COMMIX-1: A Three-Dimensional Transient Single-Phase Component Computer Program for Thermal-Hydraulic Analysis,

摘要

This report develops and presents a mathematical model and a numerical-solution technique -- COMMIX-1Computer Program --for three-dimensional,transient,single-phase,thermal-hydraulic analysis of reactor components. A set of governing equations for the conservation of mass,momentum,and energy is solved as a boundary-value problem in space and as an initial-value problem in time. The model can treat both continuum (e.g.,reactor plenum) and quasi-continuum (e.g.,rod bundles or fuel assembly) sodium systems. Volume porosity,surface permeability,and distributed resistance are used in the quasi-continuum approach,which alleviates two inherent deficiencies associated with conventional subchannel analysis;one is the approximation used in the formulation of transverse momentum equations,the other is its inability to handling reverse flow or recirculatory flow.