Numerical Analysis of the Influence on Heat Transfer Characteristics By Different  Rolling Motions Of Corium Po

Abstract

The 3D model of the corium pool was simulated and examined using the WMLES model, VOF model, phase transition model, and dynamic mesh technology. Three rolling periods (T=1.67 s, 2.50 s, and 5.00 s corresponding to 1.5, 1, and 0.5 times of the first-order intrinsic frequency, respectively) and three rolling amplitudes (A=0.035 rad, 0.070 rad, and 0.105 rad) of corium pools heat transfer were studied. The study demonstrated that the time to reach the similarly steady state heat transfer was shortened by the period corresponding to the first-order intrinsic frequency (the most violent liquid shaking), short period, and large rolling motion, and the temperature stratification characteristics were significantly weakened. The pressure vessel wall's heat transfer was accelerated by the short period, strong shaking motion, and period corresponding to the first-order intrinsic frequency.

Keywords: Serious accidents, Corium pool, Rolling motion, Heat Transfer, Forced convection