Analysis of Heat Exchange Performance of Heat Exchange Tubes of Evaporative Heat Exchanger Based on Fluent

In order to study the influence of the heat exchange tubes length of the evaporative heat exchanger on the heat exchange performance of the organic Rankine cycle technology (ORC) in automobile exhaust heat recovery, four kinds of three-layer tube heat exchange tube models with the length of 500mm, 800mm, 1100mm and 1400mm are designed by DM modeling software, and they are simplified into a quarter calculation domain model. The simulation calculations of the coupling heat exchange of four different lengths of heat exchange tubes are performed by using the Couple algorithm of Fluent fluid simulation software and the κ-ε model. Through the simulation calculation of the heat exchange of the four three-layer heat exchange tubes, it can be seen that the temperature in the three-layer heat exchange tubes changes along the Z axis direction. The heat exchange performance of different lengths of heat exchange tubes can be obtained by analyzing the temperature cloud diagrams of the XY plane at both ends of the heat exchange tubes and the temperature change curve along the Z axis direction. The heat exchange simulation analysis results of the four three-layer heat exchange tubes show that under the set parameter model, only the inlet and outlet boundary temperature is considered, and the three-layer heat exchange tube with a length of 1400mm has better heat exchange performance.