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Verification and Validation Propensity Improvements via Solution Verification Automation: Presentation Package (Part 1 of 2) (FY15 ASC L2 milestone #5320)

Staten, Matthew L.; Carnes, Brian R.; Cox, James V.

A new tool, called Mesh Scaling, for producing series of hexahedral meshes suitable for solution verification was enhanced and hardened by this milestone. In addition, solution verification using the meshes produced from Mesh Scaling was performed and documented. We conclude that Mesh Scaling now produces meshes suitable for solution verification, while offering a substantial decrease in the computational cost of solution verification.

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TYPE Other Report YEAR 2015
DOIOSTI

Evaluating the Material Point Method in CTH Using the Method of Manufactured Solutions

Ruggirello, Kevin P.; Nishawala, Vinesh V.

The Method of Manufactured Solutions (MMS) is used to evaluate the Material Point Method (MPM) implemented in CTH, i.e. Markers. MMS is a verification approach in which a desired deformation field is prescribed and the required forcing function to achieve the prescribed deformation is determined analytically. The calculated forcing function is applied within CTH markers determine if the correct displacement field is recovered. For the cases examined in this study, a ring is subjected to a finite, angular-independent, spatially varying body force, superposed with a rigid-body rotation. This test will assess the solid mechanics response of the MPM within CTH for large deformation problems. This page intentionally left blank.

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TYPE SAND Report YEAR 2015
DOIOSTI

Alternatives to the 15% Rule: Modeling and Hosting Capacity Analysis of 16 Feeders

Smith, Jeff; Rylander, Matthew; Reno, Matthew J.; Broderick, Robert J.; Mather, Barry; Quiroz, Jimmy E.; Munoz-Ramos, Karina

This project is part of the third solicitation of the California Solar Initiative (CSI3) Research, Development, Demonstration, and Deployment Program created by the California Public Utilities Commission (CPUC) in 2006 to support solar research in California. The program focuses on research to improve the utility application review and approval process for interconnecting distributed energy resources such as solar to the distribution system. The CSI3 program is supporting EPRI, National Renewable Energy Laboratory (NREL), and Sandia National Laboratories (SNL) in their collaboration on the process with Pacific Gas and Electric (PG&E), Southern California Edison (SCE), and San Diego Gas and Electric (SDG&E). At present, the application review and approval process is the most time-consuming of any step on the path to generating power for delivery through the distribution system.

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TYPE Other Report YEAR 2015
DOIOSTI

V&V Framework

Hills, Richard G.; Maniaci, David C.; Naughton, Jonathan W.

A Verification and Validation (V&V) framework is presented for the development and execution of coordinated modeling and experimental program s to assess the predictive capability of computational models of complex systems through focused, well structured, and formal processes. The elements of the framework are based on established V&V methodology developed by various organizations including the Department of Energy, National Aeronautics and Space Administration, the American Institute of Aeronautics and Astronautics, and the American Society of Mechanical Engineers. Four main topics are addressed: 1) Program planning based on expert elicitation of the modeling physics requirements, 2) experimental design for model assessment, 3) uncertainty quantification for experimental observations and computational model simulations, and 4) assessment of the model predictive capability. The audience for this document includes program planners, modelers, experimentalist, V &V specialist, and customers of the modeling results.

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TYPE SAND Report YEAR 2015
DOIOSTI

Novel Metal-Organic Frameworks for Efficient Stationary Sources via Oxyfuel Combustion

Nenoff, Tina M.; Gallis, Dorina F.S.; Parkes, Marie V.; Greathouse, Jeffery A.; Rodriguez, Mark A.; Paap, Scott M.; Williams, Timothy C.; Shaddix, Christopher R.

Oxy-fuel combustion is a well-known approach to improve the heat transfer associated with stationary energy processes. Its overall penetration into industrial and power markets is constrained by the high cost of existing air separation technologies for generating oxygen. Cryogenic air separation is the most widely used technology for generating oxygen but is complex and expensive. Pressure swing adsorption is a competing technology that uses activated carbon, zeolites and polymer membranes for gas separations. However, it is expensive and limited to moderate purity O2 . MOFs are cutting edge materials for gas separations at ambient pressure and room temperature, potentially revolutionizing the PSA process and providing dramatic process efficiency improvements through oxy-fuel combustion. This LDRD combined (1) MOF synthesis, (2) gas sorption testing, (3) MD simulations and crystallography of gas siting in pores for structure-property relationship, (4) combustion testing and (5) technoeconomic analysis to aid in real-world implementation.

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TYPE SAND Report YEAR 2015
DOIOSTI

Construction of Hexahedral Elements Mesh Capturing Realistic Geometries of Bayou Choctaw SPR Site

Park, Byoung; Roberts, Barry L.

The three-dimensional finite element mesh capturing realistic geometries of Bayou Choctaw site has been constructed using the sonar and seismic survey data obtained from the field. The mesh is consisting of hexahedral elements because the salt constitutive model is coded using hexahedral elements. Various ideas and techniques to construct finite element mesh capturing artificially and naturally formed geometries are provided. The techniques to reduce the number of elements as much as possible to save on computer run time with maintaining the computational accuracy is also introduced. The steps and methodologies could be applied to construct the meshes of Big Hill, Bryan Mound, and West Hackberry strategic petroleum reserve sites. The methodology could be applied to the complicated shape masses for not only various civil and geological structures but also biological applications such as artificial limbs.

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TYPE SAND Report YEAR 2015
DOIOSTI

Threaded Operations on Sparse Matrices

Sneed, Brett

We investigate the use of sparse matrices and OpenMP multi-threading on linear algebra operations involving them. Several sparse matrix data structures are presented. Implementation of the multi- threading primarily occurs in the level one and two BLAS functions used within the four algorithms investigated{the Power Method, Conjugate Gradient, Biconjugate Gradient, and Jacobi's Method. The bene ts of launching threads once per high level algorithm are explored.

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TYPE Thesis or Dissertation YEAR 2015
OSTI

Distribution System Secondary Circuit Parameter Estimation for Model Calibration

Peppanen, Jouni; Reno, Matthew J.; Broderick, Robert J.; Grijalva, Santiago

To analyze and coordinate the operation of distribution systems with rapidly increasing amounts of PV, more accurate distribution system models are required, especially for the distribution system secondary (low-voltage) circuits down to the point of common coupling for distributed PV. There is a growing need for automated procedures to calibrate the distribution system secondary circuit models that are typically either not modeled at all or are modeled with a lower level of detail than the better modeled medium-voltage systems. This report presents an accurate, flexible, and computationally efficient method to use measurement data to estimate secondary circuit series impedance parameters in existing utility feeder models. The parameter estimation method assumes well-modeled primary circuit models, known secondary circuit topologies, and AMI active power, and reactive power measurements at all the loads in the secondary circuit. The method also requires AMI voltage measurement at most of the loads in the secondary circuit but can handle loads that do not have voltage measurements. No existing secondary circuit model information is needed, except for topology. The method is based on the well-known linearized voltage drop approximation and linear regression. The performance of the method is demonstrated on a three-phase test circuit with ten different secondary circuit topologies and on the Georgia Tech campus distribution system with AMI data. The developed method can be utilized to improve existing utility feeder models for more accurate analysis and operation with ubiquitous distributed PV interconnected on the low-voltage circuits.

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TYPE SAND Report YEAR 2015
DOIOSTI

Design of the Cryogenic Hydrogen Release Laboratory

Hecht, Ethan S.; Zimmerman, Mark D.; Lafleur, Angela (Chris); Ciotti, Michael

A cooperative research and development agreement was made between Linde, LLC and Sandia to develop a plan for modifying the Turbulent Combustion Laboratory (TCL) with the necessary infrastructure to produce a cold (near liquid temperature) hydrogen jet. A three-stage heat exchanger will be used to cool gaseous hydrogen using liquid nitrogen, gaseous helium, and liquid helium. A cryogenic line from the heat exchanger into the lab will allow high-fidelity diagnostics already in place in the lab to be applied to cold hydrogen jets. Data from these experiments will be used to develop and validate models that inform codes and standards which specify protection criteria for unintended releases from liquid hydrogen storage, transport, and delivery infrastructure.

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TYPE SAND Report YEAR 2015
DOIOSTI

New Radiological Material Detection Technologies for Nuclear Forensics: Remote Optical Imaging and Graphene-Based Sensors

Harrison, R.K.; Martin, Jeffrey B.; Wiemann, Dora K.; Choi, Junoh; Howell, Stephen W.

We developed new detector technologies to identify the presence of radioactive materials for nuclear forensics applications. First, we investigated an optical radiation detection technique based on imaging nitrogen fluorescence excited by ionizing radiation. We demonstrated optical detection in air under indoor and outdoor conditions for alpha particles and gamma radiation at distances up to 75 meters. We also contributed to the development of next generation systems and concepts that could enable remote detection at distances greater than 1 km, and originated a concept that could enable daytime operation of the technique. A second area of research was the development of room-temperature graphene-based sensors for radiation detection and measurement. In this project, we observed tunable optical and charged particle detection, and developed improved devices. With further development, the advancements described in this report could enable new capabilities for nuclear forensics applications.

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TYPE SAND Report YEAR 2015
DOIOSTI
Results 46001–46100 of 99,299
Results 46001–46100 of 99,299