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Martineau, R. C.

Publications and source records attributed to Martineau, R. C..

8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Coupled Monte Carlo and thermal-fluid modeling of high temperature gas reactors using Cardinal

Cardinal is an open-source application that couples OpenMC Monte Carlo transport and NekRS computa-tional fluid dynamics to the Multiphysics Object-Oriented Simulation Environment (MOOSE), closing neutronics and thermal-fluid gaps in conducting high-resolution multiscale and multiphysics analyses of nuclear systems. Here, we provide an introduction to Cardinal's software design, data mapping, and multi -physics coupling strategy to highlight our approach to overcoming common challenges in multiphysics simulation. We then describe an application of Cardinal to prismatic High Temperature Gas Reactors (HTGRs) with various combinations of NekRS, OpenMC, BISON, and THM. A high-resolution coupling of NekRS, OpenMC, and BISON provides a reference solution at the unit cell level and shows excellent agree-ment with a lower-resolution coupling of THM, OpenMC, and BISON. A full core coupling of THM, OpenMC, and BISON resolving the three-dimensional conjugate heat transfer and sub-pin power distri-bution then provides detailed predictions of HTGR temperatures and the fission distribution.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2019

YRA poster session - July 25 2019

The poster presents the results of the current research activities I am carrying on for the verification and validation of the MOOSE based code Pronghorn.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2018

RELAP-7 Theory Manual

This document summarizes the physical models and mathematical formulations used in the RELAP-7 code.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Validation of PRONGHORN with the SANA Experiments

In this work, we have re-established the pronghorn’s capability to simulate heat and mass transfer in pebble beds based on porous medium assumption. Although more sophisticated physics models are available, we have limited ourselves to use the simpler Darcy flow model inherited from older versions of this code. Closure correlation, such as friction coefficients in pebble beds and fluid-to-pebble heat transfer coefficients, are reviewed, selected, and implemented in pronghorn code to support simulations of interest to nuclear reactor thermal hydraulics analysis. Numerical verification was performed in form of mesh convergence study using Method of Manufactured Solutions (MMS). For both spatial and temporal integration schemes, expected order of convergence were observed. Validation of this code was performed by comparing simulation results against experimental measurements of the SANA experiment. For helium cases at three power levels, simulations results of pebble temperatures agree with experiment measurements reasonably well. For nitrogen cases, because less accurate thermal-dynamics properties were used, relatively larger discrepancies between simulation results and experiment measurements were found. However, we anticipate that this will be improved when a more accurate nitrogen gas thermal-dynamics properties package is available.

42 ENGINEERING↗
DOE OSTI2017

Application of the new IAPWS Guideline on the fast and accurate calculation of steam and water properties with the Spline-Based Table Look-Up Method (SBTL) in RELAP-7

The numerical simulation of thermalhydraulic processes in nuclear power plants requires very accurate and extremely fast algorithms for calculating the thermophysical properties of water and steam. In order to provide such algorithms, the International Association for the Properties of Water and Steam (IAPWS) has adopted the new “IAPWS Guideline on the Fast Calculation of Steam and Water Properties with the Spline-Based Table Look-Up Method (SBTL)”. In this article, the SBTL method is applied to property functions of specific volume and specific internal energy (v,e) based on the scientific formulation IAPWS-95 and the latest IAPWS formulations for transport properties. From the newly generated SBTL functions, thermodynamic and transport properties as well as their derivatives and inverse functions are calculable in the fluid range of state for pressures up to 100 MPa and for temperatures up to 1273 K, including the metastable liquid and the metastable vapor regions. The SBTL functions reproduce the underlying formulations with an accuracy of 10–100 ppm and significantly reduced computing times. The SBTL method has been implemented into the nuclear reactor system safety analysis code RELAP-7 [2] to consider the real fluid behavior of water and steam in a novel 7-equation two-phase flow model.

42 ENGINEERING↗
DOE OSTI2017

RELAP-7 Closure Correlations

The RELAP-7 code is the next generation nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). The code is based on the INL’s modern scientific software development framework, MOOSE (Multi-Physics Object Oriented Simulation Environment). The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical integration methods, and physical models. The end result will be a reactor systems analysis capability that retains and improves upon RELAP5’s and TRACE’s capabilities and extends their analysis capabilities for all reactor system simulation scenarios. The RELAP-7 code utilizes the well-posed 7-equation two-phase flow model for compressible two-phase flow. Closure models used in the TRACE code has been reviewed and selected to reflect the progress made during the past decades and provide a basis for the colure correlations implemented in the RELAP-7 code. This document provides a summary on the closure correlations that are currently implemented in the RELAP-7 code. The closure correlations include sub-grid models that describe interactions between the fluids and the flow channel, and interactions between the two phases.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗