Iodine is one of the most hazardous fission products from radiological consequences of LWR. In this paper, the iodine source term has been evaluated for two–loop PWR under severe accident initiated due LOCA. The TMI–2 reactor is considered as the reference reactor. The modelling and simulations of release of iodine have been carried out by developing a MATLAB code that uses the post–accident conditions and core inventory as its input. The containment response, in order to mitigate the environmental and in–containment iodine source term is studied in normal, emergency, and isolation states of containment. The in–containment iodine source term has been evaluated with, and without operation of Engineering Safety features (ESFs). The environmental iodine source term is calculated as the function of containment response. The containment retention factor (CRF) for iodine has also been studied in all confined states of containment. Results indicate the weak sensitivity of iodine towards exhaust rate with ESFs operation.
Keywords: iodine source term, containment spray system, containment performance, mitigation, light water reactors, LWR accidents, nuclear reactors, nuclear energy, nuclear power, modelling, simulation, iodine release, nuclear safety, containment retention factor, hazardous products, fission products