Xing, Lu [Oklahoma State University; Cullin, James [Oklahoma State University; Spitler, Jeffery [Oklahoma State University; Im, Piljae [ORNL; Fisher, Daniel [Oklahoma State University
2011-01-01T23:59:59.000Z
A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.
Development and validation of a vertically two-dimensional mesoscale numerical model
Walters, Michael Kent
1985-01-01T23:59:59.000Z
values of model variables for static test and kinetic energy calculations . . . . . . . . . 25 2 Results of kinetic energy budget calculations . . 29 ? 1 -5 Surface heating rate (K s x 10 ) . . . . . . . 32 4 Initial values of variables for nonlinear.... These tests provide an important means of debugging the numerical scheme. The validation tests performed on the mesoscale model consisted of a simple static test, calculation of the mass continuity and the kinet. ic energy budget, and performing non...
Bruneau, Steve
in Pack Ice Roelof C. Dragt Offshore Engineering Faculty of Mechanical, Maritime and Material Engineering of experiments to validate a Graphics Processing Unit based numerical modelling of ship operations in 2D pack ice interaction, 2D Model Experiments, Image Processing. I. INTRODUCTION A ship travelling through pack ice
Banerjee, Debjyoti
microfluidics Jonathan Siegrist,*a Mary Amasia,a Navdeep Singh,b Debjyoti Banerjeeb and Marc Madoua Received 1st analysis of microchamber filling in centrifugal microfluidics is presented. In the development of micro on centrifugal microfluidic platforms, numerical modeling using the Volume of Fluids method is performed
Model Validation and Spatial Interpolation by Combining Observations with Outputs from Numerical
Washington at Seattle, University of
""r,c,rn The authors are for hel]JfuI #12;Abstract Constructing maps of pollution levels is vital for air quality concentrations. Key tlJords: air pollution, Ba~yesian inference, change of support, likelihood approaches, Matern Resolutions 2.5 Modeling a Nonstationary Covariance . 3 Estimation 3.1 Algorithm 4 Application: Air Pollution
Experimental Validation of a Numerical Multizone Airflow and Pollutant Transfer Model
Paris-Sud XI, Université de
and long-term assessment of the performances of ventilation systems, the experimental house MARIA and ventilation systems are modeled in MATLAB/Simulink environment. This paper quickly describes the multi exhaust, balanced and natural ventilation systems. In addition, the virtual laboratory SIMBAD Building
Baudouin, Lucie
A controlled distributed parameter model for a fluid-flexible structure system: numerical consider the problem of active reduction of vibrations in a fluid-flexible structure system and the sloshing of the fuel inside the wing's tank. The control is performed using piezoelectric patches
Model Validation Status Review
E.L. Hardin
2001-11-28T23:59:59.000Z
The primary objective for the Model Validation Status Review was to perform a one-time evaluation of model validation associated with the analysis/model reports (AMRs) containing model input to total-system performance assessment (TSPA) for the Yucca Mountain site recommendation (SR). This review was performed in response to Corrective Action Request BSC-01-C-01 (Clark 2001, Krisha 2001) pursuant to Quality Assurance review findings of an adverse trend in model validation deficiency. The review findings in this report provide the following information which defines the extent of model validation deficiency and the corrective action needed: (1) AMRs that contain or support models are identified, and conversely, for each model the supporting documentation is identified. (2) The use for each model is determined based on whether the output is used directly for TSPA-SR, or for screening (exclusion) of features, events, and processes (FEPs), and the nature of the model output. (3) Two approaches are used to evaluate the extent to which the validation for each model is compliant with AP-3.10Q (Analyses and Models). The approaches differ in regard to whether model validation is achieved within individual AMRs as originally intended, or whether model validation could be readily achieved by incorporating information from other sources. (4) Recommendations are presented for changes to the AMRs, and additional model development activities or data collection, that will remedy model validation review findings, in support of licensing activities. The Model Validation Status Review emphasized those AMRs that support TSPA-SR (CRWMS M&O 2000bl and 2000bm). A series of workshops and teleconferences was held to discuss and integrate the review findings. The review encompassed 125 AMRs (Table 1) plus certain other supporting documents and data needed to assess model validity. The AMRs were grouped in 21 model areas representing the modeling of processes affecting the natural and engineered barriers, plus the TSPA model itself Description of the model areas is provided in Section 3, and the documents reviewed are described in Section 4. The responsible manager for the Model Validation Status Review was the Chief Science Officer (CSO) for Bechtel-SAIC Co. (BSC). The team lead was assigned by the CSO. A total of 32 technical specialists were engaged to evaluate model validation status in the 21 model areas. The technical specialists were generally independent of the work reviewed, meeting technical qualifications as discussed in Section 5.
Model Verification and Validation
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your1 SECTION A.Model Verification and Validation Engineering
Structural system identification: Structural dynamics model validation
Red-Horse, J.R.
1997-04-01T23:59:59.000Z
Structural system identification is concerned with the development of systematic procedures and tools for developing predictive analytical models based on a physical structure`s dynamic response characteristics. It is a multidisciplinary process that involves the ability (1) to define high fidelity physics-based analysis models, (2) to acquire accurate test-derived information for physical specimens using diagnostic experiments, (3) to validate the numerical simulation model by reconciling differences that inevitably exist between the analysis model and the experimental data, and (4) to quantify uncertainties in the final system models and subsequent numerical simulations. The goal of this project was to develop structural system identification techniques and software suitable for both research and production applications in code and model validation.
Feature extraction for structural dynamics model validation
Hemez, Francois [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Nishio, Mayuko [UNIV OF TOKYO; Worden, Keith [UNIV OF SHEFFIELD; Takeda, Nobuo [UNIV OF TOKYO
2010-11-08T23:59:59.000Z
This study focuses on defining and comparing response features that can be used for structural dynamics model validation studies. Features extracted from dynamic responses obtained analytically or experimentally, such as basic signal statistics, frequency spectra, and estimated time-series models, can be used to compare characteristics of structural system dynamics. By comparing those response features extracted from experimental data and numerical outputs, validation and uncertainty quantification of numerical model containing uncertain parameters can be realized. In this study, the applicability of some response features to model validation is first discussed using measured data from a simple test-bed structure and the associated numerical simulations of these experiments. issues that must be considered were sensitivity, dimensionality, type of response, and presence or absence of measurement noise in the response. Furthermore, we illustrate a comparison method of multivariate feature vectors for statistical model validation. Results show that the outlier detection technique using the Mahalanobis distance metric can be used as an effective and quantifiable technique for selecting appropriate model parameters. However, in this process, one must not only consider the sensitivity of the features being used, but also correlation of the parameters being compared.
Numerical Modeling of HCCI Combustion
Broader source: Energy.gov (indexed) [DOE]
Numerical Modeling of HCCI Combustion Salvador M. Aceves, Daniel L. Flowers, J. Ray Smith, Joel Martinez-Frias, Francisco Espinosa-Loza, Tim Ross, Bruce Buchholz, Nick...
Model Verification and Validation
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'. William Hirst Hirst Enterprises,MODEL STANDARDS
Numerical studies of the metamodel fitting and validation processes
Boyer, Edmond
algorithms and application to a nuclear safety computer code show the relevance of this new sequential this problem consists in replacing cpu time expensive computer models by cpu inexpensive mathematical functions to fit the metamodel) has to provide adequate space filling properties. We adopt a numerical approach
Studied models Numerical scheme
Helluy, Philippe
: Sound speed: c0 = 1500m/s Pressure: p0 = 105Pa Density: 0 = 1000kg/m3 Vapor: 1 = 1.4 (1 = 0) Water: 2. Helluy, S. MÂ¨uller HÂ´el`ene Mathis Micro-Macro Modelling and Simulation of Liquid-Vapour Flows #12 approximations HÂ´el`ene Mathis Micro-Macro Modelling and Simulation of Liquid-Vapour Flows #12;Studied models
Model Validation with Hybrid Dynamic Simulation
Huang, Zhenyu; Kosterev, Dmitry; Guttromson, Ross T.; Nguyen, Tony B.
2006-06-18T23:59:59.000Z
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.
Lattice Boltzmann Model for Numerical Relativity
Ilseven, E
2015-01-01T23:59:59.000Z
In the Bona-Masso formulation, Einstein equations are written as a set of flux conservative first order hyperbolic equations that resemble fluid dynamics equations. Based on this formulation, we construct a lattice Boltzmann model for Numerical Relativity. Our model is validated with well-established tests, showing good agreement with analytical solutions. Furthermore, we show that by increasing the relaxation time, we gain stability at the cost of losing accuracy, and by decreasing the lattice spacings while keeping a constant numerical diffusivity, the accuracy and stability of our simulations improves. Finally, in order to show the potential of our approach a linear scaling law for parallelisation with respect to number of CPU cores is demonstrated. Our model represents the first step in using lattice kinetic theory to solve gravitational problems.
Nuclear Systems Modeling, Simulation & Validation | ORNL
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Systems Modeling and Simulation SHARE Nuclear Systems Modeling, Simulation and Validation Reactor physics depletion model for the Advanced Test Reactor Reactor physics depletion...
Model Validation with Hybrid Dynamic Simulation
Huang, Zhenyu; Kosterev, Dmitry; Guttromson, Ross T.; Nguyen, Tony B.
2006-06-22T23:59:59.000Z
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.
Modeling and Validation of Pipeline Specifications
Mishra, Prabhat
-on-Chip design process. Many existing approaches employ a bottom-up approach to pipeline validation, where description language (ADL) constructs, and thus allows a powerful top-down approach to pipeline validationModeling and Validation of Pipeline Specifications PRABHAT MISHRA and NIKIL DUTT University
Maui Electrical System Simulation Model Validation
Maui Electrical System Simulation Model Validation Prepared for the U.S. Department of Energy Office of Electricity Delivery and Energy Reliability Under Award No. DE-FC-06NT42847 Task 9 Deliverable Baseline Model Validation By GE Global Research Niskayuna, New York And University of Hawaii Hawaii Natural
Design, Modeling, and Validation of a Flame Reformer for LNT...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Design, Modeling, and Validation of a Flame Reformer for LNT External Bypass Regeneration Design, Modeling, and Validation of a Flame Reformer for LNT External Bypass Regeneration...
Demonstrating and Validating a Next Generation Model-Based Controller...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
and Validating a Next Generation Model-Based Controller for Fuel Efficient, Low Emissions Diesel Engines Demonstrating and Validating a Next Generation Model-Based Controller for...
Probabilistic Methods for Model Validation
Halder, Abhishek
2014-05-01T23:59:59.000Z
Instead of Moments or Sets . . . . . 6 1.3.4 Methodology and Organization . . . . . . . . . . . . . . . . . 8 1.4 Contributions of This Dissertation . . . . . . . . . . . . . . . . . . . . 9 2. UNCERTAINTY PROPAGATION FOR DETERMINISTIC FLOW . . . . 12 2...’s Density Function Based Model Fal- sification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 4.6 Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 xv 5. CASE STUDY: F-16 CONTROLLER ROBUSTNESS VERIFICATION...
Numerical wind speed simulation model
Ramsdell, J.V.; Athey, G.F.; Ballinger, M.Y.
1981-09-01T23:59:59.000Z
A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared.
Low frequency eddy current benchmark study for model validation
Mooers, R. D.; Boehnlein, T. R. [University of Dayton Research Institute, Structural Integrity Division, Dayton, OH, 45469 (United States); Cherry, M. R.; Knopp, J. S. [Air Force Research Lab, NDE Division, Wright Patterson, OH 45433 (United States); Aldrin, J. C. [Computational Tools, Gurnee, IL 60031 (United States); Sabbagh, H. A. [Victor Technologies LLC, Bloomington, IN 47401 (United States)
2011-06-23T23:59:59.000Z
This paper presents results of an eddy current model validation study. Precise measurements were made using an impedance analyzer to investigate changes in impedance due to Electrical Discharge Machining (EDM) notches in aluminum plates. Each plate contained one EDM notch at an angle of 0, 10, 20, or 30 degrees from the normal of the plate surface. Measurements were made with the eddy current probe both scanning parallel and perpendicular to the notch length. The experimental response from the vertical and oblique notches will be reported and compared to results from different numerical simulation codes.
Numerical Model for Conduction-Cooled Current Lead Heat Loads
White, M.J.; Wang, X.L.; /Fermilab; Brueck, H.D.; /DESY
2011-06-10T23:59:59.000Z
Current leads are utilized to deliver electrical power from a room temperature junction mounted on the vacuum vessel to a superconducting magnet located within the vacuum space of a cryostat. There are many types of current leads used at laboratories throughout the world; however, conduction-cooled current leads are often chosen for their simplicity and reliability. Conduction-cooled leads have the advantage of using common materials, have no superconducting/normal state transition, and have no boil-off vapor to collect. This paper presents a numerical model for conduction-cooled current lead heat loads. This model takes into account varying material and fluid thermal properties, varying thicknesses along the length of the lead, heat transfer in the circumferential and longitudinal directions, electrical power dissipation, and the effect of thermal intercepts. The model is validated by comparing the numerical model results to ideal cases where analytical equations are valid. In addition, the XFEL (X-Ray Free Electron Laser) prototype current leads are modeled and compared to the experimental results from testing at DESY's XFEL Magnet Test Stand (XMTS) and Cryomodule Test Bench (CMTB).
High performance computing and numerical modelling
,
2014-01-01T23:59:59.000Z
Numerical methods play an ever more important role in astrophysics. This is especially true in theoretical works, but of course, even in purely observational projects, data analysis without massive use of computational methods has become unthinkable. The key utility of computer simulations comes from their ability to solve complex systems of equations that are either intractable with analytic techniques or only amenable to highly approximative treatments. Simulations are best viewed as a powerful complement to analytic reasoning, and as the method of choice to model systems that feature enormous physical complexity such as star formation in evolving galaxies, the topic of this 43rd Saas Fee Advanced Course. The organizers asked me to lecture about high performance computing and numerical modelling in this winter school, and to specifically cover the basics of numerically treating gravity and hydrodynamics in the context of galaxy evolution. This is still a vast field, and I necessarily had to select a subset ...
Validation Analysis of the Shoal Groundwater Flow and Transport Model
A. Hassan; J. Chapman
2008-11-01T23:59:59.000Z
Environmental restoration at the Shoal underground nuclear test is following a process prescribed by a Federal Facility Agreement and Consent Order (FFACO) between the U.S. Department of Energy, the U.S. Department of Defense, and the State of Nevada. Characterization of the site included two stages of well drilling and testing in 1996 and 1999, and development and revision of numerical models of groundwater flow and radionuclide transport. Agreement on a contaminant boundary for the site and a corrective action plan was reached in 2006. Later that same year, three wells were installed for the purposes of model validation and site monitoring. The FFACO prescribes a five-year proof-of-concept period for demonstrating that the site groundwater model is capable of producing meaningful results with an acceptable level of uncertainty. The corrective action plan specifies a rigorous seven step validation process. The accepted groundwater model is evaluated using that process in light of the newly acquired data. The conceptual model of ground water flow for the Project Shoal Area considers groundwater flow through the fractured granite aquifer comprising the Sand Springs Range. Water enters the system by the infiltration of precipitation directly on the surface of the mountain range. Groundwater leaves the granite aquifer by flowing into alluvial deposits in the adjacent basins of Fourmile Flat and Fairview Valley. A groundwater divide is interpreted as coinciding with the western portion of the Sand Springs Range, west of the underground nuclear test, preventing flow from the test into Fourmile Flat. A very low conductivity shear zone east of the nuclear test roughly parallels the divide. The presence of these lateral boundaries, coupled with a regional discharge area to the northeast, is interpreted in the model as causing groundwater from the site to flow in a northeastward direction into Fairview Valley. Steady-state flow conditions are assumed given the absence of groundwater withdrawal activities in the area. The conceptual and numerical models were developed based upon regional hydrogeologic investigations conducted in the 1960s, site characterization investigations (including ten wells and various geophysical and geologic studies) at Shoal itself prior to and immediately after the test, and two site characterization campaigns in the 1990s for environmental restoration purposes (including eight wells and a year-long tracer test). The new wells are denoted MV-1, MV-2, and MV-3, and are located to the northnortheast of the nuclear test. The groundwater model was generally lacking data in the north-northeastern area; only HC-1 and the abandoned PM-2 wells existed in this area. The wells provide data on fracture orientation and frequency, water levels, hydraulic conductivity, and water chemistry for comparison with the groundwater model. A total of 12 real-number validation targets were available for the validation analysis, including five values of hydraulic head, three hydraulic conductivity measurements, three hydraulic gradient values, and one angle value for the lateral gradient in radians. In addition, the fracture dip and orientation data provide comparisons to the distributions used in the model and radiochemistry is available for comparison to model output. Goodness-of-fit analysis indicates that some of the model realizations correspond well with the newly acquired conductivity, head, and gradient data, while others do not. Other tests indicated that additional model realizations may be needed to test if the model input distributions need refinement to improve model performance. This approach (generating additional realizations) was not followed because it was realized that there was a temporal component to the data disconnect: the new head measurements are on the high side of the model distributions, but the heads at the original calibration locations themselves have also increased over time. This indicates that the steady-state assumption of the groundwater model is in error. To test the robustness of the model d
Gokaltun, Seckin; Munroe, Norman; Subramaniam, Shankar
2014-12-31T23:59:59.000Z
This study presents a new drag model, based on the cohesive inter-particle forces, implemented in the MFIX code. This new drag model combines an existing standard model in MFIX with a particle-based drag model based on a switching principle. Switches between the models in the computational domain occur where strong particle-to-particle cohesion potential is detected. Three versions of the new model were obtained by using one standard drag model in each version. Later, performance of each version was compared against available experimental data for a fluidized bed, published in the literature and used extensively by other researchers for validation purposes. In our analysis of the results, we first observed that standard models used in this research were incapable of producing closely matching results. Then, we showed for a simple case that a threshold is needed to be set on the solid volume fraction. This modification was applied to avoid non-physical results for the clustering predictions, when governing equation of the solid granular temperate was solved. Later, we used our hybrid technique and observed the capability of our approach in improving the numerical results significantly; however, improvement of the results depended on the threshold of the cohesive index, which was used in the switching procedure. Our results showed that small values of the threshold for the cohesive index could result in significant reduction of the computational error for all the versions of the proposed drag model. In addition, we redesigned an existing circulating fluidized bed (CFB) test facility in order to create validation cases for clustering regime of Geldart A type particles.
Bornemann, Jens
, 217Â229 (1997) SPECTRAL-DOMAIN MODELLING OF SUPERCONDUCTING MICROSTRIP STRUCTURES smain amari with available data to document the validity of the approach. Â© 1997 by John Wiley & Sons, Ltd. Int. J. Numer. Model., 10, 217Â229 (1997) No. of Figures: 9. No. of Tables: 0. No. of References: 18. 1. INTRODUCTION
Validating agent based models through virtual worlds.
Lakkaraju, Kiran; Whetzel, Jonathan H.; Lee, Jina [Sandia National Laboratories, Livermore, CA; Bier, Asmeret Brooke; Cardona-Rivera, Rogelio E. [North Carolina State University, Raleigh, NC; Bernstein, Jeremy Ray Rhythm [Gaikai, Inc., Aliso Viejo, CA
2014-01-01T23:59:59.000Z
As the US continues its vigilance against distributed, embedded threats, understanding the political and social structure of these groups becomes paramount for predicting and dis- rupting their attacks. Agent-based models (ABMs) serve as a powerful tool to study these groups. While the popularity of social network tools (e.g., Facebook, Twitter) has provided extensive communication data, there is a lack of ne-grained behavioral data with which to inform and validate existing ABMs. Virtual worlds, in particular massively multiplayer online games (MMOG), where large numbers of people interact within a complex environ- ment for long periods of time provide an alternative source of data. These environments provide a rich social environment where players engage in a variety of activities observed between real-world groups: collaborating and/or competing with other groups, conducting battles for scarce resources, and trading in a market economy. Strategies employed by player groups surprisingly re ect those seen in present-day con icts, where players use diplomacy or espionage as their means for accomplishing their goals. In this project, we propose to address the need for ne-grained behavioral data by acquiring and analyzing game data a commercial MMOG, referred to within this report as Game X. The goals of this research were: (1) devising toolsets for analyzing virtual world data to better inform the rules that govern a social ABM and (2) exploring how virtual worlds could serve as a source of data to validate ABMs established for analogous real-world phenomena. During this research, we studied certain patterns of group behavior to compliment social modeling e orts where a signi cant lack of detailed examples of observed phenomena exists. This report outlines our work examining group behaviors that underly what we have termed the Expression-To-Action (E2A) problem: determining the changes in social contact that lead individuals/groups to engage in a particular behavior. Results from our work indicate that virtual worlds have the potential for serving as a proxy in allocating and populating behaviors that would be used within further agent-based modeling studies.
Numerical modeling of vertical cavity semiconductor lasers
Chow, W.W.; Hadley, G.R.
1996-08-01T23:59:59.000Z
A vertical cavity surface emitting laser (VCSEL) is a diode laser whose optical cavity is formed by growing or depositing DBR mirror stacks that sandwich an active gain region. The resulting short cavity supports lasing into a single longitudinal mode normal to the wafer, making these devices ideal for a multitude of applications, ranging from high-speed communication to high-power sources (from 2D arrays). This report describes the development of a numerical VCSEL model, whose goal is to both further their understanding of these complex devices and provide a tool for accurate design and data analysis.
Argonne X-rays validate quantum magnetism model | Argonne National...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
National Laboratory and Max Planck Institute for Solid State Research in Stuttgart, Germany have validated a theorized model of quantum magnetism by observing it firsthand in a...
Validation of Material Models for Automotive Carbon Fiber Composite...
Broader source: Energy.gov (indexed) [DOE]
Validation of Material Models for Automotive Carbon Fiber Composite Structures (VMM) Libby Berger (General Motors), Omar Faruque (Ford) Co-Principal Investigators US Automotive...
Thermal Hydraulic Modeling: Cross-Verification, Validation and...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Aleks Obabko, Paul Fischer, and Tim Tautges, Argonne National Laboratory Thermal Hydraulic Modeling: Cross-Verification, Validation and Co-design PI Name: Paul F. Fischer PI...
Validation of the Window Model of the Modelica Buildings Library
LBNL-5735E Validation of the Window Model of the Modelica Buildings Library Thierry Stephane MODEL OF THE MODELICA BUILDINGS LIBRARY Thierry Stephane Nouidui, Michael Wetter, and Wangda Zuo the validation of the window model of the free open-source Modelica Buildings library. This paper starts
SURVEY, ANALYSIS AND VALIDATION OF INFORMATION FOR BUSINESS PROCESS MODELING
SURVEY, ANALYSIS AND VALIDATION OF INFORMATION FOR BUSINESS PROCESS MODELING Nuno Castela Escola, Business Processes, Informational Resources, Activities, UML Abstract: Business processes modeling became a fundamental task for organizations. To model business processes is necessary to know all the activities
Chen, Qingyan "Yan"
1 Experimental Validation of a Computational Fluid Dynamics Model for IAQ applications in Ice Rink, USA, Fax: 617-432-4122, Abstract Many ice rink arenas have ice resurfacing equipment that uses fossil temperature distributions in ice rinks. The numerical results agree reasonably with the corresponding
NUMERICAL MODELING OF CATHODE CONTACT MATERIAL DENSIFICATION
Koeppel, Brian J.; Liu, Wenning N.; Stephens, Elizabeth V.; Khaleel, Mohammad A.
2011-11-01T23:59:59.000Z
Numerical modeling was used to simulate the constrained sintering process of the cathode contact layer during assembly of solid oxide fuel cells (SOFCs). A finite element model based on the continuum theory for sintering of porous bodies was developed and used to investigate candidate low-temperature cathode contact materials. Constitutive parameters for various contact materials under investigation were estimated from dilatometry screening tests, and the influence of processing time, processing temperature, initial grain size, and applied compressive stress on the free sintering response was predicted for selected candidate materials. The densification behavior and generated stresses within a 5-cell planar SOFC stack during sintering, high temperature operation, and room temperature shutdown were predicted. Insufficient constrained densification was observed in the stack at the proposed heat treatment, but beneficial effects of reduced grain size, compressive stack preload, and reduced thermal expansion coefficient on the contact layer densification and stresses were observed.
Minisymposium on Validated Methods: Applications to Modeling, Analysis,
Kreinovich, Vladik
in Medicine and Engineering Organizers: Andreas Rauh1 and Ekaterina Auer2 During the last decades, computer of the mathematical model of the considered process. In this minisymposium, we focus on validated methods as a meansMinisymposium on Validated Methods: Applications to Modeling, Analysis, and Design of Systems
System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report
Freeman, J.; Whitmore, J.; Kaffine, L.; Blair, N.; Dobos, A. P.
2013-12-01T23:59:59.000Z
The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail.
Detailed validation of an empirical model for viscous fingering with gravity effects
Fayers, F.J.; Newley, T.M.J.
1988-05-01T23:59:59.000Z
This paper extends to two-dimensional (2D) flows the derivation and validation of an empirical model for viscous fingering previously developed. Fine-scale numerical simulations are used to provide basic data for validating the approximations, and these fingering results are also checked against a range of experiments. The flow rate dependence of gravity segregation in vertical section experiments conducted by van der Poel is examined, where the broadly acceptable agreement of the empirical model is limited by some identified additional features.
A numerical model of aerosol scavenging
Bradley, M.M.; Molenkamp, C.R.
1991-10-01T23:59:59.000Z
Using a three-dimensional numerical cloud/smoke-plume model, we have simulated the burning of a large, mid-latitude city following a nuclear exchange. The model includes 18 dynamic and microphysical equations that predict the fire-driven airflow, cloud processes, and smoke-cloud interactions. In the simulation, the intense heating from the burning city produces a firestorm with updraft velocities exceeding 60 m/s. Within 15 minutes of ignition, the smoke plume penetrates the tropopause. The updraft triggers a cumulonimbus cloud that produces significant quantities of ice, snow, and hail. These solid hydrometeors, as well as cloud droplets and rain, interact with the smoke particles from the fire. At the end of the one-hour simulation, over 20% of the smoke is in slowly falling snowflakes. If the snow reaches the ground before the flakes completely sublimate (or melt and then evaporate), then only approximately 50% of the smoke will survive the scavenging processes and remain in the atmosphere to affect the global climate.
Fractional Euler-Bernoulli beams: theory, numerical study and experimental validation
Wojciech Sumelka; Tomasz Blaszczyk; Christian Liebold
2015-02-05T23:59:59.000Z
In this paper the classical Euler-Bernoulli beam (CEBB) theory is reformulated utilising fractional calculus. Such generalisation is called fractional Euler-Bernoulli beams (FEBB) and results in non-local spatial description. The parameters of the model are identified based on AFM experiments concerning bending rigidities of micro-beams made of the polymer SU-8. In experiments both force as well as deflection data were recorded revealing significant size effect with respect to outer dimensions of the specimens. Special attention is also focused on the proper numerical solution of obtained fractional differential equation.
Numerical Modeling At Dixie Valley Geothermal Area (McKenna ...
McKenna & Blackwell, 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Numerical Modeling At Dixie Valley Geothermal Area (McKenna &...
Numerical Modeling of the Nucleation Conditions of Petal-Centerline...
Coso Geothermal Field Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Numerical Modeling of the Nucleation Conditions of...
Ahmed Hassan
2003-01-01T23:59:59.000Z
Many sites of groundwater contamination rely heavily on complex numerical models of flow and transport to develop closure plans. This has created a need for tools and approaches that can be used to build confidence in model predictions and make it apparent to regulators, policy makers, and the public that these models are sufficient for decision making. This confidence building is a long-term iterative process and it is this process that should be termed ''model validation.'' Model validation is a process not an end result. That is, the process of model validation cannot always assure acceptable prediction or quality of the model. Rather, it provides safeguard against faulty models or inadequately developed and tested models. Therefore, development of a systematic approach for evaluating and validating subsurface predictive models and guiding field activities for data collection and long-term monitoring is strongly needed. This report presents a review of model validation studies that pertain to groundwater flow and transport modeling. Definitions, literature debates, previously proposed validation strategies, and conferences and symposia that focused on subsurface model validation are reviewed and discussed. The review is general in nature, but the focus of the discussion is on site-specific, predictive groundwater models that are used for making decisions regarding remediation activities and site closure. An attempt is made to compile most of the published studies on groundwater model validation and assemble what has been proposed or used for validating subsurface models. The aim is to provide a reasonable starting point to aid the development of the validation plan for the groundwater flow and transport model of the Faultless nuclear test conducted at the Central Nevada Test Area (CNTA). The review of previous studies on model validation shows that there does not exist a set of specific procedures and tests that can be easily adapted and applied to determine the validity of site-specific groundwater models. This is true for both deterministic and stochastic models, with the latter posing a more difficult and challenging problem when it comes to validation. This report then proposes a general validation approach for the CNTA model, which addresses some of the important issues recognized in previous validation studies, conferences, and symposia as crucial to the process. The proposed approach links model building, model calibration, model predictions, data collection, model evaluations, and model validation in an iterative loop. The approach focuses on use of collected validation data to reduce model uncertainty and narrow the range of possible outcomes of stochastic numerical models. It accounts for the stochastic nature of the numerical CNTA model, which used Monte Carlo simulation approach. The proposed methodology relies on the premise that absolute validity is not even a theoretical possibility and is not a regulatory requirement. Rather, it highlights the importance of testing as many aspects of the model as possible and using as many diverse statistical tools as possible for rigorous checking and confidence building in the model and its predictions. It is this confidence that will eventually allow for regulator and public acceptance of decisions based on the model predictions.
Buoyant melting instabilities beneath extending lithosphere: 1. Numerical models
Tackley, Paul J.
Buoyant melting instabilities beneath extending lithosphere: 1. Numerical models John W. Hernlund,1,2 Paul J. Tackley,1,3 and David J. Stevenson4 Received 18 November 2006; revised 18 October 2007 diffusely extending lithosphere is studied using numerical convection models covering a wide range
Evolution of the Bohemian Massif: Insights from numerical modeling
Cerveny, Vlastislav
Evolution of the Bohemian Massif: Insights from numerical modeling Petra Maierová Supervisor: Doc of Geophysics Faculty of Mathematics and Physics Charles University in Prague #12;February 4, 2013Evolution Conclusions Outline #12;February 4, 2013Evolution of the Bohemian Massif: Insights from numerical modeling 3
NUMERICAL MODELING FOR MULTIPHASE INCOMPRESSIBLE FLOW WITH PHASE CHANGE
Abdou, Mohamed
NUMERICAL MODELING FOR MULTIPHASE INCOMPRESSIBLE FLOW WITH PHASE CHANGE Xiao-Yong Luo, Ming-Jiu Ni for multiphase flows. A con- tinuum surface force (CSF) tension model is used in the present cases. Phase change
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Qualifying geospatial workflow models for adaptive controlled validity and accuracy
Stock, Kristin
Qualifying geospatial workflow models for adaptive controlled validity and accuracy Didier Leibovici, Gobe Hobona, Kristin Stock and Mike Jackson Centre for Geospatial Sciences, University.leibovici@nottingham.ac.uk Abstract--Sharing geospatial data and geoprocessing models within a system like GEOSS (Global Earth
Predicting Vehicle Crashworthiness: Validation of Computer Models for
Berger, Jim
Predicting Vehicle Crashworthiness: Validation of Computer Models for Functional and Hierarchical. Cafeo, Chin-Hsu Lin, and Jian Tu Abstract The CRASH computer model simulates the effect of a vehicle colliding against different barrier types. If it accurately represents real vehicle crash- worthiness
Numerical study of energy diffusion in King models
Tom Theuns
1995-11-07T23:59:59.000Z
The energy diffusion coefficients D_n(E) (n=1,2) for a system of equal mass particles moving self-consistently in an N-body realisation of a King model are computed from the probability per unit time, P(E, Delta E), that a star with initial energy E will undergo an energy change Delta E. In turn, P is computed from the number of times during the simulation that a particle in a state of given energy undergoes a transition to another state. These particle states are defined directly from the time evolution of E by identifying them with the event occuring between two local maxima in the E(t) curve. If one assumes next that energy changes are uncorrelated between different states, one can use diffusion theory to compute D_n(E). The simulations employ N=512, 2048,... , 32768 particles and are performed using an implementation of Aarseth's direct integrator N-body1 on a massively parallel computer. The more than seven million transitions measured in the largest N simulation provide excellent statistics. The numerically determined D(E)'s are compared against their theoretical counterparts which are computed from phase-space averaged rates of energy change due to independent binary encounters. The overall agreement between them is impressive over most of the energy range, notwithstanding the very different type of approximations involved, giving considerable support to the valid usage of these theoretical expressions to simulate dynamical evolution in Fokker-Planck type calculations.
Scan welding: Thermomechanical model and experimental validation
Fourligkas, N.; Doumanidis, C.C. [Tufts Univ., Medford, MA (United States)
1996-12-31T23:59:59.000Z
This article presents a comparative thermomechanical analysis of classical versus the new scan welding methods, that have been recently developed to achieve simultaneous control of multiple weld quality features. Unlike conventional welding with a concentrated heat source in sequential motion, the scan welding torch reciprocates rapidly on dynamic trajectories, and its power is modulated in-process, to provide a regulated heat input distribution on the entire weld surface. The new process was modeled by a real-time analytical, lumped model, consisting of a composite heat source description, double-cell circulation in the weld puddle, dynamic solid conduction and estimation of the mechanical strength of the joint. The process is computationally and experimentally shown to generate a smooth and uniform temperature field, and to deposit the full length of the weld bead simultaneously at a controlled solidification rate. The observed interlacing of grains on the bead interface and the regulated material microstructure yield improved tensile joint strength. The model can be used for design of a closed-loop thermal controller, using temperature feedback from an infrared pyrometer and model-referenced parameter identification.
Nuclear Systems Modeling, Simulation & Validation | ORNL
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Experiments for foam model development and validation.
Bourdon, Christopher Jay; Cote, Raymond O.; Moffat, Harry K.; Grillet, Anne Mary; Mahoney, James F. (Honeywell Federal Manufacturing and Technologies, Kansas City Plant, Kansas City, MO); Russick, Edward Mark; Adolf, Douglas Brian; Rao, Rekha Ranjana; Thompson, Kyle Richard; Kraynik, Andrew Michael; Castaneda, Jaime N.; Brotherton, Christopher M.; Mondy, Lisa Ann; Gorby, Allen D.
2008-09-01T23:59:59.000Z
A series of experiments has been performed to allow observation of the foaming process and the collection of temperature, rise rate, and microstructural data. Microfocus video is used in conjunction with particle image velocimetry (PIV) to elucidate the boundary condition at the wall. Rheology, reaction kinetics and density measurements complement the flow visualization. X-ray computed tomography (CT) is used to examine the cured foams to determine density gradients. These data provide input to a continuum level finite element model of the blowing process.
Validation of DWPF MOG dynamics model -- Phase 1
Choi, A.S.
1996-09-23T23:59:59.000Z
The report documents the results of a study to validate the DWPF melter off-gas system dynamics model using the data collected during the Waste Qualification Runs in 1995. The study consisted of: (1) calibration of the model using one set of melter idling data, (2) validation of the calibrated model using three sets of steady feeding and one set of transient data, and (3) application of the validated model to simulate the melter overfeeding incident which took place on 7/5.95. All the controller tuning constants and control logic used in the validated model are identical to those used in the DCS in 1995. However, the model does not reflect any design and/or operational changes made in 1996 to alleviate the glass pouring problem. Based on the results of the overfeeding simulation, it is concluded that the actual feed rates during that incident were about 2.75 times the indicated readings and that the peak concentration of combustible gases remained below 15% of the lower flammable limit during the entire one-hour duration.
Validation and Calibration in ACE Models: An Investigation on the CATS model.
Tesfatsion, Leigh
Validation and Calibration in ACE Models: An Investigation on the CATS model. Carlo Bianchi deal with some validation (and a ...rst calibration) experiments on the CATS model proposed whether the simulation model is an acceptable representation of the real system are available (Sar- gent
Material model library for explicit numerical codes
Hofmann, R.; Dial, B.W.
1982-08-01T23:59:59.000Z
A material model logic structure has been developed which is useful for most explicit finite-difference and explicit finite-element Lagrange computer codes. This structure has been implemented and tested in the STEALTH codes to provide an example for researchers who wish to implement it in generically similar codes. In parallel with these models, material parameter libraries have been created for the implemented models for materials which are often needed in DoD applications.
A numerical model of perturbation gas chromatography
DeBarro, Marc Joseph
1985-01-01T23:59:59.000Z
the polymer and the solvent. Flory (1965) extended his original model to account for the volume changes in the polymer phase. A further model was suggested by Sanchez and Lacombe (1978) based on s. lattice fluid theory. For the system examined in this work...
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Numerical studies of a simple Coulomb blockade model
Shao, Jianfeng
1991-01-01T23:59:59.000Z
NUMERICAL STUDIES OF A SIMPLE COULOMB BLOCKADE MODEL A Thesis by JIANFENG SHAO Submitted to the Office of Graduate Studies of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1991... Major Subject: Physics NUMERICAL STUDIES OF A SIMPLE COULOMB BLOCKADE MODEL A Thesis by JIANFENG SHAO Approved as to style and content by: Roland E, Allen (Chair of Committee) /, 1 r oseph H. R s ( Member) Chin B. Su (Member) Richard L...
Direct Methanol Fuel Cell Experimental and Model Validation Study
Wang, Chao-Yang
Direct Methanol Fuel Cell Experimental and Model Validation Study M. Mench, J. Scott, S. Thynell boundary Fuel cell performance Current density distribution measurements Conclusions #12;3 Method, flow rate, species inlet and fuel cell temperature, and humidity. Transparent polycarbonate windows
Modeling and Validating Hybrid Systems Using VDM and Mathematica
of the state changes discretely, the other part changes continuously over time. Typically, modern control interface and data animation. 1 Introduction Modern control applications are realized throughModeling and Validating Hybrid Systems Using VDM and Mathematica Bernhard K. Aichernig and Reinhold
Query Based UML Modeling Validation and Verification of the System Model and
Austin, Mark
1 Query Based UML Modeling Validation and Verification of the System Model and Behavior. UML/SysML was designed to provide simple but powerful constructs for modeling a wide range of systems for a Hydraulic Crane Denny Mathew ENPM 643 System Validation and Verification Instructor: Dr. Mark Austin Fall
Category:Numerical Modeling | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model, click here. Category:Conceptual ModelLists forMercury VaporTemplatespage? For
Experimentally validated finite element model of electrocaloric multilayer ceramic structures
Smith, N. A. S., E-mail: nadia.smith@npl.co.uk, E-mail: maciej.rokosz@npl.co.uk, E-mail: tatiana.correia@npl.co.uk; Correia, T. M., E-mail: nadia.smith@npl.co.uk, E-mail: maciej.rokosz@npl.co.uk, E-mail: tatiana.correia@npl.co.uk [National Physical Laboratory, Hampton Road, TW11 0LW Middlesex (United Kingdom); Rokosz, M. K., E-mail: nadia.smith@npl.co.uk, E-mail: maciej.rokosz@npl.co.uk, E-mail: tatiana.correia@npl.co.uk [National Physical Laboratory, Hampton Road, TW11 0LW Middlesex (United Kingdom); Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom)
2014-07-28T23:59:59.000Z
A novel finite element model to simulate the electrocaloric response of a multilayer ceramic capacitor (MLCC) under real environment and operational conditions has been developed. The two-dimensional transient conductive heat transfer model presented includes the electrocaloric effect as a source term, as well as accounting for radiative and convective effects. The model has been validated with experimental data obtained from the direct imaging of MLCC transient temperature variation under application of an electric field. The good agreement between simulated and experimental data, suggests that the novel experimental direct measurement methodology and the finite element model could be used to support the design of optimised electrocaloric units and operating conditions.
Validation experiment of a numerically processed millimeter-wave interferometer in a laboratory
Kogi, Y., E-mail: kogi@fit.ac.jp; Higashi, T.; Matsukawa, S. [Department of Information Electronics, Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Mase, A. [Art, Science and Technology Center for Cooperative Research, Kyushu University, Kasuga, Fukuoka 816-0811 (Japan); Kohagura, J.; Yoshikawa, M. [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Nagayama, Y.; Kawahata, K. [National Institute for Fusion Science, Toki, Gifu 509-5202 (Japan); Kuwahara, D. [Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 (Japan)
2014-11-15T23:59:59.000Z
We propose a new interferometer system for density profile measurements. This system produces multiple measurement chords by a leaky-wave antenna driven by multiple frequency inputs. The proposed system was validated in laboratory evaluation experiments. We confirmed that the interferometer generates a clear image of a Teflon plate as well as the phase shift corresponding to the plate thickness. In another experiment, we confirmed that quasi-optical mirrors can produce multiple measurement chords; however, the finite spot size of the probe beam degrades the sharpness of the resulting image.
Foundation Heat Exchanger Model and Design Tool Development and Validation
Heat Exchangers for Residential Ground Source Heat Pump Systems - Numerical Modeling and Experimental. Fisher, J. Shonder, P. Im. 2010. Residential Ground Source Heat Pump Systems Utilizing Foundation Heat. Feasibility of foundation heat exchangers in ground source heat pump systems in the United States. ASHRAE
Numerical Models of Blackbody-Dominated GRBs
Cuesta-Martínez, Carlos F; Mimica, Petar; Thöne, Christina C; de Ugarte-Postigo, Antonio
2015-01-01T23:59:59.000Z
Blackbody-dominated (BBD) gamma-ray bursts (GRBs) are events characterized by the absence of a typical afterglow, long durations and the presence of a significant thermal component following the prompt gamma-ray emission. GRB 101225A (the `Christmas burst') is a prototype of this class. A plausible progenitor system for it, and for the BBD-GRBs, is the merger of a neutron star (NS) and a helium core of an evolved, massive star. Using relativistic hydrodynamic simulations we model the propagation of an ultrarelativistic jet through the enviroment created by such a merger and we compute the whole radiative signature, both thermal and non-thermal, of the jet dynamical evolution. We find that the thermal emission originates from the interaction between the jet and the hydrogen envelope ejected during the NS/He merger.
Diffusion and Dispersion Characterization of a Numerical Tsunami Model
Tolkova, Elena
and numerical model. This plan is currently under devel- opment at the NCTR and a proof of concept has been-computed database of unit source solutions to determine the offshore tsunami waves. It then uses the MOST model (in nested grid mode) to propagate the offshore waves onshore for select regions. The critical factor
Numerical Modeling of Brain Dynamics in Traumatic Situations -Impulsive Translations
Burtscher, Martin
.S.A. Abstract We numerically model the brain dy- namics during and after impulsive head translations using brain injuries appear among boxers and shaken babies despite minimal rotations of their heads. Modeling head translations also helps understand the brain dynamics during head rotations about an arbitrary
Numerical modelling and analysis of a room temperature magnetic
Numerical modelling and analysis of a room temperature magnetic refrigeration system Thomas Frank and analysis of a room temperature magnetic refrigeration system Department: Fuel Cells and Solid State-dimensional mathematical model of an Active Magnetic Regenerator (AMR) system which is used for magnetic refrigeration
155: Numerical Models of Groundwater Flow and Transport
Sorek, Shaul
155: Numerical Models of Groundwater Flow and Transport EKKEHARD HOLZBECHER1 AND SHAUL SOREK2 1. #12;2402 GROUNDWATER Calibration as a task cannot be separated from the other tasks. Inverse modeling of the Negev, J. Blaustein Institutes for Desert Research, Sede Boker, Israel The article gives an introduction
Numerical study and validation of one swirling flame , Sren K. Kr, Chungen Yin
Berning, Torsten
Department of Energy Technology Aalborg University, Pontoppidanstræde 101, 9220 Aalborg, Denmark Abstract-7]. The reliable experimental data are used as model database in TNF and reference for modelling studies. Large
IN-DRIFT MICROBIAL COMMUNITIES MODEL VALIDATION CALCULATIONS
D.M. Jolley
2001-12-18T23:59:59.000Z
The objective and scope of this calculation is to create the appropriate parameter input for MING 1.0 (CSCI 30018 V1.0, CRWMS M&O 1998b) that will allow the testing of the results from the MING software code with both scientific measurements of microbial populations at the site and laboratory and with natural analogs to the site. This set of calculations provides results that will be used in model validation for the ''In-Drift Microbial Communities'' model (CRWMS M&O 2000) which is part of the Engineered Barrier System Department (EBS) process modeling effort that eventually will feed future Total System Performance Assessment (TSPA) models. This calculation is being produced to replace MING model validation output that is effected by the supersession of DTN M09909SPAMINGl.003 using its replacement DTN M00106SPAIDMO 1.034 so that the calculations currently found in the ''In-Drift Microbial Communities'' AMR (CRWMS M&O 2000) will be brought up to date. This set of calculations replaces the calculations contained in sections 6.7.2, 6.7.3 and Attachment I of CRWMS M&O (2000) As all of these calculations are created explicitly for model validation, the data qualification status of all inputs can be considered corroborative in accordance with AP-3.15Q. This work activity has been evaluated in accordance with the AP-2.21 procedure, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities'', and is subject to QA controls (BSC 2001). The calculation is developed in accordance with the AP-3.12 procedure, Calculations, and prepared in accordance with the ''Technical Work Plan For EBS Department Modeling FY 01 Work Activities'' (BSC 200 1) which includes controls for the management of electronic data.
NUMERICAL VERIFICATION OF THE RELAP-7 CORE CHANNEL SINGLE-PHASE MODEL
Haihua Zhao; Ling Zou; Hongbin Zhang; Richard Martineau
2014-06-01T23:59:59.000Z
The RELAP-7 code is the next generation of nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). All the physics in RELAP-7 are fully coupled and the errors resulted from the traditional operator-splitting approach are eliminated. By using 2nd order methods in both time and space and eliminating operator-splitting errors, the numerical error of RELAP-7 can be minimized. Numerical verification is the process to verify the orders of numerical methods. It is an important part of modern verification and validation process. The core channel component in RELAP-7 is designed to simulate coolant flow as well as the conjugated heat transfer between coolant flow and the fuel rod. A special treatment at fuel centerline to avoid numerical singularity for the cylindrical heat conduction in the continuous finite element mesh is discussed. One steady state test case and one fast power up transient test case are utilized for the verification of the core channel model with single-phase flow. Analytical solution for the fuel pin temperature and figures of merit such as peak clad temperature and peak fuel temperature are used to define numerical errors. These cases prove that the mass and energy are well conserved and 2nd order convergence rates for both time and space are achieved in the core channel model.
Egorov, I., E-mail: egoris@tpu.ru [Institute of High Technology Physics, Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028 (Russian Federation)
2014-06-15T23:59:59.000Z
This paper describes the development of a computation model of a pulsed voltage generator for a repetitive electron accelerator. The model is based on a principle circuit of the generator, supplemented with the parasitics elements of the construction. Verification of the principle model was achieved by comparison of simulation with experimental results, where reasonable agreement was demonstrated for a wide range of generator load resistance.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire3627 Federal RegisterImplementation andNumerical simulations
Robust design and model validation of nonlinear compliant micromechanisms.
Howell, Larry L. (Brigham Young University, Provo, UT); Baker, Michael Sean; Wittwer, Jonathan W. (Brigham Young University, Provo, UT)
2005-02-01T23:59:59.000Z
Although the use of compliance or elastic flexibility in microelectromechanical systems (MEMS) helps eliminate friction, wear, and backlash, compliant MEMS are known to be sensitive to variations in material properties and feature geometry, resulting in large uncertainties in performance. This paper proposes an approach for design stage uncertainty analysis, model validation, and robust optimization of nonlinear MEMS to account for critical process uncertainties including residual stress, layer thicknesses, edge bias, and material stiffness. A fully compliant bistable micromechanism (FCBM) is used as an example, demonstrating that the approach can be used to handle complex devices involving nonlinear finite element models. The general shape of the force-displacement curve is validated by comparing the uncertainty predictions to measurements obtained from in situ force gauges. A robust design is presented, where simulations show that the estimated force variation at the point of interest may be reduced from {+-}47 {micro}N to {+-}3 {micro}N. The reduced sensitivity to process variations is experimentally validated by measuring the second stable position at multiple locations on a wafer.
Friction versus dilation revisited: Insights from theoretical and numerical models
Einat, Aharonov
Friction versus dilation revisited: Insights from theoretical and numerical models N. Makedonska,1 controlled by the frictional strength of the fault gouge, a granular layer that accumulates between the fault friction coefficient) of such granular layers is the systems resistance to dilation, a byprocess
Numerical Modeling of the 2011 Tohoku Earthquake Tsunami
Frandsen, Jannette B.
Evolution of Ocean WAVEs) to reconstruct the tsunami across the Pacific and its transformation aroundNumerical Modeling of the 2011 Tohoku Earthquake Tsunami Yoshiki Yamazaki Post-doctoral Research 2011 Tohoku earthquake (Mw 9.0) generated a massive tsunami devastated the entire Pacific coast
Department of Numerical Analysis Modeling the Austenite Ferrite
Vuik, Kees
Department of Numerical Analysis Modeling the Austenite Ferrite Transformation by Cellular Ferrite Transformation by Cellular Automaton Improving Interface Stability Master of Science Thesis. Computational Materials Science 48.3 (2010): 692-699] for the austenite to ferrite transformation in low
Direct Numerical Simulations and Modeling of Jets in Crossflow
Mahesh, Krishnan
Direct Numerical Simulations and Modeling of Jets in Crossflow A THESIS SUBMITTED TO THE FACULTY. i #12;To my parents and my grandparents, and to Ramnath ii #12;Abstract Jets in crossflow are used to study the different aspects of round jets in a crossflow. The first problem studies
Validation of thermal models for a prototypical MEMS thermal actuator.
Gallis, Michail A.; Torczynski, John Robert; Piekos, Edward Stanley; Serrano, Justin Raymond; Gorby, Allen D.; Phinney, Leslie Mary
2008-09-01T23:59:59.000Z
This report documents technical work performed to complete the ASC Level 2 Milestone 2841: validation of thermal models for a prototypical MEMS thermal actuator. This effort requires completion of the following task: the comparison between calculated and measured temperature profiles of a heated stationary microbeam in air. Such heated microbeams are prototypical structures in virtually all electrically driven microscale thermal actuators. This task is divided into four major subtasks. (1) Perform validation experiments on prototypical heated stationary microbeams in which material properties such as thermal conductivity and electrical resistivity are measured if not known and temperature profiles along the beams are measured as a function of electrical power and gas pressure. (2) Develop a noncontinuum gas-phase heat-transfer model for typical MEMS situations including effects such as temperature discontinuities at gas-solid interfaces across which heat is flowing, and incorporate this model into the ASC FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (3) Develop a noncontinuum solid-phase heat transfer model for typical MEMS situations including an effective thermal conductivity that depends on device geometry and grain size, and incorporate this model into the FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (4) Perform combined gas-solid heat-transfer simulations using Calore with these models for the experimentally investigated devices, and compare simulation and experimental temperature profiles to assess model accuracy. These subtasks have been completed successfully, thereby completing the milestone task. Model and experimental temperature profiles are found to be in reasonable agreement for all cases examined. Modest systematic differences appear to be related to uncertainties in the geometric dimensions of the test structures and in the thermal conductivity of the polycrystalline silicon test structures, as well as uncontrolled nonuniform changes in this quantity over time and during operation.
Numerical Verification and Experimental Validation of Sliding Mode Control Design for
Kearfott, R. Baker
-temperature solid oxide fuel cell systems (SOFC sys- tems) can be described mainly by their thermal, fluidic Thermal SOFC Models Andreas Rauh, Luise Senkel, Thomas D¨otschel , Harald Aschemann Chair of Mechatronics@inf.uni-due.de Abstract The design of reliable and robust control strategies for the automatized operation of SOFC systems
Description and validation of ERAD: An atmospheric dispersion model for high explosive detonations
Boughton, B.A.; DeLaurentis, J.M.
1992-10-01T23:59:59.000Z
The Explosive Release Atmospheric Dispersion (ERAD) model is a three-dimensional numerical simulation of turbulent atmospheric transport and diffusion. An integral plume rise technique is used to provide a description of the physical and thermodynamic properties of the cloud of warm gases formed when the explosive detonates. Particle dispersion is treated as a stochastic process which is simulated using a discrete time Lagrangian Monte Carlo method. The stochastic process approach permits a more fundamental treatment of buoyancy effects, calm winds and spatial variations in meteorological conditions. Computational requirements of the three-dimensional simulation are substantially reduced by using a conceptualization in which each Monte Carlo particle represents a small puff that spreads according to a Gaussian law in the horizontal directions. ERAD was evaluated against dosage and deposition measurements obtained during Operation Roller Coaster. The predicted contour areas average within about 50% of the observations. The validation results confirm the model`s representation of the physical processes.
Analytical thermal model validation for Cassini radioisotope thermoelectric generator
Lin, E.I. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.
1997-12-31T23:59:59.000Z
The Saturn-bound Cassini spacecraft is designed to rely, without precedent, on the waste heat from its three radioisotope thermoelectric generators (RTGs) to warm the propulsion module subsystem, and the RTG end dome temperature is a key determining factor of the amount of waste heat delivered. A previously validated SINDA thermal model of the RTG was the sole guide to understanding its complex thermal behavior, but displayed large discrepancies against some initial thermal development test data. A careful revalidation effort led to significant modifications and adjustments of the model, which result in a doubling of the radiative heat transfer from the heat source support assemblies to the end domes and bring up the end dome and flange temperature predictions to within 2 C of the pertinent test data. The increased inboard end dome temperature has a considerable impact on thermal control of the spacecraft central body. The validation process offers an example of physically-driven analytical model calibration with test data from not only an electrical simulator but also a nuclear-fueled flight unit, and has established the end dome temperatures of a flight RTG where no in-flight or ground-test data existed before.
Model Based Test Generation for Microprocessor Architecture Validation
Minnesota, University of
, Minneapolis, MN 55455 CESCA, Virginia Tech, Blacksburg, VA 24061 Validation Technology, Intel Corporation
On numerical considerations for modeling reactive astrophysical shocks
Papatheodore, Thomas L.; Messer, O. E. Bronson, E-mail: tpapathe@utk.edu, E-mail: bronson@ornl.gov [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States)
2014-02-10T23:59:59.000Z
Simulating detonations in astrophysical environments is often complicated by numerical approximations to shock structure. A common prescription to ensure correct detonation speeds and associated quantities is to prohibit burning inside the numerically broadened shock. We have performed a series of simulations to verify the efficacy of this approximation and to understand how resolution and dimensionality might affect its use. Our results show that in one dimension, prohibiting burning in the shock is important wherever the carbon burning length is not resolved, in keeping with the results of Fryxell et al. In two dimensions, we find that the prohibition of shock burning effectively inhibits the development of cellular structure for all but the most highly resolved cases. We discuss the possible impacts this outcome may have on sub-grid models and detonation propagation in models of Type Ia supernovae, including potential impacts on observables.
Refined numerical models for multidimensional Type Ia supernova simulations
Reinecke, M; Niemeyer, J C
2002-01-01T23:59:59.000Z
Following up on earlier work on this topic (Reinecke et al. 1999, A&A 347, pp. 724 and 739), we present an improved set of numerical models for simulations of white dwarfs exploding as Type Ia supernovae (SNe Ia). Two-dimensional simulations were used to test the reliability and numerical robustness of these algorithms; the results indicate that integral quantities like the total energy release are insensitive to changes of the grid resolution (above a certain threshold), which was not the case for our former code. The models were further enhanced to allow fully three-dimensional simulations of SNe Ia. A direct comparison of a 2D and a 3D calculation with identical initial conditions shows that the explosion is considerably more energetic in three dimensions; this is most likely caused by the assumption of axisymmetry in 2D, which inhibits the growth of flame instabilities in the azimuthal direction and thereby decreases the flame surface.
Refined numerical models for multidimensional Type Ia supernova simulations
M. Reinecke; W. Hillebrandt; J. C. Niemeyer
2001-11-26T23:59:59.000Z
Following up on earlier work on this topic (Reinecke et al. 1999, A&A 347, pp. 724 and 739), we present an improved set of numerical models for simulations of white dwarfs exploding as Type Ia supernovae (SNe Ia). Two-dimensional simulations were used to test the reliability and numerical robustness of these algorithms; the results indicate that integral quantities like the total energy release are insensitive to changes of the grid resolution (above a certain threshold), which was not the case for our former code. The models were further enhanced to allow fully three-dimensional simulations of SNe Ia. A direct comparison of a 2D and a 3D calculation with identical initial conditions shows that the explosion is considerably more energetic in three dimensions; this is most likely caused by the assumption of axisymmetry in 2D, which inhibits the growth of flame instabilities in the azimuthal direction and thereby decreases the flame surface.
Validation of reduced kinetic models for simulations of non-steady combustion processes
Ivanov, M F; Liberman, M A; Smygalina, A E
2013-01-01T23:59:59.000Z
In the present work we compare reliability of several most widely used reduced detailed chemical kinetic schemes for hydrogen-air and hydrogen-oxygen combustible mixtures. The validation of the schemes includes detailed analysis of 0D and 1D calculations and comparison with experimental databases containing data on induction time, equilibrium temperature, composition of the combustion products, laminar flame speed and the flame front thickness at different pressures. 1D calculations are carried out using the full gasdynamical system for compressible viscous thermal conductive multicomponent mixture. The proper choice of chemical kinetics models is essential for obtaining reliable quantitative and qualitative insight into combustion phenomena such as flame acceleration and stability, ignition, transition from deflagration-to-detonation (DDT) using a multiscale numerical modeling.
ASSIMILATION OF DOPPLER RADAR DATA INTO NUMERICAL WEATHER MODELS
Chiswell, S.; Buckley, R.
2009-01-15T23:59:59.000Z
During the year 2008, the United States National Weather Service (NWS) completed an eight fold increase in sampling capability for weather radars to 250 m resolution. This increase is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current NWS operational model domains utilize grid spacing an order of magnitude larger than the radar data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of radar reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution was investigated under a Laboratory Directed Research and Development (LDRD) 'quick hit' grant to determine the impact of improved data resolution on model predictions with specific initial proof of concept application to daily Savannah River Site operations and emergency response. Development of software to process NWS radar reflectivity and radial velocity data was undertaken for assimilation of observations into numerical models. Data values within the radar data volume undergo automated quality control (QC) analysis routines developed in support of this project to eliminate empty/missing data points, decrease anomalous propagation values, and determine error thresholds by utilizing the calculated variances among data values. The Weather Research and Forecasting model (WRF) three dimensional variational data assimilation package (WRF-3DVAR) was used to incorporate the QC'ed radar data into input and boundary conditions. The lack of observational data in the vicinity of SRS available to NWS operational models signifies an important data void where radar observations can provide significant input. These observations greatly enhance the knowledge of storm structures and the environmental conditions which influence their development. As the increase in computational power and availability has made higher resolution real-time model simulations possible, the need to obtain observations to both initialize numerical models and verify their output has become increasingly important. The assimilation of high resolution radar observations therefore provides a vital component in the development and utility of numerical model forecasts for both weather forecasting and contaminant transport, including future opportunities to improve wet deposition computations explicitly.
Mathematical and Numerical Analyses of Peridynamics for Multiscale Materials Modeling
Du, Qiang
2014-11-12T23:59:59.000Z
The rational design of materials, the development of accurate and efficient material simulation algorithms, and the determination of the response of materials to environments and loads occurring in practice all require an understanding of mechanics at disparate spatial and temporal scales. The project addresses mathematical and numerical analyses for material problems for which relevant scales range from those usually treated by molecular dynamics all the way up to those most often treated by classical elasticity. The prevalent approach towards developing a multiscale material model couples two or more well known models, e.g., molecular dynamics and classical elasticity, each of which is useful at a different scale, creating a multiscale multi-model. However, the challenges behind such a coupling are formidable and largely arise because the atomistic and continuum models employ nonlocal and local models of force, respectively. The project focuses on a multiscale analysis of the peridynamics materials model. Peridynamics can be used as a transition between molecular dynamics and classical elasticity so that the difficulties encountered when directly coupling those two models are mitigated. In addition, in some situations, peridynamics can be used all by itself as a material model that accurately and efficiently captures the behavior of materials over a wide range of spatial and temporal scales. Peridynamics is well suited to these purposes because it employs a nonlocal model of force, analogous to that of molecular dynamics; furthermore, at sufficiently large length scales and assuming smooth deformation, peridynamics can be approximated by classical elasticity. The project will extend the emerging mathematical and numerical analysis of peridynamics. One goal is to develop a peridynamics-enabled multiscale multi-model that potentially provides a new and more extensive mathematical basis for coupling classical elasticity and molecular dynamics, thus enabling next generation atomistic-to-continuum multiscale simulations. In addition, a rigorous study of nite element discretizations of peridynamics will be considered. Using the fact that peridynamics is spatially derivative free, we will also characterize the space of admissible peridynamic solutions and carry out systematic analyses of the models, in particular rigorously showing how peridynamics encompasses fracture and other failure phenomena. Additional aspects of the project include the mathematical and numerical analysis of peridynamics applied to stochastic peridynamics models. In summary, the project will make feasible mathematically consistent multiscale models for the analysis and design of advanced materials.
Seebold, J.G. [Chevron Research and Technology Co., Richmond, CA (United States); Kee, R.J.; Lutz, A.J. [Sandia National Labs., Albuquerque, NM (United States); Pitz, W.J.; Westbrook, C.K. [Lawrence Livermore National Lab., CA (United States); Senkan, S. [California Univ., Los Angeles, CA (United States)
1992-09-01T23:59:59.000Z
A collaborative research program initiated to study the emissions of a wide variety of chemical species from stationary combustion systems. These product species have been included in the Clean Air act legislation and their emissions must be rigidly controlled, but there is a need for much better understanding of the physical and chemical mechanisms that produce and consume them. We are using numerical modeling study the chemical reactions and fluid mechanical factors that occur in industrial processes: we are examining systems including premixed and diffusion flames, stirred reactors and plug flow reactors in these modeling studies to establish the major factors leading to emissions of these chemicals. In addition, we are applying advanced laser diagnostic techniques to validate the model predictions and to study the possibilities of developing sophisticated sensors to detect emissions of undesirable species in real time. This paper will discuss the organization of this collaborative effort and its results to date.
Bammann, Douglas J.; Johnson, G. C. (University of California, Berkeley, CA); Marin, Esteban B.; Regueiro, Richard A. (University of Colorado, Boulder, CO)
2006-01-01T23:59:59.000Z
In this report we present the formulation of the physically-based Evolving Microstructural Model of Inelasticity (EMMI) . The specific version of the model treated here describes the plasticity and isotropic damage of metals as being currently applied to model the ductile failure process in structural components of the W80 program . The formulation of the EMMI constitutive equations is framed in the context of the large deformation kinematics of solids and the thermodynamics of internal state variables . This formulation is focused first on developing the plasticity equations in both the relaxed (unloaded) and current configurations. The equations in the current configuration, expressed in non-dimensional form, are used to devise the identification procedure for the plasticity parameters. The model is then extended to include a porosity-based isotropic damage state variable to describe the progressive deterioration of the strength and mechanical properties of metals induced by deformation . The numerical treatment of these coupled plasticity-damage constitutive equations is explained in detail. A number of examples are solved to validate the numerical implementation of the model.
Numerical Modeling of Charged Black Holes with Massive Dilaton
T. L. Boyadjiev; P. P. Fiziev
2003-11-28T23:59:59.000Z
In this paper the static, spherically symmetric and electrically charged black hole solutions in Einstein-Born-Infeld gravity with massive dilaton are investigated numerically. The Continuous Analog of Newton Method (CANM) is used to solve the corresponding nonlinear multipoint boundary value problems (BVPs). The linearized BVPs are solved numerically by means of collocation scheme of fourth order. A special class of solutions are the extremal ones. We show that the extremal horizons within the framework of the model satisfy some nonlinear system of algebraic equations. Depending on the charge $q$ and dilaton mass $\\gamma$, the black holes can have no more than three horizons. This allows us to construct some Hermite polynomial of third order. Its real roots describe the number, the type and other characteristics of the horizons.
On Numerical Considerations for Modeling Reactive Astrophysical Shocks
Papatheodore, Thomas L [ORNL] [ORNL; Messer, Bronson [ORNL] [ORNL
2014-01-01T23:59:59.000Z
Simulating detonations in astrophysical environments is often complicated by numerical approximations to shock structure. A common prescription to ensure correct detonation speeds (and associated quantities) is to prohibit burning inside the numerically broadened shock (Fryxell et al. 1989). We have performed a series of simulations to verify the efficacy of this approximation and to understand how resolution and dimensionality might affect its use. Our results show that, in one dimension, prohibiting burning in the shock is important wherever the carbon burning length is not resolved, in keeping with the results of Fryxell et al. (1989). In two dimensions, we find that the prohibition of shock burning effectively inhibits the development of cellular structure for all but the most highly-resolved cases. We discuss the possible impacts this outcome may have on sub-grid models and detonation propagation in Type Ia supernovae.
Fast, J.D.; O'Steen, B.L.
1992-01-01T23:59:59.000Z
An important aspect of the US Department of Energy's Atmospheric Studies in Complex Terrain (ASCOT) program is the development and evaluation of numerical models that predict transport and diffusion of pollutants in complex terrain. Operational mesoscale modeling of the transport of pollutants in complex terrain will become increasingly practical as computational costs decrease and additional data from high-resolution remote sensing instrumentation networks become available during the 1990s. Four-dimensional data assimilation (4DDA) techniques are receiving a great deal of attention recently not only to improve the initial conditions of mesoscale forecast models, but to create high-quality four-dimensional mesoscale analysis fields that can be used as input to air-quality models. In this study, a four-dimensional data assimilation technique based on Newtonian relaxation is incorporated into the Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) and evaluated using data taken from one experiment of the 1991 ASCOT field study along the front range of the Rockies in Colorado. The main objective of this study is to compare the observed surface concentrations with those predicted by a Lagrangian particle dispersion model and to demonstrate the effect of data assimilation on the simulated plume. In contrast to pervious studies in which the smallest horizontal grid spacing was 10 km (Stauffer and Seaman, 1991) and 8 km (Yamada and Hermi, 1991), data assimilation is applied in this study to domains with a horizontal grid spacing as small as 1 km.
Fast, J.D.; O`Steen, B.L.
1992-11-01T23:59:59.000Z
An important aspect of the US Department of Energy`s Atmospheric Studies in Complex Terrain (ASCOT) program is the development and evaluation of numerical models that predict transport and diffusion of pollutants in complex terrain. Operational mesoscale modeling of the transport of pollutants in complex terrain will become increasingly practical as computational costs decrease and additional data from high-resolution remote sensing instrumentation networks become available during the 1990s. Four-dimensional data assimilation (4DDA) techniques are receiving a great deal of attention recently not only to improve the initial conditions of mesoscale forecast models, but to create high-quality four-dimensional mesoscale analysis fields that can be used as input to air-quality models. In this study, a four-dimensional data assimilation technique based on Newtonian relaxation is incorporated into the Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) and evaluated using data taken from one experiment of the 1991 ASCOT field study along the front range of the Rockies in Colorado. The main objective of this study is to compare the observed surface concentrations with those predicted by a Lagrangian particle dispersion model and to demonstrate the effect of data assimilation on the simulated plume. In contrast to pervious studies in which the smallest horizontal grid spacing was 10 km (Stauffer and Seaman, 1991) and 8 km (Yamada and Hermi, 1991), data assimilation is applied in this study to domains with a horizontal grid spacing as small as 1 km.
De Castro, Carlos Armando
2011-01-01T23:59:59.000Z
In this paper is developed a simple mathematical model of transient heat transfer under soil with plastic mulch in order to determine with numerical studies the influence of different plastic mulches on the soil temperature and the evolutions of temperatures at different depths with time. The governing differential equations are solved by a Galerkin Finite Element Model, taking into account the nonlinearities due to radiative heat exchange between the soil surface, the plastic mulch and the atmosphere. The model was validated experimentally giving good approximation of the model to the measured data. Simulations were run with the validated model in order to determine the optimal combination of mulch optical properties to maximize the soil temperature with a Taguchi's analysis, proving that the material most used nowadays in Colombia is not the optimal and giving quantitative results of the properties the optimal mulch must possess.
Modeling of a Foamed Emulsion Bioreactor: I. Model Development and Experimental Validation
ARTICLE Modeling of a Foamed Emulsion Bioreactor: I. Model Development and Experimental Validation, a new type of bioreactor for air pollution control referred to as the foamed emulsion bior- eactor (FEBR Introduction Biofilters and biotrickling filters are the most widely used bioreactors for treating low levels
An approach to model validation and model-based prediction -- polyurethane foam case study.
Dowding, Kevin J.; Rutherford, Brian Milne
2003-07-01T23:59:59.000Z
Enhanced software methodology and improved computing hardware have advanced the state of simulation technology to a point where large physics-based codes can be a major contributor in many systems analyses. This shift toward the use of computational methods has brought with it new research challenges in a number of areas including characterization of uncertainty, model validation, and the analysis of computer output. It is these challenges that have motivated the work described in this report. Approaches to and methods for model validation and (model-based) prediction have been developed recently in the engineering, mathematics and statistical literatures. In this report we have provided a fairly detailed account of one approach to model validation and prediction applied to an analysis investigating thermal decomposition of polyurethane foam. A model simulates the evolution of the foam in a high temperature environment as it transforms from a solid to a gas phase. The available modeling and experimental results serve as data for a case study focusing our model validation and prediction developmental efforts on this specific thermal application. We discuss several elements of the ''philosophy'' behind the validation and prediction approach: (1) We view the validation process as an activity applying to the use of a specific computational model for a specific application. We do acknowledge, however, that an important part of the overall development of a computational simulation initiative is the feedback provided to model developers and analysts associated with the application. (2) We utilize information obtained for the calibration of model parameters to estimate the parameters and quantify uncertainty in the estimates. We rely, however, on validation data (or data from similar analyses) to measure the variability that contributes to the uncertainty in predictions for specific systems or units (unit-to-unit variability). (3) We perform statistical analyses and hypothesis tests as a part of the validation step to provide feedback to analysts and modelers. Decisions on how to proceed in making model-based predictions are made based on these analyses together with the application requirements. Updating modifying and understanding the boundaries associated with the model are also assisted through this feedback. (4) We include a ''model supplement term'' when model problems are indicated. This term provides a (bias) correction to the model so that it will better match the experimental results and more accurately account for uncertainty. Presumably, as the models continue to develop and are used for future applications, the causes for these apparent biases will be identified and the need for this supplementary modeling will diminish. (5) We use a response-modeling approach for our predictions that allows for general types of prediction and for assessment of prediction uncertainty. This approach is demonstrated through a case study supporting the assessment of a weapons response when subjected to a hydrocarbon fuel fire. The foam decomposition model provides an important element of the response of a weapon system in this abnormal thermal environment. Rigid foam is used to encapsulate critical components in the weapon system providing the needed mechanical support as well as thermal isolation. Because the foam begins to decompose at temperatures above 250 C, modeling the decomposition is critical to assessing a weapons response. In the validation analysis it is indicated that the model tends to ''exaggerate'' the effect of temperature changes when compared to the experimental results. The data, however, are too few and to restricted in terms of experimental design to make confident statements regarding modeling problems. For illustration, we assume these indications are correct and compensate for this apparent bias by constructing a model supplement term for use in the model-based predictions. Several hypothetical prediction problems are created and addressed. Hypothetical problems are used because no guidance was provided concern
Documentation of Hybrid Hydride Model for Incorporation into Moose-Bison and Validation Strategy.
Weck, Philippe F; Tikare, Veena; Schultz, Peter Andrew; Clark, B (SNL); Mitchell, J (SNL); Glazoff, Michael V.; Homer, Eric R.
2014-10-01T23:59:59.000Z
This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride ?-ZrH{sub 1.5} precipitation in the cladding of used nuclear fuels that may occur during long-term dry storage. While the Zr-based claddings are manufactured free of any hydrogen, they absorb hydrogen during service, in the reactor by a process commonly termed ‘hydrogen pick-up’. The precipitation and growth of zirconium hydrides during dry storage is one of the most likely fuel rod integrity failure mechanisms either by embrittlement or delayed hydride cracking of the cladding (Hanson et al., 2011). While the phenomenon is well documented and identified as a potential key failure mechanism during long-term dry storage (Birk et al., 2012 and NUREG/CR-7116), the ability to actually predict the formation of hydrides is poor. The model being documented in this work is a computational capability for the prediction of hydride formation in different claddings of used nuclear fuels. This work supports the Used Fuel Disposition Research and Development Campaign in assessing the structural engineering performance of the cladding during and after long-term dry storage. In this work, a model to numerically simulate hydride precipitation at the microstructural scale, in a wide variety of Zr-based claddings, under dry-storage conditions is being developed. It will be used to aid in the evaluation of the mechanical integrity of used fuel rods during dry storage and transportation by providing the structural conditions from the microstructural scale to the continuum scale to engineering component scale models to predict if the used fuel rods will perform without failure under normal and off-normal conditions. The microstructure, especially, the hydride structure is thought to be a primary determinant of cladding failure, thus this component of UFD’s storage and transportation analysis program is critical. The model development, application and validation of the model are documented and the limitations of the current model are discussed. The model has been shown to simulate hydride precipitation in Zircaloy-4 cladding with correct morphology, thermodynamics and kinetics. An unexpected insight obtained from simulations hydride formation in Zircaloy-4 is that small (sub-micron) precipitates need to order themselves to form the larger hydrides typically described as radially-reoriented precipitates. A limitation of this model is that it does not currently solve the stress state that forms dynamically in the precipitate or matrix surrounding the precipitate. A method to overcome the limitations is suggested and described in detail. The necessary experiments to provide key materials physics and to validate the model are also recommended.
Temperature distributions in the laser-heated diamond anvil cell from 3-D numerical modeling
Rainey, E. S. G.; Kavner, A. [Department of Earth and Space Sciences, University of California, Los Angeles, California 90095 (United States); Hernlund, J. W. [Department of Earth and Planetary Science, University of California, Berkeley, California 94720 (United States); Earth-Life Science Institute, Megoro, Tokyo 152-8551 (Japan)
2013-11-28T23:59:59.000Z
We present TempDAC, a 3-D numerical model for calculating the steady-state temperature distribution for continuous wave laser-heated experiments in the diamond anvil cell. TempDAC solves the steady heat conduction equation in three dimensions over the sample chamber, gasket, and diamond anvils and includes material-, temperature-, and direction-dependent thermal conductivity, while allowing for flexible sample geometries, laser beam intensity profile, and laser absorption properties. The model has been validated against an axisymmetric analytic solution for the temperature distribution within a laser-heated sample. Example calculations illustrate the importance of considering heat flow in three dimensions for the laser-heated diamond anvil cell. In particular, we show that a “flat top” input laser beam profile does not lead to a more uniform temperature distribution or flatter temperature gradients than a wide Gaussian laser beam.
atmosphere model validation: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
predictability over eastern Australia in JJASON This research aims to improve intra Marshall, Andrew 3 Early validation analyses of atmospheric profiles from CiteSeer...
A Workflow for Parameter Calibration and and Model Validation in SST: Interim Report.
Pebay, Philippe Pierre; Wilke, Jeremiah J; Sargsyan, Khachik
2014-12-01T23:59:59.000Z
This brief report explains the method used for parameter calibration and model validation in SST/Macro and the set of tools and workflow developed for this purpose.
Model Validation at the 204-MW New Mexico Wind Energy Center
Muljadi, E.; Butterfield, C. P.; Ellis, A.; Mechenbier, J.; Hochheimer, J.; Young, R.; Miller, N.; Delmerico, R.; Zavadil, R.; Smith, J. C.
2006-06-01T23:59:59.000Z
Poster for WindPower 2006 held June 4-7, 2006, in Pittsburgh, PA, describing model validation at the 204-MW New Mexico Wind Energy Center.
Lee, Kenneth L.; Korellis, John S.; McFadden, Sam X.
2006-01-01T23:59:59.000Z
Experimental data for material plasticity and failure model calibration and validation were obtained from 304L stainless steel. Model calibration data were taken from smooth tension, notched tension, and compression tests. Model validation data were provided from experiments using thin-walled tube specimens subjected to path dependent combinations of internal pressure, extension, and torsion.
Pearce, Fred
2003-01-01T23:59:59.000Z
We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir
Progress report on LBL's numerical modeling studies on Cerro Prieto
Halfman-Dooley, S.E.; Lippman, M.J.; Bodvarsson, G.S.
1989-04-01T23:59:59.000Z
An exploitation model of the Cerro Prieto geothermal system is needed to assess the energy capacity of the field, estimate its productive lifetime and develop an optimal reservoir management plan. The model must consider the natural state (i.e., pre-exploitation) conditions of the system and be able to predict changes in the reservoir thermodynamic conditions (and fluid chemistry) in response to fluid production (and injection). This paper discusses the results of a three-dimensional numerical simulation of the natural state conditions of the Cerro Prieto field and compares computed and observed pressure and temperature/enthalpy changes for the 1973--1987 production period. 16 refs., 24 figs., 2 tabs.
An independent verification and validation of the Future Theater Level Model conceptual model
Hartley, D.S. III; Kruse, K.L.; Martellaro, A.J.; Packard, S.L.; Thomas, B. Jr.; Turley, V.K.
1994-08-01T23:59:59.000Z
This report describes the methodology and results of independent verification and validation performed on a combat model in its design stage. The combat model is the Future Theater Level Model (FTLM), under development by The Joint Staff/J-8. J-8 has undertaken its development to provide an analysis tool that addresses the uncertainties of combat more directly than previous models and yields more rapid study results. The methodology adopted for this verification and validation consisted of document analyses. Included were detailed examination of the FTLM design documents (at all stages of development), the FTLM Mission Needs Statement, and selected documentation for other theater level combat models. These documents were compared to assess the FTLM as to its design stage, its purpose as an analytical combat model, and its capabilities as specified in the Mission Needs Statement. The conceptual design passed those tests. The recommendations included specific modifications as well as a recommendation for continued development. The methodology is significant because independent verification and validation have not been previously reported as being performed on a combat model in its design stage. The results are significant because The Joint Staff/J-8 will be using the recommendations from this study in determining whether to proceed with develop of the model.
Bhaumik, Tirtharaj
2005-11-01T23:59:59.000Z
Understanding the physics of multiphase plumes and their simulation through numerical modeling has been an important area of research in recent times in the area of environmental fluid mechanics. The two renowned numerical modeling types...
A numerical model of aerosol scavenging: Part 1, Microphysics parameterization
Molenkamp, C.R.; Bradley, M.M.
1991-09-01T23:59:59.000Z
We have developed a three-dimensional numerical model (OCTET) to simulate the dynamics and microphysics of clouds and the transport, diffusion and precipitation scavenging of aerosol particles. In this paper we describe the cloud microphysics and scavenging parameterizations. The representation of cloud microphysics is a bulk- water parameterization which includes water vapor and five types of hydrometeors (cloud droplets, rain drops, ice crystals, snow, and graupel). A parallel parameterization represents the scavenging interactions between pollutant particles and hydrometeors including collection of particles because of condensation nucleation, Brownian and phoretic attachment, and inertial capture, resuspension because of evaporation and sublimation; and transfer interactions where particles collected by one type of hydrometeor are transferred to another type of freezing, melting, accretion, riming and autoconversion.
Validation and Application of the Room Model of the Modelica Buildings Library
LBNL-5932E Validation and Application of the Room Model of the Modelica Buildings Library Authors and Technologies Division September 2012 Presented at the 9th International Modelica Conference 2012 #12;DISCLAIMER of California. #12;Validation and Application of the Room Model of the Modelica Buildings Library Thierry
Experimental identification and validation of an electrochemical model of a Lithium-Ion Battery
Stefanopoulou, Anna
Experimental identification and validation of an electrochemical model of a Lithium-Ion Battery an experimental parameter iden- tification and validation for an electrochemical lithium-ion battery model. The identification procedure is based on experimental data collected from a 6.8 Ah lithium-ion battery during charge
Title: Modeling, Validation and Verification of Concurrent Behavior in the Panama Canal
Austin, Mark
ABSTRACT Title: Modeling, Validation and Verification of Concurrent Behavior in the Panama Canal Professor Mark Austin, Department of Civil and Environmental Engineering and Institute for Systems Research are reactive and concurrent in nature. The procedure to model a concurrent system and the procedure to validate
Adaptation and Validation of an Agent Model of Functional State and Performance for Individuals
Treur, Jan
functional state model to the individual and validation of the resulting model. First, human experiments have mostly qualitative theories from Psychology, but was not validated yet using human experiments been performed by taking a number of steps. First of all, an experiment with 31 human subjects has been
Peter Diener; Brajesh Gupt; Parampreet Singh
2014-05-16T23:59:59.000Z
A key result of isotropic loop quantum cosmology is the existence of a quantum bounce which occurs when the energy density of the matter field approaches a universal maximum close to the Planck density. Though the bounce has been exhibited in various matter models, due to severe computational challenges some important questions have so far remained unaddressed. These include the demonstration of the bounce for widely spread states, its detailed properties for the states when matter field probes regions close to the Planck volume and the reliability of the continuum effective spacetime description in general. In this manuscript we rigorously answer these questions using the Chimera numerical scheme for the isotropic spatially flat model sourced with a massless scalar field. We show that as expected from an exactly solvable model, the quantum bounce is a generic feature of states even with a very wide spread, and for those which bounce much closer to the Planck volume. We perform a detailed analysis of the departures from the effective description and find some expected, and some surprising results. At a coarse level of description, the effective dynamics can be regarded as a good approximation to the underlying quantum dynamics unless the states correspond to small scalar field momenta, in which case they bounce closer to the Planck volume, or are very widely spread. Quantifying the amount of discrepancy between the quantum and the effective dynamics, we find that the departure between them depends in a subtle and non-monotonic way on the field momentum and different fluctuations. Interestingly, the departures are generically found to be such that the effective dynamics overestimates the spacetime curvature, and underestimates the volume at the bounce.
Effective viscosity of active suspensions: Three-dimensional numerical modeling
Levan Jibuti; Walter Zimmermann; Salima Rafaï; Philippe Peyla
2014-12-10T23:59:59.000Z
A three-dimensional model is proposed for Chlamydomonas Reinhardtii swimming with a breaststroke-like beating of its two flagella. The model reveals unusual angular orbits of the active swimmer under a linear shear flow. Namely, the swimmer sustains orientation transiently across the flow when flagella plane is perpendicular to the shear plane, and amplify the shear-induced rotation along the flow. Such behavior is a result of the interplay between shear-induced deformation and swimmer's periodic beating motion that exerts internal torques on the torque-free swimmer. This particular behavior has some significant consequences on the rheological properties of the suspension that tends to confirm previous experimental results [Phys. Rev. Lett. 104, 098102 (2010)]. We calculated the intrinsic viscosity of the suspension with such isolated modeled microswimmers (dilute case) in shear flow using numerical simulations based on Rotne-Prager approximation. The results show an increased intrinsic viscosity for active swimmer suspensions in comparison to non-active ones in accordance with previous experimental measurements. A major enhancement of the active swimmer viscosity occurs due to the effectively extended shape of the deformable swimming cells. We also recover the experimentally observed shear thinning behavior.
Numerical Methods for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory
Zhihao Ge; Ruihua Li
2014-12-25T23:59:59.000Z
In the work, the numerical methods are designed for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory. The numerical methods are novel and effective to determine the critical transition temperature and approximate to the energy gap function of the above model. Finally, a numerical example confirming the theoretical results is presented.
Numerical Methods for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory
Zhihao Ge; Ruihua Li
2015-03-08T23:59:59.000Z
In the work, the numerical methods are designed for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory. The numerical methods are novel and effective to determine the critical transition temperature and approximate to the energy gap function of the above model. Finally, a numerical example confirming the theoretical results is presented.
NUMERICAL MODELING OF FLUID FLOW AND TIME-LAPSE ...
gabriela
Abstract. CO2 sequestration in the underground is a valid alternative approach for mitigat- ing the greenhouse effect. Nevertheless, very little is known about the
Development of a Hydraulic Manipulator Servoactuator Model: Simulation and Experimental Validation
Papadopoulos, Evangelos
Development of a Hydraulic Manipulator Servoactuator Model: Simulation and Experimental Validation Abstract In this paper, modelling and identification of a hydraulic servoactuator system is presented, leakage, and load dynamics. System parameters are identified based on a high-performance hydraulic
Some guidance on preparing validation plans for the DART Full System Models.
Gray, Genetha Anne; Hough, Patricia Diane; Hills, Richard Guy (Sandia National Laboratories, Albuquerque, NM)
2009-03-01T23:59:59.000Z
Planning is an important part of computational model verification and validation (V&V) and the requisite planning document is vital for effectively executing the plan. The document provides a means of communicating intent to the typically large group of people, from program management to analysts to test engineers, who must work together to complete the validation activities. This report provides guidelines for writing a validation plan. It describes the components of such a plan and includes important references and resources. While the initial target audience is the DART Full System Model teams in the nuclear weapons program, the guidelines are generally applicable to other modeling efforts. Our goal in writing this document is to provide a framework for consistency in validation plans across weapon systems, different types of models, and different scenarios. Specific details contained in any given validation plan will vary according to application requirements and available resources.
AI-Based Simulation: An Alternative to Numerical Simulation and Modeling
Mohaghegh, Shahab
: Numerical Modeling, Simulation, Artificial Intelligence, Data Min- ing, Reservoir Modeling, Reservoir data for brown fields. The run-time of AI-Based reservoir models that provide complete field responses Computational Fluid Dynamics (CFD) to Numer- ical Reservoir Simulation (NRS) most of the computational modeling
Walraven, Jeremy Allen; Blecke, Jill; Baker, Michael Sean; Clemens, Rebecca C.; Mitchell, John Anthony; Brake, Matthew Robert; Epp, David S.; Wittwer, Jonathan W.
2008-10-01T23:59:59.000Z
This report summarizes the functional, model validation, and technology readiness testing of the Sandia MEMS Passive Shock Sensor in FY08. Functional testing of a large number of revision 4 parts showed robust and consistent performance. Model validation testing helped tune the models to match data well and identified several areas for future investigation related to high frequency sensitivity and thermal effects. Finally, technology readiness testing demonstrated the integrated elements of the sensor under realistic environments.
Development and validation of instantaneous risk model in nuclear power plant's risk monitor
Wang, J.; Li, Y.; Wang, F.; Wang, J.; Hu, L. [Inst. of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China); School of Nuclear Science and Technology, Univ. of Science and Technology of China, Hefei, Anhui, 230031 (China)
2012-07-01T23:59:59.000Z
The instantaneous risk model is the fundament of calculation and analysis in a risk monitor. This study focused on the development and validation of an instantaneous risk model. Therefore the principles converting from the baseline risk model to the instantaneous risk model were studied and separated trains' failure modes modeling method was developed. The development and validation process in an operating nuclear power plant's risk monitor were also introduced. Correctness of instantaneous risk model and rationality of converting method were demonstrated by comparison with the result of baseline risk model. (authors)
Validation of a Model of a Resonant Optothermoacoustic Trace Gas Sensor
Minkoff, Susan E.
Validation of a Model of a Resonant Optothermoacoustic Trace Gas Sensor N. Petra1, J. Zweck1, S. E optothermoacoustic sensor is validated by comparison with experiments performed with 0.5% acetylene in nitrogen Optical Society of America OCIS codes: 300.6430, 300.6340. 1. Introduction Quartz-Enhanced Photo
Mishra, Prabhat
) design process. Many existing approaches employ a bottom-up approach to pipeline validation, where about the behavior of the pipelined ar- chitecture through ADL constructs, which allows a powerful topAutomatic Modeling and Validation of Pipeline Specifications driven by an Architecture Description
Representing Cloud Processing of Aerosol in Numerical Models
Mechem, D.B.; Kogan, Y.L.
2005-03-18T23:59:59.000Z
The satellite imagery in Figure 1 provides dramatic examples of how aerosol influences the cloud field. Aerosol from ship exhaust can serve as nucleation centers in otherwise cloud-free regions, forming ship tracks (top image), or can enhance the reflectance/albedo in already cloudy regions. This image is a demonstration of the first indirect effect, in which changes in aerosol modulate cloud droplet radius and concentration, which influences albedo. It is thought that, through the effects it has on precipitation (drizzle), aerosol can also affect the structure and persistence of planetary boundary layer (PBL) clouds. Regions of cellular convection, or open pockets of cloudiness (bottom image) are thought to be remnants of strongly drizzling PBL clouds. Pockets of Open Cloudiness (POCs) (Stevens et al. 2005) or Albrecht's ''rifts'' are low cloud fraction regions characterized by anomalously low aerosol concentrations, implying they result from precipitation. These features may in fact be a demonstration of the second indirect effect. To accurately represent these clouds in numerical models, we have to treat the coupled cloud-aerosol system. We present the following series of mesoscale and large eddy simulation (LES) experiments to evaluate the important aspects of treating the coupled cloud-aerosol problem. 1. Drizzling and nondrizzling simulations demonstrate the effect of drizzle on a mesoscale forecast off the California coast. 2. LES experiments with explicit (bin) microphysics gauge the relative importance of the shape of the aerosol spectrum on the 3D dynamics and cloud structure. 3. Idealized mesoscale model simulations evaluate the relative roles of various processes, sources, and sinks.
Thermodynamic Modeling and Numerical Simulation of Single-Shaft Microturbine Performance
Hao, X.; Zhang, G.; Zhou, J.; Chen, Y.
2006-01-01T23:59:59.000Z
's performance under off-design situations. The proposed model is validated by operational data of a commercially available micro- turbine from a reference. The result shows that the proposed mathematical model can preferably represent the quasi...
An efficient numerical terrestrial scheme (ENTS) for fast earth system modelling
Williamson, Mark
An efficient numerical terrestrial scheme (ENTS) for fast earth system modelling Mark Williamson Working Paper 83 #12;An efficient numerical terrestrial scheme (ENTS) for fast earth system modelling Mark for long time period simulations and large ensemble studies in Earth system models of intermediate
Numerical analysis of a model for Nickel-Iron alloy electrodeposition on rotating disk
Paris-Sud XI, Université de
Numerical analysis of a model for Nickel-Iron alloy electrodeposition on rotating disk electrode N the nickel-iron electrodeposition process, we have developed one-dimensional numerical model. This model ad can predict characteristic features of the nickel-iron sys- tem. this work was supported
The CALICE Collaboration
2015-01-01T23:59:59.000Z
Validation of hadronic models using CALICE highly granular calorimeters, 15th International Conference on Calorimetry in High Energy Physics
Dannheim, D
2015-01-01T23:59:59.000Z
Validation of hadron shower models using data from CALICE, The 2013 European Physical Society Conference on High Energy Physics
Modelling of Melt Damage of Tungsten Armour under Multiple Transients Expected in ITER and Validations Against JET-ILW Experiments
Collins, Kent Michael
1995-01-01T23:59:59.000Z
This thesis documents efforts to validate two elements related to an operating-speed-based geometric design consistency evaluation procedure: (1) the speed reduction estimation ability of the model, and (2) assumptions about acceleration...
Modelling, Identification and Experimental Validation of a Hydraulic Manipulator Joint for Control
Papadopoulos, Evangelos
Modelling, Identification and Experimental Validation of a Hydraulic Manipulator Joint for Control increase efficiency. However, the control of manipulators interacting with an environment is very complex complicate the control of manipulators in contact with their environment. Unlike electrical actuators
Climatically Diverse Data Set for Flat-Plate PV Module Model Validations (Presentation)
Marion, B.
2013-05-01T23:59:59.000Z
Photovoltaic (PV) module I-V curves were measured at Florida, Colorado, and Oregon locations to provide data for the validation and development of models used for predicting the performance of PV modules.
Broader source: Energy.gov [DOE]
Presentation given by General Motors at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about validation of material models...
Numerical modelling of hyperbolic conservation laws using bicharacteristics
Hanke-Bourgeois, Martin
volume methods -1- #12;Overview I. Hyperbolic Conservation Laws Theory of bicharacteristics and evolution, bicharacteritsics stability, accuracy, error analysis III. Numerical Experiments: Wave equation system, Euler eqs finite volume methods -2- #12;· airflow · hydraulic schock · meteorological flow Source: efluid
ASYMPTOTIC AND NUMERICAL MODELLING OF FLOWS IN FRACTURED POROUS MEDIA
Paris-Sud XI, Université de
numerical results are reported showing different kinds of flows in the case of impermeable or partially. Joliot Curie, F-13453 Marseille cedex 13. Email : [angot,fboyer,fhubert]@cmi.univ-mrs.fr cl EDP Sciences
Roberts, Jesse D.; Chang, Grace; Jones, Craig
2014-09-01T23:59:59.000Z
The numerical model, SWAN (Simulating WAves Nearshore) , was used to simulate wave conditions in Kaneohe Bay, HI in order to determine the effects of wave energy converter ( WEC ) devices on the propagation of waves into shore. A nested SWAN model was validated then used to evaluate a range of initial wave conditions: significant wave heights (H s ) , peak periods (T p ) , and mean wave directions ( MWD) . Differences between wave height s in the presence and absence of WEC device s were assessed at locations in shore of the WEC array. The maximum decrease in wave height due to the WEC s was predicted to be approximately 6% at 5 m and 10 m water depths. Th is occurred for model initiation parameters of H s = 3 m (for 5 m water depth) or 4 m (10 m water depth) , T p = 10 s, and MWD = 330deg . Subsequently, bottom orbital velocities were found to decrease by about 6%.
Verification and validation benchmarks.
Oberkampf, William Louis; Trucano, Timothy Guy
2007-02-01T23:59:59.000Z
Verification and validation (V&V) are the primary means to assess the accuracy and reliability of computational simulations. V&V methods and procedures have fundamentally improved the credibility of simulations in several high-consequence fields, such as nuclear reactor safety, underground nuclear waste storage, and nuclear weapon safety. Although the terminology is not uniform across engineering disciplines, code verification deals with assessing the reliability of the software coding, and solution verification deals with assessing the numerical accuracy of the solution to a computational model. Validation addresses the physics modeling accuracy of a computational simulation by comparing the computational results with experimental data. Code verification benchmarks and validation benchmarks have been constructed for a number of years in every field of computational simulation. However, no comprehensive guidelines have been proposed for the construction and use of V&V benchmarks. For example, the field of nuclear reactor safety has not focused on code verification benchmarks, but it has placed great emphasis on developing validation benchmarks. Many of these validation benchmarks are closely related to the operations of actual reactors at near-safety-critical conditions, as opposed to being more fundamental-physics benchmarks. This paper presents recommendations for the effective design and use of code verification benchmarks based on manufactured solutions, classical analytical solutions, and highly accurate numerical solutions. In addition, this paper presents recommendations for the design and use of validation benchmarks, highlighting the careful design of building-block experiments, the estimation of experimental measurement uncertainty for both inputs and outputs to the code, validation metrics, and the role of model calibration in validation. It is argued that the understanding of predictive capability of a computational model is built on the level of achievement in V&V activities, how closely related the V&V benchmarks are to the actual application of interest, and the quantification of uncertainties related to the application of interest.
Precise Steps for Choreography Modeling for SOA Validation and Verification
Southampton, University of
as the next evolutionary step to cope with the software complexity of ERP systems where monolithic approaches component models by verification. This fits well into the model-driven development approach practiced at SAP
System-Level Modeling of Energy in TLM for Early Validation of Power and Thermal Management
Paris-Sud XI, Université de
System-Level Modeling of Energy in TLM for Early Validation of Power and Thermal Management Tayeb--Modern systems-on-a-chip are equipped with power architectures, allowing to control the consumption of individual; hence the need for early system-level models of power consumption. B. High-Level Models and Simulation
Retrievals of Carbon Dioxide from GOSAT: Validation, model comparison and approach development
Retrievals of Carbon Dioxide from GOSAT: Validation, model comparison and approach development properties of aerosol and cirrus particles. 3. Model Comparison Retrievals of XCO2 were performed on cloud and compared to the CarbonTracker model. The retrieval averaging kernels were applied to Carbon
Numerical Modeling of CIGS Solar Cells: Definition of the Baseline and
Sites, James R.
Thesis Numerical Modeling of CIGS Solar Cells: Definition of the Baseline and Explanation our supervision by Markus Gloeckler entitled "Numerical Modeling of CIGS Solar Cells: Definition. A three-layer structure, simulating a Cu(InGa)Se2 (CIGS) heterojunction solar cell, was set up using
NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE
Sites, James R.
NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE M. Gloeckler, A important complications that are often found in experimental CIGS and CdTe solar cells. 1. INTRODUCTION Numerical modeling of polycrystalline thin-film solar cells is an important strategy to test the viability
Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal waters
Lee, Zhongping
Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal waters in the upper ocean, the vertical distribution of solar radiation (ESR) in the shortwave domain plays (2005), Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal
Numerical analysis of a one-dimensional elastodynamic model of dry friction and unilateral contact
Renard, Yves - Pôle de Mathématiques, Institut National des Sciences Appliquées de Lyon
.e. hyperbolic) model with dry friction. Since we consider a Coulomb friction law with a slip velocity dependentNumerical analysis of a one-dimensional elastodynamic model of dry friction and unilateral contact in the numerical analysis of more elaborated dynamic purely elastic problems with dry friction. Ó 2001 Elsevier
ON ACCURACY OF NUMERICAL EMC/EMI MODELING OVER A WIDE FREQUENCY RANGE
Loyka, Sergey
1 ON ACCURACY OF NUMERICAL EMC/EMI MODELING OVER A WIDE FREQUENCY RANGE Sergey Loyka EMC Lab: loyka@nemc.belpak.minsk.by Abstract - Numerical EMC/EMI modeling over a wide frequency range requires computational efficiency is proposed. I. INTRODUCTION Almost all the EMC problems are wide frequency range ones
Numerical modeling of short pulse laser interaction with Au nanoparticle surrounded by water
Zhigilei, Leonid V.
Numerical modeling of short pulse laser interaction with Au nanoparticle surrounded by water Alexey, University of Virginia, USA Available online 3 February 2007 Abstract Short pulse laser interaction modeling; Nanoparticles; Cell targeting; Laser damage 1. Introduction Short pulse laser irradiation
Thermoelectric Generators for Automotive Waste Heat Recovery Systems Part I: Numerical Modeling
Xu, Xianfan
Thermoelectric Generators for Automotive Waste Heat Recovery Systems Part I: Numerical Modeling (TEG) designed for automotive waste heat recovery systems. This model is capable of computing bismuth telluride are considered for thermoelectric modules (TEMs) for conversion of waste heat from
Electrical Model Development and Validation for Distributed Resources
Simoes, M. G.; Palle, B.; Chakraborty, S.; Uriarte, C.
2007-04-01T23:59:59.000Z
This project focuses on the development of electrical models for small (1-MW) distributed resources at the National Renewable Energy Laboratory's Distributed Energy Resources Test Facility.
arrays model validation: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of Panama Canal System Operations Engineering Websites Summary: and modeled in LTSA. Safety and progress requirements are formally expressed as processes that can. It is...
activity model validation: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of Panama Canal System Operations Engineering Websites Summary: and modeled in LTSA. Safety and progress requirements are formally expressed as processes that can. It is...
Numerical Model of a Tensioner System and Flex Joint
Huang, Han
2013-07-27T23:59:59.000Z
Top Tensioned Riser (TTR) and Steel Catenary Riser (SCR) are often used in a floating oil/gas production system deployed in deep water for oil transport. This study focuses on the improvements to the existing numerical code, known as CABLE3D...
Numerical Modeling of Human Effect on Indoor Propagation
Paris-Sud XI, Université de
several types of obstacles such a brick enclosure walls, one metal heater, two metal wardrobes, two metal antenna placed 85 cm above the floor level. The spatial step is /10, or is the wavelength, chosen by the numerical dispersions. The choice of the spatial step is a compromise between the minimization of inaccuracy
Spatial Statistical Procedures to Validate Input Data in Energy Models
Johannesson, G.; Stewart, J.; Barr, C.; Brady Sabeff, L.; George, R.; Heimiller, D.; Milbrandt, A.
2006-01-01T23:59:59.000Z
Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, economic trends, and other primarily non-energy related uses. Systematic collection of empirical data solely for regional, national, and global energy modeling has not been established as in the abovementioned fields. Empirical and modeled data relevant to energy modeling is reported and available at various spatial and temporal scales that might or might not be those needed and used by the energy modeling community. The incorrect representation of spatial and temporal components of these data sets can result in energy models producing misleading conclusions, especially in cases of newly evolving technologies with spatial and temporal operating characteristics different from the dominant fossil and nuclear technologies that powered the energy economy over the last two hundred years. Increased private and government research and development and public interest in alternative technologies that have a benign effect on the climate and the environment have spurred interest in wind, solar, hydrogen, and other alternative energy sources and energy carriers. Many of these technologies require much finer spatial and temporal detail to determine optimal engineering designs, resource availability, and market potential. This paper presents exploratory and modeling techniques in spatial statistics that can improve the usefulness of empirical and modeled data sets that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) predicting missing data, and (3) merging spatial data sets. In addition, we introduce relevant statistical software models commonly used in the field for various sizes and types of data sets.
Numerical modelling of a radio-frequency micro ion thruster
Tsay, Michael Meng-Tsuan
2006-01-01T23:59:59.000Z
A simple performance model is developed for an inductively-coupled radio-frequency micro ion thruster. Methods of particle and energy balance are utilized for modeling the chamber plasma discharge. A transformer model is ...
70 MPa Fast-Fill Modeling & Validation Experiments
. 8365 DOE Tank Safety Workshop April 29, 2010 SAND Number: 2010-2830 P Sandia National Laboratories connections (network) One dimensional flow in tubing Vessels modeled as single control volumes
O`ahu Grid Study: Validation of Grid Models
16, 2007 5 2-2 Comparison of the annual energy production (MWh), by unit type, between the historical 2007 HECO energy production and the GE MAPSTM model simulation 6 2-3 Comparison of the fuel consumption
THE FERNALD DOSIMETRY RECONSTRUCTION PROJECT Environmental Pathways -Models and Validation
and Deposition Models . 19 Building Wake Effects and Plume Rise . 23 Resuspension of Particulates . . . . . 24 the FMPC N. Soil Data for Locations near the FMPC o. Resuspension of Particulates p. Radon, Radon
Fractional Calculus in Hydrologic Modeling: A Numerical Perspective
David A. Benson; Mark M. Meerschaert; Jordan Revielle
2012-01-01T23:59:59.000Z
Fractional derivatives can be viewed either as a handy extension of classical calculus or, more deeply, as mathematical operators defined by natural phenomena. This follows the view that the diffusion equation is defined as the governing equation of a Brownian motion. In this paper, we emphasize that fractional derivatives come from the governing equations of stable Levy motion, and that fractional integration is the corresponding inverse operator. Fractional integration, and its multi-dimensional extensions derived in this way, are intimately tied to fractional Brownian (and Levy) motions and noises. By following these general principles, we discuss the Eulerian and Lagrangian numerical solutions to fractional partial differential equations, and Eulerian methods for stochastic integrals. These numerical approximations illuminate the essential nature of the fractional calculus.
Hessel, R; Foster, D; Aceves, S; Flowers, D; Pitz, B; Dec, J; Sjoberg, M; Babajimopoulos, A
2007-04-23T23:59:59.000Z
Multi-zone CFD simulations with detailed kinetics were used to model engine experiments performed on a diesel engine that was converted for single cylinder, HCCI operation, here using iso-octane as the fuel. The modeling goals were to validate the method (multi-zone combustion modeling) and the reaction mechanism (LLNL 857 species iso-octane), both of which performed very well. The purpose of this paper is to document the validation findings and to set the ground work for further analysis of the results by first looking at CO emissions characteristics with varying equivalence ratio.
Preliminary Validation Using in vivo Measures of a Macroscopic Electrical Model of the Heart
Coudière, Yves
Preliminary Validation Using in vivo Measures of a Macroscopic Electrical Model of the Heart Maxime Antipolis, France 2 National Institutes of Health, National Heart Lung and Blood Institute, Laboratory of the cardiac electrical activity in a canine heart coupled with simulations done using macroscopic models
Empirical Validation of the Thermal Model of a Passive Solar Cell test
Paris-Sud XI, Université de
1 Empirical Validation of the Thermal Model of a Passive Solar Cell test Thierry Alex MARA, two samples of experimental data are required. The first one is used to calibrate our model the second; Calibration; Sensitivity analysis; Spectral analysis; Time- frequency analysis. 1.Introduction
Numerical modeling of geothermal systems with applications to Krafla, Iceland and Olkaria, Kenya
Bodvarsson, G.S.
1987-08-01T23:59:59.000Z
The use of numerical models for the evaluation of the generating potential of high temperature geothermal fields has increased rapidly in recent years. In the present paper a unified numerical approach to the modeling of geothermal systems is discussed and the results of recent modeling of the Krafla geothermal field in Iceland and the Olkaria, Kenya, are described. Emphasis is placed on describing the methodology using examples from the two geothermal fields.
Modeling HIV Immune Response and Validation with Clinical Data
and parameters describing vi- ral production and clearance, cell infection and death rate, treatment efficacy, and stimulation by antigens other than HIV. A stability analysis illustrates the capability of this model in admitting multiple locally asymptotically stable (locally a.s.) off-treatment equilibria. The phenomenon
Numerical simulation of a lattice polymer model at its integrable point
A. Bedini; A. L. Owczarek; T. Prellberg
2013-05-21T23:59:59.000Z
We revisit an integrable lattice model of polymer collapse using numerical simulations. This model was first studied by Bl\\"ote and Nienhuis in J. Phys. A. {\\bf 22}, 1415 (1989) and it describes polymers with some attraction, providing thus a model for the polymer collapse transition. At a particular set of Boltzmann weights the model is integrable and the exponents $\
Bürger, Raimund
-dimensional model of sedimentation of suspensions of small solid particles dispersed in a viscous fluid. This model accepted spatially one-dimensional sedimentation model [35] gives rise to one scalar, nonlinear hyperbolicINTERNATIONAL JOURNAL OF c 2011 Institute for Scientific NUMERICAL ANALYSIS AND MODELING Computing
Bürger, Raimund
-dimensional model of sedimentation of suspensions of small solid particles dispersed in a viscous fluid. This model accepted spatially one-dimensional sedimentation model [35] gives rise to one scalar, nonlinear hyperbolicINTERNATIONAL JOURNAL OF c 2012 Institute for Scientific NUMERICAL ANALYSIS AND MODELING Computing
Numerical modeling of wave propagation in random anisotropic heterogeneous elastic media
Boyer, Edmond
Numerical modeling of wave propagation in random anisotropic heterogeneous elastic media Q.-A. Ta numerical experiments that were performed on wave propagation in a randomly generated anisotropic used for the propagation of waves in geophysical media are not compatible with the surface recordings
Chen, Qingyan "Yan"
. "Improvements on FFD modeling by using different numerical schemes," Numerical Heat Transfer, Part B (m) t time step (s) Greek Symbols ratio of mass flow rate to a flow domain over that out of the flow: Fundamentals, 58(1), 1-16. #12;2 Abstract Indoor environm ent design and air m anagement in buildings requires
Numerical models of caldera deformation: Effects of multiphase and multicomponent hydrothermal studies addressing the effects of multiphase flow on crustal mechanics have been attempted. Recent numerical simulations of multiphase (liquid-gas), multicomponent (H2OÂCO2) hydrothermal fluid flow
USING LEARNING MACHINES TO CREATE SOLAR RADIATION MAPS FROM NUMERICAL WEATHER PREDICTION MODELS,
Paris-Sud XI, UniversitÃ© de
USING LEARNING MACHINES TO CREATE SOLAR RADIATION MAPS FROM NUMERICAL WEATHER PREDICTION MODELS to develop a methodology to generate solar radiation maps using information from different sources. First with conclusions and next works in the last section. Keywords: Solar Radiation maps, Numerical Weather Predictions
LDV HVAC Model Development and Validation | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM to 2:05PMDOE-STD-1107-97LSEED:LDV HVAC Model
Development and Validation of an Advanced Stimulation Prediction Model for
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model,DOE Facility DatabaseMichigan: EnergyKansas:DetroitOpen Energy1987)
A/C Model Development and Validation | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1 A Strategic Framework for SMRA View from the BridgeA/C Model
2013 CEF RUN - PHASE 1 DATA ANALYSIS AND MODEL VALIDATION
Choi, A.
2014-05-08T23:59:59.000Z
Phase 1 of the 2013 Cold cap Evaluation Furnace (CEF) test was completed on June 3, 2013 after a 5-day round-the-clock feeding and pouring operation. The main goal of the test was to characterize the CEF off-gas produced from a nitric-formic acid flowsheet feed and confirm whether the CEF platform is capable of producing scalable off-gas data necessary for the revision of the DWPF melter off-gas flammability model; the revised model will be used to define new safety controls on the key operating parameters for the nitric-glycolic acid flowsheet feeds including total organic carbon (TOC). Whether the CEF off-gas data were scalable for the purpose of predicting the potential flammability of the DWPF melter exhaust was determined by comparing the predicted H{sub 2} and CO concentrations using the current DWPF melter off-gas flammability model to those measured during Phase 1; data were deemed scalable if the calculated fractional conversions of TOC-to-H{sub 2} and TOC-to-CO at varying melter vapor space temperatures were found to trend and further bound the respective measured data with some margin of safety. Being scalable thus means that for a given feed chemistry the instantaneous flow rates of H{sub 2} and CO in the DWPF melter exhaust can be estimated with some degree of conservatism by multiplying those of the respective gases from a pilot-scale melter by the feed rate ratio. This report documents the results of the Phase 1 data analysis and the necessary calculations performed to determine the scalability of the CEF off-gas data. A total of six steady state runs were made during Phase 1 under non-bubbled conditions by varying the CEF vapor space temperature from near 700 to below 300°C, as measured in a thermowell (T{sub tw}). At each steady state temperature, the off-gas composition was monitored continuously for two hours using MS, GC, and FTIR in order to track mainly H{sub 2}, CO, CO{sub 2}, NO{sub x}, and organic gases such as CH{sub 4}. The standard deviation of the average vapor space temperature during each steady state ranged from 2 to 6°C; however, those of the measured off-gas data were much larger due to the inherent cold cap instabilities in the slurry-fed melters. In order to predict the off-gas composition at the sampling location downstream of the film cooler, the measured feed composition was charge-reconciled and input into the DWPF melter off-gas flammability model, which was then run under the conditions for each of the six Phase 1 steady states. In doing so, it was necessary to perform an overall heat/mass balance calculation from the melter to the Off-Gas Condensate Tank (OGCT) in order to estimate the rate of air inleakage as well as the true gas temperature in the CEF vapor space (T{sub gas}) during each steady state by taking into account the effects of thermal radiation on the measured temperature (T{sub tw}). The results of Phase 1 data analysis and subsequent model runs showed that the predicted concentrations of H{sub 2} and CO by the DWPF model correctly trended and further bounded the respective measured data in the CEF off-gas by over predicting the TOC-to-H{sub 2} and TOC-to-CO conversion ratios by a factor of 2 to 5; an exception was the 7X over prediction of the latter at T{sub gas} = 371°C but the impact of CO on the off-gas flammability potential is only minor compared to that of H{sub 2}. More importantly, the seemingly-excessive over prediction of the TOC-to-H{sub 2} conversion by a factor of 4 or higher at T{sub gas} < ~350°C was attributed to the conservative antifoam decomposition scheme added recently to the model and therefore is considered a modeling issue and not a design issue. At T{sub gas} > ~350°C, the predicted TOC-to-H{sub 2} conversions were closer to but still higher than the measured data by a factor of 2, which may be regarded as adequate from the safety margin standpoint. The heat/mass balance calculations also showed that the correlation between T{sub tw} and T{sub gas} in the CEF vapor space was close to that of the ½ scale SGM, whose data were ta
Development and validation of a combustion model for a fuel cell off-gas burner
Collins, William Tristan
2008-10-14T23:59:59.000Z
Development and Validation of a Combustion Model for a Fuel Cell Off-Gas Burner W. Tristan Collins Magdalene College University of Cambridge A dissertation submitted to the University of Cambridge for the degree of Doctor of Philosophy June 2008... Development and Validation of a Combustion Model for a Fuel Cell Off-Gas Burner W. Tristan Collins A low-emissions power generator comprising a solid oxide fuel cell coupled to a gas turbine has been developed by Rolls-Royce Fuel Cell Systems. As part...
Empirical validation of the thermal model of a passive solar cell test
Mara, T A; Boyer, H; Mamode, M
2012-01-01T23:59:59.000Z
The paper deals with an empirical validation of a building thermal model. We put the emphasis on sensitivity analysis and on research of inputs/residual correlation to improve our model. In this article, we apply a sensitivity analysis technique in the frequency domain to point out the more important parameters of the model. Then, we compare measured and predicted data of indoor dry-air temperature. When the model is not accurate enough, recourse to time-frequency analysis is of great help to identify the inputs responsible for the major part of error. In our approach, two samples of experimental data are required. The first one is used to calibrate our model the second one to really validate the optimized model
Boyer, Edmond
waves are expected to be generated mostly along shorelines by nonlinear interactions of the shorter wind-generated the wind-generated wind sea and swells, with periods shorter than 30 s, into sub-harmonics. For waves
Analytical-Numerical Modeling Of Komatiite Lava Emplacement And...
Modeling Of Komatiite Lava Emplacement And Thermal Erosion At Perseverance, Western Australia Jump to: navigation, search OpenEI Reference LibraryAdd to library...
Numerical modeling of elastic wave scattering by near-surface heterogeneities
Al Muhaidib, Abdulaziz
2013-01-01T23:59:59.000Z
A perturbation method for elastic waves and numerical forward modeling are used to calculate the effects of seismic wave scattering from arbitrary shape shallow subsurface heterogeneities. Wave propagation is simulated ...
2D-Modelling of pellet injection in the poloidal plane: results of numerical tests
Paris-Sud XI, UniversitÃ© de
2D-Modelling of pellet injection in the poloidal plane: results of numerical tests P. Lalousis developed for computing the expansion of pellet-produced clouds in the poloidal plane. The expansion
Seismic scattering attributes to estimate reservoir fracture density : a numerical modeling study
Pearce, Frederick D. (Frederick Douglas), 1978-
2003-01-01T23:59:59.000Z
We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir containing evenly-spaced, discrete, vertical fracture zones. The fracture zones are represented using a ...
Seismic Scattering Attributes to Estimate Reservoir Fracture Density: A Numerical Modeling Study
Pearce, Frederick Douglas
We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir containing evenly-spaced, discrete, vertical fracture zones. The fracture zones are represented using a ...
Ravago Bastardo, Delmira Cristina
2005-08-29T23:59:59.000Z
The main objective of this research is to compare the performance of cyclic steam injection using horizontal wells based on the analytical model developed by Gunadi against that based on numerical simulation. For comparison, ...
Numerically Estimating Internal Models of Dynamic Virtual Objects
Sekuler, Robert
human subjects to manipulate a computer-animated virtual object. This virtual object (vO) was a high, human cognition, human information processing, ideal performer, internal model, virtual object, virtual, specifically how humans acquire an internal model of a dynamic virtual object. Our methodology minimizes
Yaghoobian, Neda; Kleissl, Jan
2012-01-01T23:59:59.000Z
Energy Use – Model Description and Validation Neda Yaghoobian Mechanical and Aerospace Engineering
Validation of a Hot Water Distribution Model Using Laboratory and Field Data
Backman, C.; Hoeschele, M.
2013-07-01T23:59:59.000Z
Characterizing the performance of hot water distribution systems is a critical step in developing best practice guidelines for the design and installation of high performance hot water systems. Developing and validating simulation models is critical to this effort, as well as collecting accurate input data to drive the models. In this project, the ARBI team validated the newly developed TRNSYS Type 604 pipe model against both detailed laboratory and field distribution system performance data. Validation efforts indicate that the model performs very well in handling different pipe materials, insulation cases, and varying hot water load conditions. Limitations of the model include the complexity of setting up the input file and long simulation run times. In addition to completing validation activities, this project looked at recent field hot water studies to better understand use patterns and potential behavioral changes as homeowners convert from conventional storage water heaters to gas tankless units. Based on these datasets, we conclude that the current Energy Factor test procedure overestimates typical use and underestimates the number of hot water draws. This has implications for both equipment and distribution system performance. Gas tankless water heaters were found to impact how people use hot water, but the data does not necessarily suggest an increase in usage. Further study in hot water usage and patterns is needed to better define these characteristics in different climates and home vintages.
Key challenges to model-based design : distinguishing model confidence from model validation
Flanagan, Genevieve (Genevieve Elise Cregar)
2012-01-01T23:59:59.000Z
Model-based design is becoming more prevalent in industry due to increasing complexities in technology while schedules shorten and budgets tighten. Model-based design is a means to substantiate good design under these ...
Giovanni Noselli; Antonio DeSimone
2014-08-26T23:59:59.000Z
We present experimental and numerical results for a model crawler which is able to extract net positional changes from reciprocal shape changes, i.e. 'breathing-like' deformations, thanks to directional, frictional interactions with a textured solid substrate, mediated by flexible inclined feet. We also present a simple reduced model that captures the essential features of the kinematics and energetics of the gait, and compare its predictions with the results from experiments and from numerical simulations.
Development and validation of a two-phase, three-dimensional model for PEM fuel cells.
Chen, Ken Shuang
2010-04-01T23:59:59.000Z
The objectives of this presentation are: (1) To develop and validate a two-phase, three-dimensional transport modelfor simulating PEM fuel cell performance under a wide range of operating conditions; (2) To apply the validated PEM fuel cell model to improve fundamental understanding of key phenomena involved and to identify rate-limiting steps and develop recommendations for improvements so as to accelerate the commercialization of fuel cell technology; (3) The validated PEMFC model can be employed to improve and optimize PEM fuel cell operation. Consequently, the project helps: (i) address the technical barriers on performance, cost, and durability; and (ii) achieve DOE's near-term technical targets on performance, cost, and durability in automotive and stationary applications.
NUMERICAL MODELING OF TURBULENT FLOW IN A COMBUSTION TUNNEL
Ghoniem, A.F.
2013-01-01T23:59:59.000Z
1VJcDona·ld, H. (1979) Combustion r 1 iodeJ·ing in Two and1979) Practical Turbulent-Combustion Interaction Models forInternation on Combustors. Combustion The 17th Symposium
Numerical Modeling of Hydraulic Fracturing in Oil Sands
2008-11-16T23:59:59.000Z
A thermal hydro-mechanical fracture nite element model is developed, which is able to ..... c) Fluid velocity: Darcy's law, in general index form, is given by: vi = Kij.
Numerical Modeling of Seafloor Interation with Steel Catenary Riser
You, Jung Hwan
2012-10-19T23:59:59.000Z
degradation it is possible to simulate the trench formation process and estimate deflections and moments along the riser length. The seabed model is used to perform parametric studies to assess the effects of stiffness, soil strength, amplitude of pipe...
Ductile fracture modeling : theory, experimental investigation and numerical verification
Xue, Liang, 1973-
2007-01-01T23:59:59.000Z
The fracture initiation in ductile materials is governed by the damaging process along the plastic loading path. A new damage plasticity model for ductile fracture is proposed. Experimental results show that fracture ...
Numerically Efficient Water Quality Modeling and Security Applications
Mann, Angelica
2013-02-04T23:59:59.000Z
utilities protect the public against potential contamination events. The first component is a novel water quality modeling framework referred to as Merlion. The linear system describing contaminant spread through the network at the core of Merlion provides...
Efficient Dynamic Modeling, Numerical Optimal Control and Experimental Results for Various Gaits
Stryk, Oskar von
Efficient Dynamic Modeling, Numerical Optimal Control and Experimental Results for Various Gaits. A fully three- dimensional dynamical model of Sony's four-legged robot is used to state an optimal control model and the algorithm for evaluating the dynamics. The formulation of the optimal control problem
Author's personal copy A new 3D numerical model of cosmogenic nuclide 10
Usoskin, Ilya G.
Author's personal copy A new 3D numerical model of cosmogenic nuclide 10 Be production's atmosphere cosmogenic isotopes A new quantitative model of production of the cosmogenic isotope 10 solar energetic particle events. The model was tested against the results of direct measurements
Numerical Experiments of Some Krylov Subspace Methods for Black Oil Model
Lai, Choi-Hong
Numerical Experiments of Some Krylov Subspace Methods for Black Oil Model Jianwen Cao #3; Choi of linear systems originated from the black oil model in oil reservoir simulation. There exists some Krylov subspace algorithms and pre- conditioning techniques for the black oil model as appeared in the literature
Adegbesan, K.O.; Donnelly, J.K.; Moore, R.G.; Bennion, D.W.
1986-08-01T23:59:59.000Z
Multiresponse kinetic models are established for the low-temperature oxidation (LTO) reaction of Athabasca oil sands bitumen. The models provide adequate description of the overall rate of oxygen consumption and of the reactions of the liquid phase bitumen components. The LTO models are suitable for use in the in situ combustion numerical simulators of oil sands.
A CONSISTENT MODELLING METHODOLOGY FOR SECONDARY1 SETTLING TANKS: A RELIABLE NUMERICAL METHOD2
Bürger, Raimund
relations for hindered settling, compression and dispersion can be used within the model, allowing the user, continuous sedimentation, secondary clarifier, simulation5 model, partial differential equation6 NomenclatureA CONSISTENT MODELLING METHODOLOGY FOR SECONDARY1 SETTLING TANKS: A RELIABLE NUMERICAL METHOD2
VALIDATION OF PV PERFORMANCE MODELS USING SATELLITE-BASED IRRADIANCE MEASUREMENTS: A CASE STUDY
Perez, Richard R.
VALIDATION OF PV PERFORMANCE MODELS USING SATELLITE-BASED IRRADIANCE MEASUREMENTS: A CASE STUDY Clean Power Research Kirkland, WA e-mail: aparkins@cleanpower.com ABSTRACT Photovoltaic (PV) system and existing PV systems under a wide variety of environmental conditions. Ground based meteorological
CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL
Heinemann, Detlev
CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL Enio B-970, SP, Brazil. Phone + 55 12 39456741, Fax + 55 12 39456810, fernando@dge.inpe.br. Samuel L. Abreu, Hans, Federal University of Santa Catarina -UFSC, Florianópolis, 88040-900, (SC), Brazil. Richard Perez
Broader source: Energy.gov [DOE]
Project objectives: Develop a true 3D hydro-thermal fracturing and proppant flow/transport simulator that is particularly suited for EGS reservoir creation. Perform laboratory scale model tests of hydraulic fracturing and proppant flow/transport using a polyaxial loading device, and use the laboratory results to test and validate the 3D simulator.
MODELING AND VALIDATION OF A HIGH SPEED ROTARY PWM ON/OFF VALVE Haink C. Tu
Li, Perry Y.
MODELING AND VALIDATION OF A HIGH SPEED ROTARY PWM ON/OFF VALVE Haink C. Tu Center for Compact-speed on/off valves are a critical technology for enabling digital control of hydraulic systems via pulse-width- modulation (PWM). High-speed valves, when used in virtually variable displacement pumps (VVDP), increase
Model Validation at the 204 MW New Mexico Wind Energy Center: Preprint
Muljadi, E.; Butterfield, C. P.; Ellis, A.; Mechenbier, J.; Hochheimer, J.; Young, R.; Miller, N.; Delmerico, R.; Zavadil, R.; Smith, J. C.
2006-06-01T23:59:59.000Z
In this paper, we describe methods to derive and validate equivalent models for a large wind farm. FPL Energy's 204-MW New Mexico Wind Energy Center, which is interconnected to the Public Service Company of New Mexico (PNM) transmission system, was used as a case study. The methods described are applicable to any large wind power plant.
VERIFICATION AND VALIDATION OF MODELS IN THE NATIONAL SCIENCE DIGITAL LIBRARY
Stevenson, D. E. "Steve"
VERIFICATION AND VALIDATION OF MODELS IN THE NATIONAL SCIENCE DIGITAL LIBRARY D. E. STEVENSON Abstract. The National Science Digital Library is the Nation's online library for education and re- search Science Digital Library in a Nutshell "The National Science Foundation's (NSF) National Science
IMPROVED NUMERICAL METHODS FOR MODELING RIVER-AQUIFER INTERACTION.
Tidwell, Vincent C.; Sue Tillery; Phillip King
2008-09-01T23:59:59.000Z
A new option for Local Time-Stepping (LTS) was developed to use in conjunction with the multiple-refined-area grid capability of the U.S. Geological Survey's (USGS) groundwater modeling program, MODFLOW-LGR (MF-LGR). The LTS option allows each local, refined-area grid to simulate multiple stress periods within each stress period of a coarser, regional grid. This option is an alternative to the current method of MF-LGR whereby the refined grids are required to have the same stress period and time-step structure as the coarse grid. The MF-LGR method for simulating multiple-refined grids essentially defines each grid as a complete model, then for each coarse grid time-step, iteratively runs each model until the head and flux changes at the interfacing boundaries of the models are less than some specified tolerances. Use of the LTS option is illustrated in two hypothetical test cases consisting of a dual well pumping system and a hydraulically connected stream-aquifer system, and one field application. Each of the hypothetical test cases was simulated with multiple scenarios including an LTS scenario, which combined a monthly stress period for a coarse grid model with a daily stress period for a refined grid model. The other scenarios simulated various combinations of grid spacing and temporal refinement using standard MODFLOW model constructs. The field application simulated an irrigated corridor along the Lower Rio Grande River in New Mexico, with refinement of a small agricultural area in the irrigated corridor.The results from the LTS scenarios for the hypothetical test cases closely replicated the results from the true scenarios in the refined areas of interest. The head errors of the LTS scenarios were much smaller than from the other scenarios in relation to the true solution, and the run times for the LTS models were three to six times faster than the true models for the dual well and stream-aquifer test cases, respectively. The results of the field application show that better estimates of daily stream leakage can be made with the LTS simulation, thereby improving the efficiency of daily operations for an agricultural irrigation system. ACKNOWLEDGEMENTSThe authors appreciatively acknowledge support for Sue Tillery provided by Sandia National Laboratories' through a Campus Executive Laboratory Directed Research and Development (LDRD) research project.Funding for this study was provided by Directed Research and Development (LDRD) research project.
Numerical Integration Numerical Summation
Cohen, Henri
Numerical Integration Numerical Summation Numerical Extrapolation Numerical Recipes for Multiprecision Computations #12;Numerical Integration Numerical Summation Numerical Extrapolation Multiprecision, integration, summation, extrapolation, evaluation of continued fractions, Euler products and sums, complete
Lattice Percolation Approach to Numerical Modeling of Tissue Aging
Privman, Vladimir; Libert, Sergiy
2015-01-01T23:59:59.000Z
We describe a percolation-type approach to modeling of the processes of aging and certain other properties of tissues analyzed as systems consisting of interacting cells. Tissues are considered as structures made of regular healthy, senescent, dead (apoptotic) cells, and studied dynamically, with the ongoing processes including regular cell division to fill vacant sites left by dead cells, healthy cells becoming senescent or dying, and other processes. Statistical-mechanics description can provide patterns of time dependence and snapshots of morphological system properties. An illustrative application of the developed theoretical modeling approach is reported, confirming recent experimental findings that inhibition of senescence can lead to extended lifespan.
Climate Change Impacts for Conterminous USA: An Integrated Assessment Part 2. Models and Validation
Thomson, Allison M.; Rosenberg, Norman J.; Izaurralde, R Cesar C.; Brown, Robert A.
2005-03-01T23:59:59.000Z
As CO{sub 2} and other greenhouse gases accumulate in the atmosphere and contribute to rising global temperatures, it is important to examine how a changing climate may affect natural and managed ecosystems. In this series of papers, we study the impacts of climate change on agriculture, water resources and natural ecosystems in the conterminous United States using a suite of climate change predictions from General Circulation Models (GCMs) as described in Part 1. Here we describe the agriculture model EPIC and the HUMUS water model and validate them with historical crop yields and streamflow data. We compare EPIC simulated grain and forage crop yields with historical crop yields from the US Department of Agriculture and find an acceptable level of agreement for this study. The validation of HUMUS simulated streamflow with estimates of natural streamflow from the US Geological Survey shows that the model is able to reproduce significant relationships and capture major trends.
Oudini, N. [Laboratoire des plasmas de décharges, Centre de Développement des Technologies Avancées, Cité du 20 Aout BP 17 Baba Hassen, 16081 Algiers (Algeria); Taccogna, F. [Istituto di Metodologie Inorganiche e dei Plasmi, CNR, via Amendola 122/D, 70126 Bari (Italy); Bendib, A. [Laboratoire d'Electronique Quantique, Faculté de Physique, USTHB, El Alia BP 32, Bab Ezzouar 16111, Algiers (Algeria); Aanesland, A. [Laboratoire de Physique des Plasmas (CNRS, Ecole Polytechnique, Sorbonne Universités, UPMC Univ Paris 06, Univ Paris-Sud), École Polytechnique, 91128 Palaiseau Cedex (France)
2014-06-15T23:59:59.000Z
Laser photo-detachment is used as a method to measure or determine the negative ion density and temperature in electronegative plasmas. In essence, the method consists of producing an electropositive channel (negative ion free region) via pulsed laser photo-detachment within an electronegative plasma bulk. Electrostatic probes placed in this channel measure the change in the electron density. A second pulse might be used to track the negative ion recovery. From this, the negative ion density and temperature can be determined. We study the formation and relaxation of the electropositive channel via a two-dimensional Particle-In-Cell/Mote Carlo collision model. The simulation is mainly carried out in a Hydrogen plasma with an electronegativity of ??=?1, with a parametric study for ? up to 20. The temporal and spatial evolution of the plasma potential and the electron densities shows the formation of a double layer (DL) confining the photo-detached electrons within the electropositive channel. This DL evolves into two fronts that move in the opposite directions inside and outside of the laser spot region. As a consequence, within the laser spot region, the background and photo-detached electron energy distribution function relaxes/thermalizes via collisionless effects such as Fermi acceleration and Landau damping. Moreover, the simulations show that collisional effects and the DL electric field strength might play a non-negligible role in the negative ion recovery within the laser spot region, leading to a two-temperature negative ion distribution. The latter result might have important effects in the determination of the negative ion density and temperature from laser photo detachment diagnostic.
Numerical modeling of an all vanadium redox flow battery.
Clausen, Jonathan R.; Brunini, Victor E.; Moffat, Harry K.; Martinez, Mario J.
2014-01-01T23:59:59.000Z
We develop a capability to simulate reduction-oxidation (redox) flow batteries in the Sierra Multi-Mechanics code base. Specifically, we focus on all-vanadium redox flow batteries; however, the capability is general in implementation and could be adopted to other chemistries. The electrochemical and porous flow models follow those developed in the recent publication by [28]. We review the model implemented in this work and its assumptions, and we show several verification cases including a binary electrolyte, and a battery half-cell. Then, we compare our model implementation with the experimental results shown in [28], with good agreement seen. Next, a sensitivity study is conducted for the major model parameters, which is beneficial in targeting specific features of the redox flow cell for improvement. Lastly, we simulate a three-dimensional version of the flow cell to determine the impact of plenum channels on the performance of the cell. Such channels are frequently seen in experimental designs where the current collector plates are borrowed from fuel cell designs. These designs use a serpentine channel etched into a solid collector plate.
EFFICIENT NUMERICAL SOLUTION TECHNIQUES IN COMPOSITION MODEL 1
on the reservoir pressure and saturation pressure. A blackÂoil model works well in simulating the waterflooding The objective of reservoir simulation is to understand the complex chemical, physical, and fluid flow processes occurring in a petroleum reservoir sufficiently well to be able to optimize the recovery of hydrocarbon
Huang, Zhenyu; Du, Pengwei; Kosterev, Dmitry; Yang, Steve
2013-05-01T23:59:59.000Z
Disturbance data recorded by phasor measurement units (PMU) offers opportunities to improve the integrity of dynamic models. However, manually tuning parameters through play-back events demands significant efforts and engineering experiences. In this paper, a calibration method using the extended Kalman filter (EKF) technique is proposed. The formulation of EKF with parameter calibration is discussed. Case studies are presented to demonstrate its validity. The proposed calibration method is cost-effective, complementary to traditional equipment testing for improving dynamic model quality.
Joint physical and numerical modeling of water distribution networks.
Zimmerman, Adam; O'Hern, Timothy John; Orear, Leslie Jr.; Kajder, Karen C.; Webb, Stephen Walter; Cappelle, Malynda A.; Khalsa, Siri Sahib; Wright, Jerome L.; Sun, Amy Cha-Tien; Chwirka, J. Benjamin; Hartenberger, Joel David; McKenna, Sean Andrew; van Bloemen Waanders, Bart Gustaaf; McGrath, Lucas K.; Ho, Clifford Kuofei
2009-01-01T23:59:59.000Z
This report summarizes the experimental and modeling effort undertaken to understand solute mixing in a water distribution network conducted during the last year of a 3-year project. The experimental effort involves measurement of extent of mixing within different configurations of pipe networks, measurement of dynamic mixing in a single mixing tank, and measurement of dynamic solute mixing in a combined network-tank configuration. High resolution analysis of turbulence mixing is carried out via high speed photography as well as 3D finite-volume based Large Eddy Simulation turbulence models. Macroscopic mixing rules based on flow momentum balance are also explored, and in some cases, implemented in EPANET. A new version EPANET code was developed to yield better mixing predictions. The impact of a storage tank on pipe mixing in a combined pipe-tank network during diurnal fill-and-drain cycles is assessed. Preliminary comparison between dynamic pilot data and EPANET-BAM is also reported.
Development and validation of detailed controls models of the Nelson River Bipole 1 HVDC system
Kuffel, P.; Kent, K.L.; Mazur, G.B.; Weekes, M.A. (Manitoba Hydro, Winnipeg (Canada))
1993-01-01T23:59:59.000Z
With the Nelson River Bipole 1 mercury arc valve group replacement project and planning for the expansion of the Nelson River HVDC system with a third bipole underway, it was decided to pursue a program to develop and validate detailed models of the existing HVDC transmission facilities and their associated ac systems for use in system studies. The first phase of the program concentrated on the development of detailed controls models associated with the Bipole 1 transmission facility. Based on previous experience at Manitoba Hydro with the Electromagnetic Transient DC simulation program (EMTDC), it was decided that model development and validation would use this program. This paper presents the reasons behind the development of detailed models, the methods used in developing models related to Bipole 1, results of validation tests, difficulties encountered during the process, and the overall benefits resulting from the project. An example of applying the models to investigate a low frequency oscillation which has occurred on the dc system in the past is also presented.
On the validity of drift-reduced fluid models for tokamak plasma simulation
Leddy, Jarrod; Romanelli, Michele
2015-01-01T23:59:59.000Z
Drift-reduced plasma fluid models are commonly used in plasma physics for analytics and simulations; however, the validity of such models must be veri?ed for the regions of parameter space in which tokamak plasmas exist. By looking at the linear behaviour of drift-reduced and full-velocity models one can determine that the physics lost through the simplification that the drift-reduction provides is important in the core region of the tokamak. It is more acceptable for the edge-region but one must determine speci?cally for a given simulation if such a model is appropriate.
Avedisian, C. T. (Cornell University, Ithaca, NY); Presser, Cary (National Institute of Standard & Technology, Gaithersburg, MD); DesJardin, Paul Edward (University at Buffalo, New York, NY); Hewson, John C.; Yoon, Sam Sukgoo
2005-03-01T23:59:59.000Z
This study compares experimental measurements and numerical simulations of liquid droplets over heated (to a near surface temperature of 423 K) and unheated cylinders. The numerical model is based on an unsteady Reynolds-averaged Navier-Stokes (RANS) formulation using a stochastic separated flow (SSF) approach for the droplets that includes submodels for droplet dispersion, heat and mass transfer, and impact on a solid surface. The details of the droplet impact model are presented and the model is used to simulate water spray impingement on a cylinder. Computational results are compared with experimental measurements using phase Doppler interferometry (PDI).
Black liquor combustion validated recovery boiler modeling: Final year report. Volume 5 (Appendix V)
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 5 contains model validation simulations and comparison with data.
A Numerical Model for the Dynamic Simulation of a Recirculation Single-Effect Absorption Chiller
Paris-Sud XI, UniversitÃ© de
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 is developed. The chiller is driven by two distinct heat sources, includes a custom integrated falling film
URBAN AEROSOLS SURVEY USING LIDAR AND NUMERICAL MODEL S. GEFFROY1
Boyer, Edmond
URBAN AEROSOLS SURVEY USING LIDAR AND NUMERICAL MODEL S. GEFFROY1 , L. SOULHAC2 , E. FREJAFON3 , R technologique ALATA BP2, F-60550 Verneuil-en-Halatte, France. Keywords: LIDAR, URBAN AEROSOLS, MODEL, IMPACT SURVEY. INTRODUCTION The impact of particulate matters and aerosols on environment and on radiative
Numerical methods for vector Stefan models of solid-state alloys
Vuik, Kees
-called aluminium-based alloys. Subsequently, the obtained alloy is cast into a mould where it solidifies. DuringNumerical methods for vector Stefan models of solid-state alloys PROEFSCHRIFT ter verkrijging van for vector Stefan models of solid-state alloys. Dissertation at Delft University of Technology. Copyright c
NUMERICAL MODELING OF SHOCK-INDUCED DAMAGE FOR GRANITE UNDER DYNAMIC LOADING
Stewart, Sarah T.
NUMERICAL MODELING OF SHOCK-INDUCED DAMAGE FOR GRANITE UNDER DYNAMIC LOADING H. A. Ai1 , T. J beneath impact crater in granite. Model constants are determined either directly from static uniaxial from Century Dynamics to simulate the shock-induced damage in granite targets impacted by projectiles
Gracie, Robert
PeerReview Only An XFEM Model for Carbon Sequestration Journal: International Journal for Numerical method, Carbon Sequestration, Multiphase flow, XFEM, Multifield systems, Petrov-Galerkin httpScience (www.interscience.wiley.com). DOI: 10.1002/nme An XFEM Model for Carbon Sequestration Chris Ladubec
Nick, F. M.; van der Veen, Cornelis J.; Oerlemans, J.
2007-07-11T23:59:59.000Z
A one-dimensional numerical ice flow model is used to study the advance of a tidewater glacier into deep water. Starting with ice-free conditions, the model simulates glacier growth at higher elevations followed by advance on land to the head...
FOUNDATION, ANALYSIS, AND NUMERICAL INVESTIGATION OF A VARIATIONAL NETWORK-BASED MODEL FOR RUBBER
Boyer, Edmond
FOUNDATION, ANALYSIS, AND NUMERICAL INVESTIGATION OF A VARIATIONAL NETWORK-BASED MODEL FOR RUBBER, many models based on polymer chain statistics have been proposed to describe rubber elasticity. Recently, Alicandro, Cicalese, and the first author rigorously derived a continuum theory of rubber
NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON LARGE TIME STEP OPERATOR SPLITTING ALGORITHMS
processes. A black-oil model is commonly used to describe water injection. This model works well. Special focus is posed on the numerical solution algorithms for the saturation equation, which is a convection dominated, degenerate convection-di#11;usion equation. Both theory and applications are discussed
A Model and Numerical Framework for the Simulation of Solid-Solid Phase Transformations
Govindjee, Sanjay
A Model and Numerical Framework for the Simulation of Solid-Solid Phase Transformations Garrett J computational realization for the simulation of solid-solid phase transformations of the type observed in shape physical experiments and is indicative of the power of the proposed modelling methodology. In particular
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow
Boyer, Edmond
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S modeling of the turbulent flow in a rotor-stator cavity subjected to a superimposed throughflow with heat the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial
MODELING AND ADAPTIVE NUMERICAL TECHNIQUES FOR OXI-DATION OF CERAMIC COMPOSITES
Adjerid, Slimane
. INTRODUCTION Oxidation shortens the life of ceramic matrix composites by, e.g., chang- ing the elasticMODELING AND ADAPTIVE NUMERICAL TECHNIQUES FOR OXI- DATION OF CERAMIC COMPOSITES S. Adjerid, M. Ai of thermal or other loading may expose the matrix and bers to hostile envi- ronments. We present a model
Numerical Modeling of Nonlinear Surface Waves caused by Surface Effect Ships Dynamics and Kinematics
Grilli, StÃ©phan T.
Numerical Modeling of Nonlinear Surface Waves caused by Surface Effect Ships Dynamics and Kinematics Hong Gun SungÂ½ and Stephan T. GrilliÂ¾ Â½ Korea Ocean Research and Development Institute, Daejeon model fully nonlinear free surface waves caused by a translating dis- turbance made of a pressure patch
Concrete calcium leaching at variable temperature: experimental data and numerical model inverse
Paris-Sud XI, UniversitÃ© de
, concrete porous solution is very basic (pH around 13) and several ionic species are highly concentrated [1Concrete calcium leaching at variable temperature: experimental data and numerical model inverse/DSU/SSIAD/BERIS, Fontenay-aux-Roses, France Abstract A simplified model for calcium leaching in concrete is presented
Numerical modeling of response of monolithic and bilayer plates to impulsive loads
Nemat-Nasser, Sia
-receiving side) amplifies the initial shock loading and thereby enhances the destructive effect of the blast modeling FEM analysis Metal-elastomer adhesion Numerical blast modeling a b s t r a c t In this paper, we in the latter case the pressure effects. Comparing the simulation and the experimental results, we focus
d'OrlÃ©ans, UniversitÃ©
processes widely used in chemical engineering: distillation and chromatography. Distillation is a wellNumerical comparison between relaxation and nonlinear equilibrium models. Application to chemical engineering. F. James 1 M. Postel 2 M. Sep'ulveda 3 Abstract A model to take into account the finite exchange
Numerical modeling of fiber lasers with long and ultra-long ring cavity
Turitsyn, Sergei K.
Numerical modeling of fiber lasers with long and ultra-long ring cavity I.A. Yarutkina,1,2, O. S. Kobtsev, S. Kukarin, and Y. Fedotov, "Ultra-low repetition rate mode-locked fiber laser with high highlight two important aspects related to a mathematical modeling of pulsed fiber lasers with long
A consistent modelling methodology for secondary settling tanks: a reliable numerical method
Bürger, Raimund
accounting for sediment compressibility, and a dispersion term for turbulence. In addition, the solutionA consistent modelling methodology for secondary settling tanks: a reliable numerical method modelling methodology for secondary settling tanks (SSTs) leads to a partial differential equation (PDE
Thermal Modeling and Experimental Validation of Human Hair and Skin Heated by Broadband Light
Aguilar, Guillermo
distribution within the hair follicle is highly non-uniform: the minimum temperature occurs at the follicle Sun, PhD,1 Alex Chaney,1 Robert Anderson, PhD,2 and Guillermo Aguilar, PhD 1 * 1 Department:(a)determinetheoveralleffectofPPxonskinhumidi- tyandassociatedskinopticalproperties,and;(b)developaPT numerical model to study the spatial and temporal hair and skin temperature
User's Manual for Data for Validating Models for PV Module Performance
Marion, W.; Anderberg, A.; Deline, C.; Glick, S.; Muller, M.; Perrin, G.; Rodriguez, J.; Rummel, S.; Terwilliger, K.; Silverman, T. J.
2014-04-01T23:59:59.000Z
This user's manual describes performance data measured for flat-plate photovoltaic (PV) modules installed in Cocoa, Florida, Eugene, Oregon, and Golden, Colorado. The data include PV module current-voltage curves and associated meteorological data for approximately one-year periods. These publicly available data are intended to facilitate the validation of existing models for predicting the performance of PV modules, and for the development of new and improved models. For comparing different modeling approaches, using these public data will provide transparency and more meaningful comparisons of the relative benefits.
Incorporation of the capillary hysteresis model HYSTR into the numerical code TOUGH
Niemi, A.; Bodvarsson, G.S.; Pruess, K.
1991-11-01T23:59:59.000Z
As part of the work performed to model flow in the unsaturated zone at Yucca Mountain Nevada, a capillary hysteresis model has been developed. The computer program HYSTR has been developed to compute the hysteretic capillary pressure -- liquid saturation relationship through interpolation of tabulated data. The code can be easily incorporated into any numerical unsaturated flow simulator. A complete description of HYSTR, including a brief summary of the previous hysteresis literature, detailed description of the program, and instructions for its incorporation into a numerical simulator are given in the HYSTR user`s manual (Niemi and Bodvarsson, 1991a). This report describes the incorporation of HYSTR into the numerical code TOUGH (Transport of Unsaturated Groundwater and Heat; Pruess, 1986). The changes made and procedures for the use of TOUGH for hysteresis modeling are documented.
Blackman, Jonathan; Galley, Chad R; Szilagyi, Bela; Scheel, Mark A; Tiglio, Manuel; Hemberger, Daniel A
2015-01-01T23:59:59.000Z
Simulating a binary black hole coalescence by solving Einstein's equations is computationally expensive, requiring days to months of supercomputing time. In this paper, we construct an accurate and fast-to-evaluate surrogate model for numerical relativity (NR) waveforms from non-spinning binary black hole coalescences with mass ratios from $1$ to $10$ and durations corresponding to about $15$ orbits before merger. Our surrogate, which is built using reduced order modeling techniques, is distinct from traditional modeling efforts. We find that the full multi-mode surrogate model agrees with waveforms generated by NR to within the numerical error of the NR code. In particular, we show that our modeling strategy produces surrogates which can correctly predict NR waveforms that were {\\em not} used for the surrogate's training. For all practical purposes, then, the surrogate waveform model is equivalent to the high-accuracy, large-scale simulation waveform but can be evaluated in a millisecond to a second dependin...
Characterization of Texas lignite and numerical modeling of its in-situ gasification
Wang, Yih-Jy
1983-01-01T23:59:59.000Z
Modeling Site selection for in-situ gasification projects normally involves application of site screen1ng criteria. Some of these cr1teria were discussed by Russell et al. (1983). Numerical simulation may play an important role in s1te selection...CHARACTERIZATION OF TEXAS LIGNITE AND NUMERICAL MODELING OF ITS IN-SITU GASIFICATION A Thesis by YIH-JY WANG Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER...
The numerical solution of a nickel-cadmium battery cell model using the method of lines
Hailu, Teshome
1990-01-01T23:59:59.000Z
THE NUMERICAL SOLUTION OF A NICKEL-CADMIUM BATTERY CELL MODEL USING THE METHOD OF LINES A Thesis by TESHOME HAILU Submitted to the Office of Graduate Studies Texas Adi:M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1990 Major Subject: Chemical Engineering THE NUMERICAL SOLUTION OF A NICKEL-CADMIUM BATTERY CELL MODEL USING THE METHOD OF LINES A Thesis by TESHOME HAILU Approved as to style and content by: Ralph E. White (Chairman...
Proceedings of the Numerical Modeling for Underground Nuclear Test Monitoring Symposium
Taylor, S.R.; Kamm, J.R. [eds.
1993-11-01T23:59:59.000Z
The purpose of the meeting was to discuss the state-of-the-art in numerical simulations of nuclear explosion phenomenology with applications to test ban monitoring. We focused on the uniqueness of model fits to data, the measurement and characterization of material response models, advanced modeling techniques, and applications of modeling to monitoring problems. The second goal of the symposium was to establish a dialogue between seismologists and explosion-source code calculators. The meeting was divided into five main sessions: explosion source phenomenology, material response modeling, numerical simulations, the seismic source, and phenomenology from near source to far field. We feel the symposium reached many of its goals. Individual papers submitted at the conference are indexed separately on the data base.
Nguyen, Ba Nghiep; Jin, Xiaoshi; Wang, Jin; Kunc, Vlastimil; Tucker III, Charles L.
2012-02-23T23:59:59.000Z
This report describes the work conducted under the CRADA Nr. PNNL/304 between Battelle PNNL and Autodesk whose objective is to validate the new process models developed under the previous CRADA for large injection-molded LFT composite structures. To this end, the ARD-RSC and fiber length attrition models implemented in the 2013 research version of Moldflow was used to simulate the injection molding of 600-mm x 600-mm x 3-mm plaques from 40% glass/polypropylene (Dow Chemical DLGF9411.00) and 40% glass/polyamide 6,6 (DuPont Zytel 75LG40HSL BK031) materials. The injection molding was performed by Injection Technologies, Inc. at Windsor, Ontario (under a subcontract by Oak Ridge National Laboratory, ORNL) using the mold offered by the Automotive Composite Consortium (ACC). Two fill speeds under the same back pressure were used to produce plaques under slow-fill and fast-fill conditions. Also, two gating options were used to achieve the following desired flow patterns: flows in edge-gated plaques and in center-gated plaques. After molding, ORNL performed measurements of fiber orientation and length distributions for process model validations. The structure of this report is as follows. After the Introduction (Section 1), Section 2 provides a summary of the ARD-RSC and fiber length attrition models. A summary of model implementations in the latest research version of Moldflow is given in Section 3. Section 4 provides the key processing conditions and parameters for molding of the ACC plaques. The validations of the ARD-RSC and fiber length attrition models are presented and discussed in Section 5. The conclusions will be drawn in Section 6.
Anh Bui; Nam Dinh; Brian Williams
2013-09-01T23:59:59.000Z
In addition to validation data plan, development of advanced techniques for calibration and validation of complex multiscale, multiphysics nuclear reactor simulation codes are a main objective of the CASL VUQ plan. Advanced modeling of LWR systems normally involves a range of physico-chemical models describing multiple interacting phenomena, such as thermal hydraulics, reactor physics, coolant chemistry, etc., which occur over a wide range of spatial and temporal scales. To a large extent, the accuracy of (and uncertainty in) overall model predictions is determined by the correctness of various sub-models, which are not conservation-laws based, but empirically derived from measurement data. Such sub-models normally require extensive calibration before the models can be applied to analysis of real reactor problems. This work demonstrates a case study of calibration of a common model of subcooled flow boiling, which is an important multiscale, multiphysics phenomenon in LWR thermal hydraulics. The calibration process is based on a new strategy of model-data integration, in which, all sub-models are simultaneously analyzed and calibrated using multiple sets of data of different types. Specifically, both data on large-scale distributions of void fraction and fluid temperature and data on small-scale physics of wall evaporation were simultaneously used in this work’s calibration. In a departure from traditional (or common-sense) practice of tuning/calibrating complex models, a modern calibration technique based on statistical modeling and Bayesian inference was employed, which allowed simultaneous calibration of multiple sub-models (and related parameters) using different datasets. Quality of data (relevancy, scalability, and uncertainty) could be taken into consideration in the calibration process. This work presents a step forward in the development and realization of the “CIPS Validation Data Plan” at the Consortium for Advanced Simulation of LWRs to enable quantitative assessment of the CASL modeling of Crud-Induced Power Shift (CIPS) phenomenon, in particular, and the CASL advanced predictive capabilities, in general. This report is prepared for the Department of Energy’s Consortium for Advanced Simulation of LWRs program’s VUQ Focus Area.
:,; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corpuz, A; Corsi, A; Costa, C A; Coughlin, M W; Coughlin, S; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; Donath, A; Donovan, F; Dooley, K L; Doravari, S; Dossa, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dwyer, S; Eberle, T; Edo, T; Edwards, M; Effler, A; Eggenstein, H; Ehrens, P; Eichholz, J; Eikenberry, S S; Endr?czi, G; Essick, R; Etzel, T; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fehrmann, H; Fejer, M M; Feldbaum, D; Feroz, F; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Gaonkar, S; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Gräf, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Groot, P; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K; Gustafson, E K; Gustafson, R; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hart, M; Hartman, M T; Haster, C -J; Haughian, K; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hooper, S; Hopkins, P; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jaranowski, P; Ji, Y; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karlen, J; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawazoe, F; Kéfélian, F; Keiser, G M; Keitel, D; Kelley, D B; Kells, W; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, C; Kim, K; Kim, N; Kim, N G; Kim, Y -M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K; Kondrashov, V; Koranda, S; Korth, W Z; Kowalska, I
2014-01-01T23:59:59.000Z
The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave astrophysics communities. The purpose of NINJA is to study the ability to detect gravitational waves emitted from merging binary black holes and recover their parameters with next-generation gravitational-wave observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete binary black hole hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a "blind injection challenge" similar to that conducted in recent LIGO and Virgo science runs, we added 7 hybrid waveforms to two months of data recolored to predictions of Advanced LIGO and Advanced Virgo sensitivity curves during their first observing runs. The resulting data was analyzed by gravitational-wave detection algorithms and 6 of the waveforms were recovered w...
Validity of pair truncation of the nuclear shell model in {sup 46}Ca
Lei, Y.; Xu, Z. Y. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhao, Y. M. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 (China); CCAST, World Laboratory, Post Office Box 8730, Beijing 100080 (China); Arima, A. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Science Museum, Japan Science Foundation, 2-1 Kitanomaru-koen, Chiyoda-ku, Tokyo 102-0091 (Japan)
2009-12-15T23:59:59.000Z
We study the validity of pair truncation of the nuclear shell model by using the semimagic nucleus {sup 46}Ca. We present low-lying states and their E2 transition rates based on both nucleon pair approximation (NPA) and exact shell-model (SM) calculations. We also calculate overlaps between wave functions of low-lying states calculated by using the NPA and those calculated by using the SM. Our calculated results show a remarkable agreement between the NPA results and the SM results, although the NPA is a drastic truncation of the SM.
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 1 contains the main body of the report and the first 4 sections of Appendix 1: Modeling of black liquor recovery boilers -- summary report; Flow and heat transfer modeling in the upper furnace of a kraft recovery boiler; Numerical simulation of black liquor combustion; and Investigation of turbulence models and prediction of swirling flows for kraft recovery furnaces.
Numerical Modeling of Hydro-acoustic Waves In Weakly Compressible Fluid Ali Abdolali1,2
Kirby, James T.
Numerical Modeling of Hydro-acoustic Waves In Weakly Compressible Fluid Ali Abdolali1,2 , James T of Civil Engineering, University of Roma Tre Low-frequency hydro-acoustic waves are precursors of tsunamis. Detection of hydro-acoustic waves generated due to the water column compression triggered by sudden seabed
January 2, 2008 Numerical modeling of the effect of carbon dioxide
Boyer, Edmond
January 2, 2008 Numerical modeling of the effect of carbon dioxide sequestration on the rate souterrain de dioxyde de carbone sur la déformation des calcaires par dissolution sous contrainte: résultats;Abstract When carbon dioxide (CO2) is injected into an aquifer or a depleted geological reservoir, its
Numerical Modelling of Unsaturated Flow in Uniform and Heterogeneous Waste Rock Piles
Aubertin, Michel
Numerical Modelling of Unsaturated Flow in Uniform and Heterogeneous Waste Rock Piles O Fala1 , M Aubertin1,3 , J Molson1 , B Bussière2,3 , G W Wilson4 , R Chapuis1 and V Martin1 ABSTRACT Waste rock piles these piles, many physical, geochemical and biological processes can contribute to the production of AMD
Numerical methods for the simulation of a corrosion model in a nuclear waste deep repository $
Paris-Sud XI, Université de
Numerical methods for the simulation of a corrosion model in a nuclear waste deep repository $ C of the French nuclear waste management agency ANDRA, investigations are conducted to optimize and finalize by the Nuclear Waste Management Agency ANDRA Corresponding author. Phone: +49 30 20372 560, Fax: +49 30 2044975
Numerical analysis of electric field formulations of the eddy current model
RodrÃguez, Rodolfo
Numerical analysis of electric field formulations of the eddy current model Alfredo BermÂ´udez1 methods for the numeri- cal solution of the eddy current problem in a bounded conducting domain crossed): 78M10, 65N30 Key words Low-frequency harmonic Maxwell equations, eddy currents, finite elements
Mathematical and numerical analysis of a transient non-linear axisymmetric eddy current model
RodrÃguez, Rodolfo
Mathematical and numerical analysis of a transient non-linear axisymmetric eddy current model the theoretically predicted behavior of the method, are reported. Keywords transient eddy current Â· axisymmetric is the accurate computation of power losses in the ferromagnetic components of the core due to hysteresis and eddy-current
NUMERICAL SOLUTION OF A TRANSIENT NON-LINEAR AXISYMMETRIC EDDY CURRENT MODEL WITH NON-LOCAL
RodrÃguez, Rodolfo
NUMERICAL SOLUTION OF A TRANSIENT NON-LINEAR AXISYMMETRIC EDDY CURRENT MODEL WITH NON@ing-mat.udec.cl This paper deals with an axisymmetric transient eddy current problem in conductive nonlinear magnetic media of the proposed scheme. Keywords: transient eddy current problem; electromagnetic losses; nonlinear magnetic
A simple numerical model of the apparent loss of eddy current conductivity due to surface roughness
Nagy, Peter B.
A simple numerical model of the apparent loss of eddy current conductivity due to surface roughness of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation, the path of the eddy current must follow a more tortuous route in the material, which produces a reduction
Ensemble Kalman Filter Data Assimilation in a 1D Numerical Model Used for Fog Forecasting
Ribes, Aurélien
Ensemble Kalman Filter Data Assimilation in a 1D Numerical Model Used for Fog Forecasting SAMUEL RE significant. This led to the implementation of an ensemble Kalman filter (EnKF) within COBEL-ISBA. The new by using an ensemble Kalman filter (EnKF; Evensen 1994, 2003). Theoreti- cally, ensemble filters
LABORATORY OBSERVATIONS AND NUMERICAL MODELING OF THE EFFECTS OF AN ARRAY OF WAVE ENERGY CONVERTERS
Haller, Merrick
1 LABORATORY OBSERVATIONS AND NUMERICAL MODELING OF THE EFFECTS OF AN ARRAY OF WAVE ENERGY of wave energy converters (WECs) on water waves through the analysis of extensive laboratory experiments absorption is a reasonable predictor of the effect of WECs on the far field. Keywords: wave- energy; spectral
A numerical modeling study on desert oasis self-supporting mechanisms
Chu, Peter C.
A numerical modeling study on desert oasis self-supporting mechanisms Peter C. Chua, *, Shihua Lub February 2005 Abstract Oasis self-supporting mechanisms due to oasis breeze circulation (OBC) are proposed from the oasis makes the oasis surface colder than the surrounding desert surface. The sensible heat
September 25, 2006 Numerical modeling of the effect of carbon dioxide
Paris-Sud XI, Université de
September 25, 2006 Numerical modeling of the effect of carbon dioxide sequestration on the rate souterrain de dioxyde de carbone sur la déformation des calcaires par dissolution sous contrainte: résultats@obs.ujf- grenoble.fr, marielle.collombet@ujf-grenoble.fr, yleguen@lgit.obs.ujf-grenoble.fr. #12;Abstract When carbon
COMPUTATIONAL CHALLENGES IN THE NUMERICAL TREATMENT OF LARGE AIR POLLUTION MODELS
Dimov, Ivan
COMPUTATIONAL CHALLENGES IN THE NUMERICAL TREATMENT OF LARGE AIR POLLUTION MODELS I. DIMOV , K. GEORGIEVy, TZ. OSTROMSKY , R. J. VAN DER PASz, AND Z. ZLATEVx Abstract. The air pollution, and especially the reduction of the air pollution to some acceptable levels, is an important environmental problem, which
Nonlinear inverse problem for a model of ion-exchange filter: numerical recovery of parameters
) and pressure (15 MPa) of hot steam [2]. Some units are made of cheap corrosion and heat-resistant steel which1 Nonlinear inverse problem for a model of ion-exchange filter: numerical recovery of parameters]. Power-generating units of TPP operate under severe corrosive conditions: high temperature (515 - 530°C
NUMERICAL MODELLING OF THERMAL-ELECTRICAL PHENOMENA IN SPARK PLASMA SINTERING
Boyer, Edmond
NUMERICAL MODELLING OF THERMAL-ELECTRICAL PHENOMENA IN SPARK PLASMA SINTERING P. Mondaleka , L'Etudes Structurales), France c Université Paul Sabatier, Toulouse, France Abstract. Spark Plasma Sintering belongs: Finite element method, Spark plasma sintering, powder compaction. INTRODUCTION Spark Plasma Sintering
A numerical ocean circulation model of the Norwegian and Greenland Seas
Stevens, David
A numerical ocean circulation model of the Norwegian and Greenland Seas DAVID P STEVENS School of the Norwegian and Greenland Seas are investigated using a three-dimensional primitive equation ocean circulation and seasonally varying wind and thermohalme forcing. The connections of the Norwegian and Greenland Seas
Numerical Solution of Two Asset Jump Diffusion Models for Option Valuation
Forsyth, Peter A.
Numerical Solution of Two Asset Jump Diffusion Models for Option Valuation Simon S. Clift and Peter parabolic partial integro-differential equation (PIDE). An implicit, finite difference method is derived with an FFT. The method prices both American and European style contracts indepen- dent (under some simple
Boyer, Edmond
A LARGE SCALE CONTINUUM-DISCRETE NUMERICAL MODELLING: APPLICATION TO OVERBURDEN DAMAGE OF A SALT damage on top of an underground solution mining, an in-situ experiment is undertaken above a salt cavity in the Lorraine region (NE of France). The overburden overlying the salt cavity is characterized by a competent
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow
Boyer, Edmond
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis
Aguilar, Guillermo
Numerical modeling of spray cooling-assisted dermatologic laser surgery for treatment of port wine to the epidermis during dermatologic laser surgery (DLS) for removal of port wine stain (PWS) birthmarks heat (J/kg/K) c speed of light in i (m/s) D optical diffusion coefficient (m) Ea activation energy
3 Response to comment by Jozsef Szilagyi on 4 ``Using numerical modelling to evaluate the
McDonnell, Jeffrey J.
REPLY 3 Response to comment by Jozsef Szilagyi on 4 ``Using numerical modelling to evaluate the 5 by Szilagyi is a welcome addition to the de- 15 bate surrounding the link between the hypothesis of 16 a possible explanation for high proportions of 40pre-event water. 41Szilagyi (submitted) has identified
Numerical modelling of avalanches based on Saint-Venant equations using a kinetic scheme
Paris-Sud XI, Université de
avalanches are treated here as a dry granular flow with Coulomb-type behavior. The numerical finite volume of an avalanche over simplified topography. Coulomb-type behavior with constant and variable friction angle modelling, Coulomb friction, Saint-Venant equations, finite volume kinetic scheme. 1 Introduction Granular
NUMERICAL MODELLING OF AUTOGENOUS HEALING AND RECOVERY OF MECHANICAL PROPERTIES IN ULTRA-HIGH
Boyer, Edmond
in the cementitious matrix can react with carbon dioxide dissolved in the water filling the crack. Autogenous healingNUMERICAL MODELLING OF AUTOGENOUS HEALING AND RECOVERY OF MECHANICAL PROPERTIES IN ULTRA into the crack and leads to a partial recovery of mechanical properties (Young's modulus, tensile strength
Mathematical, physical and numerical principles essential for models of turbulent mixing
Sharp, David Howland [Los Alamos National Laboratory; Lim, Hyunkyung [STONY BROOK UNIV; Yu, Yan [STONY BROOK UNIV; Glimm, James G [STONY BROOK UNIV
2009-01-01T23:59:59.000Z
We propose mathematical, physical and numerical principles which are important for the modeling of turbulent mixing, especially the classical and well studied Rayleigh-Taylor and Richtmyer-Meshkov instabilities which involve acceleration driven mixing of a fluid discontinuity layer, by a steady accerleration or an impulsive force.
Wells, Scott A.
792 / JOURNAL OF ENVIRONMENTAL ENGINEERING / SEPTEMBER 1999 NUMERICAL MODEL OF SEDIMENTATION with the ASCE Manager of Journals. The manuscript for this paper was submitted for review and possible publication on July 20, 1998. This paper is part of the Journal of Environmental Engineering, Vol. 125, No. 9
The Hamiltonian Particle-Mesh (HPM) method for numerical modeling of atmospheric flows.
Kim, Guebuem
The Hamiltonian Particle-Mesh (HPM) method for numerical modeling of atmospheric flows. Seoleun Shin 15. Feb. 2011 Abstract The Hamiltonian Particle-Mesh (HPM) method is an interesting alternative have developed schemes based on the HPM method for the shallow-water equations on the sphere, nonhydro
Couling, A. J.; Goupee, A. J.; Robertson, A. N.; Jonkman, J. M.
2013-06-01T23:59:59.000Z
To better access the abundant offshore wind resource, efforts across the world are being undertaken to develop and improve floating offshore wind turbine technologies. A critical aspect of creating reliable, mature floating wind turbine technology is the development, verification, and validation of efficient computer-aided-engineering (CAE) tools that can be relied upon in the design process. The National Renewable Energy Laboratory (NREL) has created a comprehensive, coupled analysis CAE tool for floating wind turbines, FAST, which has been verified and utilized in numerous floating wind turbine studies. Several efforts are currently underway that leverage the extensive 1/50th-scale DeepCwind wind/wave basin model test dataset, obtained at the Maritime Research Institute Netherlands (MARIN) in 2011, to validate the floating platform functionality of FAST to complement its already validated aerodynamic and structural simulation capabilities. In this paper, further work is undertaken to continue this validation. In particular, the ability of FAST to replicate global response behaviors associated with dynamic wind forces, second-order difference-frequency wave-diffraction forces and their interaction with one another are investigated.
Coclite, A; De Palma, P; Pascazio, G
2015-01-01T23:59:59.000Z
The present paper deals with the numerical study of high pressure LOx/H2 or LOx/hydrocarbon combustion for propulsion systems. The present research effort is driven by the continued interest in achieving low cost, reliable access to space and more recently, by the renewed interest in hypersonic transportation systems capable of reducing time-to-destination. Moreover, combustion at high pressure has been assumed as a key issue to achieve better propulsive performance and lower environmental impact, as long as the replacement of hydrogen with a hydrocarbon, to reduce the costs related to ground operations and increase flexibility. The current work provides a model for the numerical simulation of high- pressure turbulent combustion employing detailed chemistry description, embedded in a RANS equations solver with a Low Reynolds number k-omega turbulence model. The model used to study such a combustion phenomenon is an extension of the standard flamelet-progress-variable (FPV) turbulent combustion model combined ...
Value of Laboratory Experiments for Code Validations
Wawersik, W.R.
1998-12-14T23:59:59.000Z
Numerical codes have become indispensable for designing underground structures and interpretating the behavior of geologic systems. Because of the complexities of geologic systems, however, code calculations often are associated with large quantitative uncertainties. This papers presents three examples to demonstrate the value of laboratory(or bench scale) experiments to evaluate the predictive capabilities of such codes with five major conclusions: Laboratory or bench-scale experiments are a very cost-effective, controlled means of evaluating and validating numerical codes, not instead of but before or at least concurrent with the implementation of in situ studies. The design of good laboratory validation tests must identifj what aspects of a code are to be scrutinized in order to optimize the size, geometry, boundary conditions, and duration of the experiments. The design of good and sometimes difficult numerical analyses and sensitivity studies. Laboratory validation tests must involve: Good validation experiments will generate independent data sets to identify the combined effect of constitutive models, model generalizations, material parameters, and numerical algorithms. Successfid validations of numerical codes mandate a close collaboration between experimentalists and analysts drawing from the full gamut of observations, measurements, and mathematical results.
Building ventilation: A pressure airflow model computer generation and elements of validation
Boyer, H; Adelard, L; Mara, T A
2012-01-01T23:59:59.000Z
The calculation of airflows is of great importance for detailed building thermal simulation computer codes, these airflows most frequently constituting an important thermal coupling between the building and the outside on one hand, and the different thermal zones on the other. The driving effects of air movement, which are the wind and the thermal buoyancy, are briefly outlined and we look closely at their coupling in the case of buildings, by exploring the difficulties associated with large openings. Some numerical problems tied to the resolving of the non-linear system established are also covered. Part of a detailled simulation software (CODYRUN), the numerical implementation of this airflow model is explained, insisting on data organization and processing allowing the calculation of the airflows. Comparisons are then made between the model results and in one hand analytical expressions and in another and experimental measurements in case of a collective dwelling.
Direct Numerical Simulations of the Kraichnan Model: Scaling Exponents and Fusion Rules
Adrienne L. Fairhall; Barak Galanti; Victor S. L'vov; Itamar Procaccia
1997-07-01T23:59:59.000Z
We present results from direct numerical simulations of the Kraichnan model for passive scalar advection by a rapidly-varying random scaling velocity field for intermediate values of the velocity scaling exponent. These results are compared with the scaling exponents predicted for this model by Kraichnan. Further, we test the recently proposed fusion rules which govern the scaling properties of multi-point correlations, and present results on the linearity of the conditional statistics of the Laplacian operator on the scalar field.
Low frequency eddy current finite element model validation and benchmark studies
Cherry, M.; Knopp, J. [Materials and Manufacturing Directorate, Air Force Research Laboratory (United States); Mooers, R.; Boehnlein, T. [University of Dayton Research Institute, Dayton, OH (United States); Aldrin, J. C. [Computational Tools, Gurnee, IL (United States); Sabbagh, H. A. [Victor Technologies, LLC, Bloomington, IN (United States)
2011-06-23T23:59:59.000Z
A finite element method (FEM) model was created to calculate the change in impedance of a coil due to the presence of a notch in a plate. The rectangular notches were created via electrical discharge machining (EDM) in a thick aluminum plate and were positioned at normal and oblique angles (10, 20, and 30 degrees) with respect to the vertical axis of the coil. The FEM method was chosen for this model due to its ability to solve problems in complicated geometries with the use of irregular mesh elements to discretize the solution domain. The change in impedance was calculated from the field variables in the simulation for each probe position along the parallel axis of the plate. The error between the model and the experimental data was approximately 5% for the majority of cases. The validated model was used to investigate more complex problems.
Development and validation of a transition model based on a mechanical approximation
Vizinho, R; Silvestre, M
2015-01-01T23:59:59.000Z
A new 3D transition turbulence model, more accurate and faster than an empirical transition model, is proposed. The model is based on the calculation of the pre-transitional u'v' due to mean flow shear. The present transition model is fully described and verified against eight benchmark test cases. Computations are performed for the ERCOFTAC flat-plate T3A, T3C and T3L test cases. Further, the model is validated for bypass, cross-flow and separation induced transition and compared with empirical transition models. The model presents very good results for bypass transition under zero-pressure gradient and with pressure gradient flow conditions. Also the model is able to correctly predict separation induced transition. However, for very low speed and low free-stream turbulence intensity the model delays separation induced transition onset. The model also shows very good results for transition under complex cross-flow conditions in three-dimensional geometries. The 3D tested case was the 6:1 prolate-spheroid und...
Modelling and Numerical Simulation of Gas Migration in a Nuclear Waste Repository
Bourgeat, Alain; Smai, Farid
2010-01-01T23:59:59.000Z
We present a compositional compressible two-phase, liquid and gas, flow model for numerical simulations of hydrogen migration in deep geological radioactive waste repository. This model includes capillary effects and the gas diffusivity. The choice of the main variables in this model, Total or Dissolved Hydrogen Mass Concentration and Liquid Pressure, leads to a unique and consistent formulation of the gas phase appearance and disappearance. After introducing this model, we show computational evidences of its adequacy to simulate gas phase appearance and disappearance in different situations typical of underground radioactive waste repository.
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 4 contains the following appendix sections: Radiative heat transfer properties for black liquor combustion -- Facilities and techniques and Spectral absorbance and emittance data; and Radiate heat transfer determination of the optical constants of ash samples from kraft recovery boilers -- Calculation procedure; Computation program; Density determination; Particle diameter determination; Optical constant data; and Uncertainty analysis.
Formulation, Implementation and Validation of a Two-Fluid model in a Fuel Cell CFD Code
Kunal Jain, Vernon Cole, Sanjiv Kumar and N. Vaidya
2008-11-01T23:59:59.000Z
Water management is one of the main challenges in PEM Fuel Cells. While water is essential for membrane electrical conductivity, excess liquid water leads to ooding of catalyst layers. Despite the fact that accurate prediction of two-phase transport is key for optimal water management, understanding of the two-phase transport in fuel cells is relatively poor. Wang et. al. [1], [2] have studied the two-phase transport in the channel and diffusion layer separately using a multiphase mixture model. The model fails to accurately predict saturation values for high humidity inlet streams. Nguyen et. al. [3] developed a two-dimensional, two-phase, isothermal, isobaric, steady state model of the catalyst and gas diffusion layers. The model neglects any liquid in the channel. Djilali et. al. [4] developed a three-dimensional two-phase multicomponent model. The model is an improvement over previous models, but neglects drag between the liquid and the gas phases in the channel. In this work, we present a comprehensive two- fluid model relevant to fuel cells. Models for two-phase transport through Channel, Gas Diffusion Layer (GDL) and Channel-GDL interface, are discussed. In the channel, the gas and liquid pressures are assumed to be same. The surface tension effects in the channel are incorporated using the continuum surface force (CSF) model. The force at the surface is expressed as a volumetric body force and added as a source to the momentum equation. In the GDL, the gas and liquid are assumed to be at different pressures. The difference in the pressures (capillary pressure) is calculated using an empirical correlations. At the Channel-GDL interface, the wall adhesion affects need to be taken into account. SIMPLE-type methods recast the continuity equation into a pressure-correction equation, the solution of which then provides corrections for velocities and pressures. However, in the two-fluid model, the presence of two phasic continuity equations gives more freedom and more complications. A general approach would be to form a mixture continuity equation by linearly combining the phasic continuity equations using appropriate weighting factors. Analogous to mixture equation for pressure correction, a difference equation is used for the volume/phase fraction by taking the difference between the phasic continuity equations. The relative advantages of the above mentioned algorithmic variants for computing pressure correction and volume fractions are discussed and quantitatively assessed. Preliminary model validation is done for each component of the fuel cell. The two-phase transport in the channel is validated using empirical correlations. Transport in the GDL is validated against results obtained from LBM and VOF simulation techniques. The Channel-GDL interface transport will be validated against experiment and empirical correlation of droplet detachment at the interface. References [1] Y. Wang S. Basu and C.Y. Wang. Modeling two-phase flow in pem fuel cell channels. J. Power Sources, 179:603{617, 2008. [2] P. K. Sinha and C. Y. Wang. Liquid water transport in a mixed-wet gas diffusion layer of a polymer electrolyte fuel cell. Chem. Eng. Sci., 63:1081-1091, 2008. [3] Guangyu Lin and Trung Van Nguyen. A two-dimensional two-phase model of a pem fuel cell. J. Electrochem. Soc., 153(2):A372{A382, 2006. [4] T. Berning and N. Djilali. A 3d, multiphase, multicomponent model of the cathode and anode of a pem fuel cell. J. Electrochem. Soc., 150(12):A1589{A1598, 2003.
Laboratory experiments and numerical modeling of wave attenuation through artificial vegetation
Augustin, Lauren Nicole
2009-05-15T23:59:59.000Z
). The first hydrodynamic model developed by Price et al. (1968) simulated the effects of seaweed as a high viscous layer. Mork (1996) extended the idea of the high viscous layer and developed a theory for kelp plants that took into account not only viscous... has been validated by artificial laboratory kelp experiments for the species Laminaria Hyperborea, and is assumed appropriate for representing wave transformation and damping over submerged vegetative fields of variable depths. Mork (1996) studied...
Slepoy, Alexander; Mitchell, Scott A.; Backus, George A.; McNamara, Laura A.; Trucano, Timothy Guy
2008-09-01T23:59:59.000Z
Sandia National Laboratories is investing in projects that aim to develop computational modeling and simulation applications that explore human cognitive and social phenomena. While some of these modeling and simulation projects are explicitly research oriented, others are intended to support or provide insight for people involved in high consequence decision-making. This raises the issue of how to evaluate computational modeling and simulation applications in both research and applied settings where human behavior is the focus of the model: when is a simulation 'good enough' for the goals its designers want to achieve? In this report, we discuss two years' worth of review and assessment of the ASC program's approach to computational model verification and validation, uncertainty quantification, and decision making. We present a framework that extends the principles of the ASC approach into the area of computational social and cognitive modeling and simulation. In doing so, we argue that the potential for evaluation is a function of how the modeling and simulation software will be used in a particular setting. In making this argument, we move from strict, engineering and physics oriented approaches to V&V to a broader project of model evaluation, which asserts that the systematic, rigorous, and transparent accumulation of evidence about a model's performance under conditions of uncertainty is a reasonable and necessary goal for model evaluation, regardless of discipline. How to achieve the accumulation of evidence in areas outside physics and engineering is a significant research challenge, but one that requires addressing as modeling and simulation tools move out of research laboratories and into the hands of decision makers. This report provides an assessment of our thinking on ASC Verification and Validation, and argues for further extending V&V research in the physical and engineering sciences toward a broader program of model evaluation in situations of high consequence decision-making.
Black Liquor Combustion Validated Recovery Boiler Modeling, Final Year Report, Volume 5: Appendix V
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990 with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. Many of these objectives were accomplished at the end of the first five years and documented in a comprehensive report on that work (DOE/CE/40936-T3, 1996). A critical review of recovery boiler modeling, carried out in 1995, concluded that further enhancements of the model were needed to make reliable predictions of key output variables. In addition, there was a need for sufficient understanding of fouling and plugging processes to allow model outputs to be interpreted in terms of the effect on plugging and fouling. As a result, the project was restructured and reinitiated at the end of October 1995, and was completed in June 1997. The entire project is now complete and this report summarizes all of the work done on the project since it was restructured. The key tasks to be accomplished under the restructured project were to (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes; (2) Validate the enhanced furnace models, so that users can have confidence in the results; (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler; and (4) Facilitate the transfer of codes, black liquor submodels, and fundamental knowledge to the U.S. kraft pulp industry.
Black Liquor Combustion Validated Recovery Boiler Modeling, Final Year Report, Volume 4: Appendix IV
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990 with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. Many of these objectives were accomplished at the end of the first five years and documented in a comprehensive report on that work (DOE/CE/40936-T3, 1996). A critical review of recovery boiler modeling, carried out in 1995, concluded that further enhancements of the model were needed to make reliable predictions of key output variables. In addition, there was a need for sufficient understanding of fouling and plugging processes to allow model outputs to be interpreted in terms of the effect on plugging and fouling. As a result, the project was restructured and reinitiated at the end of October 1995, and was completed in June 1997. The entire project is now complete and this report summarizes all of the work done on the project since it was restructured. The key tasks to be accomplished under the restructured project were to (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes; (2) Validate the enhanced furnace models, so that users can have confidence in the results; (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler; and (4) Facilitate the transfer of codes, black liquor submodels, and fundamental knowledge to the U.S. kraft pulp industry.
Garcia-Hiraldo, Roberto
1990-01-01T23:59:59.000Z
University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1990 Major Subject: Meteorology VALIDATION STUDY OF A MULTIDIMENSIONAL HYDROLOGIC MODEL OF RAINFALL, AND THE SIMULATION OF OROGRAPHIC INFLUENCES, USING... University of P. R. Co-Chairs of Advisory Committee: Dr. Dennis M. Driscoll Dr. Juan B. Valdes The main purpose of this research was validate an existing multidimensional stochastic hydrologic model of precipitation, which attempts to characterize...
Billman, L.; Keyser, D.
2013-08-01T23:59:59.000Z
The Jobs and Economic Development Impacts (JEDI) models, developed by the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), use input-output methodology to estimate gross (not net) jobs and economic impacts of building and operating selected types of renewable electricity generation and fuel plants. This analysis provides the DOE with an assessment of the value, impact, and validity of the JEDI suite of models. While the models produce estimates of jobs, earnings, and economic output, this analysis focuses only on jobs estimates. This validation report includes an introduction to JEDI models, an analysis of the value and impact of the JEDI models, and an analysis of the validity of job estimates generated by JEDI model through comparison to other modeled estimates and comparison to empirical, observed jobs data as reported or estimated for a commercial project, a state, or a region.
Development and Validation of an Aeroelastic Model of a Small Furling Wind Turbine: Preprint
Jonkman, J. M.; Hansen, A. C.
2004-12-01T23:59:59.000Z
Small wind turbines often use some form of furling (yawing and/or tilting out of the wind) to protect against excessive power generation and rotor speeds in high winds.The verification study demonstrated the correct implementation of FAST's furling dynamics. During validation, the model tends to predict mean rotor speeds higher than measured in spite of the fact that the mean furl motion and rotor thrust are predicted quite accurately. This work has culminated with an enhanced version of FAST that should prove to be a valuable asset to designers of small wind turbines.
Dynamic Model Validation of PV Inverters Under Short-Circuit Conditions: Preprint
Muljadi, E.; Singh, M.; Bravo, R.; Gevorgian, V.
2013-03-01T23:59:59.000Z
Photovoltaic (PV) modules have dramatically decreased in price in the past few years, spurring the expansion of photovoltaic deployment. Residential and commercial rooftop installations are connected to the distribution network; large-scale installation PV power plants (PVPs) have benefited from tax incentives and the low cost of PV modules. As the level penetration of PV generation increases, the impact on power system reliability will also be greater. Utility power system planners must consider the role of PV generation in power systems more realistically by representing PV generation in dynamic stability analyses. Dynamic models of PV inverters have been developed in the positive sequence representation. NREL has developed a PV inverter dynamic model in PSCAD/EMTDC. This paper validates the dynamic model with an actual hardware bench test conducted by Southern California Edison's Distributed Energy Resources laboratory. All the fault combinations -- symmetrical and unsymmetrical -- were performed in the laboratory. We compare the simulation results with the bench test results.
Experiments to populate and validate a processing model for polyurethane foam :
Mondy, Lisa Ann; Rao, Rekha Ranjana; Shelden, Bion; Soehnel, Melissa Marie; O'Hern, Timothy J.; Grillet, Anne; Celina, Mathias Christopher; Wyatt, Nicholas B.; Russick, Edward Mark; Bauer, Stephen J.; Hileman, Michael Bryan; Urquhart, Alexander; Thompson, Kyle Richard; Smith, David Michael
2014-03-01T23:59:59.000Z
We are developing computational models to elucidate the expansion and dynamic filling process of a polyurethane foam, PMDI. The polyurethane of interest is chemically blown, where carbon dioxide is produced via the reaction of water, the blowing agent, and isocyanate. The isocyanate also reacts with polyol in a competing reaction, which produces the polymer. Here we detail the experiments needed to populate a processing model and provide parameters for the model based on these experiments. The model entails solving the conservation equations, including the equations of motion, an energy balance, and two rate equations for the polymerization and foaming reactions, following a simplified mathematical formalism that decouples these two reactions. Parameters for the polymerization kinetics model are reported based on infrared spectrophotometry. Parameters describing the gas generating reaction are reported based on measurements of volume, temperature and pressure evolution with time. A foam rheology model is proposed and parameters determined through steady-shear and oscillatory tests. Heat of reaction and heat capacity are determined through differential scanning calorimetry. Thermal conductivity of the foam as a function of density is measured using a transient method based on the theory of the transient plane source technique. Finally, density variations of the resulting solid foam in several simple geometries are directly measured by sectioning and sampling mass, as well as through x-ray computed tomography. These density measurements will be useful for model validation once the complete model is implemented in an engineering code.
ModelPlex: Verified Runtime Validation of Verified Cyber-Physical System Models
Platzer, AndrÃ©
dynamics. In CPS, models are essential; but any model we could possibly build necessarily deviates from. In CPS, models are essential; but a cyber- physical systems (CPS) safe. Formal methods make strong guarantees about the system behavior
Numerical upscaling for the eddy-current model with stochastic magnetic materials
Eberhard, Jens P. [Computer Simulation Technology, Bad Nauheimer Strasse, 19, D-64289 Darmstadt (Germany)], E-mail: jens.eberhard@cst.com; Popovic, Dan [Simulation in Technology, University of Heidelberg, Im Neuenheimer Feld 368, D-69120 Heidelberg (Germany)], E-mail: dan.popovic@stud.uni-heidelberg.de; Wittum, Gabriel [Simulation in Technology, University of Heidelberg, Im Neuenheimer Feld 368, D-69120 Heidelberg (Germany)], E-mail: wittum@uni-hd.de
2008-04-01T23:59:59.000Z
This paper deals with the upscaling of the time-harmonic Maxwell equations for heterogeneous media. We analyze the eddy-current approximation of Maxwell's equations to describe the electric field for heterogeneous, isotropic magnetic materials. The magnetic permeability of the materials is assumed to have random heterogeneities described by a Gaussian random field. We apply the so-called Coarse Graining method to develop a numerical upscaling of the eddy-current model. The upscaling uses filtering and averaging procedures in Fourier space which results in a formulation of the eddy-current model on coarser resolution scales where the influence of sub-scale fluctuations is modeled by effective scale- and space-dependent reluctivity tensors. The effective reluctivity tensors can be obtained by solving local partial differential equations which contain a Laplacian as well as a curl-curl operator. We present a computational method how the equation of the combined operators can be discretized and solved numerically using an extended variational formulation compared to standard discretizations. We compare the results of the numerical upscaling of the eddy-current model with theoretical results of Eberhard [J.P. Eberhard, Upscaling for the time-harmonic Maxwell equations with heterogeneous magnetic materials, Physical Review E 72 (3), (2005)] and obtain a very good agreement.
LaCava, W.; Xing, Y.; Guo, Y.; Moan, T.
2012-04-01T23:59:59.000Z
The Gearbox Reliability Collaborative (GRC) has conducted extensive field and dynamometer test campaigns on two heavily instrumented wind turbine gearboxes. In this paper, data from the planetary stage is used to evaluate the accuracy and computation time of numerical models of the gearbox. First, planet-bearing load and motion data is analyzed to characterize planetary stage behavior in different environments and to derive requirements for gearbox models and life calculations. Second, a set of models are constructed that represent different levels of fidelity. Simulations of the test conditions are compared to the test data and the computational cost of the models are compared. The test data suggests that the planet-bearing life calculations should be made separately for each bearing on a row due to unequal load distribution. It also shows that tilting of the gear axes is related to planet load share. The modeling study concluded that fully flexible models were needed to predict planet-bearing loading in some cases, although less complex models were able to achieve good correlation in the field-loading case. Significant differences in planet load share were found in simulation and were dependent on the scope of the model and the bearing stiffness model used.
Prickett, T.A.
1980-04-01T23:59:59.000Z
Specifications are given which are necessary to develop a three-dimensional numerical model capable of simulating regional mass transport of radionuclides from a deep waste repository. The model to be developed will include all of the significant mass transport processes including flow, chemical, and thermal advection, mechanical dispersion, molecular diffusion, ion exchange reactions, and radioactive decay. The model specifications also include that density and viscosity fluid properties be functions of pressure, temperature, and concentration and take into account fluid and geologic heterogenieties by allowing possible assignment of individual values to every block of the model. The model specifications furthermore include the repository shape, input/output information, boundary conditions, and the need for documentation and a user's manual. Model code validation can be accomplished with the included known analytical or laboratory solutions. It is recommended that an existing finite-difference model (developed by INTERCOMP and INTERA, Inc.) be used as a starting point either as an acceptable basic code for modification or as a pattern for the development of a completely different numerical scheme. A ten-step plan is given to outline the general procedure for development of the code.
Validation of the Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps toValidatingCloudPoisson Stochastic Radiative
Validation of the RRTM Shortwave Radiation Model and Comparison to GCM Shortwave Models
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps toValidatingCloudPoisson Stochastic
Numerical Modeling of Non-adiabatic Heat-Recirculating Combustors C. H. Kuo and P. D. Ronney
1 Numerical Modeling of Non-adiabatic Heat-Recirculating Combustors C. H. Kuo and P. D. Ronney@usc.edu Colloquium topic area: 12. New Technology Concepts Keywords: Micro-combustion, Heat-recirculating combustors, Extinction limits Shortened running title: Numerical Modeling of Heat-Recirculating Combustors Word count
ModelPlex: Verified Runtime Validation of Verified Cyber-Physical System Models
-physical systems (CPS) safe. Formal methods make strong guarantees about the system behavior if accurate models of the sys- tem can be obtained, including models of the controller and of the physical dynamics. In CPS, models are essential; but any model we could possibly build necessarily deviates from the real world
Zhi, Yuanzhe
2013-07-11T23:59:59.000Z
model experimental results of solid dock are also compared with the numerical simulation. These comparisons indicate that the motion characteristics of the model container ship represent similar trends for both rotations and translations...
Jonathan Blackman; Scott E. Field; Chad R. Galley; Bela Szilagyi; Mark A. Scheel; Manuel Tiglio; Daniel A. Hemberger
2015-02-26T23:59:59.000Z
Simulating a binary black hole coalescence by solving Einstein's equations is computationally expensive, requiring days to months of supercomputing time. In this paper, we construct an accurate and fast-to-evaluate surrogate model for numerical relativity (NR) waveforms from non-spinning binary black hole coalescences with mass ratios from $1$ to $10$ and durations corresponding to about $15$ orbits before merger. Our surrogate, which is built using reduced order modeling techniques, is distinct from traditional modeling efforts. We find that the full multi-mode surrogate model agrees with waveforms generated by NR to within the numerical error of the NR code. In particular, we show that our modeling strategy produces surrogates which can correctly predict NR waveforms that were {\\em not} used for the surrogate's training. For all practical purposes, then, the surrogate waveform model is equivalent to the high-accuracy, large-scale simulation waveform but can be evaluated in a millisecond to a second depending on the number of output modes and the sampling rate. Our model includes all spherical-harmonic ${}_{-2}Y_{\\ell m}$ waveform modes that can be resolved by the NR code up to $\\ell=8$, including modes that are typically difficult to model with other approaches. We assess the model's uncertainty, which could be useful in parameter estimation studies seeking to incorporate model error. We anticipate NR surrogate models to be useful for rapid NR waveform generation in multiple-query applications like parameter estimation, template bank construction, and testing the fidelity of other waveform models.
Geant4 Model Validation of Compton Suppressed System for Process monitoring of Spent Fuel
Bender, Sarah; Unlu, Kenan; Orton, Christopher R.; Schwantes, Jon M.
2013-05-01T23:59:59.000Z
Nuclear material accountancy is of continuous concern for the regulatory, safeguards, and verification communities. In particular, spent nuclear fuel reprocessing facilities pose one of the most difficult accountancy challenges: monitoring highly radioactive, fluid sample streams in near real-time. The Multi-Isotope Process monitor will allow for near-real-time indication of process alterations using passive gamma-ray detection coupled with multivariate analysis techniques to guard against potential material diversion or to enhance domestic process monitoring. The Compton continuum from the dominant 661.7 keV 137Cs fission product peak obscures lower energy lines which could be used for spectral and multivariate analysis. Compton suppression may be able to mitigate the challenges posed by the high continuum caused by scattering. A Monte Carlo simulation using the Geant4 toolkit is being developed to predict the expected suppressed spectrum from spent fuel samples to estimate the reduction in the Compton continuum. Despite the lack of timing information between decay events in the particle management of Geant4, encouraging results were recorded utilizing only the information within individual decays without accounting for accidental coincidences. The model has been validated with single and cascade decay emitters in two steps: as an unsuppressed system and with suppression activated. Results of the Geant4 model validation will be presented.
Numerical-Model Investigation of the Hydrothermal Regime of a Straight-Through Shallow Cooling Pond
Sokolov, A. S. [JSC 'VNIIG im. B. E. Vedeneeva' (Russian Federation)] [JSC 'VNIIG im. B. E. Vedeneeva' (Russian Federation)
2013-11-15T23:59:59.000Z
A mathematic model based on solution of hydrodynamics and heat-transfer equations by the finite-element method is constructed to predict the hydrothermal regime of a straight-through shallow cooling pond, which provides cooling circulating water to a repository of spent nuclear fuel. Numerical experiments made it possible to evaluate the influence exerted by wind conditions and flow rate of water in the river on the temperature of the circulating water.
An investigation of analytical and numerical sucker rod pumping mathematical models
Schafer, Donald Joseph
1987-01-01T23:59:59.000Z
of MASTER OF SCIENCE May 1987 Major Subject: Petroleum Engineering AN INVESTIGATION OF ANALYTICAL AND NUMERICAL SUCKER ROD PUMPING MATHEMATICAL MODELS A Thesis by DONALD JOSEPH SCHAFER Approved as to style and content by: 7d JW. J ni (Chai... to Sucker Rod Pumping Research, Inc. , developed a method for computing downhole forces and displacements using an analog computer simulation. The procedure that results from this work, commonly called the API method, considers the total sucker rod...
Validated Models for Radiation Response and Signal Generation in Scintillators: Final Report
Kerisit, Sebastien N.; Gao, Fei; Xie, YuLong; Campbell, Luke W.; Van Ginhoven, Renee M.; Wang, Zhiguo; Prange, Micah P.; Wu, Dangxin
2014-12-01T23:59:59.000Z
This Final Report presents work carried out at Pacific Northwest National Laboratory (PNNL) under the project entitled “Validated Models for Radiation Response and Signal Generation in Scintillators” (Project number: PL10-Scin-theor-PD2Jf) and led by Drs. Fei Gao and Sebastien N. Kerisit. This project was divided into four tasks: 1) Electronic response functions (ab initio data model) 2) Electron-hole yield, variance, and spatial distribution 3) Ab initio calculations of information carrier properties 4) Transport of electron-hole pairs and scintillation efficiency Detailed information on the results obtained in each of the four tasks is provided in this Final Report. Furthermore, published peer-reviewed articles based on the work carried under this project are included in Appendix. This work was supported by the National Nuclear Security Administration, Office of Nuclear Nonproliferation Research and Development (DNN R&D/NA-22), of the U.S. Department of Energy (DOE).
Hughes, Patrick [ORNL; Im, Piljae [ORNL
2012-01-01T23:59:59.000Z
Geothermal heat pumps, sometimes called ground-source heat pumps (GSHPs), have been proven capable of significantly reducing energy use and peak demand in buildings. Conventional equipment for controlling the temperature and humidity of a building, or supplying hot water and fresh outdoor air, must exchange energy (or heat) with the building's outdoor environment. Equipment using the ground as a heat source and heat sink consumes less non-renewable energy (electricity and fossil fuels) because the earth is cooler than outdoor air in summer and warmer in winter. The most important barrier to rapid growth of the GSHP industry is high first cost of GSHP systems to consumers. The most common GSHP system utilizes a closed-loop ground heat exchanger. This type of GSHP system can be used almost anywhere. There is reason to believe that reducing the cost of closed-loop systems is the strategy that would achieve the greatest energy savings with GSHP technology. The cost premium of closed-loop GSHP systems over conventional space conditioning and water heating systems is primarily associated with drilling boreholes or excavating trenches, installing vertical or horizontal ground heat exchangers, and backfilling the excavations. This project investigates reducing the cost of horizontal closed-loop ground heat exchangers by installing them in the construction excavations, augmented when necessary with additional trenches. This approach applies only to new construction of residential and light commercial buildings or additions to such buildings. In the business-as-usual scenario, construction excavations are not used for the horizontal ground heat exchanger (HGHX); instead the HGHX is installed entirely in trenches dug specifically for that purpose. The potential cost savings comes from using the construction excavations for the installation of ground heat exchangers, thereby minimizing the need and expense of digging additional trenches. The term foundation heat exchanger (FHX) has been coined to refer exclusively to ground heat exchangers installed in the overcut around the basement walls. The primary technical challenge undertaken by this project was the development and validation of energy performance models and design tools for FHX. In terms of performance modeling and design, ground heat exchangers in other construction excavations (e.g., utility trenches) are no different from conventional HGHX, and models and design tools for HGHX already exist. This project successfully developed and validated energy performance models and design tools so that FHX or hybrid FHX/HGHX systems can be engineered with confidence, enabling this technology to be applied in residential and light commercial buildings. The validated energy performance model also addresses and solves another problem, the longstanding inadequacy in the way ground-building thermal interaction is represented in building energy models, whether or not there is a ground heat exchanger nearby. Two side-by-side, three-level, unoccupied research houses with walkout basements, identical 3,700 ft{sup 2} floor plans, and hybrid FHX/HGHX systems were constructed to provide validation data sets for the energy performance model and design tool. The envelopes of both houses are very energy efficient and airtight, and the HERS ratings of the homes are 44 and 45 respectively. Both houses are mechanically ventilated with energy recovery ventilators, with space conditioning provided by water-to-air heat pumps with 2 ton nominal capacities. Separate water-to-water heat pumps with 1.5 ton nominal capacities were used for water heating. In these unoccupied research houses, human impact on energy use (hot water draw, etc.) is simulated to match the national average. At House 1 the hybrid FHX/HGHX system was installed in 300 linear feet of excavation, and 60% of that was construction excavation (needed to construct the home). At House 2 the hybrid FHX/HGHX system was installed in 360 feet of excavation, 50% of which was construction excavation. There are six pipes in all excavations (three par
Numerical modeling of hydraulic fracture problem in permeable medium using cohesive zone model
Paris-Sud XI, Université de
or radioactive waste [30], geothermal Corresponding author Email address: benoit.carrier@enpc.fr (Benoit Carrier processes. During the last sixty years, numerous papers [3, 7, 14, 21, 35, 34, 41, 25, 27, 22, 38, 36, 1. In the recent years, a scaling and asymptotic framework was built to determine the influence of the physical
Thermo--inertial bouncing of a relativistic collapsing sphere: A numerical model
L. Herrera; A. Di Prisco; W. Barreto
2005-12-05T23:59:59.000Z
We present a numerical model of a collapsing radiating sphere, whose boundary surface undergoes bouncing due to a decreasing of its inertial mass density (and, as expected from the equivalence principle, also of the ``gravitational'' force term) produced by the ``inertial'' term of the transport equation. This model exhibits for the first time the consequences of such an effect, and shows that under physically reasonable conditions this decreasing of the gravitational term in the dynamic equation may be large enough as to revert the collapse and produce a bouncing of the boundary surface of the sphere.
Moist processes and the quasi-hydrostatic approximation in a mesoscale numerical model
Kennedy, Charles Joseph
1987-01-01T23:59:59.000Z
of Committee) James P. McGuirk (Member) J'ohn M. Klinck (Member) James R. Sco ns (Head of Department) December 1987 ABSTRACT Moist Processes and the Ouasi-Hydrostatic Approximation in a Mesoscale Numerical Model. (December 1987) Charles Joseph...HV)ds' ? gHp s + gHps a dg 1 gt = (gt), s 1 1 (19) the pressure tendency at the model top equation: g f V ~ (pHV)ds' ? VS Vp Q ( el 1 + 0 Yp CpT ? V (H0) ds' )' ? ) (20) Richardson's equation for vertical motion: s f , , f Id d'D &DDVdd ' ? 0 D, 0...
Probe measurements and numerical model predictions of evolving size distributions in premixed flames
De Filippo, A.; Sgro, L.A.; Lanzuolo, G.; D'Alessio, A. [Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli (Italy)
2009-09-15T23:59:59.000Z
Particle size distributions (PSDs), measured with a dilution probe and a Differential Mobility Analyzer (DMA), and numerical predictions of these PSDs, based on a model that includes only coagulation or alternatively inception and coagulation, are compared to investigate particle growth processes and possible sampling artifacts in the post-flame region of a C/O = 0.65 premixed laminar ethylene-air flame. Inputs to the numerical model are the PSD measured early in the flame (the initial condition for the aerosol population) and the temperature profile measured along the flame's axial centerline. The measured PSDs are initially unimodal, with a modal mobility diameter of 2.2 nm, and become bimodal later in the post-flame region. The smaller mode is best predicted with a size-dependent coagulation model, which allows some fraction of the smallest particles to escape collisions without resulting in coalescence or coagulation through the size-dependent coagulation efficiency ({gamma}{sub SD}). Instead, when {gamma} = 1 and the coagulation rate is equal to the collision rate for all particles regardless of their size, the coagulation model significantly under predicts the number concentration of both modes and over predicts the size of the largest particles in the distribution compared to the measured size distributions at various heights above the burner. The coagulation ({gamma}{sub SD}) model alone is unable to reproduce well the larger particle mode (mode II). Combining persistent nucleation with size-dependent coagulation brings the predicted PSDs to within experimental error of the measurements, which seems to suggest that surface growth processes are relatively insignificant in these flames. Shifting measured PSDs a few mm closer to the burner surface, generally adopted to correct for probe perturbations, does not produce a better matching between the experimental and the numerical results. (author)
Black liquor combustion validated recovery boiler modeling, five-year report
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1996-08-01T23:59:59.000Z
The objective of this project was to develop a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The project originated in October 1990 and was scheduled to run for four years. At that time, there was considerable emphasis on developing accurate predictions of the physical carryover of macroscopic particles of partially burnt black liquor and smelt droplets out of the furnace, since this was seen as the main cause of boiler plugging. This placed a major emphasis on gas flow patterns within the furnace and on the mass loss rates and swelling and shrinking rates of burning black liquor drops. As work proceeded on developing the recovery boiler furnace model, it became apparent that some recovery boilers encounter serious plugging problems even when physical carryover was minimal. After the original four-year period was completed, the project was extended to address this issue. The objective of the extended project was to improve the utility of the models by including the black liquor chemistry relevant to air emissions predictions and aerosol formation, and by developing the knowledge base and computational tools to relate furnace model outputs to fouling and plugging of the convective sections of the boilers. The work done to date includes CFD model development and validation, acquisition of information on black liquor combustion fundamentals and development of improved burning models, char bed model development, and model application and simplification.
Hassan, Yassin; Corradini, Michael; Tokuhiro, Akira; Wei, Thomas Y.C.
2014-07-14T23:59:59.000Z
The Reactor Cavity Cooling Systems (RCCS) is a passive safety system that will be incorporated in the VTHR design. The system was designed to remove the heat from the reactor cavity and maintain the temperature of structures and concrete walls under desired limits during normal operation (steady-state) and accident scenarios. A small scale (1:23) water-cooled experimental facility was scaled, designed, and constructed in order to study the complex thermohydraulic phenomena taking place in the RCCS during stead-state and transient conditions. The facility represents a portion of the reactor vessel with nine stainless steel coolant risers and utilizes water as coolant. The facility was equipped with instrumentation to measure temperatures and flow rates and a general verification was completed during the shakedown. A model of the experimental facility was prepared using RELAP5-3D and simulations were performed to validate the scaling procedure. The experimental data produced during the stead-state run were compared with the simulation results obtained using RELAP5-3D. The overall behavior of the facility met the expectations. The facility capabilities were confirmed to be very promising in performing additional experimental tests, including flow visualization, and produce data for code validation.
Ahmed Hassan
2004-09-01T23:59:59.000Z
The groundwater flow and radionuclide transport model characterizing the Shoal underground nuclear test has been accepted by the State of Nevada Division of Environmental Protection. According to the Federal Facility Agreement and Consent Order (FFACO) between DOE and the State of Nevada, the next steps in the closure process for the site are then model validation (or postaudit), the proof-of-concept, and the long-term monitoring stage. This report addresses the development of the validation strategy for the Shoal model, needed for preparing the subsurface Corrective Action Decision Document-Corrective Action Plan and the development of the proof-of-concept tools needed during the five-year monitoring/validation period. The approach builds on a previous model, but is adapted and modified to the site-specific conditions and challenges of the Shoal site.
Bayes Factor of Model Selection Validates FLMP Dominic W. Massaro, Michael M. Cohen,
Cohen, Michael M.
, using Newton's law of universal gravitation as an analogy, we argue that it might not be valid to expect
Broeer, Torsten; Fuller, Jason C.; Tuffner, Francis K.; Chassin, David P.; Djilali, Ned
2014-01-31T23:59:59.000Z
Electricity generation from wind power and other renewable energy sources is increasing, and their variability introduces new challenges to the power system. The emergence of smart grid technologies in recent years has seen a paradigm shift in redefining the electrical system of the future, in which controlled response of the demand side is used to balance fluctuations and intermittencies from the generation side. This paper presents a modeling framework for an integrated electricity system where loads become an additional resource. The agent-based model represents a smart grid power system integrating generators, transmission, distribution, loads and market. The model incorporates generator and load controllers, allowing suppliers and demanders to bid into a Real-Time Pricing (RTP) electricity market. The modeling framework is applied to represent a physical demonstration project conducted on the Olympic Peninsula, Washington, USA, and validation simulations are performed using actual dynamic data. Wind power is then introduced into the power generation mix illustrating the potential of demand response to mitigate the impact of wind power variability, primarily through thermostatically controlled loads. The results also indicate that effective implementation of Demand Response (DR) to assist integration of variable renewable energy resources requires a diversity of loads to ensure functionality of the overall system.
Validation of Multiple Tools for Flat Plate Photovoltaic Modeling Against Measured Data
Freeman, J.; Whitmore, J.; Blair, N.; Dobos, A. P.
2014-08-01T23:59:59.000Z
This report expands upon a previous work by the same authors, published in the 40th IEEE Photovoltaic Specialists conference. In this validation study, comprehensive analysis is performed on nine photovoltaic systems for which NREL could obtain detailed performance data and specifications, including three utility-scale systems and six commercial scale systems. Multiple photovoltaic performance modeling tools were used to model these nine systems, and the error of each tool was analyzed compared to quality-controlled measured performance data. This study shows that, excluding identified outliers, all tools achieve annual errors within +/-8% and hourly root mean squared errors less than 7% for all systems. It is further shown using SAM that module model and irradiance input choices can change the annual error with respect to measured data by as much as 6.6% for these nine systems, although all combinations examined still fall within an annual error range of +/-8.5%. Additionally, a seasonal variation in monthly error is shown for all tools. Finally, the effects of irradiance data uncertainty and the use of default loss assumptions on annual error are explored, and two approaches to reduce the error inherent in photovoltaic modeling are proposed.
Tesfatsion, Leigh
Validation of an Agent-based Model of Deregulated Electric Power Markets Charles M. Macal model of the electric power market designed to investigate market restructuring and deregulation, deregulated electric power markets Acknowledgments: The authors would like to acknowledge the other members
W. Schmidt; J. C. Niemeyer; W. Hillebrandt
2006-01-23T23:59:59.000Z
We present a one-equation subgrid scale model that evolves the turbulence energy corresponding to unresolved velocity fluctuations in large eddy simulations. The model is derived in the context of the Germano consistent decomposition of the hydrodynamical equations. The eddy-viscosity closure for the rate of energy transfer from resolved toward subgrid scales is localised by means of a dynamical procedure for the computation of the closure parameter. Therefore, the subgrid scale model applies to arbitrary flow geometry and evolution. For the treatment of microscopic viscous dissipation a semi-statistical approach is used, and the gradient-diffusion hypothesis is adopted for turbulent transport. A priori tests of the localised eddy-viscosity closure and the gradient-diffusion closure are made by analysing data from direct numerical simulations. As an a posteriori testing case, the large eddy simulation of thermonuclear combustion in forced isotropic turbulence is discussed. We intend the formulation of the subgrid scale model in this paper as a basis for more advanced applications in numerical simulations of complex astrophysical phenomena involving turbulence.
Thermodynamic modeling and experimental validation of the Fe-Al-Ni-Cr-Mo alloy system
Teng, Zhenke [ORNL; Zhang, F [CompuTherm LLC, Madison, WI; Miller, Michael K [ORNL; Liu, Chain T [Hong Kong Polytechnic University; Huang, Shenyan [ORNL; Chou, Y.T. [Multi-Phase Services Inc., Knoxville; Tien, R [Multi-Phase Services Inc., Knoxville; Chang, Y A [ORNL; Liaw, Peter K [University of Tennessee, Knoxville (UTK)
2012-01-01T23:59:59.000Z
NiAl-type precipitate-strengthened ferritic steels have been known as potential materials for the steam turbine applications. In this study, thermodynamic descriptions of the B2-NiAl type nano-scaled precipitates and body-centered-cubic (BCC) Fe matrix phase for four alloys based on the Fe-Al-Ni-Cr-Mo system were developed as a function of the alloy composition at the aging temperature. The calculated phase structure, composition, and volume fraction were validated by the experimental investigations using synchrotron X-ray diffraction and atom probe tomography. With the ability to accurately predict the key microstructural features related to the mechanical properties in a given alloy system, the established thermodynamic model in the current study may significantly accelerate the alloy design process of the NiAl-strengthened ferritic steels.
Polasek, J. C
1981-01-01T23:59:59.000Z
COLLECTION OF A DATA BASE FOR THE CONSTRUCTION AND VALIDATION OF ROADWAY AIR POLLUTION DISPERSION MODELS A Thesis by JOHN C. POLASEK Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements... I. H. 610 0 ~o ~ ~o FIGURE 1 OVERHEAD VIEW ? Houston, Loop 610 Ij2 =VAI 5M, HA I 5M TMI 5M, WVI 5M, RH I 5M 12f c VA I OM, HA IOM, TMP IOM, WV 1 0 M 8O VA 2OM, HA 20M, TMP 2OM, WV 20 M 4D= TMP 30 M, RH 3OM OT = VA 4 0 M, HA 40 M, W V 40 M...
Irminger, Philip [ORNL; Starke, Michael R [ORNL; Dimitrovski, Aleksandar D [ORNL; Young II, Marcus Aaron [ORNL; Rizy, D Tom [ORNL; Stovall, John P [ORNL; Overholt, Philip N [U.S. Department of Energy, Office of Electricity Delivery and Energy Reliability (OE)
2014-01-01T23:59:59.000Z
Power system equipment manufacturers and researchers continue to experiment with novel overhead electric conductor designs that support better conductor performance and address congestion issues. To address the technology gap in testing these novel designs, Oak Ridge National Laboratory constructed the Powerline Conductor Accelerated Testing (PCAT) facility to evaluate the performance of novel overhead conductors in an accelerated fashion in a field environment. Additionally, PCAT has the capability to test advanced sensors and measurement methods for accessing overhead conductor performance and condition. Equipped with extensive measurement and monitoring devices, PCAT provides a platform to improve/validate conductor computer models and assess the performance of novel conductors. The PCAT facility and its testing capabilities are described in this paper.
Sobolik, S.R.; Miller, J.D.
1996-09-01T23:59:59.000Z
The U.S. Department of Energy`s (DOE) Yucca Mountain Site Characterization Project (YMP) is studying Yucca Mountain in southwestern Nevada as a potential site for a high-level nuclear waste repository. Site characterization will be facilitated by the construction of an Exploratory Studies Facility (ESF). The ESF and potential repository will be excavated from both nonwelded and welded ashflow tuff with varying rock quality (degree of welding, rock mass strength, etc.) and fault and fracture characteristics. Design concerns for the construction of these facilities include the integrity of the structure during underground testing operations and, if it occurs, the emplacement and storage of high-level nuclear waste which could increase the local temperatures in the underground rock mass to as high as 300{degrees}C. Because of the associated issues regarding personnel and long-term environmental safety, sophisticated jointed rock mass models will be required to provide a high degree of confidence for decisions regarding the design, site characterization, and licensing of such facilities. The objective of the work documented in this report is to perform code validation calculations for three rock-mass computer models. The three rock-mass computer models used for this report are the discrete element code UDEC, Version 1.82; and the finite element continuum joint models JAC2D Version 5.10 and JAS3D Version 1.1. The rock mass behavior predicted by the models are compared to the results of laboratory experiments on layered polycarbonate (Lexan) and granite plate experiments. These experiments examine the rock mass behavior of well-defined jointed rock structures or models of jointed structures under uniaxial and biaxial loading. The laboratory environment allows control over the boundary conditions, material properties, and quality and quantity of the data obtained.
Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models
Weitzel, E.; Hoeschele, M.
2014-09-01T23:59:59.000Z
A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. A full distribution system developed in TRNSYS has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. This study builds upon previous analysis modelling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall 124 different TRNSYS models were simulated. Of the configurations evaluated, distribution losses account for 13-29% of the total water heating energy use and water use efficiency ranges from 11-22%. The base case, an uninsulated trunk and branch system sees the most improvement in energy consumption by insulating and locating the water heater central to all fixtures. Demand recirculation systems are not projected to provide significant energy savings and in some cases increase energy consumption. Water use is most efficient with demand recirculation systems, followed by the insulated trunk and branch system with a central water heater. Compact plumbing practices and insulation have the most impact on energy consumption (2-6% for insulation and 3-4% per 10 gallons of enclosed volume reduced). The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.
Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM
Robinson, Martin; Ramaioli, Marco
2013-01-01T23:59:59.000Z
We present a meshless simulation method for multiphase fluid-particle flows coupling Smoothed Particle Hydrodynamics (SPH) and the Discrete Element Method (DEM). Rather than fully resolving the interstitial fluid, which is often infeasible, the unresolved fluid model is based on the locally averaged Navier Stokes equations, which are coupled with a DEM model for the solid phase. In contrast to similar mesh-based Discrete Particle Methods (DPMs), this is a purely particle-based method and enjoys the flexibility that comes from the lack of a prescribed mesh. It is suitable for problems such as free surface flow or flow around complex, moving and/or intermeshed geometries. It can be used for both one and two-way coupling and is applicable to both dilute and dense particle flows. A comprehensive validation procedure for fluid-particle simulations is presented and applied to the SPH-DEM method, using simulations of single and multiple particle sedimentation in a 3D fluid column and comparison with analytical model...
Schmidt, W; Niemeyer, J C
2006-01-01T23:59:59.000Z
We present a one-equation subgrid scale model that evolves the turbulence energy corresponding to unresolved velocity fluctuations in large eddy simulations. The model is derived in the context of the Germano consistent decomposition of the hydrodynamical equations. The eddy-viscosity closure for the rate of energy transfer from resolved toward subgrid scales is localised by means of a dynamical procedure for the computation of the closure parameter. Therefore, the subgrid scale model applies to arbitrary flow geometry and evolution. For the treatment of microscopic viscous dissipation a semi-statistical approach is used, and the gradient-diffusion hypothesis is adopted for turbulent transport. A priori tests of the localised eddy-viscosity closure and the gradient-diffusion closure are made by analysing data from direct numerical simulations. As an a posteriori testing case, the large eddy simulation of thermonuclear combustion in forced isotropic turbulence is discussed. We intend the formulation of the sub...
The LIGO Scientific Collaboration; the Virgo Collaboration; the NINJA-2 Collaboration; :; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; B. Behnke; M. Bejger; M. G. Beker; C. Belczynski; A. S. Bell; C. Bell; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; M. Blom; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavaglià; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley; W. Kells; A. Khalaidovski
2014-01-05T23:59:59.000Z
The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave astrophysics communities. The purpose of NINJA is to study the ability to detect gravitational waves emitted from merging binary black holes and recover their parameters with next-generation gravitational-wave observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete binary black hole hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a "blind injection challenge" similar to that conducted in recent LIGO and Virgo science runs, we added 7 hybrid waveforms to two months of data recolored to predictions of Advanced LIGO and Advanced Virgo sensitivity curves during their first observing runs. The resulting data was analyzed by gravitational-wave detection algorithms and 6 of the waveforms were recovered with false alarm rates smaller than 1 in a thousand years. Parameter estimation algorithms were run on each of these waveforms to explore the ability to constrain the masses, component angular momenta and sky position of these waveforms. We also perform a large-scale monte-carlo study to assess the ability to recover each of the 60 hybrid waveforms with early Advanced LIGO and Advanced Virgo sensitivity curves. Our results predict that early Advanced LIGO and Advanced Virgo will have a volume-weighted average sensitive distance of 300Mpc (1Gpc) for $10M_{\\odot}+10M_{\\odot}$ ($50M_{\\odot}+50M_{\\odot}$) binary black hole coalescences. We demonstrate that neglecting the component angular momenta in the waveform models used in matched-filtering will result in a reduction in sensitivity for systems with large component angular momenta. [Abstract abridged for ArXiv, full version in PDF
Monitoring and Numerical Modeling of Shallow CO{sub 2} Injection, Greene County, Missouri
Rovey, Charles; Gouzie, Douglas; Biagioni, Richard
2013-09-30T23:59:59.000Z
The project titled Monitoring and Numerical Modeling of Shallow CO{sub 2} Injection, Greene County, Missouri provided training for three graduate students in areas related to carbon capture and storage. Numerical modeling of CO{sub 2} injection into the St. Francois aquifer at the Southwest Power Plant Site in Greene County, Missouri indicates that up to 4.1 x 10{sup 5} metric tons of CO{sub 2} per year could be injected for 30 years without exceeding a 3 MPa differential injection pressure. The injected CO{sub 2} would remain sequestered below the top of the overlying caprock (St. Francois confining unit) for more than 1000 years. Geochemical modeling indicates that portions of the injected CO{sub 2} will react rapidly with trace minerals in the aquifer to form various solid carbonate mineral phases. These minerals would store significant portions of injected CO{sub 2} over geologic time scales. Finally, a GIS data base on the pore-fluid chemistry of the overlying aquifer system in Missouri, the Ozark aquifer, was compiled from many sources. This data base could become useful in monitoring for leakage from future CO{sub 2} sequestration sites.
A phase screen model for simulating numerically the propagation of a laser beam in rain
Lukin, I P; Rychkov, D S; Falits, A V [Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk (Russian Federation); Lai, Kin S; Liu, Min R [DSO National Laboratories 20 (Singapore)
2009-09-30T23:59:59.000Z
The method based on the generalisation of the phase screen method for a continuous random medium is proposed for simulating numerically the propagation of laser radiation in a turbulent atmosphere with precipitation. In the phase screen model for a discrete component of a heterogeneous 'air-rain droplet' medium, the amplitude screen describing the scattering of an optical field by discrete particles of the medium is replaced by an equivalent phase screen with a spectrum of the correlation function of the effective dielectric constant fluctuations that is similar to the spectrum of a discrete scattering component - water droplets in air. The 'turbulent' phase screen is constructed on the basis of the Kolmogorov model, while the 'rain' screen model utiises the exponential distribution of the number of rain drops with respect to their radii as a function of the rain intensity. Theresults of the numerical simulation are compared with the known theoretical estimates for a large-scale discrete scattering medium. (propagation of laser radiation in matter)
Numerical modeling of mixed sediment resuspension, transport, and deposition during the March 1998 sediment resuspension of mixed (cohesive plus noncohesive) sediment is developed and applied to quantitatively simulate the March 1998 resuspension events in southern Lake Michigan. Some characteristics
Tice, Julie Anne Goodwin
1996-01-01T23:59:59.000Z
MODELING by JULIE ANNE GOODWiN TICE Submitted to the Office of Graduate Studies of Texas AkM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved to style and conte t by: Judith M. Col ' (Chair... Performance Using Structural Equation Modeling. (December 1996) Julie Anne Goodwm Tice, B. A. , Northwestern University Chair of Advisory Committee: Dr. Judith M. Collins This research used structural equation modeling to test the construct validity...
Choi, Yong-Joon; Ronnebro, Ewa; Rassat, Scot D.; Karkamkar, Abhijeet J.; Maupin, Gary D.; Holladay, Jamelyn D.; Simmons, Kevin L.; Brooks, Kriston P.
2014-02-24T23:59:59.000Z
Ammonia borane (AB), NH3BH3, is a promising material for chemical hydrogen storage with 19.6 wt% gravimetric hydrogen capacity of which 16.2 wt% hydrogen can be utilized below 200°C. We have investigated the kinetics of hydrogen release from AB and from an AB-methyl cellulose (AB/MC) composite at temperatures of 160-300°C using both experiments and modeling. The purpose of our study was to show safe hydrogen release without thermal runaway effects and to validate system model kinetics. AB/MC released hydrogen at ~20°C lower than neat AB and at a rate that is two times faster. Based on the experimental results, the kinetics equations were revised to better represent the growth and nucleation process during decomposition of AB. We explored two different reactor concepts; Auger and fixed bed. The current Auger reactor concept turned out to not be appropriate, however, we demonstrated safe self-propagation of the hydrogen release reaction of solid AB/MC in a fixed bed reactor.
Pan, Dongqing; Chien Jen, Tien [Department of Mechanical Engineering, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201 (United States); Li, Tao [School of Mechanical Engineering, Dalian University of Technology, Dalian 116024 (China); Yuan, Chris, E-mail: cyuan@uwm.edu [Department of Mechanical Engineering, University of Wisconsin-Milwaukee, 3200 North Cramer Street, Milwaukee, Wisconsin 53211 (United States)
2014-01-15T23:59:59.000Z
This paper characterizes the carrier gas flow in the atomic layer deposition (ALD) vacuum reactor by introducing Lattice Boltzmann Method (LBM) to the ALD simulation through a comparative study of two LBM models. Numerical models of gas flow are constructed and implemented in two-dimensional geometry based on lattice Bhatnagar–Gross–Krook (LBGK)-D2Q9 model and two-relaxation-time (TRT) model. Both incompressible and compressible scenarios are simulated and the two models are compared in the aspects of flow features, stability, and efficiency. Our simulation outcome reveals that, for our specific ALD vacuum reactor, TRT model generates better steady laminar flow features all over the domain with better stability and reliability than LBGK-D2Q9 model especially when considering the compressible effects of the gas flow. The LBM-TRT is verified indirectly by comparing the numerical result with conventional continuum-based computational fluid dynamics solvers, and it shows very good agreement with these conventional methods. The velocity field of carrier gas flow through ALD vacuum reactor was characterized by LBM-TRT model finally. The flow in ALD is in a laminar steady state with velocity concentrated at the corners and around the wafer. The effects of flow fields on precursor distributions, surface absorptions, and surface reactions are discussed in detail. Steady and evenly distributed velocity field contribute to higher precursor concentration near the wafer and relatively lower particle velocities help to achieve better surface adsorption and deposition. The ALD reactor geometry needs to be considered carefully if a steady and laminar flow field around the wafer and better surface deposition are desired.
Numeric-modeling sensitivity analysis of the performance of wind turbine arrays
Lissaman, P.B.S.; Gyatt, G.W.; Zalay, A.D.
1982-06-01T23:59:59.000Z
An evaluation of the numerical model created by Lissaman for predicting the performance of wind turbine arrays has been made. Model predictions of the wake parameters have been compared with both full-scale and wind tunnel measurements. Only limited, full-scale data were available, while wind tunnel studies showed difficulties in representing real meteorological conditions. Nevertheless, several modifications and additions have been made to the model using both theoretical and empirical techniques and the new model shows good correlation with experiment. The larger wake growth rate and shorter near wake length predicted by the new model lead to reduced interference effects on downstream turbines and hence greater array efficiencies. The array model has also been re-examined and now incorporates the ability to show the effects of real meteorological conditions such as variations in wind speed and unsteady winds. The resulting computer code has been run to show the sensitivity of array performance to meteorological, machine, and array parameters. Ambient turbulence and windwise spacing are shown to dominate, while hub height ratio is seen to be relatively unimportant. Finally, a detailed analysis of the Goodnoe Hills wind farm in Washington has been made to show how power output can be expected to vary with ambient turbulence, wind speed, and wind direction.
Full-Scale Numerical Modeling of Turbulent Processes in the Earth's Ionosphere
Eliasson, B. [Department of Physics, Umeaa University, SE-901 87 Umeaa (Sweden); Stenflo, L. [Department of Physics, Umeaa University, SE-901 87 Umeaa (Sweden); Department of Physics, Linkoeping University, SE-581 83 Linkoeping (Sweden); Shukla, P. K. [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)
2008-10-15T23:59:59.000Z
We present a full-scale simulation study of ionospheric turbulence by means of a generalized Zakharov model based on the separation of variables into high-frequency and slow time scales. The model includes realistic length scales of the ionospheric profile and of the electromagnetic and electrostatic fields, and uses ionospheric plasma parameters relevant for high-latitude radio facilities such as Eiscat and HAARP. A nested grid numerical method has been developed to resolve the different length-scales, while avoiding severe restrictions on the time step. The simulation demonstrates the parametric decay of the ordinary mode into Langmuir and ion-acoustic waves, followed by a Langmuir wave collapse and short-scale caviton formation, as observed in ionospheric heating experiments.
Numerical modeling of roll structures in mesoscale vortexes over the Black Sea
Iarova, D A
2014-01-01T23:59:59.000Z
This paper is a case study of horizontal atmospheric rolls that formed over the Black Sea on 16 August 2007. The rolls were discovered in WRF modeling results for a mesoscale cyclone that originated over the sea on 15 August 2007. The roll formation mechanisms, such as Rayleigh-Benard convective instability, dynamic instability, advection and stretching of vertical velocity field inhomogeneities, are considered. It is shown that indeed convective instability played an important role in the roll formation but dynamic instability did not occur. In order to distinguish other possible mechanisms of the roll formation numerical experiments were performed. In these experiments sea surface temperature in the initial conditions was decreased in order to prevent convective instability. Even though convective instability was suppressed roll-like structures still appeared in the modeling results, although their height and circulation velocity were smaller than in the control run. It was found that these structures were ...
Huang, Xun
19th. AIAA-CEAS Aeroacoutics Conference, May 28th 2013, Berlin Dynamic Modeling and Numerical was presented in this paper. By this control-oriented model, transient dynamic process of multi-physics coupling problem in a progressive wave tube could be approximately studied. The proposed model is verified
place. 2. The basic model can be varied to suit foragers that optimise either their rate of net energy uptake or their foraging ef®ciency. 3. The model requires speci®cation of the time and energy budgetsAn economic model of the limits to foraging range in central place foragers with numerical
A Bulk Tungsten Tile for JET: Derivation of Power-Handling Performance and Validation of the Thermal Model, in the MARION Facility
Valerio, Luis G., E-mail: luis.valerio@fda.hhs.gov [Science and Research Staff, Office of Pharmaceutical Science, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993–0002 (United States); Cross, Kevin P. [Leadscope, Inc., 1393 Dublin Road, Columbus, OH, 43215–1084 (United States)] [Leadscope, Inc., 1393 Dublin Road, Columbus, OH, 43215–1084 (United States)
2012-05-01T23:59:59.000Z
Control and minimization of human exposure to potential genotoxic impurities found in drug substances and products is an important part of preclinical safety assessments of new drug products. The FDA's 2008 draft guidance on genotoxic and carcinogenic impurities in drug substances and products allows use of computational quantitative structure–activity relationships (QSAR) to identify structural alerts for known and expected impurities present at levels below qualified thresholds. This study provides the information necessary to establish the practical use of a new in silico toxicology model for predicting Salmonella t. mutagenicity (Ames assay outcome) of drug impurities and other chemicals. We describe the model's chemical content and toxicity fingerprint in terms of compound space, molecular and structural toxicophores, and have rigorously tested its predictive power using both cross-validation and external validation experiments, as well as case studies. Consistent with desired regulatory use, the model performs with high sensitivity (81%) and high negative predictivity (81%) based on external validation with 2368 compounds foreign to the model and having known mutagenicity. A database of drug impurities was created from proprietary FDA submissions and the public literature which found significant overlap between the structural features of drug impurities and training set chemicals in the QSAR model. Overall, the model's predictive performance was found to be acceptable for screening drug impurities for Salmonella mutagenicity. -- Highlights: ? We characterize a new in silico model to predict mutagenicity of drug impurities. ? The model predicts Salmonella mutagenicity and will be useful for safety assessment. ? We examine toxicity fingerprints and toxicophores of this Ames assay model. ? We compare these attributes to those found in drug impurities known to FDA/CDER. ? We validate the model and find it has a desired predictive performance.
Paris-Sud XI, Université de
Central South Pacific thermocline water circulation from a high-resolution ocean model validated. Introduction [2] Most South Pacific Ocean studies have been focused on its western or eastern part, leaving 12 January 2009; accepted 28 January 2009; published 13 May 2009. [1] The oceanic circulation
Paik, Joongcheol [University of Minnesota; Sotiropoulos, Fotis [University of Minnesota; Sale, Michael J [ORNL
2005-06-01T23:59:59.000Z
A numerical method is developed for carrying out unsteady Reynolds-averaged Navier-Stokes (URANS) simulations and detached-eddy simulations (DESs) in complex 3D geometries. The method is applied to simulate incompressible swirling flow in a typical hydroturbine draft tube, which consists of a strongly curved 90 degree elbow and two piers. The governing equations are solved with a second-order-accurate, finite-volume, dual-time-stepping artificial compressibility approach for a Reynolds number of 1.1 million on a mesh with 1.8 million nodes. The geometrical complexities of the draft tube are handled using domain decomposition with overset (chimera) grids. Numerical simulations show that unsteady statistical turbulence models can capture very complex 3D flow phenomena dominated by geometry-induced, large-scale instabilities and unsteady coherent structures such as the onset of vortex breakdown and the formation of the unsteady rope vortex downstream of the turbine runner. Both URANS and DES appear to yield the general shape and magnitude of mean velocity profiles in reasonable agreement with measurements. Significant discrepancies among the DES and URANS predictions of the turbulence statistics are also observed in the straight downstream diffuser.
Cheng, C. L.; Gragg, M. J.; Perfect, E.; White, Mark D.; Lemiszki, P. J.; McKay, L. D.
2013-08-24T23:59:59.000Z
Numerical simulations are widely used in feasibility studies for geologic carbon sequestration. Accurate estimates of petrophysical parameters are needed as inputs for these simulations. However, relatively few experimental values are available for CO2-brine systems. Hence, a sensitivity analysis was performed using the STOMP numerical code for supercritical CO2 injected into a model confined deep saline aquifer. The intrinsic permeability, porosity, pore compressibility, and capillary pressure-saturation/relative permeability parameters (residual liquid saturation, residual gas saturation, and van Genuchten alpha and m values) were varied independently. Their influence on CO2 injection rates and costs were determined and the parameters were ranked based on normalized coefficients of variation. The simulations resulted in differences of up to tens of millions of dollars over the life of the project (i.e., the time taken to inject 10.8 million metric tons of CO2). The two most influential parameters were the intrinsic permeability and the van Genuchten m value. Two other parameters, the residual gas saturation and the residual liquid saturation, ranked above the porosity. These results highlight the need for accurate estimates of capillary pressure-saturation/relative permeability parameters for geologic carbon sequestration simulations in addition to measurements of porosity and intrinsic permeability.
Numerical Modeling of Thermal EOR: Comprehensive Coupling of an AMR-Based Model
Paris-Sud XI, Université de
Flow and Geomechanics N. Guy*, G. Enchéry and G. Renard IFP Energies nouvelles, 1-4 avenue de Bois of Thermal EOR: Comprehensive Coupling of an AMR-Based Model of Thermal Fluid Flow and Geomechanics when both thermal fluid flow and geomechanics are coupled in order to take into account variations
Khangaonkar, Tarang; Yang, Zhaoqing; Kim, Tae Yun; Roberts, Mindy
2011-07-20T23:59:59.000Z
Through extensive field data collection and analysis efforts conducted since the 1950s, researchers have established an understanding of the characteristic features of circulation in Puget Sound. The pattern ranges from the classic fjordal behavior in some basins, with shallow brackish outflow and compensating inflow immediately below, to the typical two-layer flow observed in many partially mixed estuaries with saline inflow at depth. An attempt at reproducing this behavior by fitting an analytical formulation to past data is presented, followed by the application of a three-dimensional circulation and transport numerical model. The analytical treatment helped identify key physical processes and parameters, but quickly reconfirmed that response is complex and would require site-specific parameterization to include effects of sills and interconnected basins. The numerical model of Puget Sound, developed using unstructured-grid finite volume method, allowed resolution of the sub-basin geometric features, including presence of major islands, and site-specific strong advective vertical mixing created by bathymetry and multiple sills. The model was calibrated using available recent short-term oceanographic time series data sets from different parts of the Puget Sound basin. The results are compared against (1) recent velocity and salinity data collected in Puget Sound from 2006 and (2) a composite data set from previously analyzed historical records, mostly from the 1970s. The results highlight the ability of the model to reproduce velocity and salinity profile characteristics, their variations among Puget Sound subbasins, and tidally averaged circulation. Sensitivity of residual circulation to variations in freshwater inflow and resulting salinity gradient in fjordal sub-basins of Puget Sound is examined.
Gauntt, Stephen Byron
2009-05-15T23:59:59.000Z
Prediction of bubble formation during filling of microchambers is often critical for determining the efficacy of microfluidic devices in various applications. In this study experimental validation is performed to verify the predictions from a...
Biomarker Discovery and Validation for Proteomics and Genomics: Modeling And Systematic Analysis
Atashpazgargari, Esmaeil
2014-08-27T23:59:59.000Z
relative to the complexity of the decision boundary. The results show that all the estimation methods lose accuracy as complexity increases. Validation of a set of selected biomarkers from a list of candidates is an important stage in the biomarker...
Gauntt, Stephen Byron
2009-05-15T23:59:59.000Z
Prediction of bubble formation during filling of microchambers is often critical for determining the efficacy of microfluidic devices in various applications. In this study experimental validation is performed to verify the predictions from a...
Boyer, Edmond
Introduction Flattening the Earth Continuation procedure Flat Earth Numerical simulations Continuation from a flat to a round Earth model in the coplanar orbit transfer problem M. Cerf1, T. Haberkorn, SADCO 2011, March 2nd M. Cerf, T. Haberkorn, E. Tr´elat Continuation from a flat to a round Earth model
Paris-Sud XI, Université de
1 Numerical modelling of hybrid arc/laser welding: a Level Set approach for weld bead formation.Bellet@mines-paristech.fr ABSTRACT The joining of high thickness steel sheets by means of hybrid Laser/GMAW welding processes of the workpiece borders. Two finite elements models are presented to illustrate: (i) A hybrid arc/laser welding
An efficient numerical model for incompressible two-phase flow in fractured media Hussein Hoteit a,1
Firoozabadi, Abbas
in fractured hydrocarbon reservoirs [16]. In this model, the matrixfracture mass transfer is describedAn efficient numerical model for incompressible two-phase flow in fractured media Hussein Hoteit a,1 , Abbas Firoozabadi a,b,* a Reservoir Engineering Research Institute, Palo Alto, CA, USA b Yale
Beaumont, Christopher
Numerical Modeling of Salt Tectonics on Passive Continental Margins: Preliminary Assessment Sciences The University of Leeds LS2 9JT Leeds United Kingdom Abstract Salt tectonics in passive model of frictional-plastic sedimentary overburden overlying a linear viscous salt layer. We present
Paris-Sud XI, Université de
Stochastic reduced-order model for an automotive vehicle in presence of numerous local elastic a high modal density in the low-frequency range, such as an automotive vehicle. This type of structure is applied on a complex computational model of an automotive vehicle. 1 INTRODUCTION This work is performed
Bharathan, D.; Parsons, B.K.; Althof, J.A.
1988-10-01T23:59:59.000Z
The objective of the reported work was to develop analytical methods for evaluating the design and performance of advanced high-performance heat exchangers for use in open-cycle thermal energy conversion (OC-OTEC) systems. This report describes the progress made on validating a one-dimensional, steady-state analytical computer of fresh water experiments. The condenser model represents the state of the art in direct-contact heat exchange for condensation for OC-OTEC applications. This is expected to provide a basis for optimizing OC-OTEC plant configurations. Using the model, we examined two condenser geometries, a cocurrent and a countercurrent configuration. This report provides detailed validation results for important condenser parameters for cocurrent and countercurrent flows. Based on the comparisons and uncertainty overlap between the experimental data and predictions, the model is shown to predict critical condenser performance parameters with an uncertainty acceptable for general engineering design and performance evaluations. 33 refs., 69 figs., 38 tabs.
active protection element. Second, if several relay models are in a multi-terminal scenario, the relay digital protective relay data analysis application (DPRDA). It is originally developed for validationAbstract--This paper presents the development of a novel digital relay model and its validation
Rodríguez Alvarado, Juan Fernando
2010-01-01T23:59:59.000Z
The need for innovation in the renewable energy sector is an ever-growing concern. With national-level disasters in the Gulf of Mexico, the necessity to begin the drive to develop effective and practical alternative energy ...
SU-E-T-50: Automatic Validation of Megavoltage Beams Modeled for Clinical Use in Radiation Therapy
Melchior, M [Terapia Radiante S.A., La Plata, Buenos Aires (Argentina); Salinas Aranda, F [Vidt Centro Medico, Ciudad Autonoma De Buenos Aires (Argentina); 21st Century Oncology, Ft. Myers, FL (United States); Sciutto, S [Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina); Dodat, D [Centro Medico Privado Dean Funes, La Plata, Buenos Aires (Argentina); Larragueta, N [Universidad Nacional de La Plata, La Plata, Buenos Aires (Argentina); Centro Medico Privado Dean Funes, La Plata, Buenos Aires (Argentina)
2014-06-01T23:59:59.000Z
Purpose: To automatically validate megavoltage beams modeled in XiO™ 4.50 (Elekta, Stockholm, Sweden) and Varian Eclipse™ Treatment Planning Systems (TPS) (Varian Associates, Palo Alto, CA, USA), reducing validation time before beam-on for clinical use. Methods: A software application that can automatically read and analyze DICOM RT Dose and W2CAD files was developed using MatLab integrated development environment.TPS calculated dose distributions, in DICOM RT Dose format, and dose values measured in different Varian Clinac beams, in W2CAD format, were compared. Experimental beam data used were those acquired for beam commissioning, collected on a water phantom with a 2D automatic beam scanning system.Two methods were chosen to evaluate dose distributions fitting: gamma analysis and point tests described in Appendix E of IAEA TECDOC-1583. Depth dose curves and beam profiles were evaluated for both open and wedged beams. Tolerance parameters chosen for gamma analysis are 3% and 3 mm dose and distance, respectively.Absolute dose was measured independently at points proposed in Appendix E of TECDOC-1583 to validate software results. Results: TPS calculated depth dose distributions agree with measured beam data under fixed precision values at all depths analyzed. Measured beam dose profiles match TPS calculated doses with high accuracy in both open and wedged beams. Depth and profile dose distributions fitting analysis show gamma values < 1. Relative errors at points proposed in Appendix E of TECDOC-1583 meet therein recommended tolerances.Independent absolute dose measurements at points proposed in Appendix E of TECDOC-1583 confirm software results. Conclusion: Automatic validation of megavoltage beams modeled for their use in the clinic was accomplished. The software tool developed proved efficient, giving users a convenient and reliable environment to decide whether to accept or not a beam model for clinical use. Validation time before beam-on for clinical use was reduced to a few hours.
Verification and Validation of RADTRAN 5.5.
Osborn, Douglas.; Weiner, Ruth F.; Mills, George Scott; Hamp, Steve C.
2005-02-01T23:59:59.000Z
This document contains a description of the verification and validation process used for the RADTRAN 5.5 code. The verification and validation process ensured the proper calculational models and mathematical and numerical methods were used in the RADTRAN 5.5 code for the determination of risk and consequence assessments. The differences between RADTRAN 5 and RADTRAN 5.5 are the addition of tables, an expanded isotope library, and the additional User-Defined meteorological option for accident dispersion. 3
Zuo, Wangda; Chen, Qingyan
2011-06-01T23:59:59.000Z
To design a healthy indoor environment, it is important to study airborne particle distribution indoors. As an intermediate model between multizone models and computational fluid dynamics (CFD), a fast fluid dynamics (FFD) model can be used to provide temporal and spatial information of particle dispersion in real time. This study evaluated the accuracy of the FFD for predicting transportation of particles with low Stokes number in a duct and in a room with mixed convection. The evaluation was to compare the numerical results calculated by the FFD with the corresponding experimental data and the results obtained by the CFD. The comparison showed that the FFD could capture major pattern of particle dispersion, which is missed in models with well-mixed assumptions. Although the FFD was less accurate than the CFD partially due to its simplification in numeric schemes, it was 53 times faster than the CFD.
Numerical-model developments for stimulation technologies in the Eastern Gas Shales Project
Barbour, T.G.; Maxwell, D.E.; Young, C.
1980-01-01T23:59:59.000Z
These efforts were directed towards the development of a numerical tensile failure model that could be used to make a parameter sensitivity study of the EGSP wellbore stimulation methods for gas recovery in Devonain shales, calculations were performed using the NTS Multi-Frac Mineback Experiments as the geometry, boundary conditions and material properties of the models. Several major accomplishments were achieved during this task. These include: development of a Crack and Void Strain (CAVS) tensile failure model for one-dimensional fracture analysis using the one-dimensional geometries available in SAI's STEALTH 1-D finite-difference code; modification of the original CAVS tensile failure criteria to improve its representation of multiple fracture development by introducing a logic that adjusts the material's tensile strength (both for crack initiation and crack propagation) according to the degree of cracking that has occurred; adding a submodel to CAVS to allow for cracking propping when a crack is reclosed and to require energy to be expanded during this process; adding a submodel to CAVS to allow for crack pressurization when a crack void strain is in communication with the fluid pressure of the borehole; and performing a parameter sensitivity analysis to determine the effect that the material properties of the rock has on crack development, to include the effects of yielding and compaction. Using the CAVS model and its submodels, a series of STEALTH calculations were then performed to estimate the response of the NTS unaugmented Dynafrac experiment. Pressure, acceleration and stress time histories and snapshot data were obtained and should aid in the evaluation of these experiments. Crack patterns around the borehole were also calculated and should be valuable in a comparison with the fracture patterns observed during mineback.
Kaczmarski, Krzysztof [University of Tennessee and Rzeszow University of Technology, Poland; Guiochon, Georges A [ORNL
2011-01-01T23:59:59.000Z
In supercritical fluid chromatography (SFC), the significant expansion of the mobile phase along the column causes the formation of axial and radial gradients of temperature. Due to these gradients, the mobile phase density, its viscosity, its velocity, its diffusion coefficients, etc. are not constant throughout the column. This results in a nonuniform flow velocity distribution, itself causing a loss of column efficiency in certain cases, even at low flow rates, as they do in HPLC. At high flow rates, an important deformation of the elution profiles of the sample components may occur. The model previously used to account satisfactorily for the retention of an unsorbed solute in SFC is applied to the modeling of the elution peak profiles of retained compounds. The numerical solution of the combined heat and mass balance equations provides the temperature and the pressure profiles inside the column and values of the retention time and the band profiles of retained compounds that are in excellent agreement with independent experimental data for large value of mobile phase reduced density. At low reduced densities, the band profiles can strongly depend on the column axial distribution of porosity.
A numerical model of aerosol scavenging. Part 2, Simulation of a large city fire
Bradley, M.M.; Molenkamp, C.R.
1991-10-01T23:59:59.000Z
Using a three-dimensional numerical cloud/smoke-plume model, we have simulated the burning of a large, mid-latitude city following a nuclear exchange. The model includes 18 dynamic and microphysical equations that predict the fire-driven airflow, cloud processes, and smoke-cloud interactions. In the simulation, the intense heating from the burning city produces a firestorm with updraft velocities exceeding 60 m/s. Within 15 minutes of ignition, the smoke plume penetrates the tropopause. The updraft triggers a cumulonimbus cloud that produces significant quantities of ice, snow, and hail. These solid hydrometeors, as well as cloud droplets and rain, interact with the smoke particles from the fire. At the end of the one-hour simulation, over 20% of the smoke is in slowly falling snowflakes. If the snow reaches the ground before the flakes completely sublimate (or melt and then evaporate), then only approximately 50% of the smoke will survive the scavenging processes and remain in the atmosphere to affect the global climate.
Eckert, Andreas
2013-05-31T23:59:59.000Z
In this project generic anticline structures have been used for numerical modeling analyses to study the influence of geometrical parameters, fluid flow boundary conditions, in situ stress regime and inter-bedding friction coefficient on geomechanical risks such as fracture reactivation and fracture generation. The resulting stress states for these structures are also used to determine safe drilling directions and a methodology for wellbore trajection optimization is developed that is applicable for non-Andersonian stress states. The results of the fluid flow simulation show that the type of fluid flow boundary condition is of utmost importance and has significant impact on all injection related parameters. It is recommended that further research is conducted to establish a method to quantify the fluid flow boundary conditions for injection applications. The results of the geomechanical simulation show that in situ stress regime is a crucial, if not the most important, factor determining geomechanical risks. For extension and strike slip stress regimes anticline structures should be favored over horizontally layered basin as they feature higher ?P{sub c} magnitudes. If sedimentary basins are tectonically relaxed and their state of stress is characterized by the uni-axial strain model the basin is in exact frictional equilibrium and fluids should not be injected. The results also show that low inter bedding friction coefficients effectively decouple layers resulting in lower ?P{sub c} magnitudes, especially for the compressional stress regime.
Malerba, Lorenzo; Van Walle, Eric [SCK.CEN, Boeretang 200, 2400 Mol (Belgium); Domain, Christophe; Jumel, Stephanie; Van Duysen, Jean-Claude [EDR R and D (France)
2002-07-01T23:59:59.000Z
The REVE (Reactor for Virtual Experiments) project is an international joint effort aimed at developing multi-scale modelling computational toolboxes capable of simulating the behaviour of materials under irradiation at different time and length scales. Well grounded numerical techniques such as molecular dynamics (MD) and Monte Carlo (MC) algorithms, as well as rate equation (RE) and dislocation-defect interaction theory, form the basis on which the project is built. The goal is to put together a suite of integrated codes capable of deducing the changes in macroscopic properties starting from a detailed simulation of the microstructural changes produced by irradiation in materials. To achieve this objective, several European laboratories are closely collaborating, while exchanging data with American and Japanese laboratories currently pursuing similar approaches. The material chosen for the first phase of this project is reactor pressure vessel (RPV) steel, the target macroscopic magnitude to be predicted being the yield strength increase ({delta}{sigma}y) due, essentially, to irradiation-enhanced formation of intragranular solute atom precipitates or clouds, as well as irradiation induced defects in the matrix, such as point defect clusters and dislocation loops. A description of the methodological approach used in the project and its current state is given in the paper. The development of the simulation tools requires a continuous feedback from ad hoc experimental data. In the framework of the REVE project SCK EN has therefore performed a neutron irradiation campaign of model alloys of growing complexity (from pure Fe to binary and ternary systems and a real RPV steel) in the Belgian test reactor BR2 and is currently carrying on the subsequent materials characterisation using its hot cell facilities. The paper gives the details of this experimental programme - probably the first large-scale one devoted to the validation of numerical simulation tools - and presents and discusses the first available results, with a view to their use as feedback for the improvement of the computational modelling. (authors)
Browning, J. R.; Jonkman, J.; Robertson, A.; Goupee, A. J.
2012-11-01T23:59:59.000Z
In 2007, the FAST wind turbine simulation tool, developed and maintained by the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL), was expanded to include capabilities that are suitable for modeling floating offshore wind turbines. In an effort to validate FAST and other offshore wind energy modeling tools, DOE funded the DeepCwind project that tested three prototype floating wind turbines at 1/50th scale in a wave basin, including a semisubmersible, a tension-leg platform, and a spar buoy. This paper describes the use of the results of the spar wave basin tests to calibrate and validate the FAST offshore floating simulation tool, and presents some initial results of simulated dynamic responses of the spar to several combinations of wind and sea states.
Verleysen, Michel
regression (PCR) and partial least squares regression (PLSR). Then, we will propose to incorporate non-linearChemometric calibration of infrared spectrometers: selection and validation of variables by non-linear (step by step) for the selection of spectral variables, using linear regression or neural networks
Apte, Sourabh V.
in rivers, fluidized beds, coal-based oxy-fuel combustion cham- bers, biomass gasifiers, among others is first validated for flow over a fixed sphere at various Reynolds numbers and flow generated by a freely
Numerical Realization of a Shell Model for Impurity Spreading in Plasmas
Tokar, M. Z.; Koltunov, M. [Institute for Energy and Climate Research-Plasma Physics, Research Center Juelich GmbH, Juelich, 52428 (Germany)
2011-09-14T23:59:59.000Z
In plasmas of fusion devices impurity particles are released as a consequence of wall erosion and are seeded deliberately for diverse purposes. Often they enter the plasma volume from small spots and spread away both along and perpendicular to the magnetic field. This process is described by continuity, motion and heat balance equations taking into account such physical processes as ionization by electrons, friction and heating in coulomb collisions with background ions, etc. In present paper we introduce a shell model where solutions of these equations, such as the densities of different impurity ions, are approximated by functions decaying exponentially from the source region due to the ionization into higher charged states. By integrating the original transport equations over several space regions, we get a set of ordinary differential equations describing the time evolution of the characteristic values for the impurity ion densities, fluxes, temperatures, and the dimensions along and across the magnetic field of the clouds where different states are predominantly localized. The equations obtained include time derivatives of complex non-linear combinations of the variables in question. Two numerical approaches to solve such equations are elaborated and compared by considering the spreading of lithium particles in deuterium plasma.
Paradkar, B. S.; Cros, B.; Maynard, G. [Laboratoire de Physique des Gaz et des Plasmas, University Paris Sud 11-CNRS, Orsay (France)] [Laboratoire de Physique des Gaz et des Plasmas, University Paris Sud 11-CNRS, Orsay (France); Mora, P. [Centre de Physique Theorique, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)] [Centre de Physique Theorique, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)
2013-08-15T23:59:59.000Z
Numerical modeling of laser wakefield electron acceleration inside a gas filled dielectric capillary tube is presented. Guiding of a short pulse laser inside a dielectric capillary tube over a long distance (?1 m) and acceleration of an externally injected electron bunch to ultra-relativistic energies (?5-10 GeV) are demonstrated in the quasi-linear regime of laser wakefield acceleration. Two dimensional axisymmetric simulations were performed with the code WAKE-EP (Extended Performances), which allows computationally efficient simulations of such long scale plasma. The code is an upgrade of the quasi-static particle code, WAKE [P. Mora and T. M. Antonsen, Jr., Phys. Plasmas 4, 217 (1997)], to simulate the acceleration of an externally injected electron bunch (including beam loading effect) and propagation of the laser beam inside a dielectric capillary. The influence of the transverse electric field of the plasma wake on the radial loss of the accelerated electrons to the dielectric wall is investigated. The stable acceleration of electrons to multi-GeV energy with a non-resonant laser pulse with a large spot-size is demonstrated.
Walter, M.Todd
.53Â0.57 mm and the combustion gas is normal atmospheric pressure air. A detailed numerical simulationOn the spherically symmetrical combustion of methyl decanoate droplets and comparisons Biodiesel Biofuel Microgravity Numerical Droplet combustion a b s t r a c t This study presents
The VOLNA code for the numerical modelling of tsunami waves: generation, propagation and
of the finite volume scheme implemented in the code. We explain the numerical treatment of the wet is decided on the base of inundation maps which are produced with this type of numerical tools. Finally we and the perspectives for future research presented. Key words: tsunami waves, shallow water equations, tsunami
Lagi, Marco; Bertrand, Karla Z; Bar-Yam, Yaneer
2012-01-01T23:59:59.000Z
Increases in global food prices have led to widespread hunger and social unrest---and an imperative to understand their causes. In a previous paper published in September 2011, we constructed for the first time a dynamic model that quantitatively agreed with food prices. Specifically, the model fit the FAO Food Price Index time series from January 2004 to March 2011, inclusive. The results showed that the dominant causes of price increases during this period were investor speculation and ethanol conversion. The model included investor trend following as well as shifting between commodities, equities and bonds to take advantage of increased expected returns. Here, we extend the food prices model to January 2012, without modifying the model but simply continuing its dynamics. The agreement is still precise, validating both the descriptive and predictive abilities of the analysis. Policy actions are needed to avoid a third speculative bubble that would cause prices to rise above recent peaks by the end of 2012.
RodrÃguez, Rodolfo
Numerical analysis of a finite element method for the axisymmetric eddy current model, 27002, Lugo, Spain The aim of this paper is to analyze a finite element method to solve an eddy current of the method are reported. Keywords: low-frequency harmonic Maxwell equations, eddy current problems, finite
Winsor, Peter
), and a numerical polynya model (NPM) forced by National Center for Environmental Predictions (NCEP) wind fields increases to .83. The NPM computes offshore coastal polynya widths, heat exchange, and ice production is that SAR images processed through the SAR polynya algorithm in combination with the NPM is a powerful tool
Harrison, Mark
1988-01-01T23:59:59.000Z
IMA Journal of Numerical Analysis (1988) 8, 415-433 Finite Element Methods for a Model for Full are given and then a discrete-time, explicit finite element procedure is defined and analysed, with finite on the existence, uniqueness and finite element approximation of the solution of Biot's equations were given in [15
Nemat-Nasser, Sia
Numerical modeling of effect of polyurea on response of steel plates to impulsive loads in direct is studied, focusing on the effects of the relative position of polyurea with respect to the loading plates subjected to uniform blast loads and compared their predictions with experimental results. Bahei
Tandon, Amit
Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John suggested that the mesoscale eddies and mesoscale features play a strong role in carrying heat poleward oceanographers an invaluable tool to assess mesoscale eddies and the Lagrangian characteristics of this mesoscale
Demouchy, Sylvie
Numerical modelling of erosion processes in the Himalayas of Nepal: effects of spatial variations of the morphology of mountain belts. Here we investigate the modalities of defor- mation in Central Nepal on a c that the pattern of uplift in Nepal is mainly dependent on both erodability and fault geometry, rather than
Validation of Innovative Exploration Technologies for Newberry Volcano
Broader source: Energy.gov [DOE]
DOE Geothermal Technologies Peer Review - 2010. Project summary: To effectively combine numerous exploration technologies to gather important data. Once information is combined into 3-D models, a target drilling location will be determined. Deep well capable of finding commercial quantities of geothermal resource will be drilled to validate methodology.
Barthelat, Francois
Numerical and physical modeling of hydraulic structures Hydraulic structures are used to control, their solution is found either by physical hydraulic modeling or, more recently, by numerical modeling significantly reduce turbine efficiency and cause premature mechanical failure when they occur at hydropower
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 3 contains the following appendix sections: Formation and destruction of nitrogen oxides in recovery boilers; Sintering and densification of recovery boiler deposits laboratory data and a rate model; and Experimental data on rates of particulate formation during char bed burning.
Witherspoon, P.A.
2010-01-01T23:59:59.000Z
Mathematical modeling of thermal energy storage in aquifers:presented at the Thermal Energy storage in aquifers1979; Aquifer thermal energy storage—a numerical simulation
Validation of computational models in biomechanics H B Henninger1,2
Utah, University of
of finite element analysis in the 1950s [6, 7], investigators used numerical algorithms to simulate of solid mechanics, these methods were used extensively in computational fluid dynamics (CFD) and heat transfer [10Â12]. As the power of the computer grew, so did the ability to tackle larger and more complex
Numerical study of the mass spectrum in the 2D O(3) sigma model with a theta term
B. Alles; A. Papa
2007-11-12T23:59:59.000Z
It has been conjectured that the mass spectrum of the O(3) non-linear sigma model with a theta term in 2 dimensions may possess an excited state, which decays when theta is lowered from pi below a critical value. Since the direct numerical investigation of the model is prevented by a sign problem, we try to infer some information on the mass spectrum at real theta by studying the model at imaginary theta via analytic continuation. A modified Swendsen-Wang cluster algorithm has been introduced to simulate the model with the theta term.
Mitchell, John Anthony; Epp, David S.; Wittwer, Jonathan W.
2005-10-01T23:59:59.000Z
Damping vibrations is important in the design of some types of inertial sensing devices. One method for adding damping to a device is to use magnetic forces generated by a static magnetic field interacting with eddy currents. In this report, we develop a 2-dimensional finite element model for the analysis of quasistatic eddy currents in a thin sheet of conducting material. The model was used for design and sensitivity analyses of a novel mechanical oscillator that consists of a shuttle mass (thin sheet of conducting material) and a set of folded spring elements. The oscillator is damped through the interaction of a static magnetic field and eddy currents in the shuttle mass. Using a prototype device and Laser Dopler Velocimetry (LDV), measurements were compared to the model in a validation study using simulation based uncertainty analyses. Measurements were found to follow the trends predicted by the model.
An evaluation of pocket-model, numerical readout breath alcohol testing instruments
Van Tassel, William Edward
2004-11-15T23:59:59.000Z
Eight small-scale breath alcohol measurement devices were tested for accuracy, precision and the ability to not yield false positive and false negative readings. These pocket-sized breath testers (PMBTs), which provided numerical readout of Br...
Two-dimensional numerical models of open-top hydrothermal convection at high Rayleigh and Nusselt
Wilcock, William
for Nu up to 5060. Solutions are characterized by an unstable bottom thermal boundary layer where equation. To avoid classical numerical artifacts such as nonphysical oscillatory behavior and artificial
Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.
1998-08-01T23:59:59.000Z
This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 2 contains the last section of Appendix I, Radiative heat transfer in kraft recovery boilers, and the first section of Appendix II, The effect of temperature and residence time on the distribution of carbon, sulfur, and nitrogen between gaseous and condensed phase products from low temperature pyrolysis of kraft black liquor.
Qualification of the ITER CS Quench Detection System using Numerical Modeling
Martovetsky, Nicolai N [ORNL; Radovinsky, Alexey L [ORNL
2013-01-01T23:59:59.000Z
Abstract The ITER Central Solenoid (CS) magnet needs to be protected against overheating of the conductor in the event of the occurrence of a normal zone (NZ). Due to a large amount of stored energy and slow NZ propagation, the NZ needs to be detected and the switchyard needs to open the breakers within 2 s after detection of the NZ. The CS will be discharged on a dump resistor with a time constant of 7.5 s. During operation of the CS and its interaction with the poloidal field (PF) coils and plasma current, the CS experiences large inductive voltages from multiple sources, including nonlinear signals from eddy currents in the vacuum vessel and plasma current variation, that make the task of detecting the resistive signal even more difficult. This inductive voltage needs to be cancelled by quench detection (QD) hardware (e.g., bridges, converters, filters, processors) and appropriate processing of the QD signals to reliably detect NZ initiation and propagation. Two redundant schemes are proposed as the baseline for the CS QD System: 1) A scheme with Regular Voltage Taps (RVT) from triads of Double Pancakes (DP) supplemented by Central Difference Averaging (CDA) and by digital suppression of the inductive voltage from all active coils (the CS and PF coils). Voltage taps are taken from helium outlets at the CS outer diameter. 2)A scheme with Cowound Voltage Taps (CVT) taken from cowound wires routed from the helium inlet at the CS inner diameter. Summary of results of the numerical modeling of the performance of both baseline CS QD systems is presented in this paper. Index Terms Quench detection, Central Solenoid, ITER
A new strategy for discrete element numerical models: 2. Sandbox applications
Sandiford, Mike
and visualized by the modeler. Reliable modeling of geomechanic processes enables the structural interpreter
Mysore, Omar
In this paper, we present the first validation of the virtual source (VS) charge-based compact model for standard cell libraries and large-scale digital circuits. With only a modest number of physically meaningful parameters, ...
T.M. Grace, W.J. Frederick, M. Salcudean, R.A. Wessel
1998-08-01T23:59:59.000Z
This project was initiated in October 1990 with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. Many of these objectives were accomplished at the end of the first five years and documented in a comprehensive report on that work (DOE/CE/40936-T3, 1996). A critical review of recovery boiler modeling, carried out in 1995, concluded that further enhancements of the model were needed to make reliable predictions of key output variables. In addition, there was a need for sufficient understanding of fouling and plugging processes to allow model outputs to be interpreted in terms of the effect on plugging and fouling. As a result, the project was restructured and reinitiated at the end of October 1995, and was completed in June 1997. The entire project is now complete and this report summarizes all of the work done on the project since it was restructured. The key tasks to be accomplished under the restructured project were to (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes; (2) Validate the enhanced furnace models, so that users can have confidence in the results; (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler; and (4) Facilitate the transfer of codes, black liquor submodels, and fundamental knowledge to the U.S. kraft pulp industry.
Validation of Global Weather Forecast and Climate Models Over the North
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps toValidatingCloud Properties Derived from
Sayyar-Rodsari, Bijan; Schweiger, Carl; Hartman, Eric
2007-10-07T23:59:59.000Z
The difficult problems being tackled in the accelerator community are those that are nonlinear, substantially unmodeled, and vary over time. Such problems are ideal candidates for model-based optimization and control if representative models of the problem can be developed that capture the necessary mathematical relations and remain valid throughout the operation region of the system, and through variations in system dynamics. The goal of this proposal is to develop the methodology and the algorithms for building high-fidelity mathematical representations of complex nonlinear systems via constrained training of combined first-principles and neural network models.
A validation test for Adagio through replication of Big Hill and Bayou Choctaw JAS3D models.
Park, Byoung Yoon
2013-06-01T23:59:59.000Z
JAS3D, a three dimensional iterative solid mechanics code, has been used for structural analyses for the Strategic Petroleum Reserve system since the 1990s. JAS3D is no longer supported by Sandia National Laboratories, and has been replaced by Adagio. To validate the transition from JAS3D to Adagio, the existing JAS3D input decks and user subroutines for Bayou Choctaw and Big Hill models were converted for use with Adagio. The calculation results from the Adagio runs are compared to the JAS3D. Since the Adagio results are very similar to the JAS3D results, Adagio is judged to be performing satisfactorily.
Modelling and numerical approximation of a 2.5D set of equations for mesoscale atmospheric processes
Kalise, Dante
2011-01-01T23:59:59.000Z
The set of 3D inviscid primitive equations for the atmosphere is dimensionally reduced by a Discontinuous Galerkin discretization in one horizontal direction. The resulting model is a 2D system of balance laws where with a source term depending on the layering procedure and the choice of coupling fluxes, which is established in terms of upwind considerations. The "2.5D" system is discretized via a WENO-TVD scheme based in a flux limiter centered approach. We study four tests cases related to atmospheric phenomena to analyze the physical validity of the model.
Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.
2014-06-01T23:59:59.000Z
Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.
Bradley, M.M.; Peterson, K.R.; Rodriguez, D.J.
1988-11-17T23:59:59.000Z
During the hours immediately following a nuclear exchange, large fires could inject enormous quantities of smoke into the atmosphere. This smoke, together with dust from surface bursts, would severely restrict visibilities and darken the skies over large areas for days. This, in turn, could impact surface and air operations and systems. These effects could be mitigated by various scavenging mechanisms within the convective clouds that form above the fires. In order to evaluate impacts of post-nuclear-exchange smoke injection, we are developing a three-dimensional numerical smoke plume model (OCTET) to simulate the dynamics and microphysical processes within smoke plumes and convective clouds above large fires. This model is based on the dynamic framework of the Klemp-Wilhelmson (1978) convective storm model and includes parameterizations of scavenging processes. In addition, we are combining results of laboratory research, field experiments, and detailed numerical modeling of cloud microphysical processes in order to better understand smoke scavenging mechanisms. In this brief demonstration of capabilities, we present results from the OCTET model and from a three-dimensional mesoscale model. The smoke plume and fire-induced cloud simulations demonstrate the effects of nucleation scavenging, seasonal variation of atmospheric stability, and various fuel sources. The mesoscale simulations (that use the plume model output as input) demonstrate the mesoscale transport and diffusion of smoke and predict optical depths over the hypothetical target area. No dust effects have been included in these simulations. 2 refs., 8 figs.
Dynamic Modeling and Wavelet-Based Multi-Parametric Tuning and Validation for HVAC Systems
Liang, Shuangshuang
2014-07-10T23:59:59.000Z
. Tummescheit and Eborn [11] discussed the modeling of a thermo-hydraulic model using lumped parameter and distributed parameter methods using commercial software known as Modelica. In 2002, Bendapudi [12] presented a detailed literature review of notable...
Kiryukhin, A.V.; Sugrobov, V.M.
1986-01-21T23:59:59.000Z
The application of the two-dimensional numerical heat-transfer model to the Pauzhetka hydrothermal system allowed us to establish that: (1) a shallow magma body with the anomalous temperature of 700-1000 C and with a volume of 20-30 km{sup 3} may be a heat source for the formation of the Pauzhetka hydrothermal system. (2) The water feeding source of the Pauzhetka hydrothermal system may be meteoric waters which are infiltrated at an average rate of 5-10 kg/s {center_dot} km{sup 2}. The coupling of the numerical heat-transfer model with hydroisotopic data (D,T,{sup 18}O) obtained from the results of testing of exploitation wells, rivers and springs is the basis to understand more clearly the position of recharge areas and the structure of water flows in the hydrothermal system.
Boyer, Edmond
Identification of a sound-insulation layer modelled by fuzzy structure theory - Experimental.fernandez@univ-paris-est.fr Abstract One proposes a novel approach to model sound-insulation layers based on the use of the fuzzy in computational models. The keypoint of the method is the construction of a mean elastoacoustic sound-insulation
A validation of heat and carbon fluxes from highresolution land surface and regional models
D'Andrea, Fabio
) or regional climate models (RCMs) [Alessandri et al., 2007; Steiner et al., 2009]. [3., 2006; Alessandri et al., 2007; Jarlan et al., 2008; Steiner et al., 2009]. However, the SVAT models models do not account for the role of terrestrial vegetation in the carbon cycle variability [Alessandri
Scalar-Scalar Ladder Model in the Unequal-Mass Case. III - Numerical Studies of the P-Wave Case -
Ichio Fukui; Noriaki Setoh
1999-01-21T23:59:59.000Z
The eigenvalue problem for the p-wave bound states formed by two unequal-mass scalar particles through the massive scalar particle exchange is analyzed numerically in the framework of the Bethe-Salpeter ladder model. As in the s-wave case, the eigenvalues of the coupling constant are found to become complex for some mass configurations in some range of the bound state mass. The Bethe-Salpeter amplitudes of the low-lying bound states are also investigated.
Hendrickson, S.M. [ed.] [Lawrence Livermore National Lab., CA (United States)] [ed.; Lawrence Livermore National Lab., CA (United States); Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis] [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis
1994-03-01T23:59:59.000Z
This project, ``Use of International Data Sets to Evaluate and Validate Pathway Assessment Models Applicable to Exposure and Dose Reconstruction at DOE Facilities,`` grew out of several activities being conducted by the Principal Investigator Dr. F Owen Hoffman. One activity was originally part of the Chernobyl Studies Project and began as Task 7.1D, ``Internal Dose From Direct Contamination of Terrestrial Food Sources.`` The objective of Task 7.1D was to (1) establish a collaborative US USSR effort to improve and validate our methods of forecasting doses and dose commitments from the direct contamination of food sources, and (2) perform experiments and validation studies to improve our ability to predict rapidly and accurately the long-term internal dose from the contamination of agricultural soil. The latter was to include the consideration of remedial measures to block contamination of food grown on contaminated soil. The current objective of this project is to evaluate and validate pathway-assessment models applicable to exposure and dose reconstruction at DOE facilities through use of international data sets. This project incorporates the activity of Task 7.1D into a multinational effort to evaluate data used for the prediction of radionuclide transfer through agricultural and aquatic systems to humans. It also includes participation in two multinational studies, BIOMOVS (BIOspheric MOdel Validation Study) with the Swedish National Institute for Radiation Protection and VAMP (VAlidation of Model Predictions) with the International Atomic Energy Agency, that address testing the performance of models of radionuclide transport through foodchains.
Xu, Tianfu; Pruess, Karsten
1998-09-01T23:59:59.000Z
Coupled modeling of subsurface multiphase fluid and heat flow, solute transport and chemical reactions can be used for the assessment of acid mine drainage remediation, mineral deposition, waste disposal sites, hydrothermal convection, contaminant transport, and groundwater quality. Here they present a numerical simulation model, TOUGHREACT, which considers non-isothermal multi-component chemical transport in both liquid and gas phases. A wide range of subsurface thermo-physical-chemical processes is considered. The model can be applied to one-, two- or three-dimensional porous and fractured media with physical and chemical heterogeneity. The model can accommodate any number of chemical species present in liquid, gas and solid phases. A variety of equilibrium chemical reactions is considered, such as aqueous complexation, gas dissolution/exsolution, cation exchange, and surface complexation. Mineral dissolution/precipitation can proceed either subject to local equilibrium or kinetic conditions. The coupled model employs a sequential iteration approach with reasonable computing efficiency. The development of the governing equations and numerical approach is presented along with the discussion of the model implementation and capabilities. The model is verified for a wide range of subsurface physical and chemical processes. The model is well suited for flow and reactive transport in variably saturated porous and fractured media. In the second of this two-part paper, three applications covering a variety of problems are presented to illustrate the capabilities of the model.
A numerical procedure to model and monitor CO2 sequestration in
Santos, Juan
area of research. o We present a methodology integrating numerical simulation of CO2 -brine o The simultaneous flow of brine and CO2 is described by the well-known Black in the brine but the brine is not allowed to vaporize into the CO2 phase. o This formulation uses
Numerical modeling of observed effective flow behavior in unsaturated heterogeneous sands
Wildenschild, Dorthe
, and a stochastic theory were compared to effective retention and hydraulic conductivity characteristics measured slow a response in the outflow rate. An alternative approach involving a combination of arithmetic, deterministic simulations would demand vast computa- tional resources by requiring an extremely dense numerical
Numerical and analytical modelling of entropy noise in a supersonic nozzle with a shock
Boyer, Edmond
and numerical assessments of the indirect noise generated through a nozzle are presented. The configuration. R¨ohle, F. Thiele, B. Noll, The Entropy Wave Generator (EWG): A reference case on entropy noise, Journal of Sound and Vibration 326 (2009) 574-598] where an entropy wave is generated upstream of a nozzle
LABORATORY-NUMERICAL MODEL COMPARISONS OF CANYON FLOWS: A PARAMETER STUDY.
, but the enhanced viscosities needed to obtain numerical stability give boundary layers that are too wide along length scales, one the fluid depth and another a more narrow boundary-layer-like thickness [O(RoBu-1 is the interaction of an oscillatory, along-slope background current with an isolated canyon incised in an otherwise
Overland flow modelling with the Shallow Water Equation using a well balanced numerical scheme
Paris-Sud XI, UniversitÃ© de
or kinematic waves equations, and using either finite volume or finite difference method. We compare these four show that, for relatively simple configurations, kinematic waves equations solved with finite volume; finite differ- ences scheme; kinematic wave equations; shallow water equations; comparison of numerical
Numerical modeling of extreme rogue waves generated by directional energy focusing
Grilli, StÃ©phan T.
of an overturning rogue wave, and analyze the sensitivity of its geometry and kinematics to water depth and maximum. Keywords: Water waves; Numerical wave tank; Extreme wave kinematics; Rogue waves 1. Introduction finely resolved 3D focused overturning waves and analyze their geometry and kinematics. In this paper, we
Diego Misseroni; Francesco Dal Corso; Summer Shahzad; Davide Bigoni
2014-04-03T23:59:59.000Z
Photoelasticity is employed to investigate the stress state near stiff rectangular and rhombohedral inclusions embedded in a 'soft' elastic plate. Results show that the singular stress field predicted by the linear elastic solution for the rigid inclusion model can be generated in reality, with great accuracy, within a material. In particular, experiments: (i.) agree with the fact that the singularity is lower for obtuse than for acute inclusion angles; (ii.) show that the singularity is stronger in Mode II than in Mode I (differently from a notch); (iii.) validate the model of rigid quadrilateral inclusion; (iv.) for thin inclusions, show the presence of boundary layers deeply influencing the stress field, so that the limit case of rigid line inclusion is obtained in strong dependence on the inclusion's shape. The introduced experimental methodology opens the possibility of enhancing the design of thin reinforcements and of analyzing complex situations involving interaction between inclusions and defects.
Behnke, M.; Ellis, A.; Kazachkov, Y.; McCoy, T.; Muljadi, E.; Price, W.; Sanchez-Gasca, J.
2007-09-01T23:59:59.000Z
This paper describes reduced-order, simplified wind turbine models for analyzing the stability impact of large arrays of wind turbines with a single point of network interconnection.
Field observations and numerical model experiments for the snowmelt process at a field site
Ohara, N; Kawas, M L
2006-01-01T23:59:59.000Z
a one dimensional heat transfer model is introduced in orderone dimensional heat transfer model is con- venient forHowever, the simple heat transfer model is a useful tool to
Jones, G.F.; Balcomb, J.D.
1985-01-01T23:59:59.000Z
We have proposed a transient, quasi-two-dimensional, numerical model for interzone heat flow and airflow in passive solar buildings. The paths for heat flow and airflow are through connecting apertures such as doorways, hallways, and stairways. The model includes the major features that influence interzone convection as determined from the results of our flow visualization tests and temperature and airflow measurements taken in more than a dozen passive solar buildings. The model includes laminar and turbulent quasi-steady boundary-layer equations at vertical heated or cooled walls which are coupled to a one-dimensional core model for each zone. The cores in each zone exchange air and energy through the aperture which is modelled by a Bernoulli equation. Preliminary results from the model are in general agreement with data obtained in full-scale buildings and laboratory experiments. The model predicts room-core temperature stratification of about 2/sup 0/C/m (1.1/sup 0/ F/ft) and maximum aperture velocities of 0.08 m/s (15 ft/min.) for a room-to-room temperature difference of 1/sup 0/F.
Validation of the coupled Eta/SSiB model over South America Sin Chan Chou
Xue, Yongkang
the model and to investigate its biases and skill on the simulations of South American climate resolution and 38 vertical layers over the South American continent and part of the adjacent oceans. Analyses of the precipitation annual cycle observed in the central part of South America. The model was integrated continuously
Paris-Sud XI, UniversitÃ© de
1 Development of a new model to predict indoor daylighting : integration in CODYRUN software in the scientific literature for determining indoor daylighting values. They are classified in three categories. The originality of our paper relies on the coupling of several simplified models of indoor daylighting
Validation of a STATCOM Transient Stability Model through Small-Disturbance Stability Studies
Cañizares, Claudio A.
. INTRODUCTION Power system operators are constantly striving to keep power networks secure by guaranteeing models. For instance, the TS models proposed for a series of Flexible AC Transmission Systems (FACTS used in small-disturbance stability studies of large, interconnected power grids as well as microgrids
Thévenaz, Jacques
Double-pulse Brillouin distributed optical fiber sensors: analytical model and experimental-pulse Brillouin optical time-domain analysis (DP-BOTDA) sensors. The proposed model is a tool that provides a full. Keywords: Stimulated Brillouin scattering, distributed optical fiber sensor, temperature sensing, strain
Instrumentation and procedures for validation of synthetic infrared image generation (SIG) models
Salvaggio, Carl
temperature, relative humidity, wind speed, cloud cover, precipitation type and rate, total insolation models are becoming more complex with the incorporation of radiation propagation, thermodynamic by the model mimic many effects seen in actual imagery. The focus of this paper is the definition
Benchmarking Exercises To Validate The Updated ELLWF GoldSim Slit Trench Model
Taylor, G. A.; Hiergesell, R. A.
2013-11-12T23:59:59.000Z
The Savannah River National Laboratory (SRNL) results of the 2008 Performance Assessment (PA) (WSRC, 2008) sensitivity/uncertainty analyses conducted for the trenches located in the EArea LowLevel Waste Facility (ELLWF) were subject to review by the United States Department of Energy (U.S. DOE) Low-Level Waste Disposal Facility Federal Review Group (LFRG) (LFRG, 2008). LFRG comments were generally approving of the use of probabilistic modeling in GoldSim to support the quantitative sensitivity analysis. A recommendation was made, however, that the probabilistic models be revised and updated to bolster their defensibility. SRS committed to addressing those comments and, in response, contracted with Neptune and Company to rewrite the three GoldSim models. The initial portion of this work, development of Slit Trench (ST), Engineered Trench (ET) and Components-in-Grout (CIG) trench GoldSim models, has been completed. The work described in this report utilizes these revised models to test and evaluate the results against the 2008 PORFLOW model results. This was accomplished by first performing a rigorous code-to-code comparison of the PORFLOW and GoldSim codes and then performing a deterministic comparison of the two-dimensional (2D) unsaturated zone and three-dimensional (3D) saturated zone PORFLOW Slit Trench models against results from the one-dimensional (1D) GoldSim Slit Trench model. The results of the code-to-code comparison indicate that when the mechanisms of radioactive decay, partitioning of contaminants between solid and fluid, implementation of specific boundary conditions and the imposition of solubility controls were all tested using identical flow fields, that GoldSim and PORFLOW produce nearly identical results. It is also noted that GoldSim has an advantage over PORFLOW in that it simulates all radionuclides simultaneously - thus avoiding a potential problem as demonstrated in the Case Study (see Section 2.6). Hence, it was concluded that the follow-on work using GoldSim to develop 1D equivalent models of the PORFLOW multi-dimensional models was justified. The comparison of GoldSim 1D equivalent models to PORFLOW multi-dimensional models was made at two locations in the model domains - at the unsaturated-saturated zone interface and at the 100m point of compliance. PORFLOW model results from the 2008 PA were utilized to investigate the comparison. By making iterative adjustments to certain water flux terms in the GoldSim models it was possible to produce contaminant mass fluxes and water concentrations that were highly similar to the PORFLOW model results at the two locations where comparisons were made. Based on the ability of the GoldSim 1D trench models to produce mass flux and concentration curves that are sufficiently similar to multi-dimensional PORFLOW models for all of the evaluated radionuclides and their progeny, it is concluded that the use of the GoldSim 1D equivalent Slit and Engineered trenches models for further probabilistic sensitivity and uncertainty analysis of ELLWF trench units is justified. A revision to the original report was undertaken to correct mislabeling on the y-axes of the compliance point concentration graphs, to modify the terminology used to define the ''blended'' source term Case for the saturated zone to make it consistent with terminology used in the 2008 PA, and to make a more definitive statement regarding the justification of the use of the GoldSim 1D equivalent trench models for follow-on probabilistic sensitivity and uncertainty analysis.
Spectral modeling of two incline cylinders with validation in the time domain
Oswalt, Aaron Jacob
1999-01-01T23:59:59.000Z
Function. 2. 3 Two Input/Single Output System . 2. 4 Conditioned Spectral Analysis. 2. 5 Partial Coherence 2. 6 Formulation of the Nonlinear Model 2. 6. 1 Nonlinear System Form . . 2. 6. 2 Reverse Dynamic Nonlinear System. 2. 6. 3 SDOF Nonlinear...) . . . . . . . . . . . . . . . 15 5 SVSO model for two-input system used to remove the correlated effects of xr(r) . . 18 6 Conditioned spectral model with noise for a two-input / single-output system . . . . . . 20 7 Classification of interference regions for inline...
Spectral modeling of two incline cylinders with validation in the time domain
Oswalt, Aaron Jacob
1999-01-01T23:59:59.000Z
Function. 2. 3 Two Input/Single Output System . 2. 4 Conditioned Spectral Analysis. 2. 5 Partial Coherence 2. 6 Formulation of the Nonlinear Model 2. 6. 1 Nonlinear System Form . . 2. 6. 2 Reverse Dynamic Nonlinear System. 2. 6. 3 SDOF Nonlinear...) . . . . . . . . . . . . . . . 15 5 SVSO model for two-input system used to remove the correlated effects of xr(r) . . 18 6 Conditioned spectral model with noise for a two-input / single-output system . . . . . . 20 7 Classification of interference regions for inline...
Soundfield simulation : the prediction and validation of acoustical behavior with compute models
Saad, Omar, 1974-
2004-01-01T23:59:59.000Z
In the past, acoustical consultants could only try to convince the client/architect that with calculations and geometrical plots they could create an acoustically superb space. Now, by modeling the significant acoustical ...
Validation of a molecular hydrogen penetration model in the electric tokamak
Gourdain, P A
2006-01-01T23:59:59.000Z
chamber of the Electric Tokamak showing bare walls andModel in the Electric Tokamak P. -A. Gourdain a) , L. W.of fusion devices such as tokamaks. In low density plasmas,
Griffith, Daniel Todd
2005-02-17T23:59:59.000Z
The main objective of this work is to demonstrate some new computational methods for estimation, optimization and modeling of dynamical systems that use automatic differentiation. Particular focus will be upon dynamical ...
Relap5-3d model validation and benchmark exercises for advanced gas cooled reactor application
Moore, Eugene James Thomas
2006-08-16T23:59:59.000Z
to material selection and reactor safety. Understanding heat transfer and fluid flow phenomena during normal and transient operation of HTGRs is essential to ensure the adequacy of safety features, such as the reactor cavity cooling system (RCCS). Modeling...
NUMERICAL MODELING FOR THE FORMATION MECHANISM OF 3D TOPOGRAPHY ON MICROBIAL MAT SURFACES
Patel, Harsh Jay
2013-09-27T23:59:59.000Z
determined. A deterministic model includes both a dynamic model, and a static model. Compared to a deterministic solute diffusion model, a stochastic diffusion model has one or more stochastic elements. Concentration diffusion system formulated... solute diffusion equation, which merely appears in the form of a number line, the quasi-2D solute diffusion equation forms a Cartesian grid system. Also, for the explicit quasi-2D solute diffusion equation (Eq. 4), concentration variation is measured...
Experimentally Validated Compatibility Strut and Tie Modeling of Reinforced Concrete Bridge Piers
Scott, Reece Melby
2010-10-12T23:59:59.000Z
as a supplementary tool for capacity analysis purposes. This chapter presents a Compatibility Strut-and-Tie Model (C-STM) that is implemented in commercially available structural analysis software, SAP2000 (1995), to predict the nonlinear response... to the two-point Gauss Truss solution considering the following nonlinear failure mechanisms: (a) flexure steel yielding; (b) transverse steel yielding; and (c) concrete crushing. Each truss is modeled using commercial structural analysis software (SAP2000...
Well-characterized open pool experiment data and analysis for model validation and development.
Sundberg, David W.; Brown, Alexander L.; Blanchat, Thomas K.
2006-12-01T23:59:59.000Z
Four Well-Characterized Open Pool fires were conducted by Fire Science and Technology Department. The focus of the Well-Characterized Open Pool fire series was to provide environmental information for open pool fires on a physics first principal basis. The experiments measured the burning rate of liquid fuel in an open pool and the resultant heat flux to a weapon-sized object and the surrounding environment with well-characterized boundary and initial conditions. Results presented in this report include a general description of test observation (pre- and post-test), wind measurements, fire plume topology, average fuel recession and heat release rates, and incident heat flux to the pool and to the calorimeters. As expected, results of the experiments show a strong correlation between wind conditions, fuel vaporization (mass loss) rate, and incident heat flux to the fuel and ground surface and calorimeters. Numerical fire simulations using both temporally- and spatially-dependant wind boundary conditions were performed using the Vulcan fire code. Comparisons of data to simulation predictions showed similar trends; however, simulation-predicted incident heat fluxes were lower than measured.
Siegel, M.D.; Cheng, W.C. [Sandia National Labs., Albuquerque, NM (United States); Ward, D.B.; Bryan, C.R. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Earth and Planetary Sciences
1995-08-01T23:59:59.000Z
Models used in performance assessment and site characterization activities related to nuclear waste disposal rely on simplified representations of solute/rock interactions, hydrologic flow field and the material properties of the rock layers surrounding the repository. A crucial element in the design of these models is the validity of these simplifying assumptions. An intermediate-scale experiment is being carried out at the Experimental Engineered Test Facility at Los Alamos Laboratory by the Los Alamos and Sandia National Laboratories to develop a strategy to validate key geochemical and hydrological assumptions in performance assessment models used by the Yucca Mountain Site Characterization Project.
Smith, Jordan N.; Hinderliter, Paul M.; Timchalk, Charles; Bartels, M. J.; Poet, Torka S.
2014-08-01T23:59:59.000Z
Sensitivity to chemicals in animals and humans are known to vary with age. Age-related changes in sensitivity to chlorpyrifos have been reported in animal models. A life-stage physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model was developed to computationally predict disposition of CPF and its metabolites, chlorpyrifos-oxon (the ultimate toxicant) and 3,5,6-trichloro-2-pyridinol (TCPy), as well as B-esterase inhibition by chlorpyrifos-oxon in humans. In this model, age-dependent body weight was calculated from a generalized Gompertz function, and compartments (liver, brain, fat, blood, diaphragm, rapid, and slow) were scaled based on body weight from polynomial functions on a fractional body weight basis. Blood flows among compartments were calculated as a constant flow per compartment volume. The life-stage PBPK/PD model was calibrated and tested against controlled adult human exposure studies. Model simulations suggest age-dependent pharmacokinetics and response may exist. At oral doses ? 0.55 mg/kg of chlorpyrifos (significantly higher than environmental exposure levels), 6 mo old children are predicted to have higher levels of chlorpyrifos-oxon in blood and higher levels of red blood cell cholinesterase inhibition compared to adults from equivalent oral doses of chlorpyrifos. At lower doses that are more relevant to environmental exposures, the model predicts that adults will have slightly higher levels of chlorpyrifos-oxon in blood and greater cholinesterase inhibition. This model provides a computational framework for age-comparative simulations that can be utilized to predict CPF disposition and biological response over various postnatal life-stages.
Rao, Rekha R.; Celina, Mathias C.; Giron, Nicholas Henry; Long, Kevin Nicholas; Russick, Edward M.
2015-01-01T23:59:59.000Z
We are developing computational models to help understand manufacturing processes, final properties and aging of structural foam, polyurethane PMDI. Th e resulting model predictions of density and cure gradients from the manufacturing process will be used as input to foam heat transfer and mechanical models. BKC 44306 PMDI-10 and BKC 44307 PMDI-18 are the most prevalent foams used in structural parts. Experiments needed to parameterize models of the reaction kinetics and the equations of motion during the foam blowing stages were described for BKC 44306 PMDI-10 in the first of this report series (Mondy et al. 2014). BKC 44307 PMDI-18 is a new foam that will be used to make relatively dense structural supports via over packing. It uses a different catalyst than those in the BKC 44306 family of foams; hence, we expect that the reaction kineti cs models must be modified. Here we detail the experiments needed to characteriz e the reaction kinetics of BKC 44307 PMDI-18 and suggest parameters for the model based on these experiments. In additi on, the second part of this report describes data taken to provide input to the preliminary nonlinear visco elastic structural response model developed for BKC 44306 PMDI-10 foam. We show that the standard cu re schedule used by KCP does not fully cure the material, and, upon temperature elevation above 150 o C, oxidation or decomposition reactions occur that alter the composition of the foam. These findings suggest that achieving a fully cured foam part with this formulation may be not be possible through therma l curing. As such, visco elastic characterization procedures developed for curing thermosets can provide only approximate material properties, since the state of the material continuously evolves during tests.
Observational and Numerical Modeling Studies of Turbulence on the Texas-Louisiana Continental Shelf
Zhang, Zheng
2013-05-24T23:59:59.000Z
values to CH model values for (a) q= k, (b) P , (c) B, (d) t, (e) 0t, (f) M 2, and (g) N2. . . . . . . . . . . . . . . . . 58 2.19 Ratios of values between the models: (a) SG/CHx; (b) SGx/CH; (c) SG/SGx; (d) CHx... between depths of 6 and 15 m; (b) sum of the turbulent oxygen uxes at the layers. . . . . . . . . . . . . . . . . . . 80 xvii 3.11 (a) observed ; (b) CH modeled ; (c) SG modeled ; (d) observed ; (e) CH modeled ; (f) SG modeled . The SBL and BBL...
Finite Element Modeling and Validation of Residual Stresses in 304 L Girth Welds
Dike, J.J.; Ortega, A.R.; Cadden, C.H.; Rangaswamy, P. Brown, D.
1998-06-01T23:59:59.000Z
Three dimensional finite element simulations of thermal and mechanical response of a 304 L stainless steel pipe subjected to a circumferential autogenous gas tungsten arc weld were used to predict residual stresses in the pipe. Energy is input into the thermal model using a volumetric heat source. Temperature histories from the thermal analysis are used as loads in the mechanical analyses. In the mechanical analyses, a state variable constitutive model was used to describe the material behavior. The model accounts for strain rate, temperature, and load path histories. The predicted stresses are compared with x-ray diffraction determinations of residual stress in the hoop and circumferential directions on the outside surface of the pipe. Calculated stress profiles fell within the measured data. Reasons for observed scatter in measured stresses are discussed.
Tesfatsion, Leigh
Data gathering to build and validate small-scale social models for simulation. Two ways: strict.rouchier@univmed.fr Kyoto, 2005 - 10 - 13 Modelling and the search for realism Social simulation using multi-agent paradigm (sometimes called "agent-based simulation" or "simulation with agents") has developed quickly in the last
Validating a physics-based back-of-the-envelope climate model with state-of-the-art data
Benestad, Rasmus E
2013-01-01T23:59:59.000Z
An old conceptual physics-based back-of-the-envelope model for greenhouse effect is revisited and validated against state-of-the-art reanalyses. Untraditional diagnostics show a physically consistent picture, for which the state of earth's climate is constrained by well-known physical principles, such as energy balance, flow and, conservation. Greenhouse gas concentrations affect the atmospheric optical depth for infrared radiation, and increased opacity implies higher altitude from which earth's equivalent bulk heat loss takes place without being re-absorbed. Such increase is seen in the reanalyses. There has also been a reduction in the correlation between the spatial structure of outgoing long-wave radiation and surface temperature, consistent with increasingly more processes interfering with the upwelling infrared light before it reaches the top of the atmosphere. State-of-the-art reanalyses further imply increases in the overturning in the troposphere, consistent with a constant and continuous vertical e...
Numerical Modeling of Diffusion in Fractured Media for Gas-Injection
Firoozabadi, Abbas
; Arana 2001; Darvish et al. 2006). Coats (1989) has modeled the effect of diffusion in dual- porosity
A numerical model for the coupled long-term evolution of salt marshes and tidal flats
Fagherazzi, Sergio
-shore mudflat model that takes into account tidal effects; Waeles et al. [2004] incor- porated in the same
A Numerical Model for Miscible Displacement of Multi-Component Reactive Species
Paris-Sud XI, UniversitÃ© de
. Azarouala a Water Department/Groundwater and Geochemistry Modeling, BRGM (French Geological Survey) 3 of our approach. Therefore, the model may prove useful for many practical applications. 1. INTRODUCTION Demands to undertake modeling analysis of coupled groundwater ow, solute transport, and reactive water
Relap5-3d model validation and benchmark exercises for advanced gas cooled reactor application
Moore, Eugene James Thomas
2006-08-16T23:59:59.000Z
abilities of system analysis codes, used to develop an understanding of light water reactor phenomenology, need to be proven for HTGRs. RELAP5-3D v2.3.6 is used to generate two reactor plant models for a code-to-code and a code-to-experiment benchmark...
Validation of winter chill models using historic records of walnut phenology Eike Luedeling a,
Zhang, Minghua
is only possible under certain conditions using labor-intensive cultural practices (Balandier et al., 1993 models yielded good predictions, or where their failure was not obvious, growers rarely transitioned stage dates. This method simultaneously estimates Agricultural and Forest Meteorology 149 (2009) 1854
Collins, Kent Michael
1995-01-01T23:59:59.000Z
.05 significance level. Analysis of observed 85th percentile speeds revealed that the current speed-profile model fits the observed data reasonably well. Hypothesis tests of mean observed 85th percentile speeds on tangents resulted in the conclusion that the mean...
VALIDATION OF THE SUNY SATELLITE MODEL IN A METEOSAT ENVIRONMENT Richard Perez
Perez, Richard R.
]. In this paper we evaluate the model's performance with another set of satellites: the European Meteosat 5 and 7 NREL, 1617 Cole Blvd. Golden, CO 80847 David_renne@nrel.gov Shannon Cowlin NREL Shannon_cowlin@nrel.gov Ray George NREL Ray_george@nrel.gov Bibek Bandyopadhyay Solar Energy Centre New Delhi, India bbibek
Griffith, Daniel Todd
2005-02-17T23:59:59.000Z
computation and evaluation of partial derivatives with minimal user coding. The key results in this dissertation details the use of OCEA through a number of computational studies in estimation and dynamical modeling. Several prototype problems are studied... Embedding Method), has been recently developed which shows promise for efficient computation and evaluation of partial derivatives. For a rather arbitrary sequentially substituted set of functions, coded in FORTRAN 90, OCEA invokes operator overloading...
Dooley, S.; Curran, H.J.; Simmie, J.M. [Combustion Chemistry Centre, National University of Ireland, Galway (Ireland)
2008-04-15T23:59:59.000Z
The autoignition of methyl butanoate has been studied at 1 and 4 atm in a shock tube over the temperature range 1250-1760 K at equivalence ratios of 1.5, 1.0, 0.5, and 0.25 at fuel concentrations of 1.0 and 1.5%. These measurements are complemented by autoignition data from a rapid compression machine over the temperature range 640-949 K at compressed gas pressures of 10, 20, and 40 atm and at varying equivalence ratios of 1.0, 0.5, and 0.33 using fuel concentrations of 1.59 and 3.13%. The autoignition of methyl butanoate is observed to follow Arrhenius-like temperature dependence over all conditions studied. These data, together with speciation data reported in the literature in a flow reactor, a jet-stirred reactor, and an opposed-flow diffusion flame, were used to produce a detailed chemical kinetic model. It was found that the model correctly simulated the effect of change in equivalence ratio, fuel fraction, and pressure for shock tube ignition delays. The agreement with rapid compression machine ignition delays is less accurate, although the qualitative agreement is reasonable. The model reproduces most speciation data with good accuracy. In addition, the important reaction pathways over each regime have been elucidated by both sensitivity and flux analyses. (author)
Ruiz, Elisa; Martinez, Pedro J. [Universidad Miguel Hernandez - Edificio Torreblanca, Avda. de la Universidad s/n, 03202 Elche (Spain)
2010-01-15T23:59:59.000Z
In the case of private outdoor swimming pools, seldom larger than 100 m{sup 2}, conventional auxiliary heating systems are being installed less and less. Solar heating is an option to extend the swimming season. The temperature evolution of an open-air swimming pool highly depends on the wind speed directly on the water surface, which at the same time is influenced by the surroundings of the pool. In this paper, the TRNSYS model of a private open-air pool with a 50-m{sup 2} surface was validated by registering the water temperature evolution and the meteorological data at the pool site. Evaporation is the main component of energy loss in swimming pools. Six different sets of constants found in literature were considered to evaluate the evaporative heat transfer coefficient with the purpose of finding the most suitable one for the TRNSYS pool model. In order to do that, the evolution of the pool water temperature predicted by the TRNSYS pool model was compared with the experimentally registered one. The simulation with TRNSYS of the total system, including the swimming pool and the absorber circuit integrated into the existing filter circuit, provided information regarding the increase of the pool temperature for different collector areas during the swimming season. This knowledge, together with the economic costs, support the decision about the absorber field size. (author)
Not Available
1980-09-01T23:59:59.000Z
Nineteen papers were presented at the workshop on modeling thermohydrologic flow in fractured masses. This workshop was a result of the interest currently being given to the isolation of nuclear wastes in geologic formations. Included in these proceedings are eighteen of the presentations, one abstract and summaries of the panel discussions. The papers are listed under the following categories: introduction; overviews; fracture modelings; repository studies; geothermal models; and recent developments. Eighteen of the papers have been abstracted and indexed.
THE STATE OF THE ART OF NUMERICAL MODELING OF THERMOHYDROLOGIC FLOW IN FRACTURED ROCK MASSES
Wang, J.S.Y.
2013-01-01T23:59:59.000Z
Doughty, 1979a, Aquifer thermal energy storage--a numericalical modeling of thermal energy storage in aquifers.Presented at the Thermal Energy Storage in Aquifers
Numerical simulations of the internal shock model in magnetized relativistic jets of blazars
Rueda-Becerril, Jesus M; Aloy, Miguel A
2015-01-01T23:59:59.000Z
The internal shocks scenario in relativistic jets is used to explain the variability of the blazar emission. Recent studies have shown that the magnetic field significantly alters the shell collision dynamics, producing a variety of spectral energy distributions and light-curves patterns. However, the role played by magnetization in such emission processes is still not entirely understood. In this work we numerically solve the magnetohydodynamic evolution of the magnetized shells collision, and determine the influence of the magnetization on the observed radiation. Our procedure consists in systematically varying the shell Lorentz factor, relative velocity, and viewing angle. The calculations needed to produce the whole broadband spectral energy distributions and light-curves are computationally expensive, and are achieved using a high-performance parallel code.
Bailey, Owen; Creighton, Charles; Firestone, Ryan; Marnay, Chris; Stadler, Michael
2003-02-01T23:59:59.000Z
This report describes a Berkeley Lab effort to model the economics and operation of small-scale (<500 kW) on-site electricity generators based on real-world installations at several example customer sites. This work builds upon the previous development of the Distributed Energy Resource Customer Adoption Model (DER-CAM), a tool designed to find the optimal combination of installed equipment, and idealized operating schedule, that would minimize the site's energy bills, given performance and cost data on available DER technologies, utility tariffs, and site electrical and thermal loads over a historic test period, usually a recent year. This study offered the first opportunity to apply DER-CAM in a real-world setting and evaluate its modeling results. DER-CAM has three possible applications: first, it can be used to guide choices of equipment at specific sites, or provide general solutions for example sites and propose good choices for sites with similar circumstances; second, it can additionally provide the basis for the operations of installed on-site generation; and third, it can be used to assess the market potential of technologies by anticipating which kinds of customers might find various technologies attractive. A list of approximately 90 DER candidate sites was compiled and each site's DER characteristics and their willingness to volunteer information was assessed, producing detailed information on about 15 sites of which five sites were analyzed in depth. The five sites were not intended to provide a random sample, rather they were chosen to provide some diversity of business activity, geography, and technology. More importantly, they were chosen in the hope of finding examples of true business decisions made based on somewhat sophisticated analyses, and pilot or demonstration projects were avoided. Information on the benefits and pitfalls of implementing a DER system was also presented from an additional ten sites including agriculture, education, health care, airport, and manufacturing facilities.
Aghdam, E. Abdi [Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil (Iran); Kabir, M.M. [Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil (Iran); Department of Engineering, Islamic Azad University, Aliabad Katoul Branch, Golestan (Iran)
2010-02-15T23:59:59.000Z
Blowby and gas flow through the cylinder-piston-ring crevices are phenomena that affect the engine performance and exhaust emissions. Also these phenomena influence the cylinder pressure and temperature and the charge amount during a cycle. The study and validation of a sub-model for these phenomena in the absence of engine combustion deducts all effects arisen from the combustion event. During the current study, blowby sub-model and gas flow through crevices under motoring conditions has been noticed using a volume-orifice theory and the experimental results measured from a research engine. Blowby geometric parameters, consisting of a few critical cross-section areas (orifice areas) and volumes (top land and inter-ring crevice volumes), were measured in ambient temperature and corrected for hot running conditions. The cylinder pressure during cycle was measured by a piezoelectric pressure transducer and the low pressure parts of the cycle were measured using a piezoresistive pressure transducer for referencing purposes. The obtained results show a very good agreement between experimentally measured pressure data and model output for three compression ratios of 7.6, 10.2, 12.4 and three engine speeds of 750, 1500 and 2000 rpm, so that the maximum deviation was almost 5%. The model predicted that the maximum mass loss increased with increase of compression ratio and decreased with increase of engine speed. Also the peak mass loss position happened within the range of 3-9 CA after top dead center. After occurrence of the maximum loss, a reverse flow from the top land crevice into the cylinder was predicted in the model. (author)
A Complete Transport Validated Model on a Zeolite Membrane for Carbon Dioxide Permeance and Capture
Gkanas, Evangelos I; Stubos, Athanasios K; Makridis, Sofoklis S
2013-01-01T23:59:59.000Z
The CO2 emissions from major industries cause serious global environment problems and their mitigation is urgently needed. The use of zeolite membranes is a very efficient way in order to capture CO2 from some flue gases. The dominant transport mechanism at low temperature andor high pressure is the diffusion through the membrane. This procedure can be divided in three steps: Adsorption of the molecules of the species in the surface of the membrane, then a driving force gives a path where the species follow inside the membrane and finally the species desorbed from the surface of the membrane. The current work is aimed at developing a simulation model for the CO2 transport through a zeolite membrane and estimate the diffusion phenomenon through a very thin membrane of 150 nm in a Wicke-Kallenbach cell. The cell is cylindrical in shape with diameter of 19 mm and consists of a retentate gas chamber, a permeate gas chamber which are separated by a cylindrical zeolite membrane. This apparatus have been modeled wit...
Breault, Ronald W, [U.S. DOE; Huckaby, Ernest D. [U.S. DOE; Shadle, Lawrence J [U.S. DOE; Spenik, James L. [REM Engineering PLLC
2013-01-01T23:59:59.000Z
The National Energy Technology Laboratory is investigating a new process for CO{sub 2} capture from large sources such as utility power generation facilities as an alternative to liquid amine based absorption processes. Many, but not all of these advanced dry processes are based upon sorbents composed of supported polyamines. In this analysis, experiments have been conducted in a small facility at different temperatures and compared to CFD reactor predictions using kinetics obtained from TGA tests. This particular investigation compares the predicted performance and the experimental performance of one of these new class of sorbents in a fluidized bed reactor. In the experiment, the sorbent absorbs CO{sub 2} from simulated flue gas in a riser reactor, separates the carbonated particles from the de-carbonated flue gas in a cyclone and then regenerates the sorbent, creating a concentrated stream of pure CO{sub 2} for sequestration. In this work, experimental measurements of adsorption are compared to predictions from a 3-dimensional non-isothermal reacting multiphase flow model. The effects of the gas flow rate and reactor temperature are explored. It is shown that the time duration for CO{sub 2} adsorption decreased for an increase in the gas flow. The details of the experimental facility and the model as well as the comparative analysis between the data and the simulation results are discussed.
Buckholtz, H.T.; Biermann, A.H.
1980-01-01T23:59:59.000Z
A computational model to simulate the dispersion and coagulation of aerosols emitted from coal-fired power plants was constructed. In modeling the dispersion of the aerosol, turbulent diffusion and wind-driven advection are treated by a finite-difference method. Molecular coagulation is incorporated in the model to follow shifts in the particle-size distribution. Particulate coagulation is mathematically described by Timiskii's equation. The relevent semi-empirical work of Smirnov is incorporated in the model to provide for the coagultion constant. Input for the model is a bimodal, particle-size distribution measured at an operating coal-fired power plant. Simulations indicate that dispersion competes against coagulation mechanisms to maintain the bimodal shaped distribution for 32 km. Turbulence and particle settling tend to enchance coagulation effects. The size-dependent spatial segregation of particles within the plume is predicted.
You, Xinli; Pratt, Lawrence R; Pesika, Noshir; Aritakula, Kalika M; Rick, Steven W
2012-01-01T23:59:59.000Z
Reported here are experimental and molecular dynamics simulation results for propylene carbonate as a solvent for electrochemical double-layer capacitors based on carbon nanotube forests. Propylene carbonate (PC) wets graphite with a contact angle of 31{\\deg}. Molecular dynamics results agree with this result after reduction of the strength of dispersion attractions to the graphite C atoms by 40%, relative to the models used initially. A simulated nano-scale PC droplet on graphite displays a pronounced layering tendency and an Aztex pyramid structure for the droplet. Computed surface tensions of the PC liquid-vapor interface permit an extrapolative estimate of the critical temperature of PC that is accurate to about 3%. Average PC molecule binding energies, and their variances, are evaluated, and the distribution of binding energies is closely Gaussian. Evaluation of the density of the coexisting vapor then permits estimation of the excluded volume contribution to the PC chemical potential, and that contribut...
Radiation Damage in Nuclear Fuel for Advanced Burner Reactors: Modeling and Experimental Validation
Jensen, Niels Gronbech; Asta, Mark; Ozolins, Nigel Browning'Vidvuds; de Walle, Axel van; Wolverton, Christopher
2011-12-29T23:59:59.000Z
The consortium has completed its existence and we are here highlighting work and accomplishments. As outlined in the proposal, the objective of the work was to advance the theoretical understanding of advanced nuclear fuel materials (oxides) toward a comprehensive modeling strategy that incorporates the different relevant scales involved in radiation damage in oxide fuels. Approaching this we set out to investigate and develop a set of directions: 1) Fission fragment and ion trajectory studies through advanced molecular dynamics methods that allow for statistical multi-scale simulations. This work also includes an investigation of appropriate interatomic force fields useful for the energetic multi-scale phenomena of high energy collisions; 2) Studies of defect and gas bubble formation through electronic structure and Monte Carlo simulations; and 3) an experimental component for the characterization of materials such that comparisons can be obtained between theory and experiment.
Validation Analysis of the Groundwater Flow and Transport Model of the Central Nevada Test Area
A. Hassan; J. Chapman; H. Bekhit; B. Lyles; K. Pohlmann
2006-09-30T23:59:59.000Z
The Central Nevada Test Area (CNTA) is a U.S. Department of Energy (DOE) site undergoing environmental restoration. The CNTA is located about 95 km northeast of Tonopah, Nevada, and 175 km southwest of Ely, Nevada (Figure 1.1). It was the site of the Faultless underground nuclear test conducted by the U.S. Atomic Energy Commission (DOE's predecessor agency) in January 1968. The purposes of this test were to gauge the seismic effects of a relatively large, high-yield detonation completed in Hot Creek Valley (outside the Nevada Test Site [NTS]) and to determine the suitability of the site for future large detonations. The yield of the Faultless underground nuclear test was between 200 kilotons and 1 megaton (DOE, 2000). A three-dimensional flow and transport model was created for the CNTA site (Pohlmann et al., 1999) and determined acceptable by DOE and the Nevada Division of Environmental Protection (NDEP) for predicting contaminant boundaries for the site.
Fuchs, E.F.; You, Y.; Roesler, D.J. [Univ. of Colorado, Boulder, CO (United States)] [Univ. of Colorado, Boulder, CO (United States)
1999-04-01T23:59:59.000Z
This paper proposes a new model for three-phase transformers with three legs with and without tank under DC bias based on electric and magnetic circuit theory. For the calculation of the nonsinusoidal no-load currents, a combination of time and frequency domains is used. The analysis shows that (1) asymmetric three-phase transformers with three legs generate magnetizing currents with triplen harmonics not being of the zero-sequence type. (2) The wave shapes of the three magnetizing currents of (asymmetric) transformers are dependent on the phase sequence. (3) The magnetic history of transformer magnetization -- due to residual magnetization and hysteresis of the tank -- cannot be ignored if a DC bias is present and the magnetic influence of the tank is relatively strong, e.g., for oil-cooled transformers. (4) Symmetric three-phase transformers with three legs generate no-load currents without triplen harmonics. (5) The effects of DC bias currents (e.g., reactive power demand, harmonic distortion) can be suppressed employing symmetric three-phase transformers with three legs including tank. Measurements corroborate computational results; thus this nonlinear model is valid and accurate.
Lusk, Miriam Beatriz
2011-12-31T23:59:59.000Z
To capture the fracture process and non-linear behavior at the element and structural level of granular materials, concrete, under the presence of pre-existing imperfections, a constitutive model and a mesh free method is ...
Airborne observations and numerical modeling of fetch- limited waves in the Gulf of Tehuantepec
Romero, Leonel
2008-01-01T23:59:59.000Z
velocity scaling in wind wave generation. Boundary-Layerlinear theory of of wind wave generation applied to waveSource terms in a third-generation wind wave model. J. Phys.
Numerical Modeling of Fractured Shale-Gas and Tight-Gas Reservoirs Using Unstructured Grids
Olorode, Olufemi Morounfopefoluwa
2012-02-14T23:59:59.000Z
Various models featuring horizontal wells with multiple induced fractures have been proposed to characterize flow behavior over time in tight gas and shale gas systems. Currently, there is little consensus regarding the effects of non...
Numerical Modeling of the Transient Thermal Interference of Vertical U-Tube Haet Exchangers
Muraya, Norman K.
1994-01-01T23:59:59.000Z
Non-linear finite element models were developed to simulate transient heat and mass transfer in the soil surrounding the ground heat exchangers of ground-coupled heat pumps (GCHPs) operating in the cooling mode. Parametric studies were performed...
NUMERICAL MODELING FOR THE FORMATION MECHANISM OF 3D TOPOGRAPHY ON MICROBIAL MAT SURFACES
Patel, Harsh Jay
2013-09-27T23:59:59.000Z
, an innovative modeling approach was employed that focuses on the interface growth of the microbial mat surfaces using a combined stochastic and deterministic approach. A range of different initial conditions were simulated to evaluate the 3D topography evolution...
THE STATE OF THE ART OF NUMERICAL MODELING OF THERMOHYDROLOGIC FLOW IN FRACTURED ROCK MASSES
Wang, J.S.Y.
2013-01-01T23:59:59.000Z
studies related to the Cerro Prieto Field: Proceedings, 1stSymposium on the Cerro Prieto Geothermal Field, San Diego,modeling studies of the Cerro Prieto Reservoir--A progress
Paris-Sud XI, Université de
of underground storage facilities for nuclear waste. The processes involved in near-field models are extremely field u : [0, T ] × R3 and a pressure field p : [0, T ] × R such that - ·(u) + b p = f, in [0
Zeng, Yi
Mathematical models of batteries which make use of the intercalation of a species into a solid phase need to solve the corresponding mass transfer problem. Because solving this equation can significantly add to the ...
Numerical Modeling of the Transient Thermal Interference of Vertical U-Tube Haet Exchangers
Muraya, Norman K.
Non-linear finite element models were developed to simulate transient heat and mass transfer in the soil surrounding the ground heat exchangers of ground-coupled heat pumps (GCHPs) operating in the cooling mode. Parametric studies were performed...
Cirpka, Olaf Arie
vicinity Abandoned wellCO2 2 #12;University of Stuttgart IWS, Department of Hydromechanics and Modelling discretization cap rock precipitated calcite reservoir radius of several meters injection of bacteria, urea
Numerical modeling of fluid flow and time-lapse seismics to monitor ...
santos
May 30, 2014 ... including the presence of shale seals and fractures and fractal variations of the ... In the Black-Oil model employed, brine is NOT present, OIL is.
Numerical and analytical modeling of heat transfer between fluid and fractured rocks
Li, Wei, S.M. Massachusetts Institute of Technology
2014-01-01T23:59:59.000Z
Modeling of heat transfer between fluid and fractured rocks is of particular importance for energy extraction analysis in EGS, and therefore represents a critical component of EGS design and performance evaluation. In ...
Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d'Hères (France)
2014-01-29T23:59:59.000Z
In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.
Final Report: A Model Management System for Numerical Simulations of Subsurface Processes
Zachmann, David
2013-10-07T23:59:59.000Z
The DOE and several other Federal agencies have committed significant resources to support the development of a large number of mathematical models for studying subsurface science problems such as groundwater flow, fate of contaminants and carbon sequestration, to mention only a few. This project provides new tools to help decision makers and stakeholders in subsurface science related problems to select an appropriate set of simulation models for a given field application.
Dark matter, neutrino masses and high scale validity of an inert Higgs doublet model
Nabarun Chakrabarty; Dilip Kumar Ghosh; Biswarup Mukhopadhyaya; Ipsita Saha
2015-01-15T23:59:59.000Z
We consider a two-Higgs doublet scenario containing three $SU(2)_L$ singlet heavy neutrinos with Majorana masses. The second scalar doublet as well as the neutrinos are odd under a $Z_2$ symmetry. This scenario not only generates Majorana masses for the light neutrinos radiatively but also makes the lighter of the neutral $Z_2$-odd scalars an eligible dark matter candidate, in addition to triggering leptogenesis at the scale of the heavy neutrino masses. Taking two representative values of this mass scale, we identify the allowed regions of the parameter space of the model, which are consistent with all dark matter constraints. At the same time, the running of quartic couplings in the scalar potential to high scales is studied, thus subjecting the regions consistent with dark matter constraints to further requirements of vacuum stability, perturbativity and unitarity. It is found that part of the parameter space is consistent with all of these requirements all the way up to the Planck scale, and also yields the correct signal strength in the diphoton channel for the scalar observed at the Large Hadron Collider.
and free surface models and a global heat transfer model, with moving boundaries. An axisymmetric fluid to determine flow field, after the phase boundaries have been determined, by the heat transfer model. A finite field, from which temperature gradients are determined. The heat transfer model is furthermore expanded
J. E. O'Brien; M. G. McKellar; G. L. Hawkes; C. M. Stoots
2007-07-01T23:59:59.000Z
A one-dimensional chemical equilibrium model has been developed for analysis of simultaneous high-temperature electrolysis of steam and carbon dioxide (coelectrolysis) for the direct production of syngas, a mixture of hydrogen and carbon monoxide. The model assumes local chemical equilibrium among the four process-gas species via the shift reaction. For adiabatic or specified-heat-transfer conditions, the electrolyzer model allows for the determination of coelectrolysis outlet temperature, composition (anode and cathode sides), mean Nernst potential, operating voltage and electrolyzer power based on specified inlet gas flow rates, heat loss or gain, current density, and cell area-specific resistance. Alternately, for isothermal operation, it allows for determination of outlet composition, mean Nernst potential, operating voltage, electrolyzer power, and the isothermal heat requirement for specified inlet gas flow rates, operating temperature, current density and area-specific resistance. This model has been developed for incorporation into a system-analysis code from which the overall performance of large-scale coelectrolysis plants can be evaluated. The one-dimensional co-electrolysis model has been validated by comparison with results obtained from a 3-D computational fluid dynamics model and by comparison with experimental results.
Min, Kyoung
2013-07-16T23:59:59.000Z
are studied using a coupled thermo-hydro-mechanical (THM) analysis. The models are used to simulate microscopic and macroscopic fracture behaviors of laboratory-scale uniaxial and triaxial experiments on rock using an elastic/brittle damage model considering...
Synthesis of Numerical Methods for Modeling Wave Energy Converter-Point Absorbers: Preprint
Li, Y.; Yu, Y. H.
2012-05-01T23:59:59.000Z
During the past few decades, wave energy has received significant attention among all ocean energy formats. Industry has proposed hundreds of prototypes such as an oscillating water column, a point absorber, an overtopping system, and a bottom-hinged system. In particular, many researchers have focused on modeling the floating-point absorber as the technology to extract wave energy. Several modeling methods have been used such as the analytical method, the boundary-integral equation method, the Navier-Stokes equations method, and the empirical method. However, no standardized method has been decided. To assist the development of wave energy conversion technologies, this report reviews the methods for modeling the floating-point absorber.
Numerical model for the vacuum pyrolysis of scrap tires in batch reactors
Yang, J.; Tanguy, P.A.; Roy, C. [Univ. Laval, Quebec, PQ (Canada). Dept. de Genie Chimique] [Univ. Laval, Quebec, PQ (Canada). Dept. de Genie Chimique
1995-06-01T23:59:59.000Z
A quantitative model for scrap tire pyrolysis in a batch scale reactor developed comprises the following basic phenomena: conduction inside tire particles; conduction, convection, and radiation between the feedstock particles or between the fluids and the particles; tire pyrolysis reaction; exothermicity and endothermicity caused by tire decomposition and volatilization; and the variation of the composition and the thermal properties of tire particles. This model was used to predict the transient temperature and density distributions in the bed of particles, the volatile product evolution rate, the mass change, the energy consumption during the pyrolysis process, and the pressure history in a tire pyrolysis reactor with a load of 1 kg. The model predictions agree well with independent experimental data.
None
2005-07-01T23:59:59.000Z
This work was carried out to understand the behavior of the solid and gas phases in a CFB riser. Only the riser is modeled as a straight pipe. A model with linear algebraic approximation to solids viscosity of the form, {musubs} = 5.34{epsisubs}, ({espisubs} is the solids volume fraction) with an appropriate boundary condition at the wall obtained by approximate momentum balance solution at the wall to acount for the solids recirculation is tested against experimental results. The work done was to predict the flow patterns in the CFB risers from available experimental data, including data from a 7.5-cm-ID CFB riser at the Illinois Institute of Technology and data from a 20.0-cm-ID CFB riser at the Particulate Solid Research, Inc., facility. This research aims at modeling the removal of hydrogen sulfide from hot coal gas using zinc oxide as the sorbent in a circulating fluidized bed and in the process indentifying the parameters that affect the performance of the sulfidation reactor. Two different gas-solid reaction models, the unreacted shrinking core (USC) and the grain model were applied to take into account chemical reaction resistances. Also two different approaches were used to affect the hydrodynamics of the process streams. The first model takes into account the effect of micro-scale particle clustering by adjusting the gas-particle drag law and the second one assumes a turbulent core with pseudo-steady state boundary condition at the wall. A comparison is made with experimental results.
Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d'Hères (France); Bradu, Benjamin [CERN, CH-1211 Genève 23 (Switzerland)
2014-01-29T23:59:59.000Z
In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.
Numerical Modelling of a Pulse Combustion Burner: Limiting Conditions of Stable
Vuik, Kees
-called thermal pulse combustor. By integrating the model equations in time it is possible to predict whether A thermal pulse combustion. Figure 1 gives a schematic representation of such a thermal pulse combustor combustors may give important guide- lines on how design parameters should be chosen. This paper gives
A numerical procedure to model and monitor CO2 sequestration in
Santos, Juan
sequestration over very long periods of time. · The analysis of CO2 underground storage safety in the long term procedure to model and monitor CO2 sequestration in aquifers p. #12;Introduction. I · Storage of CO2 (31.6C, 7.38 MPa). · First industrial scale CO2 injection project: Sleipner gas field (North Sea
A numerical procedure to model and monitor CO2 sequestration in aquifers
Santos, Juan
sequestration over very long periods of time. The analysis of CO2 underground storage safety in the long term procedure to model and monitor CO2 sequestration in aquifers p. #12;Introduction. I Storage of CO2 (31.6C, 7.38 MPa). First industrial scale CO2 injection project: Sleipner gas field (North Sea
A multiple layer numerical model of the formation of the low-level jet
Shen, Tsu-Cheng
1980-01-01T23:59:59.000Z
310 320 e(kj Fig. 3. The initial vertical distribution of potential tempera- ture in the model . Table 3. The vertical distribution of the variables used for setting the initial conditions. LEVEL k (m s ) kh(m s ) u(ms ) v(ms ) w(ms ) e (k) 00 p...
NUMERICAL MODELLING OF MICROORGANISMS DISPERSION IN URBAN AREA: APPLICATION TO LEGIONELLA.
Paris-Sud XI, UniversitÃ© de
with transmission of an infectious agent from cooling towers (CT). During the episode that occured in Pas to contaminated cooling towers system may occur over distance larger than 10km. In addition, most cooling towers dispersion from a virtual cooling tower at the same location. The biological model has been activated
Evaluation of a semi-implicit numerical algorithm for a rate-dependent ductile failure model.
Zocher, M. A. (Marvin Anthony); Zuo, Q. K. (Qiuhai K.); Mason, T. A. (Thomas A.)
2002-09-01T23:59:59.000Z
A survey conducted in the mid-80's revealed that the mathematical descriptions of ductile fracture tended to apply to either tensile tests or spa11 tests. The objective behind the development of the TEPLA was then a unification of these disparate phenomena into a single model.
Numerical Modeling of Nonlinear Coupling between Lines/Beams with Multiple Floating Bodies
Yang, Chan K.
2010-07-14T23:59:59.000Z
to be capable of modeling the tendon disconnection both at the top and the bottom connection as well as the down stroke behavior for the pinned bottom joint. The performance of the tie-down clamp of derrick is also investigated by using six degrees of freedom...
Paris-Sud XI, UniversitÃ© de
as on how short-term mechanisms Â and policy action Â can smooth the negative impacts of energy price shocks1 The Resilience of the Indian Economy to Rising Oil Prices as a Validation Test for a Global Energy-Environment-Economy CGE Model CÃ©line Guivarcha, * , StÃ©phane Hallegattea,b , Renaud Crassousa