Code Verification and Solution Verification framework in pin-resolved neutron transport code MPACT

Journal Article · Fri Aug 19 00:00:00 EDT 2022 · Annals of Nuclear Energy

DOI:https://doi.org/10.1016/j.anucene.2022.109365· OSTI ID:1885381

Wang, Jipu ^[1]; Martin, William R. ^[2]; Downar, Thomas J. ^[2]; Kochunas, Brendan ^[2]; Andrews, Nathan C. ^[3]; Gilkey, Lindsay ^[3]; Walker, Erik D. ^[4]; Collins, Benjamin S. ^[4]; Pilch, Martin ^[5]

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1. Shenzhen Univ. (China)
2. Univ. of Michigan, Ann Arbor, MI (United States)
3. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
5. MPilch Consulting, Tijeras, NM (United States)

Program verification in scientific computing encompasses the application of formal and mathematical techniques to a scientific computing code for its credibility, accuracy, and validity. Code Verification identifies bugs and performance issues in the software development stage. Solution Verification assesses the applicability of the code and the accuracy of the solution to problems of interest. Both activities utilize application cases and quantify the error against prescribed acceptance criteria. However, simply executing more application cases does not guarantee stronger or more comprehensive credibility. Here, we establish a verification framework that involves Code Verification and Solution Verification, both of which work together such that the overarching goal of “converge to the correct answer for the intended application” can be reasonably inferred. The application of such a verification framework is demonstrated using the pin-resolved neutron transport code MPACT, where standard unit tests and regression tests are covered, and where the Method of Exact Solutions and the Method of Manufactured Solutions are successfully used. Additionally, the applicability of Method of Manufactured Solutions is extended to the OECD/NEA C5G7 benchmark problems of practical material and geometric configurations. Solution Verification activities are demonstrated on a practical hierarchy of application models of increasing complexity ranging from 2D pin cell problems to 3D assembly problems. The convergence behavior and rate of convergence with respect to each individual variable are studied and provided. This framework can be adapted broadly to other fields involving scientific computing codes.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: Consortium for Advanced Simulation of Light Water Reactors; USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC05-00OR22725; NA0003525
• OSTI ID: 1885381
• Journal Information: Annals of Nuclear Energy, Journal Name: Annals of Nuclear Energy Journal Issue: 1 Vol. 178; ISSN 0306-4549
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

97 MATHEMATICS AND COMPUTING
code verification
convergence
method of manufactured solutions
solution verification
verification