CFD and Thermo-Mechanical Analysis for Heat Exchanger Used in Aero Engine

The multi-physics analysis using both the CFD and thermo-mechanical analysis is carried out to estimate the life of the heat exchanger which is operated under the conditions of high temperature and high pressure. First CFD analysis is carried out to obtain the distribution of flow, pressure and temperature around heat exchanger. The distribution of pressure, temperature and heat transfer coefficient obtained from the CFD analysis is transferred to the thermo-mechanical analysis using finite element analysis technique and is used as data to calculate the mechanical and thermal stress distribution in the heat exchanger. For the CFD analysis, it is considered a segment of heat exchangers using the symmetric and periodic conditions. For the thermo-mechanical analysis, the present finite element model considered both a segment and a half of full geometry by using the symmetric and periodic conditions. Alloy 625 is used for the present heat exchanger design due to its high strength at the elevated temperatures. The temperature-dependent physical properties of Alloy 625 for the thermo-mechanical analysis are used in a temperature ranges of 300∼1100K. Fatigue analysis is performed using a Goodman-diagram to assess the life of the present heat exchanger.