Experimental study on aerosol collection by spray droplets; Application to fission products removal in containment

スプレイ液滴によるエアロゾル除去に関する実験的研究; 格納容器内放射性物質除染への適用

孫 昊旻   ; Leblois, Y.*; Gelain, T.*; Porcheron, E.*

Sun, Haomin; Leblois, Y.*; Gelain, T.*; Porcheron, E.*

During a severe accident of PWR, fission products (FPs) may be released. Containment spray can be utilized to remove the aerosols of FPs. Therefore, it is important to develop an analytical model for predicting aerosol removal efficiency. The containment spray has high spray coverage ratio where the droplets are expected to impact side walls. In such condition, the gas flow induced by droplets will behave differently from that without droplet impaction where a stable gas circulation is expected. Since the aerosol removal efficiency depends on gas flow, to develop the removal model for the containment spray from this viewpoint, several experiments were carried out in TOSQAN facility. It was confirmed that the spray coverage ratios were comparable to that of the containment spray and many droplets impacted side wall. Aerosol removal was found to be more effective in higher spray water flow rates. Aerosol concentration decay calculated by CFD was in agreement with measured one.