Analysis for Performance of Passive Heat Removal by a Water Cooling Panel from a High-Temperature Gas-Cooled Reactor

Abstract

An experiment was performed to simulate a water cooling panel system for passive decay heat removal from, a high-temperature gas-cooled reactor, comprised of a pressure vessel topped by a complex three-dimensional structure of stand pipes, to investigate the performance of decay heat removal and the temperature distributions of system components. The experimental apparatus consists of a pressure vessel of 1 m in diameter and 3 m in height, bristling with nineteen stand pipes atop and containing internal heaters with a maximum heating rate of 100 kW to simulate the decay heat of the core. The pressure vessel is surrounded by the water cooling panels. The analytical code THANPACST2 was applied to validate its analytical methods and a newly-proposed axi-symmetrical model simulating the stand pipes by porous body cells against the experimental data. Under the conditions of helium gas at pressure of 0.47 MPa and temperatures up to 430°C in the pressure vessel, the temperatures of the critical spots, where peak temperatures appeared near the top of the pressure vessel, were estimated within difference between -25 and +70°C from the experimental data. The heat transferred to the cooling panel was estimated to be 4.1% less than the experimental value.