MPACT Theory Manual, Version 2.2.0

Technical Report · Thu Jun 09 04:00:00 EDT 2016

DOI:https://doi.org/10.2172/1340449· OSTI ID:1340449

Downar, Thomas ^[1]; Collins, Benjamin S. ^[2]; Gehin, Jess C. ^[2]; Godfrey, Andrew T. ^[2]; Jabaay, Daniel ^[1]; Kelley, Blake W. ^[1]; Clarno, Kevin T. ^[2]; Kim, Kang ^[2]; Kochunas, Brendan ^[1]; Larsen, Edward W. ^[1]; Liu, Yuxuan ^[1]; Liu, Zhouyu ^[1]; Martin, William R. ^[1]; Palmtag, Scott ^[3]; Rose, Michael ^[1]; Saller, Thomas ^[1]; Stimpson, Shane ^[1]; Trahan, Travis ^[1]; Wang, J. W. ^[1]; Wieselquist, William A. ^[2] ; Young, Mitchell ^[1]; Zhu, Ang ^[1]

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1. Univ. of Michigan, Ann Arbor, MI (United States)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. Core Physics, Inc., Cary, NC (United States)

This theory manual describes the three-dimensional (3-D) whole-core, pin-resolved transport calculation methodology employed in the MPACT code. To provide sub-pin level power distributions with sufficient accuracy, MPACT employs the method of characteristics (MOC) solutions in the framework of a 3-D coarse mesh finite difference (CMFD) formulation. MPACT provides a 3D MOC solution, but also a 2D/1D solution in which the 2D planar solution is provided by MOC and the axial coupling is resolved by one-dimensional (1-D) lower order (diffusion or P3) solutions. In Chapter 2 of the manual, the MOC methodology is described for calculating the regional angular and scalar fluxes from the Boltzmann transport equation. In Chapter 3, the 2D/1D methodology is described, together with the description of the CMFD iteration process involving dynamic homogenization and solution of the multigroup CMFD linear system. A description of the MPACT depletion algorithm is given in Chapter 4, followed by a discussion of the subgroup and ESSM resonance processing methods in Chapter 5. The final Chapter 6 describes a simplified thermal hydraulics model in MPACT.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Consortium for Advanced Simulation of LWRs (CASL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1340449
• Report Number(s): ORNL/TM--2016/476; CASL-U-2016-1107-000
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
97 MATHEMATICS AND COMPUTING
ACCURACY
ALGORITHMS
BOLTZMANN EQUATION
FINITE DIFFERENCE METHOD
M CODES
MANUALS
MATHEMATICAL SOLUTIONS
ONE-DIMENSIONAL CALCULATIONS
POWER DISTRIBUTION
REACTOR CORES
RESONANCE
SCALARS
THERMAL HYDRAULICS
THREE-DIMENSIONAL CALCULATIONS
TRANSPORT THEORY
TWO-DIMENSIONAL CALCULATIONS