Study of a multi-factor coupling removal model for gas-borne source terms under jet flow conditions

After a pipe rupture in the reactor steam generator, high-temperature and high-pressure radioactive materials from the primary circuit enter the secondary side of the steam generator via a jet flow. During this process, the physical properties of the water in the liquid pool change as the washing progresses, which in turn affects the removal of radioactive materials. To investigate the multi-factor coupling removal characteristics of aerosols under jet flow conditions, a study was conducted on a jet flow aerosol washing removal model. By integrating a thermal-hydraulic model, an analysis program suitable for jet flow conditions was developed and validated. The validation process demonstrated that the developed model can accurately predict the jet flow washing process of aerosols. The study using this model revealed that as the submergence depth increases, the DF in the rising zone gradually increases, while the DF in the injection zone gradually decreases. Even at higher submergence depths, the jet flow aerosol removal in the injection zone continues to make a significant contribution to the overall washing process. Under the same submergence depth conditions, as the mass flux increases, the contribution of the DF in the injection zone becomes more pronounced, significantly influencing the jet flow aerosol removal mechanism during the washing process. When comparing the results of the developed jet flow washing removal model with those of existing international aerosol washing analysis programs, it was found that the developed model provides more accurate overall predictions of the DF for aerosol washing.