy Sources: Conventional Hydropower ........... 736 886 716 633 765 887 708 646 767 919 729 659 742 751 768 Wind ............................................ 491 520 353 449 477 521 379 475

394

Better Sensors and Controls for Cycling and Turndown  

Science Conference Proceedings (OSTI)

Changes in the electrical generation mix (increase in renewable energy supply), relative costs of fossil fuels, and evolution of the system demand have resulted in greater reliance on cycling and turndown operation in fossil power plants. Coal and combined-cycle generating units are experiencing a combination of broader operating conditions and aging sensing and control equipment, which results in operating limitations during cycling and turndown. This report summarizes sensing and control ...

2013-11-21T23:59:59.000Z

395

The High Cycle Fatigue and Final Fracture Behavior of Alloy Steel ...  

Science Conference Proceedings (OSTI)

Energy Based Fatigue Life Prediction Models and Methods for Combined Low Cycle and High Cycle Fatigue · Fatigue Behavior of AM60B Subjected to Variable  ...

396

A Hydrostratigraphic Framework Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Clark, Lincoln and Nye Counties, Nevada  

SciTech Connect

A new, revised three-dimensional (3-D) hydrostratigraphic framework model for Frenchman Flat was completed in 2004. The area of interest includes Frenchman Flat, a former nuclear testing area at the Nevada Test Site, and proximal areas. Internal and external reviews of an earlier (Phase I) Frenchman Flat model recommended additional data collection to address uncertainties. Subsequently, additional data were collected for this Phase II initiative, including five new drill holes and a 3-D seismic survey.

Bechtel Nevada

2005-09-01T23:59:59.000Z

397

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Bangor Hydro-Electric Company Bangor Hydro-Electric Company OE Docket No. PP-89-1 Amendment to Presidential Permit Order No. PP-89-1 December 30,2005 PRESIDENTIAL PERMIT AMENDMENT Bangor Hydro-Electric Company Order No. PP-89-1 I. BACKGROUND The Department of Energy (DOE) has responsibility for implementing Executive Order (E.O.) 10485, as amended by E.O. 12038, which requires the issuance of a Presidential permit by DOE before electric trans~nission facilities may be constructed, operated, maintained, or connected at the borders of the United States. DOE may issue such a permit if it determines that the permit is in the public interest and after obtaining favorable recommendations from the U.S. Departments of State and Defense. On December 16, 1988, Bangor Hydro-Electric Company (BHE) applied to DOE

398

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7 7 United States Department of Energy Southeastern Power Administration Wholesale Power Rate Schedule CTV-1-H Availability: This rate schedule shall be available to the Tennessee Valley Authority (hereinafter called TVA). Applicability: This rate schedule shall be applicable to electric capacity and energy generated at the Dale Hollow, Center Hill, Wolf Creek, Old Hickory, Cheatham, Barkley, J. Percy Priest, and Cordell Hull Projects (all of such projects being hereafter called collectively the "Cumberland Projects") and the Laurel Project sold under agreement between the Department of Energy and TVA. Character of Service: The electric capacity and energy supplied hereunder will be three-phase alternating current at a frequency of approximately 60 hertz at the outgoing terminals of the Cumberland

399

United States  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

United States Department of Energy Southeastern Power Administration Wholesale Power Rate Schedule CTVI-1-A Availability: This rate schedule shall be available to customers (hereinafter called the Customer) who are or were formerly in the Tennessee Valley Authority (hereinafter called TVA) service area. Applicability: This rate schedule shall be applicable to electric capacity and energy generated at the Dale Hollow, Center Hill, Wolf Creek, Old Hickory, Cheatham, Barkley, J. Percy Priest, and Cordell Hull Projects (all of such projects being hereafter called collectively the "Cumberland Projects") and the Laurel Project sold under agreement between the Department of Energy and the Customer. Character of Service: The electric capacity and energy supplied hereunder will be three-phase alternating

400

UNITED STATES  

Office of Legacy Management (LM)

f).~<~~ \--\c :y-,ai F p"- KG f).~<~~ \--\c :y-,ai F p"- KG WASHINOTDN 28.0. C. ' -lr ' \ ' ' --- ".I ?--" ' z I. .~;-4.' J frr*o& 2 ii, - - -4 70-147 LRL:JCD JAN !! 8 1958 Oregon Metallurgical Corporation P. 0. Box 484 Albany, Oregon Attention: Mr. Stephen M. Shelton General Manager Gentlemen: Enclosed is Special Nuclear Material License No. SNM-144, as amended. Very 33uly yours, r:; I,;, ll)~gQ""d".- Lyall Johnson Chief, Licensing Branch Division of Licensing & Regulation Enclosure: SNM-144, as amended Distribution: bRO0 Attn: Dr. H.M.Roth DFMusser NMM MMMann INS JCRyan FIN (2) HSteele LRL SRGustavson LRL Document room Formal file Suppl. file Br & Div rf's ' .b liwwArry s/VW- ' q+ ' yj/ 2; 2-' , COP' 1 J JAM01958 -- UNITED STATES ATOMIC ENERGY COMMISSION

Note: This page contains sample records for the topic "modeling cycling units" 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

Pipeline bottoming cycle study. Final report  

Science Conference Proceedings (OSTI)

The technical and economic feasibility of applying bottoming cycles to the prime movers that drive the compressors of natural gas pipelines was studied. These bottoming cycles convert some of the waste heat from the exhaust gas of the prime movers into shaft power and conserve gas. Three typical compressor station sites were selected, each on a different pipeline. Although the prime movers were different, they were similar enough in exhaust gas flow rate and temperature that a single bottoming cycle system could be designed, with some modifications, for all three sites. Preliminary design included selection of the bottoming cycle working fluid, optimization of the cycle, and design of the components, such as turbine, vapor generator and condensers. Installation drawings were made and hardware and installation costs were estimated. The results of the economic assessment of retrofitting bottoming cycle systems on the three selected sites indicated that profitability was strongly dependent upon the site-specific installation costs, how the energy was used and the yearly utilization of the apparatus. The study indicated that the bottoming cycles are a competitive investment alternative for certain applications for the pipeline industry. Bottoming cycles are technically feasible. It was concluded that proper design and operating practices would reduce the environmental and safety hazards to acceptable levels. The amount of gas that could be saved through the year 2000 by the adoption of bottoming cycles for two different supply projections was estimated as from 0.296 trillion ft/sup 3/ for a low supply projection to 0.734 trillion ft/sup 3/ for a high supply projection. The potential market for bottoming cycle equipment for the two supply projections varied from 170 to 500 units of varying size. Finally, a demonstration program plan was developed.

Not Available

1980-06-01T23:59:59.000Z

402

Life Cycles of Moist Baroclinic Eddies  

Science Conference Proceedings (OSTI)

The interaction between moisture and baroclinic eddies was examined through eddy life-cycle experiments using a global, primitive equation model. How condensation affects the structural evolution of eddies, their fluxes of heat, moisture, and ...

William J. Gutowski Jr.; Lee E. Branscome; Douglas A. Stewart

1992-02-01T23:59:59.000Z

403

Axisymmetric Inlet Design for Combined Cycle Engines.  

E-Print Network (OSTI)

??Performance considerations for a turbine-based combined-cycle engine inlet are presented using the inlet of the Lockheed SR-71 as a baseline. A numerical model is developed… (more)

Colville, Jesse

2005-01-01T23:59:59.000Z

404

Cycling Operation of Fossil-Fueled Plants: Volume 6: Evaluation and Strategy  

Science Conference Proceedings (OSTI)

This report, the sixth volume in a series (GS-7219), describes tools to help utilities define and evaluate strategies for cycling fossil-fueled power plants. To assist companies in their cycling decisions, the report describes far-reaching guidelines on cycling units, including economics, the effects on equipment life, and operations and maintenance. In developing a stepwise plant to cycling operation, EPRI investigators reviewed an extensive database of worldwide and U.S. experience with cycling. The re...

1993-10-01T23:59:59.000Z

405

Duty Cycle Software  

Duty cycles capture the influence of one variable in relations to the whole system. This allows for analysis in determining the impact of new ...

406

Nuclear fuel cycle costs  

Science Conference Proceedings (OSTI)

The costs for the back-end of the nuclear fuel cycle, which were developed as part of the Nonproliferation Alternative Systems Assessment Program (NASAP), are presented. Total fuel cycle costs are given for the pressurized water reactor once-through and fuel recycle systems, and for the liquid-metal fast breeder reactor system. These calculations show that fuel cycle costs are a small part of the total power costs. For breeder reactors, fuel cycle costs are about half that of the present once-through system. The total power cost of the breeder reactor system is greater than that of light-water reactor at today's prices for uranium and enrichment.

Burch, W.D.; Haire, M.J.; Rainey, R.H.

1982-02-01T23:59:59.000Z

407

Cycles in fossil diversity  

E-Print Network (OSTI)

Transitions in Global Marine Diversity, Science 281, 1157-know if this cycle is a variation in true diversity or onlyin observed diversity, but either case requires explanation

Rohde, Robert A.; Muller, Richard A.

2004-01-01T23:59:59.000Z

408

Elevated-Pressure Air Separation Unit...  

NLE Websites -- All DOE Office Websites (Extended Search)

3-8 (2013). Liese, E.A. and S.E. Zitney, "A Dynamic Process Model of a Natural Gas Combined Cycle - Model Development with Startup and Shutdown Simulations," Proc. of the...

409

Letter from Elizabeth Chimento and Poul Hertel, Sullivan Environmental Consultants Review of Mirant Unit 1 Plan  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Sent: Monday, December 19, 2005 11:56 AM To: Mansueti, Lawrence Subject: Sullivan Environmental Consultants Review of Mirant Unit 1 Plan Mr. Mansueti, Would you please enter the attached review of the Mirant Unit One Plan in your records for DOE Docket #EO-05-01? Sullivan Environmental Consultants completed this review which Poul Hertel and I commissioned re: ENSR Corp. "Update 1 to: A Dispersion Modeling Analysis of Downwash from Mirant's Potomac River Plant; Modeling Unit 1 Emissions in a Cycling Mode" (9/20/05). As of this date, we have received no response to the questions in the Sullivan analysis. We ask the Department of Energy to consider the issues raised in the Sullivan Review in deciding the plant's future operation.

410

FUEL CYCLE POTENTIAL WASTE FOR DISPOSITION  

SciTech Connect

The United States (U.S.) currently utilizes a once-through fuel cycle where used nuclear fuel (UNF) is stored on-site in either wet pools or in dry storage systems with ultimate disposal in a deep mined geologic repository envisioned. Within the Department of Energy's (DOE) Office of Nuclear Energy (DOE-NE), the Fuel Cycle Research and Development Program (FCR&D) develops options to the current commercial fuel cycle management strategy to enable the safe, secure, economic, and sustainable expansion of nuclear energy while minimizing proliferation risks by conducting research and development of advanced fuel cycles, including modified open and closed cycles. The safe management and disposition of used nuclear fuel and/or nuclear waste is a fundamental aspect of any nuclear fuel cycle. Yet, the routine disposal of used nuclear fuel and radioactive waste remains problematic. Advanced fuel cycles will generate different quantities and forms of waste than the current LWR fleet. This study analyzes the quantities and characteristics of potential waste forms including differing waste matrices, as a function of a variety of potential fuel cycle alternatives including: (1) Commercial UNF generated by uranium fuel light water reactors (LWR). Four once through fuel cycles analyzed in this study differ by varying the assumed expansion/contraction of nuclear power in the U.S; (2) Four alternative LWR used fuel recycling processes analyzed differ in the reprocessing method (aqueous vs. electro-chemical), complexity (Pu only or full transuranic (TRU) recovery) and waste forms generated; (3) Used Mixed Oxide (MOX) fuel derived from the recovered Pu utilizing a single reactor pass; and (4) Potential waste forms generated by the reprocessing of fuels derived from recovered TRU utilizing multiple reactor passes.

Jones, R.; Carter, J.

2010-10-13T23:59:59.000Z

411

FUEL CYCLE POTENTIAL WASTE FOR DISPOSITION  

SciTech Connect

The United States (U.S.) currently utilizes a once-through fuel cycle where used nuclear fuel (UNF) is stored on-site in either wet pools or in dry storage systems with ultimate disposal in a deep mined geologic repository envisioned. Within the Department of Energy's (DOE) Office of Nuclear Energy (DOE-NE), the Fuel Cycle Research and Development Program (FCR&D) develops options to the current commercial fuel cycle management strategy to enable the safe, secure, economic, and sustainable expansion of nuclear energy while minimizing proliferation risks by conducting research and development of advanced fuel cycles, including modified open and closed cycles. The safe management and disposition of used nuclear fuel and/or nuclear waste is a fundamental aspect of any nuclear fuel cycle. Yet, the routine disposal of used nuclear fuel and radioactive waste remains problematic. Advanced fuel cycles will generate different quantities and forms of waste than the current LWR fleet. This study analyzes the quantities and characteristics of potential waste forms including differing waste matrices, as a function of a variety of potential fuel cycle alternatives including: (1) Commercial UNF generated by uranium fuel light water reactors (LWR). Four once through fuel cycles analyzed in this study differ by varying the assumed expansion/contraction of nuclear power in the U.S. (2) Four alternative LWR used fuel recycling processes analyzed differ in the reprocessing method (aqueous vs. electro-chemical), complexity (Pu only or full transuranic (TRU) recovery) and waste forms generated. (3) Used Mixed Oxide (MOX) fuel derived from the recovered Pu utilizing a single reactor pass. (4) Potential waste forms generated by the reprocessing of fuels derived from recovered TRU utilizing multiple reactor passes.

Carter, J.

2011-01-03T23:59:59.000Z

412

RHESSys: Regional Hydro-Ecologic Simulation System—An Object-Oriented Approach to Spatially Distributed Modeling of Carbon, Water, and Nutrient Cycling  

Science Conference Proceedings (OSTI)

Process-based models that can represent multiple and interacting processes provide a framework for combining field-based measurements with evolving science-based models of specific hydroecological processes. Use of these models, however, requires ...

C. L. Tague; L. E. Band

2004-12-01T23:59:59.000Z

413

Power Plant Cycling Costs  

Science Conference Proceedings (OSTI)

This report provides a detailed review of the most up to date data available on power plant cycling costs. The primary objective of this report is to increase awareness of power plant cycling cost, the use of these costs in renewable integration studies and to stimulate debate between policymakers, system dispatchers, plant personnel and power utilities.

Kumar, N.; Besuner, P.; Lefton, S.; Agan, D.; Hilleman, D.

2012-07-01T23:59:59.000Z

414

Total energy cycle emissions and energy use of electric vehicles  

DOE Green Energy (OSTI)

The purpose of this project is to provide estimates of changes in life cycle energy use and emissions that would occur with the introduction of EVs. The topics covered include a synopsis of the methodology used in the project, stages in the EV and conventional vehicle energy cycles, characterization of EVs by type and driving cycle, load analysis and capacity of the electric utility, analysis of the materials used for vehicle and battery, description of the total energy cycle analysis model, energy cycle primary energy resource consumption, greenhouse gas emissions, energy cycle emissions, and conclusions.

Singh, M.

1997-12-31T23:59:59.000Z

415

NPP and the Global Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

the Global Carbon Cycle the Global Carbon Cycle Introduction Photosynthetic carbon fixation comprises a major component of the global carbon cycle. Data on net primary productivity (NPP) may be sparse, but a consistent NPP data set may be used to calibrate, parameterize and evaluate models of terrestrial carbon cycling, as well as for validation of remote sensing data and other applications (identifying trends, investigating biogeochemical processes, etc.). It is also useful to place such data within the context of carbon cycling and carbon storage worldwide. For example: How much carbon exists in the biosphere, and where exactly is it stored? How much is in fossil fuels (coal, oil, gas), and how large are current fossil-fuel emissions? How much is in living biomass (plants/ animals/ humans)?

416

Integrating Human Indoor Air Pollutant Exposure within Life Cycle Impact Assessment  

SciTech Connect

Neglecting health effects from indoor pollutant emissions and exposure, as currently done in Life Cycle Assessment (LCA), may result in product or process optimizations at the expense of workers? or consumers? health. To close this gap, methods for considering indoor exposure to chemicals are needed to complement the methods for outdoor human exposure assessment already in use. This paper summarizes the work of an international expert group on the integration of human indoor and outdoor exposure in LCA, within the UNEP/SETAC Life Cycle Initiative. A new methodological framework is proposed for a general procedure to include human-health effects from indoor exposure in LCA. Exposure models from occupational hygiene and household indoor air quality studies and practices are critically reviewed and recommendations are provided on the appropriateness of various model alternatives in the context of LCA. A single-compartment box model is recommended for use as a default in LCA, enabling one to screen occupational and household exposures consistent with the existing models to assess outdoor emission in a multimedia environment. An initial set of model parameter values was collected. The comparison between indoor and outdoor human exposure per unit of emission shows that for many pollutants, intake per unit of indoor emission may be several orders of magnitude higher than for outdoor emissions. It is concluded that indoor exposure should be routinely addressed within LCA.

Hellweg, Stefanie; Demou, Evangelia; Bruzzi, Raffaella; Meijer, Arjen; Rosenbaum, Ralph K.; Huijbregts, Mark A.J.; McKone, Thomas E.

2008-12-21T23:59:59.000Z

417

Proceedings: Eighth International Conference on Cycle Chemistry in Fossil and Combined Cycle Plants with Heat Recovery Steam Generators, June 20-22, 2006, Calgary, Alberta Canada  

Science Conference Proceedings (OSTI)

Proper selection, application, and optimization of the cycle chemistry have long been recognized as integral to ensuring the highest possible levels of component availability and reliability in fossil-fired generating plant units. These proceedings of the Eighth EPRI International Conference on Cycle Chemistry in Fossil Plants address state-of-the-art practices in conventional and combined cycle plants. The content provides a worldwide perspective on cycle chemistry practices, and insight as to industry ...

2007-03-20T23:59:59.000Z

418

Design and history matching of a waterflood/miscible CO? flood model of a mature field: the Wellman Unit, West Texas  

E-Print Network (OSTI)

The Wellman Unit is located in Terry County, West Texas. It is a Wolfcamp massive limestone reef. The reservoir is considered geologically unique due to the double cone-shape structure with a maximum closure of 825 feet above the OWOC. Three stages of depletion occurred over 50 years of production: 1) Primary depletion under a combination of solution gas drive and bottom water drive 2) Secondary recovery was initiated in 1979 via water injection into the flank of the reservoir and 3) CO? miscible injection was implemented in three wells on top of the structure in 1983. In this research, production and reservoir data was revised and integrated to develop a full field, 3-D, black oil simulation model. The primary objective was to reproduce via history matching, the historical performance of the reservoir under primary, secondary and tertiary stages of depletion. A secondary objective was developing a calibrated model that can be used to evaluate, design and plan future reservoir management decisions. To accomplish this task, a reservoir model was built that honors the structural configuration of the reservoir. A flexible grid system comprised of 16,767 grid blocks was built based on corner point - non orthogonal geometry. During the matching process, parameters were ranked according to uncertainty. The most uncertain parameter was the transmissibility and physical size of the under-lying aquifer system. Finally, the pseudo-miscible option based on the Todd and Longstaff theory was implemented as a modification to model behavior of the CO? miscible flood. The results can be summarized by the following: 1) History matching the primary depletion stage was satisfactory. 2) Extensive aquifer tuning was required to maintain sufficient reservoir pressure for CO? injection and match the field data during the waterflooding phase. 3) A complete pressure match was achieved through primary depletion, waterflooding and CO? injection, however the match on liquid production rate was compromised in order to tune the final pressure match from 1986-1995. The results of this work provide a foundation for future research into this hydraulically complicated reservoir. Once the complete calibrated model has been built, the simulation can be used to forecast future operations like blow-down or gas storage.

Rojas Barile, Jose Humberto

2002-01-01T23:59:59.000Z

419

Sustained Peak Low Cycle Fatigue: The Role of Coatings  

Science Conference Proceedings (OSTI)

The growth process continued by a combined process of oxidation and creep. ... of a model developed for crack growth during sustained peak low cycle fatigue.

420

Climate-Carbon Cycle Interactions Dr. John P. Krasting  

NLE Websites -- All DOE Office Websites (Extended Search)

Ensemble Modeling of Climate-Carbon Cycle Interactions Dr. John P. Krasting geophysical fluid dynamics Laboratory Wednesday, Jan 23, 2013 - 4:15PM MBG AUDITORIUM Refreshments at...

Note: This page contains sample records for the topic "modeling cycling units" 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

Life Cycle Assessment Comparing the Use of Jatropha Biodiesel...  

NLE Websites -- All DOE Office Websites (Extended Search)

both of NREL, lent their expertise in life cycle assessment modeling and Jatropha production, and Dr. Mark Pitterle of Symbiotic Engineering aided in the literature survey...

422

A new robust cycle-based inventory control policy  

E-Print Network (OSTI)

Abstract: In this paper, we propose a new robust cycle-based control policy for single installation inventory models with non-stationary uncertain demand.

423

Volatility dynamics of the US business cycle: A multivariate asymmetric GARCH approach  

Science Conference Proceedings (OSTI)

Most empirical investigations of the business cycles in the United States have excluded the dimension of asymmetric conditional volatility. This paper analyses the volatility dynamics of the US business cycle by comparing the performance of various multivariate ... Keywords: Constant correlations, E32, E37, Index of industrial production, Multivariate asymmetric GARCH, US business cycle non-linearities, Varying-correlations

Kin-Yip Ho; Albert K. Tsui; Zhaoyong Zhang

2009-05-01T23:59:59.000Z

424

The Anderson Quin Cycle  

SciTech Connect

The objective of this study was to make a more refined evaluation of the Anderson Quin Cycle based on most recent information on the performance of various elements that will be used in the Anderson Quin Cycle. My original estimate of the work plan for evaluating and optimizing the Anderson Quin Cycle called for 7000 man hours of work. Since this grant was limited to 2150 man hours, we could not expect to achieve all the objectives within the allotted period of work. However, the most relevant program objectives have been completed as reported here. The analysis generally confirms the results originally estimated in my paper on the subject. (Ref. 2) Further optimizations should show even higher efficiencies. The Anderson Quin Cycle (US Patent applied for) basically consists of 5 elements in the power cycle: A refrigeration system to cool and clean the inlet air before it enters the compressor that supplies air for the gas turbine; a gas turbine consisting of a compressor, combustor, and turbine; a steam boiler and steam turbine system using the heat from the exhaust gas out of the gas turbine; a vapor turbine cycle, which utilizes the condensed heat from the exhaust of the steam turbine and the exhaust gas heat leaving the steam boiler to operate a vapor turbine cycle which utilizes another fluid than water, in this case isobutane; and the fifth element consists of a gas cooler and heat pump system, which removes the heat from the exhaust gas to lower its temperature essentially to atmospheric temperature, and at the same time permits treatment of the exhaust gas to remove acid components such as sulfur dioxide and nitrogen oxides. Current industry accepted component characteristics were incorporated in the performance analysis of the overall cycle, ensuring accurate and meaningful operating predictions. The characteristics and performance of each of the elements are described. The thermal efficiency of the optimized calculated Anderson Quin Cycle is 62 percent.

Anderson, J.H.; Bilbow, W.M.

1993-03-18T23:59:59.000Z

425

Binary Cycle Power Plant | Open Energy Information  

Open Energy Info (EERE)

GEOTHERMAL ENERGYGeothermal Home GEOTHERMAL ENERGYGeothermal Home Binary Cycle Power Plant General List of Binary Plants Binary power plant process diagram - DOE EERE 2012 Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units. Low to moderately heated (below 400°F) geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point that water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines and subsequently, the generators. Binary cycle power plants are closed-loop systems and virtually nothing (except water vapor) is emitted to the atmosphere. Resources below 400°F

426

Overview of the nuclear fuel cycle  

SciTech Connect

The use of nuclear reactors to provide electrical energy has shown considerable growth since the first nuclear plant started commercial operation in the mid 1950s. Although the main purpose of this paper is to review the fuel cycle capabilities in the United States, the introduction is a brief review of the types of nuclear reactors in use and the world-wide nuclear capacity.

Leuze, R.E.

1982-01-01T23:59:59.000Z

427

Solar Augmented Steam Cycles: 2010 Industry Update  

Science Conference Proceedings (OSTI)

Several studies were performed to evaluate a range of solar augmented steam cycle design options. All the designs use steam generated by a solar field in a conventional steam cycle, either offsetting some of the fuel required to generate power or boosting plant power output. The scope of the studies included a conceptual design modeling effort to evaluate a broad range of solar integration design options for biomass and natural gas combined-cycle (NGCC) power plants and two detailed case studies at NGCC ...

2010-12-23T23:59:59.000Z

428

Primitive-Equation-Based Low-Order Models with Seasonal Cycle. Part II: Application to Complexity and Nonlinearity of Large-Scale Atmosphere Dynamics  

Science Conference Proceedings (OSTI)

A recently developed class of semiempirical low-order models is utilized for the reexamination of several aspects of the complexity and nonlinearity of large-scale dynamics in a GCM. Given their low dimensionality, these models are quite ...

Ulrich Achatz; J. D. Opsteegh

2003-02-01T23:59:59.000Z

429

The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model that aims to predict the future failure of rod pump units. Innovative and modern, this  

E-Print Network (OSTI)

increase the amount of usable oil retrieved from each well by the installed rod pump unit therefore that aims to predict the future failure of rod pump units. Innovative and modern, this novel technology provides a new approach to the maintenance of rod pumps through a system that increases efficiency while

Shahabi, Cyrus

430

The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model that aims to predict the future failure of rod pump units. Innovative and modern, this novel  

E-Print Network (OSTI)

increase the amount of usable oil retrieved from each well by the installed rod pump unit therefore that aims to predict the future failure of rod pump units. Innovative and modern, this novel technology provides a new approach to the maintenance of rod pumps through a system that increases efficiency while

Wang, Hai

431

Cycle isolation monitoring  

SciTech Connect

There are many factors to monitor in power plants, but one that is frequently overlooked is cycle isolation. Often this is an area where plant personnel can find 'low hanging fruit' with great return on investment, especially high energy valve leakage. This type of leakage leads to increased heat rate, potential valve damage and lost generation. The fundamental question to ask is 'What is 100 Btu/kW-hr of heat rate worth to your plant? On a 600 MW coal-fired power plant, a 1% leakage can lead to an 81 Btu/kW-hr impact on the main steam cycle and a 64 Btu/kW-hr impact on the hot reheat cycle. The article gives advice on methods to assist in detecting leaking valves and to monitor cycle isolation. A software product, TP. Plus-CIM was designed to estimate flow rates of potentially leaking valves.

Svensen, L.M. III; Zeigler, J.R.; Todd, F.D.; Alder, G.C. [Santee Copper, Moncks Corner, SC (United States)

2009-07-15T23:59:59.000Z

432

The Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

The Carbon Cycle The Carbon Cycle The global carbon cycle involves the carbon in and exchanging between the earth's atmosphere, fossil fuels, the oceans, and the vegetation and soils of the earth's terrestrial ecosystems. image Each year, the world's terrestrial ecosystems withdraw carbon from the atmosphere through photosynthesis and add it again through respiration and decay. A more detailed look at the global carbon cycle for the 1990s is shown below. The main annual fluxes in GtC yr-1 are: pre-industrial "natural" fluxes in black and "anthropogenic" fluxes in red (modified from Sarmiento and Gruber, 2006, with changes in pool sizes from Sabine et al., 2004a). The net terrestrial loss of -39 GtC is inferred from cumulative fossil fuel emissions minus atmospheric increase minus ocean storage. The loss of

433

Cycle Chemistry Improvement Program  

Science Conference Proceedings (OSTI)

The purity of water and steam is central to ensuring fossil plant component availability and reliability. This report, which describes formal cycle chemistry improvement programs at nine utilities, will assist utilities in achieving significant operation and maintenance cost reductions.

1997-04-21T23:59:59.000Z

434

Crude Oil Price Cycles  

Gasoline and Diesel Fuel Update (EIA)

The heating oil and diesel fuel price runups in late January were made even more problematic by coming on top of the high side of the latest crude market cycle. Over the past 10...

435

Crude Oil Price Cycles  

U.S. Energy Information Administration (EIA)

The heating oil and diesel price runups in late January were made even more problematic by coming on top of the high side of the latest crude market cycle.

436

The Annual Agricultural Cycle  

E-Print Network (OSTI)

. Sman shad agriculture 1.WAV Length of track 00:44:03 Related tracks (include description/relationship if appropriate) Title of track The Annual Agricultural Cycle Translation of title Description (to be used in archive entry...

Zla ba sgrol ma

2009-11-16T23:59:59.000Z

437

Avestar® - Syngas-Fired Combined Cycle Dynamic Simulator  

NLE Websites -- All DOE Office Websites (Extended Search)

Syngas-Fired Combined Cycle Dynamic Simulator Syngas-Fired Combined Cycle Dynamic Simulator The AVESTAR® center offers courses using the Combined Cycle Simulator, focusing on the power generation process after gasification. This simulator is well-suited for concentrated training on operation and control of the gas and steam turbines; condensate, feed water, and circulating water systems; heat recovery steam generator; and selective catalytic reduction (SCR) unit. Combined cycle simulator startup operations include bringing up the gas turbine to rated speed on natural gas and then switching over to the firing of synthesis gas. Key capabilities of the Combined Cycle Simulator include: Combined Cycle Simulator Operator training station HMI display for overview of Gas Turbine - Train A Normal base load operation

438

Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1  

SciTech Connect

This document presents a summary and framework of available transport data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater transport model. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

Nathan Bryant

2008-05-01T23:59:59.000Z

439

Phase I Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1  

Science Conference Proceedings (OSTI)

This document presents a summary and framework of the available hydrologic data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater flow models. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

Nathan Bryant

2008-05-01T23:59:59.000Z

440

Power conversion unit studies for the next generation nuclear plant coupled to a high-temperature steam electrolysis facility  

E-Print Network (OSTI)

The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold: 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in their early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were modeled using the process code HYSYS; a three-shaft design with 3 turbines and 4 compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with 3 stages of reheat were investigated. A high temperature steam electrolysis hydrogen production plant was coupled to the reactor and power conversion unit by means of an intermediate heat transport loop. Helium, CO2, and an 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative heat exchanger size and turbomachinery work were estimated for the different working fluids. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. Recommendations on the optimal working fluid for each configuration were made. The helium working fluid produced the highest overall plant efficiency for the three-shaft and reheat cycle; however, the nitrogen-helium mixture produced similar efficiency with smaller component sizes. The CO2 working fluid is recommend in the combined cycle configuration.

Barner, Robert Buckner

2006-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling cycling units" 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

Secular Cycles and Millennial Trends  

E-Print Network (OSTI)

both secular cycles and millennial up- ward trend dynamics.Cycles and Millennial Trends by Andrey Korotayev, ArtemySecular Cycles and Millennial Trends 1 Initially, we want to

Korotayev, Andrey V; Malkov, Artemy S; Khaltourina, Daria A

2006-01-01T23:59:59.000Z

442

Life-Cycle Analysis of Vehicle and Fuel Systems with the GREET Model - DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report  

NLE Websites -- All DOE Office Websites (Extended Search)

5 5 FY 2012 Annual Progress Report DOE Hydrogen and Fuel Cells Program Michael Wang (Primary Contact), Amgad Elgowainy, Jeongwoo Han and Hao Cai Argonne National Laboratory (ANL) ESD362 9700 South Cass Avenue Argonne, IL 60439 Phone: (630) 252-2819 Email: mqwang@anl.gov DOE Manager HQ: Fred Joseck Phone: (202) 586-7932 Email: Fred.Joseck@ee.doe.gov Project Start Date: October 2009 Project End Date: Project continuation and direction determined annually by DOE Fiscal Year (FY) 2012 Objectives Evaluate environmental benefits of hydrogen fuel * cell electric vehicles (FCEVs) with various renewable hydrogen production pathways relative to baseline gasoline pathways. Conduct vehicle-cycle analysis of hydrogen FCEVs. *

443

Advanced Fuel Cycle Cost Basis  

SciTech Connect

This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.

D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert; E. Schneider

2008-03-01T23:59:59.000Z

444

Advanced Fuel Cycle Cost Basis  

SciTech Connect

This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 26 cost modules—24 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, and high-level waste.

D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert

2007-04-01T23:59:59.000Z

445

Advanced Fuel Cycle Cost Basis  

SciTech Connect

This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.

D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert; E. Schneider

2009-12-01T23:59:59.000Z

446

Fuel Cycle and Isotopes Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Divisions Fuel Cycle and Isotopes Division Jeffrey Binder, Division Director Jeffrey Binder, Division Director The Fuel Cycle and Isotopes Division (FCID) of the Nuclear Science...

447

Computational Efficiency and Accuracy of Methods for Asynchronously Coupling Atmosphere-Ocean Climate Models. Part II: Testing with a Seasonal Cycle  

Science Conference Proceedings (OSTI)

The asynchronous coupling schemes used in the seasonal, coupled atmosphere–ocean general circulation models (A/O GCMs) of Manabe et al. 1979 and Washington et al. 1980 are tested in the seasonal, coupled atmosphere–ocean model of Harvey and ...

L. D. Danny Harvey

1986-01-01T23:59:59.000Z

448

The Impact of the Land Surface Physics in the Operational NCEP Eta Model on Simulating the Diurnal Cycle: Evaluation and Testing Using Oklahoma Mesonet Data  

Science Conference Proceedings (OSTI)

On 31 January 1996, the National Centers for Environmental Prediction/Environmental Modeling Center (NCEP/EMC) implemented a state-of-the-art land surface parameterization in the operational Eta Model. The purpose of this study is to evaluate and ...