ICONE23-1865 NUMERICAL SIMULATION OF HOT GAS MIXING WITH LEAKAGE FLOW AT HTR-PM REACTOR CORE OUTLET

Abstract

The numerical simulation for the design of hot gas mixing structure at the reactor outlet of Pebble-bed Module High Temperature gas-cooled Reactor (HTR-PM) are carried out by using the Fluent code with the consideration of the leakage flow out of the reactor core. According to the profiles of temperature, pressure and velocity, the thermal mixing is mainly produced by the secondary flow such as the vortices which is perpendicular or parallel to the main flow direction. In addition, the pressure drop is mainly caused by the local pressure loss leading by the sudden change of flow area and direction which is also the main reason of production of the secondary flow. The numerical simulation results indicate that the design of hot gas mixing structure at HTR-PM reactor outlet can fulfill the requirement of high thermal mixing performance and low pressure drop under the rated condition by taking account into the leakage flow out of reactor.