Thermodynamic simulation of exhaust gas recirculation coolers used on diesels based on finite element method

The thermodynamics of exhaust gas recirculation (EGR) coolers plays a very important role for reducing oxides of nitrogen (NOX) emissions of diesel engines. Using the ANSYS software, some fluid thermodynamic models of EGR coolers were established by using the finite element method (FEM); and the temperature fields of gas fluids in the EGR coolers were simulated and verified by comparing the experimental results from some literatures. Based on the FEM models, furthermore, cooling efficiencies of the EGR coolers with different diffuser structures and different numbers of cooling tubes were analyzed and discussed. The comparison results show that, for the same dimension of EGR coolers, their cooling efficiencies can be increased up to five or thirteen percents by replacing their column diffusers with cone diffusers or by properly selecting the tube numbers of the EGR coolers.