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MELCOR Modeling of Non-LWR Systems Draft Report for the Nuclear Regulatory Commission

Beeny, Bradley A.; Humphries, Larry L.

This report provides an overview of technical issues and design features relevant to advanced reactors and reviews MELCOR's current readiness for modeling accidents in such reactor types. This report describes advanced reactor physics models currently available or under development, and gauges the level of effort required to develop new models and capabilities applicable to assessing advanced reactor safety issues. Finally, this report reviews the available database that can be used in verification and validation of new models. Four general advanced reactor types are considered in this report: 1) High Temperature Gas-Cooled Reactor (HTGR); 2) Sodium Fast Reactor (SFR); 3) Molten Salt Reactor (MSR); 4) Fluoride Salt-Cooled High Temperature Reactor (FHR)

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TYPE SAND Report YEAR 2018
DOIOSTI

Terry Turbopump Expanded Operating Band Full-Scale Integral Long-Term Low-Pressure Experiments — Preliminary Test Plan

Osborn, Douglas M.; Solom, Matthew

This document details the milestone approach to define the true operating limitations (margins) of the Terry turbopump systems used in the nuclear industry for Milestone 5 (full-scale integral long-term low-pressure operations) efforts. The overall multinational-sponsored program creates the technical basis to: (1) reduce and defer additional utility costs, (2) simplify plant operations, and (3) provide a better understanding of the true margin which could reduce overall risk of operations.

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TYPE SAND Report YEAR 2018
DOIOSTI

Thickness scaling of pyroelectric response in thin ferroelectric Hf 1-xZr xO2 films

Applied Physics Letters

Smith, Sean; Henry, David; Brumbach, Michael T.; Rodriguez, Mark A.; Ihlefeld, Jon F.

In this study, the scaling of polarization and pyroelectric response across a thickness series (5–20 nm) of Hf0.58Zr0.42O2 films with TaN electrodes was characterized. Reduction in thickness from 20 nm to 5 nm resulted in a decreased remanent polarization from 17 to 2.8 μC cm-2. Accompanying the decreased remanent polarization was an increased absolute pyroelectric coefficient, from 30 to 58 μC m-2 K-1. The pyroelectric response of the 5 nm film was unstable and decreased logarithmically with time, while that of 10 nm and thicker films was stable over a time scale of >300 h at room temperature. Finally, the sign of the pyroelectric response was irreversible with differing polarity of poling bias for the 5 nm thick film, indicating that the enhanced pyroelectric response was of electret origins, whereas the pyroelectric response in thicker films was consistent with a crystallographic origin.

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TYPE Journal Article YEAR 2018
DOIOSTI

Application Note: Mixed Signal Simulation with Xyce™

Sholander, Peter E.; Schiek, Richard

This application note describes how the Xyce circuit simulator can be coupled with external simulators via either a Python-based interface that leverages the Python ctypes foreign function library or via the Verilog Procedural Interface (VPI). It also documents the usage of these interfaces on RHEL6 and RHEL7, with Python 2.6 or 2.7. These interfaces are still under development and may change in the future. So, a key purpose of this application note is to solicit feedback on these interfaces from both internal Sandia Xyce users and other performers on the DARPA Posh Open Source Hardware (POSH) program.

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TYPE SAND Report YEAR 2018
DOIOSTI

Acoustic Chamber Characterization

Brien, Edward'; Kypta, Timothy; Stanford, Joshua; Tran, Hy

The basis of this project was to characterize the various uncertainty contributors of an acoustic chamber. The acoustic chamber will be used to calibrate and characterize infrasound sensors used in the field in the frequency range of 0.001 Hz to 4 Hz. The components characterized include the internal volume of the chamber, the piston area of the speaker creating the dynamic sound wave, the environmental stabilization of the chamber and the chamber's leak rate. Also, the resonant frequency of the chamber was evaluated and found to be far outside the frequency band of interest.

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TYPE SAND Report YEAR 2018
DOIOSTI

Transient Adjustments for Metal-Sheathed Thermocouples on Metal Plates (Shrouds)

Nakos, James T.

This report provides guidance on how to adjust temperature measurements from mineral-insulated, metal-sheathed (MIMS) thermocouples (TCs) mounted on metal plates to correct for slow transient response. This information is needed so that more accurate transient temperature measurements can be made. These more accurate temperature measurements are of benefit for both qualification of hardware and as data sets for model validation. The approach was to use a relatively simple first order adjustment to the MIMS TC reading, as compared to a more accurate metal plate temperature measurement. MIMS TCs are used to improve reliability. Results from four data sets were analyzed to determine the time constraint; an overall average of 5.0 s was obtained.

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TYPE SAND Report YEAR 2018
DOIOSTI

Advanced Tool for Computer Aided Battery Engineering (SNL)

Lamb, Joshua

This project aims to provide experimental support, including support for validation and parameterization, for mechanical failure modeling work as part of DOE's Computer Aided Engineering for Electric-Drive Vehicle Batteries (CAEBAT) program. This work involves mechanical deformation testing on both charged and discharged cells, including abusive mechanical testing leading to battery failure. The mechanical data generated is provided to the modeling teams to provide empirical parameterization as well as validation for newly developed models. Testing fully charged cells and packs (abusive battery testing) also allows for a better understanding of what conditions are most likely to lead to a potentially hazardous thermal runaway event.

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TYPE Other Report YEAR 2018
DOIOSTI

MELCOR Code Change History: Revision 9496 to 11932

Humphries, Larry L.

This document summarily provides brief descriptions of the MELCOR code enhancement made between code revision number 9496 and 11932. Revision 9496 represents the last official code release; therefore, the modeling features described within this document are provided to assist users that update to the newest official MELCOR code release, 11932. Along with the newly updated MELCOR Users' Guide and Reference Manual, users will be aware and able to assess the new capabilities for their modeling and analysis applications.

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TYPE SAND Report YEAR 2018
DOIOSTI
Results 28401–28600 of 101,000
Results 28401–28600 of 101,000
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