MARS-KS Code Analysis of the Pressure Wave Propagation Test 0 Performed at the PMK-2 Test Facility

Abstract

The pressure waves might be expected in the nuclear reactor systems due to sudden rupture of a pipe, quick opening or closure of a system valve. If generated, they can result in large mechanical loads on the RPV internal structures and pipelines, threating their integrity. This kind of phenomena is an important issue and a limiting accident case for the nuclear power plant safety, which requires extensive analysis to ensure the nuclear power plant safety. To study these phenomena, four PWP (Pressure Wave Propagation) tests have been performed in the PMK-2 test facility in MTA EK. In addition, these tests have been used to assess the capability of the MARS-KS code in simulating the PWP phenomena. Then, an input model representing the PMK-2 test facility was developed to simulate the tests. The MARS-KS simulation results are then compared with the test results. The comparison shows that the MARS code can well simulate the PWP frequencies and the initial pressure peaks as well. After the qualified assessment, the MARS-KS code is then deployed to conduct the sensitivity analysis on the effect of the break size, break time, coolant initial conditions on the PWP phenomena. The sensitivity analysis on the break sizes shows that the pressure wave amplitude is relevant to the break times: the shorter the break opening time is, the faster the pressure. The sensitivity analysis on the break sizes shows that the larger the break size is, the higher the pressure peak is.