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Note: This page contains sample records for the topic "dynamic simulation tool" 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
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1

Simulation Tools  

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

Building simulation tool screen capture Building simulation tool screen capture Simulation Tools Researchers develop whole-building energy simulation software programs that allow architects and building engineers to design or retrofit buildings for maximum energy efficiency and occupant comfort. Programs developed by researchers include: the EnergyPlus whole building simulation program, the Modelica Buildings library for rapid prototyping and controls design, the Building Controls Virtual Test Bed for co-simulation and for model-based operation, and the GenOpt generic optimization program. Contacts Philip Haves PHaves@lbl.gov (510) 486-6512 Michael Wetter MWetter@lbl.gov (510) 486-6990 Links Simulation Research Group Batteries and Fuel Cells Buildings Energy Efficiency Applications Commercial Buildings

2

An Analysis Tool for Flight Dynamics Monte Carlo Simulations  

E-Print Network [OSTI]

and analysis work to understand vehicle operating limits and identify circumstances that lead to mission failure. A Monte Carlo simulation approach that varies a wide range of physical parameters is typically used to generate thousands of test cases...

Restrepo, Carolina 1982-

2011-05-20T23:59:59.000Z

3

Automating Dynamic Decoupling in Object-Oriented Modelling and Simulation Tools  

E-Print Network [OSTI]

a Modelica transla- tor. Simulation tests demonstrate the technique, and the re- alised implementation than of simulation theory. In this work we refer as "EOO Modelling Tool" to a Modelica translator, to allow exemplifying the (more general) presented ideas. For a Modelica translator, the EOO modelling

Como, Giacomo

4

Developing an integrated building design tool by coupling building energy simulation and computational fluid dynamics programs  

E-Print Network [OSTI]

Building energy simulation (ES) and computational fluid dynamics (CFD) can play important roles in building design by providing essential information to help design energy-efficient, thermally comfortable and healthy ...

Zhai, Zhiqiang, 1971-

2003-01-01T23:59:59.000Z

5

Molecular dynamics simulation: a tool for exploration and discovery using simple models  

E-Print Network [OSTI]

Emergent phenomena share the fascinating property of not being obvious consequences of the design of the system in which they appear. This characteristic is no less relevant when attempting to simulate such phenomena, given that the outcome is not always a foregone conclusion. The present survey focuses on several simple model systems that exhibit surprisingly rich emergent behavior, all studied by MD simulation. The examples are taken from the disparate fields of fluid dynamics, granular matter and supramolecular self-assembly. In studies of fluids modeled at the detailed microscopic level using discrete particles, the simulations demonstrate that complex hydrodynamic phenomena in rotating and convecting fluids, the Taylor-Couette and Rayleigh-B\\'enard instabilities, can not only be observed within the limited length and time scales accessible to MD, but even quantitative agreement can be achieved. Simulation of highly counterintuitive segregation phenomena in granular mixtures, again using MD methods, but now augmented by forces producing damping and friction, leads to results that resemble experimentally observed axial and radial segregation in the case of a rotating cylinder, and to a novel form of horizontal segregation in a vertically vibrated layer. Finally, when modeling self-assembly processes analogous to the formation of the polyhedral shells that package spherical viruses, simulation of suitably shaped particles reveals the ability to produce complete, error-free assembly, and leads to the important general observation that reversible growth steps contribute to the high yield. While there are limitations to the MD approach, both computational and conceptual, the results offer a tantalizing hint of the kinds of phenomena that can be explored, and what might be discovered when sufficient resources are brought to bear on a problem.

D. C. Rapaport

2014-11-13T23:59:59.000Z

6

FASTBUS simulation tools  

SciTech Connect (OSTI)

A generalized model of a FASTBUS master is presented. The model is used with simulation tools to aid in the specification, design, and production of FASTBUS slave modules. The model provides a mechanism to interact with the electrical schematics and software models to predict performance. The model is written in the IEEE std 1076-1987 hardware description language VHDL. A model of the ATC logic is also presented. VHDL was chosen to provide portability to various platforms and simulation tools. The models, in conjunction with most commercially available simulators, will perform all of the transactions specified in IEEE std 960-1989. The models may be used to study the behavior of electrical schematics and other software models and detect violations of the FASTBUS protocol. For example, a hardware design of a slave module could be studied, protocol violations detected and corrected before committing money to prototype development. The master model accepts a stream of high level commands from an ASCII file to initiate FASTBUS transactions. The high level command language is based on the FASTBUS standard routines listed in IEEE std 1177-1989. Using this standard-based command language to direct the model of the master, hardware engineers can simulate FASTBUS transactions in the language used by physicists and programmers to operate FASTBUS systems. 15 refs., 6 figs.

Dean, T.D. (Stanford Linear Accelerator Center, Menlo Park, CA (United States)); Haney, M.J. (Illinois Univ., Urbana, IL (United States))

1991-10-01T23:59:59.000Z

7

Calibration and Validation of a Spar-Type Floating Offshore Wind Turbine Model using the FAST Dynamic Simulation Tool: Preprint  

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

Calibration and Validation of a Calibration and Validation of a Spar-Type Floating Offshore Wind Turbine Model using the FAST Dynamic Simulation Tool Preprint J.R. Browning University of Colorado-Boulder J. Jonkman and A. Robertson National Renewable Energy Laboratory A.J. Goupee University of Maine Presented at the Science of Making Torque from Wind Oldenburg, Germany October 9-11, 2012 Conference Paper NREL/CP-5000-56138 November 2012 NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC (Alliance), a contractor of the US Government under Contract No. DE-AC36-08GO28308. Accordingly, the US Government and Alliance retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes.

8

Mixed Mode Simulation Tools  

E-Print Network [OSTI]

with the whole building modeling tool, but the details ofused (e.g. whole building energy modeling or CAD tool),guide to modeling NV and MM buildings in the research or

Gandhi, Priya; Brager, Gail; Dutton, Spencer

2014-01-01T23:59:59.000Z

9

Mixed Mode Simulation Tools  

E-Print Network [OSTI]

M. (2011). Assessment of natural and hybrid ventilationTools in the Assessment of Hybrid Natural/Mechanical

Gandhi, Priya; Brager, Gail; Dutton, Spencer

2014-01-01T23:59:59.000Z

10

Mixed Mode Simulation Tools  

E-Print Network [OSTI]

ANSYS CFX, ANSYS Fluent, Autodesk Simulation CFD (formerly CFDesign), Autodesk Vasari, FloVENT, Flowdesigner,

Gandhi, Priya; Brager, Gail; Dutton, Spencer

2014-01-01T23:59:59.000Z

11

Dynamic Positioning Simulator Dynamic Positioning Simulator  

E-Print Network [OSTI]

Simulator 5 / 24 #12;Dynamic Positioning Simulator Dynamic Positioning Why Dynamic Positioning? Advantages Dynamic Positioning: No tugboats needed; Offshore set-up is quick; Power saving; Precision situations more on Ship: Wind Force Fw = 1 2 air V 2 rw CXw (rw )AT 1 2 air V 2 rw CYw (rw )AL Mw = 1 2 air V 2 rw CMw (rw

Vuik, Kees

12

Incorporating LCA tools in integrated simulation environments  

E-Print Network [OSTI]

and Meil, J. K. , "ATHENA™: An LCA Decision Support Tool -in the Proceedings. INCORPORATING LCA TOOLS IN INTEGRATEDof Energy. INCORPORATING LCA TOOLS IN INTEGRATED SIMULATION

Pal, Vineeta; Papamichael, Konstantinos; Bourassa, Norman; Loffeld, John J.

2001-01-01T23:59:59.000Z

13

Terascale Simulation Tools and Technologies  

SciTech Connect (OSTI)

We report the development of front tracking method as a simulation tool and technology for the computation on several important SciDAC and SciDAC associated applications. The progress includes the extraction of an independent software library from the front tracking code, conservative front tracking, applications of front tracking to the simulation of fusion pellet injection in a magnetically confined plasma, the study of a fuel injection jet, and the study of fluid chaotic mixing, among other problems.

Li, Xiaolin

2007-03-09T23:59:59.000Z

14

The Xygra gun simulation tool.  

SciTech Connect (OSTI)

Inductive electromagnetic launchers, or coilguns, use discrete solenoidal coils to accelerate a coaxial conductive armature. To date, Sandia has been using an internally developed code, SLINGSHOT, as a point-mass lumped circuit element simulation tool for modeling coilgun behavior for design and verification purposes. This code has shortcomings in terms of accurately modeling gun performance under stressful electromagnetic propulsion environments. To correct for these limitations, it was decided to attempt to closely couple two Sandia simulation codes, Xyce and ALEGRA, to develop a more rigorous simulation capability for demanding launch applications. This report summarizes the modifications made to each respective code and the path forward to completing interfacing between them.

Garasi, Christopher Joseph; Lamppa, Derek C.; Aubuchon, Matthew S.; Shirley, David Noyes; Robinson, Allen Conrad; Russo, Thomas V.

2008-12-01T23:59:59.000Z

15

Autonomie Automotive Simulation Tool | Open Energy Information  

Open Energy Info (EERE)

Autonomie Automotive Simulation Tool Autonomie Automotive Simulation Tool Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Autonomie Automotive Simulation Tool Agency/Company /Organization: Argonne National Laboratory Focus Area: Economic Development, Vehicles Phase: Create a Vision Topics: Pathways analysis Resource Type: Software/modeling tools User Interface: Desktop Application Website: www.transportation.anl.gov/modeling_simulation/PSAT/autonomie.html OpenEI Keyword(s): Energy Efficiency and Renewable Energy (EERE) Tools Language: English References: Autonomie[1] Rapidly evaluate new powertrain and propulsion technologies for improving fuel economy through virtual design and analysis in a math-based simulation environment. Argonne has developed a new tool, called Autonomie, to accelerate the

16

Next generation computational tools for extreme-scale simulation of dynamic fracture and fragmentation in three dimensions  

E-Print Network [OSTI]

The accurate modeling of dynamic fracture and fragmentation remains one of the most difficult challenges in computational mechanics research. As part of this thesis, a scalable algorithm for modeling dynamic fracture and ...

Seagraves, Andrew Nathan

2013-01-01T23:59:59.000Z

17

Optimization of naïve dynamic binary instrumentation Tools/  

E-Print Network [OSTI]

The proliferation of dynamic program analysis tools has done much to ease the burden of developing complex software. However, creating such tools remains a challenge. Dynamic binary instrumentation frameworks such as ...

Kleckner, Reid (Reid N.)

2011-01-01T23:59:59.000Z

18

LLNL-CONF-555171 Simulation Tools  

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

government or Lawrence Livermore National Security, LLC, and shall not be used for advertising or product endorsement purposes. Simulation Tools for Modeling Thermal Spallation...

19

2013 IREP Symposium-Bulk Power System Dynamics and Control IX (IREP), August 25-30, 2013, Rethymnon, Greece A Production Simulation Tool for Systems with an Integrated Concentrated Solar  

E-Print Network [OSTI]

, Rethymnon, Greece A Production Simulation Tool for Systems with an Integrated Concentrated Solar Plant2013 IREP Symposium-Bulk Power System Dynamics and Control ­IX (IREP), August 25-30, 2013 with Thermal Energy Storage Ti Xu George Gross University of Illinois at Urbana-Champaign University

Gross, George

20

Radiation in molecular dynamic simulations  

SciTech Connect (OSTI)

Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of Megabars to thousands of Gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The new technique passes a key test: it relaxes to a blackbody spectrum for a plasma in local thermodynamic equilibrium. This new tool also provides a method for assessing the accuracy of energy and momentum exchange models in hot dense plasmas. As an example, we simulate the evolution of non-equilibrium electron, ion, and radiation temperatures for a hydrogen plasma using the new molecular dynamics simulation capability.

Glosli, J; Graziani, F; More, R; Murillo, M; Streitz, F; Surh, M

2008-10-13T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

DLFM library tools for large scale dynamic applications.  

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

DLFM library tools for large scale dynamic applications DLFM library tools for large scale dynamic applications Large scale Python and other dynamic applications may spend huge...

22

2005-3-21 1 Dynamic Equipment and Process Simulation  

E-Print Network [OSTI]

, reduced order) Simulation-based technology, manufacturing and ESH Metrics Current physical and chemical understanding Simulation ToolDynamic behavior through process cycle Verification Guidelines for equipment) · Gas phase transport · Reactant adsorption and byproduct desorption · Surface

Rubloff, Gary W.

23

Dynamic simulation of Odoo  

Science Journals Connector (OSTI)

Abstract The thermal habits of Odoo were examined and energy consumption data were also predicted. Special tests were performed for the time of the competition, and whole year was also analysed. The climatic data were of Madrid as the competition took place there. The modelling environment was MATLAB's Simulink with a built-in module of Simscape. It is for especially examining thermal behaviours. MATLAB itself is capable of solving differential equations by time, for this reason dynamic simulations can be performed. First the building structure was created, and then the heatflows affecting the internal temperature were added. In this paper detailed process of creating the model is presented, and some results are discussed, including some possibilities of further improvements.

Gábor Haas-Schnabel; Csaba Szikra

2014-01-01T23:59:59.000Z

24

CNC Machine Tool's Wear Diagnostic and Prognostic by Using Dynamic Bayesian Networks  

E-Print Network [OSTI]

CNC Machine Tool's Wear Diagnostic and Prognostic by Using Dynamic Bayesian Networks D.A. Tobon of the health condition of a Computer Numerical Control (CNC) tool machine and the estimation of its Remaining of a CNC tool. Simulation results are obtained and discussed at the end of the paper. Keywords: Diagnostic

Paris-Sud XI, Université de

25

A Groundwater Dynamic Simulation Model: Application to the Upper San Pedro Basin  

E-Print Network [OSTI]

A Groundwater Dynamic Simulation Model: Application to the Upper San Pedro Basin Report Prepared by using tools such as tracers to determine groundwater travel times and this dynamic simulation modeling

Fay, Noah

26

Modeling Molecular Dynamics from Simulations  

SciTech Connect (OSTI)

Many important processes in biology occur at the molecular scale. A detailed understanding of these processes can lead to significant advances in the medical and life sciences. For example, many diseases are caused by protein aggregation or misfolding. One approach to studying these systems is to use physically-based computational simulations to model the interactions and movement of the molecules. While molecular simulations are computationally expensive, it is now possible to simulate many independent molecular dynamics trajectories in a parallel fashion by using super- or distributed- computing methods such as Folding@Home or Blue Gene. The analysis of these large, high-dimensional data sets presents new computational challenges. In this seminar, I will discuss a novel approach to analyzing large ensembles of molecular dynamics trajectories to generate a compact model of the dynamics. This model groups conformations into discrete states and describes the dynamics as Markovian, or history-independent, transitions between the states. I will discuss why the Markovian state model (MSM) is suitable for macromolecular dynamics, and how it can be used to answer many interesting and relevant questions about the molecular system. I will also discuss many of the computational and statistical challenges in building such a model, such as how to appropriately cluster conformations, determine the statistical reliability, and efficiently design new simulations.

Hinrichs, Nina Singhal (University of Chicago) [University of Chicago

2009-01-28T23:59:59.000Z

27

Analysis of the influence of tool dynamics in diamond turning  

SciTech Connect (OSTI)

This report describes the progress in defining the role of machine and interface dynamics on the surface finish in diamond turning. It contains a review of literature from conventional and diamond machining processes relating tool dynamics, material interactions and tool wear to surface finish. Data from experimental measurements of tool/work piece interface dynamics are presented as well as machine dynamics for the DTM at the Center.

Fawcett, S.C.; Luttrell, D.E.; Keltie, R.F.

1988-12-01T23:59:59.000Z

28

Accelerated Molecular Dynamics Simulation of Thermal Desorption.  

E-Print Network [OSTI]

??Desorption is a process ubiquitous in phenomena involving surfaces. However, it has rarely been simulated on the molecular level. Molecular dynamics simulation can provide the… (more)

Becker, Kelly

2008-01-01T23:59:59.000Z

29

Improving Dynamic Load and Generator Response Performance Tools  

E-Print Network [OSTI]

induction motors that Improving Dynamic Load and Generatorand Generator Response Performance Tools Another important example reported in the literature, also involving inductionand Generator Response Performance Tools As partial answers to these questions we note that the 20% induction

Lesieutre, Bernard C.

2005-01-01T23:59:59.000Z

30

Improving Dynamic Load and Generator Response PerformanceTools  

SciTech Connect (OSTI)

This report is a scoping study to examine research opportunities to improve the accuracy of the system dynamic load and generator models, data and performance assessment tools used by CAISO operations engineers and planning engineers, as well as those used by their counterparts at the California utilities, to establish safe operating margins. Model-based simulations are commonly used to assess the impact of credible contingencies in order to determine system operating limits (path ratings, etc.) to ensure compliance with NERC and WECC reliability requirements. Improved models and a better understanding of the impact of uncertainties in these models will increase the reliability of grid operations by allowing operators to more accurately study system voltage problems and the dynamic stability response of the system to disturbances.

Lesieutre, Bernard C.

2005-11-01T23:59:59.000Z

31

New Automotive Air Conditioning System Simulation Tool Developed in MATLAB/Simulink  

SciTech Connect (OSTI)

Further improvements in vehicle fuel efficiency require accurate evaluation of the vehicle's transient total power requirement. When operated, the air conditioning (A/C) system is the largest auxiliary load on a vehicle; therefore, accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation software, such as 'Autonomie,' has been used by OEMs to evaluate vehicles' energy performance. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software Matlab/Simulink was used to develop new and more efficient vehicle energy system controls. The various modeling methods used for the new simulation tool are described in detail. Comparison with measured data is provided to demonstrate the validity of the model.

Kiss, T.; Chaney, L.; Meyer, J.

2013-07-01T23:59:59.000Z

32

Building Energy Software Tools Directory: Frame Simulator  

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

Frame Simulator Frame Simulator Frame Simulator logo Frame Simulator makes calculation of the thermal transmittance in windows and building components an extremely easy process. It can be used to: analyze how heat flows through building components and fenestrations estimate surface temperatures and predict condensation problems discover weak points in window frames calculate thermal transmittance Uf and linear conductance Lf2d of any type of window frame as well as the Uw thermal transmittance of entire complex fenestration. Precise simulation of the heat transfer is performed using a two-dimensional numerical method for steady state boundary conditions conforming to ISO 10077-2 (finite elements). Screen Shots Keywords 2D, heat transfer, thermal analysis, thermal transmittance, thermal

33

Co-Simulation Tools for Networked Control Systems  

E-Print Network [OSTI]

, unmanned vehicles, home robotics, distributed virtual environments, power distribution, and building-simulation. The first two tools are extensions to ns-2 called Agent/Plant and NSCSPlant; the third tool integrates and control of the physical world. (right) A networked control system with one controlled system (a.k.a. plant

Branicky, Michael S.

34

A dynamic GIS as an efficient tool for ICZM (Bay of Brest, Western France)? Franoise Gourmelon1  

E-Print Network [OSTI]

A dynamic GIS as an efficient tool for ICZM (Bay of Brest, Western France)? Françoise Gourmelon1- ling the interactions between human activities in a maritime basin. A dynamic GIS is used as a tool are used at several levels: data collection, GIS analysis, mapping, and simulations. The results show

Brest, Université de

35

Sandia National Laboratories: Computational Fluid Dynamics Simulations...  

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

Canal, Yakima Washington Sandia Publishes Five Reports on the Environmental Effects of Wave-Energy Converters Computational Fluid Dynamics Simulations Provide Insight for Rotor...

36

MOLECULAR DYNAMICS SIMULATIONS OF NANOPARTICLE INTERACTIONS.  

E-Print Network [OSTI]

??Molecular dynamics simulations using the Embedded Atom Method were performed to describe the interparticle behavior of two single crystal spherical nickel nanoparticles during compaction based… (more)

Stone, Tonya Williams

2006-01-01T23:59:59.000Z

37

Dynamic Simulators | netl.doe.gov  

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

to Develop Dynamic Simulators for Supercritical Pulverized Coal and Natural Gas Combined Cycle Power Plants A screen shot of the new generic supercritical once-through...

38

Molecular dynamics simulation studies of electrolytes andelectrolyte...  

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

Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. es40smith.pdf More Documents & Publications Molecular Dynamics Simulation Studies of...

39

DEMAND SIMULATION FOR DYNAMIC TRAFFIC ASSIGNMENT  

E-Print Network [OSTI]

of the response of travelers to real-time pre- trip information. The demand simulator is an extension of dynamicDEMAND SIMULATION FOR DYNAMIC TRAFFIC ASSIGNMENT Constantinos Antoniou, Moshe Ben-Akiva, Michel Bierlaire, and Rabi Mishalani Massachusetts Institute of Technology, Cambridge, MA 02139 Abstract

Bierlaire, Michel

40

Fully-Coupled Simulations of the Rotorcraft / Ship Dynamic Interface Emre Alpman  

E-Print Network [OSTI]

representation of the effect of ship deck on the rotor wake (simplified ground effectFully-Coupled Simulations of the Rotorcraft / Ship Dynamic Interface Emre Alpman exa152@psu A fully- coupled simulation tool has been developed to analyze the rotorcraft/ship dynamic interface

Note: This page contains sample records for the topic "dynamic simulation tool" 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

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND  

E-Print Network [OSTI]

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND FRAGMENTATION OF BRITTLE element simulations of dynamic fracture and fragmentation of brittle solids are presented. Fracture the results of massively parallel numerical simulations of dynamic fracture and fragmentation in brittle

Barr, Al

42

Model Validation with Hybrid Dynamic Simulation  

SciTech Connect (OSTI)

Abstract—Model validation has been one of the central topics in power engineering studies for years. As model validation aims at obtaining reasonable models to represent actual behavior of power system components, it has been essential to validate models against actual measurements or known benchmark behavior. System-wide model simulation results can be compared with actual recordings. However, it is difficult to construct a simulation case for a large power system such as the WECC system and to narrow down to problematic models in a large system. Hybrid dynamic simulation with its capability of injecting external signals into dynamic simulation enables rigorous comparison of measurements and simulation in a small subsystem of interest. This paper presents such a model validation methodology with hybrid dynamic simulation. Two application examples on generator and load model validation are presented to show the validity of this model validation methodology. This methodology is further extended for automatic model validation and dichotomous subsystem model validation.

Huang, Zhenyu; Kosterev, Dmitry; Guttromson, Ross T.; Nguyen, Tony B.

2006-06-18T23:59:59.000Z

43

QUICKSILVER - a general tool for electromagnetic PIC simulation  

SciTech Connect (OSTI)

The dramatic increase in computational capability that has occurred over the last ten years has allowed fully electromagnetic simulations of large, complex, three-dimensional systems to move progressively from impractical, to expensive, and recently, to routine and widespread. This is particularly true for systems that require the motion of free charge to be self-consistently treated. The QUICKSILVER electromagnetic Particle-In-Cell (EM-PIC) code has been developed at Sandia National Laboratories to provide a general tool to simulate a wide variety of such systems. This tool has found widespread use for many diverse applications, including high-current electron and ion diodes, magnetically insulated power transmission systems, high-power microwave oscillators, high-frequency digital and analog integrated circuit packages, microwave integrated circuit components, antenna systems, radar cross-section applications, and electromagnetic interaction with biological material. This paper will give a brief overview of QUICKSILVER and provide some thoughts on its future development.

Seidel, D.B.; Coats, R.S.; Johnson, W.A. [and others

1996-10-01T23:59:59.000Z

44

Visualizations and Simulations from the Center for Simulation of Dynamic Response of Materials (ASC/ASAP)  

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

In Phase 1 of the ASC/ASAP program, The Caltech Center for Simulation of Dynamic Response of Materials developed a proof of concept for a Virtual shock physics Test Facility (VTF) in which the full three-dimensional response of a variety of target materials can be simulated for a wide range of compressive, tensional, and shear loadings, including those produced by detonation of energetic materials. The VTF is being applied to a series of integrated multiphysics simulations each with direct relevance to fundamental scientific issues in the dynamic response of materials that in turn are directly connected to proposed and existing experiments. New generations of multiscale models and terascale simulations are being created. The ASC/ASAP Gallery provides access to visualizations in the areas of materials, fluids, solids, and those related to the VTF. A section of tools and resources is available, as well as the full text of a long list of graphics-rich publications.

45

Molecular Dynamics Simulations of Supported Pt Nanoclusters  

E-Print Network [OSTI]

¤Introduction and Background ¤Constructing a Physical Model ¤Details of the Simulation ¤Results and Conclusions · Petroleum reformation · Gasification of biomass for biofuels #12;Previous Investigation of NanoclustersMolecular Dynamics Simulations of Supported Pt Nanoclusters Jeffrey Moore #12;A Brief Outline

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

46

Dynamics Simulation in a Wave Environment  

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

Coupled Dynamic Simulation in a Wave Coupled Dynamic Simulation in a Wave Environment (Navatek, AEGIR, and WECs) Marine and Hydrokinetics Instrumentation Workshop 9 July 2012 David Kring, Navatek Ltd. Presentation Overview * Introduction to Navatek * AEGIR brief: resistance, seakeeping, global and local loads a 3D, NURBS-based, high-order, Rankine boundary element method ... from same lab as at MIT as WAMIT and SWAN, with pFFT acceleration coupling with controls, structures, aerodynamics, power take-offs * Some WEC applications at Navatek 2 Honolulu, Hawaii, USA Company Background A "Research Shipyard" based in Honolulu, HI Combining simulation-based design with prototype construction

47

Physical simulation study of dynamic voltage instability  

SciTech Connect (OSTI)

This paper presents a physical simulation of the dynamic behavior of voltage instability in an interconnected multimachine environment. The dynamic evolving process leading to eventual voltage collapse, the scenario of the progressive reactive support reduction resulting from the MXL protection relays, the OLTC operation, and the effect of switched-in capacitor banks are examined using physical facilities in the laboratory. The physical simulation results are also compared with digital simulation results. This physical investigation provides a reliable foundation for the effective development of assessment approaches and countermeasures.

Tso, S.K.; Zhu, T.X. [Univ. of Hong Kong (Hong Kong); Zeng, Q.Y. [Electric Power Research Inst., Beijing (China); Lo, K.L. [Univ. of Strathclyde, Glasgow (United Kingdom). Dept. of Electrical and Electrical Engineering

1995-12-31T23:59:59.000Z

48

Selector: A tool for dynamic service selection and management  

E-Print Network [OSTI]

-awareness while discovering and selecting web service. The main idea of the proposed web service oriented architecture consists in the ontology Context-aware Quality Semantic Web Service called (CxQWS). At the firstSelector: A tool for dynamic service selection and management ALTI Adel, BOUKERRAM Abdallah, ROOSE

Paris-Sud XI, Université de

49

SciTech Connect: Development of CFD-Based Simulation Tools for...  

Office of Scientific and Technical Information (OSTI)

Development of CFD-Based Simulation Tools for In-Situ Thermal Processing of Oil ShaleSands Citation Details In-Document Search Title: Development of CFD-Based Simulation Tools for...

50

New Simulation Tool Could Help Add More Solar to the Nation¹s...  

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

Simulation Tool Could Help Add More Solar to the Nations Electric Grid New Simulation Tool Could Help Add More Solar to the Nations Electric Grid April 17, 2014 - 11:26am...

51

Application of Various HVAC Simulation Programs and Visual Tools to Commissioning  

E-Print Network [OSTI]

Various existing HVAC system simulation programs and visualization tools are considered to be potentially powerful tools for commissioning. Although not originally developed as commissioning tools, these programs facilitate the confirmation...

Zheng, M.; Pan, S.

2007-01-01T23:59:59.000Z

52

Simulating the Effect of Modulated Tool-Path Chip Breaking On Surface Texture and Chip Length  

SciTech Connect (OSTI)

One method for creating broken chips in turning processes involves oscillating the cutting tool in the feed direction utilizing the CNC machine axes. The University of North Carolina at Charlotte and the Y-12 National Security Complex have developed and are refining a method to reliably control surface finish and chip length based on a particular machine's dynamic performance. Using computer simulations it is possible to combine the motion of the machine axes with the geometry of the cutting tool to predict the surface characteristics and map the surface texture for a wide range of oscillation parameters. These data allow the selection of oscillation parameters to simultaneously ensure broken chips and acceptable surface characteristics. This paper describes the machine dynamic testing and characterization activities as well as the computational method used for evaluating and predicting chip length and surface texture.

Smith, K.S.; McFarland, J.T.; Tursky, D. A.; Assaid, T. S.; Barkman, W. E.; Babelay, Jr., E. F.

2010-04-30T23:59:59.000Z

53

CgWind: A high-order accurate simulation tool for wind turbines and wind farms  

SciTech Connect (OSTI)

CgWind is a high-fidelity large eddy simulation (LES) tool designed to meet the modeling needs of wind turbine and wind park engineers. This tool combines several advanced computational technologies in order to model accurately the complex and dynamic nature of wind energy applications. The composite grid approach provides high-quality structured grids for the efficient implementation of high-order accurate discretizations of the incompressible Navier-Stokes equations. Composite grids also provide a natural mechanism for modeling bodies in relative motion and complex geometry. Advanced algorithms such as matrix-free multigrid, compact discretizations and approximate factorization will allow CgWind to perform highly resolved calculations efficiently on a wide class of computing resources. Also in development are nonlinear LES subgrid-scale models required to simulate the many interacting scales present in large wind turbine applications. This paper outlines our approach, the current status of CgWind and future development plans.

Chand, K K; Henshaw, W D; Lundquist, K A; Singer, M A

2010-02-22T23:59:59.000Z

54

Westinghouse Waste Simulation and Optimization Software Tool - 13493  

SciTech Connect (OSTI)

Radioactive waste is produced during NPP operation and NPP D and D. Different kinds of waste with different volumes and properties have to be treated. Finding a technically and commercially optimized waste treatment concept is a difficult and time consuming process. The Westinghouse waste simulation and optimization software tool is an approach to study the total life cycle cost of any waste management facility. The tool enables the user of the simulation and optimization software to plan processes and storage buildings and to identify bottlenecks in the overall waste management design before starting detailed planning activities. Furthermore, application of the software enables the user to optimize the number of treatment systems, to determine the minimum design capacity for onsite storage facilities, to identify bottlenecks in the overall design and to identify the most cost-effective treatment paths by maintaining optimal waste treatment technologies. In combination with proven waste treatment equipment and integrated waste management solutions, the waste simulation and optimization software provides reliable qualitative results that lead to an effective planning and minimization of the total project planning risk of any waste management activity. (authors)

Mennicken, Kim [Westinghouse Electric Germany GmbH, Global Waste Management, Dudenstrasse 44, D-68167 Mannheim (Germany)] [Westinghouse Electric Germany GmbH, Global Waste Management, Dudenstrasse 44, D-68167 Mannheim (Germany); Aign, Joerg [Westinghouse Electric Germany GmbH, Global Waste Management, Tarpenring 6, D-22419 Hamburg (Germany)] [Westinghouse Electric Germany GmbH, Global Waste Management, Tarpenring 6, D-22419 Hamburg (Germany)

2013-07-01T23:59:59.000Z

55

VISION - Verifiable Fuel Cycle Simulation of Nuclear Fuel Cycle Dynamics  

SciTech Connect (OSTI)

The U.S. DOE Advanced Fuel Cycle Initiative’s (AFCI) fundamental objective is to provide technology options that - if implemented - would enable long-term growth of nuclear power while improving sustainability and energy security. The AFCI organization structure consists of four areas; Systems Analysis, Fuels, Separations and Transmutations. The Systems Analysis Working Group is tasked with bridging the program technical areas and providing the models, tools, and analyses required to assess the feasibility of design and deployment options and inform key decision makers. An integral part of the Systems Analysis tool set is the development of a system level model that can be used to examine the implications of the different mixes of reactors, implications of fuel reprocessing, impact of deployment technologies, as well as potential "exit" or "off ramp" approaches to phase out technologies, waste management issues and long-term repository needs. The Verifiable Fuel Cycle Simulation Model (VISION) is a computer-based simulation model that allows performing dynamic simulations of fuel cycles to quantify infrastructure requirements and identify key trade-offs between alternatives. It is based on the current AFCI system analysis tool "DYMOND-US" functionalities in addition to economics, isotopic decay, and other new functionalities. VISION is intended to serve as a broad systems analysis and study tool applicable to work conducted as part of the AFCI and Generation IV reactor development studies.

Steven J. Piet; A. M. Yacout; J. J. Jacobson; C. Laws; G. E. Matthern; D. E. Shropshire

2006-02-01T23:59:59.000Z

56

Eddy current NDE performance demonstrations using simulation tools  

SciTech Connect (OSTI)

To carry out performance demonstrations of the Eddy-Current NDE processes applied on French nuclear power plants, EDF studies the possibility of using simulation tools as an alternative to measurements on steam generator tube mocks-up. This paper focuses on the strategy led by EDF to assess and use code{sub C}armel3D and Civa, on the case of Eddy-Current NDE on wears problem which may appear in the U-shape region of steam generator tubes due to the rubbing of anti-vibration bars.

Maurice, L. [EDF - CEIDRE, 2 rue Ampere, 93206 Saint-Denis Cedex 1 (France); Costan, V.; Guillot, E.; Thomas, P. [EDF - R and D, THEMIS, 1, avenue du General de Gaulle, 92141 Clamart (France)

2013-01-25T23:59:59.000Z

57

Dynamic procedure for filtered gyrokinetic simulations  

SciTech Connect (OSTI)

Large eddy simulations (LES) of gyrokinetic plasma turbulence are investigated as interesting candidates to decrease the computational cost. A dynamic procedure is implemented in the gene code, allowing for dynamic optimization of the free parameters of the LES models (setting the amplitudes of dissipative terms). Employing such LES methods, one recovers the free energy and heat flux spectra obtained from highly resolved direct numerical simulations. Systematic comparisons are performed for different values of the temperature gradient and magnetic shear, parameters which are of prime importance in ion temperature gradient driven turbulence. Moreover, the degree of anisotropy of the problem, which can vary with parameters, can be adapted dynamically by the method that shows gyrokinetic large eddy simulation to be a serious candidate to reduce numerical cost of gyrokinetic solvers.

Morel, P.; Banon Navarro, A.; Albrecht-Marc, M.; Carati, D. [Statistical and Plasma Physics Laboratory, Universite Libre de Bruxelles, Bruxelles 1050 (Belgium); Merz, F.; Goerler, T.; Jenko, F. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2012-01-15T23:59:59.000Z

58

Molecular simulation as a tool for studying lignin  

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

Simulation Simulation as a Tool for Studying Lignin Amandeep K. Sangha, a,b Loukas Petridis, a,b Jeremy C. Smith, a,b,c Angela Ziebell, d,e and Jerry M. Parks a,b a UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6309; parksjm@ornl.gov (for correspondence) b BioEnergy Science Center, Oak Ridge, TN c Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, M407 Walters Life Sciences, 1414 Cumberland Avenue, Knoxville, TN 37996 d National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401-3393; angela.ziebell@nrel.gov (for correspondence) e BioEnergy Science Center, Golden, CO Published online 30 December 2011 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ep.10628 Lignocellulosic biomass provides a sustainable source of sugars for biofuel and biomaterial production.

59

A visual simulation playground for engineering dynamics  

E-Print Network [OSTI]

A VISUAL SIMULATION PLAYGROUND FOR ENGINEERING DYNAMICS A Thesis by DONALD BRIAN FONG Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE August 2008 Major... Subject: Visualization Sciences A VISUAL SIMULATION PLAYGROUND FOR ENGINEERING DYNAMICS A Thesis by DONALD BRIAN FONG Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER...

Fong, Donald Brian

2008-10-10T23:59:59.000Z

60

NREL: Dynamic Maps, GIS Data, and Analysis Tools Home Page  

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

The Dynamic Maps, Geographic Information System (GIS) Data and Analysis The Dynamic Maps, Geographic Information System (GIS) Data and Analysis Tools website provides maps, data and tools for renewable energy resources that determine which energy technologies are viable solutions in domestic and international regions. MapSearch - While this site contains detailed information and quality data, if you want to search for the latest and most up-to-date maps created by NREL, please visit our MapSearch: http://www.nrel.gov/gis/mapsearch/ Renewable Energy Technical Potential with the image of a presentation slide with map. The National Renewable Energy Laboratory's GIS team analyzes wind, solar, biomass, geothermal, and other energy resources and inputs the data into the GIS. Read more about how NREL's GIS staff and capabilities enhance the

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Model Validation with Hybrid Dynamic Simulation  

SciTech Connect (OSTI)

Abstract—Model validation has been one of the central topics in power engineering studies for years. As model validation aims at obtaining reasonable models to represent actual behavior of power system components, it has been essential to validate models against actual measurements or known benchmark behavior. System-wide model simulation results can be compared with actual recordings. However, it is difficult to construct a simulation case for a large power system such as the WECC system and to narrow down to problematic models in a large system. Hybrid dynamic simulation with its capability of injecting external signals into dynamic simulation enables rigorous comparison of measurements and simulation in a small subsystem of interest. This paper presents such a model validation methodology with hybrid dynamic simulation. Two application examples on generator and load model validation are presented to show the validity of this model validation methodology. This methodology is further extended for automatic model validation and dichotomous subsystem model validation. A few methods to define model quality indices have been proposed to quantify model error for model validation criteria development.

Huang, Zhenyu; Kosterev, Dmitry; Guttromson, Ross T.; Nguyen, Tony B.

2006-06-22T23:59:59.000Z

62

Battery Lifetime Analysis and Simulation Tool (BLAST) Documentation  

SciTech Connect (OSTI)

The deployment and use of lithium-ion batteries in automotive and stationary energy storage applications must be optimized to justify their high up-front costs. Given that batteries degrade with use and storage, such optimizations must evaluate many years of operation. As the degradation mechanisms are sensitive to temperature, state-of-charge histories, current levels, and cycle depth and frequency, it is important to model both the battery and the application to a high level of detail to ensure battery response is accurately predicted. To address these issues, the National Renewable Energy Laboratory has developed the Battery Lifetime Analysis and Simulation Tool (BLAST) suite of tools. This suite of tools pairs NREL's high-fidelity battery degradation model with a battery electrical and thermal performance model, application-specific electrical and thermal performance models of the larger system (e.g., an electric vehicle), application-specific system use data (e.g., vehicle travel patterns and driving data), and historic climate data from cities across the United States. This provides highly realistic, long-term predictions of battery response and thereby enables quantitative comparisons of varied battery use strategies.

Neubauer, J.

2014-12-01T23:59:59.000Z

63

Building design and thermal renovation measures proposal by means of regression models issued from dynamic simulations  

E-Print Network [OSTI]

comparison between different energy reduction strategies, like improving the insulation levels or increasing the thermal inertia. An example of their use and a data comparison with a dynamic simulation is shown in last;Nowadays, the most reliable solutions to calculate the energy demand are the simulation energy tools

Boyer, Edmond

64

Simulating Field-Scale Soil Organic Carbon Dynamics Using EPIC  

SciTech Connect (OSTI)

Simulation models integrate our knowledge of soil organic C (SOC) dynamics and are useful tools for evaluating impacts of crop management on soil C sequestration; yet, they require local calibration. Our objectives were to calibrate the Environmental Policy Integrated Climate (EPIC) model, and evaluate its performance for simulating SOC fractions as affected by soil landscape and management. An automated parameter optimization procedure was used to calibrate the model for a site-specific experiment in the Coastal Plain of central Alabama. The ability of EPIC to predict corn (Zea mays L.) and cotton (Gossypium hirsutum L.) yields and SOC dynamics on different soil landscape positions (summit, sideslope and drainageway) during the initial period of conservation tillage adoption (5 years) was evaluated using regression and mean squared deviations. Simulated yield explained 88% of measured yield variation, with greatest disagreement on the sideslope position and highest agreement in the drainageway. Simulations explained approximately 1, 34 and 40% of the total variation in microbial biomass C (MBC), particulate organic C (POC) and total organic C (TOC), respectively. Lowest errors on TOC simulations (0-20 cm) were found on the sideslope and summit. We conclude that the automated parameterization was generally successful, although further work is needed to refine the MBC and POC fractions, and to improve EPIC predictions of SOC dynamics with depth. Overall, EPIC was sensitive to spatial differences in C fractions that resulted from differing soil landscape positions. The model needs additional refinement for accurate simulations of field-scale SOC dynamics affected by short-term management decisions.

Causarano, Hector J.; Shaw, Joey N.; Franzluebbers, A. J.; reeves, D. W.; Raper, Randy L.; Balkcom, Kipling S.; Norfleet, M. L.; Izaurralde, R Cesar

2007-07-01T23:59:59.000Z

65

Dynamic simulation of a reverse Brayton refrigerator  

SciTech Connect (OSTI)

A test refrigerator based on the modified Reverse Brayton cycle has been developed in the Chinese Academy of Sciences recently. To study the behaviors of this test refrigerator, a dynamic simulation has been carried out. The numerical model comprises the typical components of the test refrigerator: compressor, valves, heat exchangers, expander and heater. This simulator is based on the oriented-object approach and each component is represented by a set of differential and algebraic equations. The control system of the test refrigerator is also simulated, which can be used to optimize the control strategies. This paper describes all the models and shows the simulation results. Comparisons between simulation results and experimental data are also presented. Experimental validation on the test refrigerator gives satisfactory results.

Peng, N.; Xiong, L. Y.; Dong, B.; Liu, L. Q. [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, CAS, Beijing, 100190 (China); Lei, L. L.; Tang, J. C. [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, CAS, Beijing, 100190 China and Graduate University of Chinese Academy of Sciences, Beijing, 100190 (China)

2014-01-29T23:59:59.000Z

66

Dynamic simulation of polyester mooring lines  

E-Print Network [OSTI]

A numerical scheme, known as CABLE3D, originally developed for the simulation of dynamics of steel chain-wire mooring lines is extended to allow for the large elongation in a mooring line, the dependence of the modulus on tension, and energy...

Kim, Min Suk

2004-09-30T23:59:59.000Z

67

Dynamic simulation , 1.1 INTRODUCTION  

E-Print Network [OSTI]

storage tank to prevent flashing in the line. 1.2.2 Propane Storage System Product propane from either receipt as well as product loading. Each of the storage tanks is equipped with one circulation pump Compressor Control system . Dynamic simulation , , , . STEADY STATE

Hong, Deog Ki

68

Molecular dynamics simulation of hydration in myoglobin  

SciTech Connect (OSTI)

This study was carried out to evaluate the stability of the 89 bound water molecules that were observed in the neutron diffraction study of CO myoglobin. The myoglobin structure derived from the neutron analysis was used as the starting point in the molecular dynamics simulation using the software package CHARMM. After salvation of the protein, energy minimization and equilibration of the system, 50 pico seconds of Newtonian dynamics was performed. This data showed that only 4 water molecules are continously bound during the length of this simulation while the other solvent molecules exhibit considerable mobility and are breaking and reforming hydrogen bonds with the protein. At any instant during the simulation, 73 of the hydration sites observed in the neutron structure are occupied by water.

Gu, Wei [New Mexico Univ., Albuquerque, NM (United States). Dept. of Biochemistry; Schoenborn, B.P. [Los Alamos National Lab., NM (United States)

1995-09-01T23:59:59.000Z

69

Uncertainty Quantification Tools for Multiphase Flow Simulations using MFIX  

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

Uncertainty Uncertainty Quantification Tools for Multiphase Flow Simulations using MFIX X. Hu 1 , A. Passalacqua 2 , R. O. Fox 1 1 Iowa State University, Department of Chemical and Biological Engineering, Ames, IA 2 Iowa State University, Department of Mechanical Engineering, Ames, IA Project Manager: Steve Seachman University Coal Research and Historically Black Colleges and Universities and Other Minority Institutions Contractors Review Conference Pittsburgh, June 11 th - 13 th 2013 X. Hu, A. Passalacqua, R. O. Fox (ISU) Uncertainty quantification DOE-UCR Review Meeting 2013 1 / 44 Outline 1 Introduction and background 2 Project objectives and milestones 3 Technical progress Univariate case Multivariate case Code structure 4 Future work X. Hu, A. Passalacqua, R. O. Fox (ISU) Uncertainty quantification DOE-UCR Review Meeting 2013 2 / 44 Introduction and background Outline 1 Introduction

70

Interoperable mesh and geometry tools for advanced petascale simulations  

SciTech Connect (OSTI)

SciDAC applications have a demonstrated need for advanced software tools to manage the complexities associated with sophisticated geometry, mesh, and field manipulation tasks, particularly as computer architectures move toward the petascale. The Center for Interoperable Technologies for Advanced Petascale Simulations (ITAPS) will deliver interoperable and interchangeable mesh, geometry, and field manipulation services that are of direct use to SciDAC applications. The premise of our technology development goal is to provide such services as libraries that can be used with minimal intrusion into application codes. To develop these technologies, we focus on defining a common data model and datastructure neutral interfaces that unify a number of different services such as mesh generation and improvement, front tracking, adaptive mesh refinement, shape optimization, and solution transfer operations. We highlight the use of several ITAPS services in SciDAC applications.

Diachin, L; Bauer, A; Fix, B; Kraftcheck, J; Jansen, K; Luo, X; Miller, M; Ollivier-Gooch, C; Shephard, M; Tautges, T; Trease, H

2007-07-04T23:59:59.000Z

71

Computer Simulation of Quantum Dynamics in a Classical Spin Environment  

E-Print Network [OSTI]

In this paper a formalism for studying the dynamics of quantum systems coupled to classical spin environments is reviewed. The theory is based on generalized antisymmetric brackets and naturally predicts open-path off-diagonal geometric phases in the evolution of the density matrix. It is shown that such geometric phases must also be considered in the quantum-classical Liouville equation for a classical bath with canonical phase space coordinates; this occurs whenever the adiabatics basis is complex (as in the case of a magnetic field coupled to the quantum subsystem). When the quantum subsystem is weakly coupled to the spin environment, non-adiabatic transitions can be neglected and one can construct an effective non-Markovian computer simulation scheme for open quantum system dynamics in classical spin environments. In order to tackle this case, integration algorithms based on the symmetric Trotter factorization of the classical-like spin propagator are derived. Such algorithms are applied to a model comprising a quantum two-level system coupled to a single classical spin in an external magnetic field. Starting from an excited state, the population difference and the coherences of this two-state model are simulated in time while the dynamics of the classical spin is monitored in detail. It is the author's opinion that the numerical evidence provided in this paper is a first step toward developing the simulation of quantum dynamics in classical spin environments into an effective tool. In turn, the ability to simulate such a dynamics can have a positive impact on various fields, among which, for example, nano-science.

Alessandro Sergi

2014-04-24T23:59:59.000Z

72

A versatile simulation tool for the design and verification of military vehicle power systems  

E-Print Network [OSTI]

modes of operation and system scenarios) and system performance in a dynamic, realistic environment. This thesis proposes a new tool to analyze and design military vehicle platforms: the Advanced Mobile Integrated Power System (AMPS). This tool is useful...

Lipscomb, Melissa Anne

2005-11-01T23:59:59.000Z

73

Physics results from dynamical overlap fermion simulations  

E-Print Network [OSTI]

I summarize the physics results obtained from large-scale dynamical overlap fermion simulations by the JLQCD and TWQCD collaborations. The numerical simulations are performed at a fixed global topological sector; the physics results in the theta-vacuum is reconstructed by correcting the finite volume effect, for which the measurement of the topological susceptibility is crucial. Physics applications we studied so far include a calculation of chiral condensate, pion mass, decay constant, form factors, as well as (vector and axial-vector) vacuum polarization functions and nucleon sigma term.

Shoji Hashimoto

2008-11-08T23:59:59.000Z

74

Molecular dynamics simulation and ab intio studies of electrolytes...  

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

Molecular dynamics simulations: Properties of bulk electrolytes (structure, thermodynamics, transport), interfacial properties of electrolyte at electroactive interfaces,...

75

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

76

The Quick Energy Simulation Tool (eQUEST) | Open Energy Information  

Open Energy Info (EERE)

The Quick Energy Simulation Tool (eQUEST) The Quick Energy Simulation Tool (eQUEST) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: eQUEST Agency/Company /Organization: James J. Hirsh & Associates Partner: Lawrence Berkeley National Laboratory (LBNL) Sector: Energy Focus Area: Energy Efficiency, Buildings Phase: Create a Vision, Evaluate Options, Develop Goals, Prepare a Plan Resource Type: Software/modeling tools User Interface: Desktop Application Website: doe2.com/equest/ Cost: Free References: eQUEST[1] The Quick Energy Simulation Tool, or eQUEST, allows users with limited simulation experience to develop 3-dimensional simulation models of a particular building design. These simulations incorporate building location, orientation, wall/roof construction, window properties, as well

77

IGCC Dynamic Simulator and Training Center  

SciTech Connect (OSTI)

Integrated Gasification Combined Cycle (IGCC) is emerging as the technology of choice for providing clean, low-cost electricity for the next generation of coal-fired power plants and will play a central role in the development of high-efficiency, zero-emissions power plants such as FutureGen. Several major utilities and developers recently announced plans to build IGCC plants and other major utilities are evaluating IGCC’s suitability for base-load capacity additions. This recent surge of attention to IGCC power generation is creating a growing demand for experience with the analysis, operation, and control of commercial-scale IGCC plants. To meet this need, the National Energy Technology Laboratory (NETL) has launched a project to develop a generic, full-scope, IGCC dynamic plant simulator for use in establishing a state-of-the-art simulator training center at West Virginia University’s (WVU) National Research Center for Coal and Energy (NRCCE). The IGCC Dynamic Simulator & Training (DS&T) Center will be established under the auspices of the Collaboratory for Process & Dynamic Systems Modeling (“Collaboratory”) organized between NETL, WVU, the University of Pittsburgh, and Carnegie Mellon University.

Zitney, S.E.; Erbes, M.R. (Enginomix, LLC)

2006-10-01T23:59:59.000Z

78

NREL Developing a Numerical Simulation Tool to Study Hydrokinetic Energy Conversion Devices and Arrays (Fact Sheet)  

SciTech Connect (OSTI)

New code will help accelerate design improvements by providing a high-fidelity simulation tool to study power performance, structural loading, and the interactions between devices in arrays.

Not Available

2012-02-01T23:59:59.000Z

79

Summary - System Level Modeling and Simulation Tools for SRS  

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

Workflo Workflo The ob Proces Savann Dispos assess evaluat design evaluat predict to guid * Th so in w es sy * Th is m * Th fle m de fu The pu techni projec Site: S roject: S Report Date: J ited States valuation i Why DOE ow Diagram bjective of the rev ss Simulation To nah River Site (S sition System Pla s whether the too te methods used , construction, p te methods to im ions; and (4) det e actual executio What th he current Syst oftware tools to formation, and aste. These to stimates, but th ystem planning he capability of limited. This h mid to long-term here is a need exibility, and tu model prediction ecouple safety unctions. To view the full E http://www.em.doe. urpose of an Externa ical risk associated w ct decisions. Technic Savannah Rive SRS System M June 2009 Departmen n of Sys n Suppo E-EM Did This view was to eva

80

Brownian Dynamics Simulation of Protein Solutions: Structural and Dynamical Properties  

SciTech Connect (OSTI)

The study of solutions of biomacromolecules provides an important basis for understanding the behavior of many fundamental cellular processes, such as protein folding, self-assembly, biochemical reactions, and signal transduction. Here, we describe a Brownian dynamics simulation procedure and its validation for the study of the dynamic and structural properties of protein solutions. In the model used, the proteins are treated as atomically detailed rigid bodies moving in a continuum solvent. The protein-protein interaction forces are described by the sum of electrostatic interaction, electrostatic desolvation, nonpolar desolvation, and soft-core repulsion terms. The linearized Poisson-Boltzmann equation is solved to compute electrostatic terms. Simulations of homogeneous solutions of three different proteins with varying concentrations, pH, and ionic strength were performed. The results were compared to experimental data and theoretical values in terms of long-time self-diffusion coefficients, second virial coefficients, and structure factors. The results agree with the experimental trends and, in many cases, experimental values are reproduced quantitatively. There are no parameters specific to certain protein types in the interaction model, and hence the model should be applicable to the simulation of the behavior of mixtures of macromolecules in cell-like crowded environments.

Mereghetti, Paolo; Gabdoulline, Razif; Wade, Rebecca C.

2010-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Nanoparticle coalescence and sintering: molecular dynamics simulation  

Science Journals Connector (OSTI)

Molecular Dynamics (MD) simulations are employed to better understand coalescence and sintering processes of gold nanoparticles. During coalescence in the liquid phase, the initial neck growth can be well described by the viscous flow model. With initial temperature right below the single particle melting temperature, the initial neck growth is controlled by viscous flow at first and then, by grain boundary diffusion. At initial temperatures well below melting, the sintering process occurs very rapidly, which may be attributed to a formation of liquid-like neck regions. The sintering of two free Au nanoparticles irradiated by a femtosecond laser pulse is also simulated by combining the two-temperature and MD models. It is shown that by increasing laser input energy, nanoparticles can be melted forming a single larger nanoparticle. The effects of multinanoparticle melting, solidification and sintering are also investigated.

N. Wang; S.I. Rokhlin; D.F. Farson

2007-01-01T23:59:59.000Z

82

Simulation of systems with dynamically varying model structure  

Science Journals Connector (OSTI)

Hybrid systems are dynamical systems composed of components with discrete and continuous behavior. Some systems change their structure during simulation, or their components behavior is essentially changing. This ''structural dynamics'' can be described ... Keywords: Discrete-continuous simulation, Hybrid systems, Modelica, Structural dynamics, VHDL-AMS

Peter Schwarz

2008-12-01T23:59:59.000Z

83

A New Motorcycle Simulator Platform: Mechatronics Design, Dynamics Modeling  

E-Print Network [OSTI]

A New Motorcycle Simulator Platform: Mechatronics Design, Dynamics Modeling and Control L. Nehaoua of these techniques to other simulators (cars and motorcycles) is possible but not direct. Indeed, the dynamics motorcycle driving simulators were build. The first prototype was developed by Honda in 1988

Paris-Sud XI, Université de

84

DHARMA: A Tool for Evaluating Dynamic Scheduling Algorithms for Realtime Multiprocessor Systems  

E-Print Network [OSTI]

is an attempt towards satisfying such requirements. The tool provides an envir­ onment to study various dynamic discuss our dynamic scheduling and reclaiming algorithms. Section 5 discusses the software architecture

Manimaran, Govindarasu

85

A Dynamic Waste Isolation Pilot Plant Performance Assessment Tool - 12490  

SciTech Connect (OSTI)

The Waste Isolation Pilot Plant (WIPP) Performance Assessment (PA) methodology comprises a toolbox used to demonstrate regulatory compliance of the repository after facility closure. The PA framework rests upon an extensive suite of computational codes. In some cases, significant alteration of code inputs is a tedious and difficult task. Due to the nature of the application for which they are used, PA codes used in support of WIPP regulatory compliance demonstration must satisfy stringent quality assurance requirements. Consequently, many of the coding practices used during original code development are still implemented today. A more efficient workflow configuration has the potential to alleviate difficulties associated with extensive code input modifications. Here, this potential is assessed via an implementation of a more flexible scientific workflow system for a subset of the codes used in WIPP PA. The scientific workflow approach taken here for a dynamic PA system enables users from disparate backgrounds to dramatically shorten the time between hypothesis and analysis by decreasing the amount of a priori knowledge, from a range of disciplines, needed to execute the code. Having smaller iteration times allows for more ideas to be tested and explored, which leads to safer and more optimized systems. Note that these high-level, dynamic tools are intended only for initial scoping studies on the personal computer of a researcher. Full, regulatory compliance calculations may occur only within a qualified computing environment. However, the WIPP PA tools here may guide future research and indicate regions of the analysis space that are worth further study. This next generation of PA software provides the ability to perform scoping investigations of repository performance quickly and easily, and has an accessible and useful interface to a variety of users, such as fuel cycle systems designers, domain experts such as repository modelers, and policy makers. The purview of this project allows for many opportunities for future work. Foremost among these is the desire to implement the full BRAGFLO suite within the workflow. This will entail porting or wrapping Genmesh, Matset, LHS, and ICSet within Python. Moreover, unifying the two GUIs into a single driver application would be a natural next step. Once the BRAGFLO suite is completed, other portions of WIPP PA could be implemented with corresponding and inter-operable work-flows. Likely first candidates for this are those codes that are similarly computationally intensive, such as the one used to generate complementary cumulative distribution functions used to demonstrate regulatory compliance (code CCDFGF). (authors)

Scopatz, Anthony M.; March, Jonathan; Weckesser, Warren; Jones, Eric [Enthought Inc, Austin, Texas, 78701 (United States); Lee, Moo; Camphouse, Chris [Sandia National Laboratories, Carlsbad, NM, 88220 (United States)

2012-07-01T23:59:59.000Z

86

Development of CFD-Based Simulation Tools for In-Situ Thermal Processing of Oil Shale/Sands  

SciTech Connect (OSTI)

In our research, we are taking the novel approach of developing and applying high performance computing, computational fluid dynamics (CFD)-based simulation tools to a modified in-situ process for production of oil from oil shale. The simulation tools being developed capture the relevant physical processes and data from a large-scale system. The modified in-situ application is a pilot-scale heat transfer process inside Red Leaf Resourcesâ?? EcoShale capsule. We demonstrate the need to understand fluid flow behavior in the convective channels of the rubblized shale bed as convective heating greatly decreases the time required to heat the oil shale to the production temperature when compared with conductive heating alone. We have developed and implemented a geometry creation strategy for a representative section of the EcoShale capsule, developed a meshing approach to deal with the complicated geometry and produce a well-behaved mesh, analyzed the effects of boundary conditions on the simulation results, and devised a new operator splitting solution algorithm that reduces computational costs by taking advantage of the differing convective and conductive time scales occurring in the simulation. These simulation tools can be applied to a wide range of processes involving convective fluid flow heating in rubblized beds.

None

2012-04-30T23:59:59.000Z

87

A Quasi-Dynamic HVAC and Building Simulation Methodology  

E-Print Network [OSTI]

This thesis introduces a quasi-dynamic building simulation methodology which complements existing building simulators by allowing transient models of HVAC (heating, ventilating and air-conditioning) systems to be created in an analogous way...

Davis, Clinton Paul

2012-07-16T23:59:59.000Z

88

Avestar® - Integrated Gasification Combined Cycle (IGCC) Dynamic Simulator  

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

Integrated Gasification Combined Cycle (IGCC) Dynamic Simulator Integrated Gasification Combined Cycle (IGCC) Dynamic Simulator The AVESTAR® center offers courses using the Integrated Gasification Combined Cycle (IGCC) Dynamic Simulator. The IGCC simulator builds on and reaches beyond existing combined-cycle and conventional-coal power plant simulators to combine--for the first time--a Gasification with CO2 Capture process simulator with a Combined-Cycle power simulator together in a single dynamic simulation framework. The AVESTAR® center IGCC courses provide unique, comprehensive training on all aspects of an IGCC plant, illustrating the high-efficiency aspects of the gasifier, gas turbine, and steam turbine integration. IGCC Operator training station HMI display for overview of IGCC Plant - Train A Reference:

89

Services inside the Smart Home A Simulation and Visualization tool  

E-Print Network [OSTI]

SketchUp (http://sketchup.google.com) with a set of tools that extend its visual representation as a set of plug-ins for Google SketchUp, the communication mechanism is based on the Ruby SOAP

Aiello, Marco

90

Molecular dynamics simulations of osmosis and reverse osmosis in solutions  

Science Journals Connector (OSTI)

Computer simulation studies using the method of molecular dynamics have been carried out to investigate osmosis and reverse osmosis in solutions separated by semi-permeable membranes....

S. Murad

1996-01-01T23:59:59.000Z

91

Molecular dynamics simulation and ab intio studies of electrolytes...  

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

Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation es058smith2011o.pdf More Documents & Publications Molecular Dynamics Simulation Studies of...

92

Springback Simulation of High Strength Steel Sheet using Local Interpolation for Tool Surfaces  

SciTech Connect (OSTI)

This paper presents the effect of tool modelling accuracy on the simulation accuracy of springback in high strength steels. Simulations of a two-dimensional draw-bending process are carried out by using a polyhedral tool model whose surface is approximated by a polyhedron, and a model whose surface is smoothed by quadratic parametric surfaces proposed by Nagata [Nagata, Comput. Aided Geom. D, 22(2005), 55-59] (Nagata patch model). It is found that not only the shape accuracy but also the normal vector accuracy of tool models are of importance for accurate springback predictions. The use of the Nagata patch model is an efficient approach not only to improve the simulation accuracy but also to make the simulation be hardly influenced by the tool mesh, even for simulations of a high strength steel in which large amount of springback is involved.

Hama, Takayuki; Fujimoto, Hitoshi; Takuda, Hirohiko [Department of Energy Science and Technology, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Teodosiu, Cristian [Volume-CAD System Research Program, The Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan); LPMTM-CNRS, University Paris 13, 93430 Villetaneuse (France); Makinouchi, Akitake [Volume-CAD System Research Program, The Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan)

2007-05-17T23:59:59.000Z

93

Object-oriented modelling and simulation for the ALFRED dynamics  

Science Journals Connector (OSTI)

Abstract In this paper, a control-oriented modelling and simulation tool for the study of the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED) plant dynamics is presented. It has been developed in order to perform design-basis transient analyses aimed at providing essential feedbacks for the system design finalization. The simulator has been meant to be modular, open and efficient. In this perspective, an object-oriented modelling approach has been adopted, by employing the reliable, tested and well-documented Modelica language. Simulation of core behaviour is based on point kinetics for neutronics and one-dimensional heat transfer models for thermal-hydraulics, coherently with ALFRED specifications. An effort has been spent to model the bayonet-tube Steam Generator (SG) foreseen to be installed within the reactor vessel. The primary loop model has been built by connecting the above-mentioned components (taking into account suitable time delays) and by incorporating the cold pool, which has revealed to be fundamental for an accurate definition of the time constants characteristic of the system because of its large thermal inertia. The description of the overall plant has been finalized by connecting standard turbine, condenser and other components of the balance of plant. Afterwards, the reactor responses to three typical transient initiators have been simulated (i.e., reduction of feedwater mass flow rate, variation of the turbine admission valve coefficient and transient of overpower). Simulation outcomes confirm the strong coupling between core and SG, besides showing the characteristic time constants of the various component responses. Results of the present study constitute a starting point in the definition of plant control strategies, laying the basis for investigation and development of a model-based control-system design.

Roberto Ponciroli; Andrea Bigoni; Antonio Cammi; Stefano Lorenzi; Lelio Luzzi

2014-01-01T23:59:59.000Z

94

Towards a reliable and efficient furnace simulation tool for coal fired utility boilers  

Science Journals Connector (OSTI)

A validation exercise is presented with the objective of demonstrating that using a mature furnace simulation tool on high end supercomputers enables the reliable prediction of coal-fired utility boiler perfor...

Benedetto Risio; Uwe Schnell…

1999-01-01T23:59:59.000Z

95

Computer simulation as a NOx reduction design tool  

SciTech Connect (OSTI)

Nalco Mobotec engineers were charged with reducing emissions on a utility boiler converted from burning oil to eastern bituminous coal using the company's Rotamix selective noncatalytic reduction (SNCR) system which injects urea into the furnace. A CFD simulation of the existing boiler was first conducted and then the furnace was simulated with the SNCR system added and the design was optimised. Operating and capital costs were minimised by optimal placement of 50 injector ports. 6 figs., 2 tabs.

Liu, G.; Higgins, B.S. [Nalco Mobotec (United States)

2008-10-15T23:59:59.000Z

96

A PRODUCTION SIMULATION TOOL FOR SYSTEMS WITH INTEGRATED WIND ENERGY RESOURCES  

E-Print Network [OSTI]

A PRODUCTION SIMULATION TOOL FOR SYSTEMS WITH INTEGRATED WIND ENERGY RESOURCES BY NICOLAS BENOIT the energy output of a wind farm in a single location and of those in multiple locations. In this way, we for such planning tools. The incorporation of the wind energy model requires the extension of the widely used

Gross, George

97

Laser shocks: A tool for experimental simulation of damage into materials  

SciTech Connect (OSTI)

High power laser irradiation of solids results in a strong shock wave propagation, driving very high amplitude pressure loadings with very short durations. These particular characteristics offer the possibility to study the behaviour of matter under extreme dynamic conditions in continuity with what is possible with the conventional generators of shock (launchers of projectiles, explosives). An advantage of laser shocks is a possible recovery of the shocked samples presenting the metallurgical effects of the shock in most cases. We introduce the principle of the laser shock generation, the characterization of these shocks, the principal mechanisms and effects associated with their propagation in the solids. We show how laser shocks can be a laboratory tool for simulating shock effects at ultra high strain rate, providing a high in information experimental layout for validation of damage modelling on an extended strain rate range compared to conventional shock generators. New data have been obtained with ultra short femtosecond range irradiation. Experimental data gathered through post mortem observation, time resolved velocity measurement are shown along with numerical associated simulations, showing the possibility to predict the damage behaviour of metallic targets under extreme strain rate up to 10{sup 8} s{sup -1}.

Boustie, M.; Cuq Lelandais, J. P.; Berthe, L.; Ecault, R. [Institut PPRIME, Departement Physique et Mecanique des Materiaux, CNRS-ENSMA-Universite de Poitiers, 1 av Clement Ader, 86961 FUTUROSCOPE Cedex (France); CEA-DAM Valduc, 21120 Is-sur-Tille (France); Laboratoire Procedes et Ingenierie en Mecanique et Materiaux (CNRS), Arts et Metiers ParisTech, 151 bd de l'Hopital, 75013 PARIS (France); Institut PPRIME, Departement Physique et Mecanique des Materiaux, CNRS-ENSMA-Universite de Poitiers, 1 av Clement Ader, 86961 FUTUROSCOPE Cedex (France)

2012-07-30T23:59:59.000Z

98

AVESTAR® - Natural Gas Combined Cycle (NGCC) Dynamic Simulator  

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

Natural Gas Combined Cycle (NGCC) Dynamic Simulator Natural Gas Combined Cycle (NGCC) Dynamic Simulator A simulator that can provide future engineers with realistic, hands-on experience for operating advanced natural gas combined cycle (NGCC) power plants will soon be available at an innovative U.S. Department of Energy training center. Under a new cooperative research and development agreement signed by the Office of Fossil Energy's National Energy Technology Laboratory (NETL) and Invensys Operations Management, the partners will develop, test, and deploy a dynamic simulator and operator training system (OTS) for a generic NGCC power plant equipped for use with post-combustion carbon capture. NETL will operate the new dynamic simulator/OTS at the AVESTAR (Advanced Virtual Energy Simulation Training and Research) Center in Morgantown, W.Va.

99

Development of simulation tools for virus shell assembly. Final report  

SciTech Connect (OSTI)

Prof. Berger's major areas of research have been in applying computational and mathematical techniques to problems in biology, and more specifically to problems in protein folding and genomics. Significant progress has been made in the following areas relating to virus shell assembly: development has been progressing on a second-generation self-assembly simulator which provides a more versatile and physically realistic model of assembly; simulations are being developed and applied to a variety of problems in virus assembly; and collaborative efforts have continued with experimental biologists to verify and inspire the local rules theory and the simulator. The group has also worked on applications of the techniques developed here to other self-assembling structures in the material and biological sciences. Some of this work has been conducted in conjunction with Dr. Sorin Istrail when he was at Sandia National Labs.

Berger, Bonnie

2001-01-05T23:59:59.000Z

100

Tools  

Broader source: Energy.gov [DOE]

The Federal Energy Management Program (FEMP) compiles online tools to help agencies estimate energy savings.

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Annual Report 1999 Environmental Dynamics and Simulation  

SciTech Connect (OSTI)

This annual report describes selected 1999 research accomplishments for the Environmental Dynamics and Simulation (ED and S) directorate, one of six research organizations in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL). These accomplishments are representative of the different lines of research underway in the ED and S directorate. EMSL is one of US Department of Energy's (DOE) national scientific user facilities and is the centerpiece of DOE's commitment to providing world-class experimental, theoretical, and computational capabilities for solving the nation's environmental problems. Capabilities in the EMSL include over 100 major instrument systems for use by the resident research staff, their collaborators, and users of the EMSL. These capabilities are used to address the fundamental science that will be the basis for finding solutions to national environmental issues such as cleaning up contamianted areas at DOE sites across the country and developing green technologies that will reduce or eliminate future pollution production. The capabilities are also used to further the understanding of global climate change and environmental issues relevant to energy production and use and health effects resulting from exposure to contaminated environments.

NS Foster-Mills

2000-06-28T23:59:59.000Z

102

Portable Graphical Tools for Concurrent Plasma Simulation October 18, 1996  

E-Print Network [OSTI]

Conference Plasma Reactor A Standardized Reactor Design for Research Purposes Experimental Model (left Faculty Sponsor: Dr. Stephen Taylor Abstract Low pressure reactors (less than 1.5 Torr) are used for large­scale simulations of these reactors. In order for Hawk to be convenient for the process engineers

103

A Simulation Tool for Real-time Systems using Environmental Energy Harvesting Maryline CHETTO  

E-Print Network [OSTI]

, the system operates in a so-called energy neutral mode by consuming only as much energy as harvested. The simulator enables to construct an optimal schedule for any task set, battery capacity and energy sourceA Simulation Tool for Real-time Systems using Environmental Energy Harvesting Maryline CHETTO

Paris-Sud XI, Université de

104

ECMI2008 Abstract Agent-Based Simulation as a Novel Decision Support Tool for Retail Managers  

E-Print Network [OSTI]

ECMI2008 Abstract Agent-Based Simulation as a Novel Decision Support Tool for Retail Managers Dr Strategy, Learning & Change (LUBS), Leeds, LS2 9JT, UK Abstract: Intelligent agents offer a new and exciting way of understanding the world of work. We apply agent-based simulation to investigate a set

Aickelin, Uwe

105

Summary - System Level Modeling and Simulation Tools for Hanford  

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

The ob The ob curren plannin Dispos yield re to mod plannin to imp (4) det actual * Th th Th co no in pl * In fo op sy as di re de co an * Th en m ha ev sc The pu techni projec Site: H roject: H Report Date: S ited States valuation in Su Why DOE bjective of the r nt Process Simu ng basis for OR sition System P easonable esti del facilities cur ng or operation rove the rate o termine if addit execution of in What th he current Syst hat are limited t hese tools curr omposition, res ot meeting was itial batches. T anning tool tha ncomplete sync or tank farm ope peration (G2 dy ystem analysis ssumptions use fferent. HTWO esults in the sys esign/operation onsequence tim nalyzed. he lack of an "o ntire plant/proc maintainability (R ampers life cyc valuate system cenarios to imp To view the full E http://www.em.doe. urpose of an Externa

106

NREL Evaluates the Thermal Performance of Uninsulated Walls to Improve the Accuracy of Building Energy Simulation Tools (Fact Sheet)  

SciTech Connect (OSTI)

This technical highlight describes NREL research to develop models of uninsulated wall assemblies that help to improve the accuracy of building energy simulation tools when modeling potential energy savings in older homes. Researchers at the National Renewable Energy Laboratory (NREL) have developed models for evaluating the thermal performance of walls in existing homes that will improve the accuracy of building energy simulation tools when predicting potential energy savings of existing homes. Uninsulated walls are typical in older homes where the wall cavities were not insulated during construction or where the insulating material has settled. Accurate calculation of heat transfer through building enclosures will help determine the benefit of energy efficiency upgrades in order to reduce energy consumption in older American homes. NREL performed detailed computational fluid dynamics (CFD) analysis to quantify the energy loss/gain through the walls and to visualize different airflow regimes within the uninsulated cavities. The effects of ambient outdoor temperature, radiative properties of building materials, and insulation level were investigated. The study showed that multi-dimensional airflows occur in walls with uninsulated cavities and that the thermal resistance is a function of the outdoor temperature - an effect not accounted for in existing building energy simulation tools. The study quantified the difference between CFD prediction and the approach currently used in building energy simulation tools over a wide range of conditions. For example, researchers found that CFD predicted lower heating loads and slightly higher cooling loads. Implementation of CFD results into building energy simulation tools such as DOE2 and EnergyPlus will likely reduce the predicted heating load of homes. Researchers also determined that a small air gap in a partially insulated cavity can lead to a significant reduction in thermal resistance. For instance, a 4-in. tall air gap (Figure 1a) led to a 15% reduction in resistance. Similarly, a 2-ft tall air gap (Figure 1c) led to 54% reduction in thermal resistance. NREL researchers plan to extend this study to include additional wall configurations, and also to evaluate the performance of attic spaces with different insulation levels. NREL's objective is to address each potential issue that leads to inaccuracies in building energy simulation tools to improve the predictions.

Not Available

2012-01-01T23:59:59.000Z

107

NREL: Dynamic Maps, GIS Data, and Analysis Tools - Solar Maps  

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

For more PV resource maps, access the MapSearch site. For Geographic Information System (GIS) solar resource data, access the Data Resources page. For interactive maps and tools...

108

Dynamic wind turbine models in power system simulation tool  

E-Print Network [OSTI]

.2.1.2 Doubly-fed induction generator (DFIG) 13 2.2.1.3 Synchronous generator 15 2.2.2 Power converters 18 2

109

CGILua: A MultiParadigmatic Tool for Creating Dynamic WWW Pages  

E-Print Network [OSTI]

CGILua: A Multi­Paradigmatic Tool for Creating Dynamic WWW Pages Anna M. Hester Renato Borges'' to mark fields to be filled in. When the page is accessed, the template feeds a pre­processor that creates

Ierusalimschy, Roberto

110

Urban Pilot : a dynamic mapping tool for personalizing the city through collective memory  

E-Print Network [OSTI]

This thesis investigates the use of handheld mobile devices as exploratory personalized tools for dynamic navigation of the cityscape that go beyond cartographic limitations and yellow-page directory services. One needs ...

Goel, Aradhana, 1972-

2001-01-01T23:59:59.000Z

111

Development of a dynamic simulator for a natural gas combined cycle (NGCC) power plant with post-combustion carbon capture  

SciTech Connect (OSTI)

The AVESTAR Center located at the U.S. Department of Energy’s National Energy Technology Laboratory and West Virginia University is a world-class research and training environment dedicated to using dynamic process simulation as a tool for advancing the safe, efficient and reliable operation of clean energy plants with CO{sub 2} capture. The AVESTAR Center was launched with a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with pre-combustion carbon capture. The IGCC dynamic simulator offers full-scope Operator Training Simulator (OTS) Human Machine Interface (HMI) graphics for realistic, real-time control room operation and is integrated with a 3D virtual Immersive Training Simulator (ITS), thus allowing joint control room and field operator training. The IGCC OTS/ITS solution combines a “gasification with CO{sub 2} capture” process simulator with a “combined cycle” power simulator into a single high-performance dynamic simulation framework. This presentation will describe progress on the development of a natural gas combined cycle (NGCC) dynamic simulator based on the syngas-fired combined cycle portion of AVESTAR’s IGCC dynamic simulator. The 574 MW gross NGCC power plant design consisting of two advanced F-class gas turbines, two heat recovery steam generators (HRSGs), and a steam turbine in a multi-shaft 2x2x1 configuration will be reviewed. Plans for integrating a post-combustion carbon capture system will also be discussed.

Liese, E.; Zitney, S.

2012-01-01T23:59:59.000Z

112

Evaluation and comparison of models and modelling tools simulating nitrogen processes in treatment wetlands  

Science Journals Connector (OSTI)

In this paper, two ecological models of nitrogen processes in treatment wetlands have been evaluated and compared. These models were implemented, simulated, and visualized using the Modelica modelling and simulation language [P. Fritzson, Principles of Object-Oriented Modelling and Simulation with Modelica 2.1 (Wiley-IEEE Press, USA, 2004).] and an associated tool. The differences and similarities between the MathModelica Model Editor and three other ecological modelling tools have also been evaluated. The results show that the models can well be modelled and simulated in the MathModelica Model Editor, and that nitrogen decrease in a constructed treatment wetland should be described and simulated using the Nitrification/Denitrification model as this model has the highest overall quality score and provides a more variable environment.

Stina Edelfeldt; Peter Fritzson

2008-01-01T23:59:59.000Z

113

Molecular simulation as a tool for studying lignin  

SciTech Connect (OSTI)

Lignocellulosic biomass provides a sustainable source of sugars for biofuel and biomaterial production. However, biomass resistance to degradation imposes difficulties for economical conversion of plant carbohydrates to fermentable sugars. One of the key contributors to recalcitrance is lignin. Understanding the properties of lignin macromolecules in the cell wall matrix is useful for manipulating biomass structure to generate more easily degradable biomass. Along with experimental techniques such as 2D-NMR and mass spectrometry, computational techniques can be useful for characterizing the structural and energetic properties of the biomass assembly and its individual constituents. Here, we provide a brief introduction to lignin, review some of the recent, relevant scientific literature, and give our perspectives on the role of molecular simulation in understanding lignin structure.

Sangha, Amandeep K [ORNL; Petridis, Loukas [ORNL; Smith, Jeremy C [ORNL; Ziebell, Angela L [ORNL; Parks, Jerry M [ORNL

2012-01-01T23:59:59.000Z

114

Avestar® - Syngas-Fired Combined Cycle Dynamic Simulator  

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

Syngas-Fired Combined Cycle Dynamic Simulator Syngas-Fired Combined Cycle Dynamic Simulator The AVESTAR® center offers courses using the Combined Cycle Simulator, focusing on the power generation process after gasification. This simulator is well-suited for concentrated training on operation and control of the gas and steam turbines; condensate, feed water, and circulating water systems; heat recovery steam generator; and selective catalytic reduction (SCR) unit. Combined cycle simulator startup operations include bringing up the gas turbine to rated speed on natural gas and then switching over to the firing of synthesis gas. Key capabilities of the Combined Cycle Simulator include: Combined Cycle Simulator Operator training station HMI display for overview of Gas Turbine - Train A Normal base load operation

115

Ad hoc continuum-atomistic thermostat for modeling heat flow in molecular dynamics simulations  

E-Print Network [OSTI]

Ad hoc continuum-atomistic thermostat for modeling heat flow in molecular dynamics simulations J 2004) An ad hoc thermostating procedure that couples a molecular dynamics (MD) simulation

Brenner, Donald W.

116

Use of High Dynamic Range Images for Improved Medical Simulations  

Science Journals Connector (OSTI)

Here we describe the use of high-dynamic range lighting techniques to improve the rendering quality of real-time medical simulation systems. Specifically we show our method of extracting the lighting information ...

Meagan Leflar; Omar Hesham; Chris Joslin

2009-01-01T23:59:59.000Z

117

Modelica® Library for Dynamic Simulation of Thermoelectric Generators  

Science Journals Connector (OSTI)

The contribution presents a new modeling library for the dynamic simulation of thermoelectric generators (TEG) in 1D spatial resolution. The core of the library is a model of the thermoelectric legs (TEL), which ...

M. Nesarajah; L. Exel; G. Frey

2014-01-01T23:59:59.000Z

118

Molecular Dynamics Simulation of Homogeneous Crystal Nucleation in Polyethylene  

E-Print Network [OSTI]

Using a realistic united-atom force field, molecular dynamics simulations were performed to study homogeneous nucleation of the crystal phase at about 30% supercooling from the melts of n-pentacontahectane (C150) and a ...

Yi, Peng

119

Molecular Dynamics Simulation Studies of Electrolytes andElectrolyte...  

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

Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C. es058smith2010p.pdf More Documents & Publications Molecular dynamics simulation and ab intio...

120

Dynameomics Database of Molecular Dynamics Simulations Project...  

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

in determining protein behavior and function. Accomplishments: Over 11,000 protein folding simulations are now available in the world's largest public database of protein...

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Modeling and optimization with Optimica and JModelica.org—Languages and tools for solving large-scale dynamic optimization problems  

Science Journals Connector (OSTI)

The Modelica language, targeted at modeling of complex physical systems, has gained increased attention during the last decade. Modelica is about to establish itself as a de facto standard in the modeling community with strong support both within academia and industry. While there are several tools, both commercial and free, supporting simulation of Modelica models few efforts have been made in the area of dynamic optimization of Modelica models. In this paper, an extension to the Modelica language, entitled Optimica, is reported. Optimica enables compact and intuitive formulations of optimization problems, static and dynamic, based on Modelica models. The paper also reports a novel Modelica-based open source project, JModelica.org, specifically targeted at dynamic optimization. JModelica.org supports the Optimica extension and offers an open platform based on established technologies, including Python, C, Java and XML. Examples are provided to demonstrate the capabilities of Optimica and JModelica.org.

J. Åkesson; K.-E. Årzén; M. Gäfvert; T. Bergdahl; H. Tummescheit

2010-01-01T23:59:59.000Z

122

NREL: Dynamic Maps, GIS Data, and Analysis Tools - Data Visualization &  

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

MapSearch Searching for maps has never been easier. A screen capture of the MapSearch Map view option Bookmark and Share Data Visualization & Geospatial Tools NREL's Geographic Information System (GIS) Team has developed tools that allow users to apply these data. These tools help determine things such as how much electricity can be produced from solar systems on a house or what renewable resources are available in a specific areas. Please visit http://maps.nrel.gov/ for the most current list of available NREL's GIS tools. If you have difficulty using these tools because of a disability, please contact the Webmaster. General Interactive Mapping Tools Access RE Atlas, Solar Power Prospector, PVWatts, and other popular tools that dynamically generate maps of renewable energy resources.

123

Detonation shock dynamics and comparisons with direct numerical simulation  

E-Print Network [OSTI]

Detonation shock dynamics and comparisons with direct numerical simulation Tariq D. Aslam # , and D­ nation and detonation shock dynamics (DSD) is made. The theory of DSD defines the motion of the detonation shock in terms of intrinsic geometry of the shock surface, in particular for condensed phase ex

Aslam, Tariq

124

Detonation shock dynamics and comparisons with direct numerical simulation  

E-Print Network [OSTI]

Detonation shock dynamics and comparisons with direct numerical simulation Tariq D. Aslam , and D- nation and detonation shock dynamics (DSD) is made. The theory of DSD defines the motion of the detonation shock in terms of intrinsic geometry of the shock surface, in particular for condensed phase ex

Aslam, Tariq

125

Patch dynamics: macroscopic simulation of multiscale systems , Y. Kevrekidis2  

E-Print Network [OSTI]

Patch dynamics: macroscopic simulation of multiscale systems G. Samaey1 , Y. Kevrekidis2 , D. Rose1-called "equation-free" framework, based on the idea of a so-called coarse-grained time-stepper. The patch dynamics microscopic model in small portions of the space-time domain (the patches). We present some theoretical

Gorban, Alexander N.

126

Parallel Transient Dynamics Simulations: Algorithms for Contact Detection  

E-Print Network [OSTI]

February 5, 1998 Abstract Transient dynamics simulations are commonly used to model phenomena such as car and deform with the objects as they undergo stress. Fluids (gasoline, water) or fluid­ like materials (soil is a natural candidate for the power of parallel computers. Unfortunately, these kinds of simulations have

Plimpton, Steve

127

Accelerated molecular dynamics and equation-free methods for simulating diffusion in solids.  

SciTech Connect (OSTI)

Many of the most important and hardest-to-solve problems related to the synthesis, performance, and aging of materials involve diffusion through the material or along surfaces and interfaces. These diffusion processes are driven by motions at the atomic scale, but traditional atomistic simulation methods such as molecular dynamics are limited to very short timescales on the order of the atomic vibration period (less than a picosecond), while macroscale diffusion takes place over timescales many orders of magnitude larger. We have completed an LDRD project with the goal of developing and implementing new simulation tools to overcome this timescale problem. In particular, we have focused on two main classes of methods: accelerated molecular dynamics methods that seek to extend the timescale attainable in atomistic simulations, and so-called 'equation-free' methods that combine a fine scale atomistic description of a system with a slower, coarse scale description in order to project the system forward over long times.

Deng, Jie; Zimmerman, Jonathan A.; Thompson, Aidan Patrick; Brown, William Michael (Oak Ridge National Laboratories, Oak Ridge, TN); Plimpton, Steven James; Zhou, Xiao Wang; Wagner, Gregory John; Erickson, Lindsay Crowl

2011-09-01T23:59:59.000Z

128

Rensselaer Component of the Terascale Simulation Tools and Technologies - Final Report  

SciTech Connect (OSTI)

The Terascale Simulation Tools and Technologies (TSTT) SciDAC center focused on the development and application on SciDAC applications of advanced technologies to support unstructured grid simulations. As part of the TSTT team the RPI group focused on developing automated adaptive mesh control tools and working with SciDAC accelerator and fusion applications on the use of these technologies to execute their simulations. The remainder of this report provides a brief summary of the efforts carried out by the RPI team to support SciDAC applications (Section 2) and to develop the TSTT technologies needed for those automated adaptive simulations (Section 3). More complete information on the technical developments can be found in the cited references and previous progress reports.

Mark S. Shephard

2009-08-03T23:59:59.000Z

129

Lattice Boltzmann versus Molecular Dynamics Simulation of Nanoscale Hydrodynamic Flows  

SciTech Connect (OSTI)

A fluid flow in a simple dense liquid, passing an obstacle in a two-dimensional thin film geometry, is simulated by molecular dynamics (MD) computer simulation and compared to results of lattice Boltzmann (LB) simulations. By the appropriate mapping of length and time units from LB to MD, the velocity field as obtained from MD is quantitatively reproduced by LB. The implications of this finding for prospective LB-MD multiscale applications are discussed.

Horbach, Juergen [Institut fuer Physik, Johannes-Gutenberg-Universitaet Mainz, Staudinger Weg 7, D-55099 Mainz (Germany); Succi, Sauro [Istituto Applicazioni Calcolo, CNR, Via le del Policlinico 137, 00161, Rome (Italy)

2006-06-09T23:59:59.000Z

130

Activity-based costing simulation as a tool for construction process optimization  

E-Print Network [OSTI]

Variable and fixed costs. . 111. 2. 3 Crash duration and cost. 111. 2. 4 Least cost scheduling 111. 2. 5 Optimization objectives. . . . . 15 17 17 18 19 20 23 CHAPTER IV APPLICATIONS OF OPTIMIZATION TOOLS IN CONSTRUCTION . . Page 25 IV. I... Excavation Project. . . . . . . . . . . . . . . . . . . . VIII. 2. 1 Option 1: with 15CY hauler . VIII. 2. 1. 1 STEP 1: Calculate resource balance point. . . . VIII. 2. 1. 2 STEP 2: Simulate the minimum ratios. . . . . . . . VIII. 2. 1. 3 STEP 3: Simulate...

Son, Junghye

1999-01-01T23:59:59.000Z

131

Molecular Dynamics Simulations of Protein Folding  

Science Journals Connector (OSTI)

I illustrate the use of the replica exchange molecular dynamics (REMD) algorithm to study the folding of a small (57 amino acids) protein that folds into a three-helix bundle, protein A. The REMD is a triviall...

Angel E. Garcia

2008-01-01T23:59:59.000Z

132

Building Design Advisor: Automated integration of multiple simulation tools K. Papamichael, J. LaPorta, H. Chauvet  

E-Print Network [OSTI]

LBNL-40591 Preprint Building Design Advisor: Automated integration of multiple simulation tools K Design Advisor (BDA) is a software environment that supports the integrated use of multiple analysis

133

GeneVis: visualization tools for genetic regulatory network dynamics  

Science Journals Connector (OSTI)

GeneVis provides a visual environment for exploring the dynamics of genetic regulatory networks. At present time, genetic regulation is the focus of intensive research worldwide, and computational aids are being called for to help in the research of ... Keywords: biological visualization, focus and context, genetic networks, lenses, multirepresentation, visualization

C. A. H Baker; M. S. T Carpendale; P. Prusinkiewicz; M. G. Surette

2002-10-01T23:59:59.000Z

134

ViGs: A Grid Simulation and Monitoring Tool for ATLAS Aaron T. Thor1  

E-Print Network [OSTI]

, as the performance of a grid computing architecture is closely tied with its networking infrastructure acrossViGs: A Grid Simulation and Monitoring Tool for ATLAS Workflows Aaron T. Thor1 , Gergely V. Záruba1 boundaries, and encouraging collaborations. To date, setting up large scale grids has been mostly

Záruba, Gergely

135

A complete FE simulation tools for NDT inspections with piezoelectric transducers  

E-Print Network [OSTI]

inspection system involves the generation, propagation and reception of short transient signals geometries. To accurately model the sensitivity in transmission and reception of such sensors, a transientA complete FE simulation tools for NDT inspections with piezoelectric transducers S. Imperialea

Boyer, Edmond

136

Generic tool for modelling and simulation of semiconductor intrabay material handling system  

Science Journals Connector (OSTI)

Semiconductor manufacturing facilities are migrating to 300 mm technology, necessitating the implementation of automated material handling systems (AMHS) for a variety of ergonomic and safety considerations. A predictive tool, such as software simulation, is needed at the planning stage to estimate the performance of these relatively new systems. Two forms of AMHS are in general use in industry one which handles material within a group of machines (a bay) and one which transfers material between bays. This paper presents a generic tool for modelling and simulation of an intrabay AMHS. The model utilises a library of different blocks representing the different components of any intrabay material handling system, providing a tool that allows rapid building and analysis of an AMHS under different operating conditions. The ease of use of the system means that inexpert users have the ability to generate good models.

K.S. El-Kilany; P. Young; M.A. El Baradie

2004-01-01T23:59:59.000Z

137

Conformational statistics of poly(dimethylsiloxane). 1. Probability distribution of rotational isomers from molecular dynamics simulations  

Science Journals Connector (OSTI)

Conformational statistics of poly(dimethylsiloxane). 1. Probability distribution of rotational isomers from molecular dynamics simulations ...

Ivet Bahar; Ignacio Zuniga; Robert Dodge; Wayne L. Mattice

1991-05-01T23:59:59.000Z

138

Development of Design and Simulation Tool for Hybrid Geothermal Heat Pump  

Open Energy Info (EERE)

Design and Simulation Tool for Hybrid Geothermal Heat Pump Design and Simulation Tool for Hybrid Geothermal Heat Pump System Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Development of Design and Simulation Tool for Hybrid Geothermal Heat Pump System Project Type / Topic 1 Recovery Act - Geothermal Technologies Program: Ground Source Heat Pumps Project Type / Topic 2 Topic Area 2: Data Gathering and Analysis Project Description eQUEST is a widely accepted building and HVAC system energy analysis tool (freeware) that is powered with the latest implementation of the DOE-2.2 program. Due to its user-friendly interface and comprehensive capacity for performing building load calculations and HVAC system simulations, eQUEST has been widely used in whole building performance analysis for various purposes, including LEED certification and optimization of building envelop and/or HVAC system designs. In 2006, as a cooperative effort between CM and JJH (the developer of eQUEST), eQUEST capabilities were expanded to include simulation of conventional GHP systems comprised of water-to-air heat pump units, horizontal or vertical ground loop heat exchangers (GLHE), and lakes or wells. However, to date, eQUEST does not model hybrid systems, such as the combination of a fluid cooler in series with a GLHE. Nor is it capable of simulating water-to-water heat pumps coupled to a horizontal or vertical GLHE. As a result, significant opportunities are being missed, as hybrid and/or water-to-water GHP system applications may prove to be a cost effective solution in many situations.

139

NREL: Dynamic Maps, GIS Data, and Analysis Tools - Webmaster  

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

Webmaster Webmaster To contact the Webmaster, please provide your name, e-mail address, and message below. When you are finished, click "Send Message." NOTE: If you enter your e-mail address incorrectly, we will be unable to reply. Your name: Your email address: Your message: Send Message Printable Version NREL GIS Home About NREL GIS Renewable Energy Technical Potential Maps Data Resources Data Visualization & Geospatial Tools GIS Staff Publications Mailing List Contact Us Did you find what you needed? Yes 1 No 0 Thank you for your feedback. Would you like to take a moment to tell us how we can improve this page? Submit We value your feedback. Thanks! We've received your feedback. Something went wrong. Please try again later. NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

140

NREL: Dynamic Maps, GIS Data, and Analysis Tools - Maps  

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

Bookmark and Share Bookmark and Share Maps NREL's GIS team develops maps for various renewable resources and for specific projects. As a benefit to the public, a majority of static maps are offered and Google Map (KML/KMZ) files on a tool called MapSearch. Biomass Maps Maps showing the biomass resources available in the United States by county. Feedstock categories include crop residues; forest residues; primary and secondary mill residues; urban wood waste; and methane emissions from manure management, landfills, and domestic wastewater treatment. Federal Energy Management Program The Federal Energy Management Program (FEMP) teamed with Geospatial Analysis staff at NREL to update the analysis for this project and created an interactive FEMP Screening Map application. The previous maps have been

Note: This page contains sample records for the topic "dynamic simulation tool" 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

NREL: Dynamic Maps, GIS Data, and Analysis Tools - Data Resources  

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

Bookmark and Share Bookmark and Share Data Resources NREL's Geographic Information System (GIS) team develops technology-specific GIS data maps for a variety of areas, as well as targeted analysis tools that can help determine availability of renewable energy resources. Geographic Information System Data NREL's GIS Team develops technology-specific GIS data maps for a variety of areas, including biomass, geothermal, solar, wind, and renewable hydrogen. The team has made some of our datasets available for download through this Web site. 10km and 40km solar datasets are available for the United States and some international sites. 50m wind datasets are available for specific states, regions and some international sites. 25km wind datasets are available for the United States. 90m offshore wind datasets are available

142

Coupled multi-body dynamics and CFD for wind turbine simulation including explicit wind turbulence  

Science Journals Connector (OSTI)

Abstract A high fidelity approach for wind turbine aero-elastic simulations including explicit representation of the atmospheric wind turbulence is presented. The approach uses a dynamic overset computational fluid dynamics (CFD) code for the aerodynamics coupled with a multi-body dynamics (MBD) code for the motion responses to the aerodynamic loads. Mann's wind turbulence model was implemented into the CFD code as boundary and initial conditions. The wind turbulence model was validated by comparing the theoretical one-point spectrum for the three components of the velocity fluctuations, and by comparing the expected statistics from the CFD simulated wind turbulent field with the explicit wind turbulence inlet boundary from Mann model. Extensive simulations based on the proposed coupled approach were conducted with the conceptual NREL 5-MW offshore wind turbine in an increasing level of complexity, analyzing the turbine behavior as elasticity, wind shear and atmospheric wind turbulence are added to the simulations. Results are compared with the publicly available simulations results from OC3 participants, showing good agreement for the aerodynamic loads and blade tip deflections in time and frequency domains. Wind turbulence/turbine interaction was examined for the wake flow. It was found that explicit turbulence addition results in considerably increased wake diffusion. The coupled CFD/MBD approach can be extended to include multibody models of the shaft, bearings, gearbox and generator, resulting in a promising tool for wind turbine design under complex operational environments.

Y. Li; A.M. Castro; T. Sinokrot; W. Prescott; P.M. Carrica

2015-01-01T23:59:59.000Z

143

Dynamic Ball & Socket Joint Force Simulator  

E-Print Network [OSTI]

................................................. 137 Appendix F Results ............................................................................................... 144 vi LIST OF FIGURES Figure 1. Autodesk rendering of the DBSJFS mounted inside the 858 Mini Bionix Machine... the perpendicular axes. Additionally, Figure 1 on the following page is an Autodesk rending of the DBSJFS that shows the orientation of the X’, Y’, and Z axes on the simulator. 15 Figure 1. Autodesk rendering of the DBSJFS mounted inside the 858 Mini Bionix...

Farmer, Ryan Neal

2011-07-26T23:59:59.000Z

144

An object-oriented approach to simulation of IRIS dynamic response  

Science Journals Connector (OSTI)

In this paper the development of an adequate modelling and simulation tool for Dynamics and Control tasks is presented. The key features of the developed simulator are: “Modularity” – the system model is built by connecting the models of its components, which are written independently of their boundary conditions; “Openness” – the code of each component model is clearly readable and close to the original equations and easily customised by the experienced user; “Efficiency” – the simulation code is fast; “Tool support” – the simulation tool is based on reliable, tested and well-documented software. To achieve these objectives, the Modelica language was used as a basis for the development of the simulator. The Modelica language is the result of recent advances in the field of object-oriented, multi-physics, dynamic system modelling. The language definition is open-source and it has already been successfully adopted in several industrial fields. The test bed for the application of the object-oriented approach has been the new generation, integral type, IRIS nuclear reactor. IRIS (International Reactor Innovative and Secure) is a pressurized light water cooled, small/medium power (335 MWe) reactor reactor, under development by an international consortium of nineteen organizations from ten countries. The preliminary design has been completed and the pre-application licensing process with the US-Nuclear Regulatory Commission (NRC) is underway. To provide the required capabilities for the analysis, specific models for the nuclear reactor components have been developed, to be applied for the dynamic simulation of the IRIS integral reactor, albeit keeping general validity for PWR plants. The following Modelica models have been written to satisfy the IRIS modelling requirements and are presented in this paper: point reactor kinetic, fuel heat transfer, control rods model, and a once-through type steam generator, thus obtaining a specific library of nuclear models and components. As far as other classical power generation plant components are concerned, the Thermo Power open library, developed at Politecnico di Milano as well, has been adopted and is briefly presented in the paper. Originally conceived for conventional, fossil-fired plants, the highly modular approach allowed to effectively reuse the models of the balance of plant systems, which have been connected to the models of the nuclear power generation process, to obtain a system simulator for the IRIS reactor. Finally, preliminary results of the code validation process and the reactor dynamics are presented.

Antonio Cammi; Francesco Casella; Marco E. Ricotti; Francesco Schiavo

2011-01-01T23:59:59.000Z

145

Metascalable quantum molecular dynamics simulations of hydrogen-on-demand  

Science Journals Connector (OSTI)

We enabled an unprecedented scale of quantum molecular dynamics simulations through algorithmic innovations. A new lean divide-and-conquer density functional theory algorithm significantly reduces the prefactor of the O(N) computational ... Keywords: density functional theory, divide-and-conquer, on-demand hydrogen production

Ken-ichi Nomura, Rajiv K. Kalia, Aiichiro Nakano, Priya Vashishta, Kohei Shimamura, Fuyuki Shimojo, Manaschai Kunaseth, Paul C. Messina, Nichols A. Romero

2014-11-01T23:59:59.000Z

146

Dynamic Simulation of DFIG Wind Turbines on FPGA Boards  

E-Print Network [OSTI]

Dynamic Simulation of DFIG Wind Turbines on FPGA Boards Hao Chen, Student Member, IEEE, Song Sun is a friction coefficient. The wind turbine model is based on the relation between the upstream wind speed V w + 1 where p is the air density; Rw is the wind turbine radius; cp (A, (3) is the performance

Zambreno, Joseph A.

147

Molecular dynamics simulations of boronnitride nanotubes embedded in  

E-Print Network [OSTI]

, theoretical studies suggest that BN nanotubes exhibit an energy gap of about 4--5 eV independent of chiralityMolecular dynamics simulations of boron­nitride nanotubes embedded in amorphous Si­B­N Michael In this article, we examine the elastic properties of boron­nitride nanotubes, which are embedded in amorphous

Ferrari, Patrik L.

148

Simulational nanoengineering: Molecular dynamics implementation of an atomistic Stirling engine  

E-Print Network [OSTI]

centuries ago and an early competitor of the steam engine, continues to attract interest owing to itsSimulational nanoengineering: Molecular dynamics implementation of an atomistic Stirling engine D 2009; published 30 April 2009 A nanoscale-sized Stirling engine with an atomistic working fluid has

Rapaport, Dennis C.

149

Interactive visual simulation of dynamic ink diffusion effects  

Science Journals Connector (OSTI)

This paper presents an effective method that simulates the ink diffusion process with visual plausible effects and real-time performance. Our algorithm updates the dynamic ink volume with a hybrid grid-particle representation: the fluid velocity field ... Keywords: industrial animation, ink diffusion, interaction, motion blur

Shibiao Xu; Xing Mei; Weiming Dong; Zhiyi Zhang; Xiaopeng Zhang

2011-12-01T23:59:59.000Z

150

A Molecular Dynamics Simulation of Hydrogen Storage with SWNTs  

E-Print Network [OSTI]

A Molecular Dynamics Simulation of Hydrogen Storage with SWNTs S. Maruyama and T. Kimura, Bunkyo-ku, Tokyo 113-8656, Japan The mechanism of efficient hydrogen storage (1) with SWNTs (2, and the storage amount became about 5 wt % regardless of the tube radius. The number of absorbed hydrogen

Maruyama, Shigeo

151

Hydrogen Raman shifts in carbon nanotubes from molecular dynamics simulation  

E-Print Network [OSTI]

Hydrogen Raman shifts in carbon nanotubes from molecular dynamics simulation S.J.V. Frankland *, D hydrogen in individual single-shell carbon nanotubes and nanotube ropes using a semiclassical model. The calculations predict that isolated hydrogen molecules inside of nanotubes have a Raman frequency that increases

Brenner, Donald W.

152

UNH Jerard/Fussell 1 Project Summary -Dynamic Evaluation of Machine Tool Process Capability  

E-Print Network [OSTI]

UNH ­ Jerard/Fussell 1 Project Summary - Dynamic Evaluation of Machine Tool Process Capability large and small plant operations and decisions. For example, we show some real world examples where part, annual expenditures on machining operations total more than $200 Billion or about 2% of GDP. · Self

New Hampshire, University of

153

ProChat: Dynamic Formal Collaboration Protocols in a Chat Tool for Handheld Collaboration  

E-Print Network [OSTI]

ProChat: Dynamic Formal Collaboration Protocols in a Chat Tool for Handheld Collaboration Randal K, or collaboration protocols, can be developed outside the application, analyzed for errors, shared among users protocols are used to modify the user interface to control the collaboration. We conclude with some open

North Carolina at Chapel Hill, University of

154

DOE/NETL IGCC Dynamic Simulator Research and Training Center  

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

NETL IGCC Dynamic Simulator NETL IGCC Dynamic Simulator Research and Training Center 01 Aug 2008 Volume 2: IGCC Process Descriptions DOE/NETL-2008/1324 NETL Collaboratory for Process & Dynamic Systems Research Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

155

Modeling and simulation of longitudinal dynamics for Low Energy Ring–High Energy Ring at the Positron-Electron Project  

Science Journals Connector (OSTI)

A time domain dynamic modeling and simulation tool for beam-cavity interactions in the Low Energy Ring (LER) and High Energy Ring (HER) at the Positron-Electron Project (PEP-II) is presented. Dynamic simulation results for PEP-II are compared to measurements of the actual machine. The motivation for this tool is to explore the stability margins and performance limits of PEP-II radio-frequency (RF) systems at future higher currents and upgraded RF configurations. It also serves as a test bed for new control algorithms and can define the ultimate limits of the low-level RF (LLRF) architecture. The time domain program captures the dynamic behavior of the beam-cavity-LLRF interaction based on a reduced model. The ring current is represented by macrobunches. Multiple RF stations in the ring are represented via one or two macrocavities. Each macrocavity captures the overall behavior of all the 2 or 4 cavity RF stations. Station models include nonlinear elements in the klystron and signal processing. This enables modeling the principal longitudinal impedance control loops interacting via the longitudinal beam model. The dynamics of the simulation model are validated by comparing the measured growth rates for the LER with simulation results. The simulated behavior of the LER at increased operation currents is presented via low-mode instability growth rates. Different control strategies are compared and the effects of both the imperfections in the LLRF signal processing and the nonlinear drivers and klystrons are explored.

C. Rivetta; T. Mastorides; J. D. Fox; D. Teytelman; D. Van Winkle

2007-02-21T23:59:59.000Z

156

Survey of Dynamic Simulation Programs for Nuclear Fuel Reprocessing  

SciTech Connect (OSTI)

The absence of any 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 industries. Modeling programs to simulate the dynamic behavior of nuclear fuel separations and processing were originally developed to support the US government’s mission of weapons production and defense fuel recovery. Consequently there has been little effort is the US devoted towards improving this specific process simulation capability during the last two or three decades. More recent work has been focused on elucidating chemical thermodynamics and developing better models of predicting equilibrium in actinide solvent extraction systems. These equilibrium models have been used to augment flowsheet development and testing primarily at laboratory scales. The development of more robust and complete process models has not kept pace with the vast improvements in computational power and user interface and is significantly behind simulation capability in other chemical processing and separation fields.

Troy J. Tranter; Daryl R. Haefner

2008-06-01T23:59:59.000Z

157

Library for modeling and simulating the thermal dynamics of buildings  

Science Journals Connector (OSTI)

Today's buildings consume more energy than any other sector of the U.S. economy, including transportation and industry; a similar importance can be expected in most European countries. Due to the increased interest in saving energy in buildings, new dynamic thermal models that describe transient response in more flexible modeling languages become necessary. Traditional building simulation software (e.g. TRNSYS or Energy Plus) are based on almost intractable simulation codes, difficult to maintain and modify, that predict system quantities at fixed time intervals. More clear code, properly separated from the simulation environment, with variable time step solvers would be necessary for the assessment of HVAC system performance with quicker dynamics. Following some ideas from a previous building thermal behavior library, a new enhanced Modelica library for modeling buildings is presented. The library basically consists of a combination of lumped parameter models and one-dimensional distributed parameter models that interconnects with each other through a set of common interfaces. Object-oriented features like class parameters and multiple-inheritance are used to improve the library structure making it easy to read and use. Complex building topologies can be built-up from component blocks that result in physically correct compound models that can be efficiently simulated and studied in any Modelica simulation environment.

Juan I. Videla; Bernt Lie

2006-01-01T23:59:59.000Z

158

Ancillary Services Analysis of an Offshore Wind Farm Cluster – Technical Integration Steps of a Simulation Tool  

Science Journals Connector (OSTI)

Abstract In this publication, the authors present methodology and example results for the analysis of ancillary services of an offshore wind farm cluster and its electrical power system. Thereby the operation tool Wind Cluster Management System (WCMS) is used as simulation tool to evaluate certain planning scenarios. Emphasis is made on two topics: 1) the integration of high voltage direct current (HVDC) technology to the WCMS, 2) the ancillary service analysis. As examples, voltage source converter based HVDC (VSC-HVDC) and the provision of reserve respectively balancing power are discussed in detail. The analyzed study case considers the Kriegers Flak area while the associated power system connects wind farms to Sweden, Denmark and Germany.

Tobias Hennig; Lothar Löwer; Luis Mariano Faiella; Sebastian Stock; Malte Jansen; Lutz Hofmann; Kurt Rohrig

2014-01-01T23:59:59.000Z

159

A Distributed Electrochemistry Modeling Tool for Simulating SOFC Performance and Degradation  

SciTech Connect (OSTI)

This report presents a distributed electrochemistry (DEC) model capable of investigating the electrochemistry and local conditions with the SOFC MEA based on the local microstructure and multi-physics. The DEC model can calculate the global current-voltage (I-V) performance of the cell as determined by the spatially varying local conditions through the thickness of the electrodes and electrolyte. The simulation tool is able to investigate the electrochemical performance based on characteristics of the electrode microstructure, such as particle size, pore size, electrolyte and electrode phase volume fractions, and triple-phase-boundary length. It can also investigate performance as affected by fuel and oxidant gas flow distributions and other environmental/experimental conditions such as temperature and fuel gas composition. The long-term objective for the DEC modeling tool is to investigate factors that cause electrode degradation and the decay of SOFC performance which decrease longevity.

Recknagle, Kurtis P.; Ryan, Emily M.; Khaleel, Mohammad A.

2011-10-13T23:59:59.000Z

160

Simulating Soil Carbon Dynamics, Erosion and Tillage with EPIC  

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

Simulating Soil Carbon Dynamics, Erosion Simulating Soil Carbon Dynamics, Erosion and Tillage with EPIC 1 R. C. Izaurralde (cesar.izaurralde@pnl.gov; 202-646-5227) Joint Global Change Research Institute (JGCRI) Pacific Northwest Nat'l Lab. - Univ. of Maryland 901 D St. S.W., Suite 900 Washington, DC 20024-2115 J. R. Williams (williams@brc.tamus.edu; 254-774-6124) Texas A&M University Blackland Research Center 808 East Blackland Road Temple, TX 76502 W. B. McGill (mcgill@unbc.ca) Faculty of Science and Management University of Northern British Columbia 3333 University Way, Prince George, BC V2N 4Z9 N. J. Rosenberg (nj.rosenberg@pnl.gov; 202-646-5029) Joint Global Change Research Institute (JGCRI) Pacific Northwest Nat'l Lab. - Univ. of Maryland 901 D St. S.W., Suite 900 Washington, DC 20024-2115

Note: This page contains sample records for the topic "dynamic simulation tool" 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

AVESTAR® - Oxy-Coal Carbon Capture (OCCC) Dynamic Simulator  

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

Oxy-Coal Carbon Capture (OCCC) Dynamic Simulator Oxy-Coal Carbon Capture (OCCC) Dynamic Simulator FutureGen 2.0 is a first-of-its-kind, near-zero emissions coal-fueled power plant using oxy-combustion technology to capture the plant's carbon emissions. To help meet the Nation's ever growing demand for clean energy, the FutureGen Industrial Alliance (Alliance) was formed to test and commercialize advanced coal-based systems fully integrated with carbon capture and geologic storage technologies. In cooperation with the U.S. Department of Energy (DOE), the Alliance and its project partners AirLiquide and Babcock & Wilcox, will upgrade an existing power plant in Meredosia, Illinois with oxy-coal carbon capture (OCCC) technology to capture and permanantly store approximately 1.0 million tonnes of CO2 each year.

162

Cellular-automaton-based simulation of 2D polymer dynamics  

Science Journals Connector (OSTI)

A cellular-automaton-based model that simulates flexible polymers in good solvents is constructed. Excluded-volume effects as well as hydrodynamic interactions are incorporated in this model in a very natural way. The center-of-mass velocity autocorrelation function of a single polymer chain in a 2D solution is found to obey a dynamic scaling relation which violates the nondraining concept.

J. M. Vianney A. Koelman

1990-04-16T23:59:59.000Z

163

Simulational nanoengineering: Molecular dynamics implementation of an atomistic Stirling engine  

Science Journals Connector (OSTI)

A nanoscale-sized Stirling engine with an atomistic working fluid has been modeled using molecular dynamics simulation. The design includes heat exchangers based on thermostats, pistons attached to a flywheel under load, and a regenerator. Key aspects of the behavior, including the time-dependent flows, are described. The model is shown to be capable of stable operation while producing net work at a moderate level of efficiency.

D. C. Rapaport

2009-04-30T23:59:59.000Z

164

Short-Range Order and Collective Dynamics of DMPC Bilayers: A Comparison between Molecular Dynamics Simulations, X-Ray,  

E-Print Network [OSTI]

Simulations, X-Ray, and Neutron Scattering Experiments Jochen S. Hub,* Tim Salditt,y Maikel C. Rheinsta derived by molecular dynamics simulations, elastic x-ray, and inelastic neutron scattering experiments dynamics obtained from the simulations and from inelastic neutron scattering are analyzed and compared

de Groot, Bert

165

Molecular dynamics simulations of the nano-scale room-temperature oxidation of aluminum single crystals  

E-Print Network [OSTI]

Molecular dynamics simulations of the nano-scale room-temperature oxidation of aluminum single Abstract The oxidation of aluminum single crystals is studied using molecular dynamics (MD) simulations with dynamic charge transfer between atoms. The simulations are performed on three aluminum low-index surfaces

Southern California, University of

166

MODELING PLANT COMPETITION WITH THE GAPS OBJECT-ORIENTED DYNAMIC SIMULATION MODEL  

E-Print Network [OSTI]

MODELING PLANT COMPETITION WITH THE GAPS OBJECT-ORIENTED DYNAMIC SIMULATION MODEL David G. Rossiter of Agronomy, Inc. #12;MODELING PLANT COMPETITION WITH THE GAPS OBJECT-ORIENTED DYNAMIC SIMULATION MODEL Abstract Modeling inter-species competition is a natural application for dynamic simulation models

Rossiter, D G "David"

167

Development of a Simplified Simulation Tool for High Performance K-5 Schools in Hot and Humid Climates  

E-Print Network [OSTI]

hourly building energy usage: The great energy predictor shootout-overview and discussion of results. ASHRAE Transactions 100(2):1104-1118. Perkins, B. 2001. Building type basics for elementary and secondary schools, John Wiley & Sons, INC. New York... new school building. OBJECTIVES The purpose of this study is to develop a simplified simulation tool for K-5 high performance schools in hot and humid climates. The tool will be developed using the DOE-2.1e building energy simulation program...

Im, P.; Haberl, J. S.

168

Demonstration of a Computational Fluid Dynamics (CFD) Tool Used for Data  

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

Demonstration of a Computational Fluid Dynamics (CFD) Tool Used for Data Demonstration of a Computational Fluid Dynamics (CFD) Tool Used for Data Center Modeling, Thermal Analysis and Operational Management Speaker(s): Saket Karajgikar Date: November 11, 2010 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Henry Coles Every Data Center built today is designed with a total capacity in mind, as well as a plan to grow into this final-day load. On a daily basis, Data Center Operations/Management professionals work toward keeping their Data Center as close to this plan as possible by concurrently managing the available power, space, cooling and airflow resources. Unfortunately, lack of communication and information, the pace of change and difficulty in coping with the ever growing power densities of IT equipment can prevent a

169

Dynamic modeling of steam power cycles: Part II – Simulation of a small simple Rankine cycle system  

Science Journals Connector (OSTI)

This paper presents the second part of the work concerning the dynamic simulation of small steam cycle plants for power generation. The work is part of the preliminary study for a 600 kWe biomass fired steam power plant for which the complete open-loop, lumped parameter dynamic model of the steam cycle has been developed using the SimECS software described in Part I of this work. For these low-power plants, a dynamic simulation tool is especially useful because these systems must be designed to operate in transient mode for most of the time. The plant model presented here consists of the following components: feedwater pump, economizer, evaporator, superheater, impulse turbine, electrical generator and condenser. The primary heat source is modeled as a flue gas flow and no combustion models are incorporated yet to model the furnace. A description of the various components forming the complete steam cycle is given to illustrate the capabilities and modularity of the developed modeling technique. The model is first validated quantitatively against steady-state values obtained using a well known, reliable steady-state process modeling software. Subsequently, the dynamic validation is presented. Results can only be discussed based on the qualitative assessment of the observed trends because measurements are not available, being the plant in the preliminary design phase. The qualitative validation is based on four dynamic simulations involving three small step disturbances of different magnitude imposed on the pump rotational speed and on the flue gas mass flow and a single large ramp disturbance on the flue gas mass flow.

H. van Putten; P. Colonna

2007-01-01T23:59:59.000Z

170

E-Print Network 3.0 - alliances simulation platform Sample Search...  

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

and analysis tool capable of analyzing floating platform concepts for offshore wind turbines. The new modeling... dynamic simulation tool will enable the development of...

171

Molecular Dynamics Simulations from SNL's Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS)  

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

LAMMPS (http://lammps.sandia.gov/index.html) stands for Large-scale Atomic/Molecular Massively Parallel Simulator and is a code that can be used to model atoms or, as the LAMMPS website says, as a parallel particle simulator at the atomic, meso, or continuum scale. This Sandia-based website provides a long list of animations from large simulations. These were created using different visualization packages to read LAMMPS output, and each one provides the name of the PI and a brief description of the work done or visualization package used. See also the static images produced from simulations at http://lammps.sandia.gov/pictures.html The foundation paper for LAMMPS is: S. Plimpton, Fast Parallel Algorithms for Short-Range Molecular Dynamics, J Comp Phys, 117, 1-19 (1995), but the website also lists other papers describing contributions to LAMMPS over the years.

Plimpton, Steve; Thompson, Aidan; Crozier, Paul

172

The OpenSTORM Project: A Proposal for an Open Simulation Tool for Robotics, Automation, and Manufacturing  

E-Print Network [OSTI]

The OpenSTORM Project: A Proposal for an Open Simulation Tool for Robotics, Automation Models for Locomotion and Manipulation, and the upcoming IEEE Conference on Automation Sci- ence by improving our rapid-prototyping and system verification capabilities. Our view is that a single simulation

O'Brien, James F.

173

Reservoir Modeling by Data Integration via Intermediate Spaces and Artificial Intelligence Tools in MPS Simulation Frameworks  

SciTech Connect (OSTI)

Conditioning stochastic simulations are very important in many geostatistical applications that call for the introduction of nonlinear and multiple-point data in reservoir modeling. Here, a new methodology is proposed for the incorporation of different data types into multiple-point statistics (MPS) simulation frameworks. Unlike the previous techniques that call for an approximate forward model (filter) for integration of secondary data into geologically constructed models, the proposed approach develops an intermediate space where all the primary and secondary data are easily mapped onto. Definition of the intermediate space, as may be achieved via application of artificial intelligence tools like neural networks and fuzzy inference systems, eliminates the need for using filters as in previous techniques. The applicability of the proposed approach in conditioning MPS simulations to static and geologic data is verified by modeling a real example of discrete fracture networks using conventional well-log data. The training patterns are well reproduced in the realizations, while the model is also consistent with the map of secondary data.

Ahmadi, Rouhollah, E-mail: rouhollahahmadi@yahoo.com [Amirkabir University of Technology, PhD Student at Reservoir Engineering, Department of Petroleum Engineering (Iran, Islamic Republic of)] [Amirkabir University of Technology, PhD Student at Reservoir Engineering, Department of Petroleum Engineering (Iran, Islamic Republic of); Khamehchi, Ehsan [Amirkabir University of Technology, Faculty of Petroleum Engineering (Iran, Islamic Republic of)] [Amirkabir University of Technology, Faculty of Petroleum Engineering (Iran, Islamic Republic of)

2013-12-15T23:59:59.000Z

174

Learning environment simulator: a tool for local decision makers and first responders  

SciTech Connect (OSTI)

The National Infrastructure Simulation and Analysis Center (NISAC) has developed a prototype learning environment simulator (LES) based on the Critical Infrastructure Protection Decision Support System (CIPDSS) infrastructure and scenario models. The LES is designed to engage decision makers at the grass-roots level (local/city/state) to deepen their understanding of an evolving crisis, enhance their intuition and allow them to test their own strategies for events before they occur. An initial version is being developed, centered on a pandemic influenza outbreak and has been successfully tested with a group of hospital administrators and first responders. LES is not a predictive tool but rather a simulated environment allowing the user to experience the complexities of a crisis before it happens. Users can contrast various approaches to the crisis, competing with alternative strategies of their own or other participants. LES is designed to assist decision makers in making informed choices by functionally representing relevant scenarios before they occur, including impacts to critical infrastructures with their interdependencies, and estimating human health & safety and economic impacts. In this paper a brief overview of the underlying models are given followed by a description of the LES, its interface and usage and an overview of the experience testing LES with a group of hospital administrators and first responders. The paper concludes with a brief discussion of the work remaining to make LES operational.

Leclaire, Rene J [Los Alamos National Laboratory; Hirsch, Gary B [CLE, INCORPORATED

2009-01-01T23:59:59.000Z

175

With faster processors and better numerical techniques, computational fluid dynamics (CFD) tools have revolutionized engineering design and optimization--  

E-Print Network [OSTI]

With faster processors and better numerical techniques, computational fluid dynamics (CFD) tools have revolutionized engineering design and optimization-- limiting expensive experimentation and Engineering Division (GED) at Southwest Research Institute® (SwRI®) has extensive experience and capabilities

Chapman, Clark R.

176

Molecular dynamics simulation of hydrogen diffusion in titanium  

National Nuclear Security Administration (NNSA)

9: Computation Physics 9: Computation Physics Atomistic Simulation of Hydrogen Diffusion in Titanium. Alexandr S. Rokhmanenkov, Alexey Yu. Kuksin, and Vladimir V. Stegailov All-Russia Research Institute of Automatics, Moscow 125412, Russia rohmanenkov@gmail.com Summary Study of the behavior of hydrogen in metals and alloys. The study is based on classical molecular dynamics (MD) and density functional theory (DFT) calculations. Study of the behavior of hydrogen in metals and alloys is of great importance due to the practical uses of hydrogen-metal systems for absorption of nuclear radiation, in neutron sources, for storage of hydrogen, or as catalyzers. This work is devoted to atomistic simulation of hydrogen diffusion in titanium hydrides and the effect of stresses and lattice defects on diffusivity.

177

Molecular Dynamics Simulations of Solutions at Constant Chemical Potential  

E-Print Network [OSTI]

Molecular Dynamics studies of chemical processes in solution are of great value in a wide spectrum of applications, that range from nano-technology to pharmaceutical chemistry. However, these calculations are affected by severe finite-size effects, such as the solution being depleted as the chemical process proceeds, that influence the outcome of the simulations. To overcome these limitations, one must allow the system to exchange molecules with a macroscopic reservoir, thus sampling a Grand-Canonical ensemble. Despite the fact that different remedies have been proposed, this still represents a key challenge in molecular simulations. In the present work we propose the C$\\mu$MD method, which introduces an external force that controls the environment of the chemical process of interest. This external force, drawing molecules from a finite reservoir, maintains the chemical potential constant in the region where the process takes place. We have applied the C$\\mu$MD method to the paradigmatic case of urea crystall...

Perego, Claudio; Parrinello, Michele

2015-01-01T23:59:59.000Z

178

Molecular dynamics simulations of optical conductivity of dense plasmas  

Science Journals Connector (OSTI)

The optical conductivity ?(?) for dense Coulomb systems is investigated using molecular dynamics simulations on the basis of pseudopotentials to mimic quantum effects. Starting from linear response theory, the response in the long-wavelength limit k=0 can be expressed by different types of autocorrelation functions (ACF’s) such as the current ACF, the force ACF, or the charge density ACF. Consistent simulation data for transverse as well as longitudinal ACF’s are shown which are based on calculations with high numerical accuracy. Results are compared with perturbation expansions which are restricted to small values of the plasma parameter. The relevance with respect to a quantum Coulomb plasma is discussed. Finally, results are presented showing a consistent description of these model plasmas in comparison to quantum statistical approaches and to experimental data.

I. Morozov, H. Reinholz, G. Röpke, A. Wierling, and G. Zwicknagel

2005-06-22T23:59:59.000Z

179

HyPro: A Financial Tool for Simulating Hydrogen Infrastructure Development, Final Report  

SciTech Connect (OSTI)

This report summarizes a multi-year Directed Technologies Inc. (DTI) project to study the build-out of hydrogen production facilities during the transition from gasoline internal combustion engine vehicle to hydrogen fuel cell vehicles. The primary objectives of the project are to develop an enhanced understanding of hydrogen production issues during the transition period (out to 2050) and to develop recommendations for the DOE on areas of further study. These objectives are achieved by conducting economic and scenario analysis to predict how industry would provide the hydrogen production, delivery and dispensing capabilities necessary to satisfy increased hydrogen demand. The primary tool used for the analysis is a custom created MatLab simulation tool entitled HyPro (short for Hydrogen Production). This report describes the calculation methodology used in HyPro, the baseline assumptions, the results of the baseline analysis and several corollary studies. The appendices of this report included a complete listing of model assumptions (capital costs, efficiencies, feedstock prices, delivery distances, etc.) and a step-by-step manual on the specific operation of the HyPro program. This study was made possible with funding from the U.S. Department of Energy (DOE).

Brian D. James, Peter O. Schmidt, Julie Perez

2008-12-01T23:59:59.000Z

180

Molecular Dynamics Simulation of Hydrogen Storage with Single Walled Carbon Nanotubes Shigeo MARUYAMA1,2  

E-Print Network [OSTI]

Molecular Dynamics Simulation of Hydrogen Storage with Single Walled Carbon Nanotubes * Shigeo-8656 The hydrogen storage mechanism of SWNTs was studied through molecular dynamics simulations. Assuming the simple : Molecular Dynamics Method, Hydrogen Storage, Single Walled Carbon Nanotubes, Lennard-Jones, Adsorption

Maruyama, Shigeo

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Modeling dilute sediment suspension using large-eddy simulation with a dynamic mixed model  

E-Print Network [OSTI]

Modeling dilute sediment suspension using large-eddy simulation with a dynamic mixed model Yi Transport of suspended sediment in high Reynolds number channel flows Re=O 600 000 is simulated using large-eddy simulation along with a dynamic-mixed model DMM . Because the modeled sediment concentration is low

Fringer, Oliver B.

182

Static and Dynamic Simulation of Steam Methane Reformers  

Science Journals Connector (OSTI)

The steam-methane reaction is an essential step for many processing plants. Hydrogen, ammonia and methanol are mostly produced by means of methane steam reforming. Since hydrogen is essential for any refinery employing hydrotreating, the performance monitoring of the hydrogen plant is highly desirable. The use of models or simulation is now a standard practice in most chemical plants and refineries. However, reliable models are still lacking for speciality reactors like the methane steam reformer. This paper describes steady-state and dynamic models for the reactions involved in reforming methane and higher hydrocarbon gases. The performance of the reformer is then illustrated by sensitivity analysis to various input disturbances like inlet pressure, temperature, feed concentration and rate, fuel rate and density and steam to carbon ratio. The effect of these disturbances on exit temperature and conversion is studied and analyzed. Catalyst deactivation effects are also discussed and it is shown by sample calculations that the simulator can give insight into catalyst performance and assist in monitoring catalyst deactivation. The transient effects are also reported and dynamic elements like gains and response time are discussed. Such information should give insight into controller design and effects of various parameters.

I.M. Alatiqi; A.M. Meziou; G.A. Gasmelseed

1989-01-01T23:59:59.000Z

183

Physics and Algorithm Enhancements for a Validated MCNP/X Monte Carlo Simulation Tool, Phase VII  

SciTech Connect (OSTI)

Currently the US lacks an end-to-end (i.e., source-to-detector) radiation transport simulation code with predictive capability for the broad range of DHS nuclear material detection applications. For example, gaps in the physics, along with inadequate analysis algorithms, make it difficult for Monte Carlo simulations to provide a comprehensive evaluation, design, and optimization of proposed interrogation systems. With the development and implementation of several key physics and algorithm enhancements, along with needed improvements in evaluated data and benchmark measurements, the MCNP/X Monte Carlo codes will provide designers, operators, and systems analysts with a validated tool for developing state-of-the-art active and passive detection systems. This project is currently in its seventh year (Phase VII). This presentation will review thirty enhancements that have been implemented in MCNPX over the last 3 years and were included in the 2011 release of version 2.7.0. These improvements include 12 physics enhancements, 4 source enhancements, 8 tally enhancements, and 6 other enhancements. Examples and results will be provided for each of these features. The presentation will also discuss the eight enhancements that will be migrated into MCNP6 over the upcoming year.

McKinney, Gregg W [Los Alamos National Laboratory

2012-07-17T23:59:59.000Z

184

Linear interfacial polymerization: Theory and simulations with dissipative particle dynamics  

Science Journals Connector (OSTI)

Step-growth alternating interfacial polymerization between two miscible or immiscible monomer melts is investigated theoretically and by dissipative particle dynamics simulations. In both cases the kinetics for an initially bilayer system passes from the reaction to diffusion control. The polymer composed of immiscible monomers precipitates at the interface forming a film of nearly uniform density. It is demonstrated that the reaction proceeds in a narrow zone which expands much slower than the whole film so that newly formed polymer is extruded from the reaction zone. This concept of “reactive extrusion” is used to analytically predict the degree of polymerization and distribution of all components (monomers polymer and end groups) within the film in close agreement with the simulations. Increasing the comonomer incompatibility leads to thinner and more uniform films with the higher average degree of polymerization. The final product is considerably more polydisperse than expected for the homogeneous step-growth polymerization. The results extend the previous theoretical reports on interfacial polymerization and provide new insights into the internal film structure and polymer characteristics which are important for membrane preparation microencapsulation and 3D printing technologies. A systematic way of mapping the simulation data onto laboratory scales is discussed.

2014-01-01T23:59:59.000Z

185

MOLECULAR DYNAMICS SIMULATIONS OF DISPLACEMENT CASCADES IN MOLYBDENUM  

SciTech Connect (OSTI)

Molecular dynamics calculations have been employed to simulate displacement cascades in neutron irradiated Mo. A total of 90 simulations were conducted for PKA energies between 1 and 40 keV and temperatures from 298 to 923K. The results suggest very little effect of temperature on final defect count and configuration, but do display a temperature effect on peak defect generation prior to cascade collapse. Cascade efficiency, relative to the NRT model, is computed to lie between 1/4 and 1/3 in agreement with simulations performed on previous systems. There is a tendency for both interstitials and vacancies to cluster together following cascade collapse producing vacancy rich regions surrounded by interstitials. Although coming to rest in close proximity, the point defects comprising the clusters generally do not lie within the nearest neighbor positions of one another, except for the formation of dumbbell di-interstitials. Cascades produced at higher PKA energies (20 or 40 keV) exhibit the formation of subcascades.

Smith, Richard Whiting

2003-09-08T23:59:59.000Z

186

Decision support for integrated refinery supply chains: Part 1. Dynamic simulation  

Science Journals Connector (OSTI)

Supply chain studies are increasingly given top priority in enterprise-wide management. Present-day supply chains involve numerous, heterogeneous, geographically distributed entities with varying dynamics, uncertainties, and complexity. The performance of a supply chain relies on the quality of a multitude of design and operational decisions made by the various entities. In this two-part paper, we demonstrate that a dynamic model of an integrated supply chain can serve as a valuable quantitative tool that aids in such decision-making. In this Part 1, we present a dynamic model of an integrated refinery supply chain. The model explicitly considers the various supply chain activities such as crude oil supply and transportation, along with intra-refinery supply chain activities such as procurement planning, scheduling, and operations management. Discrete supply chain activities are integrated along with continuous production through bridging procurement, production, and demand management activities. Stochastic variations in transportation, yields, prices, and operational problems are considered in the proposed model. The economics of the refinery supply chain includes consideration of different crude slates, product prices, operation costs, transportation, etc. The proposed model has been implemented as a dynamic simulator, called Integrated Refinery In-Silico (IRIS). IRIS allows the user the flexibility to modify not only parameters, but also replace different policies and decision-making algorithms in a plug-and-play manner. It thus allows the user to simulate and analyze different policies, configurations, uncertainties, etc., through an easy-to-use graphical interface. The capabilities of IRIS for strategic and tactical decision support are illustrated using several case studies.

Suresh S. Pitty; Wenkai Li; Arief Adhitya; Rajagopalan Srinivasan; I.A. Karimi

2008-01-01T23:59:59.000Z

187

Evaluation of servo, geometric and dynamic error sources on five axis high-speed machine tool  

E-Print Network [OSTI]

Many sources of errors exist in the manufacturing process of complex shapes. Some approximations occur at each step from the design geometry to the machined part. The aim of the paper is to present a method to evaluate the effect of high speed and high dynamic load on volumetric errors at the tool center point. The interpolator output signals and the machine encoder signals are recorded and compared to evaluate the contouring errors resulting from each axis follow-up error. The machine encoder signals are also compared to the actual tool center point position as recorded with a non-contact measuring instrument called CapBall to evaluate the total geometric errors. The novelty of the work lies in the method that is proposed to decompose the geometric errors in two categories: the quasi-static geometric errors independent from the speed of the trajectory and the dynamic geometric errors, dependent on the programmed feed rate and resulting from the machine structure deflection during the acceleration of its axes...

Andolfatto, Loïc; Mayer, René

2011-01-01T23:59:59.000Z

188

Effects of confinement on water structure and dynamics and on proton transport: a molecular simulation study  

E-Print Network [OSTI]

Classical molecular dynamics (MD) simulations are performed to study structural and dynamic properties of water confined within graphite surfaces. The surfaces are separated at distances varying between 7 and 14.5 Å and the water density is held...

Hirunsit, Pussana

2009-05-15T23:59:59.000Z

189

Computational fluid dynamics (CFD) simulations of aerosol in a u-shaped steam generator tube  

E-Print Network [OSTI]

as the physical model replicated for numerical simulation. Realizable k-? and standard k-? turbulence models were selected from the computational fluid dynamics (CFD) code, FLUENT, to provide the Eulerian description of the gaseous phase. Flow field simulation...

Longmire, Pamela

2009-05-15T23:59:59.000Z

190

INVESTIGATION OF SYSTEM DYNAMICS APPLIED TO BUILDING SIMULATION FOR ANTI-TERRORISM RESOURCE ALLOCATION  

E-Print Network [OSTI]

INVESTIGATION OF SYSTEM DYNAMICS APPLIED TO BUILDING SIMULATION FOR ANTI-TERRORISM RESOURCE ............................................................................. 26 2.8 Terrorism-Resistant Design

Bank, Lawrence C.

191

Development of an object-oriented dynamics simulator for a LFR DEMO  

SciTech Connect (OSTI)

A control-oriented dynamics simulator for a Generation IV Lead-cooled Fast Reactor (LFR) demonstrator (DEMO) has been developed aimed at providing a flexible, simple and fast-running tool allowing to perform design-basis transient and stability analyses, and to lay the foundations for the study of the system control strategy. For such purposes, a model representing a compromise between accuracy and straightforwardness has been necessarily sought, and in this view an object-oriented approach based on the Modelica language has been adopted. The reactor primary and secondary systems have been implemented by assembling both component models already available in a specific thermal-hydraulic library, and ad hoc developed nuclear component models suitably modified according to the specific DEMO configuration. The resulting overall plant simulator, incorporating also the balance of plant, consists in the following essential parts: core, integrated steam generator/primary pump block, cold and hot legs, primary coolant cold pool, turbine, heat sink, secondary coolant pump. Afterwards, the reactor response to typical transient initiators has been investigated: feedwater mass flow rate and temperature enhancement, turbine admission valve coefficient variation, increase of primary coolant mass flow rate, and transient of overpower have been simulated; results have been compared with the outcomes of analogous analyses performed by employing a lumped-parameter DEMO plant model. (authors)

Ponciroli, R.; Bortot, S.; Lorenzi, S.; Cammi, A. [Politecnico di Milano, Dept. of Energy, CeSNEF-Nuclear Engineering Div., via Ponzio 34/3, 20133 Milano (Italy)

2012-07-01T23:59:59.000Z

192

Pseudorandom number generator for massively parallel molecular-dynamics simulations  

Science Journals Connector (OSTI)

A class of uniform pseudorandom number generators is proposed for modeling and simulations on massively parallel computers. The algorithm is simple, nonrecursive, and is easily transported to serial or vector computers. We have tested the procedure for uniformity, independence, and correlations by several methods. Related, less complex sequences passed some of these tests well enough; however, inadequacies were revealed by tests for correlations and in an interesting application, namely, annealing from an initial lattice that is mechanically unstable. In the latter case, initial velocities chosen by a random number generator that is not sufficiently random lead quickly to unphysical regularity in grain structure. The new class of generators passes this dynamical diagnostic for unwanted correlations.

Brad Lee Holian; Ora E. Percus; Tony T. Warnock; Paula A. Whitlock

1994-08-01T23:59:59.000Z

193

Localized dynamic subgrid closure for simulation of magnetohydrodynamic turbulence  

SciTech Connect (OSTI)

A local dynamic kinetic energy model (LDKM) for large-eddy simulation (LES) of magnetohydrodynamic (MHD) turbulence is proposed. The proposed MHD turbulence model evaluates all model coefficients locally and dynamically without any ad hoc averaging. This model also does not assume low magnetic Reynolds numbers. The turbulent residual-helicity effect ({alpha}-effect) appearing in the magnetic induction equation is successfully modeled. For validation, high-Re decaying isotropic decay turbulence with and without a mean magnetic field are studied using LES. The effect of rotation is also studied. For the case without rotation, it is observed that the energy spectrum follows a k{sup -5/3} law. For the case with rotation, it is shown that two mechanisms, phase scrambling due to frame rotation and Joule dissipation, are competing, and two distinct regimes with respect to rotation rate are observed. There is a critical rotation rate at which the energy decays most in MHD turbulence. It is also shown that this MHD-LDKM model is applicable to wide variety of high/low magnetic Reynolds number applications.

Miki, Kenji; Menon, Suresh [Georgia Institute of Technology, School of Aerospace Engineering, Atlanta, Georgia 30332-0150 (United States)

2008-07-15T23:59:59.000Z

194

Calibrated Langevin-dynamics simulations of intrinsically disordered proteins  

Science Journals Connector (OSTI)

We perform extensive coarse-grained (CG) Langevin dynamics simulations of intrinsically disordered proteins (IDPs), which possess fluctuating conformational statistics between that for excluded volume random walks and collapsed globules. Our CG model includes repulsive steric, attractive hydrophobic, and electrostatic interactions between residues and is calibrated to a large collection of single-molecule fluorescence resonance energy transfer data on the interresidue separations for 36 pairs of residues in five IDPs: ??, ??, and ?-synuclein, the microtubule-associated protein ?, and prothymosin ?. We find that our CG model is able to recapitulate the average interresidue separations regardless of the choice of the hydrophobicity scale, which shows that our calibrated model can robustly capture the conformational dynamics of IDPs. We then employ our model to study the scaling of the radius of gyration with chemical distance in 11 known IDPs. We identify a strong correlation between the distance to the dividing line between folded proteins and IDPs in the mean charge and hydrophobicity space and the scaling exponent of the radius of gyration with chemical distance along the protein.

W. Wendell Smith; Po-Yi Ho; Corey S. O'Hern

2014-10-13T23:59:59.000Z

195

The Liberty Simulation Environment as a Pedagogical Tool Jason Blome Manish Vachharajani Neil Vachharajani David I. August  

E-Print Network [OSTI]

The Liberty Simulation Environment as a Pedagogical Tool Jason Blome Manish Vachharajani Neil {blome, manishv, nvachhar, august}@cs.princeton.edu Abstract This paper describes how the Liberty-length project. While a project of this type is better than no design experience, it only provides insights about

Lee, Jae W.

196

Modeling Miscanthus in the Soil and Water Assessment Tool (SWAT) to Simulate Its Water Quality Effects As a Bioenergy Crop  

Science Journals Connector (OSTI)

Modeling Miscanthus in the Soil and Water Assessment Tool (SWAT) to Simulate Its Water Quality Effects As a Bioenergy Crop ... There is increasing interest in perennial grasses as a renewable source of bioenergy and feedstock for second-generation cellulosic biofuels. ... Due to global warming and energy independence concerns, there is increasing interest in perennial grasses as a renewable source of bioenergy. ...

Tze Ling Ng; J. Wayland Eheart; Ximing Cai; Fernando Miguez

2010-08-03T23:59:59.000Z

197

CHEOPS: A tool-integration platform for chemical process modelling and simulation  

Science Journals Connector (OSTI)

A large number of modelling tools exist for the construction and solution of mathematical models of chemical processes. Each (chemical) process modelling tool provides its own model ... This paper presents a conc...

G. Schopfer; A. Yang; L. von Wedel…

2004-08-01T23:59:59.000Z

198

Automated Simulation of Organic Photovoltaic Solar Cells; Analytical Tool for Organic Photovoltaic Solar Cells.  

E-Print Network [OSTI]

?? This project is an extension of a pre-existing simulation program (‘Simulation_2dioden’). This simulation program was first developed in Konarka Technologies. The main purpose of… (more)

Pendyala, Raghu Kishore

2008-01-01T23:59:59.000Z

199

A computational fluid dynamics model for wind simulation: model implementation and experimental validation  

Science Journals Connector (OSTI)

To provide physically based wind modelling for wind erosion research at regional scale, a 3D computational fluid dynamics (CFD) wind model was developed. The model was programmed ... analysis and modelling tool (...

Zhuo-dong Zhang; Ralf Wieland; Matthias Reiche…

2012-04-01T23:59:59.000Z

200

A Numerical Model for the Dynamic Simulation of a Recirculation Single-Effect Absorption Chiller  

E-Print Network [OSTI]

A Numerical Model for the Dynamic Simulation of a Recirculation Single- Effect Absorption Chiller A dynamic model for the simulation of a new single-effect water/lithium bromide absorption chiller. Keywords: absorption; chiller; modelling; transient; water-lithium bromide; falling film hal-00713904

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Molecular Dynamics Simulation of Hydrogen Storage with Single Walled Carbon Nanotubes  

E-Print Network [OSTI]

Molecular Dynamics Simulation of Hydrogen Storage with Single Walled Carbon Nanotubes Shigeo MARUYAMA #12;The hydrogen storage mechanism of SWNTs was studied through molecular dynamics simulations,12) Fig. 6 Hydrogen storage inside each SWNT #12;Table 1 Potential parameters between SWNTs Tube d0 [Ã?

Maruyama, Shigeo

202

A Molecular Dynamics Simulation of Hydrogen Storage by SWNTs Tatsuto Kimuraa  

E-Print Network [OSTI]

A Molecular Dynamics Simulation of Hydrogen Storage by SWNTs Tatsuto Kimuraa and Shigeo Maruyamab of efficient hydrogen storage [1] with SWNTs [2,3] was studied through classical molecular dynamics simulations adsorbed hydrogen molecules was almost proportional to the number of carbon atoms, and the storage amount

Maruyama, Shigeo

203

Molecular Dynamics Simulations of Laser Induced Incandescence Dr. Adri van Duin  

E-Print Network [OSTI]

Molecular Dynamics Simulations of Laser Induced Incandescence (LII) Dr. Adri van Duin Associate of Engineering. Laser Induced Incandescence (LII) is a popular method to estimate the properties of soot. Molecular Dynamics Simulations of Laser-Induced Incandescence of Soot Using an Extended ReaxFF Reactive

Bjørnstad, Ottar Nordal

204

Effect of Hydrodynamic Interactions on DNA Dynamics in Extensional Flow: Simulation and Single Molecule Experiment  

E-Print Network [OSTI]

a combination of single molecule experimental techniques and Brownian dynamics (BD) simulation to investigate, and chain stretch in strong flows. More recently, the advent of single molecule visualizations using. A careful coupling of single molecule visualization and Brownian dynamics simulation of polymer chains

Shaqfeh, Eric

205

Molecular Dynamics Simulation of Nucleation of SWNT from a Metal Particle on a Substrate  

E-Print Network [OSTI]

a transition metal cluster on a substrate is studied using classical molecular dynamics (MD) simulations between pure metal and metal-carbide. Graphite structure gradually precipitates from the edgeMolecular Dynamics Simulation of Nucleation of SWNT from a Metal Particle on a Substrate Yasushi

Maruyama, Shigeo

206

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

207

An Energy-Aware Simulation Model and Transaction Protocol for Dynamic Workload Distribution in Mobile Ad Hoc Networks1  

E-Print Network [OSTI]

An Energy-Aware Simulation Model and Transaction Protocol for Dynamic Workload Distribution California {tari, prong, pedram}@usc.edu Abstract This paper introduces a network simulation model

Pedram, Massoud

208

Note: Local thermal conductivities from boundary driven non-equilibrium molecular dynamics simulations  

SciTech Connect (OSTI)

We report non-equilibrium molecular dynamics simulations of heat transport in models of molecular fluids. We show that the “local” thermal conductivities obtained from non-equilibrium molecular dynamics simulations agree within numerical accuracy with equilibrium Green-Kubo computations. Our results support the local equilibrium hypothesis for transport properties. We show how to use the local dependence of the thermal gradients to quantify the thermal conductivity of molecular fluids for a wide range of thermodynamic states using a single simulation.

Bresme, F., E-mail: f.bresme@imperial.ac.uk [Department of Chemistry, Chemical Physics Section, Imperial College London, London SW7 2AZ (United Kingdom); Department of Chemistry, Norwegian University of Science and Technology, Trondheim (Norway); Armstrong, J., E-mail: j.armstrong@imperial.ac.uk [Department of Chemistry, Chemical Physics Section, Imperial College London, London SW7 2AZ (United Kingdom)

2014-01-07T23:59:59.000Z

209

Single molecule simulations in complex geometries with embedded dynamic one-dimensional structures  

E-Print Network [OSTI]

Single molecule simulations in complex geometries with embedded dynamic one-dimensional structures and shrink. In this paper we present a simulation algorithm that combines single molecule simula- tions in three-dimensional space with single molecule simulations on one-dimensional structures of arbitrary

Flener, Pierre

210

The Optimal Golf Swing An exercise in simulation of dynamic systems  

E-Print Network [OSTI]

correct handling is critical. Examples are flight-simulators and the training of operators in large power Dynamic systems have many applications, and simulators may be used for training personnel in cases where of true feeling the operators experience during the simulator training d the efficiency and accuracy

Mosegaard, Klaus

211

Diffusive Dynamics of Water inside Hydrophobic Carbon Micropores Studied by Neutron Spectroscopy and Molecular Dynamics Simulation  

E-Print Network [OSTI]

When water molecules are confined to nanoscale spacings, such as in the nanometer size pores of activated carbon fiber (ACF), their freezing point gets suppressed down to very low temperatures ($\\sim$ 150 K), leading to a metastable liquid state with remarkable physical properties. We have investigated the ambient pressure diffusive dynamics of water in microporous Kynol\\texttrademark ACF-10 (average pore size $\\sim$11.6 {\\AA}, with primarily slit-like pores) from temperature $T=$ 280 K in its stable liquid state down to $T=$ 230 K into the metastable supercooled phase. The observed characteristic relaxation times and diffusion coefficients are found to be respectively higher and lower than those in bulk water, indicating a slowing down of the water mobility with decreasing temperature. The observed temperature-dependent average relaxation time $$ when compared to previous findings indicate that it is the size of the confining pores - not their shape - that primarily affects the dynamics of water for pore sizes larger than 10 {\\AA}. The experimental observations are compared to complementary molecular dynamics simulations of a model system, in which we studied the diffusion of water within the 11.6 {\\AA} gap of two parallel graphene sheets. We find generally a reasonable agreement between the observed and calculated relaxation times at the low momentum transfer $Q$ ($Q\\le 0.9$ \\AA${^{-1}}$). At high $Q$ however, where localized dynamics becomes relevant, this ideal system does not satisfactorily reproduce the measurements. The best agreement is obtained for the diffusion parameter $D$ associated with the hydrogen-site when a representative stretched exponential function, rather than the standard bi-modal exponential model, is used to parameterize the self-correlation function $I(Q,t)$.

S. O. Diallo; L. Vlcek; E. Mamontov; J. K. Keum; Jihua Chen; J. S. Hayes Jr.; A. A. Chialvo

2014-12-15T23:59:59.000Z

212

PARTNERSHIP FOR THE DEVELOPMENT OF NEXT GENERATION SIMULATION TOOLS TO EVALUATE CEMENTITIOUS BARRIERS AND MATERIALS USED IN NUCLEAR APPLICATION - 8388  

SciTech Connect (OSTI)

The US DOE has initiated a multidisciplinary cross cutting project to develop a reasonable and credible set of tools to predict the structural, hydraulic and chemical performance of cement barriers used in nuclear applications over extended time frames (e.g., > 100 years for operating facilities and > 1000 years for waste management). A partnership that combines DOE, NRC, academia, private sector, and international expertise has been formed to accomplish the project objectives by integrating existing information and realizing advancements where necessary. The set of simulation tools and data developed under this project will be used to evaluate and predict the behavior of cementitious barriers used in near surface engineered waste disposal systems, e.g., waste forms, containment structures, entombments and environmental remediation, including decontamination and decommissioning (D&D) activities. The simulation tools will also support analysis of structural concrete components of nuclear facilities (spent fuel pools, dry spent fuel storage units, and recycling facilities, e.g., fuel fabrication, separations processes). Simulation parameters will be obtained from prior literature and will be experimentally measured under this project, as necessary, to demonstrate application of the simulation tools for three prototype applications (waste form in concrete vault, high level waste tank grouting, and spent fuel pool). Test methods and data needs to support use of the simulation tools for future applications will be defined. This is a national issue that affects all waste disposal sites that use cementitious waste forms and structures, decontamination and decommissioning activities, service life determination of existing structures, and design of future public and private nuclear facilities. The problem is difficult because it requires projecting conditions and responses over extremely long times. Current performance assessment analyses show that engineered barriers are typically the primary control to prevent the release of radionuclides from nuclear facilities into the environment. In the absence of an adequate predictive tool, assessments cannot fully incorporate the effectiveness of the concrete barriers, and the inventory of radionuclides (especially the long-lived radionuclides) that may be safely disposed of in shallow land disposal and the predicted service life of operating nuclear facilities. This project is 5 year effort focused on reducing uncertainties associated with current methodologies for assessing cementitious barrier performance and increasing the consistency and transparency of the assessment process. The results of this project will enable improved risk-informed, performance-based decision making, and supports several of the strategic initiatives in the DOE-EM Engineering & Technology Roadmap.

Langton, C; Richard Dimenna, R

2008-01-29T23:59:59.000Z

213

Development of Design and Simulation Tool for Hybrid Geothermal Heat Pump System  

Broader source: Energy.gov [DOE]

This project will expand Expand eQUEST, a building energy analysis software with latest implementation of DOE-2, for simulations of HGSHP systems and improve its existing simulation capabilities for ordinary GSHP systems.

214

EnergyGauge USA: A Residential Building Energy Simulation Design Tool  

E-Print Network [OSTI]

simulation in less than 20 seconds. A simplified user interface allows buildings to be quickly defined while bringing the computing power and accuracy of an hourly computer simulation to builders, designers and raters....

Fairey, P.; Vieira, R. K.; Parker, D. S.; Hanson, B.; Broman, P. A.; Grant, J. B.; Fuehrlein, B.; Gu, L.

2002-01-01T23:59:59.000Z

215

Agent-based simulation of electricity markets: a survey of tools  

Science Journals Connector (OSTI)

Agent-based simulation has been a popular technique in modeling and analyzing electricity markets in recent years. The main objective of this paper is to study existing agent-based simulation packages for electricity markets. We first provide an overview ... Keywords: Adaptation, Agent-based simulation, Artificial life, Electricity market, Swarm intelligence

Zhi Zhou; Wai Kin Chan; Joe H. Chow

2007-12-01T23:59:59.000Z

216

EnergyPlus as a forensic tool: Thermal reconstruction of a crime scene using calibrated simulation  

Science Journals Connector (OSTI)

This study utilized energy simulation in support of a forensic pathology time-of-death analysis for a corpse discovered in a single-family residence two years prior to the study. In order to produce an accurate estimate of the interior temperature profile ... Keywords: Energy model calibration, energy model accuracy, free-floating energy simulation, legal application of thermal simulation

Nathan Brown, M Susan Ubbelohde, George Loisos, Santosh Philip, Ibone Santiago

2014-08-01T23:59:59.000Z

217

A Research Code for Dynamic Power System Simulation and Analysis Steve Schaffer, Kevin Wedeward and Steven Ball  

E-Print Network [OSTI]

], and the object- oriented modeling language Modelica was chosen to create a library and graphically of states. This paper reports on the basic features and the various simulation and analysis tools that have access to simulation options, model components and analysis tools. The simulation can be used for both

Wedeward, Kevin

218

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities  

SciTech Connect (OSTI)

This paper assesses the accuracy of the simplified frame cavity conduction/convection and radiation models presented in ISO 15099 and used in software for rating and labeling window products. Temperatures and U-factors for typical horizontal window frames with internal cavities are compared; results from Computational Fluid Dynamics (CFD) simulations with detailed radiation modeling are used as a reference. Four different frames were studied. Two were made of polyvinyl chloride (PVC) and two of aluminum. For each frame, six different simulations were performed, two with a CFD code and four with a building-component thermal-simulation tool using the Finite Element Method (FEM). This FEM tool addresses convection using correlations from ISO 15099; it addressed radiation with either correlations from ISO 15099 or with a detailed, view-factor-based radiation model. Calculations were performed using the CFD code with and without fluid flow in the window frame cavities; the calculations without fluid flow were performed to verify that the CFD code and the building-component thermal-simulation tool produced consistent results. With the FEM-code, the practice of subdividing small frame cavities was examined, in some cases not subdividing, in some cases subdividing cavities with interconnections smaller than five millimeters (mm) (ISO 15099) and in some cases subdividing cavities with interconnections smaller than seven mm (a breakpoint that has been suggested in other studies). For the various frames, the calculated U-factors were found to be quite comparable (the maximum difference between the reference CFD simulation and the other simulations was found to be 13.2 percent). A maximum difference of 8.5 percent was found between the CFD simulation and the FEM simulation using ISO 15099 procedures. The ISO 15099 correlation works best for frames with high U-factors. For more efficient frames, the relative differences among various simulations are larger. Temperature was also compared, at selected locations on the frames. Small differences was found in the results from model to model. Finally, the effectiveness of the ISO cavity radiation algorithms was examined by comparing results from these algorithms to detailed radiation calculations (from both programs). Our results suggest that improvements in cavity heat transfer calculations can be obtained by using detailed radiation modeling (i.e. view-factor or ray-tracing models), and that incorporation of these strategies may be more important for improving the accuracy of results than the use of CFD modeling for horizontal cavities.

Gustavsen, Arlid; Kohler, Christian; Dalehaug, Arvid; Arasteh, Dariush

2008-12-01T23:59:59.000Z

219

Instructor authoring tool : a step towards promoting dynamic lecture-style classrooms  

E-Print Network [OSTI]

The Instructor Authoring Tool of the Classroom Learning Partner project provides an efficient tool for university professors and other teachers of lecture-style classrooms to construct lecture slides that can easily ...

Chen, Jessie I

2006-01-01T23:59:59.000Z

220

Dyna-CLUE Model Improvement Based on Exponential Smoothing Method and Land Use Dynamic Simulation  

Science Journals Connector (OSTI)

Response variables and their driving factors often vary with time in the process of land use dynamic simulation; however, there are few existing literatures mentioned it.In order to evaluate the impact of time fa...

Minghao Liu; Yaoxing Wang; Donghong Li…

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Lattice Boltzmann simulation to study multiple bubble dynamics Amit Gupta, Ranganathan Kumar *  

E-Print Network [OSTI]

Lattice Boltzmann simulation to study multiple bubble dynamics Amit Gupta, Ranganathan Kumar Keywords: Lattice Boltzmann Bubble Two-phase Coalescence a b s t r a c t Lattice Boltzmann method (LBM) has

Gupta, Amit

222

Finite Element Modelling and Molecular Dynamic Simulations of Carbon nanotubes/ Polymer Composites  

E-Print Network [OSTI]

Modeling of single-walled carbon nanotubes, multi-walled nanotubes and nanotube reinforced polymer composites using both the Finite Element method and the Molecular Dynamic simulation technique is presented. Nanotubes subjected to mechanical loading...

Gaddamanugu, Dhatri

2010-07-14T23:59:59.000Z

223

Research on propeller dynamic load simulation system of electric propulsion ship  

Science Journals Connector (OSTI)

A dynamic marine propeller simulation system was developed, which is ... requirement of theory research and engineering design of marine electric propulsion system. By applying an actual ship parameter...J? ? K ...

Hui Huang ? ?; Ai-di Shen ???; Jian-xin Chu ???

2013-04-01T23:59:59.000Z

224

Correlation of chemical shifts predicted by molecular dynamics simulations for partially disordered proteins  

Science Journals Connector (OSTI)

There has been a longstanding interest in being able to accurately predict NMR chemical shifts from structural data. Recent studies have focused on using molecular dynamics (MD) simulation data as input for impro...

Jerome M. Karp; Ertan Erylimaz; David Cowburn

2014-11-01T23:59:59.000Z

225

Parallel Simulation of Subsonic Fluid Dynamics on a Cluster of Workstations  

E-Print Network [OSTI]

An effective approach of simulating fluid dynamics on a cluster of non- dedicated workstations is presented. The approach uses local interaction algorithms, small communication capacity, and automatic migration of parallel ...

Skordos, Panayotis A.

1995-12-01T23:59:59.000Z

226

Nonequilibrium molecular dynamics simulations of confined fluids in contact with the bulk  

E-Print Network [OSTI]

Nonequilibrium molecular dynamics simulations of confined fluids in contact with the bulk Luzheng Zhang, Ramkumar Balasundaram,a) and Stevin H. Gehrke Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506 Shaoyi Jiangb) Department of Chemical Engineering, University

Zhang, Luzheng

227

Ab Initio Molecular Dynamics Simulations of Low-Energy Recoil...  

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

A variety of different defect configurations are created, consisting mainly of vacancies and interstitials. Charge transfer occurs during the dynamic displacement process....

228

Dynamic simulation on collision between ship and offshore wind turbine  

Science Journals Connector (OSTI)

By using ABAQUS/Explicit, the dynamic process of an offshore wind turbine(OWT) stricken by a ship of 5000DWT...

Hongyan Ding ???; Qi Zhu ? ?; Puyang Zhang ???

2014-02-01T23:59:59.000Z

229

LSRM - a tool for logic simulation of RISC-based microprocessor  

E-Print Network [OSTI]

, are proposed. A prototype, called LSRM (a Logic Simulator for RISC-based Microprocessor), is also designed and implemented in SUN/UNIX environment. LSRM consists of a graphical user interface and a simulator. The user interface is built on the X...

Jiang, Xiaohua

2012-06-07T23:59:59.000Z

230

HYBRID GROUND SOURCE HEAT PUMP SYSTEM SIMULATION USING VISUAL MODELING TOOL FOR HVACSIM+  

E-Print Network [OSTI]

, and plotting the output are also included. INTRODUCTION HVACSIM+, which stands for `HVAC SIMulation PLUS other systems', is a non-proprietary simulation package developed at the National Institute of Standards and Technology (NIST), Gaithersburg, Maryland, U.S.A. It is capable of modeling HVAC (heating, ventilation

231

Hybrid Electro-Mechanical Simulation Tool for Wind Turbine Generators: Preprint  

SciTech Connect (OSTI)

This paper describes the use of MATLAB/Simulink to simulate the electrical and grid-related aspects of a WTG and the FAST aero-elastic wind turbine code to simulate the aerodynamic and mechanical aspects of the WTG. The combination of the two enables studies involving both electrical and mechanical aspects of the WTG.

Singh, M.; Muljadi, E.; Jonkman, J.

2013-05-01T23:59:59.000Z

232

Verification of the Effectiveness of VSOP-2 Phase Referencing with a Newly Developed Simulation Tool, ARIS  

Science Journals Connector (OSTI)

......right-bottom plot represent a simulated grid. The astrometric accuracy for the 60-s...the right bottom plot represent simulated grid. At this stage let us consider possible...gyros (CMGs) with a single-gimbaled flywheel spinning at a constant angular rate are......

Yoshiharu Asaki; Hiroshi Sudou; Yusuke Kono; Akihiro Doi; Richard Dodson; Nicolas Pradel; Yasuhiro Murata; Nanako Mochizuki; Philip G. Edwards; Tetsuo Sasao; Edward B. Fomalont

2007-04-25T23:59:59.000Z

233

Experimental characterization of energetic material dynamics for multiphase blast simulation.  

SciTech Connect (OSTI)

Currently there is a substantial lack of data for interactions of shock waves with particle fields having volume fractions residing between the dilute and granular regimes, which creates one of the largest sources of uncertainty in the simulation of energetic material detonation. To close this gap, a novel Multiphase Shock Tube has been constructed to drive a planar shock wave into a dense gas-solid field of particles. A nearly spatially isotropic field of particles is generated in the test section by a gravity-fed method that results in a spanwise curtain of spherical 100-micron particles having a volume fraction of about 19%. Interactions with incident shock Mach numbers of 1.66, 1.92, and 2.02 were achieved. High-speed schlieren imaging simultaneous with high-frequency wall pressure measurements are used to reveal the complex wave structure associated with the interaction. Following incident shock impingement, transmitted and reflected shocks are observed, which lead to differences in particle drag across the streamwise dimension of the curtain. Shortly thereafter, the particle field begins to propagate downstream and spread. For all three Mach numbers tested, the energy and momentum fluxes in the induced flow far downstream are reduced about 30-40% by the presence of the particle field. X-Ray diagnostics have been developed to penetrate the opacity of the flow, revealing the concentrations throughout the particle field as it expands and spreads downstream with time. Furthermore, an X-Ray particle tracking velocimetry diagnostic has been demonstrated to be feasible for this flow, which can be used to follow the trajectory of tracer particles seeded into the curtain. Additional experiments on single spherical particles accelerated behind an incident shock wave have shown that elevated particle drag coefficients can be attributed to increased compressibility rather than flow unsteadiness, clarifying confusing results from the historical database of shock tube experiments. The development of the Multiphase Shock Tube and associated diagnostic capabilities offers experimental capability to a previously inaccessible regime, which can provide unprecedented data concerning particle dynamics of dense gas-solid flows.

Beresh, Steven Jay; Wagner, Justin L.; Kearney, Sean Patrick; Wright, Elton K.; Baer, Melvin R.; Pruett, Brian Owen Matthew

2011-09-01T23:59:59.000Z

234

Atomic detail brownian dynamics simulations of concentrated protein...  

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

method. Concentrated solutions (30-40% volume fraction) of myoglobin, hemoglobin A, and sickle cell hemoglobin S were simulated, and static structure factors, oligomer formation,...

235

BEAM DYNAMICS SIMULATIONS FOR A DC GUN BASED INJECTOR F.Zhou 1,2,  

E-Print Network [OSTI]

BEAM DYNAMICS SIMULATIONS FOR A DC GUN BASED INJECTOR FOR PERL* F.Zhou 1,2, , I.Ben-Zvi2 , X for this machine are being extensively investigated at BNL. One of the possible options is photocathode DC gun. The schematic layout of a PERL DC gun based injector and its preliminary beam dynamics are presented

Brookhaven National Laboratory

236

Hybrid approach for including electronic and nuclear quantum effects in molecular dynamics simulations of hydrogen transfer  

E-Print Network [OSTI]

Hybrid approach for including electronic and nuclear quantum effects in molecular dynamics January 2001 A hybrid approach for simulating proton and hydride transfer reactions in enzymes coefficient and to investigate the real-time dynamics of reactive trajectories. This hybrid approach includes

Hammes-Schiffer, Sharon

237

Nonadiabatic Molecular Dynamics Simulations of the Energy Transfer between Building Blocks in a Phenylene Ethynylene Dendrimer  

E-Print Network [OSTI]

Nonadiabatic Molecular Dynamics Simulations of the Energy Transfer between Building Blocks E. Roitberg*, UniVersidad Nacional de Quilmes, Roque Saenz Pen~a 352, B1876BXD Bernal, Argentina, 2009 The ultrafast dynamics of electronic and vibrational energy transfer between two- and three

Tretiak, Sergei

238

Myoglobin-CO Conformational Substate Dynamics: 2D Vibrational Echoes and MD Simulations  

E-Print Network [OSTI]

Myoglobin-CO Conformational Substate Dynamics: 2D Vibrational Echoes and MD Simulations Kusai A over a range of temperatures. The A1 and A3 conformational substates of MbCO are found to have assignments for the MbCO conformational substates. INTRODUCTION Protein dynamics have been the focus of both

Fayer, Michael D.

239

Rapid hydrogen production from water using aluminum nanoclusters: A quantum molecular dynamics simulation study  

E-Print Network [OSTI]

Rapid hydrogen production from water using aluminum nanoclusters: A quantum molecular dynamics Available online 31 December 2013 Keywords: Hydrogen production Water Aluminum nanoclusters Quantum molecular dynamics simulation It is hoped that a hydrogen-on-demand generator may one day start with just

Southern California, University of

240

The Implementation of Industry Foundation Classes in Simulation Tools for the Building Industry  

SciTech Connect (OSTI)

Industry Foundation Classes (IFC) provide an environment of interoperability among IFC-compliant software applications in the architecture, engineering, construction, and facilities management (AEC/FM) industry. They allow building simulation software to automatically acquire building geometry and other building data from project models created with IFC compliant CAD software. They also facilitate direct exchange of input and output data with other simulation software. This paper discusses how simulation software can be made compliant with version 1.5 of the IFC. It also describes the immediate plans for expansion of IFC and the process of definition and addition of new classes to the model.

Bazjanac, Vladimir; Crawley, Drury B.

1997-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

A Virtual Test Facility for the Simulation of Dynamic Response in Materials  

Science Journals Connector (OSTI)

The Center for Simulating Dynamic Response of Materials at the California Institute of Technology is constructing a virtual shock physics facility for studying the response of various target materials to very strong shocks. The Virtual Test Facility ... Keywords: parallel computing, shock physics simulation

Julian Cummings; Michael Aivazis; Ravi Samtaney; Raul Radovitzky; Sean Mauch; Dan Meiron

2002-08-01T23:59:59.000Z

242

Proper Orthogonal Decomposition-Based Modeling, Analysis, and Simulation of Dynamic Wind Load  

E-Print Network [OSTI]

Proper Orthogonal Decomposition-Based Modeling, Analysis, and Simulation of Dynamic Wind Load.1061/ ASCE 0733-9399 2005 131:4 325 CE Database subject headings: Simulation; Wind loads; Buildings; Random on the decomposition of the covariance and XPSD matrices is presented. A physically meaningful linkage between the wind

Chen, Xinzhong

243

On the self-similarity assumption in dynamic models for large eddy simulations  

E-Print Network [OSTI]

that the present formulation of the DP is usually incompatible with its under- lying self-similarity assumption SSAOn the self-similarity assumption in dynamic models for large eddy simulations Daniele Carati eddy simulations and their underlying self-similarity assumption is discussed. The interpretation

Van Den Eijnden, Eric

244

Understanding graphene production by ionic surfactant exfoliation: A molecular dynamics simulation study  

E-Print Network [OSTI]

Understanding graphene production by ionic surfactant exfoliation: A molecular dynamics simulation simulated sodium dodecyl sulfate (SDS) surfactant/water þ bilayer graphene mixture system to investigate two mechanisms of graphene exfoliation: changing the interlayer distance and sliding away the relative distance

Simons, Jack

245

Integrating Models and Simulations of Continuous Dynamics into SysML  

E-Print Network [OSTI]

and the corresponding Modelica models; and the integration of simulation experiments with other SysML constructsIntegrating Models and Simulations of Continuous Dynamics into SysML Thomas Johnson1 Christiaan J.J. Paredis1 Roger Burkhart2 1 Systems Realization Laboratory The G. W. Woodruff School of Mechanical

246

Climate Dynamics Diagnosis of the Marine Low Cloud Simulation in the NCAR Community Earth System  

E-Print Network [OSTI]

-of-the-art coupled atmosphere-ocean models: the NCAR Community Earth System Model (CESM) and the NCEP Global of the Marine Low Cloud Simulation in the NCAR1 Community Earth System Model (CESM) and the NCEP Global2Climate Dynamics Diagnosis of the Marine Low Cloud Simulation in the NCAR Community Earth System

Bretherton, Chris

247

Computer simulations to classrooms: tools for change Noah S. Podolefsky, Katherine K. Perkins, & Wendy K. Adams  

E-Print Network [OSTI]

-0390 Abstract. This paper situates PhET computer simulations (sims) in a socio-cultural-historical context. Sims student learning through engaged exploration. We support our claims with data from studies of use of sims

Colorado at Boulder, University of

248

Design and Simulation for Architectural Geometry Figure 1: Daytime and nighttime scenes of designed roof by using the developed computational tools  

E-Print Network [OSTI]

roof by using the developed computational tools 031.PDF Keywords: Architectural Geometry, Procedural an innovative computational design tool used to edit architectural geometry interactively and demonstratesDesign and Simulation for Architectural Geometry Figure 1: Daytime and nighttime scenes of designed

249

Nonadiabatic molecular dynamics simulation: An approach based on quantum measurement picture  

E-Print Network [OSTI]

Mixed-quantum-classical molecular dynamics simulation implies an effective measurement on the electronic states owing to continuously tracking the atomic forces.Based on this insight, we propose a quantum trajectory mean-field approach for nonadiabatic molecular dynamics simulations. The new protocol provides a natural interface between the separate quantum and classical treatments, without invoking artificial surface hopping algorithm. Moreover, it also bridges two widely adopted nonadiabatic dynamics methods, the Ehrenfest mean-field theory and the trajectory surface-hopping method. Excellent agreement with the exact results is illustrated with representative model systems, including the challenging ones for traditional methods.

Wei Feng; Luting Xu; Xin-Qi Li; Weihai Fang; YiJing Yan

2013-12-17T23:59:59.000Z

250

Water dynamical anomalies evidenced by molecular-dynamics simulations at the solvent-protein interface  

Science Journals Connector (OSTI)

We present a computer simulation picture of the dynamical behavior, at room temperature, of water in the region close to a protein surface. We analyzed the probability distribution of water molecules diffusing near the surface, and we found that it deviates from a Gaussian, which is predicted for Brownian particles. Consistently, the mean square displacements of water oxygens show a sublinear trend with time. Moreover, the relaxation of hydration layers around the whole protein is found to follow a stretched exponential decay, typical of complex systems, which could as well be ascribed to the non-Gaussian shape of the propagator. In agreement with such findings, the analysis of water translational and reorientational diffusion showed that not only are the solvent molecule motions hindered in the region close to the protein surface, but also the very nature of the particle diffusive processes, both translational and rotational, is affected. The deviations from the bulk water properties, which put into evidence a deep influence exerted by the protein on the solvent molecule motion, are discussed in connection with the presence of spatial (protein surface roughness) and temporal (distribution of water residence times) disorder inherent in the system.

Claudia Rocchi; Anna Rita Bizzarri; Salvatore Cannistraro

1998-03-01T23:59:59.000Z

251

Structural models of bioactive glasses from molecular dynamics simulations  

Science Journals Connector (OSTI)

...to adsorb and dissociate a water molecule (Tilocca Cormack 2008...the available computational power steadily grows, it will become...surface of bioactive glasses: water adsorption and reactivity...soda-lime silicate glasses by Car-Parrinello molecular dynamics...

2009-01-01T23:59:59.000Z

252

Molecular dynamics simulation of phosphorylation-induced conformational transitions in the mycobacterium tuberculosis response regulator PrrA  

SciTech Connect (OSTI)

Phosphorylation-activated modulation of response regulators (RR) is predominantly used by bacteria as a strategy in regulating their two-component signaling (TCS) systems, the underlying molecular mechanisms are however far from fully understood. In this work we have conducted a molecular dynamics (MD) simulation of the phosphorylation-induced conformational transitions of RRs with the Mycobacterium Tuberculosis PrrA as a particular example. Starting from the full-length inactive structure of PrrA we introduced a local disturbance by phosphorylating the conserved aspartic acid residue, Asp-58, in the regulatory domain. A Go-model-type algorithm packaged with AMBER force fields was then applied to simulate the dynamics upon phosphorylation. The MD simulation shows that the phosphorylation of Asp-58 facilitates PrrA, whose inactive state has a compact conformation with a closed interdomain interface, to open up with its interdomain separation being increased by an average of about 1.5 {angstrom} for a simulation of 20 ns. The trans-activation loop, which is completely buried within the interdomain interface in the inactive PrrA, is found to become more exposed with the phosphorylated structure as well. These results provide more structural details of how the phosphorylation of a local aspartate activates PrrA to undergo a global conformational rearrangement toward its extended active state. This work also indicates that MD simulations can serve as a fast tool to unravel the regulation mechanisms of all RRs, which is especially valuable when the structures of full-length active RRs are currently unavailable.

Chen, Guo [Los Alamos National Laboratory; Mcmahon, Benjamin H [Los Alamos National Laboratory; Tung, Chang - Shung [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

253

Multiplatform Dynamic System Simulation of a DC-DC Converter.  

E-Print Network [OSTI]

??The work presented in this paper focuses on the usability testing for the Open-Modelica. The modeling and simulation of the BMR450 DC-DC converter is also… (more)

Song, Wenpeng

2012-01-01T23:59:59.000Z

254

Investigating dynamic underground coal fires by means of numerical simulation  

Science Journals Connector (OSTI)

......is the key to successful prediction of various combustion processes (Hjertager 1986). Ten years ago, limited computer...Blasi C.D. ,1993. Modeling and simulation of combustion processes of charring and non-charring solid fuels, Prog......

S. Wessling; W. Kessels; M. Schmidt; U. Krause

2008-01-01T23:59:59.000Z

255

Extended Lagrangian quantum molecular dynamics simulations of shock-induced chemistry in hydrocarbons  

SciTech Connect (OSTI)

A set of interatomic potentials for hydrocarbons that are based upon the self-consistent charge transfer tight-binding approximation to density functional theory have been developed and implemented into the quantum molecular dynamics code ''LATTE''. The interatomic potentials exhibit an outstanding level of transferability and have been applied in molecular dynamics simulations of tert-butylacetylene under thermodynamic conditions that correspond to its single-shock Hugoniot. We have achieved precise conservation of the total energy during microcanonical molecular dynamics trajectories under incomplete convergence via the extended Lagrangian Born-Oppenheimer molecular dynamics formalism. In good agreement with the results of a series of flyer-plate impact experiments, our SCC-TB molecular dynamics simulations show that tert-butylactylene molecules polymerize at shock pressures around 6.1 GPa.

Sanville, Edward J [Los Alamos National Laboratory; Bock, Nicolas [Los Alamos National Laboratory; Challacombe, William M [Los Alamos National Laboratory; Cawkwell, Marc J [Los Alamos National Laboratory; Niklasson, Anders M N [Los Alamos National Laboratory; Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Stephen [Los Alamos National Laboratory; Sewell, Thomas D [UNIV OF MISSOURI

2010-01-01T23:59:59.000Z

256

Dynamic Human Reliability Analysis: Benefits and Challenges of Simulating Human Performance  

SciTech Connect (OSTI)

To date, there has been considerable work on dynamic event trees and other areas related to dynamic probabilistic safety assessment (PSA). The counterpart to these efforts in human reliability analysis (HRA) has centered on the development of specific methods to account for the dynamic nature of human performance. In this paper, the author posits that the key to dynamic HRA is not in the development of specific methods but in the utilization of cognitive modeling and simulation to produce a framework of data that may be used in quantifying the likelihood of human error. This paper provides an overview of simulation approaches to HRA; reviews differences between first, second, and dynamic generation HRA; and outlines potential benefits and challenges of this approach.

R. L. Boring

2007-06-01T23:59:59.000Z

257

Computational Fluid Dynamics Simulation of Open-Channel Flows Over Bridge-Decks Under Various Flooding Conditions  

E-Print Network [OSTI]

. This study simulates limited scaled experimental data conducted elsewhere for bridge flooding in open channel simulation, Computational fluid dynamics, Flooding flows, Turbulence modeling, VOF modeling. 1. IntroductionComputational Fluid Dynamics Simulation of Open-Channel Flows Over Bridge-Decks Under Various

Kostic, Milivoje M.

258

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

259

AMIP Simulation with the CAM4 Spectral Element Dynamical Core  

SciTech Connect (OSTI)

We evaluate the climate produced by the Community Earth System Model, version 1, running with the new spectral-element atmospheric dynamical core option. The spectral-element method is congured to use a cubed-sphere grid, providing quasi-uniform resolution over the sphere, increased parallel scalability and removing the need for polar filters. It uses a fourth order accurate spatial discretization which locally conserves mass and moist total energy. Using the Atmosphere Model Intercomparison Project protocol, we compare the results from the spectral-element dy- namical core with those produced by the default nite-volume dynamical core and with observations.

Evans, Katherine J [ORNL; Lauritzen, Peter [National Center for Atmospheric Research (NCAR); Mishra, Saroj [National Center for Atmospheric Research (NCAR); Neale, Rich [National Center for Atmospheric Research (NCAR); Taylor, Mark [Sandia National Laboratories (SNL); Tribbia, Joe [National Center for Atmospheric Research (NCAR)

2013-01-01T23:59:59.000Z

260

Ion and Electron Dynamics in Nonlinear PIC Simulations  

SciTech Connect (OSTI)

ITG and ETG turbulence is investigated with the nonlinear global PIC code ORB5. The large variety of numerical schemes and simulations domains used has sometimes lead to important discrepancies in the transport predictions. In order to discuss these disagreements, emphasis must be put on ways to check the numerical accuracy, such as energy conservation and numerical noise measurement. This paper therefore presents benchmarks, new algorithms and a noise diagnostic. After having demonstrated the numerical quality of our simulations, 2 topics are visited: the unclear role of the parallel nonlinearity and the transport level in ETG turbulence, for which predictions differing by one order of magnitude had been made elsewhere.

Jolliet, S.; Angelino, P.; Tran, T. M.; McMillan, B. F.; Sauter, O.; Villard, L. [Ecole Polytechnique Federale de Lausanne, Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, CH-1015 Lausanne (Switzerland); Bottino, A.; Peeters, A. G.; Poli, E. [Max Planck Institut fuer Plasmaphysik, IPP-EURATOM Association, Garching (Germany); Hatzky, R. [Computer Center of the Max-Planck-Gesellschaft, D 85748 Garching (Germany)

2006-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

From Balanced Initial Occupant Distribution to Balanced Exit Usage in a Simulation Model of Pedestrian Dynamics  

E-Print Network [OSTI]

It is tested in this contribution if and to which extend a method of a pedestrian simulation tool that attempts to make pedestrians walk into the direction of estimated earliest arrival can help to automatically distribute pedestrians - who are initially distributed arbitrarily in the scenario - equally on the various exits of the scenario.

Kretz, Tobias

2012-01-01T23:59:59.000Z

262

Integrated Dynamic Simulation for Process Optimization and Control  

E-Print Network [OSTI]

wherever possible ­ Radiative heat transfer ­ Mass balance ­ Boundary layer transport ­ Surface adsorption;Schematics of Polysilicon RT-CVD Reactor MFC gas cylinder heating lamps RTP reactor RTP pumps 1st stage 2nd-level description ­ Reduced-order models to represent high complexity (e.g., reactor fluid dynamics, heat transfer

Rubloff, Gary W.

263

Darlington tritium removal facility and station upgrading plant dynamic process simulation  

SciTech Connect (OSTI)

Ontario Power Generation Nuclear (OPGN) has a 4 x 880 MWe CANDU nuclear station at its Darlington Nuclear Div. located in Bowmanville. The station has been operating a Tritium Removal Facility (TRF) and a D{sub 2}O station Upgrading Plant (SUP) since 1989. Both facilities were designed with a Distributed Control System (DCS) and programmable logic controllers (PLC) for process control. This control system was replaced with a DCS only, in 1998. A dynamic plant simulator was developed for the Darlington TRF (DTRF) and the SUP, as part of the computer control system replacement. The simulator was used to test the new software, required to eliminate the PLCs. The simulator is now used for operator training and testing of process control software changes prior to field installation. Dynamic simulation will be essential for the ITER isotope separation system, where the process is more dynamic than the relatively steady-state DTRF process. This paper describes the development and application of the DTRF and SUP dynamic simulator, its benefits, architecture, and the operational experience with the simulator. (authors)

Busigin, A. [NITEK USA, Inc., 6405 NW 77 PL, Parkland, FL 33067 (United States); Williams, G. I. D.; Wong, T. C. W.; Kulczynski, D.; Reid, A. [Ontario Power Generation Nuclear, Box 4000, Bowmanville, ON L1C 3Z8 (Canada)

2008-07-15T23:59:59.000Z

264

Numerical modelling of solid fuel combustion processes using advanced CFD-based simulation tools  

Science Journals Connector (OSTI)

Computational modelling of combustion processes has been the subject of coninuous research at the Institute of Process Engineering and Power Plant Technology (IVD) over the last two decades. To this end, finite-volume-based computer codes have been developed. In the present paper, some fundamental ideas and approaches of the applied mathematical models and the numerical methods are described, followed by some examples of typical applications of the procedures with special emphasis on the validation of simulation results. These examples show that the application of combustion simulation codes has been extended to comprise a wide range of several different areas ranging from huge bituminous coal-fired utility boilers for electricity production to decentralised small-scale furnaces and tile stove heating inserts for domestic heating.

Uwe Schnell

2001-01-01T23:59:59.000Z

265

Economic and environmental evaluation of microalgae biodiesel production using process simulation tools  

Science Journals Connector (OSTI)

Abstract This work introduces a systematic method for the economic and environmental analysis and design of new technologies applied to the 3rd generation (from microalgae) biodiesel production process. The evaluation method is based on the integrated use of process simulation techniques with economic and environmental models. The approach is applied to a new technology introduced by some of the authors, where the glycerol produced in the transesterification is used as carbon source for microalgae growth. Firstly, a state of the art biodiesel production plant in the process simulator it is modelled and the economical and environmental performance is computed. Then, the new technology is introduced and its performance are compared. The method presented is very useful for decision-makers in order to evaluate the inclusion of new technologies to improve the chemical process operation and topological designs.

Robert Brunet; David Carrasco; Eduardo Muñoz; Gonzalo Guillén-Gosálbez; Ioanis Katakis; Laureano Jiménez

2012-01-01T23:59:59.000Z

266

Dynamic simulation method for transmission and distribution planning  

Science Journals Connector (OSTI)

Under the conditions of liberalised market development optimisation role is not to be decreasing but even increasing. Basic definitions and model structure of optimisation system under market conditions is discussed in a paper, as well the experience ... Keywords: development optimisation, liberalised electricity market, power generation, power system planning, power system simulation, power transmission, risk analysis, uncertainty

Z. Krishans; I. Oleinikova; A. Mutule; J. Runcs

2006-12-01T23:59:59.000Z

267

Dynamic Deployment of Executing and Simulating Software Components  

E-Print Network [OSTI]

can reduce its processor power to conserve energy when its energy supply (i.e., battery) is low in the past, simulation merely mimicked some real-world behav- ior, we argue that in the future it will become necessary to intertwine the model world with the real world. This will be essential but not limited to cases

Egyed, Alexander

268

Periodic Boundary Conditions for Dislocation Dynamics Simulations in Three Dimensions  

E-Print Network [OSTI]

, the choice of initial configurations compatible with PBC and a consistent treatment of image stress of PBC for large-scale DD simulations in 3D. INTRODUCTION Treatment of boundary conditions or external interface (surface, crack, grain or phase boundary, etc.), it is necessary to account for stress

Cai, Wei

269

Building simulation approaches for the training of automated data analysis tools in building energy management  

Science Journals Connector (OSTI)

Abstract The field of building energy management, which monitors and analyses the energy use of buildings with the aim to control and reduce energy expenditure, is seeing a rapid evolution. Automated meter reading approaches, harvesting data at hourly or even half-hourly intervals, create a large pool of data which needs analysis. Computer analysis by means of machine learning techniques allows automated processing of this data, invoking expert analysis where anomalies are detected. However, machine learning always requires a historical dataset to train models and develop a benchmark to define what constitutes an anomaly. Computer analysis by means of building performance simulation employs physical principles to predict energy behaviour, and allows the assessment of the behaviour of buildings from a pure modelling background. This paper explores how building simulation approaches can be fused into energy management practice, especially with a view to the production of artificial bespoke benchmarks where historical profiles are not available. A real accommodation block, which is subject to monitoring, is used to gather an estimation of the accuracy of this approach. The findings show that machine learning from simulation models has a high internal accuracy; comparison with actual metering data shows prediction errors in the system (20%) but still achieves a substantial improvement over industry benchmark values.

Pieter de Wilde; Carlos Martinez-Ortiz; Darren Pearson; Ian Beynon; Martin Beck; Nigel Barlow

2013-01-01T23:59:59.000Z

270

Slow dynamics of a protein backbone in molecular dynamics simulation revealed by time-structure based independent component analysis  

SciTech Connect (OSTI)

We recently proposed the method of time-structure based independent component analysis (tICA) to examine the slow dynamics involved in conformational fluctuations of a protein as estimated by molecular dynamics (MD) simulation [Y. Naritomi and S. Fuchigami, J. Chem. Phys. 134, 065101 (2011)]. Our previous study focused on domain motions of the protein and examined its dynamics by using rigid-body domain analysis and tICA. However, the protein changes its conformation not only through domain motions but also by various types of motions involving its backbone and side chains. Some of these motions might occur on a slow time scale: we hypothesize that if so, we could effectively detect and characterize them using tICA. In the present study, we investigated slow dynamics of the protein backbone using MD simulation and tICA. The selected target protein was lysine-, arginine-, ornithine-binding protein (LAO), which comprises two domains and undergoes large domain motions. MD simulation of LAO in explicit water was performed for 1 ?s, and the obtained trajectory of C{sub ?} atoms in the backbone was analyzed by tICA. This analysis successfully provided us with slow modes for LAO that represented either domain motions or local movements of the backbone. Further analysis elucidated the atomic details of the suggested local motions and confirmed that these motions truly occurred on the expected slow time scale.

Naritomi, Yusuke [Department of Supramolecular Biology, Graduate School of Nanobioscience, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan)] [Department of Supramolecular Biology, Graduate School of Nanobioscience, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan); Fuchigami, Sotaro, E-mail: sotaro@tsurumi.yokohama-cu.ac.jp [Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan)] [Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan)

2013-12-07T23:59:59.000Z

271

Virtual control system environment: A modeling and simulation tool for process control systems  

SciTech Connect (OSTI)

The development of tools and techniques for security testing and performance testing of Process Control Systems (PCS) is needed since those systems are vulnerable to the same classes of threats as other networked computer systems. In practice, security testing is difficult to perform on operational PCS because it introduces an unacceptable risk of disruption to the critical systems (e.g., power grids) that they control. In addition, the hardware used in PCS is often expensive, making full-scale mockup systems for live experiments impractical. A more flexible approach to these problems can be provided through test beds that provide the proper mix of real, emulated, and virtual elements to model large, complex systems such as critical infrastructures. This paper describes a 'Virtual Control System Environment' that addresses these issues. (authors)

Lee, E.; Michalski, J.; Sholander, P.; Van Leeuwen, B. [Sandia National Laboratories, Albuquerque, NM 87111 (United States)

2006-07-01T23:59:59.000Z

272

Time-Dependent Properties of Liquid Water:? A Comparison of Car?Parrinello and Born?Oppenheimer Molecular Dynamics Simulations  

Science Journals Connector (OSTI)

Time-Dependent Properties of Liquid Water:? A Comparison of Car?Parrinello and Born?Oppenheimer Molecular Dynamics Simulations ... Dynamical information of water interacting with its local environment can be gleaned from the vibrational power spectrum. ...

I-Feng W. Kuo; Christopher J. Mundy; Matthew J. McGrath; J. Ilja Siepmann

2006-07-27T23:59:59.000Z

273

Molecular dynamics simulations of the interaction of glucose with imidazole in aqueous solution  

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

Molecular dynamics simulations of the interaction of glucose with imidazole in Molecular dynamics simulations of the interaction of glucose with imidazole in aqueous solution Mo Chen, Yannick J. Bomble, Michael E. Himmel, John W. Brady PII: S0008-6215(11)00592-1 DOI: 10.1016/j.carres.2011.12.008 Reference: CAR 6026 To appear in: Carbohydrate Research Received Date: 15 June 2011 Revised Date: 22 November 2011 Accepted Date: 8 December 2011 Please cite this article as: Chen, M., Bomble, Y.J., Himmel, M.E., Brady, J.W., Molecular dynamics simulations of the interaction of glucose with imidazole in aqueous solution, Carbohydrate Research (2011), doi: 10.1016/j.carres. 2011.12.008 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and

274

Molecular dynamics simulation of chains mobility in polyethylene crystal  

E-Print Network [OSTI]

The mobility of polymer chains in perfect polyethylene (PE) crystal was calculated as a function of temperature and chain length through Molecular dynamics (MD) in united atom approximation. The results demonstrate that the chain mobility drastically increases in the vicinity of the phase transition from the orthorhombic to quasi-hexagonal phase. In the quasi-hexagonal phase, the chain mobility is almost independent on temperature and inversely proportional to the chain length.

V. I. Sultanov; V. V. Atrazhev; D. V. Dmitriev; S. F. Burlatsky

2014-01-17T23:59:59.000Z

275

Helmet Streamers with Triple Structures: Simulations of resistive dynamics  

E-Print Network [OSTI]

Recent observations of the solar corona with the LASCO coronagraph on board of the SOHO spacecraft have revealed the occurrence of triple helmet streamers even during solar minimum, which occasionally go unstable and give rise to large coronal mass ejections. There are also indications that the slow solar wind is either a combination of a quasi-stationary flow and a highly fluctuating component or may even be caused completely by many small eruptions or instabilities. As a first step we recently presented an analytical method to calculate simple two-dimensional stationary models of triple helmet streamer configurations. In the present contribution we use the equations of time- dependent resistive magnetohydrodynamics to investigate the stability and the dynamical behaviour of these configurations. We particularly focus on the possible differences between the dynamics of single isolated streamers and triple streamers and on the way in which magnetic reconnection initiates both small scale and large scale dynamical behaviour of the streamers. Our results indicate that small eruptions at the helmet streamer cusp may incessantly accelerate small amounts of plasma without significant changes of the equilibrium configuration and might thus contribute to the non-stationary slow solar wind. On larger time and length scales, large coronal eruptions can occur as a consequence of large scale magnetic reconnection events inside the streamer configuration. Our results also show that triple streamers are usually more stable than a single streamer.

T. Wiegelmann; K. Schindler; T. Neukirch

2008-01-21T23:59:59.000Z

276

NREL: Dynamic Maps, GIS Data, and Analysis Tools - MapSearch  

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

Bookmark and Share Bookmark and Share MapSearch MapSearch Logo is a computer monitor with a magnifying glass suspended in the air before it. Use our MapSearch to easily search our collection of maps created by the Geographic Information System (GIS) team. Please use the search box and the filters on the left and right of the screen to limit results. Notice: The current tool works best in Firefox and may result in errors if opened using Microsoft Internet Explorer. June 2013 - The NREL GIS team has released a new beta version of the Mapsearch tool. This new beta version should eliminate some of the browser issues experienced with the current tool. The beta version is designed to work with NREL's OpenEI so users will have one site to search and view NREL created maps. If you have any feeback or comments on this new beta site, contact the Webmaster. While testing is done on this new beta version, the current MapSearch tool is still available. The following instructions apply to the current tool. launch

277

Thermophysical properties of warm dense hydrogen using quantum molecular dynamics simulations  

Science Journals Connector (OSTI)

We study the thermophysical properties of warm dense hydrogen by using quantum molecular dynamics simulations. Results are presented for the pair distribution functions, the equation of state, and the Hugoniot curve. From the dynamic conductivity, we derive the dc electrical conductivity and the reflectivity. We compare with available experimental data and predictions of the chemical picture. In particular, we discuss the nonmetal-to-metal transition, which occurs at about 40 GPa in the dense fluid.

Bastian Holst, Ronald Redmer, and Michael P. Desjarlais

2008-05-09T23:59:59.000Z

278

Dynamic Simulation of Startup in Ethyl tert-Butyl Ether Reactive Distillation with Input Multiplicity  

Science Journals Connector (OSTI)

Dynamic Simulation of Startup in Ethyl tert-Butyl Ether Reactive Distillation with Input Multiplicity ... However, smaller internal rates inside the column that result from lower reboiler and condenser duty could increase the potential risk of flooding in the column and reduce the availability of reactants in the reactive section. ... Column simulations performed using both Pro/II and SpeedUp showed excellent agreement with previously published exptl. ...

Budi H. Bisowarno; Moses O. Tadé

2000-05-09T23:59:59.000Z

279

Simulation of ultrafast heating induced structural dynamics using a one-dimensional spring model  

Science Journals Connector (OSTI)

We developed a one-dimensional spring model to study the dynamics of lattice motion upon ultrafast laser heating. Using this model, we simulated atomic positions as a function of time in a free-standing thin monoatomic metal film as well as in a thin film on a substrate. In particular, we studied how the electronic thermal stress influences lattice expansion after the ultrafast laser heating. The simulation results agree very well with experimental data obtained with femtosecond electron diffraction.

Junjie Li; Rick Clinite; Xuan Wang; Jianming Cao

2009-07-22T23:59:59.000Z

280

Simulation of transition dynamics to high confinement in fusion plasmas  

E-Print Network [OSTI]

The transition dynamics from the low (L) to the high (H) confinement mode in magnetically confined plasmas is investigated using a first-principles four-field fluid model. Numerical results are in close agreement with measurements from the Experimental Advanced Superconducting Tokamak - EAST. Particularly, the slow transition with an intermediate dithering phase is well reproduced by the numerical solutions. Additionally, the model reproduces the experimentally determined L-H transition power threshold scaling that the ion power threshold increases with increasing particle density. The results hold promise for developing predictive models of the transition, essential for understanding and optimizing future fusion power reactors.

Nielsen, A H; Madsen, J; Naulin, V; Rasmussen, J Juul; Wan, B N

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Evaluation of System Level Modeling and Simulation Tools in Support of Savannah River Site Liquid Waste Process  

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

Savannah River Site Liquid Waste Process Savannah River Site Liquid Waste Process June 2009 Monica C. Regalbuto Office of Waste Processing DOE/EM Kevin G. Brown Vanderbilt University and CRESP David W. DePaoli Oak Ridge National Laboratory Candido Pereira Argonne National Laboratory John R. Shultz Office of Waste Processing DOE/EM Sahid C. Smith Office of Waste Processing DOE/EM External Technical Review for Evaluation of System Level Modeling and Simulation Tools in Support of Savannah River Site Liquid Waste Process June 2009 ACKNOWLEDGEMENTS The Review Team thanks Ms. Sonitza Blanco, Team Lead Planning and Coordination Waste Disposition Project U.S. Department of Energy Savannah River Operations Office and Mr. Pete Hill, Liquid Waste Planning Manager for Washington Savannah River Company, for their

282

External Technical Review for Evaluation of System Level Modeling and Simulation Tools in Support of Hanford Site Liquid Waste Process  

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

Hanford Site Liquid Waste Process Hanford Site Liquid Waste Process September 2009 Monica C. Regalbuto Office of Waste Processing DOE/EM Kevin G. Brown Vanderbilt University and CRESP David W. DePaoli Oak Ridge National Laboratory Candido Pereira Argonne National Laboratory John R. Shultz Office of Waste Processing DOE/EM External Technical Review for Evaluation of System Level Modeling and Simulation Tools in Support of Hanford Site Liquid Waste Process September 2009 Acknowledgements The Review Team thanks Mr. Glyn Trenchard, Team Lead for Planning and Coordination Waste Disposition Project, U.S. Department of Energy--Office of River Protection, Mr. Paul Rutland, RPP System Planning Manager for Washington River Protection Solutions, and Mr. Ernie Lee,

283

PINO - a tool for simulating neutron spectra resulting from the 7Li(p,n) reaction  

E-Print Network [OSTI]

The 7Li(p,n) reaction in combination with a 3.7 MV Van de Graaff accelerator was routinely used at FZK to perform activation as well as time-of-flight measurements with neutrons in the keV-region. Planned new setups with much higher proton currents like SARAF and FRANZ and the availability of liquid-lithium target technology will trigger a renaissance of this method. A detailed understanding of the neutron spectrum is not only important during the planning phase of an experiment, but also during for the analysis of activation experiments. Therefore, the Monte-Carlo based program PINO (Protons In Neutrons Out) was developed, which allows the simulation of neutron spectra considering the geometry of the setup and the proton-energy distribution.

R. Reifarth; M. Heil; F. Käppeler; R. Plag

2013-10-06T23:59:59.000Z

284

Development and application of chemical tools for investigating dynamic processes in cell migration  

E-Print Network [OSTI]

Cell migration is a dynamic process essential for many fundamental physiological functions, including wound repair and the immune response. Migration relies on precisely orchestrated events that are regulated in a spatially ...

Goguen, Brenda Nicole

2011-01-01T23:59:59.000Z

285

Policy Strategies and Paths to promote Sustainable Energy Systems - The dynamic Invert Simulation Tool  

E-Print Network [OSTI]

DSM, RES-E, RES-CHP, district heating, bio- fuels, solarcorresponding E.g. missing district heating grid, in urbanHeating plus DHW) dh district heating connection is in

Stadler, Michael; Kranzl, Lukas; Huber, Claus; Haas, Reinhard; Tsioliaridou, Elena

2006-01-01T23:59:59.000Z

286

Policy Strategies and Paths to promote Sustainable Energy Systems - The dynamic Invert Simulation Tool  

E-Print Network [OSTI]

investment subsidies, feed-in tariffs, tax exemptions,ment subsidy Soft Loan Feed in tariff Building Electricityloans, subsidies or feed- in-tariffs. Rather it is a matter

Stadler, Michael; Kranzl, Lukas; Huber, Claus; Haas, Reinhard; Tsioliaridou, Elena

2006-01-01T23:59:59.000Z

287

Policy Strategies and Paths to promote Sustainable Energy Systems - The dynamic Invert Simulation Tool  

E-Print Network [OSTI]

strongly dominating the energy mix for heating in Vienna.premium) on the energy carrier mix, CO 2 reductions anddevelopment of the energy carrier mix is presented in Figure

Stadler, Michael; Kranzl, Lukas; Huber, Claus; Haas, Reinhard; Tsioliaridou, Elena

2006-01-01T23:59:59.000Z

288

Policy Strategies and Paths to promote Sustainable Energy Systems - The dynamic Invert Simulation Tool  

E-Print Network [OSTI]

promotion of the use of bio-fuels or other renewable fuelsCHP, district heating, bio- fuels, solar thermal systems,electricity and transport (bio-fuel) sector till 2020. This

Stadler, Michael; Kranzl, Lukas; Huber, Claus; Haas, Reinhard; Tsioliaridou, Elena

2006-01-01T23:59:59.000Z

289

Policy Strategies and Paths to promote Sustainable Energy Systems - The dynamic Invert Simulation Tool  

E-Print Network [OSTI]

solar thermal systems (30% for DHW systems; 40% for combined systems space heating and DHW). • Soft loans

Stadler, Michael; Kranzl, Lukas; Huber, Claus; Haas, Reinhard; Tsioliaridou, Elena

2006-01-01T23:59:59.000Z

290

Hydrogen-Bonding Structure and Dynamics of Aqueous Carbonate Species from Car?Parrinello Molecular Dynamics Simulations  

Science Journals Connector (OSTI)

A comprehensive Car?Parrinello molecular dynamics (CP-MD) study of aqueous solutions of carbonic acid (H2CO3), bicarbonate (HCO3?), carbonate (CO32?), and carbon dioxide (CO2) provides new quantitative insight into the structural and dynamic aspects of the hydrogen-bonding environments for these important aqueous species and their effects on the structure, H-bonding, and dynamical behavior of the surrounding water molecules. ... The power spectra of the carbonate species were calculated as Fourier transforms of their velocity autocorrelation functions over the 14 ps production trajectories of the CP-MD simulations. ... The first solvation shell of the anion was found to contain between five and six hydrogen bonded water mols., compared to the six to seven waters found in analogous classical studies based on empirical potentials. ...

P. Padma Kumar; Andrey G. Kalinichev; R. James Kirkpatrick

2008-12-24T23:59:59.000Z

291

Dynamic simulation of batch freezing tunnels for fish using Modelica  

Science Journals Connector (OSTI)

Fish products are frozen to preserve quality and extend shelf-life. However, freezing processes in the industry are typically very energy demanding and seldom optimized with regard to energy usage. During freezing, the operating conditions for the refrigeration cycle, as well as the driving temperature difference over the product changes significantly from start to finish. A complete transient model including a refrigeration plant, an air blast freezing tunnel and food products has been built, based on the Modelica programming language. The product model is discretized into uniform layers, described with equations for temperature dependent properties such as thermal conductivity and heat capacity. Normally, fan power represents about 25 – 30% of the total refrigeration requirement, but at the end of the freezing process, heat from the fans can represent up to 95-99% of the refrigeration load. The results from this model indicates that a 33% reduction in total power consumption, with a penalty of 14% longer freezing time is possible with better operation of the fan. In general, this model can be a useful tool for visualization of energy saving measures. It combines a product model with a refrigeration system, demonstrating the effect of process modification on both single components and overall process performance.

Harald Taxt Walnum; Trond Andresen; Kristina Widell

2011-01-01T23:59:59.000Z

292

Beam-dynamics Simulations for Channeling Radiation Electron Source  

Science Journals Connector (OSTI)

Abstract The intensity and the brilliance of the compact X-ray sources based on channeling radiation are strongly dependant on the electron beam quality. It was recently proposed to combine a field-emission electron source with channeling radiation through a diamond crystal to produce high-spectral-brilliance X-rays. There are two experiments in preparation at Fermilab to prove this technique. The beam energy in the two cases are 5-MeV and 40-MeV respectively. The field-emitted beams have emittance in the nanometer range when the microbunch is 25 ps long and the charge is about 2.5fC. RF guns operating at 1.3 GHz can produce trains of at least 2 × 105 microbunches. In this contribution we present beam-dymamics simulations of a the field-emission and subsequent accelerator up to the channeling-radiation target.

D. Mihalcea; C.A. Brau; B.K. Choi; W. Gabella; J.D. Jarvis; J.W. Lewellen; M. Mendenhall; P. Piot

2014-01-01T23:59:59.000Z

293

Impact of Resolution on Simulation of Closed Mesoscale Cellular Convection Identified by Dynamically Guided Watershed Segmentation  

SciTech Connect (OSTI)

Organized mesoscale cellular convection (MCC) is a common feature of marine stratocumulus that forms in response to a balance between mesoscale dynamics and smaller scale processes such as cloud radiative cooling and microphysics. We use the Weather Research and Forecasting model with chemistry (WRF-Chem) and fully coupled cloud-aerosol interactions to simulate marine low clouds during the VOCALS-REx campaign over the southeast Pacific. A suite of experiments with 3- and 9-km grid spacing indicates resolution-dependent behavior. The simulations with finer grid spacing have smaller liquid water paths and cloud fractions, while cloud tops are higher. The observed diurnal cycle is reasonably well simulated. To isolate organized MCC characteristics we develop a new automated method, which uses a variation of the watershed segmentation technique that combines the detection of cloud boundaries with a test for coincident vertical velocity characteristics. This ensures that the detected cloud fields are dynamically consistent for closed MCC, the most common MCC type over the VOCALS-REx region. We demonstrate that the 3-km simulation is able to reproduce the scaling between horizontal cell size and boundary layer height seen in satellite observations. However, the 9-km simulation is unable to resolve smaller circulations corresponding to shallower boundary layers, instead producing invariant MCC horizontal scale for all simulated boundary layers depths. The results imply that climate models with grid spacing of roughly 3 km or smaller may be needed to properly simulate the MCC structure in the marine stratocumulus regions.

Martini, Matus; Gustafson, William I.; Yang, Qing; Xiao, Heng

2014-11-27T23:59:59.000Z

294

A Simple Interface to Computational Fluid Dynamics Programs for Building Environment Simulations  

E-Print Network [OSTI]

. SCI can be easily integrated into new CFD programs. Introduction Advanced building design requests and pressure distributions that are crucial for thermal comfort and building structure designs. TraditionallyA Simple Interface to Computational Fluid Dynamics Programs for Building Environment Simulations

Chen, Qingyan "Yan"

295

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Window Frames  

E-Print Network [OSTI]

1 Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer Arasteh and Dragan Curcija ABSTRACT Accurately analyzing heat transfer in window frame cavities radiation heat-transfer effects.) We examine three representative complex cavity cross-section profiles

296

Effect of the sliding orientation on the tribological properties of polyethylene in molecular dynamics simulations  

E-Print Network [OSTI]

Effect of the sliding orientation on the tribological properties of polyethylene in molecular properties of polyethylene PE is investigated by using classical molecular dynamics simulations. Cross: 10.1063/1.2900884 I. INTRODUCTION Polyethylene PE is one of the most widely used poly- mers because

Sawyer, Wallace

297

Accounting for patterns of collective behavior in crowd locomotor dynamics for realistic simulations  

Science Journals Connector (OSTI)

Do people in a crowd behave like a set of isolated individuals or like a cohesive group? Studies of crowd modeling usually consider pedestrian behavior either from the point of view of an isolated individual or from that of large swarms. We introduce ... Keywords: collective behavior, crowd simulation, locomotion dynamics

Stéphane Bonneaud; Kevin Rio; Pierre Chevaillier; William H. Warren

2012-01-01T23:59:59.000Z

298

Gas Phase Reaction with FT-ICR and Molecular Dynamics Simulation of Precursor Clusters for SWNTs  

E-Print Network [OSTI]

of the random cage delayed the annealing of the cage. Number of Carbon Atoms Intensity(arbitrary) NiC38 ­ CoC38 dynamics simulations of metal-containing carbon cluster formation were performed. Metal-carbon binary clusters were generated by the laser vaporization of Ni/Co or Ni/Y loaded carbon materials used

Maruyama, Shigeo

299

Ecological Modelling 180 (2004) 135151 Simulating forest fuel and fire risk dynamics across  

E-Print Network [OSTI]

fuel module tracks fine fuel, coarse fuel and live fuel for each cell on a landscape. Fine fuel age (the oldest age cohorts) in combination with disturbance history. Live fuels, also called canopyEcological Modelling 180 (2004) 135­151 Simulating forest fuel and fire risk dynamics across

He, Hong S.

300

The robust dynamical contribution to precipitation extremes in idealized warming simulations  

E-Print Network [OSTI]

The robust dynamical contribution to precipitation extremes in idealized warming simulations across shift under climate warming on the distribution of precipitation extremes and the associated sensitivity in the frequency of the most extreme categories of the precipitation events at the poleward side of the midlatitude

Chen, Gang

Note: This page contains sample records for the topic "dynamic simulation tool" 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

RAVEN AS A TOOL FOR DYNAMIC PROBABILISTIC RISK ASSESSMENT: SOFTWARE OVERVIEW  

SciTech Connect (OSTI)

RAVEN is a software tool under development at the Idaho National Laboratory (INL) that acts as the control logic driver and post-processing tool for the newly developed Thermo-Hydraylic code RELAP- 7. The scope of this paper is to show the software structure of RAVEN and its utilization in connection with RELAP-7. A short overview of the mathematical framework behind the code is presented along with its main capabilities such as on-line controlling/monitoring and Monte-Carlo sampling. A demo of a Station Black Out PRA analysis of a simplified Pressurized Water Reactor (PWR) model is shown in order to demonstrate the Monte-Carlo and clustering capabilities.

Alfonsi Andrea; Mandelli Diego; Rabiti Cristian; Joshua Cogliati; Robert Kinoshita

2013-05-01T23:59:59.000Z

302

Molecular-dynamics simulation of compressible fluid flow in two-dimensional channels  

Science Journals Connector (OSTI)

We study compressible fluid flow in narrow two-dimensional channels using a molecular-dynamics simulation method. In the simulation area, an upstream source is maintained at constant density and temperature while a downstream reservoir is kept at vacuum. The channel is sufficiently long in the direction of the flow that the finite length has little effect on the properties of the fluid in the central region. The simulated system is represented by an efficient data structure, whose internal elements are created and manipulated dynamically in a layered fashion. Consequently the computer code is highly efficient and manifests completely linear performance in simulations of large systems. We obtain the steady-state velocity, temperature, and density distributions in the system. The velocity distribution across the channel is very nearly a quadratic function of the distance from the center of the channel and reveals velocity slip at the boundaries; the temperature distribution is only approximately a quartic function of this distance from the center to the channel. The density distribution across the channel is nonuniform. We attribute this nonuniformity to the relatively high Mach number, approximately 0.5, in the fluid flow. An equation for the density distribution based on simple compressibility arguments is proposed; its predictions agree well with the simulation results. The validity of the concept of local dynamic temperature and the variation of the temperature along the channel are discussed.

M. Sun and C. Ebner

1992-10-15T23:59:59.000Z

303

Long-time protein folding dynamics from short-time molecular dynamics simulations  

E-Print Network [OSTI]

On the simulation of protein folding by short time scaleand W. A. Eaton, The protein folding “speed limit,” Curr.and T. Head-Gordon, Protein folding by distributed computing

Chodera, J D; Swope, W C; Pitera, J W; Dill, Ken A

2006-01-01T23:59:59.000Z

304

X-AND W-BAND EPR SPECTROSCOPY COMBINED WITH MOLECULAR DYNAMICS SIMULATIONS UNRAVEL THE STRUCTURE AND STRUCTURAL  

E-Print Network [OSTI]

X- AND W-BAND EPR SPECTROSCOPY COMBINED WITH MOLECULAR DYNAMICS SIMULATIONS UNRAVEL THE STRUCTURE (EPR) spectroscopy is combined with molecular dynamics (MD) simulations to study the structure and thus the EPR spectral line shape contain direct information about the secondary and tertiary structure

Steinhoff, Heinz-Jürgen

305

Quantum walks and quantum simulation of wavepacket dynamics with twisted photons  

E-Print Network [OSTI]

The "quantum walk" has emerged recently as a paradigmatic process for the dynamic simulation of complex quantum systems, entanglement production and quantum computation. Hitherto, photonic implementations of quantum walks have mainly been based on multi-path interferometric schemes in real space. Here, we report the experimental realization of a discrete quantum walk taking place in the orbital angular momentum space of light, both for a single photon and for two simultaneous photons. In contrast to previous implementations, the whole process develops in a single light beam, with no need of interferometers; it requires optical resources scaling linearly with the number of steps; and it allows flexible control of input and output superposition states. Exploiting the latter property, we also simulated the quantum dynamics of Gaussian wavepackets, exploring the system dispersion relation in momentum space and the associated spin-orbit topological features. Our demonstration introduces a novel versatile photonic platform for quantum simulations.

Filippo Cardano; Francesco Massa; Hammam Qassim; Ebrahim Karimi; Sergei Slussarenko; Domenico Paparo; Corrado de Lisio; Fabio Sciarrino; Enrico Santamato; Robert W. Boyd; Lorenzo Marrucci

2014-07-21T23:59:59.000Z

306

Meridional circulation dynamics from 3D MHD global simulations of solar convection  

E-Print Network [OSTI]

The form of the solar meridional circulation is a very important ingredient for mean field flux transport dynamo models. Yet a shroud of mystery still surrounds this large-scale flow, given that its measurement using current helioseismic techniques is challenging. In this work we use results from 3D global simulations of solar convection to infer the dynamical behavior of the established meridional circulation. We make a direct comparison between the meridional circulation that arises in these simulations and the latest observations. Based on our results we argue that there should be an equatorward flow at the base of the convection zone at mid latitudes, below the current maximum depth helioseismic measures can probe (0.75 R). We also provide physical arguments to justify this behaviour. The simulations indicate that the meridional circulation undergoes substantial changes in morphology as the magnetic cycle unfolds. We close by discussing the importance of these dynamical changes for current methods of obse...

Passos, Dario; Miesch, Mark

2015-01-01T23:59:59.000Z

307

Single-Molecule Spectroscopic Tools for Measuring Microsecond to Millisecond Dynamics of Calmodulin  

E-Print Network [OSTI]

of interchange between conformational substates of CaM were measured demonstrating an increase in the rates of interchange between conformations in the presence of Ca2+. This supports the view that when bound to Ca2+, CaM is in a more dynamic state leading to its...

Price, E. Shane

2009-09-01T23:59:59.000Z

308

Ab-initio molecular dynamics simulation of liquid water by Quantum Monte Carlo  

E-Print Network [OSTI]

Despite liquid water is ubiquitous in chemical reactions at roots of life and climate on earth, the prediction of its properties by high-level ab initio molecular dynamics simulations still represents a formidable task for quantum chemistry. In this article we present a room temperature simulation of liquid water based on the potential energy surface obtained by a many-body wave function through quantum Monte Carlo (QMC) methods. The simulated properties are in excellent agreement with recent neutron scattering and X-ray experiments, particularly concerning the position of the oxygen-oxygen peak in the radial distribution function, at variance of previous Density Functional Theory attempts. Given the excellent performances of QMC on large scale supercomputers, this work opens new perspectives for predictive and reliable ab-initio simulations of complex chemical systems.

Zen, Andrea; Mazzola, Guglielmo; Guidoni, Leonardo; Sorella, Sandro

2014-01-01T23:59:59.000Z

309

Ab-initio molecular dynamics simulation of liquid water by Quantum Monte Carlo  

E-Print Network [OSTI]

Despite liquid water is ubiquitous in chemical reactions at roots of life and climate on earth, the prediction of its properties by high-level ab initio molecular dynamics simulations still represents a formidable task for quantum chemistry. In this article we present a room temperature simulation of liquid water based on the potential energy surface obtained by a many-body wave function through quantum Monte Carlo (QMC) methods. The simulated properties are in excellent agreement with recent neutron scattering and X-ray experiments, particularly concerning the position of the oxygen-oxygen peak in the radial distribution function, at variance of previous Density Functional Theory attempts. Given the excellent performances of QMC on large scale supercomputers, this work opens new perspectives for predictive and reliable ab-initio simulations of complex chemical systems.

Andrea Zen; Ye Luo; Guglielmo Mazzola; Leonardo Guidoni; Sandro Sorella

2014-12-09T23:59:59.000Z

310

Beam dynamics simulations and measurements at the Project X Test Facility  

SciTech Connect (OSTI)

Project X, under study at Fermilab, is a multitask high-power superconducting RF proton beam facility, aiming to provide high intensity protons for rare processes experiments and nuclear physics at low energy, and simultaneously for the production of neutrinos, as well as muon beams in the long term. A beam test facility - former known as High Intensity Neutrino Source (HINS) - is under commissioning for testing critical components of the project, e.g. dynamics and diagnostics at low beam energies, broadband beam chopping, RF power generation and distribution. In this paper we describe the layout of the test facility and present beam dynamics simulations and measurements.

Gianfelice-Wendt, E.; Scarpine, V.E.; Webber, R.C.; /Fermilab

2011-03-01T23:59:59.000Z

311

Molecular dynamics simulation of anhydrous lithium acetate: crystalline and molten phases  

Science Journals Connector (OSTI)

The results of molecular dynamics simulations of the crystalline and molten phase of anhydrous lithium acetate are presented. The potential parameters were obtained from empirical fitting to the crystalline phases of the material. The simulations were carried out for 216 molecules in an NPT ensemble using the DLPOLY program. A structural model is proposed for both the crystalline and molten phases of lithium acetate. Calculated values of the melting point, diffusion coefficient and structural parameters of lithium acetate are in reasonable agreement with experimental results.

L.S. Barreto; K.A. Mort; R.A. Jackson; O.L. Alves

2002-01-01T23:59:59.000Z

312

Dynamic customisation, validation and integration of product data models using semantic web tools  

Science Journals Connector (OSTI)

Standard product data models enable information exchange across different organisations, actors, processes and stages in the product lifecycle. These standard models need to support diverse domain-specific requirements from the multitude of disciplines involved during a product's lifecycle. Due to this diversity, challenges are to: 1) develop multidisciplinary models; 2) extend them to support new requirements over time; 3) implement the resulting gigantic information models. ISO 10303, the reference standard for PLM-related data models provides mechanisms to enable specialisation of generic product data to address some of these challenges. In this paper, we introduce the need for dynamic product data models, detail the ISO method and identify its limitations. We present enhancements to that methodology using ontologies and the SPARQL Inference Notation (SPIN) for validating product data. To conclude, we show how these ontologies can be leveraged to ease and strengthen PLM data integration through the use of Linked Data.

Sylvere Krima; Allison Barnard Feeney; Sebti Foufou

2014-01-01T23:59:59.000Z

313

Dynamic transport simulation code including plasma rotation and radial electric field  

Science Journals Connector (OSTI)

A new one-dimensional transport code named TASK/TX, which is able to describe dynamic behavior of tokamak plasmas, has been developed. It solves simultaneously a set of flux-surface averaged equations composed of Maxwell's equations, continuity equations, ... Keywords: 52.25.Fi, 52.30.-q, 52.55.Fa, 52.65.-y, Finite element method, Plasma rotation, Radial electric field, SUPG, Transport simulation

M. Honda; A. Fukuyama

2008-02-01T23:59:59.000Z

314

Detonation Initiation from Spontaneous Hotspots Formed During Cook-Off Observed in Molecular Dynamics Simulations  

Science Journals Connector (OSTI)

Detonation Initiation from Spontaneous Hotspots Formed During Cook-Off Observed in Molecular Dynamics Simulations ... New equations based on Johnson?Mehl?Avrami?Kolmogorov kinetics are proposed for describing the extent of detonated material that could provide new insight into mechanisms of critical hotspot nucleation. ... Depending on the chemical and thermal properties of the energetic material as well as the size and containment of the material during cook-off, a supersonic reaction front can form; that is, the material can detonate. ...

Yanhong Hu; Donald W. Brenner; Yunfeng Shi

2011-01-06T23:59:59.000Z

315

Ultrapdeep water blowouts: COMASim dynamic kill simulator validation and best practices recommendations  

E-Print Network [OSTI]

64 3 14 30 6 8 4 3 180 Total 26.7% 35.6% 1.7% 7.8% 16.7% 3.3% 4.4% 2.2% 1.7% 100.0% * External causes are typical; storm, military activity, ship collision, fire and earthquake. Fig. 1.10 clearly shows the most blowouts occur... 1 ULTRADEEP WATER BLOWOUTS: COMASIM DYNAMIC KILL SIMULATOR VALIDATION AND BEST PRACTICES RECOMMENDATIONS A Thesis by SAMUEL F. NOYNAERT...

Noynaert, Samuel F.

2005-02-17T23:59:59.000Z

316

A Gaussian process-based approach for handling uncertainty in vehicle dynamics simulation.  

SciTech Connect (OSTI)

Advances in vehicle modeling and simulation in recent years have led to designs that are safer, easier to handle, and less sensitive to external factors. Yet, the potential of simulation is adversely impacted by its limited ability to predict vehicle dynamics in the presence of uncertainty. A commonly occurring source of uncertainty in vehicle dynamics is the road-tire friction interaction, typically represented through a spatially distributed stochastic friction coefficient. The importance of its variation becomes apparent on roads with ice patches, where if the stochastic attributes of the friction coefficient are correctly factored into real time dynamics simulation, robust control strategies could be designed to improve transportation safety. This work concentrates on correctly accounting in the nonlinear dynamics of a car model for the inherent uncertainty in friction coefficient distribution at the road/tire interface. The outcome of this effort is the ability to quantify the effect of input uncertainty on a vehicle's trajectory and the associated escalation of risk in driving. By using a space-dependent Gaussian process, the statistical representation of the friction coefficient allows for consistent space dependence of randomness. The approach proposed allows for the incorporation of noise in the observed data and a nonzero mean for inhomogeneous distribution of the friction coefficient. Based on the statistical model considered, consistent friction coefficient sample distributions are generated over large spatial domains of interest. These samples are subsequently used to compute and characterize the statistics associated with the dynamics of a nonlinear vehicle model. The information concerning the state of the road and thus the friction coefficient is assumed available (measured) at a limited number of points by some sensing device that has a relatively homogeneous noise field (satellite picture or ground sensors, for instance). The methodology proposed can be modified to incorporate information that is sensed by each individual car as it advances along its trajectory.

Schmitt, K.; Madsen, J.; Anitescu, M.; Negrut, D.; Mathematics and Computer Science; Univ. of Wisconsin at Madison

2009-01-01T23:59:59.000Z

317

Molecular Dynamic Simulation of Sodium in 7-Pin LMFBR Bundle Under Hypothetical Accident Conditions  

SciTech Connect (OSTI)

In the frame of safety analysis of liquid metal fast breeder reactors (LMFBRs) under hypothetical Unprotected Loss of Flow (ULOF) conditions two-phase flow of sodium is simulated in a 7-pin bundle, with hexagonal lattice. Molecular dynamics, with the application of the Direct Simulation Monte Carlo (DSMC) method, and a macroscopic model describing rewetting sequences due to the flow of a sodium liquid film along the pin surfaces, are applied to simulate the coolant in the bundle. The pin surfaces and the inner surface of the hexagonal canning are treated in the Monte Carlo simulation as diffusively reflecting surfaces. Collisions of sodium molecules are computed with the 'hard-sphere' model. With respect to previous work the following improvements of the computational code were made: i) The full bundle is simulated, thus allowing for asymmetries, like a skewed power distribution, to be accounted for; ii) A pin model calculates detailed temperature distributions in the pins, so that temperature boundary conditions are computed and not imposed; iii) Post processing visualisation of computed results was developed. An out of pile sodium boiling experiment run at the Nuclear Research Center of Karlsruhe, Germany, is simulated and conclusions are drawn about the applicability of the methodology in computer codes dedicated to breeder reactors safety analysis. (authors)

Bottoni, Maurizio [University of Ferrara, Physics Department, Via Paradiso 12, I-44100 Ferrara (Italy); Bottoni, Claudio; Scanu, John [University of Pisa, Lungarno Pacinotti, 43 - 56126 Pisa (Italy)

2006-07-01T23:59:59.000Z

318

Computer simulation study of surface wave dynamics at the crystal--melt interface  

E-Print Network [OSTI]

We study, by means of computer simulations, the crystal-melt interface of three different systems: hard-spheres, Lennard Jones and the TIP4P/2005 water model. In particular, we focus on the dynamics of surface waves. We observe that the processes involved in the relaxation of surface waves are characterized by distinct time scales: a slow one related to the continuous recrystallization and melting, that is governed by capillary forces; and a fast one which we suggest to be due to a combination of processes that quickly cause small perturbations to the shape of the interface (like e. g. Rayleigh waves, subdiffusion, or attachment/detachment of particles to/from the crystal). The relaxation of surface waves becomes dominated by the slow process as the wavelength increases. Moreover, we see that the slow relaxation is not influenced by the details of the microscopic dynamics. In a time scale characteristic for the diffusion of the liquid phase, the relaxation dynamics of the crystal-melt interface of water is around one order of magnitude slower than that of Lennard Jones or hard spheres, which we ascribe to the presence of orientational degrees of freedom in the water molecule. Finally, we estimate the rate of crystal growth from our analysis of the capillary wave dynamics and compare it with previous simulation studies and with experiments for the case of water.

Jorge Benet; Luis G. MacDowell; Eduardo Sanz

2014-10-01T23:59:59.000Z

319

Defect microstructural evolution in ion irradiated metallic nanofoils: Kinetic Monte Carlo simulation versus cluster dynamics modeling and in situ transmission electron microscopy experiments  

SciTech Connect (OSTI)

Understanding materials degradation under intense irradiation is important for the development of next generation nuclear power plants. Here we demonstrate that defect microstructural evolution in molybdenum nanofoils in situ irradiated and observed on a transmission electron microscope can be reproduced with high fidelity using an object kinetic Monte Carlo (OKMC) simulation technique. Main characteristics of defect evolution predicted by OKMC, namely, defect density and size distribution as functions of foil thickness, ion fluence and flux, are in excellent agreement with those obtained from the in situ experiments and from previous continuum-based cluster dynamics modeling. The combination of advanced in situ experiments and high performance computer simulation/modeling is a unique tool to validate physical assumptions/mechanisms regarding materials response to irradiation, and to achieve the predictive power for materials stability and safety in nuclear facilities.

Xu Donghua; Wirth, Brian D. [Department of Nuclear Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States); Li Meimei [Division of Nuclear Engineering, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Kirk, Marquis A. [Division of Materials Science, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2012-09-03T23:59:59.000Z

320

The viscosity radius in dilute polymer solutions: Universal behaviour from DNA rheology and Brownian dynamics simulations  

E-Print Network [OSTI]

The swelling of the viscosity radius, $\\alpha_\\eta$, and the universal viscosity ratio, $U_{\\eta R}$, have been determined experimentally for linear DNA molecules in dilute solutions with excess salt, and numerically by Brownian dynamics simulations, as a function of the solvent quality. In the latter instance, asymptotic parameter free predictions have been obtained by extrapolating simulation data for finite chains to the long chain limit. Experiments and simulations show a universal crossover for $\\alpha_\\eta$ and $U_{\\eta R}$ from $\\theta$ to good solvents in line with earlier observations on synthetic polymer-solvent systems. The significant difference between the swelling of the dynamic viscosity radius from the observed swelling of the static radius of gyration, is shown to arise from the presence of hydrodynamic interactions in the non-draining limit. Simulated values of $\\alpha_\\eta$ and $U_{\\eta R}$ are in good agreement with experimental measurements in synthetic polymer solutions reported previously, and with the measurements in linear DNA solutions reported here.

Sharadwata Pan; D. Ahirwal; Duc At Nguyen; T. Sridhar; P. Sunthar; J. Ravi Prakash

2014-05-16T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

A molecular dynamics simulation of DNA damage induction by ionizing radiation  

E-Print Network [OSTI]

We present a multi-scale simulation of early stage of DNA damages by the indirect action of hydroxyl ($^\\bullet$OH) free radicals generated by electrons and protons. The computational method comprises of interfacing the Geant4-DNA Monte Carlo with the ReaxFF molecular dynamics software. A clustering method was employed to map the coordinates of $^\\bullet$OH-radicals extracted from the ionization track-structures onto nano-meter simulation voxels filled with DNA and water molecules. The molecular dynamics simulation provides the time evolution and chemical reactions in individual simulation voxels as well as the energy-landscape accounted for the DNA-$^\\bullet$OH chemical reaction that is essential for the first principle enumeration of hydrogen abstractions, chemical bond breaks, and DNA-lesions induced by collection of ions in clusters less than the critical dimension which is approximately 2-3 \\AA. We show that the formation of broken bonds leads to DNA base and backbone damages that collectively propagate ...

Abolfath, Ramin M; Chen, Zhe J; Nath, Ravinder

2013-01-01T23:59:59.000Z

322

Molecular simulations of the fluctuating conformational dynamics of intrinsically disordered proteins  

Science Journals Connector (OSTI)

Intrinsically disordered proteins (IDPs) do not possess well-defined three-dimensional structures in solution under physiological conditions. We develop all-atom, united-atom, and coarse-grained Langevin dynamics simulations for the IDP ?-synuclein that include geometric, attractive hydrophobic, and screened electrostatic interactions and are calibrated to the inter-residue separations measured in recent single-molecule fluorescence energy transfer (smFRET) experiments. We find that ?-synuclein is disordered, with conformational statistics that are intermediate between random walk and collapsed globule behavior. An advantage of calibrated molecular simulations over constraint methods is that physical forces act on all residues, not only on residue pairs that are monitored experimentally, and these simulations can be used to study oligomerization and aggregation of multiple ?-synuclein proteins that may precede amyloid formation.

W. Wendell Smith; Carl F. Schreck; Nabeem Hashem; Sherwin Soltani; Abhinav Nath; Elizabeth Rhoades; Corey S. O’Hern

2012-10-12T23:59:59.000Z

323

An adaptively refined phase-space element method for cosmological simulations and collisionless dynamics  

E-Print Network [OSTI]

Dark matter numerical simulations and the N-body method are essential for understanding how structure forms and evolves in the Universe. However, the discrete nature of N-body simulations can affect its accuracy when modelling collisionless systems. We introduce a new approach to simulate the gravitational evolution of cold collisionless fluids by solving the Vlasov-Poisson equations in terms of adaptively refineable "Lagrangian phase space elements". These geometrical elements are piecewise smooth maps between three-dimensional Lagrangian space and six-dimensional Eulerian phase space and approximate the continuum structure of the distribution function. They allow for dynamical adaptive splitting to follow the evolution even in regions of very strong mixing. We discuss various test problems which demonstrate the correctness and performance of our method. We show that it has several advantages compared to standard N-body algorithms by i) explicitly tracking the fine-grained distribution function, ii) naturall...

Hahn, Oliver

2015-01-01T23:59:59.000Z

324

Molecular dynamics simulation of complex molecules at interfaces: dendritic surfactants in clay and amyloid peptides near lipid bilayers  

E-Print Network [OSTI]

We apply a molecular dynamics (MD) simulation technique to complex molecules at interfaces. Partitioning of dendritic surfactants into clay gallery and Ab protein behavior near hydrated lipids are chosen for the purpose. Using a full atomistic model...

Han, Kunwoo

2009-06-02T23:59:59.000Z

325

Simulation of polar stratospheric clouds in the specified dynamics version of the whole atmosphere community climate model  

E-Print Network [OSTI]

We evaluate the simulation of polar stratospheric clouds (PSCs) in the Specified Dynamics version of the Whole Atmosphere Community Climate Model for the Antarctic winter 2005. In this model, PSCs are assumed to form ...

Wegner, T.

326

Decision Support for Green Supply Chain Operations by Integrating Dynamic Simulation and LCA Indicators: Diaper Case Study  

Science Journals Connector (OSTI)

Decision Support for Green Supply Chain Operations by Integrating Dynamic Simulation and LCA Indicators: Diaper Case Study ... Lifecycle assessment (LCA) is widely used to measure the environmental consequences assignable to a product. ... This paper proposes a framework for green supply chain management by integrating a SC dynamic simulation and LCA indicators to evaluate both the economic and environmental impacts of various SC decisions such as inventories, distribution network configuration, and ordering policy. ...

Arief Adhitya; Iskandar Halim; Rajagopalan Srinivasan

2011-10-26T23:59:59.000Z

327

The Molecular Structure of a Phosphatidylserine Bilayer Determined by Scattering and Molecular Dynamics Simulations  

SciTech Connect (OSTI)

Phosphatidylserine (PS) lipids play essential roles in biological processes, including enzyme activation and apoptosis. We report on the molecular structure and atomic scale interactions of a fluid bilayer composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylserine (POPS). A scattering density profile model, aided by molecular dynamics (MD) simulations, was developed to jointly refine different contrast small-angle neutron and X-ray scattering data, which yielded a lipid area of 62.7 A2 at 25 C. MD simulations with POPS lipid area constrained at different values were also performed using all-atom and aliphatic united-atom models. The optimal simulated bilayer was obtained using a model-free comparison approach. Examination of the simulated bilayer, which agrees best with the experimental scattering data, reveals a preferential interaction between Na+ ions and the terminal serine and phosphate moieties. Long-range inter-lipid interactions were identified, primarily between the positively charged ammonium, and the negatively charged carboxylic and phosphate oxygens. The area compressibility modulus KA of the POPS bilayer was derived by quantifying lipid area as a function of surface tension from area-constrained MD simulations. It was found that POPS bilayers possess a much larger KA than that of neutral phosphatidylcholine lipid bilayers. We propose that the unique molecular features of POPS bilayers may play an important role in certain physiological functions.

Pan, Jianjun [University of South Florida, Tampa (USF)] [University of South Florida, Tampa (USF); Cheng, Xiaolin [ORNL] [ORNL; Monticelli, Luca [Institut National de la Santé et de la Recherche Médicale (INSERM) and INTS, France] [Institut National de la Santé et de la Recherche Médicale (INSERM) and INTS, France; Heberle, Frederick A [ORNL] [ORNL; Kucerka, Norbert [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,] [Atomic Energy of Canada Limited (AECL), Canadian Neutron Beam Centre (CNBC) and Comenius University,; Tieleman, D. Peter [University of Calgary, ALberta, Canada] [University of Calgary, ALberta, Canada; Katsaras, John [ORNL] [ORNL

2014-01-01T23:59:59.000Z

328

Dynamic modelling of MSF plants for automatic control and simulation purposes: a survey  

Science Journals Connector (OSTI)

The successful development of a control system requires an appropriate definition of the control structure (i.e., selection of output, input and disturbance variables) and an efficient dynamical model on which the design, analysis and evaluation can be carried out. Thus, the confidence in the obtained results depends on the validity of the control structure and of the model used. For multistage flash (MSF) desalination processes, several dynamical models can be found in the literature. However, most of them are not suitable for analysis and control design purposes because they bring too many variables into play. The variables, which are sharing in the control system, normally constitute a reduced subset of the total variables that can be defined in the process. Moreover, a dynamical model suitable for control is simpler than the model derived from the physics of the underlying process. Hence, the selection of variables and the model building from the point of view of control design presents a compromise between the indispensable information contained in the model and the mathematical complexity proper of the design. In this paper, different models from the literature are analysed. Their advantages and drawbacks are described taking into account simulation and automatic control purposes. Moreover, a set of wished modelling facilities from the control engineer point of view is highlighted. Finally, a block-oriented library for Matlab/Simulink is presented, so that different plant configurations can be implemented as block diagram to simulate the system and to test control algorithms.

Adrian Gambler; Essameddin Badreddin

2004-01-01T23:59:59.000Z

329

Technology Transfer Webinar on November 12: High-Performance Hybrid Simulation/Measurement-Based Tools for Proactive Operator Decision-Support  

Broader source: Energy.gov [DOE]

DOE/OE and EPRI will host a technology transfer webinar on Wednesday, November 12, 2014 from noon to 2 p.m. (ET). The purpose of this open webinar is to disseminate results and outcomes of the recently completed project “High-Performance Hybrid Simulation/Measurement-Based Tools for Proactive Operator Decision-Support,” which is one of the awarded projects of the DOE Advanced Modeling Grid Research Program.

330

Numerical Simulation of Squeeze Film Dampers and Study of the Effect of Central Groove on the Dynamic Pressure Distribution  

E-Print Network [OSTI]

. The behavior of dynamic pressure profiles at different operating conditions, and the effect of a central groove on dynamic pressure profiles were also studied. Simulation results of a 3D case which is similar to the one experimentally studied by Delgado were...

Boppa, Praneetha

2012-10-19T23:59:59.000Z

331

Driving Down HB-LED Costs: Implementation of Process Simulation Tools and Temperature Control Methods of High Yield MOCVD Growth  

SciTech Connect (OSTI)

The overall objective of this multi-faceted program is to develop epitaxial growth systems that meet a goal of 75% (4X) cost reduction in the epitaxy phase of HB-LED manufacture. A 75% reduction in yielded epitaxy cost is necessary in order to achieve the cost goals for widespread penetration of HB-LEDâ??s into back-lighting units (BLU) for LCD panels and ultimately for solid-state lighting (SSL). To do this, the program will address significant improvements in overall equipment Cost of Ownership, or CoO. CoO is a model that includes all costs associated with the epitaxy portion of production. These aspects include cost of yield, capital cost, operational costs, and maintenance costs. We divide the program into three phases where later phases will incorporate the gains of prior phases. Phase one activities are enabling technologies. In collaboration with Sandia National Laboratories we develop a Fluent-compatible chemistry predictive model and a set of mid-infrared and near-ultraviolet pyrometer monitoring tools. Where previously the modeling of the reactor dynamics were studied within FLUENT alone, here, FLUENT and Chemkin are integrated into a comprehensive model of fluid dynamics and the most advanced transport equations developed for Chemkin. Specifically, the Chemkin model offered the key reaction terms for gas-phase nucleation, a key consideration in the optimization of the MOCVD process. This new predictive model is used to design new MOCVD reactors with optimized growth conditions and the newly developed pyrometers are used monitor and control the MOCVD process temperature to within 0.5°C run-to-run and within each wafer. This portion of the grant is in collaboration with partners at Sandia National Laboratories. Phase two activities are continuous improvement projects which extend the current reactor platform along the lines of improved operational efficiency, improved systems control for throughput, and carrier modifications for increased yield. Programmatically, improvements made in Phase I are applied to developments of Phase II when applicable. Phase three is the culmination of the individual tasks from both phases one and two applied to proposed production platforms. We selectively combine previously demonstrated tasks and other options to develop a high-volume production-worthy MOCVD system demonstrating >3x throughput, 1.3x capital efficiency, and 0.7x cost of ownership. In a parallel demonstration we validate the concept of an improved, larger deposition system which utilizes the predictive modeling of chemistry-based flow analysis and extensions of the improvements demonstrated on the current platforms. This validation includes the build and testing of a prototype version of the hardware and demonstration of 69% reduction in the cost of ownership. Also, in this phase we present a stand-alone project to develop a high-temperature system which improves source efficiency by 30% while concurrently increasing growth rate by 1.3x. The material quality is held to the same material quality specifications of our existing baseline processes. The merits of other line item tasks in phase three are discussed for inclusion on next-generation platforms.

William Quinn

2012-04-30T23:59:59.000Z

332

Velo: Knowledge and Tool  

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

Velo: Knowledge and Tool Integration for Collaborative Scientific Projects Carina Lansing, Kerstin Kleese van Dam 1 Scientific Project Life Cycle 2 Conceptual Modeling Simulation...

333

Canonicalization and symplectic simulation of the gyrocenter dynamics in time-independent magnetic fields  

SciTech Connect (OSTI)

The gyrocenter dynamics of charged particles in time-independent magnetic fields is a non-canonical Hamiltonian system. The canonical description of the gyrocenter has both theoretical and practical importance. We provide a general procedure of the gyrocenter canonicalization, which is expressed by the series of a small variable ? depending only on the parallel velocity u and can be expressed in a recursive manner. We prove that the truncation of the series to any given order generates a set of exact canonical coordinates for a system, whose Lagrangian approximates to that of the original gyrocenter system in the same order. If flux surfaces exist for the magnetic field, the series stops simply at the second order and an exact canonical form of the gyrocenter system is obtained. With the canonicalization schemes, the canonical symplectic simulation of gyrocenter dynamics is realized for the first time. The canonical symplectic algorithm has the advantage of good conservation properties and long-term numerical accuracy, while avoiding numerical instability. It is worth mentioning that explicitly expressing the canonical Hamiltonian in new coordinates is usually difficult and impractical. We give an iteration procedure that is easy to implement in the original coordinates associated with the coordinate transformation. This is crucial for modern large-scale simulation studies in plasma physics. The dynamics of gyrocenters in the dipole magnetic field and in the toroidal geometry are simulated using the canonical symplectic algorithm by comparison with the higher-order non symplectic Runge-Kutta scheme. The overwhelming superiorities of the symplectic method for the gyrocenter system are evidently exhibited.

Zhang, Ruili; Tang, Yifa; Zhu, Beibei [LSEC, ICMSEC, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)] [LSEC, ICMSEC, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); Liu, Jian, E-mail: jliuphy@ustc.edu.cn; Xiao, Jianyuan [Department of Modern Physics and Collaborative Innovation Center for Advanced Fusion Energy and Plasma Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China)] [Department of Modern Physics and Collaborative Innovation Center for Advanced Fusion Energy and Plasma Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Qin, Hong [Department of Modern Physics and Collaborative Innovation Center for Advanced Fusion Energy and Plasma Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China) [Department of Modern Physics and Collaborative Innovation Center for Advanced Fusion Energy and Plasma Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

2014-03-15T23:59:59.000Z

334

Numerical simulation of the stochastic dynamics of inclusions in biomembranes in presence of surface tension  

E-Print Network [OSTI]

The stochastic dynamics of inclusions in a randomly fluctuating biomembrane is simulated. These inclusions can represent the embedded proteins and the external particles arriving at a cell membrane. The energetics of the biomembrane is modelled via the Canham-Helfrich Hamiltonian. The contributions of both the bending elastic-curvature energy and the surface tension of the biomembrane are taken into account. The biomembrane is treated as a two-dimensional sheet whose height variations from a reference frame is treated as a stochastic Wiener process. The lateral diffusion parameter associated with this Wiener process coupled with the longitudinal diffusion parameter obtained from the standard Einsteinian diffusion theory completely determine the stochastic motion of the inclusions. It is shown that the presence of surface tension significantly affects the overall dynamics of the inclusions, particularly the rate of capture of the external inclusions, such as drug particles, at the site of the embedded inclusions, such as the embedded proteins.

H. Rafii-Tabar; H. R. Sepangi

2005-08-30T23:59:59.000Z

335

Quantum molecular dynamics simulation of shock-wave experiments in aluminum  

SciTech Connect (OSTI)

We present quantum molecular dynamics calculations of principal, porous, and double shock Hugoniots, release isentropes, and sound velocity behind the shock front for aluminum. A comprehensive analysis of available shock-wave data is performed; the agreement and discrepancies of simulation results with measurements are discussed. Special attention is paid to the melting region of aluminum along the principal Hugoniot; the boundaries of the melting zone are estimated using the self-diffusion coefficient. Also, we make a comparison with a high-quality multiphase equation of state for aluminum. Independent semiempirical and first-principle models are very close to each other in caloric variables (pressure, density, particle velocity, etc.) but the equation of state gives higher temperature on the principal Hugoniot and release isentropes than ab initio calculations. Thus, the quantum molecular dynamics method can be used for calibration of semiempirical equations of state in case of lack of experimental data.

Minakov, D. V.; Khishchenko, K. V.; Fortov, V. E. [Joint Institute for High Temperatures RAS, Izhorskaya 13 Bldg 2, Moscow 125412 (Russian Federation); Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudny, Moscow Region 141700 (Russian Federation); Levashov, P. R. [Joint Institute for High Temperatures RAS, Izhorskaya 13 Bldg 2, Moscow 125412 (Russian Federation); Tomsk State University, 36 Lenin Prospekt, Tomsk 634050 (Russian Federation)

2014-06-14T23:59:59.000Z

336

Induced crystallization of single-chain polyethylene on a graphite surface: Molecular dynamics simulation  

Science Journals Connector (OSTI)

Molecular dynamics (MD) simulations have been carried out on the crystallization of single-chain polyethylene (PE) which was adsorbed on a graphite (001) surface on one side and exposed to vacuum on the other at different temperatures. The MD simulation data have been analyzed to provide information about the crystallization process of polymer adsorbed on the solid substrate. The isothermal crystallization of PE proceeds in two steps: (1) adsorption and (2) orientation. The results detail the radial density distribution function, ordered parameters, local bond-orientational order parameters, and the local properties displayed in layers of the polymer parallel to the graphite and vacuum interfaces. It was also shown that the film thickness affected the critical crystallization temperature of the adsorbed polymer on the substrate surface. Furthermore, the influence of the graphite surface area on the crystallization of PE is discussed by comparing the crystallinity evolution of PE on graphite with different coverage.

Hua Yang (??); Xiao Jun Zhao (???); Miao Sun (??)

2011-07-14T23:59:59.000Z

337

Temperature-dependent mechanical properties of single-layer molybdenum disulphide: Molecular dynamics nanoindentation simulations  

SciTech Connect (OSTI)

The temperature-dependent mechanical properties of single-layer molybdenum disulphide (MoS{sub 2}) are obtained using molecular dynamics (MD) nanoindentation simulations. The Young's moduli, maximum load stress, and maximum loading strain decrease with increasing temperature from 4.2?K to 500?K. The obtained Young's moduli are in good agreement with those using our MD uniaxial tension simulations and the available experimental results. The tendency of maximum loading strain with different temperature is opposite with that of metal materials due to the short range Stillinger-Weber potentials in MoS{sub 2}. Furthermore, the indenter tip radius and fitting strain effect on the mechanical properties are also discussed.

Zhao, Junhua, E-mail: junhua.zhao@uni-weimar.de [Jiangsu Province Key Laboratory of Advanced Manufacturing Equipment and Technology of Food, Jiangnan University, 214122 Wuxi (China) [Jiangsu Province Key Laboratory of Advanced Manufacturing Equipment and Technology of Food, Jiangnan University, 214122 Wuxi (China); Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany); Jiang, Jin-Wu, E-mail: jwjiang5918@hotmail.com [Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany)] [Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany); Rabczuk, Timon, E-mail: timon.rabczuk@uni-weimar.de [Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany) [Institute of Structural Mechanics, Bauhaus-University Weimar, 99423 Weimar (Germany); School of Civil, Environmental and Architectural Engineering, Korea University, 136-701 Seoul (Korea, Republic of)

2013-12-02T23:59:59.000Z

338

Analog and digital dynamic simulations of a rigid body aircraft in straight and level flight  

E-Print Network [OSTI]

. , Texas A&M University Directed by: Dr. Balusu M. Rao A study of the dynamic response characteristics of an aircraft at low approach speeds was conducted using both a digital and an analog computer to simulate a DeHavilland "Beaver" DHC-2 in flight... to produce more sideslip and yawing motions than the rudder with analytical solutions. The problem areas of the STOL aircraft at low approach speeds as a result of a study of the DeHavilland "Beaver" were in lateral stability. The aircraft's response...

Stroman, Morris Michael

2012-06-07T23:59:59.000Z

339

Design strategy for a Chemical Looping Combustion system using process simulation and Computational Fluid Dynamics  

Science Journals Connector (OSTI)

A strategy for design and optimisation of chemical processes involving multiple fluidised bed reactors is presented through a combination of standard design calculations, process simulation and Computational Fluid Dynamics (CFD). The strategy is demonstrated in designing a Chemical Looping Combustion (CLC) process that generates 12.5 kW of heat in the air reactor. The resulting design strategy will allow for very economical investigations into various design and optimisation considerations. It also offers a platform from which to conduct virtual prototyping investigations for new process concepts, which will lead to significant economic benefits when compared with a traditional experimental process development strategy.

Schalk Cloete; Shahriar Amini

2012-01-01T23:59:59.000Z

340

Use of Aria to simulate laser weld pool dynamics for neutron generator production.  

SciTech Connect (OSTI)

This report documents the results for the FY07 ASC Integrated Codes Level 2 Milestone number 2354. The description for this milestone is, 'Demonstrate level set free surface tracking capabilities in ARIA to simulate the dynamics of the formation and time evolution of a weld pool in laser welding applications for neutron generator production'. The specialized boundary conditions and material properties for the laser welding application were implemented and verified by comparison with existing, two-dimensional applications. Analyses of stationary spot welds and traveling line welds were performed and the accuracy of the three-dimensional (3D) level set algorithm is assessed by comparison with 3D moving mesh calculations.

Noble, David R.; Notz, Patrick K.; Martinez, Mario J.; Kraynik, Andrew Michael

2007-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Cooling Energy Demand Evaluation by Meansof Regression Models Obtained From Dynamic Simulations  

E-Print Network [OSTI]

was calculated to be -8.78oC (Moscow in January) and maximum of 42.9 oC (Abu-Dhabi in August). The hourly values of outdoor air temperature and solar radiation were obtained using Trnsys (Trnsys, 2006) meteonorm files. b) Glazing surface and distribution... the ,,black-box,, function, dynamic simulations were conducted using Trnsys 16 software (Trnsys, 2005). The Trnsys building model, known as, Type 56, is compliant with general requirements of European Directive on the energy performance of buildings...

Catalina, T.; Virgone, J.

2011-01-01T23:59:59.000Z

342

Computational fluid dynamics simulation of hydrodynamics and chemical reaction in a CFB downer  

Science Journals Connector (OSTI)

Abstract A computational fluid dynamics (CFD) model for simulating the chemical reaction process in a gas–particle circulating fluidized bed (CFB) downer is introduced by combining the two-fluid model (TFM) for the gas–particle turbulent flows and the c 2 ¯ ? ? c model for the turbulent mass transfer. With the proposed model, the species concentration and solid volume fraction as well as the velocity distributions along the CFB downer are able to be predicted. In mathematical expression of the proposed model, the recently developed formulations of c 2 ¯ ? ? c is adopted to close the turbulent mass transfer equations so that the turbulent mass diffusivity can be determined without relying on empirical methods. As for the gas–solid two phase turbulent momentum transfer equations, the methodology of kg ? ?g ? kp ? ?p ? ? is used for their closures. To validate the proposed model, simulation is carried out for the catalytic ozone decomposition in a gas–solid CFB downer. The simulation results are compared with the experimental data and satisfactory agreement is found between them in both axial/radial distributions of concentration and solid volume fraction. Furthermore, the simulations reveal that the turbulent mass diffusivity varies along axial and radial directions, and the turbulent Schmidt number is not a constant throughout the CFB downer.

Wenbin Li; Kuotsung Yu; Botan Liu; Xigang Yuan

2015-01-01T23:59:59.000Z

343

Molecular dynamics simulations of damage production by thermal spikes in Ge  

SciTech Connect (OSTI)

Molecular dynamics simulation techniques are used to analyze damage production in Ge by the thermal spike process and to compare the results to those obtained for Si. As simulation results are sensitive to the choice of the inter-atomic potential, several potentials are compared in terms of material properties relevant for damage generation, and the most suitable potentials for this kind of analysis are identified. A simplified simulation scheme is used to characterize, in a controlled way, the damage generation through the local melting of regions in which energy is deposited. Our results show the outstanding role of thermal spikes in Ge, since the lower melting temperature and thermal conductivity of Ge make this process much more efficient in terms of damage generation than in Si. The study is extended to the modeling of full implant cascades, in which both collision events and thermal spikes coexist. Our simulations reveal the existence of bigger damaged or amorphous regions in Ge than in Si, which may be formed by the melting and successive quenching induced by thermal spikes. In the particular case of heavy ion implantation, defect structures in Ge are not only bigger, but they also present a larger net content in vacancies than in Si, which may act as precursors for the growth of voids and the subsequent formation of honeycomb-like structures.

Lopez, Pedro; Pelaz, Lourdes; Santos, Ivan; Marques, Luis A.; Aboy, Maria [Departamento de Electricidad y Electronica, Universidad de Valladolid, E.T.S.I. Telecomunicacion, Valladolid 47011 (Spain)

2012-02-01T23:59:59.000Z

344

Building Energy Software Tools Directory: TAS  

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

TAS TAS TAS logo Tas is an industry-leading building modelling and simulation tool. Capable of performing fast dynamic thermal simulation for the worldÂ’s largest and most complex buildings, Tas allows designers to accurately predict energy consumption, CO2 emissions, operating costs and occupant comfort. Tas is a complete solution for the thermal simulation of a building and a comprehensive tool for modelling plant and systems using itÂ’s graphical and component based analysis. Tas is a powerful design tool in the optimisation of a buildings environmental, energy and comfort performance. Tas can import gbXML, INP, and IDF files from 3rd party programs. There are also customisable report generation facilities. The Tas suite allows full automation available through visual basic. This

345

NREL: Wind Research - Offshore Design Tools and Methods  

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

Design Tools and Methods Design Tools and Methods Graphic of a modular depiction of the FAST tool, which includes aerodynamics, hydrodynamics, control and electrical system dynamics, and structural dynamics modules. NREL's CAE Tool, FAST, and its Sub-Modules Illustration of wind turbines in various environments including land-based, shallow water (0-30m), transitional depth (30-60m), and deep water floating (greater than 60m). FAST has the capability of modeling a wide range of offshore wind system configurations including shallow water, transitional depth, and floating systems. With DOE's support, NREL has developed and maintains a robust, open-source, modular computer-aided engineering (CAE) tool, known as FAST. It has state-of-the-art capabilities for full dynamic system simulation over a

346

Fully coupled time-domain simulation of dynamic positioning semi-submersible platform using dynamic surface control  

Science Journals Connector (OSTI)

A fully coupled 6-degree-of-freedom nonlinear dynamic model is presented to analyze the dynamic response of a semi-submersible platform which is equipped with the dynamic positioning...

Haizhi Liang; Luyu Li; Jinping Ou

2014-06-01T23:59:59.000Z

347

Vacancy profile in reverse osmosis membranes studied by positron annihilation lifetime measurements and molecular dynamics simulations  

Science Journals Connector (OSTI)

The positron annihilation technique using a slow positron beam can be used for the study of the vacancy profiles in typical reverse osmosis (RO) membranes. In this study, the vacancy profile in the polyamide membrane that exhibits a high permselectivity between ions and water was studied using the positron annihilation technique and molecular dynamics simulations. Ortho-positronium (o-Ps) lifetimes in the surface region of the membranes were evaluated by using a slow positron beam. The diffusion behavior of Na+ and water in the polyamides was simulated by molecular dynamics (MD) methods using the TSUBAME2 supercomputer at the Tokyo Institute of Technology and discussed with the vacancy profile probed by the o-Ps. The results suggested that the large hydration size of Na+ compared to the vacancy size in the polyamides contributes to the increased diffusivity selectivity of water/Na+ that is related to the NaCl desalination performance of the membrane. Both the hydration size of the ions and the vacancy size appeared to be significant parameters to discuss the diffusivity selectivity of water/ions in typical polyamide membranes.

A Shimazu; H Goto; T Shintani; M Hirose; R Suzuki; Y Kobayashi

2013-01-01T23:59:59.000Z

348

TIME-DEPENDENT PROPERTIES OF LIQUID WATER: A COMPARISON OF CAR-PARRINELLO AND BORN-OPPENHIEMER MOLECULAR DYNAMICS SIMULATIONS  

SciTech Connect (OSTI)

A series of 30 ps first principles molecular dynamics simulations in the microcanonical ensemble were carried out to investigate transport and vibrational properties of liquid water. To allow for sufficient sampling, the thermodynamic constraints were set to an elevated temperature of around 423 K and a density of 0.71 g/cm{sup 3} corresponding to the saturated liquid density for the Becke-Lee-Yang-Parr (BLYP) representation of water. Four simulations using the Car-Parrinello molecular dynamics (CPMD) technique with varying values of the fictitious electronic mass ({mu}) and two simulations using the Born-Oppenheimer molecular dynamics (BOMD) technique are analyzed to yield structural and dynamical information. At the selected state point, the simulations are found to exhibit non-glassy dynamics and yield consistent results for the liquid structure and the self-diffusion coefficient, although the statistical uncertainties in the latter quantity are quite large. Consequently, it can be said that the CPMD and BOMD methods produce equivalent results for these properties on the time scales reported here. However, it was found that the choice of {mu} affects the frequency spectrum of the intramolecular modes, shifting them slightly to regions of lower frequency. Using a value of {mu} = 400 a.u. results in a significant drift in the electronic kinetic energy of the system over the course of 30 ps and a downward drift in the ionic temperature. Therefore, for long trajectories at elevated temperatures, lower values of this parameter are recommended for CPMD simulations of water.

Kuo, I W; Mundy, C; McGrath, M; Siepmann, J I

2005-12-29T23:59:59.000Z

349

Dynamic simulations of geologic materials using combined FEM/DEM/SPH analysis  

SciTech Connect (OSTI)

An overview of the Lawrence Discrete Element Code (LDEC) is presented, and results from a study investigating the effect of explosive and impact loading on geologic materials using the Livermore Distinct Element Code (LDEC) are detailed. LDEC was initially developed to simulate tunnels and other structures in jointed rock masses using large numbers of polyhedral blocks. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model this class of problems, LDEC now includes implementations of Cosserat point theory and cohesive elements. This approach directly simulates the transition from continuum to discontinuum behavior, thereby allowing for dynamic fracture within a combined finite element/discrete element framework. In addition, there are many application involving geologic materials where fluid-structure interaction is important. To facilitate solution of this class of problems a Smooth Particle Hydrodynamics (SPH) capability has been incorporated into LDEC to simulate fully coupled systems involving geologic materials and a saturating fluid. We will present results from a study of a broad range of geomechanical problems that exercise the various components of LDEC in isolation and in tandem.

Morris, J P; Johnson, S M

2008-03-26T23:59:59.000Z

350

Simulation as a Tool to Develop Guidelines of Envelope Design of a Typical Office Building in Egypt  

E-Print Network [OSTI]

This paper describes the use of building performance simulation software in order to develop guidelines for designing energy-efficient office building. In Egypt energy codes for all building types are being under development. On the other hand...

Samaan, M.M.; Ahmed, A.N.; Farag, O.M.A.; El-Sayed Khalil, M.

2011-01-01T23:59:59.000Z

351

Development Plan for the Fuel Cycle Simulator  

SciTech Connect (OSTI)

The Fuel Cycle Simulator (FCS) project was initiated late in FY-10 as the activity to develop a next generation fuel cycle dynamic analysis tool for achieving the Systems Analysis Campaign 'Grand Challenge.' This challenge, as documented in the Campaign Implementation Plan, is to: 'Develop a fuel cycle simulator as part of a suite of tools to support decision-making, communication, and education, that synthesizes and visually explains the multiple attributes of potential fuel cycles.'

Brent Dixon

2011-09-01T23:59:59.000Z

352

Two-dimensional computational fluid dynamics and conduction simulations of heat transfer in window frames with internal cavities - Part 1: Cavities only  

E-Print Network [OSTI]

1980. Numerical heat transfer and fluid flow. Washington,of heat transfer by natural convection across vertical fluidFluid Dynamics and Conduction Simulations of Heat Transfer

Gustavsen, Arild; Kohler, Christian; Arasteh, Dariush; Curcija, Dragan

2003-01-01T23:59:59.000Z

353

Fast molecular-dynamics simulation for ferroelectric thin-film capacitors using a first-principles effective Hamiltonian  

Science Journals Connector (OSTI)

A newly developed fast molecular dynamics method is applied to BaTiO3 ferroelectric thin-film capacitors with short-circuited electrodes or under applied voltage. The molecular dynamics simulations based on a first-principles effective Hamiltonian clarify that dead layers (or passive layers) between ferroelectrics and electrodes markedly affect the properties of capacitors, and predict that the system is unable to hop between a uniformly polarized ferroelectric structure and a striped ferroelectric domain structure at low temperatures. Simulations of hysteresis loops of thin-film capacitors are also performed, and their dependence on film thickness, epitaxial constraints, and electrodes are discussed.

Takeshi Nishimatsu; Umesh V. Waghmare; Yoshiyuki Kawazoe; David Vanderbilt

2008-09-04T23:59:59.000Z

354

15.872 System Dynamics II, Fall 2010  

E-Print Network [OSTI]

15.872 is a continuation of 15.871 Introduction to System Dynamics. It emphasizes tools and methods needed to apply systems thinking and simulation modeling successfully in complex real-world settings. The course uses ...

Sterman, John

355

Molecular dynamics simulations of oscillatory Couette flows with slip boundary conditions  

E-Print Network [OSTI]

The effect of interfacial slip on steady-state and time-periodic flows of monatomic liquids is investigated using non-equilibrium molecular dynamics simulations. The fluid phase is confined between atomically smooth rigid walls, and the fluid flows are induced by moving one of the walls. In steady shear flows, the slip length increases almost linearly with shear rate. We found that the velocity profiles in oscillatory flows are well described by the Stokes flow solution with the slip length that depends on the local shear rate. Interestingly, the rate dependence of the slip length obtained in steady shear flows is recovered when the slip length in oscillatory flows is plotted as a function of the local shear rate magnitude. For both types of flows, the friction coefficient at the liquid-solid interface correlates well with the structure of the first fluid layer near the solid wall.

Nikolai V. Priezjev

2012-08-27T23:59:59.000Z

356

Longitudinal beam dynamics simulation in electron rings in strong rf focusing regime  

Science Journals Connector (OSTI)

Obtaining very short bunches in an electron storage ring is one of the frontiers of the accelerator physics. The strong rf focusing (SRFF) is a way to have short bunches at a given position in the ring, thanks to the principle of the bunch length modulation. Until now, the bunch length modulation has been studied only in the limit of zero current; in this paper we present the results of a simulation code suitable to study the effects of coherent synchrotron radiation and vacuum chamber wakefields on the single bunch longitudinal dynamics in the SRFF regime . The code has been applied to three different lattices that can be realized in the Frascati e+/e- collider DA?NE for a possible experiment on bunch length modulation.

Luciano Falbo; David Alesini; Mauro Migliorati

2006-09-13T23:59:59.000Z

357

The system dynamics simulation of the expansion of the Panama Canal  

Science Journals Connector (OSTI)

The expansion of the Panama Canal could be the largest project attempted by the Republic of Panama in its 100 years of existence. The objective of this simulation study is to use the Canal Expansion Project to develop and demonstrate how more precise and applied concepts that involve complex decision-making processes can be used in a large 'system of systems'. It is an attempt to explain the decision-making processes for complex systems and develop a model that will help with the political, social and economic decision-making processes that are involved in this very large project. The challenges that are involved in this research initiative include developing the parametric expressions that explain the dynamical intricacies and validation of the expansion project.

Humberto R. Alvarez A.; Dario Solis; Arnoldo R. Cano S.; Luis Rabelo; Serge Sala-Diakanda

2009-01-01T23:59:59.000Z

358

The Melting Temperature of Bulk Silicon from ab initio Molecular Dynamics Simulations  

SciTech Connect (OSTI)

We estimated a melting temperature of Tm ~ 1540 ± 90 K at zero pressure for silicon from constant enthalpy and constant pressure (NPH) Born-Oppenheimer Molecular Dynamics (BOMD) simulations of a coexisting crystalline-liquid phase. The computed Tm is below the experimental melting point of 1685 K, but it is consistent with a previously predicted first-order liquid-liquid phase transition (LLPT) at a critical point Tc ~ 1232 K and Pc ~ - 12kB [Ganesh and Widom, Phys. Rev. Lett. 102, 075701 (2009)], which is in a highly supercooled state. This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Chemical Sciences program. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

Yoo, Soohaeng; Xantheas, Sotiris S.; Zeng, Xiao Cheng

2009-10-19T23:59:59.000Z

359

Superionicity in the hydrogen storage material Li2NH: Molecular dynamics simulations  

Science Journals Connector (OSTI)

We have employed ab initio molecular dynamics simulations in an attempt to study a temperature-induced order-disorder structural phase transformation that occurs in Li2NH at about 385 K. A structural phase transition was observed by us in the temperature range 300–400 K, in good agreement with experiment. This transition is associated with a melting of the cation sublattice (Li+), giving rise to a superionic phase, which in turn is accompanied by an order-disorder transition of the N-H bond orientation. The results obtained here can contribute to a better understanding of the hydrogen storage reactions involving Li2NH and furthermore broaden its possible technological applications toward batteries and fuel cells.

C. Moysés Araújo; Andreas Blomqvist; Ralph H. Scheicher; Ping Chen; Rajeev Ahuja

2009-05-08T23:59:59.000Z

360

Solvent Electrostriction Driven Peptide Folding revealed by Quasi-Gaussian Entropy Theory and Molecular Dynamics Simulation  

SciTech Connect (OSTI)

A quantitative understanding of the complex relationship between microscopic structure and the thermodynamics driving peptide and protein folding is a major goal of biophysical chemistry. Here, we present a methodology comprising the use of an extended quasi-Gaussian entropy theory parametrized using molecular dynamics simulation that provides a complete description of the thermodynamics of peptide conformational states. The strategy is applied to analyze the conformational thermodynamics of MR121-GSGSW, a peptide well characterized in experimental studies. The results demonstrate that the extended state of the peptide possesses the lowest partial molar entropy. The origin of this entropy decrease is found to be in the increase of the density and orientational order of the hydration water molecules around the peptide, induced by the 'unfolding'. While such a reduction of the configurational entropy is usually associated with the hydrophobic effect, it is here found to be mainly due to the interaction of the solute charges with the solvent, that is, electrostriction.

Noe, F [University of Heidelberg; Daidone, Isabella [University of Heidelberg; Smith, Jeremy C [ORNL; DiNola, Alfredo [University of Rome; Amadei, Andrea [University of Rome 'Tor Vergata', Rome, Italy

2008-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Solvent Electrostriction-Driven Peptide Folding Revealed by Quasi Gaussian Entropy Theory and Molecular Dynamics Simulation  

SciTech Connect (OSTI)

A quantitative understanding of the complex relationship between microscopic structure and the thermodynamics driving peptide and protein folding is a major goal of biophysical chemistry. Here, we present a methodology comprising the use of an extended quasi-Gaussian entropy theory parametrized using molecular dynamics simulation that provides a complete description of the thermodynamics of peptide conformational states. The strategy is applied to analyze the conformational thermodynamics of MR121-GSGSW, a peptide well characterized in experimental studies. The results demonstrate that the extended state of the peptide possesses the lowest partial molar entropy. The origin of this entropy decrease is found to be in the increase of the density and orientational order of the hydration water molecules around the peptide, induced by the 'unfolding'. While such a reduction of the configurational entropy is usually associated with the hydrophobic effect, it is here found to be mainly due to the interaction of the solute charges with the solvent, that is, electrostriction.

Noe, F [University of Heidelberg; Daidone, Isabella [University of Heidelberg; Smith, Jeremy C [ORNL; DiNola, Alfredo [University of Rome; Amadei, Andrea [University of Rome 'Tor Vergata', Rome, Italy

2008-08-01T23:59:59.000Z

362

Polymer segregation under confinement: Free energy calculations and segregation dynamics simulations  

E-Print Network [OSTI]

Monte Carlo simulations are used to study the behavior of two polymers under confinement in a cylindrical tube. Each polymer is modeled as a chain of hard spheres. We measure the free energy of the system, F, as a function of the distance between the centers of mass of the polymers, lambda, and examine the effects on the free energy functions of varying the channel diameter D and length L, as well as the polymer length N and bending rigidity, kappa. For infinitely long cylinders, F is a maximum at lambda=0, and decreases with lambda until the polymers are no longer in contact. For flexible chains, the polymers overlap along the cylinder for low lambda, while above some critical value of lambda they are longitudinally compressed and non-overlapping while still in contact. We find that the free energy barrier height, scales as Delta F/k_BT~ND^{-1.93+/-0.01}. In addition, the overlap free energy scales as F/k_BT=Nf(lambda/N;D), where f is a function parameterized by D. For channels of finite L, the free energy barrier height increases with increasing confinement aspect ratio L/D at fixed volume fraction phi, and it decreases with increasing phi at fixed L/D. Increasing the polymer bending rigidity kappa monotonically reduces the overlap free energy. For strongly confined systems, F varies linearly with lambda with a slope that scales as F'(lambda)~-k_BT D^{-beta} P^{-alpha}, where beta approx 2 and alpha approx 0.37 for N=200 chains. These exponent values deviate slightly from those predicted using a simple model, possibly due to insufficiently satisfying the conditions defining the Odijk regime. Finally, we use Monte Carlo dynamics simulations to examine polymer segregation dynamics for fully flexible chains and observe segregation rates that decrease with decreasing entropic force magnitude. The polymers are not conformationally relaxed at later times during segregation.

James M. Polson; Logan G. Montgomery

2014-08-20T23:59:59.000Z

363

Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems  

E-Print Network [OSTI]

Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized on a grid, combined with competitive numerical performance and great potential for parallelization. These properties constitute a great advantage at the time of implementing and testing new physical models. Based on our experience with the Octopus code, in this article we discuss how the real-space approach has allowed for the recent development of new ideas for the simulation of electronic systems. Among these applications are approaches to calculate response properties, modeling of photoemission, optimal control of quantum systems, simulation of plasmonic systems, and the exact solution of the Schr\\"odinger equation for low-dimensionality systems.

Andrade, Xavier; De Giovannini, Umberto; Larsen, Ask Hjorth; Oliveira, Micael J T; Alberdi-Rodriguez, Joseba; Varas, Alejandro; Theophilou, Iris; Helbig, Nicole; Verstraete, Matthieu; Stella, Lorenzo; Nogueira, Fernando; Aspuru-Guzik, Alán; Castro, Alberto; Marques, Miguel A L; Rubio, Ángel

2015-01-01T23:59:59.000Z

364

Air heating of passive houses in cold climates: Investigation using detailed dynamic simulations  

Science Journals Connector (OSTI)

Abstract The passive house (PH) standard was originally defined for Central Europe and has subsequently been applied to many cold climate countries. In these conditions, the relation between this standard and the air heating (AH) is not clear while both concepts are usually associated. Furthermore, the AH provides a way to simplify the space-heating distribution system. The present contribution investigates the feasibility of the AH concept in PH along with its challenges in terms of thermal dynamics: the magnitude of the AH temperature needed, the temperature difference between rooms, the impact of internal gains, the influence of thermal losses from ventilation ducts and the AH control. This is performed using detailed dynamic simulations (TRNSYS) on a typical detached house typology. Practically, four cold climate zones are considered as well as different insulation levels and construction materials. Results show limitations related to a centralized AH as well as provide guidelines for a consistent AH design in cold climates. In addition, a simple analytical method used for the design of German PH is tested and proved accurate enough to estimate the maximal AH temperature during the heating season.

Laurent Georges; Monica Berner; Hans Martin Mathisen

2014-01-01T23:59:59.000Z

365

Molecular dynamics simulation of shock induced ejection on fused silica surface  

SciTech Connect (OSTI)

Shock response and surface ejection behaviors of fused silica are studied by using non-equilibrium molecular dynamics combining with the Tersoff potential. First, bulk structure and Hugoniot curves of fused silica are calculated and compared with experimental results. Then, the dynamical process of surface ejection behavior is simulated under different loading velocities ranging from 3.5 to 5.0?km?s, corresponding to shock wave velocities from 7.1 to 8.8?km?s. The local atomistic shear strain parameter is used to describe the local plastic deformation under conditions of shock compression or releasing. Our result shows that the shear strain is localized in the bottom area of groove under the shock compression. Surface ejection is observed when the loading velocity exceeds 4.0?km?s. Meanwhile, the temperature of the micro-jet is ?5574.7?K, which is close to experiment measurement. Several kinds of structural defects including non-bridging oxygen are found in the bulk area of the sample after ejection.

Su, Rui [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Xiang, Meizhen; Jiang, Shengli [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Chen, Jun, E-mail: jun-chen@iapcm.ac.cn [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Center for Applied Physics and Technology, Peking University, Beijing 100087 (China); Wei, Han [Research Center of Laser Fusion, Mianyang 621900 (China)

2014-05-21T23:59:59.000Z

366

Dynamic Simulation of Shipping Package Subjected to Torque Load and Sequential Impacts  

SciTech Connect (OSTI)

A numerical technique has been developed to simulate the structural responses of radioactive material packaging components requiring closure-tightening torque to the scenarios of the hypothetical accident conditions (HAC) defined in the Code of Federal Regulations Title 10 part 71 (10CFR 71). A rigorous solution to this type of problem poses a considerable mathematical challenge. Conventional methods for evaluating the residue stresses due to the torque load are either inaccurate or not applicable to dynamic analyses. In addition, the HAC events occur sequentially and the cumulative damage to the package needs to be evaluated. Commonly, individual HAC events are analyzed separately and the cumulative damage is not addressed. As a result, strict compliance of the package with the requirements specified in 10CFR 71 is usually demonstrated by physical testing. The proposed technique utilizes the combination of kinematic constraints, rigid-body motions and structural deformations to overcome some of the difficulties encountered in modeling the effect of cumulative damage in numerical solutions. The analyses demonstrating use of this technique were performed to determine the cumulative damage of torque preload, a 30-foot drop, a 30-foot dynamic crush and a 40-inch free fall onto a mild steel pipe.

Wu, T

2006-04-17T23:59:59.000Z

367

Charge constrained density functional molecular dynamics for simulation of condensed phase electron transfer reactions  

SciTech Connect (OSTI)

We present a plane-wave basis set implementation of charge constrained density functional molecular dynamics (CDFT-MD) for simulation of electron transfer reactions in condensed phase systems. Following the earlier work of Wu and Van Voorhis [Phys. Rev. A 72, 024502 (2005)], the density functional is minimized under the constraint that the charge difference between donor and acceptor is equal to a given value. The classical ion dynamics is propagated on the Born-Oppenheimer surface of the charge constrained state. We investigate the dependence of the constrained energy and of the energy gap on the definition of the charge and present expressions for the constraint forces. The method is applied to the Ru{sup 2+}-Ru{sup 3+} electron self-exchange reaction in aqueous solution. Sampling the vertical energy gap along CDFT-MD trajectories and correcting for finite size effects, a reorganization free energy of 1.6 eV is obtained. This is 0.1-0.2 eV lower than a previous estimate based on a continuum model for solvation. The smaller value for the reorganization free energy can be explained by the fact that the Ru-O distances of the divalent and trivalent Ru hexahydrates are predicted to be more similar in the electron transfer complex than for the separated aqua ions.

Oberhofer, Harald; Blumberger, Jochen [Department of Chemistry, University of Cambridge, Cambridge CB2 1EW (United Kingdom)

2009-08-14T23:59:59.000Z

368

Molecular Dynamics Simulation of Cascade-Induced Ballistic Helium Resolutioning from Bubbles in Iron  

SciTech Connect (OSTI)

Molecular dynamics simulations have been used to assess the ability of atomic displacement cascades to eject helium from small bubbles in iron. This study of the ballistic resolutioning mechanism employed a recently-developed Fe-He interatomic potential in concert with an iron potential developed by Ackland and co-workers. The primary variables examined were: irradiation temperature (100 and 600K), cascade energy (5 and 20 keV), bubble radius (0.5 and 1.0 nm), and He-to-vacancy ratio in the bubble (0.25, 0.5 and 1.0). Systematic trends were observed for each of these variables. For example, ballistic resolutioning leads to a greater number of helium atoms being displaced from larger bubbles and from bubbles that have a higher He/vacancy ratio (bubble pressure). He resolutioning was reduced at 600K relative to 100K, and for 20 keV cascades relative to 5 keV cascades. Overall, the results indicate a modest level of He removal by ballistic resolutioning. The results can be used to provide guidance in selection of a resolution parameter that can be employed in cluster dynamics models to predict the bubble size distribution that evolves under irradiation.

Stoller, Roger E [ORNL] [ORNL

2013-01-01T23:59:59.000Z

369

Pattern formation and dynamics in Rayleigh-Benard convection : numerical simulations of experimentally realistic geometries.  

SciTech Connect (OSTI)

Rayleigh-Benard convection is studied and quantitative comparisons are made, where possible, between theory and experiment by performing numerical simulations of the Boussinesq equations for a variety of experimentally realistic situations. Rectangular and cylindrical geometries of varying aspect ratios for experimental boundary conditions, including fins and spatial ramps in plate separation, are examined with particular attention paid to the role of the mean flow. A small cylindrical convection layer bounded laterally either by a rigid wall, fin, or a ramp is investigated and our results suggest that the mean flow plays an important role in the observed wavenumber. Analytical results are developed quantifying the mean flow sources, generated by amplitude gradients, and its effect on the pattern wavenumber for a large-aspect-ratio cylinder with a ramped boundary. Numerical results are found to agree well with these analytical predictions. We gain further insight into the role of mean flow in pattern dynamics by employing a novel method of quenching the mean flow numerically. Simulations of a spiral defect chaos state where the mean flow is suddenly quenched is found to remove the time dependence, increase the wavenumber and make the pattern more angular in nature.

Paul, M. R.; Chiarn, K.-H.; Cross, M. C.; Fischer, P. F.; Greenside, H. S.; Mathematics and Computer Science; California Inst. of Tech.; Duke University

2003-10-01T23:59:59.000Z

370

Molecular dynamics simulation of elevated temperature interfacial behavior between silica glass and a model crystal  

SciTech Connect (OSTI)

Elevated temperature atomistic behavior was investigated using classical molecular dynamics simulations of solid state interfaces. Initially, observations on a Lennard-Jones (LJ) crystal surface interfaced with an ideal vacuum were made. Assignment of temperatures associated with specific amounts of crystal surface disorder was possible. A temperature was observed at and above which disorder propagated through all planes of mobile atoms, making it possible to establish an approximate transition temperature for surface nucleated melting of the LJ crystal. Similar high temperature simulations were then performed on silica glass/LJ crystal interfaces at two system stress levels. No significant dependence of interface behavior on the stress states which were studied was observed. The presence of the glass surface resulted in a depression of the temperature needed for the surface most planes of crystal atoms to roughen. This allowed LJ atoms to sample and occupy sites in the glass surface. Additional data presented shows this behavior was at least partly a function of the open structure inherent in glassy oxide surfaces. {copyright} {ital 1996 American Institute of Physics.}

Webb, E.B. III; Garofalini, S.H. [Department of Ceramics, Interfacial Molecular Science Laboratory, Rutgers University, Piscataway, New Jersey 08855 (United States)] [Department of Ceramics, Interfacial Molecular Science Laboratory, Rutgers University, Piscataway, New Jersey 08855 (United States)

1996-07-01T23:59:59.000Z

371

Dynamic simulation of 10 kW Brayton cryocooler for HTS cable  

SciTech Connect (OSTI)

Dynamic simulation of a Brayton cryocooler is presented as a partial effort of a Korean governmental project to develop 1?3 km HTS cable systems at transmission level in Jeju Island. Thermodynamic design of a 10 kW Brayton cryocooler was completed, and a prototype construction is underway with a basis of steady-state operation. This study is the next step to investigate the transient behavior of cryocooler for two purposes. The first is to simulate and design the cool-down process after scheduled or unscheduled stoppage. The second is to predict the transient behavior following the variation of external conditions such as cryogenic load or outdoor temperature. The detailed specifications of key components, including plate-fin heat exchangers and cryogenic turbo-expanders are incorporated into a commercial software (Aspen HYSYS) to estimate the temporal change of temperature and flow rate over the cryocooler. An initial cool-down scenario and some examples on daily variation of cryocooler are presented and discussed, aiming at stable control schemes of a long cable system.

Chang, Ho-Myung; Park, Chan Woo [Hong Ik University, Department of Mechanical Engineering, Seoul, 121-791 (Korea, Republic of); Yang, Hyung Suk; Hwang, Si Dole [KEPCO Research Institute, Daejeon, 305-760 (Korea, Republic of)

2014-01-29T23:59:59.000Z

372

Ratcheted molecular-dynamics simulations identify efficiently the transition state of protein folding  

E-Print Network [OSTI]

The atomistic characterization of the transition state is a fundamental step to improve the understanding of the folding mechanism and the function of proteins. From a computational point of view, the identification of the conformations that build out the transition state is particularly cumbersome, mainly because of the large computational cost of generating a statistically-sound set of folding trajectories. Here we show that a biasing algorithm, based on the physics of the ratchet-and-pawl, can be used to identify efficiently the transition state. The basic idea is that the algorithmic ratchet exerts a force on the protein when it is climbing the free-energy barrier, while it is inactive when it is descending. The transition state can be identified as the point of the trajectory where the ratchet changes regime. Besides discussing this strategy in general terms, we test it within a protein model whose transition state can be studied independently by plain molecular dynamics simulations. Finally, we show its power in explicit-solvent simulations, obtaining and characterizing a set of transition--state conformations for ACBP and CI2.

Guido Tiana; Carlo Camilloni

2012-07-05T23:59:59.000Z

373

Dynamic simulation of 10 kW Brayton cryocooler for HTS cable  

Science Journals Connector (OSTI)

Dynamic simulation of a Brayton cryocooler is presented as a partial effort of a Korean governmental project to develop 1?3 km HTS cable systems at transmission level in Jeju Island. Thermodynamic design of a 10 kW Brayton cryocooler was completed and a prototype construction is underway with a basis of steady-state operation. This study is the next step to investigate the transient behavior of cryocooler for two purposes. The first is to simulate and design the cool-down process after scheduled or unscheduled stoppage. The second is to predict the transient behavior following the variation of external conditions such as cryogenic load or outdoor temperature. The detailed specifications of key components including plate-fin heat exchangers and cryogenic turbo-expanders are incorporated into a commercial software (Aspen HYSYS) to estimate the temporal change of temperature and flow rate over the cryocooler. An initial cool-down scenario and some examples on daily variation of cryocooler are presented and discussed aiming at stable control schemes of a long cable system.

2014-01-01T23:59:59.000Z

374

Path integral Monte Carlo and density functional molecular dynamics simulations of hot, dense helium  

Science Journals Connector (OSTI)

Two first-principles simulation techniques, path integral Monte Carlo (PIMC) and density functional molecular dynamics (DFT-MD), are applied to study hot, dense helium in the density-temperature range of 0.387–5.35?g?cm?3 and 500?K–1.28×108?K. One coherent equation of state is derived by combining DFT-MD data at lower temperatures with PIMC results at higher temperatures. Good agreement between both techniques is found in an intermediate-temperature range. For the highest temperatures, the PIMC results converge to the Debye-Hückel limiting law. In order to derive the entropy, a thermodynamically consistent free-energy fit is used that reproduces the internal energies and pressure derived from the first-principles simulations. The equation of state is presented in the form of a table as well as a fit and is compared with different free-energy models. Pair-correlation functions and the electronic density of states are discussed. Shock Hugoniot curves are compared with recent laser shock-wave experiments.

B. Militzer

2009-04-08T23:59:59.000Z

375

Molecular-dynamics simulations of thin polyisoprene films confined between amorphous silica substrates  

SciTech Connect (OSTI)

Constant temperature–constant pressure (NpT) molecular-dynamics computer simulations have been carried out for the united-atom model of a non-crosslinked (1,4) cis-polyisoprene (PI) melt confined between two amorphous, fully coordinated silica surfaces. The Lennard-Jones 12-6 potential was implemented to describe the polymer–silica interactions. The thickness H of the produced PI–silica film has been varied in a wide range, 1 < H/R{sub g} < 8, where R{sub g} is the individual PI chain radius of gyration measured under the imposed confinement. After a thorough equilibration, the PI film stratified structure and polymer segmental dynamics have been studied. The chain structure in the middle of the films resembles that in a corresponding bulk, but the polymer-density profile shows a pronounced ordering of the polymer segments in the vicinity of silica surfaces; this ordering disappears toward the film middles. Tremendous slowing down of the polymer segmental dynamics has been observed in the film surface layers, with the segmental relaxation more than 150 times slower as compared to that in a PI bulk. This effect increases with decreasing the polymer-film thickness. The segmental relaxation in the PI film middles shows additional relaxation process which is absent in a PI bulk. Even though there are fast relaxation processes in the film middle, its overall relaxation is slower as compared to that in a bulk sample. The interpretation of the results in terms of polymer glassy bridges has been discussed.

Guseva, D. V., E-mail: d.v.guseva@tue.nl [Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven (Netherlands); Physics Department, Chair of Polymer and Crystal Physics, M. V. Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Komarov, P. V. [Department of Theoretical Physics, Tver State University, Sadovyj per. 35, 170002 Tver, Russia and Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova st. 28, 119991 Moscow (Russian Federation)] [Department of Theoretical Physics, Tver State University, Sadovyj per. 35, 170002 Tver, Russia and Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova st. 28, 119991 Moscow (Russian Federation); Lyulin, Alexey V. [Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven (Netherlands)] [Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven (Netherlands)

2014-03-21T23:59:59.000Z

376

Development and simulation of a cylindrical cusped-field thruster and a diagnostics tool for plasma-materials interactions  

E-Print Network [OSTI]

A low power, Hall-effect type plasma thruster known as the MIT-Cylindrical Cusped- Field Thruster (MIT-CCFT) has been developed and simulated using a fully-kinetic plasma model, the Plasma Thruster particle-in-cell (PTpic) ...

Pang, Anthony

2013-01-01T23:59:59.000Z

377

Neutron scattering: a tool to detect in vivo thermal stress effects at the molecular dynamics level in micro-organisms  

Science Journals Connector (OSTI)

...Research articles 1004 30 31 68 Neutron scattering: a tool to detect in vivo...conditions was measured by neutron scattering experiments coupled with microbiological...experiments indicated that the neutron scattering method provides a promising...

2013-01-01T23:59:59.000Z

378

Non-Gaussian Fluctuation and Non-Markovian Effect in the Nuclear Fusion Process: Langevin Dynamics Emerging from Quantum Molecular Dynamics Simulations  

E-Print Network [OSTI]

Macroscopic parameters as well as precise information on the random force characterizing the Langevin type description of the nuclear fusion process are extracted from the microscopic dynamics of individual nucleons by exploiting the numerical simulation of the improved quantum molecular dynamics. It turns out that the dissipation dynamics of the relative motion between two fusing nuclei is caused by a non-Gaussian distribution of the random force. We find that the friction coefficient as well as the time correlation function of the random force takes particularly large values in a region a little bit inside of the Coulomb barrier. A clear non-Markovian effect is observed in the time correlation function of the random force. It is further shown that an emergent dynamics of the fusion process can be described by the generalized Langevin equation with memory effects by appropriately incorporating the microscopic information of individual nucleons through the random force and its time correlation function.

Wen, Kai; Li, Zhu-Xia; Wu, Xi-Zhen; Zhang, Ying-Xun; Zhou, Shan-Gui

2013-01-01T23:59:59.000Z

379

Non-Gaussian Fluctuation and Non-Markovian Effect in the Nuclear Fusion Process: Langevin Dynamics Emerging from Quantum Molecular Dynamics Simulations  

E-Print Network [OSTI]

Macroscopic parameters as well as precise information on the random force characterizing the Langevin type description of the nuclear fusion process around the Coulomb barrier are extracted from the microscopic dynamics of individual nucleons by exploiting the numerical simulation of the improved quantum molecular dynamics. It turns out that the dissipation dynamics of the relative motion between two fusing nuclei is caused by a non-Gaussian distribution of the random force. We find that the friction coefficient as well as the time correlation function of the random force takes particularly large values in a region a little bit inside of the Coulomb barrier. A clear non-Markovian effect is observed in the time correlation function of the random force. It is further shown that an emergent dynamics of the fusion process can be described by the generalized Langevin equation with memory effects by appropriately incorporating the microscopic information of individual nucleons through the random force and its time correlation function.

Kai Wen; Fumihiko Sakata; Zhu-Xia Li; Xi-Zhen Wu; Ying-Xun Zhang; Shan-Gui Zhou

2013-05-02T23:59:59.000Z

380

Dynamics  

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

Hydration Hydration Water on Rutile Studied by Backscattering Neutron Spectroscopy and Molecular Dynamics Simulation E. Mamontov,* ,† D. J. Wesolowski, ‡ L. Vlcek, § P. T. Cummings, §,| J. Rosenqvist, ‡ W. Wang, ⊥ and D. R. Cole ‡ Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6473, Chemical Sciences DiVision, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110, Department of Chemical Engineering, Vanderbilt UniVersity, NashVille, Tennessee 37235-1604, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6496, and EnVironmental Sciences DiVision, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6036 ReceiVed: December 20, 2007; ReVised Manuscript ReceiVed: June 4, 2008 The high energy resolution, coupled with the wide dynamic range, of the new backscattering

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381

AVESTAR Center: Dynamic simulation-based collaboration toward achieving opertional excellence for IGCC plants with crbon capture  

SciTech Connect (OSTI)

To address challenges in attaining operational excellence for clean energy plants, the National Energy Technology Laboratory has launched a world-class facility for Advanced Virtual Energy Simulation Training And Research (AVESTAR(TM)). The AVESTAR Center brings together state-of-the-art, real-time, high-fidelity dynamic simulators with operator training systems and 3D virtual immersive training systems into an integrated energy plant and control room environment. This paper will highlight the AVESTAR Center simulators, facilities, and comprehensive training, education, and research programs focused on the operation and control of an integrated gasification combined cycle power plant (IGCC) with carbon dioxide capture.

Zitney, Strphen E. [U.S. DOE; Liese, Eric A. [U.S. DOE; Mahapatra, Priyadarshi [URS; Turton, Richard [WVU; Bhattacharyya, Debangsu [WVU; Provost, Graham [Fossil Consulting Services

2012-01-01T23:59:59.000Z

382

Test of the Gouy-Chapman Theory for a Charged Lipid Membrane against Explicit-Solvent Molecular Dynamics Simulations  

Science Journals Connector (OSTI)

A wealth of experimental data has verified the applicability of the Gouy-Chapman (GC) theory to charged lipid membranes. Surprisingly, a validation of GC by molecular dynamics (MD) simulations has been elusive. Here, we report a test of GC against extensive MD simulations of an anionic lipid bilayer solvated by water at different concentrations of NaCl or KCl. We demonstrate that the ion distributions from the simulations agree remarkably well with GC predictions when information on the adsorption of counterions to the bilayer is incorporated.

Myunggi Yi; Hugh Nymeyer; Huan-Xiang Zhou

2008-07-18T23:59:59.000Z

383

Building Energy Software Tools Directory: NewQUICK  

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

NewQUICK NewQUICK NewQUICK logo. Thermal design and simulation tool capable of calculating loads and energy consumption. NewQuick can predict hourly air temperatures and relative humidities, which makes it a valuable tool in the passive design of building envelopes. Complete load and energy analysis of a building can further be executed in order to design an efficient air-conditioning system (HVAC). The simulation tool executes dynamic thermal calculations for realistic 'real life' temperature and load predictions. The building model integrates natural ventilation, internal load (convective and radiative), occupant load and evaporative cooling models. The simulation tool includes the modelling of external shading devices, interior mass, direct solar heat gains and ground contact surfaces.

384

Molecular Dynamics Simulation of Heat Transfer Issues of Nanotubes. > Yasuhiro Igarashi, Yuki Taniguchi, Yasushi Shibuta and Shigeo Maruyama  

E-Print Network [OSTI]

Molecular Dynamics Simulation of Heat Transfer Issues of Nanotubes. ·> Yasuhiro Igarashi, Yuki 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan Heat transfer between single-walled carbon nanotubes, which was 0.105 µm. In other words, when the length of SWNT is 0.105 µm, the radial heat transfer

Maruyama, Shigeo

385

Simulation of shock-induced melting of Ni using molecular dynamics coupled to a two-temperature model  

E-Print Network [OSTI]

Department, University of Uppsala, Box 530, SE-751 21 Uppsala, Sweden 2Lawrence Livermore National Laboratory, Livermore, California 94550, USA 3National Centre for Laser Applications, Galway, Ireland 4Department at the National Ignition Facility NIF . Molecular dynamics MD simulations have been success- fully employed

Zhigilei, Leonid V.

386

Solvation of Magnesium Dication: Molecular Dynamics Simulation and Vibrational Spectroscopic Study of Magnesium Chloride in Aqueous Solutions  

E-Print Network [OSTI]

Solvation of Magnesium Dication: Molecular Dynamics Simulation and Vibrational Spectroscopic Study of Magnesium Chloride in Aqueous Solutions Karen M. Callahan, Nadia N. Casillas-Ituarte, Martina Roeselova 26, 2010 Magnesium dication plays many significant roles in biochemistry. While it is available

387

Molecular Dynamics Simulations of End-to-End Contact Formation in Hydrocarbon Chains in Water and Aqueous Urea  

E-Print Network [OSTI]

Molecular Dynamics Simulations of End-to-End Contact Formation in Hydrocarbon Chains in Water is to probe contact formation between two ends of model hydrocarbon chains in water and 6 M aqueous urea "folding" event, namely, the formation of end-to-end contact in the linear hydrocarbon chain (HC) CH3(CH2

Thirumalai, Devarajan

388

Computational Tools to Accelerate Commercial Development  

SciTech Connect (OSTI)

The goals of the work reported are: to develop new computational tools and models to enable industry to more rapidly develop and deploy new advanced energy technologies; to demonstrate the capabilities of the CCSI Toolset on non-proprietary case studies; and to deploy the CCSI Toolset to industry. Challenges of simulating carbon capture (and other) processes include: dealing with multiple scales (particle, device, and whole process scales); integration across scales; verification, validation, and uncertainty; and decision support. The tools cover: risk analysis and decision making; validated, high-fidelity CFD; high-resolution filtered sub-models; process design and optimization tools; advanced process control and dynamics; process models; basic data sub-models; and cross-cutting integration tools.

Miller, David C.

2013-01-01T23:59:59.000Z

389

Understanding Dynamic Pricing Agents Joan Morris, Pattie Maes  

E-Print Network [OSTI]

Curve market simulator, a tool for evaluating dynamic agent pricing strategies in a simulated-world marketplaces. Towards this goal, the simulator represents sellers using different agent strategies and buyers." While models and practices exist today for setting optimal prices, such as in the travel industry

390

PINPAS: A TOOL FOR POWER ANALYSIS OF SMARTCARDS  

E-Print Network [OSTI]

;4 , J. de Vos 2 , W. Wiersma 3 Abstract This paper describes the PINPAS tool, a tool for the simulation

de Vink, Erik

391

Vehicle Technologies Office: Software Tools  

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

Software Tools Software Tools Several software programs are available, either for free or for a nominal charge, that can assist fleet managers and technology developers in assessing the potential impacts of implementing new technologies. Autonomie Autonomie is a Plug-and-Play Powertrain and Vehicle Model Architecture and Development Environment to support the rapid evaluation of new powertrain/propulsion technologies for improving fuel economy through virtual design and analysis in a math-based simulation environment. Developed in partnership with General Motors, Autonomie is an open architecture to support the rapid integration and analysis of powertrain/propulsion systems and technologies for rapid technology sorting and evaluation of fuel economy improvement under dynamic/transient testing conditions. The capability to sort technologies rapidly in a virtual design environment results in faster improvements in real-world fuel consumption by reducing the time necessary to develop and bring new technologies onto our roads.

392

Computer Simulation of Diffusion of Pb-Bi Eutectic in Liquid Sodium by Molecular Dynamics Method  

SciTech Connect (OSTI)

Lead-bismuth eutectic is a potential candidate for coolant of secondary loops of sodium-cooled fast breeder reactors (FBR). The studies on the diffusion of liquid Pb-Bi in liquid Na are carried out corresponding to the case that liquid Pb-Bi leaks to liquid Na by accident. As the diffusion processes are the results of atomic motions, molecular dynamics method has been used to study the diffusion process. The self-diffusion coefficients of pure liquid Pb and Na, and liquid Pb-Bi are calculated and compared with ones by the empirical equations. The discrepancy between them could be eliminated by changing the densities of the liquids. The diffusion of lead-bismuth in sodium is simulated based on the changed densities under which the self-diffusion coefficients of individual liquid metals are close to those by the empirical equations. The simulation results show that the diffusion process of liquid Pb-Bi in liquid Na is a heat releasing process and the density of ternary liquid Na-Pb-Bi is higher than the average value of the densities of liquid Na and liquid Pb-Bi. It is also found that the diffusion coefficients of liquid Pb-Bi in liquid Na are much higher than their self-diffusion coefficients, indicating that liquid Pb-Bi are easy and quickly to diffuse in liquid Na. However, the diffusion coefficient of liquid Na is decreased due to the existence of liquid Pb-Bi, implying that liquid Na-Pb-Bi have a higher viscosity than that of pure liquid Na. (authors)

Yingxia Qi; Minoru Takahashi [Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

2002-07-01T23:59:59.000Z

393

Dynamic modeling and simulation of hydrogen supply capacity from a metal hydride tank  

Science Journals Connector (OSTI)

Abstract The current study presents a modeling of a LaNi5 metal hydride-based hydrogen storage tank to simulate and control the dynamic processes of hydrogen discharge from a metal hydride tank in various operating conditions. The metal hydride takes a partial volume in the tank and, therefore, hydrogen discharge through the exit of the tank was driven by two factors; one factor is compressibility of pressurized gaseous hydrogen in the tank, i.e. the pressure difference between the interior and the exit of the tank makes hydrogen released. The other factor is desorption of hydrogen from the metal hydride, which is subsequently released through the tank exit. The duration of a supposed full load supply is evaluated, which depends on the initial tank pressure, the circulation water temperature, and the metal hydride volume fraction in the tank. In the high pressure regime, the duration of full load supply is increased with increasing circulation water temperature while, in the low pressure regime where the initial amount of hydrogen absorbed in the metal hydride varies sensitively with the metal hydride temperature, the duration of full load supply is increased and then decreased with increasing circulation water temperature. PID control logic was implemented in the hydrogen supply system to simulate a representative scenario of hydrogen consumption demand for a fuel cell system. The demanded hydrogen consumption rate was controlled adequately by manipulating the discharge valve of the tank at a circulation water temperature not less than a certain limit, which is increased with an increase in the tank exit pressure.

Ju-Hyeong Cho; Sang-Seok Yu; Man-Young Kim; Sang-Gyu Kang; Young-Duk Lee; Kook-Young Ahn; Hyun-Jin Ji

2013-01-01T23:59:59.000Z

394

Brittle dynamic fracture of crystalline cubic silicon carbide ,,3C-SiC... via molecular dynamics simulation  

E-Print Network [OSTI]

Brittle dynamic fracture of crystalline cubic silicon carbide ,,3C-SiC... via molecular dynamics for three low-index crack surfaces, i.e., 110 , 111 , and 100 , in crystalline cubic silicon carbide 3C Institute of Physics. DOI: 10.1063/1.2135896 I. INTRODUCTION Potential applications of silicon carbide Si

Southern California, University of

395

A.G.Ramm, Dynamical systems method (DSM) for nonlinear equations in Banach spaces, Communic. in Nonlinear Sci. and Numer. Simulation, 11,  

E-Print Network [OSTI]

A.G.Ramm, Dynamical systems method (DSM) for nonlinear equations in Banach spaces, Communic. in Nonlinear Sci. and Numer. Simulation, 11, N3, (2006), 306­310. 1 #12; Dynamical systems method (DSM, KS 66506­2602, USA ramm@math.ksu.edu http://www.math.ksu.edu/#ramm Abstract The DSM (dynamical

396

A.G.Ramm, Dynamical systems method (DSM) for nonlinear equations in Banach spaces, Communic. in Nonlinear Sci. and Numer. Simulation, 11,  

E-Print Network [OSTI]

488 A.G.Ramm, Dynamical systems method (DSM) for nonlinear equations in Banach spaces, Communic. in Nonlinear Sci. and Numer. Simulation, 11, N3, (2006), 306-310. 1 #12;Dynamical systems method (DSM, KS 66506-2602, USA ramm@math.ksu.edu http://www.math.ksu.edu/ ramm Abstract The DSM (dynamical

397

Final technical report [ACCELERATED MOLECULAR DYNAMICS SIMULATIONS OF REACTIVE HYDROCARBON SYSTEMS  

SciTech Connect (OSTI)

The research activities in this project consisted of four different sub-projects. Three different accelerated dynamics techniques (parallel replica dynamics, hyperdynamics, and temperature-accelerated dynamics) were applied to the modeling of pyrolysis of hydrocarbons. In addition, parallel replica dynamics was applied to modeling of polymerization.

Stuart, Steven J.

2014-02-25T23:59:59.000Z

398

Molecular dynamics simulation study on surface structure and surface energy of anatase  

Science Journals Connector (OSTI)

Molecular dynamics simulations were performed to investigate the relaxed structures and surface energies of perfect and pit anatase TiO2 surfaces. It is shown that the slab containing more than two unit-cell layers away from the fixed layer expresses the surface characteristics of perfect anatase TiO2 (1?0?1) and (1?0?0) surfaces well, while the slab containing more than one unit-cell layer away from the fixed layer expresses the surface characteristics of the (0?0?1) surface well. Their surface energies follow the sequence (0?0?1) ] and [0?1?0] directions, and the changes in their surface energies are less than 0.05?J?m?2, while the surface energies increase sharply with the increase in pit depth within 1?nm. Therefore, for anatase (1?0?1) surface, in order to obtain a higher surface energy, one may increase the pit sizes, particularly along the [1?0?1] direction.

Dai-Ping Song; Ming-Jun Chen; Ying-Chun Liang; Chun-Ya Wu; Zhi-Jiang Xie; Qing-Shun Bai

2010-01-01T23:59:59.000Z

399

Molecular dynamics simulations of the melting curve of NiAl alloy under pressure  

SciTech Connect (OSTI)

The melting curve of B2-NiAl alloy under pressure has been investigated using molecular dynamics technique and the embedded atom method (EAM) potential. The melting temperatures were determined with two approaches, the one-phase and the two-phase methods. The first one simulates a homogeneous melting, while the second one involves a heterogeneous melting of materials. Both approaches reduce the superheating effectively and their results are close to each other at the applied pressures. By fitting the well-known Simon equation to our melting data, we yielded the melting curves for NiAl: 1783(1 + P/9.801){sup 0.298} (one-phase approach), 1850(1 + P/12.806){sup 0.357} (two-phase approach). The good agreement of the resulting equation of states and the zero-pressure melting point (calc., 1850 ± 25 K, exp., 1911 K) with experiment proved the correctness of these results. These melting data complemented the absence of experimental high-pressure melting of NiAl. To check the transferability of this EAM potential, we have also predicted the melting curves of pure nickel and pure aluminum. Results show the calculated melting point of Nickel agrees well with experiment at zero pressure, while the melting point of aluminum is slightly higher than experiment.

Zhang, Wenjin; Peng, Yufeng [College of Physics and electronic Engineering, Henan Normal University, Xinxiang, 453007 (China)] [College of Physics and electronic Engineering, Henan Normal University, Xinxiang, 453007 (China); Liu, Zhongli, E-mail: zhongliliu@yeah.net [College of Physics and Electric Information, Luoyang Normal University, Luoyang, 471002 (China)] [College of Physics and Electric Information, Luoyang Normal University, Luoyang, 471002 (China)

2014-05-15T23:59:59.000Z

400

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

Note: This page contains sample records for the topic "dynamic simulation tool" 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

A comparative study of Lotka-Volterra and system dynamics models for simulation of technology industry dynamics  

E-Print Network [OSTI]

Scholars have developed a range of qualitative and quantitative models for generalizing the dynamics of technological innovation and identifying patterns of competition between rivals. This thesis compares two predominant ...

Ünver, Hakk? Özgür

2008-01-01T23:59:59.000Z

402

Dynamical simulation of energy dissipation in asymmetric heavy-ion induced fission of Pb200, Fr213, and Es251  

Science Journals Connector (OSTI)

The dynamical model based on the asymmetric mass division has been applied to calculate pre-scission neutron multiplicity from heavy-ion induced fusion-fission reactions. Links between the pre-scission neutron multiplicity, excitation energy, and asymmetric mass distribution are clarified based on the Monte Carlo simulation and Langevin dynamics. The pre-scission neutron multiplicity is calculated and compared with the respective experimental data over a wide range of excitation energy and nonconstant viscosity. The analysis indicates a different effect for the application of asymmetric mass division in different energy regions of such processes.

S. M. Mirfathi and M. R. Pahlavani

2008-12-29T23:59:59.000Z

403

An Occupant-Based Dynamic Simulation Tool for Predicting Residential Power Demand and Quantifying the Impact of Residential Demand Response.  

E-Print Network [OSTI]

?? With their large impact on the power system and widespread distribution, residential loads provide vast resources that if utilized correctly have the potential to… (more)

Johnson, Brandon Jeffrey

2013-01-01T23:59:59.000Z

404

ulvacsim.paper.doc 08/20/99 p. 1 of 23 Dynamic Simulation of a Multichamber CVD Cluster Tool  

E-Print Network [OSTI]

and WF6 utilization, analysis of experimental data for recipe improvement, and development and debugging with improved equipment reliability and short time-to-repair. The importance of these factors is underscored at the process, device, and circuit levels, significant attention has been devoted to equipment or reactor

Rubloff, Gary W.

405

A Robust Four-Fluid Transient Flow Simulator as an Analysis and Decision Making Tool for Dynamic Kill Operation  

E-Print Network [OSTI]

The worst scenario of drilling operation is blowout which is uncontrolled flow of formation fluid into the wellbore. Blowouts result in environmental damage with potential risk of injuries and fatalities. Although not all blowouts result in disaster...

Haghshenas, Arash

2013-04-24T23:59:59.000Z

406

A study of local and extended migration of H and defects in a-Si by molecular dynamics simulations  

SciTech Connect (OSTI)

The author reports on extensive molecular dynamics (MD) simulations on a-Si:H for up to 5 Ps using the ab initio code of Sankey and Drabold. The supercells contain about 70 atoms and only one defect in order to minimize defect-defect interaction. Simulations on supercell samples that originally contain one bond centered (BC) H in an otherwise defect free sample exhibit BC to BC diffusion as in c-Si. However, the author also observed localized motion of defects and H atoms on a very fast time scale that probably has been observed in several experiments.

Fedders, P.A. [Washington Univ., St. Louis, MO (United States). Dept. of Physics

1996-12-31T23:59:59.000Z

407

3D Computational Fluid Dynamics Simulation of Natural Coke Steam Gasification in General and Improved Fluidized Beds  

Science Journals Connector (OSTI)

The thermal characteristics of natural coke steam gasification in a fluidized bed were three-dimensionally (3D) simulated based on the computational fluid dynamics (CFD) method using Fluent code. ... However, this technology seems difficult to carry out due to its abradability, hard ignition, hot burst, and so on. ... In short, all the results in this work have a significance to provide the theoretical basis for the design, operational optimization, and scale-up of the natural coke steam gasification process. ...

Ya-li Tang; Dai-jun Liu; Yu-hong Liu; Qian Luo

2010-09-30T23:59:59.000Z

408

NREL: Wind Research - Computer-Aided Engineering Tools  

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

Computer-Aided Engineering Tools Computer-Aided Engineering Tools Illustration of an offshore wind turbine on a barge with an illustration of how the moorings would work. A simulation of a 5-MW wind turbine on an offshore semi-submersible with catenary moorings. The National Wind Technology Center (NWTC) at NREL develops advanced computer-aided engineering (CAE) tools to support the wind and water power industries with state-of-the-art design and analysis capabilities. We have developed many software tools that produce realistic models that simulate the behavior of wind and water power technologies in complex environments-storm winds, waves offshore, earthquake loading, and extreme turbulence-and model the effects of turbulent inflow, unsteady aerodynamic forces, structural dynamics, drivetrain response, control

409

A comparison of neutron scattering studies and computer simulations of polymer melts  

E-Print Network [OSTI]

A comparison of neutron scattering studies and computer simulations of polymer melts G.D. Smith a; in ®nal form 22 May 2000 Abstract Neutron scattering and computer simulations are powerful tools in particular. When neutron scattering studies and quan- titative atomistic molecular dynamics simulations

Utah, University of

410

Simulation of hydrology and population dynamics of Anopheles mosquitoes around the Koka Reservoir in Ethiopia  

E-Print Network [OSTI]

This thesis applies the HYDRology, Entomology and MAlaria Transmission Simulator (HYDREMATS) to the environment around a water resources reservoir in Ethiopia. HYDREMATS was modified to simulate the local hydrology and the ...

Endo, Noriko S.M. Massachusetts Institute of Technology

2014-01-01T23:59:59.000Z

411

The Trp Cage: Folding Kinetics and Unfolded State Topology via Molecular Dynamics Simulations  

E-Print Network [OSTI]

, ) 91 ps-1). The Folding@Home distributed computing project was used to generate an aggregate simulation

Snow, Christopher

412

Investigation of Protein Folding by Using Combined Method of Molecular Dynamics and Monte Carlo Simulations.  

E-Print Network [OSTI]

??We used the combination of molecular dynamics and Monte Carlo method to investigate protein folding problems. The environments of proteins are very big, and often… (more)

Liao, Jun-min

2006-01-01T23:59:59.000Z

413

User Guide for PV Dynamic Model Simulation Written on PSCAD Platform  

SciTech Connect (OSTI)

This document describes the dynamic photovoltaic model developed by the National Renewable Energy Laboratory and is intended as a guide for users of these models.

Muljadi, E.; Singh, M.; Gevorgian, V.

2014-11-01T23:59:59.000Z

414

Development of a ReaxFF Reactive Force Field for Ettringite and Study of its Mechanical Failure Modes from Reactive Dynamics Simulations  

Science Journals Connector (OSTI)

Development of a ReaxFF Reactive Force Field for Ettringite and Study of its Mechanical Failure Modes from Reactive Dynamics Simulations ... Ettringite is a hexacalcium aluminate trisulfate hydrate mineral that forms during Portland cement hydration. ... Here, we report on the development of this ReaxFF force field and on its validation and application using reactive molecular dynamics (RMD) simulations to characterize and understand the elastic, plastic, and failure response of ettringite at the atomic scale. ...

Lianchi Liu; Andres Jaramillo-Botero; William A. Goddard; III; Huai Sun

2012-03-13T23:59:59.000Z

415

Best practices for system dynamics model design and construction with powersim studio.  

SciTech Connect (OSTI)

This guide addresses software quality in the construction of Powersim{reg_sign} Studio 8 system dynamics simulation models. It is the result of almost ten years of experience with the Powersim suite of system dynamics modeling tools (Constructor and earlier Studio versions). It is a guide that proposes a common look and feel for the construction of Powersim Studio system dynamics models.

Malczynski, Leonard A.

2011-06-01T23:59:59.000Z

416

Combining technology roadmap and system dynamics simulation to support scenario-planning: A case of car-sharing service  

Science Journals Connector (OSTI)

Abstract Due to the volatile market environment, the use of scenario approach comes to the forefront in business strategy. As a means of scenario planning, several approaches have been proposed and conducted. However, previous research, mainly having resorted to the expert judgment for planning and evaluation, still remains conceptual and lacks a systematic link to the planning process. In response, this paper provides an integrative approach to the technology roadmap and system dynamics to support scenario planning. The proposed approach consists of three parts: scenario building, technology roadmapping, and system dynamics simulation. The first step is to construct the scenarios which are used as inputs for the scenario planning. Second, technology roadmap is developed, incorporating the scenarios built in the first step. The technology roadmap works as a strategic framework to realize the hypothetical scenarios, linking the external and hypothetical business and internal strategies. Finally, the strategic model for technology roadmap is transferred to the operational viewpoint using system dynamics. When the simulation ends, the result of each scenario is reflected to the technology roadmapping, making the multi-path technology roadmapping. As an illustrative example, three scenarios of car-sharing business are developed and analyzed.

Youngjung Geum; Sora Lee; Yongtae Park

2014-01-01T23:59:59.000Z

417

Comparison of four models simulating phosphorus dynamics in LakeVnern,Sweden Hydrology and Earth System Sciences, 8(6), 11531163 (2004) EGU  

E-Print Network [OSTI]

Comparison of four models simulating phosphorus dynamics in LakeVänern,Sweden 1153 Hydrology dynamics in Lake Vänern, Sweden Magnus Dahl1 and B. Charlotta Pers2 1 Department of Chemical Engineering, Karlstad University, SE651 88 Karlstad, Sweden 2 Swedish Meteorological and Hydrological Institute, SE601

Paris-Sud XI, Université de

418

Early maturation processes in coal. Part 2: Reactive dynamics simulations using the ReaxFF reactive force field on Morwell Brown coal structures  

E-Print Network [OSTI]

Early maturation processes in coal. Part 2: Reactive dynamics simulations using the ReaxFF reactive force field on Morwell Brown coal structures Elodie Salmon a , Adri C.T. van Duin b , François Lorant Brown coal using the ReaxFF reactive force field. We find that these reactive MD simulations

Goddard III, William A.

419

WAKE-FIELDS AND BEAM DYNAMICS SIMULATIONS C.J. Glasman & R.M. Jones; Cockcroft Institute, Daresbury, WA4 4AD, UK;  

E-Print Network [OSTI]

/m and is known as the baseline configura- tion document (BCD). However, here we investigate the electromagnetic simulated in detail using paral- lel finite difference and finite element codes [7, 8] and this data has been used as input for beam dynamics simulations, using the code LIAR [9], which tracks multi

420

Anharmonic lattice dynamics of Ag2O studied by inelastic neutron scattering and first-principles molecular dynamics simulations  

SciTech Connect (OSTI)

Inelastic neutron scattering measurements on silver oxide (Ag2O) with the cuprite structure were performed at temperatures from 40 to 400 K, and Fourier transform far-infrared spectra were measured from 100 to 300 K. The measured phonon densities of states and the infrared spectra showed unusually large energy shifts with temperature, and large linewidth broadenings. First principles molecular dynamics (MD) calculations were performed at various temperatures, successfully accounting for the negative thermal expansion (NTE) and local dynamics. Using the Fourier-transformed velocity autocorrelation method, the MD calculations reproduced the large anharmonic effects of Ag2O, and were in excellent agreement with the neutron scattering data. The quasiharmonic approximation (QHA) was less successful in accounting for much of the phonon behavior. The QHA could account for some of the NTE below 250 K, although not at higher temperatures. Strong anharmonic effects were found for both phonons and for the NTE. The lifetime broadenings of Ag2O were explained by anharmonic perturbation theory, which showed rich interactions between the Ag-dominated modes and the O-dominated modes in both up- and down-conversion processes.

Lan, Tian [California Institute of Technology, Pasadena] [California Institute of Technology, Pasadena; Li, Chen [ORNL] [ORNL; Niedziela, Jennifer L [ORNL] [ORNL; Smith, Hillary [California Institute of Technology, Pasadena] [California Institute of Technology, Pasadena; Abernathy, Douglas L [ORNL] [ORNL; Rossman, George [California Institute of Technology, Pasadena] [California Institute of Technology, Pasadena; Fultz, B. [California Institute of Technology, Pasadena] [California Institute of Technology, Pasadena

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Large scale test simulations using the Virtual Environment for Test Optimization (VETO)  

SciTech Connect (OSTI)

The Virtual Environment for Test Optimization (VETO) is a set of simulation tools under development at Sandia to enable test engineers to do computer simulations of tests. The tool set utilizes analysis codes and test information to optimize design parameters and to provide an accurate model of the test environment which aides in the maximization of test performance, training, and safety. Previous VETO effort has included the development of two structural dynamics simulation modules that provide design and optimization tools for modal and vibration testing. These modules have allowed test engineers to model and simulate complex laboratory testing, to evaluate dynamic response behavior, and to investigate system testability. Further development of the VETO tool set will address the accurate modeling of large scale field test environments at Sandia. These field test environments provide weapon system certification capabilities and have different simulation requirements than those of laboratory testing.

Klenke, S.E.; Heffelfinger, S.R.; Bell, H.J.; Shierling, C.L.

1997-10-01T23:59:59.000Z

422

A new shared-memory programming paradigm for molecular dynamics simulations on the Intel Paragon  

SciTech Connect (OSTI)

This report describes the use of shared memory emulation with DOLIB (Distributed Object Library) to simplify parallel programming on the Intel Paragon. A molecular dynamics application is used as an example to illustrate the use of the DOLIB shared memory library. SOTON-PAR, a parallel molecular dynamics code with explicit message-passing using a Lennard-Jones 6-12 potential, is rewritten using DOLIB primitives. The resulting code has no explicit message primitives and resembles a serial code. The new code can perform dynamic load balancing and achieves better performance than the original parallel code with explicit message-passing.

D`Azevedo, E.F.; Romine, C.H.

1994-12-01T23:59:59.000Z

423

Computational Fluid Dynamics Simulations of Raw Gas Composition from a Black Liquor Gasifier—Comparison with Experiments  

Science Journals Connector (OSTI)

Computational Fluid Dynamics Simulations of Raw Gas Composition from a Black Liquor Gasifier—Comparison with Experiments ... The black liquor spray was represented by 1003 discrete particles having a fitted Rosin Rammler distribution of power 2 and a characteristic size of 200 ?m. ... Additional PFR calculations were performed using different inlet gas compositions with similar results (not presented here), i.e. the Jones and Lindstedt model showed a significantly higher reformation rate of methane than GRI-Mech at gasification conditions in the medium temperature range (1150 < T < 1500 K). ...

Per Carlsson; Kristiina Iisa; Rikard Gebart

2011-07-05T23:59:59.000Z

424

Comparison of the Properties of Xenon, Methane, and Carbon Dioxide Hydrates from Equilibrium and Nonequilibrium Molecular Dynamics Simulations  

Science Journals Connector (OSTI)

Comparison of the Properties of Xenon, Methane, and Carbon Dioxide Hydrates from Equilibrium and Nonequilibrium Molecular Dynamics Simulations† ... The VACFs of all three guests in the small cages oscillate between positive and negative values with the oscillation being damped out with increasing time. ... The oscillations are damped much more strongly for CO2 hydrate than for the Xe or methane hydrates, indicating that the coupling between the rattling motions of the encaged guest molecules and the vibrational motions of the host lattice is strongest for CO2 hydrate. ...

H. Jiang; K. D. Jordan

2009-11-11T23:59:59.000Z

425

Building Energy Software Tools Directory: Tools by Country - Sweden  

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

Sweden Sweden 1 B C D E H I P S U V Tool Applications Free Recently Updated 1D-HAM heat, air, moisture transport, walls Software has been updated. BV2 annual energy use, durational diagram Software has been updated. CELLAR cellar, heat loss, design rules DAVID-32 Thermal bridges, temperatures, heat flows, computer program, freeware Free software. Software has been updated. DEROB-LTH energy performance, heating, cooling, thermal comfort, design Software has been updated. EED Earth energy, boreholes, ground heat storage, ground source heat pump system (GSHP) HEAT2 heat transfer, 2D, dynamic, simulation Software has been updated. HEAT3 heat transfer, three-dimensional heat conduction, transient heat flow, steady-state heat flow Software has been updated.

426

Cooling energy demand evaluation by means of regression models obtained from dynamic simulations  

E-Print Network [OSTI]

of energy and CO2 emitter in the EU and is the major energy consumer of the EU's total final energy consumption and CO2 emissions. Buildings account for 40­45% of energy consumption in Europe and China (and estimation of the energy consumption is very difficult. So, we need precise and easy to use support tools

Paris-Sud XI, Université de

427

Analysis and simulation of dynamic response behavior of Scots pine trees to wind loading  

Science Journals Connector (OSTI)

This paper presents an empirical approach for the decomposition, simulation, and reconstruction of wind-induced stem displacement of plantation-grown Scots ... tree motion patterns in response to non-destructive

Dirk Schindler; Hannes Fugmann; Helmut Mayer

2013-11-01T23:59:59.000Z

428

Development of dynamic models of reactive distillation columns for simulation and determination of control  

E-Print Network [OSTI]

variables were simulated. The data generated by the step responses was used for fitting transfer functions between the manipulated and the controlled variables. RGA analysis was performed to find the optimal pairing for controller design. Feedback...

Chakrabarty, Arnab

2005-02-17T23:59:59.000Z

429

Computational Fluid Dynamics (CFD) simulations of dilute fluid-particle flows in aerosol concentrators  

E-Print Network [OSTI]

's turbulent dispersion model. A detailed literature survey revealed the inherent technical deficiencies in the model, even for particle dispersion. Based on the results of this study, it was determined that while the code can be used for simulating aerosol...

Hari, Sridhar

2005-02-17T23:59:59.000Z

430

Rheological response and dynamics of the amphiphilic diamond phase from kinetic lattice–Boltzmann simulations  

Science Journals Connector (OSTI)

...diamond phase from kinetic lattice-Boltzmann simulations R.S. Saksena...are performed using a kinetic lattice-Boltzmann method. Lyotropic liquid crystals...studied previously using our lattice-Boltzmann (LB) approach (Gonzalez-Segredo...

2009-01-01T23:59:59.000Z

431

PIC–MCC Simulations of Capacitive High-Frequency Discharge Dynamics with Nanoparticles  

Science Journals Connector (OSTI)

A new combined particle-in-cell Monte Carlo collision (PIC–MCC) approach is discussed for accurate and fast simulation of a radio-frequency (rf) discharge at a low gas pressure and high plasma density. Test calcu...

Irina V. Schweigert

2010-01-01T23:59:59.000Z

432

An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem  

E-Print Network [OSTI]

In this thesis, a novel approach is presented for blade loss simulation of an aircraft gas turbine rotor mounted on rolling element bearings with squeeze film dampers, seal rub and enclosed in a flexible housing. The modal truncation augmentation...

Parthasarathy, Nikhil Kaushik

2004-09-30T23:59:59.000Z

433

FAST STATIC AND DYNAMIC GRID LEVEL THERMAL SIMULATION CONSIDERING TEMPERATURE DEPENDENT THERMAL CONDUCTIVITY OF SILICON  

E-Print Network [OSTI]

heat diffusion equation has been conventionally handled by grid-grids and an approximate delta function simulating a point heatgrid size of 64×64. To obtain transient thermal mask an impulse heat

Ziabari, Amirkoushyar

2012-01-01T23:59:59.000Z

434

Improved methods and measures for computing dynamic program slices in stochastic simulations  

Science Journals Connector (OSTI)

Stochastic simulations frequently exhibit behaviors that are difficult to recreate and analyze, owing largely to the stochastics themselves, and consequent program dependency chains that can defy human reasoning capabilities. We present a novel approach ...

Ross Gore; Paul F. Reynolds, Jr.

2010-12-01T23:59:59.000Z

435

Direct dynamics simulation of dioxetane formation and decomposition via the singlet ·O–O–CH2–CH2 · biradical: Non-RRKM dynamics  

SciTech Connect (OSTI)

Electronic structure calculations and direct chemical dynamics simulations are used to study the formation and decomposition of dioxetane on its ground state singlet potential energy surface. The stationary points for 1O2 + C2H4, the singlet {center_dot}O-O-CH2-CH2{center_dot} biradical, the transition state (TS) connecting this biradical with dioxetane, and the two transition states and gauche {center_dot}O-CH2-CH2-O{center_dot} biradical connecting dioxetane with the formaldehyde product molecules are investigated at different levels of electronic structure theory including UB3LYP, UMP2, MRMP2, and CASSCF and a range of basis sets. The UB3LYP/6-31G* method was found to give representative energies for the reactive system and was used as a model for the simulations. UB3LYP/6-31G* direct dynamics trajectories were initiated at the TS connecting the {center_dot}O-O-CH2-CH2{center_dot} biradical and dioxetane by sampling the TS's vibrational energy levels, and rotational and reaction coordinate energies, with Boltzmann distributions at 300, 1000, and 1500 K. This corresponds to the transition state theory model for trajectories that pass the TS. The trajectories were directed randomly towards both the biradical and dioxetane. A small fraction of the trajectories directed towards the biradical recrossed the TS and formed dioxetane. The remainder formed 1O2 + C2H4 and of these {approx} 40% went directly from the TS to 1O2 + C2H4 without getting trapped and forming an intermediate in the {center_dot}O-O- CH2-CH2{center_dot} biradical potential energy minimum, a non-statistical result. The dioxetane molecules which are formed dissociate to two formaldehyde molecules with a rate constant two orders of magnitude smaller than that predicted by Rice-Ramsperger-Kassel-Marcus theory. The reaction dynamics from dioxetane to the formaldehyde molecules do not follow the intrinsic reaction coordinate or involve trapping in the gauche {center_dot}O-CH2-CH2-O{center_dot} biradical potential energy minimum. Important non-statistical dynamics are exhibited for this reactive system.

Sun, Rui; Park, Kyoyeon; De Jong, Wibe A.; Lischka, Hans; Windus, Theresa L.; Hase, William L.

2012-07-28T23:59:59.000Z

436

Planning Tool for Strategic Evaluation of Facility Plans - 13570  

SciTech Connect (OSTI)

Savannah River National Laboratory (SRNL) has developed a strategic planning tool for the evaluation of the utilization of its unique resources for processing and research and development of nuclear materials. The Planning Tool is a strategic level tool for assessing multiple missions that could be conducted utilizing the SRNL facilities and showcasing the plan. Traditional approaches using standard scheduling tools and laying out a strategy on paper tended to be labor intensive and offered either a limited or cluttered view for visualizing and communicating results. A tool that can assess the process throughput, duration, and utilization of the facility was needed. SRNL teamed with Newport News Shipbuilding (NNS), a division of Huntington Ingalls Industries, to create the next generation Planning Tool. The goal of this collaboration was to create a simulation based tool that allows for quick evaluation of strategies with respect to new or changing missions, and clearly communicates results to the decision makers. This tool has been built upon a mature modeling and simulation software previously developed by NNS. The Planning Tool provides a forum for capturing dependencies, constraints, activity flows, and variable factors. It is also a platform for quickly evaluating multiple mission scenarios, dynamically adding/updating scenarios, generating multiple views for evaluating/communicating results, and understanding where there are areas of risks and opportunities with respect to capacity. The Planning Tool that has been developed is useful in that it presents a clear visual plan for the missions at the Savannah River Site (SRS). It not only assists in communicating the plans to SRS corporate management, but also allows the area stakeholders a visual look at the future plans for SRS. The design of this tool makes it easily deployable to other facility and mission planning endeavors. (authors)

Magoulas, Virginia; Cercy, Michael [Savannah River National Laboratory, Savannah River Site, Aiken, SC 29808 (United States)] [Savannah River National Laboratory, Savannah River Site, Aiken, SC 29808 (United States); Hall, Irin [Newport News Shipbuilding, 4101 Washington Ave., Newport News, VA 23607 (United States)] [Newport News Shipbuilding, 4101 Washington Ave., Newport News, VA 23607 (United States)

2013-07-01T23:59:59.000Z

437

A Parallel Tree code for large Nbody simulation: dynamic load balance and data distribution on CRAY T3D system  

E-Print Network [OSTI]

N-body algorithms for long-range unscreened interactions like gravity belong to a class of highly irregular problems whose optimal solution is a challenging task for present-day massively parallel computers. In this paper we describe a strategy for optimal memory and work distribution which we have applied to our parallel implementation of the Barnes & Hut (1986) recursive tree scheme on a Cray T3D using the CRAFT programming environment. We have performed a series of tests to find an " optimal data distribution " in the T3D memory, and to identify a strategy for the " Dynamic Load Balance " in order to obtain good performances when running large simulations (more than 10 million particles). The results of tests show that the step duration depends on two main factors: the data locality and the T3D network contention. Increasing data locality we are able to minimize the step duration if the closest bodies (direct interaction) tend to be located in the same PE local memory (contiguous block subdivison, high granularity), whereas the tree properties have a fine grain distribution. In a very large simulation, due to network contention, an unbalanced load arises. To remedy this we have devised an automatic work redistribution mechanism which provided a good Dynamic Load Balance at the price of an insignificant overhead.

U. Becciani; R. Ansaloni; V. Antonuccio-Delogu; G. Erbacci; M. Gambera; A. Pagliaro; -

1997-09-02T23:59:59.000Z

438

Dynamic modeling and simulation of a solar-assisted multi-effect distillation plant  

Science Journals Connector (OSTI)

Abstract This paper presents a dynamic model of a solar-assisted multi-effect distillation (MED) plant, carrying on with the previous work “Dynamic modeling and performance of the first cell of a multi-effect distillation plant” (de la Calle et al., 2014). The dynamic model has been designed according to the experience with an experimental solar thermal desalination system erected at CIEMAT-Plataforma Solar de Almería (PSA). The mathematical formulation based on physical principles describes the main heat and mass transfer phenomena in this kind of facilities. The model was implemented using the equation-based object-oriented Modelica modeling language. Based on a modular and hierarchical modeling, different specific-phenomenon submodels have been developed. They have been interconnected between them, thus making a three level deep hierarchy. All the submodels have been calibrated and validated with experimental data. The numerical predictions show a good agreement with measured data.

Alberto de la Calle; Javier Bonilla; Lidia Roca; Patricia Palenzuela

2015-01-01T23:59:59.000Z

439

Adapting SAFT-? perturbation theory to site-based molecular dynamics simulation. I. Homogeneous fluids  

SciTech Connect (OSTI)

In this work, we aim to develop a version of the Statistical Associating Fluid Theory (SAFT)-? equation of state (EOS) that is compatible with united-atom force fields, rather than experimental data. We rely on the accuracy of the force fields to provide the relation to experimental data. Although, our objective is a transferable theory of interfacial properties for soft and fused heteronuclear chains, we first clarify the details of the SAFT-? approach in terms of site-based simulations for homogeneous fluids. We show that a direct comparison of Helmholtz free energy to molecular simulation, in the framework of a third order Weeks-Chandler-Andersen perturbation theory, leads to an EOS that takes force field parameters as input and reproduces simulation results for Vapor-Liquid Equilibria (VLE) calculations. For example, saturated liquid density and vapor pressure of n-alkanes ranging from methane to dodecane deviate from those of the Transferable Potential for Phase Equilibria (TraPPE) force field by about 0.8% and 4%, respectively. Similar agreement between simulation and theory is obtained for critical properties and second virial coefficient. The EOS also reproduces simulation data of mixtures with about 5% deviation in bubble point pressure. Extension to inhomogeneous systems and united-atom site types beyond those used in description of n-alkanes will be addressed in succeeding papers.

Ghobadi, Ahmadreza F.; Elliott, J. Richard, E-mail: elliot1@uakron.edu [Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, Ohio 44325 (United States)

2013-12-21T23:59:59.000Z

440

Enterprise integration: A tool`s perspective  

SciTech Connect (OSTI)

The advent of sophisticated automation equipment and computer hardware and software is changing the way manufacturing is carried out. To compete in the global marketplace, manufacturing companies must integrate these new technologies into their factories. In addition, they must integrate the planning, control, and data management methodologies needed to make effective use of these technologies. This paper provides an overview of recent approaches to achieving this enterprise integration. It then describes, using simulation as a particular example, a new tool`s perspective of enterprise integration.

Polito, J. [Sandia National Labs., Albuquerque, NM (United States); Jones, A. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Grant, H. [National Science Foundation, Washington, DC (United States)

1993-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Fully 3D Multiple Beam Dynamics Processes Simulation for the Fermilab Tevatron  

SciTech Connect (OSTI)

The Fermilab Tevatron has been, until 2010, the premier high-energy physics collider in the world. The data collected over the last decade by high-energy physics experiments running at the Tevatron have been analyzed to make important measurements in fundamental areas such as B meson masses and flavor oscillation, searches for the Higgs boson, and supersymmetry. Collecting these data at the limits of detectability has required the Tevatron to operate reliably at high beam intensities to maximize the number of collisions to analyze. This impressive achievement has been assisted by the use of HPC resources and software provided through the SciDAC program. This paper describes the enhancements to the BeamBeam3d code to realistically simulate the Tevatron, the validation of these simulations, and the improvement in equipment reliability and personal safety achieved with the aid of simulations.

Stern, E.; Amundson, J.; Spentzouris, P; Valishev, A.; /Fermilab

2010-06-01T23:59:59.000Z

442

Computational fluid dynamic simulations of chemical looping fuel reactors utilizing gaseous fuels  

SciTech Connect (OSTI)

A computational fluid dynamic(CFD) model for the fuel reactor of chemical looping combustion technology has been developed,withspecialfocusonaccuratelyrepresentingtheheterogeneous chemicalreactions.Acontinuumtwo-fluidmodelwasusedtodescribeboththegasandsolidphases. Detailedsub-modelstoaccountforfluid–particleandparticle–particleinteractionforceswerealso incorporated.Twoexperimentalcaseswereanalyzedinthisstudy(Son andKim,2006; Mattisonetal., 2001). SimulationswerecarriedouttotestthecapabilityoftheCFDmodeltocapturechangesinoutletgas concentrationswithchangesinnumberofparameterssuchassuperficialvelocity,metaloxide concentration,reactortemperature,etc.Fortheexperimentsof Mattissonetal.(2001), detailedtime varyingoutletconcentrationvalueswerecompared,anditwasfoundthatCFDsimulationsprovideda reasonablematchwiththisdata.

Mahalatkar, K.; Kuhlman, J.; Huckaby, E.D.; O'Brien, T.

2011-01-01T23:59:59.000Z

443

July 26 NuFACT Target Meeting 1 Simulation of Dynamic Interaction of the Neutrino Factory  

E-Print Network [OSTI]

: Following the Successful Completion of the E951 and MERIT Experiments regarding Hg Jet Stability and BeamFACT Target Meeting 10 #12;July 26 NuFACT Target Meeting 11 #12;July 26 NuFACT Target Meeting 12 Bubble Dynamics and Hg Jet/Pool #12;July 26 NuFACT Target Meeting 13 Local pressure outside formed bubble can

McDonald, Kirk

444

Computational fluid dynamics simulation of the air/suppressant flow in an uncluttered F18 engine nacelle  

SciTech Connect (OSTI)

For the purposes of designing improved Halon-alternative fire suppression strategies for aircraft applications, Computational Fluid Dynamics (CFD) simulations of the air flow, suppressant transport, and air-suppressant mixing within an uncluttered F18 engine nacelle were performed. The release of inert gases from a Solid Propellant Gas Generator (SPGG) was analyzed at two different injection locations in order to understand the effect of injection position on the flow patterns and the mixing of air and suppression agent. An uncluttered engine nacelle was simulated to provide insight into the global flow features as well as to promote comparisons with previous nacelle fire tests and recent water tunnel tests which included little or no clutter. Oxygen concentration levels, fuel/air residence times that would exist if a small fuel leak were present, velocity contours, and streamline patterns are presented inside the engine nacelle. The numerical results show the influence of the gent release location on regions of potential flame extinction due to oxygen inerting and high flame strain. The occurrence of inflow through the exhaust ducts on the aft end of the nacelle is also predicted. As expected, the predicted oxygen concentration levels were consistently higher than the measured levels since a fire was not modeled in this analysis. Despite differences in the conditions of these simulations and the experiments, good agreement was obtained between the CFD predictions and the experimental measurements.

Lopez, A.R.; Gritzo, L.A.; Hassan, B.

1997-06-01T23:59:59.000Z

445

Computational Tools for Accelerating Carbon Capture Process Development  

SciTech Connect (OSTI)

The goals of the work reported are: to develop new computational tools and models to enable industry to more rapidly develop and deploy new advanced energy technologies; to demonstrate the capabilities of the CCSI Toolset on non-proprietary case studies; and to deploy the CCSI Toolset to industry. Challenges of simulating carbon capture (and other) processes include: dealing with multiple scales (particle, device, and whole process scales); integration across scales; verification, validation, and uncertainty; and decision support. The tools cover: risk analysis and decision making; validated, high-fidelity CFD; high-resolution filtered sub-models; process design and optimization tools; advanced process control and dynamics; process models; basic data sub-models; and cross-cutting integration tools.

Miller, David

2013-01-01T23:59:59.000Z

446

Energy conservation measures in an institutional building by dynamic simulation using designbuilder  

Science Journals Connector (OSTI)

In this study, various energy conservation measures (ECMs) on heating, ventilating and air conditioning (HVAC) and lighting systems for a 4-storied building in subtropical (hot and humid climate) Central Queensland, Australia are evaluated using the ... Keywords: designbuilder, energy conservation measures, energy efficient lighting and day light control, energy simulation, hot-humid climate, variable air volume system

M. M. Rahman; M. G. Rasul; M. M. K. Khan

2008-02-01T23:59:59.000Z

447

Simulation of U-5 prototype undulator effects on the beam dynamics  

SciTech Connect (OSTI)

The APS prototype undulator U-5 has been installed at NSLS VUV ring. Its effects on the beam behaviour have been simulated with tracking codes TEAPOT and RACETRACK. The tune shift, the distortion of betatron function, the chromaticity, the transverse coupling, and some of the amplitude-dependent effects on the VUV ring have been compared and are presented in this paper.

Qian, Y.L.; Turner, L.R.

1992-04-06T23:59:59.000Z

448

Particle simulation of collision dynamics for ion beam injection into a rarefied gas  

SciTech Connect (OSTI)

This study details a comparison of ion beam simulations with experimental data from a simplified plasma test cell in order to study and validate numerical models and environments representative of electric propulsion devices and their plumes. The simulations employ a combination of the direct simulation Monte Carlo and particle-in-cell methods representing xenon ions and atoms as macroparticles. An anisotropic collision model is implemented for momentum exchange and charge exchange interactions between atoms and ions in order to validate the post-collision scattering behaviors of dominant collision mechanisms. Cases are simulated in which the environment is either collisionless or non-electrostatic in order to prove that the collision models are the dominant source of low- and high-angle particle scattering and current collection within this environment. Additionally, isotropic cases are run in order to show the importance of anisotropy in these collision models. An analysis of beam divergence leads to better characterization of the ion beam, a parameter that requires careful analysis. Finally, suggestions based on numerical results are made to help guide the experimental design in order to better characterize the ion environment.

Giuliano, Paul N.; Boyd, Iain D. [Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2013-03-15T23:59:59.000Z

449

Sustainability analysis of complex dynamic systems using embodied energy flows: The eco-bond graphs modeling and simulation framework  

Science Journals Connector (OSTI)

Abstract This article presents a general methodology for modeling complex dynamic systems focusing on sustainability properties that emerge from tracking energy flows. We adopt the embodied energy (emergy) concept that traces all energy transformations required for running a process. Thus, energy at any process within a system is studied in terms of all the energy previously invested to support it (up to the primary sources) and therefore sustainability can be analyzed structurally. These ideas were implemented in the bond graph framework, a modeling paradigm where physical variables are explicitly checked for adherence to energy conservation principles. The results are a novel Ecological Bond Graphs (EcoBG) modeling paradigm and the new EcoBondLib library, a set of practical ready-to-use graphical models based on EcoBG principles and developed under the Modelica model encoding standard. EcoBG represents general systems in a three-faceted fashion, describing dynamics at their mass, energy, and emergy facets. EcoBG offers a scalable graphical formalism for the description of emergy dynamic equations, resolving some mathematical difficulties inherited from the original formulation of the equations. The core elements of EcoBG offer a soundly organized mathematical skeleton upon which new custom variables and indexes can be built to extend the modeling power. This can be done safely, without compromising the correctness of the core energy balance calculations. As an example we show how to implement a custom sustainability index at local submodels, for detecting unsustainable phases that are not automatically discovered when using the emergy technique alone. The fact that we implemented EcoBondLib relying on the Modelica technology opens up powerful possibilities for studying sustainability of systems with interactions between natural and industrial processes. Modelica counts on a vast and reusable knowledge base of industrial-strength models and tools in engineering applications, developed by the Modelica community throughout decades.

Rodrigo D. Castro; François E. Cellier; Andreas Fischlin

2014-01-01T23:59:59.000Z

450

FT-ICR Reaction Experiments and Molecular Dynamics Simulations of Precursor Clusters for  

E-Print Network [OSTI]

. J. D, 9, 1-4, 385 (1999). 30 40 50 60 70 Number of Carbon Atoms Intensity(arbitrary) Noise (a carbon sample. 520 530 540 43 44 45 Number of Carbon Atoms Intensity(arbitrary) NiC38 ­ CoC38 ­ NiC38(NO mechanism of single walled carbon nanotubes is investigated through experimental and molecular dynamics

Maruyama, Shigeo

451

Cisplatin Binding to DNA Oligomers from Hybrid Car-Parrinello/Molecular Dynamics Simulations  

Science Journals Connector (OSTI)

The first-principles calculations are carried out with the Car-Parrinello approach,52 which has proven to reliably describe structure, dynamics, and electronic properties of platinum?nucleotide complexes in the solid state53 as well as in water solution. ... There are more than three waters in the first solvation shell of AM1. ... The predictive power of our computational setup was investigated by constructing a structural model of platinated DNA. ...

Katrin Spiegel; Ursula Rothlisberger; Paolo Carloni

2004-01-29T23:59:59.000Z

452

Predictive Simulation and Design of Materials by Quasicontinuum and Accelerated Dynamics Methods  

SciTech Connect (OSTI)

This project developed the hyper-QC multiscale method to make possible the computation of previously inaccessible space and time scales for materials with thermally activated defects. The hyper-QC method combines the spatial coarse-graining feature of a finite temperature extension of the quasicontinuum (QC) method (aka “hot-QC”) with the accelerated dynamics feature of hyperdynamics. The hyper-QC method was developed, optimized, and tested from a rigorous mathematical foundation.

Luskin, Mitchell [University of Minnesota; James, Richard; Tadmor, Ellad

2014-03-30T23:59:59.000Z

453

Dynamic simulation of the thermal and electrical behavior of a thermionic converter coupled to a solar concentrator  

SciTech Connect (OSTI)

A mathematical simulation for the dynamic thermal and electrical behavior of a thermionic converter coupled to a solar concentrator, is presented. The thermionic device is a Cesium-filled thermionic diode operating in the ignited mode. The emitter of the device is made of polycrystalline Rhenium and the collector of the device of Molybdenum. The solar concentrator is a parabolic dish. The designed emitter and collector temperatures are 1,850 K and 928 K, respectively. However, due to changes in ambient conditions, the collector efficiency varies and so does the system efficiency. This fact makes it necessary to evaluate the design of the system not just for one hour with constant conditions but also for a whole operating day. The paper presents plots for the emitter and collector thermionic device temperatures and power and voltage for a constant resistance load as a function of time.

Perez, G. [CUAP-UAP, Puebla (Mexico). Centro de Investigaciones en Dispositivos Semiconductores; Estrada, C.A.; Cervantes, J.G. [UNAM, Temixco, Morelos (Mexico). Solar Energy Research Lab.

1995-12-31T23:59:59.000Z

454

Interaction of Polar and Nonpolar Organic Pollutants with Soil Organic Matter: Sorption Experiments and Molecular Dynamics Simulation  

E-Print Network [OSTI]

The fate of organic pollutants in the environment is influenced by several factors including the type and strength of their interactions with soil components especially SOM. However, a molecular level answer to the question How organic pollutants interact with SOM? is lacking. In order to explore mechanisms of this interaction, we have developed a new SOM model followed by carrying out molecular dynamics (MD) simulations in parallel with sorption experiments. The new SOM model comprises free SOM functional groups (carboxylic acid and naphthalene) as well as SOM cavities (with two different sizes), representing the soil voids, containing the same SOM functional groups. To examine the effect of the hydrophobicity on the interaction, the organic pollutants hexachlorobenzene (HCB, non-polar) and sulfanilamide (SAA, polar) were considered. The experimental and the theoretical outcomes explored four major points regarding sorption of SAA and HCB on soil. 1. The interaction depends on the SOM chemical composition mo...

Ahmed, Ashour A; Aziz, Saadullah G; Hilal, Rifaat H; Elroby, Shaaban A; Al-Youbi, Abdulrahman O; Leinweber, Peter; Kühn, Oliver

2014-01-01T23:59:59.000Z

455

Local Depolarization in Hydrophobic and Hydrophilic Ionic Liquids/Water Mixtures: Car–Parrinello and Classical Molecular Dynamics Simulation  

Science Journals Connector (OSTI)

Local Depolarization in Hydrophobic and Hydrophilic Ionic Liquids/Water Mixtures: Car–Parrinello and Classical Molecular Dynamics Simulation ... Their analysis of the molecular electrostatic properties compared with the previous work on smaller number of ion pairs per unit cell shows that the immediate liquid environment predominantly affects the molecular electric dipole moments, whereas the bulk contributions appear to be minor. ... The ion-pair/water interaction energy (Einter), which is defined as the difference between the energy of the ion pair and water system (EIL-W) and the sum of the energies of the single ion pair (EIL) and water (EW), can be calculated by:(1)Each complex and corresponding water and anion were optimized for structure and energy at the B3LYP/6-311++G(d,p) level of theory by the above computational procedure. ...

Mohammad Hadi Ghatee; Amin Reza Zolghadr

2013-01-08T23:59:59.000Z

456

Car–Parrinello Molecular Dynamics Simulations of CaCl2 Aqueous Solutions  

Science Journals Connector (OSTI)

(24, 25) Such ab initio molecular orbital calculations, performed at the restricted Hartree–Fock (HF) and second-order M?ller–Plesset perturbation (MP2) levels of theory and followed by natural energy decomposition analysis, emphasized the importance of polarization effects in the binding energies of M2+(H2O)n clusters. ... It shows a maximum at 3.35 D, due to the electron polarization caused by the strong electric field of the ion. ... Solution Structure of Energy Stored System I: Aqua-B(OH)4–: A DFT, Car–Parrinello Molecular Dynamics, and Raman Study ...

Teodora Todorova; Philippe H. Hünenberger; Jürg Hutter

2008-04-15T23:59:59.000Z

457

Tools & Technologies  

Broader source: Energy.gov [DOE]

We provide leadership for transforming workforce development through the power of technology. It develops corporate educational technology policy and enables the use of learning tools and...

458

Hall-effect Controlled Gas Dynamics in Protoplanetary Disks: II. Full 3D Simulations toward the Outer Disk  

E-Print Network [OSTI]

We perform 3D stratified shearing-box MHD simulations on the gas dynamics of protoplanetary disks threaded by net vertical magnetic field Bz. All three non-ideal MHD effects, Ohmic resistivity, the Hall effect and ambipolar diffusion are included in a self-consistent manner based on equilibrium chemistry. We focus on regions toward outer disk radii, from 5-60AU, where Ohmic resistivity tends to become negligible, ambipolar diffusion dominates over an extended region across disk height, and the Hall effect largely controls the dynamics near the disk midplane. We find that around R=5AU, the system launches a laminar/weakly turbulent magnetocentrifugal wind when the net vertical field Bz is not too weak, as expected. Moreover, the wind is able to achieve and maintain a configuration with reflection symmetry at disk midplane. The case with anti-aligned field polarity (Omega. Bz<0) is more susceptible to the MRI when Bz drops, leading to an outflow oscillating in radial directions and very inefficient angular m...

Bai, Xue-Ning

2014-01-01T23:59:59.000Z

459

Thermal simulation of buildings with double-skin façades  

Science Journals Connector (OSTI)

Highly glazed commercial buildings with double-skin façades may overheat during summertime due to a coincidence of high outside temperatures, solar gains and internal heat gains. To optimize thermal comfort and minimize cooling loads, the thermal behaviour of this type of building, therefore, requires careful investigation at the design stage. However, complex physical phenomena—notably optical, thermodynamic and fluid dynamic processes—are involved and as yet, no single simulation tool is able to handle all these processes while remaining an efficient design tool. This paper presents a method based on the coupling of three different types of simulation models that is economical in terms of computing time, and thereby, suitable for design purposes. These models are: spectral optical model, computational fluid dynamics model and building energy simulation model. Various tools are available at each modelling level. The method is demonstrated on a commercial building with double-skin façades and additionally, night-time ventilation.

H. Manz; Th. Frank

2005-01-01T23:59:59.000Z

460

Molecular Dynamics Simulations of the Nucleation of Water: Determining the Sticking Probability and Formation Energy of a Cluster  

E-Print Network [OSTI]

We performed molecular dynamics (MD) simulations of the nucleation of water vapor in order to test nucleation theories. Simulations were performed for a wide range of supersaturation ratios (S = 3-25) and water temperatures (Tw=300-390K). We obtained the nucleation rates and the formation free energies of a subcritical cluster from the cluster size distribution. The classical nucleation theory (CNT) and the modified classical nucleation theory (MCNT) overestimate the nucleation rates in all cases. The semi-phenomenological (SP) model, which corrects the MCNT prediction using the second virial coefficient of a vapor, reproduces the formation free energy of a cluster with the size < 20 to within 10 % and the nucleation rate and cluster size distributions to within one order of magnitude. The sticking probability of the vapor molecules to the clusters was also determined from the growth rates of the clusters. The sticking probability rapidly increases with the supersaturation ratio S, which is similar to the Lennard-Jones system.

Kyoko K. Tanaka; Akio Kawano; Hidekazu Tanaka

2014-02-26T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic simulation tool" 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

Computer simulation study of collective dynamics in the glass former Ca(NO3)2·4H2O  

Science Journals Connector (OSTI)

Time correlation functions of current fluctuations were calculated by molecular dynamics (MD) simulations in order to investigate sound waves of high wavevectors in the glass-forming liquid Ca(NO3)2·4H2O. Dispersion curves ?(k) were obtained for longitudinal (LA) and transverse acoustic (TA) modes and also for longitudinal optic (LO) modes. Spectra of LA modes calculated by MD simulations were modeled by a viscoelastic model within the memory function framework. The viscoelastic model is used to rationalize the change of slope taking place at k ? 0.3 Å?1 in the ?(k) curve of acoustic modes. For still larger wavevectors mixing of acoustic and optic modes is observed. Partial time correlation functions of longitudinal mass currents were calculated separately for the ions and the water molecules. The wavevector dependence of excitation energies of the corresponding partial LA modes indicates the coexistence of a relatively stiff subsystem made of cations and anions and a softer subsystem made of water molecules.

Mauro C. C. Ribeiro

2012-01-01T23:59:59.000Z

462

Lithium Ion Transport Mechanism in Ternary Polymer Electrolyte-Ionic Liquid Mixtures - A Molecular Dynamics Simulation Study  

E-Print Network [OSTI]

The lithium transport mechanism in ternary polymer electrolytes, consisting of PEO/LiTFSI and various fractions of the ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide, are investigated by means of MD simulations. This is motivated by recent experimental findings [Passerini et al., Electrochim. Acta 2012, 86, 330-338], which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO/LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observations, we employ an analytical, Rouse-based cation transport model [Maitra at al., PRL 2007, 98, 227802], which has originally been devised for conventional polymer electrolytes. This model describes the cation transport via three different mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium ions are coordinated by PEO chains, thus ruling out a transport mechanism enhanced by the presence of ionic-liquid molecules. Rather, the plasticizing effect of the ionic liquid contributes to the increased lithium mobility by enhancing the dynamics of the PEO chains and consequently also the motion of the attached ions. Additional focus is laid on the prediction of lithium diffusion coefficients from the simulation data for various chain lengths and the comparison with experimental data, thus demonstrating the broad applicability of our approach.

Diddo Diddens; Andreas Heuer

2012-11-14T23:59:59.000Z

463

New Modeling Tool Analyzes Floating Platform Concepts for Offshore Wind Turbines (Fact Sheet)  

SciTech Connect (OSTI)

Researchers at the National Renewable Energy Laboratory (NREL) developed a new complex modeling and analysis tool capable of analyzing floating platform concepts for offshore wind turbines. The new modeling tool combines the computational methodologies used to analyze land-based wind turbines with the comprehensive hydrodynamic computer programs developed for offshore oil and gas industries. This new coupled dynamic simulation tool will enable the development of cost-effective offshore technologies capable of harvesting the rich offshore wind resources at water depths that cannot be reached using the current technology.

Not Available

2011-02-01T23:59:59.000Z

464

Diffusion of the Cu monomer and dimer on Ag(111): Molecular dynamics simulations and density functional theory calculations  

Science Journals Connector (OSTI)

We present results of molecular dynamics (MD) simulations and density functional theory (DFT) calculations of the diffusion of Cu adatom and dimer on Ag(111). We have used potentials generated by the embedded-atom method for the MD simulations and pseudopotentials derived from the projected-augmented-wave method for the DFT calculations. The MD simulations (at three different temperatures: 300, 500, and 700 K) show that the diffusivity has an Arrhenius behavior. The effective energy barriers obtained from the Arrhenius plots are in excellent agreement with those extracted from scanning tunneling microscopy experiments. While the diffusion barrier for Cu monomers on Ag(111) is higher than that reported (both in experiment and theory) for Cu(111), the reverse holds for dimers [which, for Cu(111), has so far only been theoretically assessed]. In comparing our MD result with those for Cu islets on Cu(111), we conclude that the higher barriers for Cu monomers on Ag(111) results from the comparatively large Ag-Ag bond length, whereas for Cu dimers on Ag(111) the diffusivity is taken over and boosted by the competition in optimization of the Cu-Cu dimer bond and the five nearest-neighbor Cu-Ag bonds. Our DFT calculations confirm the relatively large barriers for the Cu monomer on Ag(111)—69 and 75 meV—compared to those on Cu(111) and hint a rationale for them. In the case of the Cu dimer, the relatively long Ag-Ag bond length makes available a diffusion route whose highest relevant energy barrier is only 72 meV and which is not favorable on Cu(111). This process, together with another involving an energy barrier of 83 meV, establishes the possibility of low-barrier intercell diffusion by purely zigzag mechanisms.

Sardar Sikandar Hayat; Marisol Alcántara Ortigoza; Muhammad A. Choudhry; Talat S. Rahman

2010-08-03T23:59:59.000Z

465

Software Tools  

Broader source: Energy.gov [DOE]

AMO’s tools help manufacturers increase industrial energy efficiency at the plant-level and in specific systems. Learn step-by-step ways to identify opportunities, monitor progress, and improve efficiency in any facility. Some tools help facilities implement an energy management system and prepare to become ISO 50001 and Superior Energy Performance certified.

466

NREL researchers are the first to use a high-performance com-puting tool for a large-eddy simulation of an entire wind plant.  

E-Print Network [OSTI]

at least 50% wastepaper, including 10% post consumer waste. NREL Develops Simulations forWind Plant Power-eddy simulation of an entire wind plant. Researchers at the National Renewable Energy Laboratory's (NREL) National an existing wind plant, augmenting previous studies of wind plant subsets. Wind turbines extract energy from

467

Energy conserving schemes for the simulation of musical instrument contact dynamics  

E-Print Network [OSTI]

Collisions are an innate part of the function of many musical instruments. Due to the nonlinear nature of contact forces, special care has to be taken in the construction of numerical schemes for simulation and sound synthesis. Finite difference schemes and other time-stepping algorithms used for musical instrument modelling purposes are normally arrived at by discretising a Newtonian description of the system. However because impact forces are non-analytic functions of the phase space variables, algorithm stability can rarely be established this way. This paper presents a systematic approach to deriving energy conserving schemes for frictionless impact modelling. The proposed numerical formulations follow from discretising Hamilton's equations of motion, generally leading to an implicit system of nonlinear equations that can be solved with Newton's method. The approach is first outlined for point mass collisions and then extended to distributed settings, such as vibrating strings and beams colliding with rig...

Chatziioannou, Vasileios

2015-01-01T23:59:59.000Z

468

Molecular Simulation of Fracture Dynamics of Symmetric Tilt Grain Boundaries in Graphene  

E-Print Network [OSTI]

Atomistic simulations were utilized to obtain microscopic information of the elongation process in graphene sheets consisting of various embedded symmetric tilt grain boundaries (GBs). In contrast to pristine graphene, these GBs fractured in an extraordinary pattern under transverse uniaxial elongation in all but the largest misorientation angle case, which exhibited intermittent crack propagation and formed many stringy residual connections after quasi mechanical failure. The strings known as monoatomic carbon chains (MACCs), whose importance was recently highlighted, gradually extended to a maximum of a few nanometers as the elongation proceeded. These features, which critically affect the tensile stress and the shape of stress-strain curve, were observed in both armchair and zigzag-oriented symmetric tilt GBs. However, there exist remarkable differences in the population density and the achievable length of MACCs appearing after quasi mechanical failure which were higher in the zigzag-oriented GBs. In addi...

Jhon, Young In; Smith, Robert; Jhon, Myung S

2012-01-01T23:59:59.000Z

469

Implementation of a torque and a collective pitch controller in a wind turbine simulator to characterize the dynamics at three control regions  

Science Journals Connector (OSTI)

Abstract As the capacity of wind turbines has increased, the loads on crucial components such as a gearbox, a generator, and blades are significantly increasing. An intelligent online monitoring system is indispensable to protect the excessive load on core components and manage a wind farm efficiently. In order to verify new online monitoring and diagnostic methods for such a monitoring system in advance, a wind turbine simulator is essential. For this purpose, we developed a simulator that has similar dynamics to an actual 3 MW wind turbine, and is thereby able to acquire a state of operation that closely resembles that of the 3 MW wind turbine under a variety of wind conditions. This paper describes the implementation of a torque and a collective pitch controller, which is used for a new type of simulator with the intention of exploiting online monitoring and diagnostic methods. The torque and the collective pitch controllers were developed to facilitate variable speed-variable pitch control strategies in the wind turbine simulator. Experiments demonstrated that three control regions were successfully deployed on the simulator, and thereby the simulator was operated at all control regions in a stable and accurate manner. Moreover, the strain and vibration measured from the blade and the gearbox showed different trends at three control regions. Therefore, a new type of simulator is an effective means to develop diagnostic and prognostic algorithms as well as online monitoring methods reflecting the dependency of dynamic characteristics on the control regions.

Ki-Yong Oh; Joon-Young Park; Jun-Shin Lee; JaeKyung Lee

2014-01-01T23:59:59.000Z

470

An ontology for trajectory simulation  

Science Journals Connector (OSTI)

From the concept exploration for a weapon system to training simulators, from hardware-in-the-loop simulators to mission planning tools, trajectory simulations are used throughout the life cycle of a weapon system. A trajectory simulation can be defined ...

Umut Durak; Halit Oguztuzun; S. Kemal Ider

2006-12-01T23:59:59.000Z

471

The 1st International Symposium on Micro & Nano Technology, 14-17 March, 2004, Honolulu, Hawaii, USA MOLECULAR DYNAMICS SIMULATIONS OF HEAT TRANSFER ISSUES  

E-Print Network [OSTI]

, USA MOLECULAR DYNAMICS SIMULATIONS OF HEAT TRANSFER ISSUES IN CARBON NANOTUBES S. Maruyama, Y-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, JAPAN ABSTRACT Several heat transfer problems related to single, and thermal boundary resistance in a junction of nanotubes are reviewed. Then, the heat transfer from an SWNT

Maruyama, Shigeo

472

Molecular dynamics simulations of hydrogen bombardment of tungsten carbide surfaces P. Trskelin,1 N. Juslin,1 P. Erhart,2 and K. Nordlund1  

E-Print Network [OSTI]

Molecular dynamics simulations of hydrogen bombardment of tungsten carbide surfaces P. Träskelin,1 and tungsten carbide WC is of interest both due to the use of hydrogen-containing plasmas in thin. INTRODUCTION Tungsten carbide WC exhibits extraordinary hardness and temperature resistance. It has long been

Nordlund, Kai

473

Vibrational Sum Frequency Spectroscopy and Molecular Dynamics Simulation of the Carbon Tetrachloride-Water and 1,2-Dichloroethane-Water Interfaces  

E-Print Network [OSTI]

and bonding at the carbon tetrachloride-water (CCl4-H2O) and the 1,2-dichloroethane-water (DCE-H2O) liquidVibrational Sum Frequency Spectroscopy and Molecular Dynamics Simulation of the Carbon Tetrachloride-Water and 1,2-Dichloroethane-Water Interfaces Dave S. Walker, Fred G. Moore, and Geraldine L

Richmond, Geraldine L.

474

Dynamic volume vs respiratory correlated 4DCT for motion assessment in radiation therapy simulation  

SciTech Connect (OSTI)

Purpose: Conventional (i.e., respiratory-correlated) 4DCT exploits the repetitive nature of breathing to provide an estimate of motion; however, it has limitations due to binning artifacts and irregular breathing in actual patient breathing patterns. The aim of this work was to evaluate the accuracy and image quality of a dynamic volume, CT approach (4D{sub vol}) using a 320-slice CT scanner to minimize these limitations, wherein entire image volumes are acquired dynamically without couch movement. This will be compared to the conventional respiratory-correlated 4DCT approach (RCCT). Methods: 4D{sub vol} CT was performed and characterized on an in-house, programmable respiratory motion phantom containing multiple geometric and morphological ''tumor'' objects over a range of regular and irregular patient breathing traces obtained from 3D fluoroscopy and compared to RCCT. The accuracy of volumetric capture and breathing displacement were evaluated and compared with the ground truth values and with the results reported using RCCT. A motion model was investigated to validate the number of motion samples needed to obtain accurate motion probability density functions (PDF). The impact of 4D image quality on this accuracy was then investigated. Dose measurements using volumetric and conventional scan techniques were also performed and compared. Results: Both conventional and dynamic volume 4DCT methods were capable of estimating the programmed displacement of sinusoidal motion, but patient breathing is known to not be regular, and obvious differences were seen for realistic, irregular motion. The mean RCCT amplitude error averaged at 4 mm (max. 7.8 mm) whereas the 4D{sub vol} CT error stayed below 0.5 mm. Similarly, the average absolute volume error was lower with 4D{sub vol} CT. Under irregular breathing, the 4D{sub vol} CT method provides a close description of the motion PDF (cross-correlation 0.99) and is able to track each object, whereas the RCCT method results in a significantly different PDF from the ground truth, especially for smaller tumors (cross-correlation ranging between 0.04 and 0.69). For the protocols studied, the dose measurements were higher in the 4D{sub vol} CT method (40%), but it was shown that significant mAs reductions can be achieved by a factor of 4-5 while maintaining image quality and accuracy. Conclusions: 4D{sub vol} CT using a scanner with a large cone-angle is a promising alternative for improving the accuracy with which respiration-induced motion can be characterized, particularly for patients with irregular breathing motion. This approach also generates 4DCT image data with a reduced total scan time compared to a RCCT scan, without the need for image binning or external respiration signals within the 16 cm scan length. Scan dose can be made comparable to RCCT by optimization of the scan parameters. In addition, it provides the possibility of measuring breathing motion for more than one breathing cycle to assess stability and obtain a more accurate motion PDF, which is currently not feasible with the conventional RCCT approach.

Coolens, Catherine; Bracken, John; Driscoll, Brandon; Hope, Andrew; Jaffray, David [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3S2 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3S2 (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario M5G 2M9 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3S2 (Canada) and Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9 (Canada)

2012-05-15T23:59:59.000Z

475

Dynamics of the Solar Magnetic Network: Two-dimensional MHD Simulations  

E-Print Network [OSTI]

The aim of this work is to identify the physical processes that occur in the network and contribute to its dynamics and heating. We model the network as consisting of individual flux tubes with a non-potential field structure that are located in intergranular lanes. With a typical horizontal size of 200 km at the base of the photosphere, they expand upward and merge with their neighbors at a height of about 600 km. Above a height of approximately 1000 km the magnetic field starts to become uniform. Waves are generated in this medium by means of motions at the lower boundary. We focus on transverse driving, which generates both fast and slow waves within a flux tube and acoustic waves at the interface of the tube and the field-free medium. The acoustic waves at the interface are due to compression of the gas on one side of the flux tube and expansion on the other. These waves travel upward along the two sides of the (2D) flux tube and enter it, where they become longitudinal waves. For impulsive excitation with a time constant of 120 s, we find that a dominant feature is the creation of vortical motions that propagate upward. We have identified an efficient mechanism for the generation of longitudinal waves and shock formation in the chromospheric part of the flux concentration. We examine some broad implications of our results.

S. S. Hasan; A. A. van Ballegoiijen; W. Kalkofen; O. Steiner

2005-03-24T23:59:59.000Z

476

A coarse-graining approach for molecular simulation that retains the dynamics of the all-atom reference system by implementing hydrodynamic interactions  

SciTech Connect (OSTI)

We report on a new approach for deriving coarse-grained intermolecular forces that retains the frictional contribution that is often discarded by conventional coarse-graining methods. The approach is tested for water and an aqueous glucose solution, and the results from the new implementation for coarse-grained molecular dynamics simulation show remarkable agreement with the dynamics obtained from reference all-atom simulations. The agreement between the structural properties observed in the coarse-grained and all-atom simulations is also preserved. We discuss how this approach may be applied broadly to any existing coarse-graining method where the coarse-grained models are rigorously derived from all-atom reference systems.

Markutsya, Sergiy [Ames Laboratory; Lamm, Monica H [Ames Laboratory

2014-11-07T23:59:59.000Z

477

Validation of a Building Simulation Tool Using Field Data for Three Identical Configuration Full-Serve Restaurants Using Different HVAC Systems  

E-Print Network [OSTI]

A new building application for a pre-existing HVAC software tool which calculates the benefits of desiccant-assisted HVAC equipment versus the performance of a standard vapor-compression system is used to model the monitored results, see Yborra...

Brillhart, P. L.; Worek, W. M.

2000-01-01T23:59:59.000Z

478

Sandia National Laboratories: open source WEC modeling tool  

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

open source WEC modeling tool Sandia, NREL Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim On July 29, 2014, in Computational Modeling & Simulation, Energy,...

479

Dynamic  

Office of Legacy Management (LM)

Dynamic Dynamic , and Static , Res.ponse of the Government Oil Shale Mine at ' , . , Rifle, Colorado, to the Rulison Event. , . ; . . DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. p ( y c - - a 2-1 0 -4- REPORT AT (29-2) 914 USBM 1 0 0 1 UNITED STATES DEPARTMENT O F THE I NTERIOR BUREAU OF MINES e s.09 P. L. R U S S E L L RESEARCH D l RECTOR Februory 2, lB7O DYNAMIC AND STATIC RESPONSE 'OF THE GOVERNMENT OIL SHALE MINE A T RIFLE, COLORADO, T O THE, RULISON EVENT ORDER FROM CFSTl A S ~ B ~ &J C / This page intentionally left blank CONTENTS Page . . . . . . . . . . . . . . . . . . . . . . . . . H i s t o r i c . a l Des c r i p t i o n 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Summary 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Introduction 3

480

Prioritization Tool  

Broader source: Energy.gov [DOE]

BTO has developed the Prioritization Tool to provide analytical support for its programmatic decision-making and to further accelerate the transformation of the U.S. building energy efficiency sector.

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