Study on Fluid-solid Coupling Heat Transfer Characteristics of TWR Assembly with 19 Fuel Pins Based on CFD Method

Characteristics of flow and heat transfer of TWR assembly with 19 fuel pins were studied by fluid-solid coupling heat transfer method. The results show that there is obviously asymmetrical and eccentric temperature distribution characteristic in outlet area. The temperature difference of coolant is quite obvious in downstream cross section. Huge heat flux difference appears on the cladding surface. The helix wrapped wire shows the ability of heat transfer enhancing. The inverse heat transfer phenomena are caught in outlet area. The structures of bundles need to be improved by fluid-solid coupling heat transfer calculation in the future.