Turbulent Flow Boundary Layer and Heat Transfer Characteristics for the Intermediate Heat-Exchanger Simulation of a VHTR

In order to improve the thermal efficiency of the intermediate heat exchanger (IHX) in high temperature gas-cooled reactor, the article takes a theoretical calculation and simulation analysis of different turbulence models on the turbulent flow boundary layer of the IHX. And a suitable model for the high temperature and high pressure unit of the IHX is built. According to the boundary layer distribution of different models and the fluid velocity and temperature changes of central region, we find the related characteristics and cut-off point of the boundary layer area and the Poiseuille flow area. At the same time, the paper verifies the three kinds of turbulence model and the formula with solution theory, including the relationship of Nu (Nusselt) number and Re (Reynolds) number and the partial wall friction resistance. These results provides theoretical support for the next step of the heat transfer enhancement research using the artificial roughness elements.