Study on Natural Circulation and Its Transition Process for IP200

摘要

In the paper, Relap5/MOD4.0 codes are applied to simulate the transition process from forced circulation to natural circulation for IP-200. Furthermore, analysis on key factors that influenced the process is presented. 1. Reactor power influences the transition progress directly. The higher power level will result in less safety margin. 2. To improve natural circulation capability, we should select MCP with less resistance or set a bypass loop for MCP. 3. With greater rotational inertia of MCP, it is easier to build up steady natural circulation.