Numerical Simulation Analysis of Flow and Temperature Fields in Large U-Shaped Heat Exchanger

Based on the comprehensive analysis of the complex structure and material characteristics of a large U-shaped heat exchanger, combined with the thin-shell heat transfer model and the similarity principle, the 3D geometric model of the heat exchanger of the original stabilizing device is constructed. Then, the grid size is greatly reduced by using boundary layer meshing technology. Finally, the temperature field and flow field distribution of the fluid in the heat exchanger are obtained by finite element calculation. The results show that, on the one hand, the condensate temperature is in a local overheating state and the oil flow rate is too low, and there is a retention zone; on the other hand, the temperature in the overheating region decreases with the increase of the shell flow rate. Therefore, the coupling effect of condensate oil retention and local overheating may accelerate the corrosion rate of heat exchanger tube bundle. It is suggested to adjust the operation parameters of the heat exchanger and optimize the internal structure to make the internal flow rate and temperature distribution more reasonable, so as to improve the service safety and reliability of the heat exchanger.