Theoretical Study on Density Wave Oscillation of Two-Phase Natural Circulation under Low Quality Conditions

A theoretical study of the Density Wave Oscillation (DWO) of a natural circulation loop is presented in this paper. The nonlinear analysis based on the drift flux model is performed. The momentum equation is integrated around a closed loop, and the energy equation is integrated separately for every component. The equations are solved numerically using the Gear method, suitable for solving nonlinear stiff equations, with a newly developed Nonlinear Time Domain Computer Code (NTDCC). The Marginal Stability Boundary (MSB) of DWO of the low Temperature Heating Reactor (THR) designed in China was obtained by NTDCC. The results obtained by NTDCC are in good agreement with the experimental results.