CFD simulation of hydrodynamics and scrubbing behaviour of iodine vapors in a self-priming venturi scrubber

In a severe accident scenario, the inadequate heat removal in a nuclear reactor can lead to over pressurization of the containment thus challenging its integrity. If not controlled, this can lead to release of radionuclides and high pressure steam in the environment. To ensure that the containment building remains intact and the reactor depressurizes, the vent line from the reactor is directed to a scrubber tank consisting of multiple venturi scrubbers, metal fiber filter and demister pad (known as Filtered Containment Venting System (FCVS)). This is a passive safety measure suggested for installation in advanced and existing nuclear reactors post Fukushima event. The venturi scrubber plays an important role in depressurizing the containment and filtering the contaminated gas. A numerical model is developed and validated with experimental results to understand the hydrodynamics and scrubbing of iodine vapors in such passive mode of operation. (author)