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

Simple ocean carbon cycle models  

SciTech Connect (OSTI)

Simple ocean carbon cycle models can be used to calculate the rate at which the oceans are likely to absorb CO{sub 2} from the atmosphere. For problems involving steady-state ocean circulation, well calibrated ocean models produce results that are very similar to results obtained using general circulation models. Hence, simple ocean carbon cycle models may be appropriate for use in studies in which the time or expense of running large scale general circulation models would be prohibitive. Simple ocean models have the advantage of being based on a small number of explicit assumptions. The simplicity of these ocean models facilitates the understanding of model results.

Caldeira, K. [Lawrence Livermore National Lab., CA (United States); Hoffert, M.I. [New York Univ., NY (United States). Dept. of Earth System Sciences; Siegenthaler, U. [Bern Univ. (Switzerland). Inst. fuer Physik

1994-02-01T23:59:59.000Z

2

Verifiable Fuel Cycle Simulation Model (VISION): A Tool for Analyzing Nuclear Fuel Cycle Futures  

SciTech Connect (OSTI)

The nuclear fuel cycle consists of a set of complex components that are intended to work together. 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 such as how the system would respond to each technological change, a series of which moves the fuel cycle from where it is to a postulated future state. The system analysis working group of the United States research program on advanced fuel cycles (formerly called the Advanced Fuel Cycle Initiative) 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. For example, VISION users can now change yearly the selection of separation or reactor technologies, the performance characteristics of those technologies, and/or the routing of material among separation and reactor types - with the model still operating on a PC in <5 min.

Jacob J. Jacobson; Steven J. Piet; Gretchen E. Matthern; David E. Shropshire; Robert F. Jeffers; A. M. Yacout; Tyler Schweitzer

2010-11-01T23:59:59.000Z

3

VISION: Verifiable Fuel Cycle Simulation Model  

SciTech Connect (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

4

An Edge-based Formulation for the Combined-Cycle Units  

E-Print Network [OSTI]

Oct 1, 2014 ... Based on various combinations of combustion turbines (CTs) and steam turbines (STs), the combined-cycle unit could work at different ...

Lei Fan

2014-10-01T23:59:59.000Z

5

Modeling the Nuclear Fuel Cycle  

SciTech Connect (OSTI)

A review of existing nuclear fuel cycle systems analysis codes was performed to determine if any existing codes meet technical and functional requirements defined for a U.S. national program supporting the global and domestic assessment, development and deployment of nuclear energy systems. The program would be implemented using an interconnected architecture of different codes ranging from the fuel cycle analysis code, which is the subject of the review, to fundamental physical and mechanistic codes. Four main functions are defined for the code: (1) the ability to characterize and deploy individual fuel cycle facilities and reactors in a simulation, while discretely tracking material movements, (2) the capability to perform an uncertainty analysis for each element of the fuel cycle and an aggregate uncertainty analysis, (3) the inclusion of an optimization engine able to optimize simultaneously across multiple objective functions, and (4) open and accessible code software and documentation to aid in collaboration between multiple entities and facilitate software updates. Existing codes, categorized as annualized or discrete fuel tracking codes, were assessed according to the four functions and associated requirements. These codes were developed by various government, education and industrial entities to fulfill particular needs. In some cases, decisions were made during code development to limit the level of detail included in a code to ease its use or to focus on certain aspects of a fuel cycle to address specific questions. The review revealed that while no two of the codes are identical, they all perform many of the same basic functions. No code was able to perform defined function 2 or several requirements of functions 1 and 3. Based on this review, it was concluded that the functions and requirements will be met only with development of a new code, referred to as GENIUS.

Jacob J. Jacobson; Mary Lou Dunzik-Gougar; Christopher A. Juchau

2010-08-01T23:59:59.000Z

6

VISION: Verifiable Fuel Cycle Simulation Model  

SciTech Connect (OSTI)

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

7

A model for life cycle records management  

SciTech Connect (OSTI)

The primary objective of this paper is to update an old Records Management concept; the management of records according to the records life cycle. Accordingly, the authors are presenting a new version of the Records Management life cycle model and its associated elements. The basic concept is that every record progresses through three phases; a record is created, is used and maintained, and dispositioned. In this presentation, the authors update the very old straight line model and the more current circular model with a new model that essentially combines the two. The model portrays Records Management as having a distinct straight-line beginning, a circular use and maintenance phase, and a distinct straight-line end. The presentation maps Records Management Program elements and activities against the phases depicted in the model. The authors believe that this new records life cycle model is an enhanced physical representation of the process. This presentation is designed to help put all of the specialized Records Management topics that participants have heard about during the conference in the perspective of the records life cycle.

Tayfun, A.C.; Gibson, S.

1996-10-01T23:59:59.000Z

8

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

SciTech Connect (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

9

An approach to reduce start-up opacity on a coal-fired cycling unit  

SciTech Connect (OSTI)

Motivated by the need to prevent stack emission discharges even during start-up, an operations program was initiated to reduce opacity on a coal-fired cycling unit. The measurement basis is a numeric comparison of annual start-ups and yearly totals for reportable opacity six-minute averages. The unit of interest has been in commercial operation since 1978 and has experienced more than 1600 cycles of operation. The 46 gross megawatt fossil fuel unit has shown a rising capacity factor as cycling frequency has increased during the past years. This paper examines the effectiveness of the opacity reduction program and the experiences and methods required to achieve the results. 1986 reference data showed 122 reportable opacity occurrences for 145 unite start-ups. Combined 1988-89 records tabulated to 48 reportable opacity occurrences for 303 cycling operations.

Costello, P.A. (Illinois Power Co., Havana Power Station, Havana, IL (US))

1990-01-01T23:59:59.000Z

10

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

11

Uncertainty in Life Cycle Greenhouse Gas Emissions from United States Coal  

E-Print Network [OSTI]

analyses involving coal. Greenhouse gas emissions from fuel use and methane releases at coal mines, fuel.5 million metric tons of methane emissions. Close to 95% of domestic coal was consumed by the electricityUncertainty in Life Cycle Greenhouse Gas Emissions from United States Coal Aranya Venkatesh

Jaramillo, Paulina

12

Application and Operation of a 2-MW Organic Rankine Cycle System on a Refinery FCC Unit  

E-Print Network [OSTI]

The nation's largest organic Rankine cycle (ORC) waste heat recovery system was started up in July 1984 at a West Coast oil refinery. The system includes two hermetically sealed turbine-generator units, each rated at 1070 kW. Each turbine...

Drake, R. L.

13

Technical Cost Modeling - Life Cycle Analysis Basis for Program...  

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

Cost Modeling - Life Cycle Analysis Basis for Program Focus 2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer...

14

Software Requirements Specification Verifiable Fuel Cycle Simulation (VISION) Model  

SciTech Connect (OSTI)

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

15

Modelling cycle to cycle variations in an SI engine with detailed chemical kinetics  

SciTech Connect (OSTI)

This paper presents experimental results and a new computational model that investigate cycle to cycle variations (CCV) in a spark ignition (SI) engine. An established stochastic reactor model (SRM) previously used to examine homogeneous charge compression ignition (HCCI) combustion has been extended by spark initiation, flame propagation and flame termination sub-models in order to simulate combustion in SI engines. The model contains a detailed chemical mechanism but relatively short computation times are achieved. The flame front is assumed to be spherical and centred at the spark location, and a pent roof and piston bowl geometry are accounted for. The model is validated by simulating the pressure profile and emissions from an iso-octane fuelled single cylinder research engine that showed low CCV. The effects of key parameters are investigated. Experimental results that show cycle to cycle fluctuations in a four-cylinder naturally aspirated gasoline fuelled SI engine are presented. The model is then coupled with GT-Power, a one-dimensional engine simulation tool, which is used to simulate the breathing events during a multi-cycle simulation. This allows an investigation of the cyclic fluctuations in peak pressure. The source and magnitude of nitric oxide (NO) emissions produced by different cycles are then investigated. It was found that faster burning cycles result in increased NO emissions compared with cycles that have a slower rate of combustion and that more is produced in the early stages of combustion compared with later in the cycle. The majority of NO was produced via the thermal mechanism just after combustion begins. (author)

Etheridge, Jonathan; Mosbach, Sebastian; Kraft, Markus [Department of Chemical Engineering and Biotechnology, University of Cambridge (United Kingdom); Wu, Hao; Collings, Nick [Department of Engineering, University of Cambridge (United Kingdom)

2011-01-15T23:59:59.000Z

16

VISION User Guide - VISION (Verifiable Fuel Cycle Simulation) Model  

SciTech Connect (OSTI)

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; 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 for U.S. nuclear power. 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 of 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. Note that recovered uranium is itself often partitioned: some RU flows with recycled transuranic elements, some flows with wastes, and the rest is designated RU. RU comes out of storage if needed to correct the U/TRU ratio in new recycled fuel. Neither RU nor DU are designated as wastes. 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. We use Microsoft Excel 2003 and have not tested VISION with Microsoft Excel 2007. The VISION team uses both Powersim Studio 2005 and 2009 and it should work with either.

Jacob J. Jacobson; Robert F. Jeffers; Gretchen E. Matthern; Steven J. Piet; Benjamin A. Baker; Joseph Grimm

2009-08-01T23:59:59.000Z

17

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

SciTech Connect (OSTI)

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

18

Implications of changing natural gas prices in the United States electricity sector for SO and life cycle GHG emissions  

E-Print Network [OSTI]

to the choice of coal over natural gas. External incentives such as low natural gas prices compared to coalImplications of changing natural gas prices in the United States electricity sector for SO 2 , NO X of changing natural gas prices in the United States electricity sector for SO2, NOX and life cycle GHG

Jaramillo, Paulina

19

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

20

DESIGNER INTEGRATION IN TRAINING CYCLES : IEEE LTSA MODEL ADAPTATION  

E-Print Network [OSTI]

DESIGNER INTEGRATION IN TRAINING CYCLES : IEEE LTSA MODEL ADAPTATION Alain Corbière & Chistophe as the distance learning platform architectures such as IEEE LTSA (Learning and Training System Architecture of the course's progression. It is based on the LTSA architectural model and the studies on the Learning Object

Boyer, Edmond

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

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

SciTech Connect (OSTI)

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

22

Geothermal completion technology life-cycle cost model (GEOCOM)  

SciTech Connect (OSTI)

GEOCOM is a model developed to evaluate the cost effectiveness of alternative technologies used in the completion, production, and maintenance of geothermal wells. The model calculates the ratio of life-cycle cost to life-cycle production or injection and thus is appropriate for evaluating the cost effectiveness of a geothermal well even when the most economically profitable well completion strategies do not result in lowest capital costs. The project to develop the GEOCOM model included the establishment of a data base for studying geothermal completions and preliminary case/sensitivity studies. The code has the data base built into its structure as default parameters. These parameters include geothermal resource characteristics; costs of geothermal wells, workovers, and equipment; and other data. The GEOCOM model has been written in ANSI (American National Standard Institute) FORTRAN 1966 version.

Mansure, A.J.; Carson, C.C.

1982-01-01T23:59:59.000Z

23

Scale-4 Analysis of Pressurized Water Reactor Critical Configurations: Volume 4-Three Mile Island Unit 1 Cycle 5  

SciTech Connect (OSTI)

The requirements of ANSI/ANS-8.1 specify that calculational methods for away-from-reactor criticality safety analyses be validated against experimental measurements. If credit is to be taken for the reduced reactivity of burned or spent fuel relative to its original ''fresh'' composition, it is necessary to benchmark computational methods used in determining such reactivity worth against spent fuel reactivity measurements. This report summarizes a portion of the ongoing effort to benchmark away-from-reactor criticality analysis methods using relevant and well-documented critical configurations from commercial pressurized water reactors. The analysis methodology utilized for all calculations in this report is based on the modules and data associated with the SCALE-4 code system. Isotopic densities for spent fuel assemblies in the core were calculated using the SCALE-4 SAS2H analytical sequence. The sources of data and the procedures for deriving SAS2H input parameters are described in detail. The SNIKR code family was used to extract the necessary isotopic densities from SAS2H results and to provide the data in the format required for SCALE criticality analysis modules. The CSASN analytical sequence in SCALE-4 was used to perform resonance processing of cross sections. The KENO V.a module of SCALE-4 was used to calculate the effective multiplication factor (k{sub eff}) for the critical configuration. The SCALE-4 27-group burnup library containing ENDF/B-IV (actinides) and ENDF/B-V (fission products) data was used for all calculations. This volume of the report documents a reactor critical calculation for GPU Nuclear Corporation's Three Mile Island Unit 1 (TMI-1) during hot, zero-power startup testing for the beginning of cycle 5. This unit and cycle were selected because of their relevance in spent fuel benchmark applications: (1) cycle 5 startup occurred after an especially long downtime of 6.6 years; and (2) the core consisted primarily (75%) of burned fuel, with all fresh fuel loaded on the core outer periphery. A k{sub eff} value of 0.9978 {+-} 0.0004 was obtained using two million neutron histories in the KENO V.a model. This result is close to the known critical k{sub eff} of 1.0 for the actual core and is consistent with other mixed-oxide criticality benchmarks. Thus this method is shown to be valid for spent fuel applications in burnup credit analyses.

DeHart, M.D.

1995-01-01T23:59:59.000Z

24

Watts Bar Unit 1 Cycle Zero Power Physics Tests Analysis with VERA-CS  

SciTech Connect (OSTI)

The Consortium for Advanced Simulation of Light Water Reactors (CASL) is developing a collection of methods and software products known as VERA, the Virtual Environment for Reactor Applications, including a core simulation capability called VERA-CS. A key milestone for this endeavor is to validate VERA against measurements from operating nuclear power reactors. The first step in validation against plant data is to determine the ability of VERA to accurately simulate the initial startup physics tests for Watts Bar Nuclear Power Station, Unit 1 (WBN1) cycle 1. VERA-CS calculations were performed with the Insilico code developed at ORNL using cross section processing from the SCALE system and the transport capabilities within the Denovo transport code using the SPN method. The calculations were performed with ENDF/B-VII.0 cross sections in 252 groups (collapsed to 23 groups for the 3D transport solution). The key results of the comparison of calculations with measurements include initial criticality, control rod worth critical configurations, control rod worth, differential boron worth, and isothermal temperature reactivity coefficient (ITC). The VERA results for these parameters show good agreement with measurements, with the exception of the ITC, which requires additional investigation. Results are also compared to those obtained with Monte Carlo methods and a current industry core simulator.

Gehin, Jess C [ORNL; Godfrey, Andrew T [ORNL; Evans, Thomas M [ORNL; Hamilton, Steven P [ORNL; Francheschini, F. [Westinghouse Electric Company, Cranberry Township

2014-01-01T23:59:59.000Z

25

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

E-Print Network [OSTI]

Area, Chicago, and New York City  are  evaluated  capturing  passenger  transportation  life?cycle  energy Area, Chicago, and New York City are evaluated capturing passenger trans- portation life-cycle energy

Chester, Mikhail V

2008-01-01T23:59:59.000Z

26

Increase of Carbon Cycle Feedback with Climate Sensitivity: Results from a coupled Climate and Carbon Cycle Model  

SciTech Connect (OSTI)

Coupled climate and carbon cycle modeling studies have shown that the feedback between global warming and the carbon cycle, in particular the terrestrial carbon cycle, could accelerate climate change and result in larger warming. In this paper, we investigate the sensitivity of this feedback for year-2100 global warming in the range of 0 K to 8 K. Differing climate sensitivities to increased CO{sub 2} content are imposed on the carbon cycle models for the same emissions. Emissions from the SRES A2 scenario are used. We use a fully-coupled climate and carbon cycle model, the INtegrated Climate and CArbon model (INCCA) the NCAR/DOE Parallel Coupled Model coupled to the IBIS terrestrial biosphere model and a modified-OCMIP ocean biogeochemistry model. In our model, for scenarios with year-2100 global warming increasing from 0 to 8 K, land uptake decreases from 47% to 29% of total CO{sub 2} emissions. Due to competing effects, ocean uptake (16%) shows almost no change at all. Atmospheric CO{sub 2} concentration increases were 48% higher in the run with 8 K global climate warming than in the case with no warming. Our results indicate that carbon cycle amplification of climate warming will be greater if there is higher climate sensitivity to increased atmospheric CO{sub 2} content; the carbon cycle feedback factor increases from 1.13 to 1.48 when global warming increases from 3.2 to 8 K.

Govindasamy, B; Thompson, S; Mirin, A; Wickett, M; Caldeira, K; Delire, C

2004-04-01T23:59:59.000Z

27

The Influence of Photosynthesis on the Number of Metamers per Growth Unit in GreenLab Model  

E-Print Network [OSTI]

1 The Influence of Photosynthesis on the Number of Metamers per Growth Unit in GreenLab Model A cycle, new organs are created with respect to genetic rules) and photosynthesis (organs are filled with the biomass produced by the leaves photosynthesis). Our new developments of the model concern the retroaction

Paris-Sud XI, Université de

28

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

29

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

30

Process integrated modelling for steelmaking Life Cycle Inventory analysis  

SciTech Connect (OSTI)

During recent years, strict environmental regulations have been implemented by governments for the steelmaking industry in order to reduce their environmental impact. In the frame of the ULCOS project, we have developed a new methodological framework which combines the process integrated modelling approach with Life Cycle Assessment (LCA) method in order to carry out the Life Cycle Inventory of steelmaking. In the current paper, this new concept has been applied to the sinter plant which is the most polluting steelmaking process. It has been shown that this approach is a powerful tool to make the collection of data easier, to save time and to provide reliable information concerning the environmental diagnostic of the steelmaking processes.

Iosif, Ana-Maria [Arcelor Research, Voie Romaine, BP30320, Maizieres-les-Metz, 57283 (France)], E-mail: ana-maria.iosif@arcelormittal.com; Hanrot, Francois [Arcelor Research, Voie Romaine, BP30320, Maizieres-les-Metz, 57283 (France)], E-mail: francois.hanrot@arcelormittal.com; Ablitzer, Denis [LSG2M, Ecole des Mines de Nancy, Parc de Saurupt, F-54042 Nancy cedex (France)], E-mail: denis.ablitzer@mines.inpl-nancy.fr

2008-10-15T23:59:59.000Z

31

Computer modeling of corrosion in absorption cooling cycles  

SciTech Connect (OSTI)

A comprehensive model has been developed for the computation of corrosion rates of carbon steels in the presence of lithium bromide-based brines that are used as working fluids for absorption refrigeration cycles. The model combines a thermodynamic model that provides realistic speciation of aqueous systems with an electrochemical model for partial cathodic and anodic processes on the metal surface. The electrochemical model includes the adsorption of halides, which strongly influences the corrosion process. Also, the model takes into account the formation of passive films, which become important at high temperatures, at which the refrigeration equipment operates. The model has been verified by comparing calculated corrosion rates with laboratory data for carbon steels in LiBr solutions. Good agreement between the calculated and experimental corrosion rates has been obtained. In particular, the model is capable of reproducing the effects of changes in alkalinity and molybdate concentration on the rates of general corrosion. The model has been incorporated into a program that makes it possible to analyze the effects of various conditions such as temperature, pressure, solution composition or flow velocity on corrosion rates.

Anderko, A.; Young, R.D. [OLI Systems Inc., Morris Plains, NJ (United States)

1999-11-01T23:59:59.000Z

32

The FIT Model - Fuel-cycle Integration and Tradeoffs  

SciTech Connect (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

33

A Simulation Model for the Waterfall Software Development Life Cycle  

E-Print Network [OSTI]

Software development life cycle or SDLC for short is a methodology for designing, building, and maintaining information and industrial systems. So far, there exist many SDLC models, one of which is the Waterfall model which comprises five phases to be completed sequentially in order to develop a software solution. However, SDLC of software systems has always encountered problems and limitations that resulted in significant budget overruns, late or suspended deliveries, and dissatisfied clients. The major reason for these deficiencies is that project directors are not wisely assigning the required number of workers and resources on the various activities of the SDLC. Consequently, some SDLC phases with insufficient resources may be delayed; while, others with excess resources may be idled, leading to a bottleneck between the arrival and delivery of projects and to a failure in delivering an operational product on time and within budget. This paper proposes a simulation model for the Waterfall development proce...

Bassil, Youssef

2012-01-01T23:59:59.000Z

34

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

E-Print Network [OSTI]

energy  and  GHG performance of Chicago and New York is the Chicago and New York systems where energy and  emissions CO 2 e).  For New York, life?cycle energy and GHG emissions 

Chester, Mikhail V

2008-01-01T23:59:59.000Z

35

Virtual Community Life Cycle: a Model to Develop Systems with Fluid Requirements Christo El Morr1  

E-Print Network [OSTI]

1 Virtual Community Life Cycle: a Model to Develop Systems with Fluid Requirements Christo El Morr1 into the life cycle model needed to develop information systems for group of people with fluid requirements development life cycles can be followed when developing any virtual community. Though, in a fluid environment

Paris-Sud XI, Université de

36

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

37

Response Surface Energy Modeling of an Electric Vehicle over a Reduced Composite Drive Cycle  

SciTech Connect (OSTI)

Response surface methodology (RSM) techniques were applied to develop a predictive model of electric vehicle (EV) energy consumption over the Environmental Protection Agency's (EPA) standardized drive cycles. The model is based on measurements from a synthetic composite drive cycle. The synthetic drive cycle is a minimized statistical composite of the standardized urban (UDDS), highway (HWFET), and US06 cycles. The composite synthetic drive cycle is 20 minutes in length thereby reducing testing time of the three standard EPA cycles by over 55%. Vehicle speed and acceleration were used as model inputs for a third order least squared regression model predicting vehicle battery power output as a function of the drive cycle. The approach reduced three cycles and 46 minutes of drive time to a single test of 20 minutes. Application of response surface modeling to the synthetic drive cycle is shown to predict energy consumption of the three EPA cycles within 2.6% of the actual measured values. Additionally, the response model may be used to predict energy consumption of any cycle within the speed/acceleration envelope of the synthetic cycle. This technique results in reducing test time, which additionally provides a model that may be used to expand the analysis and understanding of the vehicle under consideration.

Jehlik, Forrest [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); LaClair, Tim J [ORNL] [ORNL

2014-01-01T23:59:59.000Z

38

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

39

Land Use Change Effects on Forest Carbon Cycling Throughout the Southern United States  

E-Print Network [OSTI]

and deforestation on carbon cycling in forest floor and soil from 1900 to 2050 throughout 13 states in the southern because afforestation causes a gradual gain in carbon stocks for many decades, while deforestation causes Tg C, and deforestation caused emission of 49 Tg C. However, the net effect of land use change

40

Partially linear models with unit roots  

E-Print Network [OSTI]

in the regression and consider Dy t H11005dy tH110021 H11001utH11001 ( jH110051 p p j Dy tH11002j H11001g~x t !H11001e t , (2.4) where t is a simple time trend+ In practice, ~2+4! would be used to test if a series has a unit root with a drift versus ~linear! trend... with these regressors+ Thus, corresponding to regression ~2+3!, z t H11005 ~y tH110021 , Dy tH110021 ,+++,Dy tH11002p ! ' ,gH11005~d,p 1 ,+++,p p ! H11477 ; and corresponding to regression ~2+4!, z t H11005~y tH110021 ,t,Dy tH110021 ,+++,Dy tH11002p ! H11477 ,gH11005~d...

Juhl, Ted P.; Xiao, Z. J.

2005-10-01T23:59:59.000Z

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.


41

Frost Growth CFD Model of an Integrated Active Desiccant Rooftop Unit  

SciTech Connect (OSTI)

A frost growth model is incorporated into a Computational Fluid Dynamics (CFD) simulation of a heat pump by means of a user-defined function in FLUENT, a commercial CFD code. The transient model is applied to the outdoor section of an Integrated Active Desiccant Rooftop (IADR) unit in heating mode. IADR is a hybrid vapor compression and active desiccant unit capable of handling 100% outdoor air (dedicated outdoor air system) or as a total conditioning system, handling both outdoor air and space cooling or heating loads. The predicted increase in flow resistance and loss in heat transfer capacity due to frost build-up are compared to experimental pressure drop readings and thermal imaging. The purpose of this work is to develop a CFD model that is capable of predicting frost growth, an invaluable tool in evaluating the effectiveness of defrost-on-demand cycles.

Geoghegan, Patrick J [ORNL; Petrov, Andrei Y [ORNL; Vineyard, Edward Allan [ORNL; Zaltash, Abdolreza [ORNL; Linkous, Randall Lee [ORNL

2008-01-01T23:59:59.000Z

42

An energetic perspective on hydrological cycle changes in the Geoengineering Model Intercomparison Project  

E-Print Network [OSTI]

An energetic perspective on hydrological cycle changes in the Geoengineering Model Intercomparison-ocean general circulation models simulating experiment G1 of the Geoengineering Model Intercomparison Project perspective on hydrological cycle changes in the Geoengineering Model Intercomparison Project, J. Geophys. Res

Robock, Alan

43

Integrating repositories with fuel cycles: The airport authority model  

SciTech Connect (OSTI)

The organization of the fuel cycle is a legacy of World War II and the cold war. Fuel cycle facilities were developed and deployed without consideration of the waste management implications. This led to the fuel cycle model of a geological repository site with a single owner, a single function (disposal), and no other facilities on site. Recent studies indicate large economic, safety, repository performance, nonproliferation, and institutional incentives to collocate and integrate all back-end facilities. Site functions could include geological disposal of spent nuclear fuel (SNF) with the option for future retrievability, disposal of other wastes, reprocessing with fuel fabrication, radioisotope production, other facilities that generate significant radioactive wastes, SNF inspection (navy and commercial), and related services such as SNF safeguards equipment testing and training. This implies a site with multiple facilities with different owners sharing some facilities and using common facilities - the repository and SNF receiving. This requires a different repository site institutional structure. We propose development of repository site authorities modeled after airport authorities. Airport authorities manage airports with government-owned runways, collocated or shared public and private airline terminals, commercial and federal military facilities, aircraft maintenance bases, and related operations - all enabled and benefiting the high-value runway asset and access to it via taxi ways. With a repository site authority the high value asset is the repository. The SNF and HLW receiving and storage facilities (equivalent to the airport terminal) serve the repository, any future reprocessing plants, and others with needs for access to SNF and other wastes. Non-public special-built roadways and on-site rail lines (equivalent to taxi ways) connect facilities. Airport authorities are typically chartered by state governments and managed by commissions with members appointed by the state governor, county governments, and city governments. This structure (1) enables state and local governments to work together to maximize job and tax benefits to local communities and the state, (2) provides a mechanism to address local concerns such as airport noise, and (3) creates an institutional structure with large incentives to maximize the value of the common asset, the runway. A repository site authority would have a similar structure and be the local interface to any national waste management authority. (authors)

Forsberg, C. [Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 (United States)

2012-07-01T23:59:59.000Z

44

Model Predictive Control of Integrated Gasification Combined Cycle Power Plants  

SciTech Connect (OSTI)

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

45

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

SciTech Connect (OSTI)

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

46

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

SciTech Connect (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

47

Three-dimensional model synthesis of the global methane cycle  

E-Print Network [OSTI]

39, Ehhalt, D. H. , The atmo•heric cycle of methane, Tellugworld-wide increase in t•heric methane, 1978-1987, Science,

1991-01-01T23:59:59.000Z

48

Heavy Duty & Medium Duty Drive Cycle Data Collection for Modeling...  

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

Duty Cycle and Performance Data Collection and Analysis Program Vehicle Technologies Office Merit Review 2014: Powertrain Controls Optimization for Heavy Duty Line Haul Trucks...

49

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.

50

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

51

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

52

Election Results and Opportunistic Policies: A New Test of the Rational Political Business Cycle Model  

E-Print Network [OSTI]

Election Results and Opportunistic Policies: A New Test of the Rational Political Business Cycle Model#3; Toke S. Aidtay Francisco José Veigab Linda Gonçalves Veigac aUniversity of Cambridge, Faculty of Economics, Sidgwick Avenue Cambridge, CB3 9DD... . These results are consistent with the theoretical model. Keywords: Voting and popularity functions, opportunism, rational political busi- ness cycles, local government, system estimation, Portugal. JEL codes: D72, E32, H72. #3;The authors acknowledge helpful...

Aidt, Toke S; Veiga, F J; Veiga, L G

53

The 6th International Conference on Life Cycle Management in Gothenburg 2013 TOWARD A STRUCTURED FUNCTIONAL UNIT DEFINITION  

E-Print Network [OSTI]

Chatenay-Malabry, France. *E-mail: francois.cluzel@ecp.fr Keywords: Life Cycle Assessment (LCA), Goal of comparable product quantities to provide reliable Life Cycle Assessment (LCA) results. Although definition framework. INTRODUCTION Life Cycle Assessment (LCA) is performed in product design to measure

Boyer, Edmond

54

Comparative evaluation of life cycle assessment models for solid waste management  

SciTech Connect (OSTI)

This publication compares a selection of six different models developed in Europe and America by research organisations, industry associations and governmental institutions. The comparison of the models reveals the variations in the results and the differences in the conclusions of an LCA study done with these models. The models are compared by modelling a specific case - the waste management system of Dresden, Germany - with each model and an in-detail comparison of the life cycle inventory results. Moreover, a life cycle impact assessment shows if the LCA results of each model allows for comparable and consecutive conclusions, which do not contradict the conclusions derived from the other models' results. Furthermore, the influence of different level of detail in the life cycle inventory of the life cycle assessment is demonstrated. The model comparison revealed that the variations in the LCA results calculated by the models for the case show high variations and are not negligible. In some cases the high variations in results lead to contradictory conclusions concerning the environmental performance of the waste management processes. The static, linear modelling approach chosen by all models analysed is inappropriate for reflecting actual conditions. Moreover, it was found that although the models' approach to LCA is comparable on a general level, the level of detail implemented in the software tools is very different.

Winkler, Joerg [Institute for Waste Management and Contaminated Sites Treatment, TU Dresden Faculty of Forestry, Geo and Hydro Sciences, Pratzschwitzer Str. 15, 01796 Pirna (Germany); Bilitewski, Bernd [Institute for Waste Management and Contaminated Sites Treatment, TU Dresden Faculty of Forestry, Geo and Hydro Sciences, Pratzschwitzer Str. 15, 01796 Pirna (Germany)], E-mail: abfall@rcs.urz.tu-dresden.de

2007-07-01T23:59:59.000Z

55

Multi-century Changes to Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model  

SciTech Connect (OSTI)

In this paper, we use a coupled climate and carbon cycle model to investigate the global climate and carbon cycle changes out to year 2300 that would occur if CO{sub 2} emissions from all the currently estimated fossil fuel resources were released to the atmosphere. By year 2300, the global climate warms by about 8 K and atmospheric CO{sub 2} reaches 1423 ppmv. The warming is higher than anticipated because the sensitivity to radiative forcing increases as the simulation progresses. In our simulation, the rate of emissions peak at over 30 PgC yr{sup -1} early in the 22nd century. Even at year 2300, nearly 50% of cumulative emissions remain in the atmosphere. In our simulations both soils and living biomass are net carbon sinks throughout the simulation. Despite having relatively low climate sensitivity and strong carbon uptake by the land biosphere, our model projections suggest severe long-term consequences for global climate if all the fossil-fuel carbon is ultimately released to the atmosphere.

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

2005-02-17T23:59:59.000Z

56

Four-component united-atom model of bitumen  

E-Print Network [OSTI]

We propose a four-component molecular model of bitumen. The model includes realistic chemical constituents and introduces a coarse-graining level that suppresses the highest frequency modes. Molecular dynamics simulations of the model are being carried out using Graphic-Processor-Units based software in time spans in order of microseconds, and this enables the study of slow relaxation processes characterizing bitumen. This paper focuses on the high-temperature dynamics as expressed through the mean-square displacement, the stress autocorrelation function, and rotational relaxation. The diffusivity of the individual molecules changes little as a function of temperature and reveals distinct dynamical time scales as a result of the different constituents in the system. Different time scales are also observed for the rotational relaxation. The stress autocorrelation function features a slow non-exponential decay for all temperatures studied. From the stress autocorrelation function, the shear viscosity and shear ...

Hansen, Jesper S; Nielsen, Erik; Dyre, Jeppe C; Schrøder, Thomas B

2013-01-01T23:59:59.000Z

57

Cycle Life Modeling of Lithium-Ion Batteries Gang Ning* and Branko N. Popov**,z  

E-Print Network [OSTI]

Cycle Life Modeling of Lithium-Ion Batteries Gang Ning* and Branko N. Popov**,z Department and Newman4 made a first attempt to model the parasitic reactions in lithium-ion batteries by incorporating a solvent oxidation into a lithium-ion battery model. Spotnitz5 developed polynomial expressions

Popov, Branko N.

58

Electrochimica Acta 51 (2006) 20122022 A generalized cycle life model of rechargeable Li-ion batteries  

E-Print Network [OSTI]

­discharge model to simulate the cycle life behavior of rechargeable Li-ion batteries has been developed. The model and Newman [4] made a first attempt to model the parasitic reaction in Li-ion batteries by assuming a solvent and reversible capacity loss due to the growth and dissolution of SEI film in Li-ion batteries. Ramadass et al

Popov, Branko N.

59

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

SciTech Connect (OSTI)

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

60

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  

SciTech Connect (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

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

Thesis: Transient Modeling and Construc3on of a Fluid Based Electrocaloric Effect (ECE) Refrigera3on Cycle  

E-Print Network [OSTI]

Thesis: Transient Modeling and Construc3on of a Fluid Based Electrocaloric Effect (ECE) Refrigera3on Cycle Nathan Haggerty M.S. Student Mechanical · Demonstrate the feasibility of a fluid based electrocaloric refrigera3on cycle · ECE

Wisconsin at Madison, University of

62

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

SciTech Connect (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

63

Alternative water sources: Desalination model provides life-cycle costs of facility  

E-Print Network [OSTI]

Story by Danielle Supercinski tx H2O | pg. 8 Alternative water sourcees Desalination model provides life-cycle costs of facility platform and design standards as DESAL ECONOMICS?, but created to analyze con- ventional surface water treatment... to determine the economic and financial life-cycle costs of building and operating four water treatment facilities in South Texas. One facility was the Southmost Regional Water Authority Regional Desalination Plant near Brownsville. Sturdi- vant said...

Supercinski, Danielle

2009-01-01T23:59:59.000Z

64

Performance of VAV Fan Powered Terminal Units: Experimental Results and Models for Parallel Units  

E-Print Network [OSTI]

consists of a central air handling unit (AHU), where air is cooled by cooling coils (Wendes 1994). This air, referred to as primary air, is sent through a single-duct supply system to VAV terminal units by the supply fan. Each terminal unit is ducted to air... surprise that the flow regressed well with the square root of the pressure differential across the terminal unit at a given damper setting and showed no dependence on SCR. The construction quality of these terminal units could be an item of concern...

Furr, J.; O'Neal, D.; Davis, M.; Bryant, J.; Cramlet, A.

65

Hanford River Protection Project Life cycle Cost Modeling Tool to Enhance Mission Planning - 13396  

SciTech Connect (OSTI)

The Life cycle Cost Model (LCM) Tool is an overall systems model that incorporates budget, and schedule impacts for the entire life cycle of the River Protection Project (RPP) mission, and is replacing the Hanford Tank Waste Operations Simulator (HTWOS) model as the foundation of the RPP system planning process. Currently, the DOE frequently requests HTWOS simulations of alternative technical and programmatic strategies for completing the RPP mission. Analysis of technical and programmatic changes can be performed with HTWOS; however, life cycle costs and schedules were previously generated by manual transfer of time-based data from HTWOS to Primavera P6. The LCM Tool automates the preparation of life cycle costs and schedules and is needed to provide timely turnaround capability for RPP mission alternative analyses. LCM is the simulation component of the LCM Tool. The simulation component is a replacement of the HTWOS model with new capability to support life cycle cost modeling. It is currently deployed in G22, but has been designed to work in any full object-oriented language with an extensive feature set focused on networking and cross-platform compatibility. The LCM retains existing HTWOS functionality needed to support system planning and alternatives studies going forward. In addition, it incorporates new functionality, coding improvements that streamline programming and model maintenance, and capability to input/export data to/from the LCM using the LCM Database (LCMDB). The LCM Cost/Schedule (LCMCS) contains cost and schedule data and logic. The LCMCS is used to generate life cycle costs and schedules for waste retrieval and processing scenarios. It uses time-based output data from the LCM to produce the logic ties in Primavera P6 necessary for shifting activities. The LCM Tool is evolving to address the needs of decision makers who want to understand the broad spectrum of risks facing complex organizations like DOE-RPP to understand how near-term programmatic decisions affect life cycle costs and commitments. (authors)

Dunford, Gary [AEM Consulting, LLC, 1201 Jadwin Avenue, Richland, WA 99352 (United States)] [AEM Consulting, LLC, 1201 Jadwin Avenue, Richland, WA 99352 (United States); Williams, David [WIT, Inc., 11173 Oak Fern Court, San Diego, CA 92131 (United States)] [WIT, Inc., 11173 Oak Fern Court, San Diego, CA 92131 (United States); Smith, Rick [Knowledge Systems Design, Inc., 13595 Quaker Hill Cross Rd, Nevada City, CA 95959 (United States)] [Knowledge Systems Design, Inc., 13595 Quaker Hill Cross Rd, Nevada City, CA 95959 (United States)

2013-07-01T23:59:59.000Z

66

Modeling long-term CO2 storage, sequestration and cycling  

SciTech Connect (OSTI)

The application of numerical and analytical models to the problem of storage, sequestration and migration of carbon dioxide in geologic formations is discussed. A review of numerical and analytical models that have been applied to CO2 sequestration are presented, as well as a description of frameworks for risk analysis. Application of models to various issues related to carbon sequestration are discussed, including trapping mechanisms, density convection mixing, impurities in the CO2 stream, changes in formation porosity and permeability, the risk of vertical leakage, and the impacts on groundwater resources if leakage does occur. A discussion of the development and application of site-specific models first addresses the estimation of model parameters and the use of natural analogues to inform the development of CO2 sequestration models, and then surveys modeling that has been done at two commercial-scale CO2 sequestration sites, Sleipner and In Salah, along with a pilot-scale injection sites used to study CO2 sequestration in saline aquifers (Frio) and an experimental site designed to test monitoring of CO2 leakage in the vadose zone (ZERT Release Facility).

Bacon, Diana H.

2013-11-11T23:59:59.000Z

67

Duty cycle generator for average model of buck converter with current-mode control -- Using analog behavioral modeling of PSpice  

SciTech Connect (OSTI)

This paper presents a duty cycle generator for an average model of buck converter with current-mode control, which can simultaneously deal with both the continuous conduction model (CCM) and the discontinuous conduction mode (DCM). First, a duty cycle generator is mathematically derived, considering the transient-state of the current-loop. This technique plays an important role when the operating modes are changed under a considerable amount of step load change. Second, taking advantage of the analog behavioral modeling of PSpice, duty cycle generators for both the time and frequency domain analyses are built into a PSpice file. The accuracy of these models is verified through the computer simulations, which is compared to the actual circuit for the time domain analysis and the small signal model for the frequency analysis.

Hong, S.S. [Hyundai Electronics Industries Co., Ltd., Kyoungki-Do (Korea, Republic of); Jo, B.R. [LG Electronics Inc., Seoul (Korea, Republic of). Image and Media Lab.; Youn, M.J. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Electrical Engineering

1996-11-01T23:59:59.000Z

68

A nonstoichiometric structural model to characterize changes in the nickel hydroxide electrode during cycling  

SciTech Connect (OSTI)

Experimental capacities and mass changes are recorded using an electrochemical quartz crystal microbalance during the first 9 charge and discharge cycles of nickel hydroxide thin films cycled in 3.0 weight percent (wt%) potassium hydroxide electrolyte. For the first time, the film capacities have been corrected for the oxygen evolution side reaction, and the data used as input into the point defect-containing structural model to track the changes that occur during short-term cycling. Variations in capacity and mass during formation and charge/discharge cycling are related to changes in the point defect parameters, thus providing a structural origin for the unique experimental variations observed here and often reported in the literature, but previously unexplained. Proton-, potassium-, and water-content vary in the active material during charge/discharge cycling. The observed capacity loss, or ''capacity fade'', is explained by incomplete incorporation of potassium ions in (or near) the nickel vacancy during charge, as additional protons are then allowed to occupy the vacant lattice site. The increase in water content during reduction parallels the expansion of the electrode that is well known during cycling. This result confirms the origin of the swelling phenomenon as being caused by water incorporation. The model and methodology developed in this paper can be used to correlate electrochemical signatures with material chemical structure.

Srinivasan, Venkat; Bahne, C. Cornilsen; Weidner, John W.

2003-09-15T23:59:59.000Z

69

The FIT 2.0 Model - Fuel-cycle Integration and Tradeoffs  

SciTech Connect (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

70

A dynamic process model of a natural gas combined cycle -- Model development with startup and shutdown simulations  

SciTech Connect (OSTI)

Research in dynamic process simulation for integrated gasification combined cycles (IGCC) with carbon capture has been ongoing at the National Energy Technology Laboratory (NETL), culminating in a full operator training simulator (OTS) and immersive training simulator (ITS) for use in both operator training and research. A derivative work of the IGCC dynamic simulator has been a modification of the combined cycle section to more closely represent a typical natural gas fired combined cycle (NGCC). This paper describes the NGCC dynamic process model and highlights some of the simulator’s current capabilities through a particular startup and shutdown scenario.

Liese, Eric [U.S. DOE; Zitney, Stephen E. [U.S. DOE

2013-01-01T23:59:59.000Z

71

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  

SciTech Connect (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

72

Modeling the water-carbon-energy cycle | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challenge fundProject8Mistakes to Avoid MistakesResponse Times.Modeling

73

Modeling Energy Recovery Using Thermoelectric Conversion Integrated with an Organic Rankine Bottoming Cycle  

SciTech Connect (OSTI)

Hot engine exhaust represents a resource that is often rejected to the environment without further utilization. This resource is most prevalent in the transportation sector, but stationary engine-generator systems also typically do not utilize this resource. Engine exhaust is a source of high grade thermal energy that can potentially be utilized by various approaches to produce electricity or to drive heating and cooling systems. This paper describes a model system that employs thermoelectric conversion as a topping cycle integrated with an organic Rankine bottoming cycle for waste heat utilization. This approach is being developed to fully utilize the thermal energy contained in hot exhaust streams. The model is composed of a high temperature heat exchanger which extracts thermal energy for driving the thermoelectric conversion elements. However, substantial sensible heat remains in the exhaust stream after emerging from the heat exchanger. The model incorporates a closely integrated bottoming cycle to utilize this remaining thermal energy in the exhaust stream. The model has many interacting parameters that define combined system quantities such as overall output power, efficiency, and total energy utilization factors. In addition, the model identifies a maximum power operating point for the system. That is, the model can identify the optimal amount of heat to remove from the exhaust flow to run through the thermoelectric elements. Removing too much or too little heat from the exhaust stream in this stage will reduce overall cycle performance. The model has been developed such that heat exchanger UAh values, thermal resistances, ZT values, and multiple thermoelectric elements can be investigated in the context of system operation. The model also has the ability to simultaneously determine the effect of each cycle design parameter on the performance of the overall system, thus giving the ability to utilize as much waste heat as possible. Key analysis results are presented showing the impact of critical design parameters on power output, system performance and inter-relationships between design parameters in governing performance.

Miller, Erik W.; Hendricks, Terry J.; Peterson, Richard B.

2009-07-01T23:59:59.000Z

74

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

75

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

76

Global Biogeochemistry Models and Global Carbon Cycle Research at Lawrence Livermore National Laboratory  

SciTech Connect (OSTI)

The climate modeling community has long envisioned an evolution from physical climate models to ''earth system'' models that include the effects of biology and chemistry, particularly those processes related to the global carbon cycle. The widely reproduced Box 3, Figure 1 from the 2001 IPCC Scientific Assessment schematically describes that evolution. The community generally accepts the premise that understanding and predicting global and regional climate change requires the inclusion of carbon cycle processes in models to fully simulate the feedbacks between the climate system and the carbon cycle. Moreover, models will ultimately be employed to predict atmospheric concentrations of CO{sub 2} and other greenhouse gases as a function of anthropogenic and natural processes, such as industrial emissions, terrestrial carbon fixation, sequestration, land use patterns, etc. Nevertheless, the development of coupled climate-carbon models with demonstrable quantitative skill will require a significant amount of effort and time to understand and validate their behavior at both the process level and as integrated systems. It is important to consider objectively whether the currently proposed strategies to develop and validate earth system models are optimal, or even sufficient, and whether alternative strategies should be pursued. Carbon-climate models are going to be complex, with the carbon cycle strongly interacting with many other components. Off-line process validation will be insufficient. As was found in coupled atmosphere-ocean GCMs, feedbacks between model components can amplify small errors and uncertainties in one process to produce large biases in the simulated climate. The persistent tropical western Pacific Ocean ''double ITCZ'' and upper troposphere ''cold pole'' problems are examples. Finding and fixing similar types of problems in coupled carbon-climate models especially will be difficult, given the lack of observations required for diagnosis and validation of biogeochemical processes.

Covey, C; Caldeira, K; Guilderson, T; Cameron-Smith, P; Govindasamy, B; Swanston, C; Wickett, M; Mirin, A; Bader, D

2005-05-27T23:59:59.000Z

77

MODELLING RADIATIVELY ACTIVE WATER-ICE CLOUDS: IMPACT ON THE THERMAL STRUCTURE AND WATER CYCLE.  

E-Print Network [OSTI]

MODELLING RADIATIVELY ACTIVE WATER-ICE CLOUDS: IMPACT ON THE THERMAL STRUCTURE AND WATER CYCLE. J. The essential role of water-ice clouds in shaping the thermal structure of the martian atmosphere has been long presumed [1] but neglected in GCMs because of the lack of observations and difficulty to predict

Madeleine, Jean-Baptiste

78

Monitoring Forest Carbon Sequestration with Remote Sensing and Carbon Cycle Modeling  

E-Print Network [OSTI]

America, forest carbon sinks are be- lieved to offset a significant proportion of carbon emis- sionsMonitoring Forest Carbon Sequestration with Remote Sensing and Carbon Cycle Modeling DAVID P University Corvallis, Oregon 97331-5752, USA ABSTRACT / Sources and sinks of carbon associated with forests

Lefsky, Michael

79

Ecological Modelling 174 (2004) 6784 Fuzzy pattern recognition of circadian cycles in ecosystems  

E-Print Network [OSTI]

Ecological Modelling 174 (2004) 67­84 Fuzzy pattern recognition of circadian cycles in ecosystems S: Pattern recognition; Decision support systems; Fuzzy systems; Eutrophication; Phytoplankton; Wastewater pattern recognition techniques. The algorithm is organised in three parts: in the first, typical patterns

80

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

E-Print Network [OSTI]

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

Yang, Maria

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

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

E-Print Network [OSTI]

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

Frey, H. Christopher

82

Modeling the dynamics of human hair cycles by a follicular automaton  

E-Print Network [OSTI]

Modeling the dynamics of human hair cycles by a follicular automaton J. Halloy*, B. A. Bernard , G University of Brussels, Brussels, Belgium, May 15, 2000 (received for review December 23, 1999) The hair correspond, respectively, to hair growth, arrest, shedding, and absence before a new anagen phase

Goldbeter, Albert

83

From Modelica Models to Fault Diagnosis in Air Handling Units Raymond Sterling1  

E-Print Network [OSTI]

From Modelica Models to Fault Diagnosis in Air Handling Units Raymond Sterling1 , Peter Struss2 Handling Unit (AHU). This solution is derived from a general first-principle Modelica model and exploits 4 presents the modelica models and its calibration. In section 5 an example of the complete tool

Cengarle, María Victoria

84

A model of the VU (volume-unit) meter, with speech applications Bryce Lobdell  

E-Print Network [OSTI]

A model of the VU (volume-unit) meter, with speech applications Bryce Lobdell Jont Allen Beckman Institute, University of Illinois Urbana, IL 61801 (October 11, 2006) Running title: volume unit meter usage ABSTRACT The Volume Unit (VU) meter, used in speech research prior to the ad- vent of computers and modern

Allen, Jont

85

Marine geochemical data assimilation in an efficient Earth System Model of global biogeochemical cycling  

E-Print Network [OSTI]

Abstract. We have extended the 3-D ocean based “Grid ENabled Integrated Earth system model ” (GENIE-1) to help understand the role of ocean biogeochemistry and marine sediments in the long-term (?100 to 100 000 year) regulation of atmospheric CO2, and the importance of feedbacks between CO2 and climate. Here we describe the ocean carbon cycle, which in its first incarnation is based around a simple single nutrient (phosphate) control on biological productivity. The addition of calcium carbonate preservation in deep-sea sediments and its role in regulating atmospheric CO2 is presented elsewhere (Ridgwell and Hargreaves, 2007). We have calibrated the model parameters controlling ocean carbon cycling in GENIE-1 by assimilating 3-D observational datasets of phosphate and alkalinity using an ensemble Kalman filter method. The calibrated (mean) model predicts

A. Ridgwell; J. C. Hargreaves; N. R. Edwards; J. D. Annan; T. M. Lenton; R. Marsh; A. Yool; A. Watson

2006-01-01T23:59:59.000Z

86

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

E-Print Network [OSTI]

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

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

2015-01-01T23:59:59.000Z

87

Dose-Response Modeling for Life Cycle Impact Assessment: Findingsof the Portland Review Workshop  

SciTech Connect (OSTI)

The United Nations Environment Program (UNEP)/SETAC Life Cycle Initiative aims at putting life cycle thinking into practice and at improving the supporting tools for this process through better data and indicators. The initiative has thus launched three programs with associated working groups (see http://www.uneptie.org/pc/sustain/lcinitiative/). The Task Force on Toxic Impacts was established under the Life Cycle Impact Assessment (LCIA) program to establish recommended practice and guidance for use in human toxicity, ecosystem toxicity, and related categories with direct effects on human health and ecosystem health. The workshop consisted of three elements. (A) presentations summarizing (1) the goals of the LCIA Task Force (2) historical approaches to exposure and toxic impacts in LCIA (3) current alternative proposals for addressing human health impacts. Viewgraphs from two of these presentations are provided in Appendix B to this report. (B) Discussion among a panel of experts about the scientific defensibility of these historical and proposed approaches in the context of the goals of the LCIA Task Force 3 on toxicity impacts. (C) Development of the recommendations to the LCIA program and working group for optimum short- and long-term strategies for addressing human health impacts in LCA.

McKone, Thomas E.; Kyle, Amy D.; Jolliet, Olivier; Olsen, StigIrving; Hauschild, Michael

2006-06-01T23:59:59.000Z

88

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

SciTech Connect (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

89

AREA Units Units Units Management 220A Bldg Information Modeling, Katz 3 220A* Bldg Information Modeling, Katz 3 220A* Bldg Information Modeling, Katz 3  

E-Print Network [OSTI]

3 220C Advanced Building Information Modeling II, Katz 3 222A #$ Computer Integrated A/E/C, Fruchter, Benson 1 256 Building Systems, Kolderup 4 226E Energy Efficient Builiding Design, Rumsey 2,3 301 Energy 241A Infrastructure Project Development, Griggs 3 220B Advanced Building Information Modeling I, Katz

Prinz, Friedrich B.

90

Power Plant Cycling Costs  

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

(say, a trip) and such factors are not fully captured in this dataset. 9. Older combined cycle units were a step change in lower operating costs due to cycling...

91

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...

Yin, Peng

2011-10-21T23:59:59.000Z

92

Improved Swing-Cut Modeling for Planning and Scheduling of Oil-Refinery Distillation Units  

E-Print Network [OSTI]

, Pennsylvania 15213, United States. Crude-oil assays, Distillation, Fractionation, Swing-cuts, Temperature cut with in the nonlinear optimization. 1. INTRODUCTION Distillation or fractionation models for planning and scheduling1 Improved Swing-Cut Modeling for Planning and Scheduling of Oil-Refinery Distillation Units Brenno

Grossmann, Ignacio E.

93

Coupled Oscillator Model of the Business Cycle with Fluctuating Goods Markets  

E-Print Network [OSTI]

The sectoral synchronization observed for the Japanese business cycle in the Indices of Industrial Production data is an example of synchronization. The stability of this synchronization under a shock, e.g., fluctuation of supply or demand, is a matter of interest in physics and economics. We consider an economic system made up of industry sectors and goods markets in order to analyze the sectoral synchronization observed for the Japanese business cycle. A coupled oscillator model that exhibits synchronization is developed based on the Kuramoto model with inertia by adding goods markets, and analytic solutions of the stationary state and the coupling strength are obtained. We simulate the effects on synchronization of a sectoral shock for systems with different price elasticities and the coupling strengths. Synchronization is reproduced as an equilibrium solution in a nearest neighbor graph. Analysis of the order parameters shows that the synchronization is stable for a finite elasticity, whereas the synchron...

Ikeda, Y; Fujiwara, Y; Iyetomi, H; Ogimoto, K; Souma, W; Yoshikawa, H

2011-01-01T23:59:59.000Z

94

SOLAR MAGNETIC ACTIVITY CYCLES, CORONAL POTENTIAL FIELD MODELS AND ERUPTION RATES  

SciTech Connect (OSTI)

We study the evolution of the observed photospheric magnetic field and the modeled global coronal magnetic field during the past 3 1/2 solar activity cycles observed since the mid-1970s. We use synoptic magnetograms and extrapolated potential-field models based on longitudinal full-disk photospheric magnetograms from the National Solar Observatory's three magnetographs at Kitt Peak, the Synoptic Optical Long-term Investigations of the Sun vector spectro-magnetograph, the spectro-magnetograph and the 512-channel magnetograph instruments, and from Stanford University's Wilcox Solar Observatory. The associated multipole field components are used to study the dominant length scales and symmetries of the coronal field. Polar field changes are found to be well correlated with active fields over most of the period studied, except between 2003 and 2006 when the active fields did not produce significant polar field changes. Of the axisymmetric multipoles, only the dipole and octupole follow the poles whereas the higher orders follow the activity cycle. All non-axisymmetric multipole strengths are well correlated with the activity cycle. The tilt of the solar dipole is therefore almost entirely due to active-region fields. The axial dipole and octupole are the largest contributors to the global field except while the polar fields are reversing. This influence of the polar fields extends to modulating eruption rates. According to the Computer Aided CME Tracking, Solar Eruptive Event Detection System, and Nobeyama radioheliograph prominence eruption catalogs, the rate of solar eruptions is found to be systematically higher for active years between 2003 and 2012 than for those between 1997 and 2002. This behavior appears to be connected with the weakness of the late-cycle 23 polar fields as suggested by Luhmann. We see evidence that the process of cycle 24 field reversal is well advanced at both poles.

Petrie, G. J. D. [National Solar Observatory, Tucson, AZ 85719 (United States)

2013-05-10T23:59:59.000Z

95

La Spezia power plant: Conversion of units 1 and 2 to combined cycle with modification of steam turbines from cross compound to tandem compound  

SciTech Connect (OSTI)

Units 1 and 2 of ENEL's La Spezia power plant, rated 310 and 325 MW respectively, are going to be converted to combined cycle. This project will be accomplished by integrating components such as gas turbines and HRSGs with some of the existing components, particularly the steam turbines, which are of the cross compound type. Since the total power of each converted unit has to be kept at 335 MW because of permitting limitations, the power delivered by the steam turbine will be limited to about 115 MW. For this reason a study was carried out to verify the possibility of having only one shaft and modifying the turbine to tandem compound. As additional investments are required for this modification, a balance was performed that also took into account the incremental heat rate and, on the other hand, the benefits from decreased maintenance and increased availability and reliability calculated for the expected useful life. The result of this balance was in favor of the modification, and a decision was taken accordingly. The turbine modification will involve replacing the whole HP section with a new combined HP-IP section while retaining the corresponding LP rotor and cylinder and making the needed changes in the valve arrangements and piping. Work on the site began in the spring of 1997 by dismantling the existing boiler so as to have the space needed to install the GTs and HRSGs. The first synchronization of the converted unit 1 is scheduled for November 1999

Magneschi, P.; Gabiccini, S.; Bracaloni, N.; Fiaschi, C.

1998-07-01T23:59:59.000Z

96

Modeling California's high-elevation hydropower systems in energy units  

E-Print Network [OSTI]

conditions, hydropower provides 5­10% of the electricity used in the United States [National Energy Education it a valuable renewable energy source. In the mid-1990s, hydropower was about 19% of world's total electricity Development Project, 2007] and almost 75% of the nation's electricity from all renew- able sources [Energy

Pasternack, Gregory B.

97

Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model - 13413  

SciTech Connect (OSTI)

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. (authors)

Djokic, Denia [Department of Nuclear Engineering, University of California - Berkeley, 4149 Etcheverry Hall, Berkeley, CA 94720-1730 (United States)] [Department of Nuclear Engineering, University of California - Berkeley, 4149 Etcheverry Hall, Berkeley, CA 94720-1730 (United States); Piet, Steven J.; Pincock, Layne F.; Soelberg, Nick R. [Idaho National Laboratory - INL, 2525 North Fremont Avenue, Idaho Falls, ID 83415 (United States)] [Idaho National Laboratory - INL, 2525 North Fremont Avenue, Idaho Falls, ID 83415 (United States)

2013-07-01T23:59:59.000Z

98

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

SciTech Connect (OSTI)

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

99

Model Development Development of a system emulating the global carbon cycle in Earth system models  

E-Print Network [OSTI]

developed a loosely coupled model (LCM) which can represent the outputs of a GCMbased Earth system model

K. Tachiiri; J. C. Hargreaves; J. D. Annan; A. Oka; A. Abe-ouchi; M. Kawamiya

2010-01-01T23:59:59.000Z

100

A Three-Dimensional Ocean-Seaice-Carbon Cycle Model and its Coupling to a Two-Dimensional Atmospheric Model: Uses in Climate Change Studies  

E-Print Network [OSTI]

We describe the coupling of a three-dimensional ocean circulation model, with explicit thermodynamic seaice and ocean carbon cycle representations, to a two-dimensional atmospheric/land model. This coupled system has been ...

Dutkiewicz, Stephanie.

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

Hydrological Cycles over the Congo and Upper Blue Nile Basins: Evaluation of General Circulation Model Simulations and Reanalysis Products  

E-Print Network [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 Intergovernmental Panel ...

Demory, Marie-Estelle

102

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

103

Using Product Specific Simulation Models in a Tool for Manual Commissioning of Air Handling Units  

E-Print Network [OSTI]

This short paper describes an outline of a tool for manual commissioning of air handling units. The prototype tool is implemented EES professional version that can generate standalone programs. The idea is to use the benefit of simulation models...

Eriksson, J.

2003-01-01T23:59:59.000Z

104

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 (OSTI)

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

105

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

Energy Savers [EERE]

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...

106

MODELING THE DEMAND FOR E85 IN THE UNITED STATES  

SciTech Connect (OSTI)

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; Greene, David L [ORNL

2013-10-01T23:59:59.000Z

107

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

SciTech Connect (OSTI)

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

108

Framework for Modeling the Uncertainty of Future Events in Life Cycle Assessment  

E-Print Network [OSTI]

INTRODUCTION Life Cycle Assessment (LCA) is a leadingLife Cycle Assessment by including predictable disruptions to the life cycle, thereby increasing the meaningfulness of LCALife Cycle Assessment is a very important factor to consider in order to ensure the accuracy of estimated emissions and meaningfulness of LCA

Chen, Yi-Fen; Simon, Rachel; Dornfeld, David

2013-01-01T23:59:59.000Z

109

CBE UFAD cost analysis tool: Life cycle cost model, issues and assumptions  

E-Print Network [OSTI]

diffusers, underfloor fan coil units (FCU), etc. that arepurposes: VAV boxes and Fan Coil Units (FCU). Furthermore,

Webster, Tom; Benedek, Corinne; Bauman, Fred

2008-01-01T23:59:59.000Z

110

Modeling the Effects of Groundwater-fed Irrigation on Terrestrial Hydrology over the Conterminous United States  

SciTech Connect (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 terrestrial system, with potential impacts on weather and climate through land-atmosphere feedbacks. In this study, we incorporated a groundwater withdrawal scheme into the Community Land Model version 4 (CLM4). To simulate the impact of irrigation realistically, we calibrated the CLM4 simulated irrigation amount against observations from agriculture census at the county scale over the conterminous United States (CONUS). The water used for irrigation was then removed from the surface runoff and groundwater aquifer according to a ratio determined from the county-level agricultural census data. Based on the simulations, the impact of groundwater withdrawals for irrigation on land surface and subsurface fluxes were investigated. Our results suggest that the impacts of irrigation on latent heat flux and potential recharge when water is withdrawn from surface water alone or from both surface and groundwater are comparable and local to the irrigation areas. However, when water is withdrawn from groundwater for irrigation, greater effects on the subsurface water balance were found, leading to significant depletion of groundwater storage in regions with low recharge rate and high groundwater exploitation rate. Our results underscore the importance of local hydrologic feedbacks in governing hydrologic response to anthropogenic change in CLM4 and the need to more realistically simulate the two-way interactions among surface water, groundwater, and atmosphere to better understand the impacts of groundwater pumping on irrigation efficiency and climate.

Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Gao, Huilin; Leung, Lai-Yung R.

2014-06-01T23:59:59.000Z

111

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

SciTech Connect (OSTI)

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

112

Preliminary results of a dynamic system model for a closed-loop Brayton cycle coupled to a nuclear reactor.  

SciTech Connect (OSTI)

This paper describes preliminary results of a dynamic system model for a closed-loop Brayton-cycle that is coupled to a nuclear reactor. The current model assumes direct coupling between the reactor and the Brayton-cycle, however only minor additions are required to couple the Brayton-cycle through a heat exchanger to either a heat pipe reactor or a liquid metal cooled reactor. Few reactors have ever been coupled to closed Brayton-cycle systems. As such their behavior under dynamically varying loads, startup and shut down conditions, and requirements for safe and autonomous operation are largely unknown. Sandia National Laboratories has developed steady-state and dynamic models for closed-loop turbo-compressor systems (for space and terrestrial applications). These models are expected to provide a basic understanding of the dynamic behavior and stability of the coupled reactor and power generation loop. The model described in this paper is a lumped parameter model of the reactor, turbine, compressor, recuperator, radiator/waste-heat-rejection system and generator. More detailed models that remove the lumped parameter simplifications are also being developed but are not presented here. The initial results of the model indicate stable operation of the reactor-driven Brayton-cycle system and its ability to load-follow. However, the model also indicates some counter-intuitive behavior for the complete coupled system. This behavior will require the use of a reactor control system to select an appropriate reactor operating temperature that will optimize the performance of the complete spacecraft system. We expect this model and subsequent versions of it to provide crucial information in developing procedures for safe start up, shut down, safe-standby, and other autonomous operating modes. Ultimately, Sandia hopes to validate these models and to perform nuclear ground tests of reactor-driven closed Brayton-cycle systems in our nuclear research facilities.

Wright, Steven Alan

2003-06-01T23:59:59.000Z

113

The Role of Modeling in Clinical Information System Development Life-Cycle Mor Peleg, Department of Information Systems, University of Haifa, Haifa, Israel  

E-Print Network [OSTI]

The Role of Modeling in Clinical Information System Development Life-Cycle Mor Peleg, Department different stake holders. Conceptual modeling can play important roles in the development life-cycle. If these requirements are identified early in the development life-cycle then it is easier and more cost

Peleg, Mor

114

Simulated climatology of a general circulation model with a hydrological cycle  

E-Print Network [OSTI]

The thermal and dynamical structure of the tropical atmosphere which emerged from the numerical integration of our general circulation model with a simple hydrologic cycle is analyzed in detail. According to the results of our analysis, the lapse rate of zonal mean temperature in the model Tropics is supermoist-adiabatic in the lower troposphere, and is sub-moist-adiabatic above the 400-mb. level in qualitative agreement with thc observed features in the actual Tropics. The flow field in the model Tropics also displays interesting features. For example, a zone of strong convergence and a belt of heavy rain develops around the equator. Synoptic-scale disturbances such as weak tropical cyclones and shear lines with strong convergence develop and are reminiscent of disturbances in the actual tropical atmosphere. The humid towers, which result from moist convective adjustment and condensation, develop in the central core of the regions of strong upward motion, sometimes reaching the level of the tropical tropopause and thus heating the upper tropical troposphere. This heating compensates for thc cooling due to radiation and the meridional circulation. According to the analysis of the energy budget of the model Tropics, the release of eddy available potential energy, which is mainly generated by the heat of condensation, constitutes the major source of eddy kinetic energy of disturbances prevailing in the model Tropics.

Syukuro Manabe; Joseph Smagorinsky

1965-01-01T23:59:59.000Z

115

Categories and Functional Units: An Infinite Hierarchical Model for Brain Activations  

E-Print Network [OSTI]

Categories and Functional Units: An Infinite Hierarchical Model for Brain Activations Danial present a model that describes the structure in the responses of different brain areas to a set of stimuli encodes the relationship between brain activations and fMRI time courses. A variational inference

Golland, Polina

116

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

117

Global Climate Modeling of the Martian water cycle with improved microphysics and radiatively active water ice clouds  

E-Print Network [OSTI]

Radiative effects of water ice clouds have noteworthy consequences on the Martian atmosphere, its thermal structure and circulation. Accordingly, the inclusion of such effects in the LMD Mars Global Climate Model (GCM) greatly modifies the simulated Martian water cycle. The intent of this paper is to address the impact of radiatively active clouds on atmospheric water vapor and ice in the GCM and improve its representation. We propose a new enhanced modeling of the water cycle, consisting of detailed cloud microphysics with dynamic condensation nuclei and a better implementation of perennial surface water ice. This physical modeling is based on tunable parameters. This new version of the GCM is compared to the Thermal Emission Spectrometer observations of the water cycle. Satisfying results are reached for both vapor and cloud opacities. However, simulations yield a lack of water vapor in the tropics after Ls=180{\\deg} which is persistent in simulations compared to observations, as a consequence of aphelion c...

Navarro, Thomas; Forget, François; Spiga, Aymeric; Millour, Ehouarn; Montmessin, Franck

2013-01-01T23:59:59.000Z

118

Model for cradle-to-gate life cycle assessment of clinker production  

SciTech Connect (OSTI)

A model for input- and technology-dependent cradle-to-gate life cycle assessments (LCA) was constructed to quantify emissions and resource consumption of various clinker production options. The model was compiled using data of more than 100 clinker production lines and complemented with literature data and best judgment from experts. It can be applied by the cement industry for the selection of alternative fuels and raw materials (AFR) and by authorities for decision-support regarding the permission of waste co-processing in cement kilns. In the field of sustainable construction, the model can be used to compare clinker production options. Two case studies are presented. First, co-processing of four different types of waste is analyzed at a modern precalciner kiln system. Second, clinker production is compared between five kiln systems. Results show that the use of waste (tires, prepared industrial waste, dried sewage sludge, blast furnace slag) led to reduced greenhouse gas emissions, decreased resource consumption, and mostly to reduced aggregated environmental impacts. Regarding the different kiln systems, the environmental impact generally increased with decreasing energy efficiency. 35 refs., 2 figs., 2 tabs.

Michael Elias Boesch; Annette Koehler; Stefanie Hellweg [ETH Zurich, Zurich (Switzerland). Institute of Environmental Engineering

2009-10-01T23:59:59.000Z

119

Stirling-cycle refrigerator  

SciTech Connect (OSTI)

A Stirling-cycle refrigerator comprises a plurality of Stirling-cycle refrigerator units each having a displacer defining an expansion chamber, a piston defining a compression chamber, and a circuit including a heater and a cooler and interconnecting the expansion chamber and the compression chamber, and a heat exchanger shared by the circuits and disposed between the coolers and the heaters for effecting heat exchange between working gases in the circuits. The heat exchanger may comprise a countercurrent heat exchanger, and the Stirling-cycle refrigerator units are operated in cycles which are 180/sup 0/ out of phase with each other.

Nakamura, K.

1985-06-11T23:59:59.000Z

120

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

SciTech Connect (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

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

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

E-Print Network [OSTI]

Evaluation of the Daylight Cycle of Model-Predicted Cloud Amount and Condensed Water Path over accurate information on diurnal cycles during daylight hours of cloud properties over land and ocean surfaces. This paper evaluates the daylight cycle of CA and CWP as predicted by the Regional Atmospheric

Stoffelen, Ad

122

Cyclus fuel cycle simulation capabilities with the CYDER disposal system model  

SciTech Connect (OSTI)

An algorithm and supporting database for rapid thermal repository loading calculation was implemented in CYDER. This algorithm employs a Specific Temperature Change (STC) method and has resulted from combining detailed spent nuclear fuel composition data with a detailed thermal repository performance analysis tool from Lawrence Livermore National Laboratory (LLNL), Argonne National Laboratory (ANL), and the Used Fuel Disposition (UFD) campaign. By abstraction of and benchmarking against these detailed thermal models, CYDER captures the dominant physics of thermal phenomena affecting repository capacity in various geologic media and as a function of spent fuel composition. Abstraction based on detailed computational thermal repository performance calculations with the LLNL semi-analytic model has resulted in implementation of the STC estimation algorithm and a supporting reference dataset. This method is capable of rapid estimation of temperature increase near emplacement tunnels as a function of waste composition, limiting radius, waste package spacing, near field thermal conductivity and near field thermal diffusivity. The sensitivity analyses and validation efforts conducted in this work demonstrate the capability of the CYDER tool to provide repository capacity and performance metrics in the context of dynamic fuel cycle.

Huff, K.D. [Argonne National Laboratory, 9700 S. Cass Ave., Lemont, IL 60439 (United States); University of Wisconsin, 1500 Engineering Drive, Madison, WI 53706 (United States)

2013-07-01T23:59:59.000Z

123

Utero-fetal unit and pregnant woman modeling using a computer graphics approach for  

E-Print Network [OSTI]

Utero-fetal unit and pregnant woman modeling using a computer graphics approach for dosimetry for fetuses during pregnancy. Human fetus exposure can only be assessed through simulated dosimetry studies performed in vivo on animals and in vitro at the cellular level are complemented by simulated dosimetry

Boubekeur, Tamy

124

Seismic modelling of a fractured carbonate reservoir in Abu Dhabi, United Arab Emirates  

E-Print Network [OSTI]

Seismic modelling of a fractured carbonate reservoir in Abu Dhabi, United Arab Emirates Mohammed Y is required to optimize hydrocarbon production. A rock containing parallel fractures can be seismically to the seismic wavelength. Seismic anisotropy may be detectable from attributes of pre-stack 3-D seismic data

Ali, Mohammed

125

Development of models for series and parallel fan variable air volume terminal units  

E-Print Network [OSTI]

for the series and parallel units, with coefficients varying by size and manufacturer. Statistical modeling utilized SAS software (2002). Fan power and airflow data were collected at downstream static pressures over a range from 0.1 to 0.5 in. w.g. (25 to 125 Pa...

Furr, James C., Jr

2007-09-17T23:59:59.000Z

126

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

SciTech Connect (OSTI)

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

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

2005-09-01T23:59:59.000Z

127

Stabilization of a Three-Dimensional Limit Cycle Walking Model through Step-to-Step Ankle Control  

E-Print Network [OSTI]

Stabilization of a Three-Dimensional Limit Cycle Walking Model through Step-to-Step Ankle Control ankle control. If ankle control can contribute significantly to maintaining balance, even in the presence of active foot placement, this might provide an opportunity to improve balance using robotic ankle

Collins, Steven H.

128

Peatland carbon cycle responses to hydrological change at time scales from years to centuries: Impacts on model  

E-Print Network [OSTI]

Peatland carbon cycle responses to hydrological change at time scales from years to centuries: Impacts on model simulations and regional carbon budgets By Benjamin N. Sulman A dissertation submitted to the long-term storage of carbon in peat, these ecosystems contain a significant fraction of the global

Wisconsin at Madison, University of

129

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.

130

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

SciTech Connect (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

131

A Preliminary and Simplified Closed Brayton Cycle Modeling for a Space Reactor Application  

SciTech Connect (OSTI)

The Nuclear Energy Division (ENU) of the Institute for Advanced Studies (IEAv) has started a preliminary design study for a Closed Brayton Cycle Loop (CBCL) aimed at a space reactor application. The main objectives of the study are: 1) to establish a starting concept for the CBCL components specifications, and 2) to build a demonstrative simulator of CBCL. This preliminary design study is developing the CBCL around the NOELLE 60290 turbo machine. The actual nuclear reactor study is being conducted independently. Because of that, a conventional heat source is being used for the CBCL, in this preliminary design phase. This paper describes the steady state simulator of the CBCL operating with NOELLE 60290 turbo machine. In principle, several gases are being considered as working fluid, as for instance: air, helium, nitrogen, CO{sub 2} and gas mixtures such as helium and xenon. However, for this first application pure helium will be used as working fluid. Simplified models of heat and mass transfer were developed to simulate thermal components. Future efforts will focus on implementing a graphical interface to display the thermal process variables in steady state and to keep track of the modifications being implemented at the NOELLE 60290 turbo machine in order to build the CBCL.

Guimaraes, Lamartine Nogueira Frutuoso; Camillo, Giannino Ponchio [Institute for Advanced Studies, Rodovia dos Tamoios, km 5.5, Putim, 12228-001, Sao Jose dos Campos, SP (Brazil)

2008-01-21T23:59:59.000Z

132

Calibration of Reduced Dynamic Models of Power Systems using Phasor Measurement Unit (PMU) Data  

SciTech Connect (OSTI)

Accuracy of a power system dynamic model is essential to the secure and efficient operation of the system. Lower confidence on model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, identification algorithms have been developed to calibrate parameters of individual components using measurement data from staged tests. To facilitate online dynamic studies for large power system interconnections, this paper proposes a model reduction and calibration approach using phasor measurement unit (PMU) data. First, a model reduction method is used to reduce the number of dynamic components. Then, a calibration algorithm is developed to estimate parameters of the reduced model. This approach will help to maintain an accurate dynamic model suitable for online dynamic studies. The performance of the proposed method is verified through simulation studies.

Zhou, Ning; Lu, Shuai; Singh, Ruchi; Elizondo, Marcelo A.

2011-09-23T23:59:59.000Z

133

Development and Use of Baseline Monthly Utility Models for Eight Army Installations Around the United States  

E-Print Network [OSTI]

3/96-Final Report, p. i ESL-TR-96/03-01 DEVELOPMENT AND USE OF BASELINE MONTHLY UTILITY MODELS FOR EIGHT ARMY INSTALLATIONS AROUND THE UNITED STATES Prepared by: T.A. Reddy, N.F. Saman, D.E. Claridge, J.S. Haberl and W.D. Turner Research Sponsored... and Scope 2 2.1 Objectives 2 2.2 Data provided 3 2.3 Scope of study 7 3.0 Mathematical Basis of Regression Models 8 3.1 Pertinent background 8 3.2 Simple regression models using Emodel 9 3.3 Generation of 95% uncertainty bands for individual months 14 3...

Reddy, T. A.; Saman, N. F.; Claridge, D. E.; Haberl, J. S.; Turner, W. D.

1996-01-01T23:59:59.000Z

134

Generated using version 3.1.2 of the official AMS LATEX template A Heuristic Model of Dansgaard-Oeschger Cycles: Description,1  

E-Print Network [OSTI]

-layer sea ice model9 with an energy-balance atmosphere. Parameterizations are included for offshore poly for studying the D-O cycles of the last glacial period,7 based on the Nordic Ice Machine hypothesis presented~nya10 activity and sea ice export from the column. The resulting heuristic model was found to11 cycle

Battisti, David

135

The need for a characteristics-based approach to radioactive waste classification as informed by advanced nuclear fuel cycles using the fuel-cycle integration and tradeoffs (FIT) model  

SciTech Connect (OSTI)

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. Because heat generation is generally the most important factor limiting geological repository areal loading, 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. Waste streams generated in different fuel cycles and their possible classification based on the current U.S. framework and international standards are discussed. It is shown that the effects of separating waste streams are neglected under a source-based radioactive waste classification system. (authors)

Djokic, D. [Department of Nuclear Engineering, University of California, Berkeley, 3115B Etcheverry Hall, Berkeley, CA 94720-1730 (United States); Piet, S.; Pincock, L.; Soelberg, N. [Idaho National Laboratory - INL, 2525 North Fremont Avenue, Idaho Falls, ID 83415 (United States)

2013-07-01T23:59:59.000Z

136

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

SciTech Connect (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

137

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

138

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

SciTech Connect (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] [ORNL; Rice, C Keith [ORNL] [ORNL; Vineyard, Edward [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL)

2013-01-01T23:59:59.000Z

139

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 (OSTI)

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

140

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

E-Print Network [OSTI]

precipitation, the impacts of climate change on vegetation and water cycle are predicted with relatively low under Climate Change Scenarios* PABLO IMBACH,1 LUIS MOLINA,1 BRUNO LOCATELLI,# OLIVIER ROUPSARD,1,@ GIL MAHE´ ,& RONALD NEILSON,**,&& LENIN CORRALES,11 MARKO SCHOLZE,## AND PHILIPPE CIAIS @@ 1 Climate Change

Boyer, Edmond

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

Modeling and experimental results for condensing supercritical CO2 power cycles.  

SciTech Connect (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

142

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

SciTech Connect (OSTI)

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

143

A model of the VU (volume-unit) meter, with speech applications Bryce E. Lobdell and Jont B. Allen  

E-Print Network [OSTI]

A model of the VU (volume-unit) meter, with speech applications Bryce E. Lobdell and Jont B. Allen October 2006; accepted 12 October 2006 The Volume-Unit VU meter, used in speech research prior. There are no known software implementations of this meter, which meet the 1954 ASA standard and provide

Allen, Jont

144

Model-Based Testing of Automotive Electronic Control Units Ghmann, Clemens {clemens.guehmann@tu-berlin.de}  

E-Print Network [OSTI]

Model-Based Testing of Automotive Electronic Control Units Gühmann, Clemens {clemens.guehmann@tu-berlin.de} Technische Universität Berlin, Department of Electronic Measurement and Diagnostic Technology Einsteinufer 17 by networking electronic control units (ECUs), and by implementation of the functions distributed throughout

Wichmann, Felix

145

United: How one computer model makes Texas surface water management possible  

E-Print Network [OSTI]

Story by Leslie Lee Summer 2013 tx H2O 3 Photo by Kathleen Phillips, Texas A&M AgriLife UNITED How one computer model makes Texas surface water management possible Managing surface water supplies in Texas is complex, to say the least. Multiple... of conditions. W#15;P enables surface water managers throughout Texas to allocate water resources, plan for the future and ensure there is enough water for environmental as well as human needs. A statewide surface water permitting system is born Prior...

Lee, Leslie

2013-01-01T23:59:59.000Z

146

Energy policy modeling: United States and Canadian experiences. Volume I. Specialized energy policy models  

SciTech Connect (OSTI)

The Canadian Energy Policy Modeling Conference held in North Vancouver, May 18-20, 1978, was organized to assess the state of the art in energy modeling in North America. A major aim of the conference was to determine the extent to which energy modeling had and could make a contribution to the energy-policy decision-making process. Two volumes contain revised and updated versions of the major papers presented at the conference plus edited transcripts of the panel discussions and several additional papers aimed at particular topics deemed worthy of further study. This volume, Vol. I, is concerned with specialized models and contains the following sections: (a) Energy Demand Modeling (7 papers); (b) Energy Supply Modeling (5 papers); (c) Coal and Transportation Modeling (6 papers); and (d) Problems and Interactions of Energy, Environment, and Conservation (4 papers). A separate abstract was prepared for each of the 22 papers for Energy Abstracts for Policy Analysis (EAPA); 5 abstracts will appear in Energy Research Abstracts (ERA).

Ziemba, W.T.; Schwartz, S.L.; Koenigsberg, E. (eds.)

1980-01-01T23:59:59.000Z

147

Federal Register Notice for Life Cycle Greenhouse Gas Perspective...  

Energy Savers [EERE]

Federal Register Notice for Life Cycle Greenhouse Gas Perspective on Exporting Liquefied Natural Gas from the United States Federal Register Notice for Life Cycle Greenhouse Gas...

148

Implications of changing natural gas prices in the United States electricity sector for SO2, NOX and life cycle GHG emissions: Supplementary Information  

E-Print Network [OSTI]

/MJ = 59 kg CO2 e/MWh Combustion emissions at natural gas plant A in ERCOT: 500 kg CO2 e/MWh Annual = 59 kg CO2 e/MWh / 40% = 148 kg CO2 e/MWh Combustion emissions per MWh = 500 kg CO2 e/MWh Life cycle-level combustion emissions at fossil fuel plants in ERCOT, MISO and PJM. The red lines represent median values

Jaramillo, Paulina

149

Energy policy modeling: United States and Canadian experiences. Volume II. Integrative energy policy models  

SciTech Connect (OSTI)

The Canadian Energy Policy Modeling Conference, held in North Vancouver, May 18-20, 1978, was organized to assess the state of the art in energy modeling in North America. A major aim of the conference was to determine the extent to which energy modeling had and could make a contribution to the energy-policy decision-making process. Two volumes contain revised and updated versions of the major papers presented at the conference plus edited transcripts of the panel discussions and several additional papers aimed at particular topics deemed worthy of further study. For this volume, Vol. II, a separate abstract was prepared for each of 17 papers, 2 panel discussions, and three session-introduction commentaries for Energy Abstracts for Policy Analysis (EAPA); 7 abstracts will appear in Energy Research Abstracts (ERA).

Ziemba, W.T.; Schwartz, S.L. (eds.)

1980-01-01T23:59:59.000Z

150

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

SciTech Connect (OSTI)

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

Smith, F.

2012-08-06T23:59:59.000Z

151

A full field model study of the East Velma West Block Sims Sand Unit reservoir  

SciTech Connect (OSTI)

A full-field numerical model of the East Velma West Block Sims Sand Unit (EVWBSSU) reservoir was developed. From the history-matched model, field performance predictions were made for continued waterflood and various operating scenarios under the present CO/sub 2/ injection scheme. Results include the effect of CO/sub 2/ pipeline supply rate, allocation of CO/sub 2/ and water to injection wells, and uncertain parameters on reservoir performance. From these projections it was concluded that the amount of injected CO/sub 2/ required to produce an incremental barrel of oil over waterflood was not strongly dependent on CO/sub 2/ pipeline supply rate or allocation of injected fluids to injection wells. This conclusion seems reasonable mechanistically because the miscible displacement was dominated by gravity, the areal variation in predicted updip oil saturation was not great, and the continuous injection coupled with high permeability updip caused uniform distribution of CO/sub 2/.

Bolling, J.D.

1985-08-01T23:59:59.000Z

152

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

SciTech Connect (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

153

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

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

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

154

A PROBABILISTIC TWO-SCALE MODEL FOR HIGH CYCLE FATIGUE LIFE PREDICTIONS  

E-Print Network [OSTI]

volumes of a dual-phase steel. Keywords Fatigue limits; Weibull model; Microplasticity; Thermomechanics. 1

155

Unit physics performance of a mix model in Eulerian fluid computations  

SciTech Connect (OSTI)

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

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

2011-01-25T23:59:59.000Z

156

Modeling of Electronically Commutated Motor Controlled Fan-powered Terminal Units  

E-Print Network [OSTI]

Feet Per Minute ECM Electronically Commutated Motor FPTU Fan Powered Terminal Unit Pdown Downstream Static Pressure PF Power Factor Pup Upstream Static Pressure SCR Silicon Controlled Rectifier THD Total Harmonic Distortion VAV Variable Air... parallel unit pressurizes the FPTU causing some of the primary air to leak out of the unit. Another difference between them is that series terminal units allow the primary air system to operate at a lower static pressure because the terminal unit fan...

Edmondson, Jacob Lee

2011-02-22T23:59:59.000Z

157

Modeling Approach/Strategy for Corrective Action Unit 97, Yucca Flat and Climax Mine , Revision 0  

SciTech Connect (OSTI)

The objectives of the UGTA corrective action strategy are to predict the location of the contaminant boundary for each CAU, develop and implement a corrective action, and close each CAU. The process for achieving this strategy includes modeling to define the maximum extent of contaminant transport within a specified time frame. Modeling is a method of forecasting how the hydrogeologic system, including the underground test cavities, will behave over time with the goal of assessing the migration of radionuclides away from the cavities and chimneys. Use of flow and transport models to achieve the objectives of the corrective action strategy is specified in the FFACO. In the Yucca Flat/Climax Mine system, radionuclide migration will be governed by releases from the cavities and chimneys, and transport in alluvial aquifers, fractured and partially fractured volcanic rock aquifers and aquitards, the carbonate aquifers, and in intrusive units. Additional complexity is associated with multiple faults in Yucca Flat and the need to consider reactive transport mechanisms that both reduce and enhance the mobility of radionuclides. A summary of the data and information that form the technical basis for the model is provided in this document.

Janet Willie

2003-08-01T23:59:59.000Z

158

The Tiffany Unit N2 - ECBM Pilot: A Reservoir Modeling Study  

SciTech Connect (OSTI)

In October, 2000, the U.S. Department of Energy, through contractor Advanced Resources International, launched a multi-year government-industry R&D collaboration called the Coal-Seq project. The Coal-Seq project is investigating the feasibility of CO{sub 2} sequestration in deep, unmineable coalseams, by performing detailed reservoir studies of two enhanced coalbed methane recovery (ECBM) 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 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 multi-component 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 Tiffany Unit reservoir modeling study. The Tiffany Unit is located in the northern portion of the prolific San Juan basin (in Southern Colorado). The study area consists of 34 methane production wells and 12 nitrogen injection wells. The field originally began production in 1983, and N{sub 2} injection operations for ECBM purposes commenced in 1998. Nitrogen injection was suspended in 2002, 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 COMET3 reservoir simulator, and future field performance was forecast under various operating conditions. Based on the results of the study, the following major conclusions have been drawn: (1) The injection of N{sub 2} at the Tiffany Unit has resulted in incremental methane recovery over estimated primary recovery, in approximate proportion of one volume of methane for every 0.4 volumes of injected nitrogen on a net basis. In the swept areas, an incremental methane recovery of approximately 20% of original-gas-in-place resulted from N{sub 2}-ECBM operations. (2) At the prevailing gas prices at the time the project was implemented ({approx}2.20/Mcf), and not considering any tax credit benefits, the pilot itself was uneconomic. However, with today's gas prices of {approx}$4.00/Mcf, N{sub 2}-ECBM appears economically attractive. (3) Performance predictions of future injection suggests CO{sub 2} sequestration can be accomplished at a slight profit. Economic performance is enhanced by adding some N{sub 2} to the injectant.

Scott Reeves; Anne Oudinot

2004-03-31T23:59:59.000Z

159

An activity-based-parametric hybrid cost model to estimate the unit cost of a novel gas turbine component  

E-Print Network [OSTI]

An activity-based-parametric hybrid cost model to estimate the unit cost of a novel gas turbine in gas turbine compressors. However, the model disc (blisk) designs which are used by the aerospace industry in gas turbine compressors. The tool

Sóbester, András

160

Financing Strategies for Nuclear Fuel Cycle Facility  

SciTech Connect (OSTI)

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

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

Electronic Structure Description of the Cis-MoOS Unit in Models for Molybdenum Hydroxylases  

SciTech Connect (OSTI)

The molybdenum hydroxylases catalyze the oxidation of numerous aromatic heterocycles and simple organics and, unlike other hydroxylases, utilize water as the source of oxygen incorporated into the product. The electronic structures of the cis-MoOS units in CoCp{sub 2}[Tp{sup iPr}Mo{sup V}OS(OPh)] and Tp{sup iPr}Mo{sup VI}OS(OPh) (Tp{sup iPr} = hydrotris(3-isopropylpyrazol-1-yl)borate), new models for molybdenum hydroxylases, have been studied in detail using S K-edge X-ray absorption spectroscopy, vibrational spectroscopy, and detailed bonding calculations. The results show a highly delocalized Mo {double_bond} S {pi}* LUMO redox orbital that is formally Mo(d{sub xy}) with {approx}35% sulfido ligand character. Vibrational spectroscopy has been used to quantitate Mo-S{sub sulfido} bond order changes in the cis-MoOS units as a function of redox state. Results support a redox active molecular orbital that has a profound influence on MoOS bonding through changes to the relative electro/nucleophilicity of the terminal sulfido ligand accompanying oxidation state changes. The bonding description for these model cis-MoOS systems supports enzyme mechanisms that are under orbital control and dominantly influenced by the unique electronic structure of the cis-MoOS site. The electronic structure of the oxidized enzyme site is postulated to play a role in polarizing a substrate carbon center for nucleophilic attack by metal activated water and acting as an electron sink in the two-electron oxidation of substrates.

Doonan, C.J.; Rubie, N.D.; Peariso, K.; Harris, H.H.; Knottenbelt, S.Z.; George, G.N.; Young, C.G.; Kirk, M.L.; /New Mexico U. /Melbourne U. /SLAC, SSRL

2009-04-29T23:59:59.000Z

162

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

SciTech Connect (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

163

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

SciTech Connect (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, 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

164

Associative list processing unit  

DOE Patents [OSTI]

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.

Hemmert, Karl Scott; Underwood, Keith D

2014-04-01T23:59:59.000Z

165

Combined Cycle Combustion Turbines  

E-Print Network [OSTI]

Combined Cycle Combustion Turbines Steven Simmons February 27 2014 1 #12;CCCT Today's Discussion 1 Meeting Pricing of 4 advanced units using information from Gas Turbine World Other cost estimates from E E3 EIA Gas Turbine World California Energy Commission Date 2010 Oct 2012, Dec 2013 Apr 2013 2013 Apr

166

An integrated life cycle quality model for general public market software products  

E-Print Network [OSTI]

. The requirements are built upon existing industry standards, including ISO 9001. The TL 9000 Quality System quality view of TL9000 Handbook and detailed view from ISO/IEC 1926 in the process of defining, measuring by TL9000-ISO complement model as well as by application process walk-through. #12;1. Complement model

Laporte, Claude Y.

167

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

SciTech Connect (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

168

Virtuous Cycle Cycles of activity and software projects  

E-Print Network [OSTI]

Inspection #12;Programming Cycle - single bug Selected Bug Shared Code Fix Bug Continuous Integration ~8 cycle cvscheck compilation style checking testing javadocs documentation jumble quality of unit testing #12;NetValue Development cvscheck - Source Code Control and Build Shared Centralized Automatic

Pfahringer, Bernhard

169

Multimodal Model Integration for Sentence Unit Detection Electrical and Computer Engineering  

E-Print Network [OSTI]

of an idea unit, giving up the floor, fatigue); if we can bet- ter understand those reasons, our human

Shriberg, Elizabeth

170

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

SciTech Connect (OSTI)

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

171

Diurnal cycle of air pollution in the Kathmandu Valley, Nepal: 2. Modeling results  

E-Print Network [OSTI]

After completing a 9-month field experiment studying air pollution and meteorology in the Kathmandu Valley, Nepal, we set up the mesoscale meteorological model MM5 to simulate the Kathmandu Valley's meteorology with a ...

Panday, Arnico K.

172

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]

to the fluid-mechanical-magnetic processes associated with the cycle implementation. The interface between in MATLAB. The model uses cycle inputs such as the fluid mass flow and magnetic field profiles, fluid temperature profile of the fluid and regenerator. Using the temperature profiles, the cooling load produced

Wisconsin at Madison, University of

173

Generated using version 3.1.2 of the official AMS LATEX template A Heuristic Model of Dansgaard-Oeschger Cycles: Description,1  

E-Print Network [OSTI]

circulation are10 invoked. Parameterizations are included for latent heat poly~nyas and sea ice export from the D-O cycles of the last glacial period, based on7 the Dokken Nordic Ice Machine hypothesis. The model ice model with an9 energy-balance atmosphere; no changes in the large-scale ocean overturning

Battisti, David

174

Generated using version 3.1.2 of the official AMS LATEX template A Heuristic Model of Dansgaard-Oeschger Cycles: Description,1  

E-Print Network [OSTI]

circulation10 are invoked. Parameterizations are included for latent heat poly~nyas and sea ice export11 from the D-O cycles of the last glacial period, based on7 the Dokken Nordic Ice Machine hypothesis. The model ice model with9 an energy-balance atmosphere; no changes in the large-scale ocean overturning

Battisti, David

175

Regional climate effects of irrigation and urbanization in thewestern united states: a model intercomparison  

SciTech Connect (OSTI)

In the western United States, more than 30,500 square miles has been converted to irrigated agriculture and urban areas. This study compares the climate responses of four regional climate models (RCMs) to these past land-use changes. The RCMs used two contrasting land cover distributions: potential natural vegetation, and modern land cover that includes agriculture and urban areas. Three of the RCMs represented irrigation by supplementing soil moisture, producing large decreases in August mean (-2.5 F to -5.6 F) and maximum (-5.2 F to -10.1 F) 2-meter temperatures where natural vegetation was converted to irrigated agriculture. Conversion to irrigated agriculture also resulted in large increases in relative humidity (9 percent 36 percent absolute change). Only one of the RCMs produced increases in summer minimum temperature. Converting natural vegetation to urban land cover produced modest but discernable climate effects in all models, with the magnitude of the effects dependent upon the preexisting vegetation type. Overall, the RCM results indicate that land use change impacts are most pronounced during the summer months, when surface heating is strongest and differences in surface moisture between irrigated land and natural vegetation are largest. The irrigation effect on summer maximum temperatures is comparable in magnitude (but opposite in sign) to predicted future temperature change due to increasing greenhouse gas concentrations.

Snyder, M.A.; Kueppers, L.M.; Sloan, L.C.; Cavan, D.C.; Jin, J.; Kanamaru, H.; Miller, N.L.; Tyree, M.; Du, H.; Weare, B.

2006-05-01T23:59:59.000Z

176

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

177

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

SciTech Connect (OSTI)

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.

NONE

1996-12-01T23:59:59.000Z

178

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

SciTech Connect (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

179

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

SciTech Connect (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

180

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

SciTech Connect (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

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

An integrated life cycle quality model for general public market software products  

E-Print Network [OSTI]

. The requirements are built upon existing industry standards, including ISO 9001. The TL 9000 Quality System quality view of TL9000 Handbook and detailed view from ISO/IEC 1926 in the process of defining, measuring by TL9000-ISO complement model as well as by application process walk-through. Proceedings of Software

Suryn, Witold

182

A Heuristic Model of DansgaardOeschger Cycles. Part I: Description, Results, and Sensitivity Studies  

E-Print Network [OSTI]

. Parameterizations are included for latent heat polynyas and sea ice export from the column. The resulting heuristic representing the Nordic seas and is composed of ocean boxes stacked below a one-layer sea ice model in the proxy observational data, with the presence or absence of perennial sea ice in the Nordic seas being

Battisti, David

183

Life-cycle Assessment of Semiconductors  

E-Print Network [OSTI]

yield. A hybrid life cycle assessment (LCA) model is used;more accurate life-cycle assessment (LCA) of electronicthe purposes of life-cycle assessment (LCA). While it may be

Boyd, Sarah B.

2009-01-01T23:59:59.000Z

184

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

SciTech Connect (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] [ORNL

2012-01-01T23:59:59.000Z

185

Associative list processing unit  

DOE Patents [OSTI]

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

186

The behavior of a multidimensional rainfall model through an annual cycle in the Brazos Valley  

E-Print Network [OSTI]

rate of the storm is denoted by the parameter I. The number of bursts per storm ss identically and independently dkstrtbuted with a pa? eter nf v The depth assocsated wsth each burst is also identically and independently dkstributed with s, parameter... 01 min The density of cluster potential centers per rainband expressed in CPC's/km Range 0 01 to 0. 0001 into The rainfall intensity at the birth center and birth time of the raincell. In the exponential decay situation used in this model...

Koepsell, Royal Warren

1989-01-01T23:59:59.000Z

187

Fast and Informative Flow Simulations in a Building by Using Fast Fluid Dynamics Model on Graphics Processing Unit  

E-Print Network [OSTI]

Fast and Informative Flow Simulations in a Building by Using Fast Fluid Dynamics Model on Graphics solve Navier-Stokes equations and other transportation equations for energy and species at a speed of 50 it in parallel on a Graphics Processing Unit (GPU). This study validated the FFD on the GPU by simulating

Chen, Qingyan "Yan"

188

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

SciTech Connect (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

189

A metabolic model of the mitochondrion and its use in modelling diseases of the tricarboxylic acid cycle.  

E-Print Network [OSTI]

simulations were carried out in MATLAB (MathWorks, Inc., Natick, MA) using the COBRA toolbox [54] and the linear programming solver GLPK (http://www.gnu.org/software/glpk). Networks were visualised using Cytoscape [55]. All graphs were generated using... described in detail elsewhere [7,8], but briefly the main data required is a stoichiometric matrix (S), which represents all the reactions and metabolites in the model. The matrix is used with the assumption that the model is at a quasi steady state...

Smith, Anthony C; Robinson, Alan J

2011-06-29T23:59:59.000Z

190

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

191

Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks: results from an atmosphere-ocean general circulation model  

E-Print Network [OSTI]

2009 P. E. Thornton et al. : Carbon-nitrogen interactionsregulate climate-carbon cycle feedbacks Monfray, P. ,T. H. : A global ocean carbon climatology: Results from

2009-01-01T23:59:59.000Z

192

Field Test of Combined Desiccant-Evaporator Cycle Providing Lower Dew Points and Enhanced Dehumidification  

E-Print Network [OSTI]

1939 2262 2585 2908 3231 AmbientF AmbientRH Return F Return RH Figure 11. One Month MODEL C Operational Data. Set Points Are 76 F and 45 % RH. Each Data Point Represents A 15 Minute Average. The Fan Is Set on “Auto”, That Is, It Cycles On and Off... with the better humidistat. The MODEL C unit provided excellent humidity control at the 45% RH set point, with occasional overcooling at night of several degrees (when the building is unoccupied). No reheat was used. For control, the unit was cycled...

Cromer, C. J.

2006-01-01T23:59:59.000Z

193

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

SciTech Connect (OSTI)

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

194

MODELING, IDENTIFICATION AND CONTROL, 2006, VOL. 00, NO. 0, 000000 Control Design for a Gas Turbine Cycle with CO2 Capture  

E-Print Network [OSTI]

MODELING, IDENTIFICATION AND CONTROL, 2006, VOL. 00, NO. 0, 000­000 Control Design for a Gas capture The semi-closed oxy-fuel gas turbine cycle has been suggested in (Ulizar and Pilidis, 1997 in Section 2), is based on concept (c) above. The exhaust gas from a gas turbine with CO2 as working fluid

Foss, Bjarne A.

195

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

196

Using an Instructional Engineering Method and a Modeling Tool to Design IMS-LD Units of  

E-Print Network [OSTI]

-LD Units of Learning Gilbert Paquette, Ileana de la Teja, Michel Léonard, Karin Lund- gren-Cayrol, Olga designers, in that it represents a more pedagogical viewpoint than software engineering graphical languages

Paris-Sud XI, Université de

197

Developing Model Constraints on Northern Extra-Tropical Carbon Cycling Based on measurements of the Abundance and Isotopic Composition of Atmospheric CO2  

SciTech Connect (OSTI)

The objective of this project was to perform CO2 data syntheses and modeling activities to address two central questions: 1) how much has the seasonal cycle in atmospheric CO2 at northern high latitudes changed since the 1960s, and 2) how well do prognostic biospheric models represent these changes. This project also supported the continuation of the Scripps time series of CO2 isotopes and concentration at ten baseline stations distributed globally.

Keeling, Ralph [UCSD-SIO

2014-12-12T23:59:59.000Z

198

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

SciTech Connect (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

199

Hydraulic Hybrid and Conventional Parcel Delivery Vehicles' Measured Laboratory Fuel Economy on Targeted Drive Cycles  

SciTech Connect (OSTI)

This research project compares laboratory-measured fuel economy of a medium-duty diesel powered hydraulic hybrid vehicle drivetrain to both a conventional diesel drivetrain and a conventional gasoline drivetrain in a typical commercial parcel delivery application. Vehicles in this study included a model year 2012 Freightliner P100H hybrid compared to a 2012 conventional gasoline P100 and a 2012 conventional diesel parcel delivery van of similar specifications. Drive cycle analysis of 484 days of hybrid parcel delivery van commercial operation from multiple vehicles was used to select three standard laboratory drive cycles as well as to create a custom representative cycle. These four cycles encompass and bracket the range of real world in-use data observed in Baltimore United Parcel Service operations. The NY Composite cycle, the City Suburban Heavy Vehicle Cycle cycle, and the California Air Resources Board Heavy Heavy-Duty Diesel Truck (HHDDT) cycle as well as a custom Baltimore parcel delivery cycle were tested at the National Renewable Energy Laboratory's Renewable Fuels and Lubricants Laboratory. Fuel consumption was measured and analyzed for all three vehicles. Vehicle laboratory results are compared on the basis of fuel economy. The hydraulic hybrid parcel delivery van demonstrated 19%-52% better fuel economy than the conventional diesel parcel delivery van and 30%-56% better fuel economy than the conventional gasoline parcel delivery van on cycles other than the highway-oriented HHDDT cycle.

Lammert, M. P.; Burton, J.; Sindler, P.; Duran, A.

2014-10-01T23:59:59.000Z

200

Performance of VAV Parallel Fan Powered Terminal Units: Experimental Results and Models  

E-Print Network [OSTI]

with the guidelines for testing fan powered terminal units as specified in ANSI/ASHRAE Standard 130, (1996). Two blowers, controlled by variable speed drives (VSDs), were used to adjust the static pressures upstream and down- stream of the terminal units... Sensor Pressure 0-2 in. w.g. (0-0.5 kPa) Table 5. Test Variable Levels Independent Variable Number of Levels Values Upstream Static Pressure 3 varied from 0.3 to 2 in. w.g. (75 to 498 Pa) Downstream Static Pressure 3 0.1, 0.25, 0.5 in. w.g (25, 62, 125...

Furr, J.; O'Neal, D.; Davis, M.; Bryant, J.; Cramlet, A.

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

Dynamic modeling and control strategies for a micro-CSP plant with thermal storage powered by the Organic Rankine cycle  

E-Print Network [OSTI]

Organic Rankine cycle (ORC) systems are gaining ground as a means of effectively providing sustainable energy. Coupling small-scale ORCs powered by scroll expander- generators with solar thermal collectors and storage can ...

Ireland, Melissa Kara

2014-01-01T23:59:59.000Z

202

Descriptive and Critical Review of Multiregional Econometric Models of the United States  

E-Print Network [OSTI]

A Regional­ National Econometric Model of I taly . " PapersI m pact of the Regional Econometric Model on the Pol i cyG l ickman , N. J . "An Econometric Model of the P h i ladel

Herman, Amy L.

1984-01-01T23:59:59.000Z

203

USEtox - The UNEP-SETAC toxicity model: recommended characterisation factors for human toxicity and freshwater ecotoxicity in Life Cycle Impact Assessment  

SciTech Connect (OSTI)

Background, Aim and Scope. In 2005 a comprehensive comparison of LCIA toxicity characterisation models was initiated by the UNEP-SETAC Life Cycle Initiative, directly involving the model developers of CalTOX, IMPACT 2002, USES-LCA, BETR, EDIP, WATSON, and EcoSense. In this paper we describe this model-comparison process and its results--in particular the scientific consensus model developed by the model developers. The main objectives of this effort were (i) to identify specific sources of differences between the models' results and structure, (ii) to detect the indispensable model components, and (iii) to build a scientific consensus model from them, representing recommended practice. Methods. A chemical test set of 45 organics covering a wide range of property combinations was selected for this purpose. All models used this set. In three workshops, the model comparison participants identified key fate, exposure and effect issues via comparison of the final characterisation factors and selected intermediate outputs for fate, human exposure and toxic effects for the test set applied to all models. Results. Through this process, we were able to reduce inter-model variation from an initial range of up to 13 orders of magnitude down to no more than 2 orders of magnitude for any substance. This led to the development of USEtox, a scientific consensus model that contains only the most influential model elements. These were, for example, process formulations accounting for intermittent rain, defining a closed or open system environment, or nesting an urban box in a continental box. Discussion. The precision of the new characterisation factors (CFs) is within a factor of 100-1000 for human health and 10-100 for freshwater ecotoxicity of all other models compared to 12 orders of magnitude variation between the CFs of each model respectively. The achieved reduction of inter-model variability by up to 11 orders of magnitude is a significant improvement.Conclusions. USEtox provides a parsimonious and transparent tool for human health and ecosystem CF estimates. Based on a referenced database, it has now been used to calculate CFs for several thousand substances and forms the basis of the recommendations from UNEP-SETAC's Life Cycle Initiative regarding characterization of toxic impacts in Life Cycle Assessment. Recommendations and Perspectives. We provide both recommended and interim (not recommended and to be used with caution) characterisation factors for human health and freshwater ecotoxicity impacts. After a process of consensus building among stakeholders on a broad scale as well as several improvements regarding a wider and easier applicability of the model, USEtox will become available to practitioners for the calculation of further CFs.

Rosenbaum, Ralph K.; Bachmann, Till M.; Swirsky Gold, Lois; Huijbregts, Mark A.J.; Jolliet, Olivier; Juraske, Ronnie; Koehler, Annette; Larsen, Henrik F.; MacLeod, Matthew; Margni, Manuele; McKone, Thomas E.; Payet, Jerome; Schuhmacher, Marta; van de Meent, Dik; Hauschild, Michael Z.

2008-02-03T23:59:59.000Z

204

Cycle cover with short cycles Nicole Immorlica  

E-Print Network [OSTI]

Introduction Given a graph and a subset of marked elements (nodes, edges, or some combination thereof), a cycleCycle cover with short cycles Nicole Immorlica£ Mohammad Mahdian£ Vahab S. Mirrokni£ Abstract Cycle for variants of cycle covering problems which bound the size and/or length of the covering cycles

Immorlica, Nicole

205

Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0  

SciTech Connect (OSTI)

This report documents the analysis of the available hydrologic data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.

Drici, Warda

2004-02-01T23:59:59.000Z

206

Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0  

SciTech Connect (OSTI)

This report documents the analysis of the available transport parameter data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.

Drici, Warda

2003-08-01T23:59:59.000Z

207

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]

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...

Ji, Qundi

2010-07-14T23:59:59.000Z

208

AN AGGREGATED VECTORIAL MODEL OF PETROLEUM FLOW IN THE UNITED STATES  

E-Print Network [OSTI]

Demand Model 81. Oil and Gas Reserves Survey 82. Oil and GasReserves in California 59. American Petroleum Institute System 60. Natural Gas

Krishnan, V. V.

2011-01-01T23:59:59.000Z

209

Eddy Fluxes and Sensitivity of the Water Cycle to Spatial Resolution in Idealized Regional Aquaplanet Model Simulations  

SciTech Connect (OSTI)

A multi-scale moisture budget analysis is used to identify the mechanisms responsible for the sensitivity of the water cycle to spatial resolution using idealized regional aquaplanet simulations. In the higher resolution simulations, moisture transport by eddies fluxes dry the boundary layer enhancing evaporation and precipitation. This effect of eddies, which is underestimated by the physics parameterizations in the low-resolution simulations, is found to be responsible for the sensitivity of the water cycle both directly, and through its upscale effect, on the mean circulation. Correlations among moisture transport by eddies at adjacent ranges of scales provides the potential for reducing this sensitivity by representing the unresolved eddies by their marginally resolved counterparts.

Hagos, Samson M.; Leung, Lai-Yung R.; Gustafson, William I.; Singh, Balwinder

2014-02-28T23:59:59.000Z

210

Integrating Human Indoor Air Pollutant Exposure within Life Cycle Impact Assessment  

E-Print Network [OSTI]

currently done in Life Cycle Assessment (LCA), may result inexposure models; Life Cycle Assessment; LCA; intake fractionneglected in Life Cycle Assessment (LCA). Such an omission

Hellweg, Stefanie

2010-01-01T23:59:59.000Z

211

Groundwater Model Validation for the Project Shoal Area, Corrective Action Unit 447  

SciTech Connect (OSTI)

Stoller has examined newly collected water level data in multiple wells at the Shoal site. On the basis of these data and information presented in the report, we are currently unable to confirm that the model is successfully validated. Most of our concerns regarding the model stem from two findings: (1) measured water level data do not provide clear evidence of a prevailing lateral flow direction; and (2) the groundwater flow system has been and continues to be in a transient state, which contrasts with assumed steady-state conditions in the model. The results of DRI's model validation efforts and observations made regarding water level behavior are discussed in the following sections. A summary of our conclusions and recommendations for a path forward are also provided in this letter report.

None

2008-05-19T23:59:59.000Z

212

AN AGGREGATED VECTORIAL MODEL OF PETROLEUM FLOW IN THE UNITED STATES  

E-Print Network [OSTI]

I I I I I DOMESTIC CRUDE OIL PRODUCTION CRUDE OIL i SUPPLY IDatabase 71. Crude Oil and Natural Gas Production Model 72.Domestic Crude Production SYSTEM: Crude Oil First Purchaser

Krishnan, V. V.

2011-01-01T23:59:59.000Z

213

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]

Methodology iii Life-Cycle Assessment (LCA) . . . . . . .Results 6.1 Life-Cycle Assessment (LCA) . . . . . 6.1.1Analysis (LCEA) 4. Life-Cycle Assessment (LCA) 5. Exergetic

Lettieri, David

2012-01-01T23:59:59.000Z

214

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 Tool Summary LAUNCH TOOL Name: NETL - Petroleum-Based Fuels Life Cycle...

215

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

SciTech Connect (OSTI)

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

216

AN AGGREGATED VECTORIAL MODEL OF PETROLEUM FLOW IN THE UNITED STATES  

E-Print Network [OSTI]

PROCESSING - CONSUMPTION 49. Tanker and Barge Crude Oil andCrude Oil Pricing Model/System VI W 73. Energy ConsumptionCONSUMPTION :rF I PETROLEUM PRODUCT STORAGE PROCESSING / II I I I i I I REFINERY REFINERY CRUDE OIL

Krishnan, V. V.

2011-01-01T23:59:59.000Z

217

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

218

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

SciTech Connect (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

219

Prediction of future fifteen solar cycles  

E-Print Network [OSTI]

In the previous study (Hiremath 2006a), the solar cycle is modeled as a forced and damped harmonic oscillator and from all the 22 cycles (1755-1996), long-term amplitudes, frequencies, phases and decay factor are obtained. Using these physical parameters of the previous 22 solar cycles and by an {\\em autoregressive model}, we predict the amplitude and period of the future fifteen solar cycles. Predicted amplitude of the present solar cycle (23) matches very well with the observations. The period of the present cycle is found to be 11.73 years. With these encouraging results, we also predict the profiles of future 15 solar cycles. Important predictions are : (i) the period and amplitude of the cycle 24 are 9.34 years and 110 ($\\pm 11$), (ii) the period and amplitude of the cycle 25 are 12.49 years and 110 ($\\pm$ 11), (iii) during the cycles 26 (2030-2042 AD), 27 (2042-2054 AD), 34 (2118-2127 AD), 37 (2152-2163 AD) and 38 (2163-2176 AD), the sun might experience a very high sunspot activity, (iv) the sun might also experience a very low (around 60) sunspot activity during cycle 31 (2089-2100 AD) and, (v) length of the solar cycles vary from 8.65 yrs for the cycle 33 to maximum of 13.07 yrs for the cycle 35.

K. M. Hiremath

2007-04-11T23:59:59.000Z

220

Testing the Cultural Boundaries of a Model of Trust: Subordinate-Manager Relationships in China, Norway and the United States  

E-Print Network [OSTI]

Key Variables for China, Norway, and United States Variablein-Supervisor—China, Norway and US Independent VariableCommunication N China B p R Norway B p R United States B p

Whitener, Ellen M.; Maznevski, Martha L.; Hua, Wei; Saebo, Snorre R.; Ekelund, Bjorn Z.

2000-01-01T23:59:59.000Z

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.


221

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

SciTech Connect (OSTI)

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

222

On the Diurnal Cycle of Deep Convection, High-Level Cloud, and Upper Troposphere Water Vapor in the Multiscale Modeling Framework  

SciTech Connect (OSTI)

The Multiscale Modeling Framework (MMF), also called ‘‘superparameterization’’, embeds a cloud-resolving model (CRM) at each grid column of a general circulation model to replace traditional parameterizations of moist convection and large-scale condensation. This study evaluates the diurnal cycle of deep convection, high-level clouds, and upper troposphere water vapor by applying an infrared (IR) brightness temperature (Tb) and a precipitation radar (PR) simulator to the CRM column data. Simulator results are then compared with IR radiances from geostationary satellites and PR reflectivities from the Tropical Rainfall Measuring Mission (TRMM). While the actual surface precipitation rate in the MMF has a reasonable diurnal phase and amplitude when compared with TRMM observations, the IR simulator results indicate an inconsistency in the diurnal anomalies of high-level clouds between the model and the geostationary satellite data. Primarily because of its excessive high-level clouds, the MMF overestimates the simulated precipitation index (PI) and fails to reproduce the observed diurnal cycle phase relationships among PI, high-level clouds, and upper troposphere relative humidity. The PR simulator results show that over the tropical oceans, the occurrence fraction of reflectivity in excess of 20 dBZ is almost 1 order of magnitude larger than the TRMM data especially at altitudes above 6 km. Both results suggest that the MMF oceanic convection is overactive and possible reasons for this bias are discussed. However, the joint distribution of simulated IR Tb and PR reflectivity indicates that the most intense deep convection is found more often over tropical land than ocean, in agreement with previous observational studies.

Zhang, Yunyan; Klein, Stephen A.; Liu, Chuntao; Tian, Baijun; Marchand, Roger T.; Haynes, J. M.; McCoy, Renata; Zhang, Yuying; Ackerman, Thomas P.

2008-08-22T23:59:59.000Z

223

Alternative refrigerants and refrigeration cycles for domestic refrigerators  

SciTech Connect (OSTI)

This project initially focused on using nonazeotropic refrigerant mixtures (NARMs) in a two-evaporator refrigerator-freezer design using two stages of liquid refrigerant subcooling. This concept was proposed and tested in 1975. The work suggested that the concept was 20% more efficient than the conventional one-evaporator refrigerator-freezer (RF) design. After considerable planning and system modeling based on using a NARM in a Lorenz-Meutzner (L-M) RF, the program scope was broadened to include investigation of a ``dual-loop`` concept where energy savings result from exploiting the less stringent operating conditions needed to satisfy cooling, of the fresh food section. A steady-state computer model (CYCLE-Z) capable of simulating conventional, dual loop, and L-M refrigeration cycles was developed. This model was used to rank the performance of 20 ozone-safe NARMs in the L-M refrigeration cycle while key system parameters were systematically varied. The results indicated that the steady-state efficiency of the L-M design was up to 25% greater than that of a conventional cycle. This model was also used to calculate the performance of other pure refrigerants relative to that of dichlorodifluoromethane, R-12, in conventional and dual-loop RF designs. Projected efficiency gains for these cycles were more modest, ranging from 0 to 10%. Individual compressor calorimeter tests of nine combinations of evaporator and condenser temperatures usually used to map RF compressor performance were carried out with R-12 and two candidate L-M NARMs in several compressors. Several models of a commercially produced two-evaporator RF were obtained as test units. Two dual-loop RF designs were built and tested as part of this project.

Sand, J.R.; Rice, C.L.; Vineyard, E.A.

1992-12-01T23:59:59.000Z

224

Advanced Fuel Cycle Economic Sensitivity Analysis  

SciTech Connect (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

225

Modeling the Effects of Irrigation on Land Surface Fluxes and States over the Conterminous United States: Sensitivity to Input Data and Model Parameters  

SciTech Connect (OSTI)

Previous studies on irrigation impacts on land surface fluxes/states were mainly conducted as sensitivity experiments, with limited analysis of uncertainties from the input data and model irrigation schemes used. In this study, we calibrated and evaluated the performance of irrigation water use simulated by the Community Land Model version 4 (CLM4) against observations from agriculture census. We investigated the impacts of irrigation on land surface fluxes and states over the conterminous United States (CONUS) and explored possible directions of improvement. Specifically, we found large uncertainty in the irrigation area data from two widely used sources and CLM4 tended to produce unrealistically large temporal variations of irrigation demand for applications at the water resources region scale over CONUS. At seasonal to interannual time scales, the effects of irrigation on surface energy partitioning appeared to be large and persistent, and more pronounced in dry than wet years. Even with model calibration to yield overall good agreement with the irrigation amounts from the National Agricultural Statistics Service (NASS), differences between the two irrigation area datasets still dominate the differences in the interannual variability of land surface response to irrigation. Our results suggest that irrigation amount simulated by CLM4 can be improved by (1) calibrating model parameter values to account for regional differences in irrigation demand and (2) accurate representation of the spatial distribution and intensity of irrigated areas.

Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Sacks, William J.; Lei, Huimin; Leung, Lai-Yung R.

2013-09-16T23:59:59.000Z

226

Fuel Cycle Research and Development Program  

Office of Environmental Management (EM)

29, 2009 Fuel Cycle Research and Development DM 195665 5 Identify the governing phenomenology Identify the governing phenomenology Develop a first-principle based model of the...

227

Comparison of water boiling models against recent experimental data, with special emphasis on the bubble ebullition cycle  

E-Print Network [OSTI]

Using recently collected data which was measured with state-of-the-art techniques, models for nucleation site density, bubble departure diameter, and nucleation frequency were compared against the acquired data. The ...

Virgen, Matthew Miguel

2011-01-01T23:59:59.000Z

228

Cycle Track Lessons Learned  

E-Print Network [OSTI]

Cycle Track Lessons Learned #12;Presentation Overview · Bicycling trends · Cycle track lessons learned · What is a "Cycle track"? · Essential design elements of cycle tracks Separation Width Crossing driveways & low-volume streets Signalized intersections #12;Trend in kilometers cycled per year

Bertini, Robert L.

229

A modeling software linking approach for the analysis of an integrated reforming combined cycle with hot potassium carbonate CO[subscript 2] capture  

E-Print Network [OSTI]

The focus of this study is the analysis of an integrated reforming combined cycle (IRCC) with natural gas as fuel input. This IRCC consisted of a hydrogen-fired gas turbine (GT) with a single-pressure steam bottoming cycle ...

Nord, Lars Olof

230

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.

231

Greater flexibility, greater growth: A comparative study of labor and capitalist models in Japan, Germany, and the United States.  

E-Print Network [OSTI]

??After the end of the Second World War, three major economic powers emerged. Japan in Asia, Germany in Europe, and the United States in North… (more)

Thompson, Jay Arthur

2007-01-01T23:59:59.000Z

232

Application of a Rule-Based Model to Estimate Mercury Exchange for Three Background Biomes in the Continental United States  

SciTech Connect (OSTI)

Ecosystems that have low mercury (Hg) concentrations (i.e., not enriched or impacted by geologic or anthropogenic processes) cover most of the terrestrial surface area of the earth yet their role as a net source or sink for atmospheric Hg is uncertain. Here we use empirical data to develop a rule-based model implemented within a geographic information system framework to estimate the spatial and temporal patterns of Hg flux for semiarid deserts, grasslands, and deciduous forests representing 45% of the continental United States. This exercise provides an indication of whether these ecosystems are a net source or sink for atmospheric Hg as well as a basis for recommendation of data to collect in future field sampling campaigns. Results indicated that soil alone was a small net source of atmospheric Hg and that emitted Hg could be accounted for based on Hg input by wet deposition. When foliar assimilation and wet deposition are added to the area estimate of soil Hg flux these biomes are a sink for atmospheric Hg.

Hartman, Jelena S. [University of Nevada, Reno; Weisberg, Peter J [University of Nevada, Reno; Pillai, Rekha [University of Nevada, Reno; Ericksen, Joey A. [University of Nevada, Reno; Gustin, Mae S. [University of Nevada, Reno; Kuiken, Todd [Tennessee Technological University; Zhang, Hong [Tennessee Technological University; Lindberg, Steven Eric [ORNL; Rytuba, J. J. [U.S. Geological Survey, Menlo Park, CA

2009-07-01T23:59:59.000Z

233

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  

SciTech Connect (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

234

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 (OSTI)

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

235

A Stochastic Unit-Commitment Model to Estimate the Costs of Changing Power Plant Operation under High Amounts of Intermittent Wind Power  

E-Print Network [OSTI]

) a market for district heating and process heat. Time series for the wind power production rely on timeA Stochastic Unit-Commitment Model to Estimate the Costs of Changing Power Plant Operation under High Amounts of Intermittent Wind Power Integration Meibom, P.1 , Brand, H.2 , Barth, R.2 and Weber, C

236

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...

Son, Kiyoung

2012-07-16T23:59:59.000Z

237

Investment in Corn-Ethanol Plants in the Midwestern United States: An Analysis Using Reduced-Form and Structural Models1  

E-Print Network [OSTI]

1 Investment in Corn-Ethanol Plants in the Midwestern United States: An Analysis Using Reduced-Form and Structural Models1 C.-Y. Cynthia Lin and Karen E. Thome Abstract Ethanol has attracted considerable policy policy and strategic interactions affect decisions about when and where to invest in building new ethanol

Lin, C.-Y. Cynthia

238

Can dive cycle models predict patterns of foraging behaviour? Diving by common eiders in an Arctic polynya  

E-Print Network [OSTI]

account for the capabilities and limitations of their respiratory system when making foraging decisions. Therefore, while static modelling ap- proaches are an important heuristic tool for elucidating mechanisms), obtaining oxygen (or exchang- ing other respiratory gases; Halsey et al. 2003a; Green et al. 2005

239

UNIT NUMBER:  

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

193 UNIT NUMBER: 197 UNIT NAME: CONCRETE RUBBLE PILE (30) REGULATORY STATUS: AOC LOCATION: Outside plant security fence, north of the plant on Big Bayou Creek on private property....

240

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 (OSTI)

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

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

Comparing cropland net primary production estimates from inventory, a satellite-based model, and a process-based model in the Midwest of the United States  

SciTech Connect (OSTI)

Accurately quantifying the spatial and temporal variability of net primary production (NPP) for croplands is essential to understand regional cropland carbon dynamics. We compared three NPP estimates for croplands in the Midwestern United States: inventory-based estimates using crop yield data from the U.S. Department of Agriculture (USDA) National Agricultural Statistics Service (NASS); estimates from the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) NPP product; and estimates from the General Ensemble biogeochemical Modeling System (GEMS) process-based model. The three methods estimated mean NPP in the range of 469–687 g C m?2 yr?1 and total NPP in the range of 318–490 Tg C yr?1 for croplands in the Midwest in 2007 and 2008. The NPP estimates from crop yield data and the GEMS model showed the mean NPP for croplands was over 650 g C m?2 yr?1 while the MODIS NPP product estimated the mean NPP was less than 500 g C m?2 yr?1. MODIS NPP also showed very different spatial variability of the cropland NPP from the other two methods. We found these differences were mainly caused by the difference in the land cover data and the crop specific information used in the methods. Our study demonstrated that the detailed mapping of the temporal and spatial change of crop species is critical for estimating the spatial and temporal variability of cropland NPP. We suggest that high resolution land cover data with species–specific crop information should be used in satellite-based and process-based models to improve carbon estimates for croplands.

Li, Zhengpeng; Liu, Shuguang; Tan, Zhengxi; Bliss, N.; Young, Claudia J.; West, Tristram O.; Ogle, Stephen

2014-05-06T23:59:59.000Z

242

Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks: results from an atmosphere-ocean general circulation model  

E-Print Network [OSTI]

forests indi- cates that the model representation of competition between plants and microbes for new mineral nitrogen resources is reasonable. Our results suggest a weaker dependence of net land carbon flux on soil moisture changes in tropical regions... National Laboratory, Oak Ridge, TN 37831-6335, USA 2Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1543, USA 3Climate and Global Dynamics Division, National Center for Atmospheric Research...

Thornton, P. E.; Doney, S. C.; Lindsay, Keith; Moore, J. K.; Mahowald, N. M.; Randerson, J. T.; Fung, I.; Lamarque, J. F.; Feddema, Johannes J.

2009-01-01T23:59:59.000Z

243

Dynamic Modeling and Control of Nuclear Reactors Coupled to Closed-Loop Brayton Cycle Systems using SIMULINK{sup TM}  

SciTech Connect (OSTI)

The operation of space reactors for both in-space and planetary operations will require unprecedented levels of autonomy and control. Development of these autonomous control systems will require dynamic system models, effective control methodologies, and autonomous control logic. This paper briefly describes the results of reactor, power-conversion, and control models that are implemented in SIMULINK{sup TM} (Simulink, 2004). SIMULINK{sup TM} is a development environment packaged with MatLab{sup TM} (MatLab, 2004) that allows the creation of dynamic state flow models. Simulation modules for liquid metal, gas cooled reactors, and electrically heated systems have been developed, as have modules for dynamic power-conversion components such as, ducting, heat exchangers, turbines, compressors, permanent magnet alternators, and load resistors. Various control modules for the reactor and the power-conversion shaft speed have also been developed and simulated. The modules are compiled into libraries and can be easily connected in different ways to explore the operational space of a number of potential reactor, power-conversion system configurations, and control approaches. The modularity and variability of these SIMULINK{sup TM} models provides a way to simulate a variety of complete power generation systems. To date, both Liquid Metal Reactors (LMR), Gas Cooled Reactors (GCR), and electric heaters that are coupled to gas-dynamics systems and thermoelectric systems have been simulated and are used to understand the behavior of these systems. Current efforts are focused on improving the fidelity of the existing SIMULINK{sup TM} modules, extending them to include isotopic heaters, heat pipes, Stirling engines, and on developing state flow logic to provide intelligent autonomy. The simulation code is called RPC-SIM (Reactor Power and Control-Simulator)

Wright, Steven A.; Sanchez, Travis [Sandia National Laboratories, Org 6872 MS-1146, PO Box 5800 Albuquerque, New Mexico 87185 (United States)

2005-02-06T23:59:59.000Z

244

Quantum thermodynamic cooling cycle  

E-Print Network [OSTI]

The quantum-mechanical and thermodynamic properties of a 3-level molecular cooling cycle are derived. An inadequacy of earlier models is rectified in accounting for the spontaneous emission and absorption associated with the coupling to the coherent driving field via an environmental reservoir. This additional coupling need not be dissipative, and can provide a thermal driving force - the quantum analog of classical absorption chillers. The dependence of the maximum attainable cooling rate on temperature, at ultra-low temperatures, is determined and shown to respect the recently-established fundamental bound based on the second and third laws of thermodynamics.

Palao, J P; Gordon, J M; Palao, Jose P.; Kosloff, Ronnie; Gordon, Jeffrey M.

2001-01-01T23:59:59.000Z

245

Quantum thermodynamic cooling cycle  

E-Print Network [OSTI]

The quantum-mechanical and thermodynamic properties of a 3-level molecular cooling cycle are derived. An inadequacy of earlier models is rectified in accounting for the spontaneous emission and absorption associated with the coupling to the coherent driving field via an environmental reservoir. This additional coupling need not be dissipative, and can provide a thermal driving force - the quantum analog of classical absorption chillers. The dependence of the maximum attainable cooling rate on temperature, at ultra-low temperatures, is determined and shown to respect the recently-established fundamental bound based on the second and third laws of thermodynamics.

Jose P. Palao; Ronnie Kosloff; Jeffrey M. Gordon

2001-06-08T23:59:59.000Z

246

HUMID AIR TURBINE CYCLE TECHNOLOGY DEVELOPMENT PROGRAM  

SciTech Connect (OSTI)

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

247

numerical models & information Systems, Nice: France (2013)" Environmental impact for offshore wind farms: Geolocalized Life Cycle Assessment (LCA) approach  

E-Print Network [OSTI]

Abstract. This paper presents an approach for Environmental Impact Assessment through the use of geolocalized LCA approach, for fixed and floating offshore wind farms. This work was undertaken within the EUsponsored EnerGEO project, aiming at providing a versatile modeling platform for stakeholders allowing calculation, forecasting and monitoring of environmental impacts of different sources of energy. This paper described the geolocalized LCA approach, and its use for the evaluation of environmental impacts of wind energy. The effects of offshore wind farms on global environnemental impacts are evaluated though the LCA approach. It takes into account the type of wind farm, the construction phase, all technical aspects, the operation and maintenance scheme and the decommissioning. It also includes geolocalized information such as wind resources, bathymetry, accessibility … Environmental impact parameters are accessible through a web service helping the decision makers in assessing the environnemental impacts. 1

Catherine Guermont; Lionel Ménard; Isabelle Blanc

2013-01-01T23:59:59.000Z

248

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

SciTech Connect (OSTI)

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

249

Cycling Losses During Screw Air Compressor Operation  

E-Print Network [OSTI]

efficiency confirmed that modulation only controls are accurately portrayed by traditional part load models under most conditions. It also confirmed that load-unload type controls are accurately modeled when cycle times are longer than 5 minutes. However...

Maxwell, J. B.; Wheeler, G.; Bushnell, D.

250

Integrated Assessment of Hadley Centre (HadCM2) Climate Change Projections on Agricultural Productivity and Irrigation Water Supply in the Conterminous United States.I. Climate change scenarios and impacts on irrigation water supply simulated with the HUMUS model.  

SciTech Connect (OSTI)

This paper describes methodology and results of a study by researchers at PNNL contributing to the water sector study of the U.S. National Assessment of Climate Change. The vulnerability of water resources in the conterminous U.S. to climate change in 10-y periods centered on 2030 and 2095--as projected by the HadCM2 general circulation model--was modeled with HUMUS (Hydrologic Unit Model of the U.S.). HUMUS consists of a GIS that provides data on soils, land use and climate to drive the hydrology model Soil Water Assessment Tool (SWAT). The modeling was done at the scale of the 2101 8-digit USGS hydrologic unit areas (HUA). Results are aggregated to the 4-digit and 2-digit (Major Water Resource Region, MWRR) scales for various purposes. Daily records of temperature and precipitation for 1961-1990 provided the baseline climate. Water yields (WY)--sum of surface and subsurface runoff--increases from the baseline period over most of the U.S. in 2030 and 2095. In 2030, WY increases in the western US and decreases in the central and southeast regions. Notably, WY increases by 139 mm from baseline in the Pacific NW. Decreased WY is projected for the Lower Mississippi and Texas Gulf basins, driven by higher temperatures and reduced precipitation. The HadCM2 2095 scenario projects a climate significantly wetter than baseline, resulting in WY increases of 38%. WY increases are projected throughout the eastern U.S. WY also increases in the western U.S. Climate change also affects the seasonality of the hydrologic cycle. Early snowmelt is induced in western basins, leading to dramatically increased WYs in late winter and early spring. The simulations were run at current (365 ppm) and elevated (560 ppm) atmospheric CO2 concentrations to account for the potential impacts of the CO2-fertilization effect. The effects of climate change scenario were considerably greater than those due to elevated CO2 but the latter, overall, decreased losses and augmented increases in water yield.

Rosenberg, Norman J.; Brown, Robert A.; Izaurralde, R Cesar C.; Thomson, Allison M.

2003-06-30T23:59:59.000Z

251

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

SciTech Connect (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

252

UNIT NUMBER  

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

4 UNIT NAME C-611 Underaround Diesel Tank REGULATORY STATUS: AOC LOCATION: Immediately southeast of C-611 APPROXIMATE DIMENSIONS: 1000 gallon FUNCTION: Diesel storage OPERATIONAL...

253

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

SciTech Connect (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

254

Single-cycle nonlinear optics  

SciTech Connect (OSTI)

Nonlinear optics plays a central role in the advancement of optical science and laser-based technologies. We report on the confinement of the nonlinear interaction of light with matter to a single wave cycle and demonstrate its utility for time-resolved and strong-field science. The electric field of 3.3-femtosecond, 0.72-micron laser pulses with a controlled and measured waveform ionizes atoms near the crests of the central wave cycle, with ionization being virtually switched off outside this interval. Isolated sub-100-attosecond pulses of extreme ultraviolet light (photon energy {approx} 80 electron volts), containing {approx} 0.5 nanojoule of energy, emerge from the interaction with a conversion efficiency of {approx} 10{sup -6}. These tools enable the study of the precision control of electron motion with light fields and electron-electron interactions with a resolution approaching the atomic unit of time ({approx} 24 attoseconds).

Max-Planck-Institut fur Quantenoptik; Goulielmakis, E.; Schultze, M.; Hofstetter, M.; Yakovlev, V. S.; Gagnon, J.; Uiberacker, M.; Aquila, A. L.; gullikson, E. M.; attwood, D. T.; Kienberger, R.; Krausz, F.; Kleineberg, U.

2008-11-05T23:59:59.000Z

255

Surface energy partitioning over four dominant vegetation types across the United States in a coupled regional climate model  

E-Print Network [OSTI]

Slopes Model (PRISM) data) and to standard WRF model output. We found that WRF3-CLM3.5 can capture and Forecasting Model 3­Community Land Model 3.5 (WRF3-CLM3.5), by comparing model output to observations (Ameri simulation of downward solar radiation could reduce the energy flux and temperature biases. After adding

Kueppers, Lara M.

256

Photovoltaics Life Cycle Analysis  

E-Print Network [OSTI]

1 Photovoltaics Life Cycle Analysis Vasilis Fthenakis Center of Life Cycle Analysis Earth & Environmental Engineering Department Columbia University and National Photovoltaic (PV) EHS Research Center (air, water, solid) M, Q E PV array Photovoltaic modules Balance of System (BOS) (Inverters

257

OSPREY Model  

SciTech Connect (OSTI)

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

258

mathematics single cycle  

E-Print Network [OSTI]

47 mathematics education single cycle master's study programme #12;48 single cycle master's study program in Mathematics Education #12;49 single cycle master's study program in Mathematics Education MATHEMATICS EDUCATION The program is in tune with the principles of the Bologna Declaration. · Academic title

Â?umer, Slobodan

259

UNIT NUMBER  

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

6 UNIT NAME C-632-8 Sulfuric Acid Storaqe TaD REGULATORY STATUS CERCLA LOCATION Southwest of C-631 coolin location 76 APPROXIMATE DIMENSIONS 5000 Qal - FUNCTION Sulfuric acid...

260

UNIT NUMBER  

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

3 C-750B Diesel UST UNIT NAME REGULATORY STATUS: AOC LOCATION: Southeast corner of C-750 APPROXIMATE DIMENSIONS: 10,000 gallon FUNCTION: Diesel storage OPERATIONAL STATUS: Removed...

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

UNIT NUMBER  

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

5 UNIT NAME C-633 PCB So111 Site REGULATORY STATUS CERCLA LOCATION C-633 Transformer area (Mac location 75) APPROXIMATE DIMENSIONS I Unknown FUNCTION Soill site OPERATIONAL STATUS...

262

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

SciTech Connect (OSTI)

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

263

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]

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...

Mukherji, Payal Tapandev

2011-02-22T23:59:59.000Z

264

The investigation of exhaust powered, automotive air cycle air conditioning  

E-Print Network [OSTI]

domestic automobiles and trucks because of its proven success. This system requires approximately 4 hp (2. 983 kW)[3] for operation snd employs a pressurized fluorinated hydrocarbon (R-12), hereafter fluorocarbon, as a refrigerant. Most of the research... extraction and avoid the use of a fluorocarbon refrigerant. The maJority of work involved with the new units has associated itself in the area of utilizing an absorption cycle or air cycle. The absorption air conditioning unit differs significantly from...

Holley, James Andrew

1978-01-01T23:59:59.000Z

265

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.

266

Reactive mercury in the troposphere: Model formation and results for Florida, the northeastern United States, and the Atlantic Ocean  

E-Print Network [OSTI]

; published 11 December 2007. [1] We describe the development of a model for transport and photochemistry Atlantic Ocean and Gulf of Mexico, and comparison with aircraft- based measurements in Florida. The model photochemically and correlate in regions dominated by direct emissions. Model results also suggest positive

Sillman, Sanford

267

Life Cycle Assessment of Pavements: A Critical Review of Existing Literature and Research  

E-Print Network [OSTI]

tools related to life- cycle assessment (LCA) applied toaccomplished using a life-cycle assessment (LCA) approach.EIO-LCA (Economic Input-Output Life-Cycle Assessment) model

Santero, Nicholas

2010-01-01T23:59:59.000Z

268

Life-Cycle Evaluation of Concrete Building Construction as a Strategy for Sustainable Cities  

E-Print Network [OSTI]

and use of a new life-cycle assessment (LCA) model forknown as life-cycle assessment (LCA). An LCA employs dataliterature related to life-cycle assessment (LCA) applied to

Stadel, Alexander

2013-01-01T23:59:59.000Z

269

Predicting Hurricane Intensity and Structure Changes Associated with Eyewall Replacement Cycles  

E-Print Network [OSTI]

Predicting Hurricane Intensity and Structure Changes Associated with Eyewall Replacement Cycles replacement cycles are commonly observed in tropical cyclones and are well known to cause fluctuations associated with eyewall replacement cycles in Atlantic Ocean hurricanes. The model input comprises

Kossin, James P.

270

Combined Cycle Cogeneration at NALCO Chemical  

E-Print Network [OSTI]

centrifugal chilling capacity expansion were integrated into the model. The gas turbine selection procedure is out lined. Bid evaulation procedure involved a life cycle cost comparison wherein the bid specification responses for each model turbine were... ~ STEAM USE - LB/HR Figure 1 ? NALCO CHEMICAL COMPANY, NAPERVILLE FACILITIES STEAM USE PROFILE Cogeneration Approach Three modes of cogeneration are typically available. These are steam cycle, gas turbine, and reciprocating engine. Preliminary...

Thunem, C. B.; Jacobs, K. W.; Hanzel, W.

271

Chasing megawatts in combined cycle plants  

SciTech Connect (OSTI)

Combined cycle owners do not have to accept that combined cycle performance must degrade over time. Through low cost testing using existing instrumentation, a method is presented to identify causes for lost generation. A 500 MW combined cycle plant, with two STAG 207EA units, had lost 17 MW since initial operation, and found that: Gas side fouling on A four HRSG`s accounted for 8 MW of the total loss LP steam turbine efficiency was below design on one unit, contributing 3 MW Condenser air removal was poor on both units, a loss of an additional 2 MW Compressor and turbine section efficiency losses on 2 of 4 GT`s cost over 4 MW The test also revealed that the other two GT`s, both cooling towers, and one of the two steam turbines, were performing at or near design. Thus far 3 MW has been recovered, with planning underway for recovery of another 3 MW. The remaining 11 MW, though not immediately recoverable, will be the focus of planning for the next major outage. This simple method can be used at any combined cycle using existing instrumentation, with minimal intrusion on daily operations. The use of redundant measurements and uncertainty analysis assures valid and useful results.

Koch, J. [Power Plant Performance Specialist, Lansdowne, PA (United States); DeGeeter, S. [Ocean State Power, Harrisville, RI (United States); Haynes, C.J. [New England Power Co., Somerset, MA (United States)

1996-05-01T23:59:59.000Z

272

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

E-Print Network [OSTI]

) ............. 181 Table 49: Enhanced Surveillance Summary Statistics (Millions $2004) ....................... 183 Table 50: Regular Surveillance Summary Statistics (Millions $2004) .......................... 184 Table 51: Summary Statistics for Daily Data... ......................................................................................... 34 3.2 Economic/Epidemic Model Development .......................................... 34 3.3 General Framework ............................................................................. 51 3.4 Modeling Combined Economic...

Hagerman, Amy Deann

2011-02-22T23:59:59.000Z

273

FUEL CYCLE POTENTIAL WASTE FOR DISPOSITION  

SciTech Connect (OSTI)

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

274

FUEL CYCLE POTENTIAL WASTE FOR DISPOSITION  

SciTech Connect (OSTI)

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

275

United States Department of  

E-Print Network [OSTI]

Hills National Forest uses such a habitat capability model (HABCAP), but its accuracy is largely unknown, Wildlife Biologist with Black Hills National Forest, Custer, SD 2 South Dakota State UniversityUnited States Department of Agriculture Forest Service Rocky Mountain Forest and Range Experiment

276

CASMO-3/SIMULATE-3 benchmark on Ringhals units  

SciTech Connect (OSTI)

Validation of the Studsvik Core Management System (Studsvik-CMS) is presented on Ringhals units 2, 3, and 4, Westinghouse three-loop, 157-assembly pressurized water reactors (PWRs) operated by the Swedish State Power Board (SSPB). The work is a part of the project to develop full in-house in-core fuel management (ICFM) capability based on a modern reactor physics methodology. The major codes of Studsvik-CMS are the cell data code CASMO-3 and the advanced nodal code SIMULATE-3. The SSPB has used CASMO-3 since its first reloads for both PWR and boiling water reactor units. The code SIMULATE-3 was recently installed for PWRs to replace conventional nodal core models and to obtain pin-power reconstruction capability. The Ringhals cores have several advanced features that make them especially interesting for testing the accuracy of modern nodal methods. The Ringhals units operate on an annual cycle with summer refueling. The analyzed cycles include base load, load-follow, and coastdown operation.

Kurcyusz-Ohlofsson, E.; Johansson, M.; Erikksson, M.; Bernro, R.; Hanberg, J.

1990-01-01T23:59:59.000Z

277

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...

Guarneri, Christine E.

2011-08-08T23:59:59.000Z

278

Renewable Energy Cost Modeling: A Toolkit for Establishing Cost-Based Incentives in the United States; March 2010 -- March 2011  

SciTech Connect (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

279

Variable Density Flow Modeling for Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States  

SciTech Connect (OSTI)

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

280

Integrating Human Indoor Air Pollutant Exposure within Life Cycle Impact Assessment  

SciTech Connect (OSTI)

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

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

Advanced thermochemical hydrogen cycles  

SciTech Connect (OSTI)

The overall objective of this program is to contribute to the development of practical thermochemical cycles for the production of hydrogen from water. Specific goals are: investigate and evaluate the technical and economic viability of thermochemical cycles as an advanced technology for producing hydrogen from water; investigate and evaluate the engineering principles involved in interfacing individual thermochemical cycles with the different thermal energy sources (high temperature fission, solar, and fusion); and conduct a continuing research and development effort to evaluate the use of solid sulfates, oxides and other compounds as potentially advanced cycles and as alternates to H/sub 2/SO/sub 4/ based cycles. Basic thermochemistry studies have been completed for two different steps in the decomposition of bismuth sulfate. Two different bismuth sulfate cycles have been defined for different sulfuric acid strengths. The eventual best cycle will depend on energy required to form sulfuric acid at different concentrations. A solids decomposition facility has been constructed and practical studies of solid decompositions are being conducted. The facility includes a rotary kiln system and a dual-particle fluidized bed system. Evaluation of different types of cycles for coupling with different heat sources is continuing.

Hollabaugh, C.M.; Bowman, M.G.

1981-01-01T23:59:59.000Z

282

Power Plant Cycling Costs  

SciTech Connect (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

283

Life Cycle Cost Estimate  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

Life-cycle costs (LCCs) are all the anticipated costs associated with a project or program alternative throughout its life. This includes costs from pre-operations through operations or to the end of the alternative.This chapter discusses life cycle costs and the role they play in planning.

1997-03-28T23:59:59.000Z

284

Assessment for advanced fuel cycle options in CANDU  

SciTech Connect (OSTI)

The possible options for advanced fuel cycles in CANDU reactors including actinide burning options and thorium cycles were explored and are feasible options to increase the efficiency of uranium utilization and help close the fuel cycle. The actinide burning TRUMOX approach uses a mixed oxide fuel of reprocessed transuranic actinides from PWR spent fuel blended with natural uranium in the CANDU-900 reactor. This system reduced actinide content by 35% and decreased natural uranium consumption by 24% over a PWR once through cycle. The thorium cycles evaluated used two CANDU-900 units, a generator and a burner unit along with a driver fuel feedstock. The driver fuels included plutonium reprocessed from PWR, from CANDU and low enriched uranium (LEU). All three cycles were effective options and reduced natural uranium consumption over a PWR once through cycle. The LEU driven system saw the largest reduction with a 94% savings while the plutonium driven cycles achieved 75% savings for PWR and 87% for CANDU. The high neutron economy, online fuelling and flexible compact fuel make the CANDU system an ideal reactor platform for many advanced fuel cycles.

Morreale, A.C.; Luxat, J.C. [McMaster University, 1280 Main St. W. Hamilton, Ontario, L8S 4L7 (Canada); Friedlander, Y. [AMEC-NSS Ltd., 700 University Ave. 4th Floor, Toronto, Ontario, M5G 1X6 (Canada)

2013-07-01T23:59:59.000Z

285

Evaluation of Energy Conservation Measures by Model Simulation  

E-Print Network [OSTI]

handler units of today's commercial buildings. The economizer cycle has proven potential, and has become increasingly more common. Work has also been done demonstrating that hot and cold deck reset schedules, optimized according to outside air... was simulated and the model used to investigate the effects of economizer cycles and optimization of the hot and cold deck reset schedules. Introduction There is a growing necessity to design energy efficiency and conservation measures into new commercial...

Giebler, T.; Liu, M.; Claridge, D. E.

1998-01-01T23:59:59.000Z

286

A new robust cycle-based inventory control policy  

E-Print Network [OSTI]

Oct 17, 2011 ... Abstract: In this paper, we propose a new robust cycle-based control policy for single installation inventory models with non-stationary uncertain ...

Yupeng Chen

2011-10-17T23:59:59.000Z

287

averaged diurnal cycle: Topics by E-print Network  

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

Fibich, Gadi; Solan, Eilon 2012-01-01 84 Ecological Modelling 174 (2004) 6784 Fuzzy pattern recognition of circadian cycles in ecosystems Environmental Sciences and...

288

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.

289

Comparison of Software Models for Energy Savings from Cool Roofs Joshua New, Oak Ridge National Laboratory (United States)  

E-Print Network [OSTI]

Comparison of Software Models for Energy Savings from Cool Roofs Joshua New, Oak Ridge National consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, Attic of the Department of Energy's (DOE) Building Technologies Office (BTO). The simulation engine used in the RSC

Tennessee, University of

290

Model Evaluation Report for Corrective Action Unit 98: Frenchman Flat, Nevada National Security Site, Nye County, Nevada, Revision 1  

SciTech Connect (OSTI)

Model evaluation focused solely on the PIN STRIPE and MILK SHAKE underground nuclear tests’ contaminant boundaries (CBs) because they had the largest extent, uncertainty, and potential consequences. The CAMBRIC radionuclide migration experiment also had a relatively large CB, but because it was constrained by transport data (notably Well UE-5n), there was little uncertainty, and radioactive decay reduced concentrations before much migration could occur. Each evaluation target and the associated data-collection activity were assessed in turn to determine whether the new data support, or demonstrate conservatism of, the CB forecasts. The modeling team—in this case, the same team that developed the Frenchman Flat geologic, source term, and groundwater flow and transport models—analyzed the new data and presented the results to a PER committee. Existing site understanding and its representation in numerical groundwater flow and transport models was evaluated in light of the new data and the ability to proceed to the CR stage of long-term monitoring and institutional control.

Ruskauff, Greg; Marutzky, Sam

2014-09-01T23:59:59.000Z

291

Seasonal cycle of Precipitation over Major River Basins in South and Southeast Asia: A Review of the CMIP5 climate models data for present climate and future climate projections  

E-Print Network [OSTI]

We review the skill of thirty coupled climate models participating in Coupled Model Intercomparison Project 5 in terms of reproducing properties of the seasonal cycle of precipitation over the major river basins of South and Southeast Asia (Indus, Ganges, Brahmaputra and Mekong) for historical period (1961-2000). We also present projected changes by these models by end of century (2061-2100) under extreme scenario RCP8.5. First, we assess their ability to reproduce observed timings of the monsoon onset and the rate of rapid fractional accumulation (RFA slope) - a measure of seasonality within active monsoon period. Secondly, we apply a threshold-independent seasonality index (SI) - a multiplicative measure of precipitation and extent of its concentration relative to the uniform distribution (relative entropy - RE). We apply SI distinctly for monsoonal precipitation regime (MPR), westerly precipitation regime (WPR) and annual precipitation regime. For present climate, neither any single model nor the multi-mod...

Hasson, Shabeh ul; Lucarini, Valerio; Böhner, Jürgen

2015-01-01T23:59:59.000Z

292

United States  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyTheTwo New EnergyofDEVELOPMENTEnergy 1n n d d eAlan8 United

293

A Scientific Trigger Unit for Space-Based Real-Time Gamma Ray Burst Detection, II - Data Processing Model and Benchmarks  

E-Print Network [OSTI]

The Scientific Trigger Unit (UTS) is a satellite equipment designed to detect Gamma Ray Bursts (GRBs) observed by the onboard 6400 pixels camera ECLAIRs. It is foreseen to equip the low-Earth orbit French-Chinese satellite SVOM and acts as the GRB trigger unit for the mission. The UTS analyses in real-time and in great details the onboard camera data in order to select the GRBs, to trigger a spacecraft slew re-centering each GRB for the narrow field-of-view instruments, and to alert the ground telescope network for GRB follow-up observations. A few GRBs per week are expected to be observed by the camera; the UTS targets a close to 100% trigger efficiency, while being selective enough to avoid fake alerts. This is achieved by running the complex scientific algorithms on a radiation tolerant hardware, based on a FPGA data pre-processor and a CPU with a Real-Time Operating System. The UTS is a scientific software, firmware and hardware co-development. A Data Processing Model (DPM) has been developed to fully val...

Provost, Hervé Le; Flouzat, Christophe; Kestener, Pierre; Chaminade, Thomas; Donati, Modeste; Château, Frédéric; Daly, François; Fontignie, Jean

2014-01-01T23:59:59.000Z

294

The Waldmeier Effect in Sunspot Cycles  

E-Print Network [OSTI]

We discuss two aspects of the Waldmeier Effect, namely (1) the rise times of sunspot cycles are anti-correlated to their strengths (WE1) and (2) the rates of rise of the cycles are correlated to their strengths (WE2). From analysis of four different data sets we conclude that both WE1 and WE2 exist in all the data sets. We study these effects theoretically by introducing suitable stochastic fluctuations in our regular solar dynamo model.

Karak, B B; 10.1007/978-3-642-02859-5_40

2010-01-01T23:59:59.000Z

295

Operational Results of a Closed Brayton Cycle Test-Loop  

SciTech Connect (OSTI)

A number of space and terrestrial power system designs plan to use nuclear reactors that are coupled to Closed-loop Brayton Cycle (CBC) systems to generate electrical power. Because very little experience exists regarding the operational behavior of these systems, Sandia National Laboratories (through its Laboratory Directed Research and Development program) is developing a closed-loop test bed that can be used to determine the operational behavior of these systems and to validate models for these systems. Sandia has contracted Barber-Nichols Corporation to design, fabricate, and assemble a Closed-loop Brayton Cycle (CBC) system. This system was developed by modifying commercially available hardware. It uses a 30 kWe Capstone C-30 gas-turbine unit (www.capstoneturbine.com) with a modified housing that permits the attachment of an electrical heater and a water cooled chiller that are connected to the turbo-machinery in a closed loop. The test-loop reuses the Capstone turbine, compressor, and alternator. The Capstone system's nominal operating point is 1150 K turbine inlet temperature at 96,000 rpm. The annular recuperator and portions of the Capstone control system (inverter) and starter system are also reused. The rotational speed of the turbo-machinery is controlled either by adjusting the alternator load by either using the electrical grid or a separate load bank. This report describes the test-loop hardware SBL-30 (Sandia Brayton Loop-30kWe). Also presented are results of early testing and modeling of the unit. The SBL-30 hardware is currently configured with a heater that is limited to 80 kWth with a maximum outlet temperature of {approx}1000 K.

Wright, Steven A.; Lipinski, Ronald J.; Brown, Nicholas [Sandia National Laboratories, Org 6872 MS-1146, PO Box 5800 Albuquerque, New Mexico 87185 (United States); Fuller, Robert; Nichols, Kenneth [Barber Nichols 6325 W 55th Ave., Arvada, Colorado 80002 (United States)

2005-02-06T23:59:59.000Z

296

Operational results of a Closed Brayton Cycle test-loop.  

SciTech Connect (OSTI)

A number of space and terrestrial power system designs plan to use nuclear reactors that are coupled to Closed-loop Brayton Cycle (CBC) systems to generate electrical power. Because very little experience exists regarding the operational behavior of these systems, Sandia National Laboratories (through its Laboratory Directed Research and Development program) is developing a closed-loop test bed that can be used to determine the operational behavior of these systems and to validate models for these systems. Sandia has contracted Barber-Nichols Corporation to design, fabricate, and assemble a Closed-loop Brayton Cycle (CBC) system. This system was developed by modifying commercially available hardware. It uses a 30 kWe Capstone C-30 gas-turbine unit (www.capstoneturbine.com) with a modified housing that permits the attachment of an electrical heater and a water cooled chiller that are connected to the turbo-machinery in a closed loop. The test-loop reuses the Capstone turbine, compressor, and alternator. The Capstone system's nominal operating point is 1150 K turbine inlet temperature at 96,000 rpm. The annular recuperator and portions of the Capstone control system (inverter) and starter system are also reused. The rotational speed of the turbo-machinery is controlled either by adjusting the alternator load by either using the electrical grid or a separate load bank. This report describes the test-loop hardware SBL-30 (Sandia Brayton Loop-30kWe). Also presented are results of early testing and modeling of the unit. The SBL-30 hardware is currently configured with a heater that is limited to 80 kW{sub th} with a maximum outlet temperature of {approx}1000 K.

Fuller, Robert (Barber Nichols, Arvada, Colorado); Wright, Steven Alan; Nichols, Kenneth Graham. (Barber Nichols, Arvada, Colorado); Brown, Nicholas; Lipinski, Ronald J.

2004-11-01T23:59:59.000Z

297

Air Handling Unit Supply Air Temperature Optimization During Economizer Cycles  

E-Print Network [OSTI]

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...

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

2007-01-01T23:59:59.000Z

298

Environmental Life-cycle Assessment of Passenger Transportation: A Detailed Methodology for Energy, Greenhouse Gas and Criteria Pollutant Inventories of Automobiles, Buses, Light Rail, Heavy Rail and Air v.2  

E-Print Network [OSTI]

Life-cycle Assessment (LCA)..comprehensive life-cycle assessment (LCA) models to quantifyat each stage. Life-cycle Assessment (LCA) The vehicles,

Chester, Mikhail; Horvath, Arpad

2008-01-01T23:59:59.000Z

299

Environmental Life-cycle Assessment of Passenger Transportation: A Detailed Methodology for Energy, Greenhouse Gas and Criteria Pollutant Inventories of Automobiles, Buses, Light Rail, Heavy Rail and Air v.2  

E-Print Network [OSTI]

A Life-Cycle Model of an Automobile, Environmental Science &Cycle Assessment of Automobile/Fuel Options, EnvironmentalCycle Energy Analysis for Automobiles, Society of Automotive

Chester, Mikhail; Horvath, Arpad

2008-01-01T23:59:59.000Z

300

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

SciTech Connect (OSTI)

We analyze simulations of present and future climates in the western U.S. performed with four regional climate models (RCMs) nested within two global ocean-atmosphere climate models. Our primary goal is to assess the range of regional climate responses to increased greenhouse gases in available RCM simulations. The four RCMs used different geographical domains, different increased greenhouse gas scenarios for future-climate simulations, and (in some cases) different lateral boundary conditions. For simulations of the present climate, we compare RCM results to observations and to results of the GCM that provided lateral boundary conditions to the RCM. For future-climate (increased greenhouse gas) simulations, we compare RCM results to each other and to results of the driving GCMs. When results are spatially averaged over the western U.S., we find that the results of each RCM closely follow those of the driving GCM in the same region, in both present and future climates. This is true even though the study area is in some cases a small fraction of the RCM domain. Precipitation responses predicted by the RCMs are in many regions not statistically significant compared to interannual variability. Where the predicted precipitation responses are statistically significant, they are positive. The models agree that near-surface temperatures will increase, but do not agree on the spatial pattern of this increase. The four RCMs produce very different estimates of water content of snow in the present climate, and of the change in this water content in response to increased greenhouse gases.

Duffy, Phil; Arritt, R.; Coquard, J.; Gutowski, William; Han, J.; Iorio, J.; Kim, Jongil; Leung, Lai R.; Roads, J.; Zeledon, E.

2006-03-15T23:59:59.000Z

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.


301

Cycle isolation monitoring  

SciTech Connect (OSTI)

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

302

Malone cycle refrigerator development  

SciTech Connect (OSTI)

This paper describes the progress made in demonstrating a Malone Cycle Refrigerator/Freezer. The Malone cycle is similar to the Stirling cycle but uses a supercritical fluid in place of real gas. In the approach, solid-metal diaphragms are used to seal and sweep the working volumes against the high working fluid pressures required in Malone cycle machines. This feature eliminates the friction and leakage that accounted for nearly half the losses in the best piston-defined Malone cycle machines built to date. The authors successfully built a Malone cycle refrigerator that: (1) used CO{sub 2} as the working fluid, (2) operated at pressures up to 19.3 Mpa (2,800 psi), (3) achieved a cold end metal temperatures of {minus}29 C ({minus}20 F), and (4) produced over 400 Watts of cooling at near ambient temperatures. The critical diaphragm components operated flawlessly throughout characterization and performance testing, supporting the conclusion of high reliability based on analysis of fatigue date and actual strain measurements.

Shimko, M.A.; Crowley, C.J.

1999-07-01T23:59:59.000Z

303

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 (OSTI)

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

304

Soil metagenomics and carbon cycling  

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

Soil metagenomics and carbon cycling Soil metagenomics and carbon cycling Establishing a foundational understanding of the microbial and ecosystem factors that control carbon...

305

Advanced Fuel Cycle Cost Basis  

SciTech Connect (OSTI)

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

306

Advanced Fuel Cycle Cost Basis  

SciTech Connect (OSTI)

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

307

Fuel-Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with...  

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

Fuel-Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with the GREET Model Fuel-Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with the GREET Model This presentation by...

308

Development and application of performance and cost models for the externally-fired combined cycle. Task 1, Volume 2. Topical report, June 1995  

SciTech Connect (OSTI)

Increasing restrictions on emission of pollutants from conventional pulverized coal fired steam (PCFS) plant generating electrical power is raising capital and operating cost of these plants and at the same time lowering plant efficiency. This is creating a need for alternative technologies which result in lower emissions of regulated pollutants and which are thermally more efficient. Natural gas-fired combined cycle power generation systems have lower capital cost and higher efficiencies than conventional coal fired steam plants, and at this time they are the leading contender for new power plant construction in the U.S. But the intermediate and long term cost of these fuels is high and there is uncertainty regarding their long-term price and availability. Coal is a relatively low cost fuel which will be abundantly available in the long term. This has motivated the development of advanced technologies for power production from coal which will have advantages of other fuels. The Externally Fired Combined Cycle (EFCC) is one such technology. Air pollution control/hot gas cleanup issues associated with this technology are described.

Agarwal, P.; Frey, H. [North Carolina State Univ., Raleigh, NC (United States); Rubin, E.S. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

1995-07-01T23:59:59.000Z

309

Quantum Thermodynamic Cycles and Quantum Heat Engines (II)  

E-Print Network [OSTI]

We study the quantum mechanical generalization of force or pressure, and then we extend the classical thermodynamic isobaric process to quantum mechanical systems. Based on these efforts, we are able to study the quantum version of thermodynamic cycles that consist of quantum isobaric process, such as quantum Brayton cycle and quantum Diesel cycle. We also consider the implementation of quantum Brayton cycle and quantum Diesel cycle with some model systems, such as single particle in 1D box and single-mode radiation field in a cavity. These studies lay the microscopic (quantum mechanical) foundation for Szilard-Zurek single molecule engine.

H. T. Quan

2009-03-09T23:59:59.000Z

310

A Coupled Quantum Otto Cycle  

E-Print Network [OSTI]

We study the 1-d isotropic Heisenberg model of two spin-1/2 systems as a quantum heat engine. The engine undergoes a four-step Otto cycle where the two adiabatic branches involve changing the external magnetic field at a fixed value of the coupling constant. We find conditions for the engine efficiency to be higher than the uncoupled model; in particular, we find an upper bound which is tighter than the Carnot bound. A new domain of parameter values is pointed out which was not feasible in the interaction-free model. Locally, each spin seems to effect the flow of heat in a direction opposite to the global temperature gradient. This seeming contradiction to the second law can be resolved in terms of local effective temperature of the spins.

George Thomas; Ramandeep S. Johal

2010-11-03T23:59:59.000Z

311

Life-Cycle Assessment of Pyrolysis Bio-Oil Production  

SciTech Connect (OSTI)

As part ofthe Consortium for Research on Renewable Industrial Materials' Phase I life-cycle assessments ofbiofuels, lifecycle inventory burdens from the production of bio-oil were developed and compared with measures for residual fuel oil. Bio-oil feedstock was produced using whole southern pine (Pinus taeda) trees, chipped, and converted into bio-oil by fast pyrolysis. Input parameters and mass and energy balances were derived with Aspen. Mass and energy balances were input to SimaPro to determine the environmental performance of bio-oil compared with residual fuel oil as a heating fuel. Equivalent functional units of 1 MJ were used for demonstrating environmental preference in impact categories, such as fossil fuel use and global warming potential. Results showed near carbon neutrality of the bio-oil. Substituting bio-oil for residual fuel oil, based on the relative carbon emissions of the two fuels, estimated a reduction in CO2 emissions by 0.075 kg CO2 per MJ of fuel combustion or a 70 percent reduction in emission over residual fuel oil. The bio-oil production life-cycle stage consumed 92 percent of the total cradle-to-grave energy requirements, while feedstock collection, preparation, and transportation consumed 4 percent each. This model provides a framework to better understand the major factors affecting greenhouse gas emissions related to bio-oil production and conversion to boiler fuel during fast pyrolysis.

Steele, Philp; Puettmann, Maureen E.; Penmetsa, Venkata Kanthi; Cooper, Jerome E.

2012-02-01T23:59:59.000Z

312

Termination unit  

SciTech Connect (OSTI)

This invention relates to a termination unit comprising an end-section of a cable. The end section of the cable defines a central longitudinal axis and comprising end-parts of N electrical phases, an end-part of a neutral conductor and a surrounding thermally insulation envelope adapted to comprising a cooling fluid. The end-parts of the N electrical phases and the end-part of the neutral conductor each comprising at least one electrical conductor and being arranged in the cable concentrically around a core former with a phase 1 located relatively innermost, and phase N relatively outermost in the cable, phase N being surrounded by the neutral conductor, electrical insulation being arrange between neighboring electrical phases and between phase N and the neutral conductor, and wherein the end-parts of the neutral conductor and the electrical phases each comprise a contacting surface electrically connected to at least one branch current lead to provide an electrical connection: The contacting surfaces each having a longitudinal extension, and being located sequentially along the longitudinal extension of the end-section of the cable. The branch current leads being individually insulated from said thermally insulation envelope by individual electrical insulators.

Traeholt, Chresten [Frederiksberg, DK; Willen, Dag [Klagshamn, SE; Roden, Mark [Newnan, GA; Tolbert, Jerry C [Carrollton, GA; Lindsay, David [Carrollton, GA; Fisher, Paul W [Heiskell, TN; Nielsen, Carsten Thidemann [Jaegerspris, DK

2014-01-07T23:59:59.000Z

313

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

Computers and Other Electronics in U.S. Homes, by Housing Unit Type, 2009" " Million Housing Units, Final" ,,"Housing Unit Type" ,,"Single-Family Units",,"Apartments in Buildings...

314

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

Air Conditioning in U.S. Homes, by Housing Unit Type, 2009" " Million Housing Units, Final" ,,"Housing Unit Type" ,,"Single-Family Units",,"Apartments in Buildings With" ,"Total...

315

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

Water Heating in U.S. Homes, by Housing Unit Type, 2009" " Million Housing Units, Final" ,,"Housing Unit Type" ,,"Single-Family Units",,"Apartments in Buildings With" ,"Total...

316

Helium process cycle  

DOE Patents [OSTI]

A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

Ganni, Venkatarao (Yorktown, VA)

2008-08-12T23:59:59.000Z

317

Helium process cycle  

DOE Patents [OSTI]

A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

Ganni, Venkatarao (Yorktown, VA)

2007-10-09T23:59:59.000Z

318

Superfluid thermodynamic cycle refrigerator  

DOE Patents [OSTI]

A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, Gregory W. (Santa Fe, NM); Kotsubo, Vincent Y. (La Canada, CA)

1992-01-01T23:59:59.000Z

319

Superfluid thermodynamic cycle refrigerator  

DOE Patents [OSTI]

A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He-[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K. 12 figs.

Swift, G.W.; Kotsubo, V.Y.

1992-12-22T23:59:59.000Z

320

1 Copyright 2003 by ASME IMPROVING LIFE CYCLE ASSESSMENT BY INCLUDING SPATIAL, DYNAMIC AND PLACE-  

E-Print Network [OSTI]

Drawing from the substantial body of literature on life cycle assessment / analysis (LCA), the article models is suggested as a means of improving the impact assessment phase of LCA. Keywords: Life Cycle Assessment, Life Cycle Analysis, Life Cycle Impact Assessment, LCA, Environmental Impact Assessment

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

RESEARCH AND ANALYSIS Comparison of Life-Cycle  

E-Print Network [OSTI]

-output life-cycle assessment (EIO-LCA) model; and SimaPro software equipped with the Franklin database. EIO-LCA model estimated for emis- sions of particulate matter less than 10 micrograms (PM10) resulting from wind

Illinois at Chicago, University of

322

Understanding the petrochemical cycle  

SciTech Connect (OSTI)

The presentation will examine the nature of the supply, demand and profitability cycles that appear to be endemic in the petrochemical industry. The focus will be on the underlying factors that cause cyclicality. Data for ethylene and first line derivatives will be used both to provide quantitative illustrations of the magnitude of the cyclical effects and to give an improved perspective on the forces that drive cylicality. We will also examine to what extent cycle timing may be predictable, and present some scenario based projections.

Sedriks, W. [SRI Consulting, Melno Park, CA (United States)

1996-10-01T23:59:59.000Z

323

Analysis of Cycling Costs in Western Wind and Solar Integration Study  

SciTech Connect (OSTI)

The Western Wind and Solar Integration Study (WWSIS) examined the impact of up to 30% penetration of variable renewable generation on the Western Electricity Coordinating Council system. Although start-up costs and higher operating costs because of part-load operation of thermal generators were included in the analysis, further investigation of additional costs associated with thermal unit cycling was deemed worthwhile. These additional cycling costs can be attributed to increases in capital as well as operations and maintenance costs because of wear and tear associated with increased unit cycling. This analysis examines the additional cycling costs of the thermal fleet by leveraging the results of WWSIS Phase 1 study.

Jordan, G.; Venkataraman, S.

2012-06-01T23:59:59.000Z

324

GENERAL CIRCULATION Energy Cycle  

E-Print Network [OSTI]

process. PE is useful for global energy balance. Solar radiant energy does not reach the Earth equally everywhere. On average, the tropics receive and absorb far more solar energy annually than the polar regionsGENERAL CIRCULATION Contents Energy Cycle Mean Characteristics Momentum Budget Overview Energy

Grotjahn, Richard

325

CLASS DESCRIPTIONS CYCLING SERIES  

E-Print Network [OSTI]

will utilize concepts from the 50-minute cycling class while going the distance to optimal health. Whether you're an avid cyclist, triathlete, or desire a longer class for a greater challenge, join us for this 75-minute AN URBANATHLETE Are you registered to compete in an adventure race like the Men's Health Urbanathlon, Warrior Dash

Pittendrigh, Barry

326

Life cycle assessment  

SciTech Connect (OSTI)

Life-Cycle Assessment (LCA) is a technical, data-based and holistic approach to define and subsequently reduce the environmental burdens associated with a product, process, or activity by identifying and quantifying energy and material usage and waste discharges, assessing the impact of those wastes on the environment, and evaluating and implementing opportunities to effect environmental improvements. The assessment includes the entire life-cycle of the product, process or activity encompassing extraction and processing of raw materials, manufacturing, transportation and distribution, use/reuse, recycling and final disposal. LCA is a useful tool for evaluating the environmental consequences of a product, process, or activity, however, current applications of LCA have not been performed in consistent or easily understood ways. This inconsistency has caused increased criticism of LCA. The EPA recognized the need to develop an LCA framework which could be used to provide consistent use across the board. Also, additional research is needed to enhance the understanding about the steps in the performance of an LCA and its appropriate usage. This paper will present the research activities of the EPA leading toward the development of an acceptable method for conducting LCA`s. This research has resulted in the development of two guidance manuals. The first manual is intended to be a practical guide to conducting and interpreting the life-cycle inventory. A nine-step approach to performing a comprehensive inventory is presented along with the general issues to be addressed. The second manual addresses life-cycle design.

Curran, M.A. [Environmental Protection Agency, Cincinnati, OH (United States)

1994-12-31T23:59:59.000Z

327

SCALE-4 Analysis of LaSalle Unit 1 BWR Commercial Reactor Critical Configuration  

SciTech Connect (OSTI)

Five commercial reactor criticals (CRCs) for the LaSalle Unit 1 boiling-water reactor have been analyzed using KENO V.a, the Monte Carlo criticality code of the SCALE 4 code system. The irradiated fuel assembly isotopics for the criticality analyses were provided by the Waste Package Design team at the Yucca Mountain Project in the United States, who performed the depletion calculations using the SAS2H sequence of SCALE 4. The reactor critical measurements involved two beginning-of-cycle and three middle-of-cycle configurations. The CRCs involved relatively low-cycle burnups, and therefore contained a relatively high gadolinium poison content in the reactor assemblies. This report summarizes the data and methods used in analyzing the critical configurations and assesses the sensitivity of the results to some of the modeling approximations used to represent the gadolinium poison distribution within the assemblies. The KENO V.a calculations, performed using the SCALE 44GROUPNDF5 ENDF/B-V cross-section library, yield predicted k{sub eff} values within about 1% {Delta}k/k relative to reactor measurements for the five CRCs using general 8-pin and 9-pin heterogeneous gadolinium poison pin assembly models.

Gauld, I.C.

2000-03-16T23:59:59.000Z

328

A Scientific Trigger Unit for Space-Based Real-Time Gamma Ray Burst Detection, I - Scientific Software Model and Simulations  

E-Print Network [OSTI]

The on-board Scientific Trigger Unit (UTS) is designed to detect Gamma Ray Bursts (GRBs) in real-time, using the data produced by the ECLAIRs camera, foreseen to equip the future French-Chinese satellite mission SVOM (Space-based Variable Objects Monitor). The UTS produces GRB alerts, sent to the ground for GRB follow-up observations, and requests the spacecraft slew to repoint its narrow field instruments onto the GRB afterglow. Because of the diversity of GRBs in duration and variability, two simultaneously running GRB trigger algorithms are implemented in the UTS, the so called Image Trigger performing systematic sky image reconstruction on time scales above 20 s, and the Count-Rate Trigger, selecting a time scale from 10 ms to 20 s showing an excess in count-rate over background estimate, prior to imaging the excess for localization on the sky. This paper describes both trigger algorithms and their implementation in a library, compiled for the Scientific Software Model (SSM) running on standard Linux mach...

Schanne, Stéphane; Kestener, Pierre; Gros, Aleksandra; Cortial, Marin; Götz, Diego; Sizun, Patrick; Château, Frédéric; Cordier, Bertrand

2014-01-01T23:59:59.000Z

329

World nuclear fuel cycle requirements 1990  

SciTech Connect (OSTI)

This analysis report presents the projected requirements for uranium concentrate and uranium enrichment services to fuel the nuclear power plants expected to be operating under three nuclear supply scenarios. Two of these scenarios, the Lower Reference and Upper Reference cases, apply to the United States, Canada, Europe, the Far East, and other countries with free market economies (FME countries). A No New Orders scenario is presented only for the United States. These nuclear supply scenarios are described in Commercial Nuclear Power 1990: Prospects for the United States and the World (DOE/EIA-0438(90)). This report contains an analysis of the sensitivities of the nuclear fuel cycle projections to different levels and types of projected nuclear capacity, different enrichment tails assays, higher and lower capacity factors, changes in nuclear fuel burnup levels, and other exogenous assumptions. The projections for the United States generally extend through the year 2020, and the FME projections, which include the United States, are provided through 2010. The report also presents annual projections of spent nuclear fuel discharges and inventories of spent fuel. Appendix D includes domestic spent fuel projections through the year 2030 for the Lower and Upper Reference cases and through 2040, the last year in which spent fuel is discharged, for the No New Orders case. These disaggregated projections are provided at the request of the Department of Energy's Office of Civilian Radioactive Waste Management.

Not Available

1990-10-26T23:59:59.000Z

330

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 (OSTI)

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

331

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  

SciTech Connect (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

332

Addendum for the Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, NevadaTest Site, Nye County, Nevada, Revision 0 (page changes)  

SciTech Connect (OSTI)

This document, which makes changes to Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, S-N/99205--074, Revision 0 (May 2006) was prepared to address review comments on this final document provided by the Nevada Division of Environmental Protection (NDEP) in a letter dated June 20, 2006. The document includes revised pages that address NDEP review comments and comments from other document users. Change bars are included on these pages to identify where the text was revised. In addition to the revised pages, the following clarifications are made: • Section 6.0 Conceptual Model Uncertainty Analyses. Please note that in this section figures showing the observed versus simulated well head (Figures 6-1, 6-5, 6-7, 6-16, 6-28, 6-30, 6-32, 6-34, 6-37, 6-42, 6-47, 6-52, 6-57, 6-62, 6-71, and 6-86) have a vertical break in scale on the y axis. • Section 7.0 Parameter Sensitivity Analysis. In Section 7.2, the parameter perturbation analysis defines two components of the objective function PHI. These two components include the WELL component that represents the head portion of the objective function as measured in wells and the FLUX component that represents the lateral boundary flux portion of the objective function. In the text and figures in Section 7.2, the phrases “well portion of the objective function” and “head portion of the objective function” are used interchangeably in discussions of the WELL component of the objective function.

John McCord

2007-05-01T23:59:59.000Z

333

Please cite this article in press as: Hallegatte, S. et al., Business cycles, bifurcations and chaos in a neo-classical model with investment dynamics, Journal of Economic Behavior and Organization (2007), doi:10.1016/j.jebo.2007.05.001  

E-Print Network [OSTI]

B.V. All rights reserved. Keywords: Macroeconomic dynamics; Non-equilibrium modeling; BusinessPlease cite this article in press as: Hallegatte, S. et al., Business cycles, bifurcations and chaos in a neo-classical model with investment dynamics, Journal of Economic Behavior and Organization

Ghil, Michael

334

Performance Analyses of 38 kWe Turbo-Machine Unit for Space Reactor Power Systems  

SciTech Connect (OSTI)

This paper developed a design and investigated the performance of 38 kWe turbo-machine unit for space nuclear reactor power systems with Closed Brayton Cycle (CBC) energy conversion. The compressor and turbine of this unit are scaled versions of the NASA's BRU developed in the sixties and seventies. The performance results of turbo-machine unit are calculated for rotational speed up to 45 krpm, variable reactor thermal power and system pressure, and fixed turbine and compressor inlet temperatures of 1144 K and 400 K. The analyses used a detailed turbo-machine model developed at University of New Mexico that accounts for the various energy losses in the compressor and turbine and the effect of compressibility of the He-Xe (40 mole/g) working fluid with increased flow rate. The model also accounts for the changes in the physical and transport properties of the working fluid with temperature and pressure. Results show that a unit efficiency of 24.5% is achievable at rotation speed of 45 krpm and system pressure of 0.75 MPa, assuming shaft and electrical generator efficiencies of 86.7% and 90%. The corresponding net electric power output of the unit is 38.5 kWe, the flow rate of the working fluid is 1.667 kg/s, the pressure ratio and polytropic efficiency for the compressor are 1.60 and 83.1%, and 1.51 and 88.3% for the turbine.

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

2008-01-21T23:59:59.000Z

335

Stirling cycle engine  

DOE Patents [OSTI]

In a Stirling cycle engine having a plurality of working gas charges separated by pistons reciprocating in cylinders, the total gas content is minimized and the mean pressure equalization among the serial cylinders is improved by using two piston rings axially spaced at least as much as the piston stroke and by providing a duct in the cylinder wall opening in the space between the two piston rings and leading to a source of minimum or maximum working gas pressure.

Lundholm, Gunnar (Lund, SE)

1983-01-01T23:59:59.000Z

336

Technology development life cycle processes.  

SciTech Connect (OSTI)

This report and set of appendices are a collection of memoranda originally drafted in 2009 for the purpose of providing motivation and the necessary background material to support the definition and integration of engineering and management processes related to technology development. At the time there was interest and support to move from Capability Maturity Model Integration (CMMI) Level One (ad hoc processes) to Level Three. As presented herein, the material begins with a survey of open literature perspectives on technology development life cycles, including published data on %E2%80%9Cwhat went wrong.%E2%80%9D The main thrust of the material presents a rational expose%CC%81 of a structured technology development life cycle that uses the scientific method as a framework, with further rigor added from adapting relevant portions of the systems engineering process. The material concludes with a discussion on the use of multiple measures to assess technology maturity, including consideration of the viewpoint of potential users.

Beck, David Franklin

2013-05-01T23:59:59.000Z

337

Closed Brayton cycle power conversion systems for nuclear reactors :  

SciTech Connect (OSTI)

This report describes the results of a Sandia National Laboratories internally funded research program to study the coupling of nuclear reactors to gas dynamic Brayton power conversion systems. The research focused on developing integrated dynamic system models, fabricating a 10-30 kWe closed loop Brayton cycle, and validating these models by operating the Brayton test-loop. The work tasks were performed in three major areas. First, the system equations and dynamic models for reactors and Closed Brayton Cycle (CBC) systems were developed and implemented in SIMULINKTM. Within this effort, both steady state and dynamic system models for all the components (turbines, compressors, reactors, ducting, alternators, heat exchangers, and space based radiators) were developed and assembled into complete systems for gas cooled reactors, liquid metal reactors, and electrically heated simulators. Various control modules that use proportional-integral-differential (PID) feedback loops for the reactor and the power-conversion shaft speed were also developed and implemented. The simulation code is called RPCSIM (Reactor Power and Control Simulator). In the second task an open cycle commercially available Capstone C30 micro-turbine power generator was modified to provide a small inexpensive closed Brayton cycle test loop called the Sandia Brayton test-Loop (SBL-30). The Capstone gas-turbine unit housing was modified to permit the attachment of an electrical heater and a water cooled chiller to form a closed loop. The Capstone turbine, compressor, and alternator were used without modification. The Capstone systems nominal operating point is 1150 K turbine inlet temperature at 96,000 rpm. The annular recuperator and portions of the Capstone control system (inverter) and starter system also were reused. The rotational speed of the turbo-machinery is controlled by adjusting the alternator load by using the electrical grid as the load bank. The SBL-30 test loop was operated at the manufacturers site (Barber-Nichols Inc.) and installed and operated at Sandia. A sufficiently detailed description of the loop is provided in this report along with the design characteristics of the turbo-alternator-compressor set to allow other researchers to compare their results with those measured in the Sandia test-loop. The third task consisted of a validation effort. In this task the test loop was operated and compared with the modeled results to develop a more complete understanding of this electrically heated closed power generation system and to validate the model. The measured and predicted system temperatures and pressures are in good agreement, indicating that the model is a reasonable representation of the test loop. Typical deviations between the model and the hardware results are less than 10%. Additional tests were performed to assess the capability of the Brayton engine to continue to remove decay heat after the reactor/heater is shutdown, to develop safe and effective control strategies, and to access the effectiveness of gas inventory control as an alternative means to provide load following. In one test the heater power was turned off to simulate a rapid reactor shutdown, and the turbomachinery was driven solely by the sensible heat stored in the heater for over 71 minutes without external power input. This is an important safety feature for CBC systems as it means that the closed Brayton loop will keep cooling the reactor without the need for auxiliary power (other than that needed to circulate the waste heat rejection coolant) provided the heat sink is available.

Wright, Steven A.; Lipinski, Ronald J.; Vernon, Milton E.; Sanchez, Travis

2006-04-01T23:59:59.000Z

338

Adaptation of the Generalized Carnot Cycle to Describe Thermodynamics of Cerebral Cortex  

E-Print Network [OSTI]

Adaptation of the Generalized Carnot Cycle to Describe Thermodynamics of Cerebral Cortex to the expectant gas-like state. We have modeled the microscopic thermodynamics of the cycle using quantum field theory. Our new result is modeling cortical macroscopic thermodynamics with the generalized Carnot cycle

Freeman, Walter J.

339

Adaptation of the Generalized Carnot Cycle to Describe Thermodynamics of Cerebral Cortex  

E-Print Network [OSTI]

Adaptation of the Generalized Carnot Cycle to Describe Thermodynamics of Cerebral Cortex Freeman to the expectant gas-like state. We have modeled the microscopic thermodynamics of the cycle using quantum field theory. Our new result is modeling cortical macroscopic thermodynamics with the generalized Carnot cycle

Freeman, Walter J.

340

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

2 Computers and Other Electronics in U.S. Homes, by OwnerRenter Status, 2009" " Million Housing Units, Final" ,,,,"Housing Unit Type" ,,,,"Single-Family Units",,,,"Apartments in...

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

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

"Not Asked (Apartments in Buildings" "With 5 or More Units)",19.1,4.4,3.7,6.2,4.7 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

342

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

"Not Asked (Apartments in Buildings" "With 5 or More Units)",19.1,9.6,5,2.2,1.5,0.8 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

343

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

2 Air Conditioning in U.S. Homes, by OwnerRenter Status, 2009" " Million Housing Units, Final" ,,,,"Housing Unit Type" ,,,,"Single-Family Units",,,,"Apartments in Buildings With"...

344

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

2 Water Heating in U.S. Homes, by OwnerRenter Status, 2009" " Million Housing Units, Final" ,,,,"Housing Unit Type" ,,,,"Single-Family Units",,,,"Apartments in Buildings With"...

345

United States Department of  

E-Print Network [OSTI]

Gifford Pinchot Drive Madison, WI #12;2 International system of units (SI conversion factors) Conversion English unit factor SI unit acre 4,046 square meter (m2 ) board foot 0.002 cubic meter (m3 ) bushel (U

346

New Regenerative Cycle for Vapor Compression Refrigeration  

SciTech Connect (OSTI)

This project was a continuation of Category 1 project, completed in August 2005. Following the successful bench model demonstration of the technical feasibility and economic viability, the main objective in this stage was to fabricate the prototype of the heat pump, working on the new thermodynamic cycle. This required further research to increase the system efficiency to the level consistent with theoretical analysis of the cycle. Another group of objectives was to provide the foundation for commercialization and included documentation of the manufacturing process, preparing the business plan, organizing sales network and raising the private capital necessary to acquire production facilities.

Bergander, Mark J [Magnetic Development, Inc.; Butrymowicz, Dariusz [Polish Academy of Scinces

2010-01-26T23:59:59.000Z

347

Synfuels from fusion: producing hydrogen with the Tandem Mirror Reactor and thermochemical cycles  

SciTech Connect (OSTI)

This volume contains the following sections: (1) the Tandem Mirror fusion driver, (2) the Cauldron blanket module, (3) the flowing microsphere, (4) coupling the reactor to the process, (5) the thermochemical cycles, and (6) chemical reactors and process units. (MOW)

Werner, R.W.; Ribe, F.L.

1981-01-21T23:59:59.000Z

348

The Dynamics of Tectonic Tremor Throughout the Seismic Cycle 1. Geophysics Group, Los Alamos National Laboratory  

E-Print Network [OSTI]

Studies, Los Alamos National Laboratory 3. United States Geological Survey, Menlo Park 4. DepartmentThe Dynamics of Tectonic Tremor Throughout the Seismic Cycle 1. Geophysics Group, Los Alamos

Daub,Eric G.

349

Generated using version 3.1.2 of the official AMS LATEX template A Heuristic Model of Dansgaard-Oeschger Cycles: Description,1  

E-Print Network [OSTI]

overturning circulation are10 invoked. Parameterizations are included for latent heat poly~nyas and sea ice a one-layer sea ice model with an9 energy-balance atmosphere; no changes in the large-scale ocean13 or absence of perennial sea ice in the Nordic Seas being the defining characteristic for each14

Battisti, David

350

Reply to Comment on "Analytical Model for the Impulse of Single-Cycle Pulse Detonation Tube" by M. I. Radulescu and  

E-Print Network [OSTI]

their observation, noting that we were aware of the significance of chemical reaction in the products, and our use to model the isentrope in the detonation products in our original study1 in order to simplify extreme cases, at most a 1.3% difference for fuel-air cases, and changes none of the qualitative

Shepherd, Joe

351

HEURISTIC SEARCH FOR HAMILTON CYCLES  

E-Print Network [OSTI]

by combining it with the remaining cycles. The following is the description of the main part of the algorithmHEURISTIC SEARCH FOR HAMILTON CYCLES IN CUBIC GRAPHS Janez ALES, Bojan MOHAR and Tomaz PISANSKI. A successful heuristic algorithm for nding Hamilton cycles in cubic graphs is described. Several graphs from

Mohar, Bojan

352

Edinburgh Research Explorer Money Cycles  

E-Print Network [OSTI]

Edinburgh Research Explorer Money Cycles Citation for published version: Clausen, A & Strub, C 2014 'Money Cycles' Edinburgh School of Economics Discussion Paper Series. Link: Link to publication record date: 11. Dec. 2014 #12;Edinburgh School of Economics Discussion Paper Series Number 249 Money Cycles

Millar, Andrew J.

353

Life cycle assessment of a rock crusher  

SciTech Connect (OSTI)

Nordberg, Inc., a capital equipment manufacturer, performed a Life Cycle Assessment study on its rock crusher to aid in making decisions on product design and energy improvements. Life Cycle Assessment (LCA) is a relatively new cutting edge environmental tool recently standardized by ISO that provides quantitative environmental and energy data on products or processes. This paper commences with a brief introduction to LCA and presents the system boundaries, modeling and assumptions for the rock crusher study. System boundaries include all life major cycle stages except manufacturing and assembly of the crusher. Results of the LCA show that over 99% of most of the flows into and out of the system may be attributed to the use phase of the rock crusher. Within the use phase itself, over 95% of each environmental inflow and outflow (with some exceptions) are attributed to electricity consumption, and not the replacement of spares/wears or lubricating oil over the lifetime of the crusher. Results tables and charts present selected environmental flows, including CO{sub 2} NOx, SOx, particulate matter, and energy consumption, for each of the rock crusher life cycle stages and the use phase. This paper aims to demonstrate the benefits of adopting a rigorous scientific approach to assess energy and environmental impacts over the life cycle of capital equipment. Nordberg has used these results to enhance its engineering efforts toward developing an even more energy efficient machine to further progress its vision of providing economic solutions to its customers by reducing the crusher operating (mainly electricity) costs.

Landfield, A.H.; Karra, V.

1999-07-01T23:59:59.000Z

354

The Organic Rankine Cycle System, Its Application to Extract Energy From Low Temperature Waste Heat  

E-Print Network [OSTI]

in a Rankine Cycle to extract The theoretical Rankine Cycle efficiency (~R) is energy from low temperature waste heat. By 1968, a defined as: 3.8 megawatt unit using R-11 refrigerant was placed in commercial operation in Japan (2) and currently ?ZR.... Figure 2 compares the theo The basic Organic Rankine Cycle may be described retical Rankine efficiency for several hydrocarbons, using the Pressure-Enthalpy Diagram of a typical fluorocarbons and water within the evaporating working fluid (R-11). (See...

Sawyer, R. H.; Ichikawa, S.

1980-01-01T23:59:59.000Z

355

AN AMMONIA-WATER ABSORPTION-HIAT-PUMP CYCLE Donald Kuhlenschmidt, Member ASHRAE  

E-Print Network [OSTI]

,000 Btuh) input unit reported. KLY WORDS Absorption Heat-pump Air conditioning heating Ammonia Donald conditioning chillers. The authors are involved in a project to use this cycle in an air source heat pump the cycle, comment on the design differences compared to the air conditioning application and report

Oak Ridge National Laboratory

356

MULTIPARAMETER OPTIMIZATION STUDIES ON GEOTHERMAL ENERGY CYCLES  

E-Print Network [OSTI]

of Practical Cycles for Geothermal Power Plants." GeneralDesign and Optimize Geothermal Power Cycles." Presented atof Practical Cycles for Geothermal Power Plants." General

Pope, W.L.

2011-01-01T23:59:59.000Z

357

THE TRANSPOSED CRITICAL TEMPERATURE RANKINE THERMODYNAMIC CYCLE  

E-Print Network [OSTI]

Process Program for Geothermal Power Plant Cycles,'*for a Rankine Cycle Geothermal Power Plant," Proceedings,Design and Optimize Geothermal Power Cycles," presented at

Pope, William L.

2012-01-01T23:59:59.000Z

358

Life-cycle Assessment of Semiconductors  

E-Print Network [OSTI]

life-cycle energy requirements (e total ) and global warmingtotal life-cycle global warming impacts. Chapter 3 Life-cycle Energy and Global

Boyd, Sarah B.

2009-01-01T23:59:59.000Z

359

Geothermal Life Cycle Calculator  

SciTech Connect (OSTI)

This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.

Sullivan, John

2014-03-11T23:59:59.000Z

360

Geothermal Life Cycle Calculator  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.

Sullivan, John

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

Beowawe Binary Bottoming Cycle  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment ofEnergyBeowawe Binary Bottoming Cycle

362

A Comparison of Supercritical Carbon Dioxide Power Cycle Configurations with an Emphasis on CSP Applications (Presentation)  

SciTech Connect (OSTI)

Recent research suggests that an emerging power cycle technology using supercritical carbon dioxide (s-CO2) operated in a closed-loop Brayton cycle offers the potential of equivalent or higher cycle efficiency versus supercritical or superheated steam cycles at temperatures relevant for CSP applications. Preliminary design-point modeling suggests that s-CO2 cycle configurations can be devised that have similar overall efficiency but different temperature and/or pressure characteristics. This paper employs a more detailed heat exchanger model than previous work to compare the recompression and partial cooling cycles, two cycles with high design-point efficiencies, and illustrates the potential advantages of the latter. Integration of the cycles into CSP systems is studied, with a focus on sensible heat thermal storage and direct s-CO2 receivers. Results show the partial cooling cycle may offer a larger temperature difference across the primary heat exchanger, thereby potentially reducing heat exchanger cost and improving CSP receiver efficiency.

Neises, T.; Turchi, C.

2013-09-01T23:59:59.000Z

363

Battery Wear from Disparate Duty-Cycles: Opportunities for Electric-Drive Vehicle Battery Health Management; Preprint  

SciTech Connect (OSTI)

Electric-drive vehicles utilizing lithium-ion batteries experience wholly different degradation patterns than do conventional vehicles, depending on geographic ambient conditions and consumer driving and charging patterns. A semi-empirical life-predictive model for the lithium-ion graphite/nickel-cobalt-aluminum chemistry is presented that accounts for physically justified calendar and cycling fade mechanisms. An analysis of battery life for plug-in hybrid electric vehicles considers 782 duty-cycles from travel survey data superimposed with climate data from multiple geographic locations around the United States. Based on predicted wear distributions, opportunities for extending battery life including modification of battery operating limits, thermal and charge control are discussed.

Smith, K.; Earleywine, M.; Wood, E.; Pesaran, A.

2012-10-01T23:59:59.000Z

364

Dynamic Voltage and Frequency Scaling Under a Precise Energy Model Considering  

E-Print Network [OSTI]

is accessed Performance monitoring unit (PMU) ! Won is modeled as: ! PMU on the PXA255 processor chip can ! For DVFS, we use the PMU to generate statistics for " Total no. of instructions being executed (INSTR) " No. of stall cycles due to on/off-chip data dependencies (STALL) " No. of Data Cache misses (DMISS) ! We also

Pedram, Massoud

365

Prediction of Sunspot Cycles by Data Assimilation Method  

E-Print Network [OSTI]

Despite the known general properties of the solar cycles, a reliable forecast of the 11-year sunspot number variations is still a problem. The difficulties are caused by the apparent chaotic behavior of the sunspot numbers from cycle to cycle and by the influence of various turbulent dynamo processes, which are far from understanding. For predicting the solar cycle properties we make an initial attempt to use the Ensemble Kalman Filter (EnKF), a data assimilation method, which takes into account uncertainties of a dynamo model and measurements, and allows to estimate future observational data. We present the results of forecasting of the solar cycles obtained by the EnKF method in application to a low-mode nonlinear dynamical system modeling the solar $\\alpha\\Omega$-dynamo process with variable magnetic helicity. Calculations of the predictions for the previous sunspot cycles show a reasonable agreement with the actual data. This forecast model predicts that the next sunspot cycle will be significantly weaker (by $\\sim 30%$) than the previous cycle, continuing the trend of low solar activity.

I. N. Kitiashvili; A. G. Kosovichev

2009-02-11T23:59:59.000Z

366

Beowawe Bottoming Binary Unit - Final Technical Report for EE0002856  

SciTech Connect (OSTI)

This binary plant is the first high-output refrigeration based waste heat recovery cycle in the industry. Its working fluid is environmentally friendly and as such, the permits that would be required with a butane based cycle are not necessary. The unit is modularized, meaning that the unit’s individual skids were assembled in another location and were shipped via truck to the plant site. This project proves the technical feasibility of using low temperature brine The development of the unit led to the realization of low temperature, high output, and environmentally friendly heat recovery systems through domestic research and engineering. The project generates additional renewable energy for Nevada, resulting in cleaner air and reduced carbon dioxide emissions. Royalty and tax payments to governmental agencies will increase, resulting in reduced financial pressure on local entities. The major components of the unit were sourced from American companies, resulting in increased economic activity throughout the country.

McDonald, Dale Edward

2013-02-12T23:59:59.000Z

367

Life-Cycle Analysis of Transportation Fuels and Vehicle Technologies  

E-Print Network [OSTI]

-cycle modeling for light-duty vehicles GREET CCLUB CCLUB: Carbon Calculator for Land Use Change from Biofuels, and black carbon (in a new release) CO2e of the three (with their global warming potentials) Criteria

Bustamante, Fabián E.

368

Life-cycle assessment of wastewater treatment plants  

E-Print Network [OSTI]

This thesis presents a general model for the carbon footprints analysis of wastewater treatment plants (WWTPs), using a life cycle assessment (LCA) approach. In previous research, the issue of global warming is often related ...

Dong, Bo, M. Eng. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

369

Apparent competition or apparent mutualism? shared predation when populations cycle  

E-Print Network [OSTI]

We use simple mathematical models to explore the indirect interactions between two prey species that share a predator when all three species undergo population cycles. The results are compared to analogous findings for systems that reach a stable...

Abrams, Peter A.; Holt, Robert D.; Roth, James D.

1998-01-01T23:59:59.000Z

370

Predicting the life cycle of rice varieties in Texas  

E-Print Network [OSTI]

once it reaches the market. This study develops a regression model, which includes competition and the characteristics of a specific variety, to estimate the life cycle of new varieties and hybrids. In addition, simulation techniques are utilized...

Gambrell, Stefphanie Michelle

2006-04-12T23:59:59.000Z

371

The Kalina cycle and similar cycles for geothermal power production  

SciTech Connect (OSTI)

This report contains a brief discussion of the mechanics of the Kalina cycle and ideas to extend the concept to other somewhat different cycles. A modified cycle which has a potential heat rejection advantage but little or no performance improvement is discussed. Then, the results of the application of the Kalina cycle and the modified cycle to a geothermal application (360/degree/F resource) are discussed. The results are compared with published results for the Kalina cycle with high temperature sources and estimates about performance at the geothermal temperatures. Finally, the conclusions of this scoping work are given along with recommendations of the direction of future work in this area. 11 refs., 4 figs., 1 tab.

Bliem, C.J.

1988-09-01T23:59:59.000Z

372

Kouchoul cycle implication in the Tailer engine cycle  

SciTech Connect (OSTI)

The author presents here the study of the Tailer engine modified cycle using the concept of load transfer for the Kouchoul cycle. Theoretical equations and numerical simulation of the Tailer engine modified cycle implicating the Kouchoul cycle are developed. The Tailer engine modified cycle can be improved by approaching cycles of spark plug engines by the addition of a phase of cooling of gases to the bottom dead center (bdc). This is possible only by putting a reservoir of cooled gas in communication with the cylinder to the bottom dead center. So as not to complicate the kinematic of the engine, the communication between cylinder and cooled reservoir is executed by some holes of 1 mm distributed on the whole periphery of the cylinder at the bdc.

Arques, P.

1996-12-31T23:59:59.000Z

373

Environmental Life-cycle Assessment of Passenger Transportation: A Detailed Methodology for Energy, Greenhouse Gas and Criteria Pollutant Inventories of Automobiles, Buses, Light Rail, Heavy Rail and Air  

E-Print Network [OSTI]

Life-cycle Assessment (LCA)comprehensive life-cycle assessment (LCA) models to quantifyUCB-ITS-VWP-2007-7 Life-cycle Assessment (LCA) The vehicles,

Chester, Mikhail; Horvath, Arpad

2007-01-01T23:59:59.000Z

374

Phase I Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada with Errata Sheet 1, 2, 3, Revision 1  

SciTech Connect (OSTI)

As prescribed in the Pahute Mesa Corrective Action Investigation Plan (CAIP) (DOE/NV, 1999) and Appendix VI of the Federal Facility Agreement and Consent Order (FFACO) (1996, as amended February 2008), the ultimate goal of transport analysis is to develop stochastic predictions of a contaminant boundary at a specified level of uncertainty. However, because of the significant uncertainty of the model results, the primary goal of this report was modified through mutual agreement between the DOE and the State of Nevada to assess the primary model components that contribute to this uncertainty and to postpone defining the contaminant boundary until additional model refinement is completed. Therefore, the role of this analysis has been to understand the behavior of radionuclide migration in the Pahute Mesa (PM) Corrective Action Unit (CAU) model and to define, both qualitatively and quantitatively, the sensitivity of such behavior to (flow) model conceptualization and (flow and transport) parameterization.

Greg Ruskauff

2009-02-01T23:59:59.000Z

375

Life Cycle Inventory of a CMOS Chip  

E-Print Network [OSTI]

are shown. Keywords- Life Cycle Assessment (LCA); Life Cycleindustry, and Life Cycle Assessment (LCA) is emerging as a

Boyd, Sarah; Dornfeld, David; Krishnan, Nikhil

2006-01-01T23:59:59.000Z

376

Open cycle thermoacoustics  

SciTech Connect (OSTI)

A new type of thermodynamic device combining a thermodynamic cycle with the externally applied steady flow of an open thermodynamic process is discussed and experimentally demonstrated. The gas flowing through this device can be heated or cooled in a series of semi-open cyclic steps. The combination of open and cyclic flows makes possible the elimination of some or all of the heat exchangers (with their associated irreversibility). Heat is directly exchanged with the process fluid as it flows through the device when operating as a refrigerator, producing a staging effect that tends to increase First Law thermodynamic efficiency. An open-flow thermoacoustic refrigerator was built to demonstrate this concept. Several approaches are presented that describe the physical characteristics of this device. Tests have been conducted on this refrigerator with good agreement with a proposed theory.

Reid, Robert Stowers

2000-01-01T23:59:59.000Z

377

Stirling cycle rotary engine  

SciTech Connect (OSTI)

A Stirling cycle rotary engine for producing mechanical energy from heat generated by a heat source external to the engine, the engine including: an engine housing having an interior toroidal cavity with a central housing axis for receiving a working gas, the engine housing further having a cool as inlet port, a compressed gas outlet port, a heated compressed gas inlet port, and a hot exhaust gas outlet port at least three rotors each fixedly mounted to a respective rotor shaft and independently rotatable within the toroidal cavity about the central axis; each of the rotors including a pair of rotor blocks spaced radially on diametrically opposing sides of the respective rotor shaft, each rotor block having a radially fixed curva-linear outer surface for sealed rotational engagement with the engine housing.

Chandler, J.A.

1988-06-28T23:59:59.000Z

378

The sensitivity of modeled ozone to the temporal distribution of point, area, and mobile source emissions in the eastern United States  

E-Print Network [OSTI]

the emissions of NOx from day to night, for example in electric powered vehicles recharged at night, could have vehicles to the fleet (Bloomer et al., 2009) many regulators are focusing on reducing emissions at peak a memorandum of under- standing to reduce NOx emissions from peaking units on high electrical demand days (HEDD

Stehr, Jeffrey

379

Advanced regenerative absorption refrigeration cycles  

DOE Patents [OSTI]

Multi-effect regenerative absorption cycles which provide a high coefficient of performance (COP) at relatively high input temperatures. An absorber-coupled double-effect regenerative cycle (ADR cycle) (10) is provided having a single-effect absorption cycle (SEA cycle) (11) as a topping subcycle and a single-effect regenerative absorption cycle (1R cycle) (12) as a bottoming subcycle. The SEA cycle (11) includes a boiler (13), a condenser (21), an expansion device (28), an evaporator (31), and an absorber (40), all operatively connected together. The 1R cycle (12) includes a multistage boiler (48), a multi-stage resorber (51), a multisection regenerator (49) and also uses the condenser (21), expansion device (28) and evaporator (31) of the SEA topping subcycle (11), all operatively connected together. External heat is applied to the SEA boiler (13) for operation up to about 500 degrees F., with most of the high pressure vapor going to the condenser (21) and evaporator (31) being generated by the regenerator (49). The substantially adiabatic and isothermal functioning of the SER subcycle (12) provides a high COP. For higher input temperatures of up to 700 degrees F., another SEA cycle (111) is used as a topping subcycle, with the absorber (140) of the topping subcycle being heat coupled to the boiler (13) of an ADR cycle (10). The 1R cycle (12) itself is an improvement in that all resorber stages (50b-f) have a portion of their output pumped to boiling conduits (71a-f) through the regenerator (49), which conduits are connected to and at the same pressure as the highest pressure stage (48a) of the 1R multistage boiler (48).

Dao, Kim (14 Nace Ave., Piedmont, CA 94611)

1990-01-01T23:59:59.000Z

380

Fuel-cycle greenhouse gas emissions impacts of alternative transportation fuels and advanced vehicle technologies.  

SciTech Connect (OSTI)

At an international conference on global warming, held in Kyoto, Japan, in December 1997, the United States committed to reduce its greenhouse gas (GHG) emissions by 7% over its 1990 level by the year 2012. To help achieve that goal, transportation GHG emissions need to be reduced. Using Argonne's fuel-cycle model, I estimated GHG emissions reduction potentials of various near- and long-term transportation technologies. The estimated per-mile GHG emissions results show that alternative transportation fuels and advanced vehicle technologies can help significantly reduce transportation GHG emissions. Of the near-term technologies evaluated in this study, electric vehicles; hybrid electric vehicles; compression-ignition, direct-injection vehicles; and E85 flexible fuel vehicles can reduce fuel-cycle GHG emissions by more than 25%, on the fuel-cycle basis. Electric vehicles powered by electricity generated primarily from nuclear and renewable sources can reduce GHG emissions by 80%. Other alternative fuels, such as compressed natural gas and liquefied petroleum gas, offer limited, but positive, GHG emission reduction benefits. Among the long-term technologies evaluated in this study, conventional spark ignition and compression ignition engines powered by alternative fuels and gasoline- and diesel-powered advanced vehicles can reduce GHG emissions by 10% to 30%. Ethanol dedicated vehicles, electric vehicles, hybrid electric vehicles, and fuel-cell vehicles can reduce GHG emissions by over 40%. Spark ignition engines and fuel-cell vehicles powered by cellulosic ethanol and solar hydrogen (for fuel-cell vehicles only) can reduce GHG emissions by over 80%. In conclusion, both near- and long-term alternative fuels and advanced transportation technologies can play a role in reducing the United States GHG emissions.

Wang, M. Q.

1998-12-16T23:59:59.000Z

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.


381

Life-cycle analysis of alternative aviation fuels in GREET  

SciTech Connect (OSTI)

The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, developed at Argonne National Laboratory, has been expanded to include well-to-wake (WTWa) analysis of aviation fuels and aircraft. This report documents the key WTWa stages and assumptions for fuels that represent alternatives to petroleum jet fuel. The aviation module in GREET consists of three spreadsheets that present detailed characterizations of well-to-pump and pump-to-wake parameters and WTWa results. By using the expanded GREET version (GREET1{_}2011), we estimate WTWa results for energy use (total, fossil, and petroleum energy) and greenhouse gas (GHG) emissions (carbon dioxide, methane, and nitrous oxide) for (1) each unit of energy (lower heating value) consumed by the aircraft or (2) each unit of distance traveled/ payload carried by the aircraft. The fuel pathways considered in this analysis include petroleum-based jet fuel from conventional and unconventional sources (i.e., oil sands); Fisher-Tropsch (FT) jet fuel from natural gas, coal, and biomass; bio-jet fuel from fast pyrolysis of cellulosic biomass; and bio-jet fuel from vegetable and algal oils, which falls under the American Society for Testing and Materials category of hydroprocessed esters and fatty acids. For aircraft operation, we considered six passenger aircraft classes and four freight aircraft classes in this analysis. Our analysis revealed that, depending on the feedstock source, the fuel conversion technology, and the allocation or displacement credit methodology applied to co-products, alternative bio-jet fuel pathways have the potential to reduce life-cycle GHG emissions by 55-85 percent compared with conventional (petroleum-based) jet fuel. Although producing FT jet fuel from fossil feedstock sources - such as natural gas and coal - could greatly reduce dependence on crude oil, production from such sources (especially coal) produces greater WTWa GHG emissions compared with petroleum jet fuel production unless carbon management practices, such as carbon capture and storage, are used.

Elgowainy, A.; Han, J.; Wang, M.; Carter, N.; Stratton, R.; Hileman, J.; Malwitz, A.; Balasubramanian, S. (Energy Systems)

2012-07-23T23:59:59.000Z

382

Systems Analyses of Advanced Brayton Cycles  

SciTech Connect (OSTI)

The main objective is to identify and assess advanced improvements to the Brayton Cycle (such as but not limited to firing temperature, pressure ratio, combustion techniques, intercooling, fuel or combustion air augmentation, enhanced blade cooling schemes) that will lead to significant performance improvements in coal based power systems. This assessment is conducted in the context of conceptual design studies (systems studies) that advance state-of-art Brayton cycles and result in coal based efficiencies equivalent to 65% + on natural gas basis (LHV), or approximately an 8% reduction in heat rate of an IGCC plant utilizing the H class steam cooled gas turbine. H class gas turbines are commercially offered by General Electric and Mitsubishi for natural gas based combined cycle applications with 60% efficiency (LHV) and it is expected that such machine will be offered for syngas applications within the next 10 years. The studies are being sufficiently detailed so that third parties will be able to validate portions or all of the studies. The designs and system studies are based on plants for near zero emissions (including CO{sub 2}). Also included in this program is the performance evaluation of other advanced technologies such as advanced compression concepts and the fuel cell based combined cycle. The objective of the fuel cell based combined cycle task is to identify the desired performance characteristics and design basis for a gas turbine that will be integrated with an SOFC in Integrated Gasification Fuel Cell (IGFC) applications. The goal is the conceptualization of near zero emission (including CO{sub 2} capture) integrated gasification power plants producing electricity as the principle product. The capability of such plants to coproduce H{sub 2} is qualitatively addressed. Since a total systems solution is critical to establishing a plant configuration worthy of a comprehensive market interest, a baseline IGCC plant scheme is developed and used to study how alternative process schemes and power cycles might be used and integrated to achieve higher systems efficiency. To achieve these design results, the total systems approach is taken requiring creative integration of the various process units within the plant. Advanced gas turbine based cycles for Integrated gasification Combined cycle (IGCC) applications are identified by a screening analysis and the more promising cycles recommended for detailed systems analysis. In the case of the IGFC task, the main objective is met by developing a steady-state simulation of the entire plant and then using dynamic simulations of the hybrid Solid Oxide Fuel Cell (SOFC)/Gas Turbine sub-system to investigate the turbo-machinery performance. From these investigations the desired performance characteristics and a basis for design of turbo-machinery for use in a fuel cell gas turbine power block is developed.

A.D. Rao; D.J. Francuz; J.D. Maclay; J. Brouwer; A. Verma; M. Li; G.S. Samuelsen

2008-09-30T23:59:59.000Z

383

A mean value soot model (MVSM) was developed and validated for the realtime prediction of the raw, engine-out  

E-Print Network [OSTI]

- ated with an increase in fuel consumption and hence CO2 emissions [10]. Thus it is desirable representative states during the combustion cycle, the developed MVSM determines the engine out soot emissions engine control unit. 16 model parame- ters are used to describe the engine, fuel, and combustion

Daraio, Chiara

384

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

,"Total U.S.1 (millions)" ,," Detached"," Attached"," 2 to 4 Units","5 or More Units","Mobile Homes" "Televisions" "Total Homes",113.6,71.8,6.7,9,19.1,6.9 "Televisions" "Number of...

385

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

in Buildings With" ,,,,"Detached",,"Attached",,"2 to 4 Units",,"5 or More Units",,"Mobile Homes" ,"Total U.S.1 (millions)" "Fuels Used and End Uses",,"Own","Rent","Own","Rent",...

386

Benefits and concerns of a closed nuclear fuel cycle  

SciTech Connect (OSTI)

Nuclear power can play an important role in our energy future, contributing to increasing electricity demand while at the same time decreasing carbon dioxide emissions. However, the nuclear fuel cycle in the United States today is unsustainable. As stated in the 1982 Nuclear Waste Policy Act, the U.S. Department of Energy is responsible for disposing of spent nuclear fuel generated by commercial nuclear power plants operating in a “once-through” fuel cycle in the deep geologic repository located at Yucca Mountain. However, unyielding political opposition to the site has hindered the commissioning process to the extant that the current administration has recently declared the unsuitability of the Yucca Mountain site. In light of this the DOE is exploring other options, including closing the fuel cycle through recycling and reprocessing of spent nuclear fuel. The possibility of closing the fuel cycle is receiving special attention because of its ability to minimize the final high level waste (HLW) package as well as recover additional energy value from the original fuel. The technology is, however, still very controversial because of the increased cost and proliferation risk it can present. To lend perspective on the closed fuel cycle alternative, this presents the arguments for and against closing the fuel cycle with respect to sustainability, proliferation risk, commercial viability, waste management, and energy security.

Widder, Sarah H.

2010-11-17T23:59:59.000Z

387

International nuclear fuel cycle fact book. Revision 4  

SciTech Connect (OSTI)

This Fact Book has been compiled in an effort to provide (1) an overview of worldwide nuclear power and fuel cycle programs and (2) current data concerning fuel cycle and waste management facilities, R and D programs, and key personnel in countries other than the United States. Additional information on each country's program is available in the International Source Book: Nuclear Fuel Cycle Research and Development, PNL-2478, Rev. 2. The Fact Book is organized as follows: (1) Overview section - summary tables which indicate national involvement in nuclear reactor, fuel cycle, and waste management development activities; (2) national summaries - a section for each country which summarizes nuclear policy, describes organizational relationships and provides addresses, names of key personnel, and facilities information; (3) international agencies - a section for each of the international agencies which has significant fuel cycle involvement; (4) energy supply and demand - summary tables, including nuclear power projections; (5) fuel cycle - summary tables; and (6) travel aids - international dialing instructions, international standard time chart, passport and visa requirements, and currency exchange rate.

Harmon, K.M.; Lakey, L.T.; Leigh, I.W.

1984-03-01T23:59:59.000Z

388

International Nuclear Fuel Cycle Fact Book. Revision 5  

SciTech Connect (OSTI)

This Fact Book has been compiled in an effort to provide: (1) an overview of worldwide nuclear power and fuel cycle programs; and (2) current data concerning fuel cycle and waste management facilities, R and D programs, and key personnel in countries other than the United States. Additional information on each country's program is available in the International Source Book: Nuclear Fuel Cycle Research and Development, PNL-2478, Rev. 2. The Fact Book is organized as follows: (1) Overview section - summary tables which indicate national involvement in nuclear reactor, fuel cycle, and waste management development activities; (2) national summaries - a section for each country which summarizes nuclear policy, describes organizational relationships and provides addresses, names of key personnel, and facilities information; (3) international agencies - a section for each of the international agencies which has significant fuel cycle involvement; (4) energy supply and demand - summary tables, including nuclear power projections; (5) fuel cycle - summary tables; and (6) travel aids international dialing instructions, international standard time chart, passport and visa requirements, and currency exchange rate.

Harmon, K.M.; Lakey, L.T.; Leigh, I.W.; Jeffs, A.G.

1985-01-01T23:59:59.000Z

389

Biomass Gasification Combined Cycle  

SciTech Connect (OSTI)

Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

Judith A. Kieffer

2000-07-01T23:59:59.000Z

390

Life Cycle Asset Management  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

(The following directives are deleted or consolidated into this Order and shall be phased out as noted in Paragraph 2: DOE 1332.1A; DOE 4010.1A; DOE 4300.1C; DOE 4320.1B; DOE 4320.2A; DOE 4330.4B; DOE 4330.5; DOE 4540.1C; DOE 4700.1). This Order supersedes specific project management provisions within DOE O 430.1A, LIFE CYCLE ASSET MANAGEMENT. The specific paragraphs canceled by this Order are 6e(7); 7a(3); 7b(11) and (14); 7c(4),(6),(7),(11), and (16); 7d(4) and (8); 7e(3),(10), and (17); Attachment 1, Definitions (item 30 - Line Item Project, item 42 - Project, item 48 - Strategic System); and Attachment 2, Contractor Requirements Document (paragraph 1d regarding a project management system). The remainder of DOE O 430.1A remains in effect. Cancels DOE O 430.1. Canceled by DOE O 413.3.

1998-10-14T23:59:59.000Z

391

Unit Testing Discussion C  

E-Print Network [OSTI]

Unit Testing Discussion C #12;Unit Test public Method is smallest unit of code Input/output transformation Test if the method does what it claims Not exactly black box testing #12;Test if (actual result Expected Computed Input #12;Functionality Computation ­ Easy to test Time based Asynchronous interaction

Massachusetts at Amherst, University of

392

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

in Buildings" "With 5 or More Units)",19.1,4.4,1,0.5,0.5,3.4,2.4,0.6,0.5 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

393

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

"With 5 or More Units)",19.1,2.3,16.8,"N","N","N","N","N","N",2.3,16.8,"N","N" "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

394

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

in Buildings" "With 5 or More Units)",19.1,2,0.7,1.3,2.6,4.1,3.5,2.5,2.4 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

395

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

"With 5 or More Units)",19.1,6.2,3.5,0.5,0.5,1.1,0.6,"Q",0.7,0.4,0.2,2,1.4,0.6 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

396

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

Buildings" "With 5 or More Units)",19.1,4.7,0.9,0.4,0.3,"Q",0.6,0.4,"Q",3.8,2.9,0.9 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

397

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

in Buildings" "With 5 or More Units)",19.1,3.7,2.7,0.9,0.6,0.3,0.9,1,0.2,0.6,0.2 "FoundationBasement of Single-Family" "Units and Apartments in Buildings With" "2 to 4 Units...

398

Orbital Resonance and Solar Cycles  

E-Print Network [OSTI]

We present an analysis of planetary moves, encoded in DE406 ephemerides. We show resonance cycles between most planets in Solar System, of differing quality. The most precise resonance - between Earth and Venus, which not only stabilizes orbits of both planets, locks planet Venus rotation in tidal locking, but also affects the Sun: This resonance group (E+V) also influences Sunspot cycles - the position of syzygy between Earth and Venus, when the barycenter of the resonance group most closely approaches the Sun and stops for some time, relative to Jupiter planet, well matches the Sunspot cycle of 11 years, not only for the last 400 years of measured Sunspot cycles, but also in 1000 years of historical record of "severe winters". We show, how cycles in angular momentum of Earth and Venus planets match with the Sunspot cycle and how the main cycle in angular momentum of the whole Solar system (854-year cycle of Jupiter/Saturn) matches with climatologic data, assumed to show connection with Solar output power and insolation. We show the possible connections between E+V events and Solar global p-Mode frequency changes. We futher show angular momentum tables and charts for individual planets, as encoded in DE405 and DE406 ephemerides. We show, that inner planets orbit on heliocentric trajectories whereas outer planets orbit on barycentric trajectories.

P. A. Semi

2009-03-29T23:59:59.000Z

399

Extreme Financial cycles$ B. Candelonb,  

E-Print Network [OSTI]

Extreme Financial cycles$ B. Candelonb, , G. Gauliera , C. Hurlinb aUniversity Maastricht proposes a new approach to date extreme financial cycles. Elabo- rating on recent methods in extreme value theory, it elaborates an extension of the famous calculus rule to detect extreme peaks and troughs

Paris-Sud XI, Université de

400

Supercritical carbon dioxide cycle control analysis.  

SciTech Connect (OSTI)

This report documents work carried out during FY 2008 on further investigation of control strategies for supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle energy converters. The main focus of the present work has been on investigation of the S-CO{sub 2} cycle control and behavior under conditions not covered by previous work. An important scenario which has not been previously calculated involves cycle operation for a Sodium-Cooled Fast Reactor (SFR) following a reactor scram event and the transition to the primary coolant natural circulation and decay heat removal. The Argonne National Laboratory (ANL) Plant Dynamics Code has been applied to investigate the dynamic behavior of the 96 MWe (250 MWt) Advanced Burner Test Reactor (ABTR) S-CO{sub 2} Brayton cycle following scram. The timescale for the primary sodium flowrate to coast down and the transition to natural circulation to occur was calculated with the SAS4A/SASSYS-1 computer code and found to be about 400 seconds. It is assumed that after this time, decay heat is removed by the normal ABTR shutdown heat removal system incorporating a dedicated shutdown heat removal S-CO{sub 2} pump and cooler. The ANL Plant Dynamics Code configured for the Small Secure Transportable Autonomous Reactor (SSTAR) Lead-Cooled Fast Reactor (LFR) was utilized to model the S-CO{sub 2} Brayton cycle with a decaying liquid metal coolant flow to the Pb-to-CO{sub 2} heat exchangers and temperatures reflecting the decaying core power and heat removal by the cycle. The results obtained in this manner are approximate but indicative of the cycle transient performance. The ANL Plant Dynamics Code calculations show that the S-CO{sub 2} cycle can operate for about 400 seconds following the reactor scram driven by the thermal energy stored in the reactor structures and coolant such that heat removal from the reactor exceeds the decay heat generation. Based on the results, requirements for the shutdown heat removal system may be defined. In particular, the peak heat removal capacity of the shutdown heat removal loop may be specified to be 1.1 % of the nominal reactor power. An investigation of the oscillating cycle behavior calculated by the ANL Plant Dynamics Code under specific conditions has been carried out. It has been found that the calculation of unstable operation of the cycle during power reduction to 0 % may be attributed to the modeling of main compressor operation. The most probable reason for such instabilities is the limit of applicability of the currently used one-dimensional compressor performance subroutines which are based on empirical loss coefficients. A development of more detailed compressor design and performance models is required and is recommended for future work in order to better investigate and possibly eliminate the calculated instabilities. Also, as part of such model development, more reliable surge criteria should be developed for compressor operation close to the critical point. It is expected that more detailed compressor models will be developed as a part of validation of the Plant Dynamics Code through model comparison with the experiment data generated in the small S-CO{sub 2} loops being constructed at Barber-Nichols Inc. and Sandia National Laboratories (SNL). Although such a comparison activity had been planned to be initiated in FY 2008, data from the SNL compression loop currently in operation at Barber Nichols Inc. has not yet become available by the due date of this report. To enable the transient S-CO{sub 2} cycle investigations to be carried out, the ANL Plant Dynamics Code for the S-CO{sub 2} Brayton cycle was further developed and improved. The improvements include further optimization and tuning of the control mechanisms as well as an adaptation of the code for reactor systems other than the Lead-Cooled Fast Reactor (LFR). Since the focus of the ANL work on S-CO{sub 2} cycle development for the majority of the current year has been on the applicability of the cycle to SFRs, work has started on modification of the ANL Plant Dynamics Code to allow

Moisseytsev, A.; Sienicki, J. J. (Nuclear Engineering Division)

2011-04-11T23:59:59.000Z

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.


401

Life Cycle Modeling of Propulsion Materials  

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

propulsion materials manufacturing technologies with an emphasis on aluminum, magnesium, titanium, and ceramics * Advanced propulsion materials' potential in heavy-duty...

402

Emissions Modeling: GREET Life Cycle Analysis  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat PumpRecord ofESPC ENABLE: ECMConstructionApplications | DepartmentEmissions

403

Life Cycle Modeling of Propulsion Materials  

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

and emissions benefits * Downsized engine would also be the most cost-effective option. Cost per mpg fuel economy improvement is estimated to be 15.60 compared to 98 for...

404

The fuel cycle economics of improved uranium utilization in light water reactors  

E-Print Network [OSTI]

A simple fuel cycle cost model has been formulated, tested satisfactorily (within better than 3% for a wide range of cases)

Abbaspour, Ali Tehrani

405

Advanced nuclear fuel cycles - Main challenges and strategic choices  

SciTech Connect (OSTI)

A graphical conceptual model of the uranium fuel cycles has been developed to capture the present, anticipated, and potential (future) nuclear fuel cycle elements. The once-through cycle and plutonium recycle in fast reactors represent two basic approaches that bound classical options for nuclear fuel cycles. Chief among these other options are mono-recycling of plutonium in thermal reactors and recycling of minor actinides in fast reactors. Mono-recycling of plutonium in thermal reactors offers modest savings in natural uranium, provides an alternative approach for present-day interim management of used fuel, and offers a potential bridging technology to development and deployment of future fuel cycles. In addition to breeder reactors' obvious fuel sustainability advantages, recycling of minor actinides in fast reactors offers an attractive concept for long-term management of the wastes, but its ultimate value is uncertain in view of the added complexity in doing so,. Ultimately, there are no simple choices for nuclear fuel cycle options, as the selection of a fuel cycle option must reflect strategic criteria and priorities that vary with national policy and market perspectives. For example, fuel cycle decision-making driven primarily by national strategic interests will likely favor energy security or proliferation resistance issues, whereas decisions driven primarily by commercial or market influences will focus on economic competitiveness.

Le Biez, V. [Corps des Mines, 35 bis rue Saint-Sabin, F-75011 Paris (France); Machiels, A.; Sowder, A. [Electric Power Research Institute, Inc. 3420, Hillview Avenue, Palo Alto, CA 94304 (United States)

2013-07-01T23:59:59.000Z

406

A review of nuclear fuel cycle options for developing nations  

SciTech Connect (OSTI)

A study of several nuclear reactor and fuel cycle options for developing nations was performed. All reactor choices were considered under a GNEP framework. Two advanced alternative reactor types, a nuclear battery-type reactor and a fuel reprocessing fast reactor were examined and compared with a conventional Generation III+ LWR reactor. The burn of nuclear fuel was simulated using ORIGEN 2.2 for each reactor type and the resulting information was used to compare the options in terms of waste produced, waste quality and repository impact. The ORIGEN data was also used to evaluate the economics of the fuel cycles using unit costs, discount rates and present value functions with the material balances. The comparison of the fuel cycles and reactors developed in this work provides a basis for the evaluation of subsidy programs and cost-benefit comparisons for various reactor parameters such as repository impact and proliferation risk versus economic considerations. (authors)

Harrison, R.K.; Scopatz, A.M.; Ernesti, M. [The University of Texas at Austin, Pickle Research Campus, Building 159, Austin, TX 78712 (United States)

2007-07-01T23:59:59.000Z

407

International nuclear fuel cycle fact book: Revision 9  

SciTech Connect (OSTI)

The International Nuclear Fuel Cycle Fact Book has been compiled in an effort to provide current data concerning fuel cycle and waste management facilities, R and D programs and key personnel. The Fact Book contains: national summaries in which a section for each country which summarizes nuclear policy, describes organizational relationships and provides addresses, names of key personnel, and facilities information; and international agencies in which a section for each of the international agencies which has significant fuel cycle involvement, and a listing of nuclear societies. The national summaries, in addition to the data described above, feature a small map for each country as well as some general information. The latter is presented from the perspective of the Fact Book user in the United States.

Leigh, I.W.

1989-01-01T23:59:59.000Z

408

Blade root attachment evaluation low-cycle fatigue estimates based on probabilistic approach  

SciTech Connect (OSTI)

When utilities purchase replacement blades from a manufacturer, the machining tolerances in the root attachment and the material fatigue properties are a major quality concern. These factors can have significant impact on the low-cycle fatigue life. For any replacement blades, the primary concern is to minimize the risk of an in-service failure. However, excessively conservative acceptance criteria would unnecessarily drive up the unit price for the replacement blades. Acceptance criteria with estimates of associated risks of in-service failure are therefore needed for each specific blade design based on the expected operating environment, material, and service life. In the work presented herein, a probabilistic model to estimate LCF in the blade root attachment is presented. The approach is demonstrated using stresses and material fatigue properties for a representative LP last stage blade of a steam turbine. The LCF life estimates obtained using the proposed approach show good correlation with field experience.

Sarlashkar, A.V.; Lam, T.C.T. [Stress Technology Inc., Rochester, NY (United States); McCloskey, T.H. [Electric Power Research Inst., Palo Alto, CA (United States)

1996-12-31T23:59:59.000Z

409

Integrated gasification combined-cycle research development and demonstration activities  

SciTech Connect (OSTI)

The United States Department of Energy (DOE) has selected six integrated gasification combined-cycle (IGCC) advanced power systems for demonstration in the Clean Coal Technology (CCT) Program. DOE`s Office of Fossil Energy, Morgantown Energy Technology Center, is managing a research development and demonstration (RD&D) program that supports the CCT program, and addresses long-term improvements in support of IGCC technology. This overview briefly describes the CCT projects and the supporting RD&D activities.

Ness, H.M.; Reuther, R.B.

1995-12-01T23:59:59.000Z

410

INTRODUCTION TO THE LHC UNIT OVERVIEW  

E-Print Network [OSTI]

by the Standard Model UNIT OBJECTIVES · List the building blocks of matter and the interactions between them · Basic research is a journey--not an event. · The Standard Model is the current framework for our. · Describe fundamental questions not explained by the Standard Model that the LHC and its experiments

Quigg, Chris

411

Coherent regulation in yeast cell cycle network  

E-Print Network [OSTI]

We define a measure of coherent activity for gene regulatory networks, a property that reflects the unity of purpose between the regulatory agents with a common target. We propose that such harmonious regulatory action is desirable under a demand for energy efficiency and may be selected for under evolutionary pressures. We consider two recent models of the cell-cycle regulatory network of the budding yeast, Saccharomyces cerevisiae, as a case study and calculate their degree of coherence. A comparison with random networks of similar size and composition reveals that the yeast's cell-cycle regulation is wired to yield and exceptionally high level of coherent regulatory activity. We also investigate the mean degree of coherence as a function of the network size, connectivity and the fraction of repressory/activatory interactions.

Nese Aral; Alkan Kabakcioglu

2014-12-14T23:59:59.000Z

412

Evaluation and Optimization of a Supercritical Carbon Dioxide Power Conversion Cycle for Nuclear Applications  

SciTech Connect (OSTI)

There have been a number of studies involving the use of gases operating in the supercritical mode for power production and process heat applications. Supercritical carbon dioxide (CO2) is particularly attractive because it is capable of achieving relatively high power conversion cycle efficiencies in the temperature range between 550°C and 750°C. Therefore, it has the potential for use with any type of high-temperature nuclear reactor concept, assuming reactor core outlet temperatures of at least 550°C. The particular power cycle investigated in this paper is a supercritical CO2 Recompression Brayton Cycle. The CO2 Recompression Brayton Cycle can be used as either a direct or indirect power conversion cycle, depending on the reactor type and reactor outlet temperature. The advantage of this cycle when compared to the helium Brayton Cycle is the lower required operating temperature; 550°C versus 850°C. However, the supercritical CO2 Recompression Brayton Cycle requires an operating pressure in the range of 20 MPa, which is considerably higher than the required helium Brayton cycle operating pressure of 8 MPa. This paper presents results of analyses performed using the UniSim process analyses software to evaluate the performance of the supercritical CO2 Brayton Recompression Cycle for different reactor outlet temperatures. The UniSim model assumed a 600 MWt reactor power source, which provides heat to the power cycle at a maximum temperature of between 550°C and 750°C. The UniSim model used realistic component parameters and operating conditions to model the complete power conversion system. CO2 properties were evaluated, and the operating range for the cycle was adjusted to take advantage of the rapidly changing conditions near the critical point. The UniSim model was then optimized to maximize the power cycle thermal efficiency at the different maximum power cycle operating temperatures. The results of the analyses showed that power cycle thermal efficiencies in the range of 40 to 50% can be achieved.

Edwin A. Harvego; Michael G. McKellar

2011-05-01T23:59:59.000Z

413

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]

The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model system is the apprentice of field experts, and `learns' from experts through their past experiences

Shahabi, Cyrus

414

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]

The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model system is the apprentice of field experts, and ,,learns from experts through their past experiences

Wang, Hai

415

Optimization of Air Conditioning Cycling  

E-Print Network [OSTI]

on a 3-ton residential air conditioner are then presented to intuitively understand the effect of expansion valve and evaporator fan cycling in a real system. A real time optimization method is explored and the feasibility, recommendations for a...

Seshadri, Swarooph

2012-10-19T23:59:59.000Z

416

American business cycles and innovation  

E-Print Network [OSTI]

Economists have long studied innovation and its effects on business cycles. Economist Joseph Alois Schumpeter (1883-1950) was the first economist to thoroughly discuss these ideas in his Theorie der wirtschaftlichen Entwicklung, published in 1911...

Hood, Michael

2013-02-22T23:59:59.000Z

417

Life Cycle Inventory of a CMOS Chip  

E-Print Network [OSTI]

Reichl, H. “Life cycle inventory analysis and identificationAllen, D.T. ; “Life cycle inventory development for waferLife Cycle Inventory of a CMOS Chip Sarah Boyd and David

Boyd, Sarah; Dornfeld, David; Krishnan, Nikhil

2006-01-01T23:59:59.000Z

418

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

9 Fuels Used and End Uses in Homes in Midwest Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Midwest Census Region" ,,,"East North Central Census...

419

United States Department of  

E-Print Network [OSTI]

., Ashland, OR 97520 and Gwyneth Myer, Consultant, 220 W. Rapp Rd. Unit 3, Talent, OR 97540. #12;2 THE FIRE

420

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

1 Computers and Other Electronics in Homes in West Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"West Census Region" ,,,"Mountain Census...

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

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

0 Computers and Other Electronics in Homes in South Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"South Census Region" ,,,"South Atlantic Census...

422

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

9 Computers and Other Electronics in Homes in Midwest Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Midwest Census Region" ,,,"East North Central Census...

423

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

8 Computers and Other Electronics in Homes in Northeast Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Northeast Census Region" ,,,"New England Census...

424

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

1 Air Conditioning in Homes in West Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"West Census Region" ,,,"Mountain Census Division",,,"Pacific Census...

425

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

8 Air Conditioning in Homes in Northeast Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Northeast Census Region" ,,,"New England Census Division",,,"Middle...

426

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

0 Air Conditioning in Homes in South Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"South Census Region" ,,,"South Atlantic Census Division",,,,,,"East...

427

" Million Housing Units, Final"  

U.S. Energy Information Administration (EIA) Indexed Site

9 Air Conditioning in Homes in Midwest Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Midwest Census Region" ,,,"East North Central Census...

428

Transmission Business Unit Manager  

Broader source: Energy.gov [DOE]

(See Frequently Asked Questions for more information). Where would I be working? Western Area Power Administration Rocky Mountain Region Transmission Services, (J7300) Transmission Busiess Unit 615...

429

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

9 Water Heating in U.S. Homes in Midwest Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Midwest Census Region" ,,,"East North Central Census...

430

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

0 Water Heating in U.S. Homes in South Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"South Census Region" ,,,"South Atlantic Census Division",,,,,,"East...

431

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

11 Water Heating in U.S. Homes in West Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"West Census Region" ,,,"Mountain Census Division",,,"Pacific...

432

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

8 Water Heating in U.S. Homes in Northeast Region, Divisions, and States, 2009" " Million Housing Units, Final" ,,"Northeast Census Region" ,,,"New England Census...

433

Coupling fuel cycles with repositories: how repository institutional choices may impact fuel cycle design  

SciTech Connect (OSTI)

The historical repository siting strategy in the United States has been a top-down approach driven by federal government decision making but it has been a failure. This policy has led to dispatching fuel cycle facilities in different states. The U.S. government is now considering an alternative repository siting strategy based on voluntary agreements with state governments. If that occurs, state governments become key decision makers. They have different priorities. Those priorities may change the characteristics of the repository and the fuel cycle. State government priorities, when considering hosting a repository, are safety, financial incentives and jobs. It follows that states will demand that a repository be the center of the back end of the fuel cycle as a condition of hosting it. For example, states will push for collocation of transportation services, safeguards training, and navy/private SNF (Spent Nuclear Fuel) inspection at the repository site. Such activities would more than double local employment relative to what was planned for the Yucca Mountain-type repository. States may demand (1) the right to take future title of the SNF so if recycle became economic the reprocessing plant would be built at the repository site and (2) the right of a certain fraction of the repository capacity for foreign SNF. That would open the future option of leasing of fuel to foreign utilities with disposal of the SNF in the repository but with the state-government condition that the front-end fuel-cycle enrichment and fuel fabrication facilities be located in that state.

Forsberg, C. [Massachusetts Institute of Technology, 77 Massachusetts Ave., Room 24-207A Cambridge, MA 02139 (United States); Miller, W.F. [Texas A.M. University System, MS 3133 College Station, TX 77843-3133 (United States)

2013-07-01T23:59:59.000Z

434

Conceptual Model Summary Report Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States  

SciTech Connect (OSTI)

A conceptual model was developed for the Arches Province that integrates geologic and hydrologic information on the Eau Claire and Mt. Simon formations into a geocellular model. The conceptual model describes the geologic setting, stratigraphy, geologic structures, hydrologic features, and distribution of key hydraulic parameters. The conceptual model is focused on the Mt. Simon sandstone and Eau Claire formations. The geocellular model depicts the parameters and conditions in a numerical array that may be imported into the numerical simulations of carbon dioxide (CO{sub 2}) storage. Geophysical well logs, rock samples, drilling logs, geotechnical test results, and reservoir tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. The geologic and hydraulic data were integrated into a three-dimensional (3D) grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data were corrected in locations where reservoir tests have been performed in Mt. Simon injection wells. The final geocellular model covers an area of 600 km by 600 km centered on the Arches Province. The geocellular model includes a total of 24,500,000 cells representing estimated porosity and permeability distribution. CO{sub 2} injection scenarios were developed for on-site and regional injection fields at rates of 70 to 140 million metric tons per year.

None

2011-06-30T23:59:59.000Z

435

Models for evaluation of energy technology and policy options to maximize low carbon source penetration in the United States energy supply.  

SciTech Connect (OSTI)

An initial version of a Systems Dynamics (SD) modeling framework was developed for the analysis of a broad range of energy technology and policy questions. The specific question selected to demonstrate this process was 'what would be the carbon and import implications of expanding nuclear electric capacity to provide power for plug in hybrid vehicles?' Fifteen SNL SD energy models were reviewed and the US Energy and Greenhouse gas model (USEGM) and the Global Nuclear Futures model (GEFM) were identified as the basis for an initial modeling framework. A basic U.S. Transportation model was created to model U.S. fleet changes. The results of the rapid adoption scenario result in almost 40% of light duty vehicles being PHEV by 2040 which requires about 37 GWy/y of additional electricity demand, equivalent to about 25 new 1.4 GWe nuclear plants. The adoption rate of PHEVs would likely be the controlling factor in achieving the associated reduction in carbon emissions and imports.

Pickard, Paul S.; Kataoka, Dawn; Reno, Marissa Devan; Malczynski, Leonard A.; Peplinski, William J.; Roach, Jesse D.; Brainard, James Robert; West, Todd H.; Schoenwald, David Alan

2009-12-01T23:59:59.000Z

436

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 with ROTC 1  

SciTech Connect (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

437

Long-run Implications of a Forest-based Carbon Sequestration Policy on the United States Economy: A Computable General Equilibrium (CGE) Modeling Approach  

E-Print Network [OSTI]

The economic impacts of a government-funded, forest-based sequestration program were analyzed under two different payment schemes. The impacts were obtained by developing a regional, static CGE model built to accommodate a modified IMPLAN SAM for a...

Monge, Juan

2012-10-19T23:59:59.000Z

438

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

E-Print Network [OSTI]

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...

Davis, Michael A.

2011-10-21T23:59:59.000Z

439

Economic Model For a Return on Investment Analysis of United States Government High Performance Computing (HPC) Research and Development (R & D) Investment  

SciTech Connect (OSTI)

This study investigated how high-performance computing (HPC) investments can improve economic success and increase scientific innovation. This research focused on the common good and provided uses for DOE, other government agencies, industry, and academia. The study created two unique economic models and an innovation index: 1 A macroeconomic model that depicts the way HPC investments result in economic advancements in the form of ROI in revenue (GDP), profits (and cost savings), and jobs. 2 A macroeconomic model that depicts the way HPC investments result in basic and applied innovations, looking at variations by sector, industry, country, and organization size. ? A new innovation index that provides a means of measuring and comparing innovation levels. Key findings of the pilot study include: IDC collected the required data across a broad set of organizations, with enough detail to create these models and the innovation index. The research also developed an expansive list of HPC success stories.

Joseph, Earl C.; Conway, Steve; Dekate, Chirag

2013-09-30T23:59:59.000Z

440

Design and history matching of a waterflood/miscible CO? flood model of a mature field: the Wellman Unit, West Texas  

E-Print Network [OSTI]

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...

Rojas Barile, Jose Humberto

2002-01-01T23:59:59.000Z

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.


441

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]

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...

Shao, Hongbin

1994-01-01T23:59:59.000Z

442

M. Bahrami ENSC 461 (S 11) Vapor Power Cycles 1 Vapor Power Cycles  

E-Print Network [OSTI]

is not a suitable model for steam power cycle since: The turbine has to handle steam with low quality which steam is condensed in the condenser 4 3 1 2 s T 1 2 34 s #12;M. Bahrami ENSC 461 (S 11) Vapor Power = 0 qin = h3 ­ h2 Turbine q = 0 wturbine,out = h3 ­ h4 Condenser w = 0 qout = h4 ­ h1 The thermal

Bahrami, Majid

443

United States Environmental  

E-Print Network [OSTI]

Protect Your Family From Lead in Your Home United States Environmental Protection Agency United · What you can do to protect your family · Where to go for more information Before renting or buying Family from Lead Hazards If you think your home has lead-based paint: · Don't try to remove lead

Loudon, Catherine

444

United States Department of  

E-Print Network [OSTI]

Assessment Thomas M. Quigley, Editor U.S. Department of Agriculture Forest Service Pacific Northwest Research, and Andy Wilson. Thomas M. Quigley Editor United States Department of Agriculture Forest Service United Service, Pacific Northwest Research Station. 120 p. (Quigley, Thomas M., ed.; Interior Columbia Basin

Brown, Gregory G.

445

Control system options and strategies for supercritical CO2 cycles.  

SciTech Connect (OSTI)

The Supercritical Carbon Dioxide (S-CO{sub 2}) Brayton Cycle is a promising alternative to Rankine steam cycle and recuperated gas Brayton cycle energy converters for use with Sodium-Cooled Fast Reactors (SFRs), Lead-Cooled Fast Reactors (LFRs), as well as other advanced reactor concepts. The S-CO{sub 2} Brayton Cycle offers higher plant efficiencies than Rankine or recuperated gas Brayton cycles operating at the same liquid metal reactor core outlet temperatures as well as reduced costs or size of key components especially the turbomachinery. A new Plant Dynamics Computer Code has been developed at Argonne National Laboratory for simulation of a S-CO{sub 2} Brayton Cycle energy converter coupled to an autonomous load following liquid metal-cooled fast reactor. The Plant Dynamics code has been applied to investigate the effectiveness of a control strategy for the S-CO{sub 2} Brayton Cycle for the STAR-LM 181 MWe (400 MWt) Lead-Cooled Fast Reactor. The strategy, which involves a combination of control mechanisms, is found to be effective for controlling the S-CO{sub 2} Brayton Cycle over the complete operating range from 0 to 100 % load for a representative set of transient load changes. While the system dynamic analysis of control strategy performance for STARLM is carried out for a S-CO{sub 2} Brayton Cycle energy converter incorporating an axial flow turbine and compressors, investigations of the S-CO{sub 2} Brayton Cycle have identified benefits from the use of centrifugal compressors which offer a wider operating range, greater stability near the critical point, and potentially further cost reductions due to fewer stages than axial flow compressors. Models have been developed at Argonne for the conceptual design and performance analysis of centrifugal compressors for use in the SCO{sub 2} Brayton Cycle. Steady state calculations demonstrate the wider operating range of centrifugal compressors versus axial compressors installed in a S-CO{sub 2} Brayton Cycle as well as the benefits in expanding the range over which individual control mechanisms are effective for cycle control. However, a combination of mechanisms is still required for control of the S-CO{sub 2} Brayton Cycle between 0 and 100 % load. An effort is underway to partially validate the Argonne models and codes by means of comparison with data from tests carried out using the small-scale Sandia Brayton Loop (SBL) recuperated gas closed Brayton cycle facility. The centrifugal compressor model has been compared with data from the SBL operating with nitrogen gas and good agreement is obtained between calculations and the measured data for the compressor outlet pressure versus flow rate, although it is necessary to assume values for certain model parameters which require information about the configuration or dimensions of the compressor components that is unavailable. Unfortunately, the compressor efficiency cannot be compared with experiment data due to the lack of outlet temperature data. A radial inflow turbine model has been developed to enable further comparison of calculations with data from the SBL which incorporates both a radial inflow turbine as well as a radial compressor. Preliminary calculations of pressure ratio and efficiency versus flow rate have been carried out using the radial inflow turbine model.

Moisseytsev, A.; Kulesza, K. P.; Sienicki, J. J.; Nuclear Engineering Division; Oregon State Univ.

2009-06-18T23:59:59.000Z

446

Parametric analyses of single-zone thorium-fueled molten salt reactor fuel cycle options  

SciTech Connect (OSTI)

Analyses of fuel cycle options based on thorium-fueled Molten Salt Reactors (MSRs) have been performed in support of fuel cycle screening and evaluation activities for the United States Department of Energy. The MSR options considered are based on thermal spectrum MSRs with 3 different separations levels: full recycling, limited recycling, and 'once-through' operation without active separations. A single-fluid, single-zone 2250 MWth (1000 MWe) MSR concept consisting of a fuel-bearing molten salt with graphite moderator and reflectors was used as the basis for this study. Radiation transport and isotopic depletion calculations were performed using SCALE 6.1 with ENDF/B-VII nuclear data. New methodology developed at Oak Ridge National Laboratory (ORNL) enables MSR analysis using SCALE, modeling material feed and removal by taking user-specified parameters and performing multiple SCALE/TRITON simulations to determine the resulting equilibrium operating conditions. Parametric analyses examined the sensitivity of the performance of a thorium MSR to variations in the separations efficiency for protactinium and fission products. Results indicate that self-sustained operation is possible with full or limited recycling but once-through operation would require an external neutron source. (authors)

Powers, J.J.; Worrall, A.; Gehin, J.C.; Harrison, T.J.; Sunny, E.E. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6172 (United States)

2013-07-01T23:59:59.000Z

447

Assessment of Possible Cycle Lengths for Fully Encapsulated Microstructure fueled light water reactor Concepts  

SciTech Connect (OSTI)

The use of TRISO-particle-based dispersion fuel within SiC matrix and cladding materials has the potential to allow the design of extremely safe LWRs with failure-proof fuel. This paper examines the feasibility of LWR-like cycle length for such fuel with the imposed constraint of strictly retaining the original geometry of the fuel pins and assemblies. The motivation for retaining the original geometry is to provide the ability to incorporate the fuel “as-is” into existing LWRs while retaining their thermal–hydraulic characteristics. Another mandatory constraint is use of low enriched uranium (at or below 20 w/o). The feasibility of using this fuel is assessed by looking at two factors: cycle lengths and fuel material failure rates. Other considerations (e.g., safety parameters such as reactivity coefficients, feedback, etc.) were not considered at this stage of the study. The study includes the examination of increases in the TRISO kernel sizes without changing the thickness of any of the coating layers. In addition, cases where the buffer layer thickness is allowed to vary are also considered. The study shows that a naïve use of UO2 (even up to 20 w/o enrichment) results in cycle lengths too short to be practical for existing LWR designs and operational demands. Increasing fissile inventory within the fuel compacts shows that acceptable cycle lengths can be achieved. The increase of fissile inventory can be accomplished through multiple means, including higher particle packing fraction, higher enrichment, larger fuel kernel sizes, and the use of higher density fuels (that contain a higher number of U atoms per unit volume). In this study, starting with the recognized highest packing fraction practically achievable (44%), combinations of the other means have been evaluated. The models demonstrate cycle lengths comparable to those of ordinary LWRs. As expected, TRISO particles with extremely large kernels are shown to fail under all considered scenarios. In contrast, the designs that do not depart too drastically from those of the nominal NGNP HTR fuel TRISO particles are shown to perform satisfactorily and display a high rates of survival under all considered scenarios.

R. Sonat Sen; Michael A. Pope; Abderrafi M. Ougouag; Kemal O. Pasamehmetoglu

2013-02-01T23:59:59.000Z

448

Social Scaling: From scale-free to stretched exponential models for scalar stress, hierarchy, levels and units in human and technological networks and evolution1  

E-Print Network [OSTI]

at different levels to reduce information and energy load by substituting relationships among leaders. These characteristics of scale-free modeling have been successful in biology, and social scaling may well follow from individuals to groups as a way of renormalizing information load with respect to human attentional

White, Douglas R.

449

The behavioral manipulation hypothesis Life cycle of  

E-Print Network [OSTI]

1 The behavioral manipulation hypothesis · No one knows how the parasite causes these Life cycle eat mostly hares · Linked cycles? Predator-Prey Cycles? · Think and then discuss: · Under the hypothesis that predators cause this cycle, what would you expect for the following when hare populations

Mitchell, Randall J.

450

Life-cycle Assessment of Semiconductors  

E-Print Network [OSTI]

Environmental Impacts . . . . . . . . . . . . . . . . . . . . . .Abatement Environmental impactLife-cycle Environmental Impacts . . . . . . . LCA of

Boyd, Sarah B.

2009-01-01T23:59:59.000Z

451

Advanced Nuclear Fuel Cycle Options  

SciTech Connect (OSTI)

A systematic evaluation has been conducted of the potential for advanced nuclear fuel cycle strategies and options to address the issues ascribed to the use of nuclear power. Issues included nuclear waste management, proliferation risk, safety, security, economics and affordability, and sustainability. The two basic strategies, once-through and recycle, and the range of possibilities within each strategy, are considered for all aspects of the fuel cycle including options for nuclear material irradiation, separations if needed, and disposal. Options range from incremental changes to today’s implementation to revolutionary concepts that would require the development of advanced nuclear technologies.

Roald Wigeland; Temitope Taiwo; Michael Todosow; William Halsey; Jess Gehin

2010-06-01T23:59:59.000Z

452

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

6 Televisions in U.S. Homes, by Climate Region, 2009" " Million Housing Units, Final" ,,"Climate Region2" ,"Total U.S.1 (millions)" ,,"Very Cold","Mixed- Humid","Mixed-Dry"...

453

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

" Million Housing Units, Final" ,,"Climate Region2" ,"Total U.S.1 (millions)" ,,"Very Cold","Mixed- Humid","Mixed-Dry" "Fuels Used and End Uses",,"Cold",,"Hot-Dry","Hot-Humid...

454

" Million Housing Units, Preliminary"  

U.S. Energy Information Administration (EIA) Indexed Site

Computers and Other Electronics in U.S. Homes, By Number of Household Members, 2009" " Million Housing Units, Preliminary" ,,"Number of Household Members" ,"Total U.S.1 (millions)"...

455

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

3 Computers and Other Electronics in U.S. Homes, by Year of Construction, 2009" " Million Housing Units, Final" ,,"Year of Construction" ,"Total U.S.1 (millions)" ,,"Before...

456

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

7 Computers and Other Electronics in U.S. Homes, by Census Region, 2009" " Million Housing Units, Final" ,,"Census Region" ,"Total U.S.1 (millions)" ,,"Northeast","Midwest","South"...

457

" Million Housing Units, Final"  

U.S. Energy Information Administration (EIA) Indexed Site

5 Computers and Other Electronics in U.S. Homes, by Household Income, 2009" " Million Housing Units, Final" ,,"Household Income" ,"Total U.S.1 (millions)",,,"Below Poverty...

458

Voltage verification unit  

DOE Patents [OSTI]

A voltage verification unit and method for determining the absence of potentially dangerous potentials within a power supply enclosure without Mode 2 work is disclosed. With this device and method, a qualified worker, following a relatively simple protocol that involves a function test (hot, cold, hot) of the voltage verification unit before Lock Out/Tag Out and, and once the Lock Out/Tag Out is completed, testing or "trying" by simply reading a display on the voltage verification unit can be accomplished without exposure of the operator to the interior of the voltage supply enclosure. According to a preferred embodiment, the voltage verification unit includes test leads to allow diagnostics with other meters, without the necessity of accessing potentially dangerous bus bars or the like.

Martin, Edward J. (Virginia Beach, VA)

2008-01-15T23:59:59.000Z

459

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

4 Air Conditioning in U.S. Homes, by Number of Household Members, 2009" " Million Housing Units, Final" ,,"Number of Household Members" ,"Total U.S.1 (millions)" ,,,,,,"5 or More...

460

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

7 Air Conditioning in U.S. Homes, by Census Region, 2009" " Million Housing Units, Final" ,,"Census Region" ,"Total U.S.1 (millions)" ,,"Northeast","Midwest","South","West" "Air...

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.


461

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

3 Air Conditioning in U.S. Homes, by Year of Construction, 2009" " Million Housing Units, Final" ,,"Year of Construction" ,"Total U.S.1 (millions)" ,,"Before 1940","1940 to...

462

" Million Housing Units, Final"  

U.S. Energy Information Administration (EIA) Indexed Site

5 Air Conditioning in U.S. Homes, by Household Income, 2009" " Million Housing Units, Final" ,,"Household Income" ,"Total U.S.1 (millions)",,,"Below Poverty Line2" ,,"Less...

463

United States Environmental Protection  

E-Print Network [OSTI]

environmental problems today and building a science knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce environmental risksUnited States Environmental Protection Agency Hydrogeologic Framework, Ground-Water Geochemistry

464

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

3 Appliances in U.S. Homes, by Year of Construction, 2009" " Million Housing Units, Final" ,,"Year of Construction" ,"Total U.S.1 (millions)" ,,"Before 1940","1940 to 1949","1950...

465

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

3 Televisions in U.S. Homes, by Year of Construction, 2009" " Million Housing Units, Final" ,,"Year of Construction" ,"Total U.S.1 (millions)" ,,"Before 1940","1940 to 1949","1950...

466

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

3 Household Demographics of U.S. Homes, by Year of Construction, 2009" " Million Housing Units, Final" ,,"Year of Construction" ,"Total U.S.1 (millions)" ,,"Before 1940","1940 to...

467

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

5 Water Heating in U.S. Homes, by Household Income, 2009" " Million Housing Units, Final" ,,"Household Income" ,"Total U.S.1 (millions)",,,"Below Poverty Line2" ,,"Less than...

468

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

3 Water Heating in U.S. Homes, by Year of Construction, 2009" " Million Housing Units, Final" ,,"Year of Construction" ,"Total U.S.1 (millions)" ,,"Before 1940","1940 to...

469

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

6 Water Heating in U.S. Homes, by Climate Region, 2009" " Million Housing Units, Final" ,,"Climate Region2" ,"Total U.S.1 (millions)" ,,"Very Cold","Mixed- Humid","Mixed-Dry"...

470

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

7 Water Heating in U.S. Homes, by Census Region, 2009" " Million Housing Units, Final" ,,"Census Region" ,"Total U.S.1 (millions)" ,,"Northeast","Midwest","South","West" "Water...

471

" Million Housing Units, Final...  

U.S. Energy Information Administration (EIA) Indexed Site

4 Water Heating in U.S. Homes, by Number of Household Members, 2009" " Million Housing Units, Final" ,,"Number of Household Members" ,"Total U.S.1 (millions)" ,,,,,,"5 or More...

472