To improve the thermal efficiency of intermediate heat exchanger (IHX) in high temperature gas-cooled reactor, the influence of artificial roughness on heat transfer enhancement is simulated by CFD software. From the aspects of flow distribution, axial velocity, transverse velocity, turbulence kinetic energy, temperature field and wall heat transfer coefficient, we made a preliminary research comparing the smooth tube and rough tube. The results showed that artificial roughness would destroy the adhesive layer of turbulent boundary layer, and the roughness would enhance lateral disturbance. Though the efficiency of heat convection was improved, the frictional resistance was also increased because the decrease of axial velocity. As a result, the research can provide necessary theoretical support to design a rough tube having the best heat transfer efficiency.
