Simulation and experimental study on thermal state of engine compartment of commercial vehicle

YE Xiao， FU Jia-hong， ZHANG Yu， LIU Zhen-tao
（Power Machinery and Vehicular Engineering Institute， Zhejiang University， Hangzhou 310027， China）

Abstract： Aiming at the flow and temperature distribution，a 3D simulation model of the engine compartment of a commercial vehicle was established in FLUENT. The energy distribution under the full load condition and the curve of cooling module's flow characteristics，which were obtained separately through engine thermal balance test and vehicle road test，were used as the boundary conditions for simulation model. The simulation results verified by the vehicle road test indicate that the highest temperature of the cooling wind flow occurred at the top of the engine，mainly for the reason that the cooling module and the engine compartment are arranged in parallel and isolated by clapboard，and the shape of cooling wind tunnel is U. The results also indicate that the heat reflux of cooling wind could be controlled effectively because of the wind tunnel's isolation layout.
Key words： commercial vehicle； engine compartment； flow distribution； temperature ditribution； 3D simulation； FLUENT