PASSIVE DECAY HEAT REMOVAL AND INTERNAL DEPRESSURIZATION SYSTEM FOR NUCLEAR REACTORS

摘要

A jet condenser (30) injects steam from a steam generator (10) into a mixing tube (50), where it combines with coolant water from a heat exchanger (32). The steam completely condenses upon mixing with the water because the ratio of the mass flow rate of water to that of steam is relatively high at any given combination of temperatures and pressures. The mixture of coolant water and condensate then enters a divergent tube (52). This action enhances dynamic natural convection in the condenser loop (39), which provides the forces that move the water through the loop (39). A small portion of the water is returned to the steam generator (10); the remainder is diverted to the heat exchanger (32). The mass flow of the steam in the jet condenser (30) is equal to that of the condensate returned to the steam generator (10), thereby maintaining a constant coolant water inventory. During an accident, radioactive fission products would be retained within the closed jet condenser loop (39).