The Finite Element Analysis Of7.53×10~6kJ/h Tube Type Heat Exchanger

Heat exchanger is an equipment used for passing heat between two kinds of liquid which have different temperature. In industrial production, heat exchanger’s primary application is passing heat from high temperature liquid to low temperature liquid, and makes the liquid’s temperature meet technology requirement.The strength analysis for heat exchanger mostly focused on using experience value or technical parameters as boundary conditions. But it may have a quite difference with the actual condition, and the analysis results may also have a big error.This thesis uses CFD software FLUENT to simulate the movement and heat transfer of the heat exchanger and get the temperature distribution. Then the thesis uses the result as loads for structural analysis. So the analysis precision can be improved.This thesis simulates the movement and heat transfer of the heat exchanger in steady work state, and compares the twisted-model’s heat transfer performance with the no-twisted-model’s. It points out that the heat exchanger’s design parameter has deficiency, and suggests that the heat exchanger can be improved by reducing the velocity of air or by using short twisted tape instead of long twisted tape.The effect of the velocity of air to the twisted-tube’s or no-twisted-tube’s surface heat transfer coefficient is analysed through the simulation to the single tube model. This thesis compares the difference between twisted-tube’s and no-twisted-tube’s heat transfer performance and points out that the velocity of air in the tube should be controlled below20m/s.This thesis reconstructs the temperature field of the heat exchanger in the structural analysis, and analyses the temperature distribution of the heat exchanger from the angle of surface heat transfer coefficient. It analyses the stress and deformation of the heat exchanger under gravity alone and under thermal loads alone and the couple of them. And concludes that the thermal loads play a leading role in the heat exchanger’s stress and deformation, and the heat exchanger can meet the strength requirements.