Fundamental problems on CFD simulation of convective heat transfer in underhood
LIU Guilan;ZHAO Lanping;YANG Zhigang;Institute of Refrigeration and Cryogenic Engineering,Tongji University;Shanghai Automotive Wind Tunnel Center,Tongji University;
To further decrease the maximum temperature in underhood by the rational selection of inlet and outlet sizes and the layout of components in undehood,three turbulence models,including standard k-ε model,RNG k-ε model and realizable k-ε model,and two wall functions are used to simulate the temperature field of underhood. The comparison of simulation and tests indicates that realizable k-ε model and enhanced wall function are more suitable for simulation of heat flow field. A series of calculation using CFD are done,including different sizes of inlet and outlet and different distances between heat exchanger and engine,to analyze the influence on the underhood temperature. The results show that the size of inlet and outlet has great effect on the maximum underhood temperature.