skip to main content

SciTech ConnectSciTech Connect

Title: Verification & Validation of High-Order Short-Characteristics-Based Deterministic Transport Methodology on Unstructured Grids

The research team has developed a practical, high-order, discrete-ordinates, short characteristics neutron transport code for three-dimensional configurations represented on unstructured tetrahedral grids that can be used for realistic reactor physics applications at both the assembly and core levels. This project will perform a comprehensive verification and validation of this new computational tool against both a continuous-energy Monte Carlo simulation (e.g. MCNP) and experimentally measured data, an essential prerequisite for its deployment in reactor core modeling. Verification is divided into three phases. The team will first conduct spatial mesh and expansion order refinement studies to monitor convergence of the numerical solution to reference solutions. This is quantified by convergence rates that are based on integral error norms computed from the cell-by-cell difference between the code’s numerical solution and its reference counterpart. The latter is either analytic or very fine- mesh numerical solutions from independent computational tools. For the second phase, the team will create a suite of code-independent benchmark configurations to enable testing the theoretical order of accuracy of any particular discretization of the discrete ordinates approximation of the transport equation. For each tested case (i.e. mesh and spatial approximation order), researchers will execute the code and compare the resulting numericalmore » solution to the exact solution on a per cell basis to determine the distribution of the numerical error. The final activity comprises a comparison to continuous-energy Monte Carlo solutions for zero-power critical configuration measurements at Idaho National Laboratory’s Advanced Test Reactor (ATR). Results of this comparison will allow the investigators to distinguish between modeling errors and the above-listed discretization errors introduced by the deterministic method, and to separate the sources of uncertainty.« less
Authors:
 [1] ;  [1]
  1. North Carolina State Univ., Raleigh, NC (United States)
Publication Date:
OSTI Identifier:
1111549
Report Number(s):
DOE/NEUP--09-798
TRN: US1600168
DOE Contract Number:
AC07-05ID14517
Resource Type:
Technical Report
Research Org:
North Carolina State Univ., Raleigh, NC (United States); Idaho National Lab. (INL), Idaho Falls, ID (United States)
Sponsoring Org:
USDOE, Nuclear Energy University Programs (NEUP)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 22 GENERAL STUDIES OF NUCLEAR REACTORS; NUMERICAL SOLUTION; VALIDATION; NEUTRON TRANSPORT THEORY; COMPARATIVE EVALUATIONS; ATR REACTOR; DISCRETE ORDINATE METHOD; MONTE CARLO METHOD; COMPUTERIZED SIMULATION; EXACT SOLUTIONS; ERRORS; VERIFICATION; THREE-DIMENSIONAL LATTICES; REACTOR CORES; CONVERGENCE; THREE-DIMENSIONAL CALCULATIONS; ACCURACY; COORDINATES; BENCHMARKS; DISTRIBUTION; SERIES EXPANSION; ZERO POWER REACTORS