Numerical simulation and optimization design of the EGR cooler in vehicle

The EGR(exhaust gas reeirculation)technique can greatly reduce the Nox emission of diesel engines,especially when an EGR cooler iS employed.Numerical simulations are applied to study the flow field and tempemture distributions inside the EGR cooler.Three different models of EGR cooler are investigated,among which model A is a traditional one,and models B and C are improved by adding a helical bafile in the cooling area.In models B and C the elltry directions of cooling water are different,which mostly influences the flow resistance.The results show that the improved structures not only lengthen the flow path of the cooling water,but also enhante the heat exchange rate between the cool and hot media.In conclusion we suggest that the improved Structures are more powerful than the traditional one.