A Non-Heating Small-Sclaed Experimental Study on the Two-Phase Natural Circulation Flow through an Annular Gap between Reactor Vessel and Insulation

소형 비가열 실험을 이용한 원자로용기 외벽냉각시 용기와 단열재 사이의 자연순환 이상유동에 관한 연구

A 1/21.6 scaled non-heating experimental facility was prepared utilizing the results of a scaling analysis to simulate the APR1400 reactor and insulation system. The behaviors of the air bubble-induced two-phase natural circulation flow in the insulation gap were observed, and the liquid mass flow rates driven by natural circulation loop were measured by varying the injected air flow rate and distribution. As the injected air flow rates increased, the natural circulation flow rates also increased. Both the longitudinal and the latitudinal distributions of the injected air affected the natural circulation flow rates, especially, the longitudinal effect is more larger.