Flow and heat transfer characteristics of the helium-xenon mixture under flow blockage

Abstract

To examine the effect of the helium-xenon mixture ratio on the flow and heat transfer characteristics of the reactor channel under the blockage condition, a numerical simulation is performed for a single channel under different blockage rates and helium-xenon mixture ratios. In this study, commercial software for numerical calculations was used to establish different blockage models and calculate the flow and heat transfer characteristics of channels with different helium-xenon mixing ratios. The results show that, in terms of heat transfer characteristics, a channel blockage will form an obvious vortex structure and boundary layer separation in the blocked area, leading to a high local temperature on the wall, whereas the blockage rate has little effect on the convective heat transfer coefficient of the channel. In terms of flow characteristics, the pressure drop and friction coefficient increase with the increase in the blockage ratio, and the trend is the same with the increase in the helium-xenon mixture ratio. The comprehensive performance coefficient decreases with the mixing ratio of helium and xenon. Moreover, the larger the blockage ratio, the smaller the comprehensive performance coefficient; the greater the blockage ratio, the more obvious the influence on the flow and heat transfer characteristics of the channel.