MC21/COBRA-IE and VERA-CS multiphysics solutions to VERA core physics benchmark problem #6

Journal Article · 01 June 2017 · Progress in Nuclear Energy

DOI: https://doi.org/10.1016/j.pnucene.2017.05.017 · OSTI ID:1364065

Aviles, Brian N. ^[1]; Kelly, Daniel J. ^[1]; Aumiller, David L. ^[2]; Gill, Daniel F.  ^[2]; Siebert, Brett W. ^[1]; Godfrey, Andrew T. ^[3]; Collins, Benjamin S. ^[3]; Salko, Robert K. ^[3]

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1. Naval Nuclear Lab., Knolls Atomic Power Lab., Schenectady, NY (United States)
2. Naval Nuclear Lab., Bettis Atomic Power Lab., West Mifflin, PA (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

The Virtual Environment for Reactor Applications (VERA) core physics benchmark problem #6, 3D Hot Full Power (HFP) assembly, from the Consortium for Advanced Simulation of Light Water Reactors (CASL) was simulated using the MC21 continuous energy Monte Carlo code coupled with the COBRA-IE subchannel thermal-hydraulics code using the R5EXEC coupling framework. The converged MC21/COBRA-IE solution was compared to results from CASL's VERA-CS code system, MPACT coupled to COBRA-TF (CTF). MPACT is a three-dimensional (3D) whole core transport code, executed in a 2D/1D approach employing planar method of characteristics (MOC) solutions with SP₃ in the axial direction, and CTF is a subchannel thermal-hydraulics code designed for Light Water Reactor analysis. Eigenvalues agreed within 63 pcm, axially-integrated normalized radial fission distributions agreed within ±0.2% (root mean square (RMS) difference of 0.1%), local volume-averaged fuel pin temperatures agreed within +8.8/-4.3 C (RMS difference of 3.9 C), and local subchannel coolant temperatures agreed within +0.8/-1.5 C (RMS difference of 0.5 C). A sensitivity study to guide tube heat transfer indicated that a statistically-significant increase in reactivity and shift in radial pin power distribution occurred within the assembly when guide tube heating was enabled.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1364065
• Alternate ID(s): OSTI ID: 1565664
• Journal Information: Progress in Nuclear Energy, Vol. 101, Issue PC; ISSN 0149-1970
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English