Authors: P.F. Niemand, C.G. Du Toit
Year: 2018
Industry: Nuclear & SMR
Keywords: Use FSE, RCCS, Comparison, Verification
ABSTRACT
The reactor cavity cooling system (RCCS) is a safety related system to be employed in the fourth generation nuclear reactor designs. The system is intended to remove decay heat from the reactor cavity in a passive manner, especially, under upset conditions. The NACEF (natural cooling experimental facility) was constructed to represent a ¼ scale model of the RCCS to be used in the PMR200 nuclear reactor. The codes GAMMA+ and Flownex were used to simulate the NACEF in a verification exercise. The same boundary conditions were used in both codes and the results were compared. The fluid temperatures and the convection heat transfer coefficients were used as a measure of the agreement between the results as produced by using the two codes. The results obtained by using the two simulation codes show very good agreement. The mixed convection flow regime in the riser tubes resulted in a deterioration in the heat transfer under some of the conditions.