Heat Transfer and Fluid Flow Characteristics of One Side Heated Vertical Rectangular Channel Inserting Copper Wire

Abstract

In the Very High Temperature Reactor (VHTR) which is a next generation nuclear reactor system, ceramics and graphite are used as a fuel coating material and a core structural material, respectively. Even if the depressurization accident occurs and the reactor power goes up instantly, the temperature of the core will change slowly. This is because the thermal capacity of the core is so large. Therefore, the VHTR system can passively remove the decay heat of the core by natural convection and radiation from the surface of the reactor pressure vessel (RPV). The objective of this study is to not only investigate heat transfer characteristics of natural convection of a one-side heated vertical channel inserting the porous materials with high porosity but also develop the passive cooling system for the Very-High-Temperature Reactor (VHTR). An experiment was carried out using the one-side heated vertical rectangular channel. In order to obtain the heat transfer and fluid flow characteristics of the vertical channel inserting porous material, we have also carried out a numerical analysis using a commercial CFD code. This paper describes thermal performances of the one-side heated vertical rectangular channel inserting copper wire with high porosity.