As the commercial vehicle increases staggeringly in China, environmental pollution and excessively fuel consumption can't be neglected anymore. Vehicle thermal management has been adopted by many vehicle manufactures as an ideal alternative to reduce fuel consumption and exhaust emission by its cost-efficient and effective merit. In addition, the components in heavy duty commercial vehicle engine hood may suffer overheat harm. Hence investigating the thermal characteristics in engine hood can be an effective way to identify and dismiss the potential overheat harm.
In terms of this, the paper has adopted CFD simulation method to obtain the comprehensive thermal flow field characteristics of engine hood in a heavy commercial vehicle. Then by analyzing the thermal flow field in engine hood, concerning optimization strategies were put forward to improve the thermal environment. The primary research objective here is a full 3D heavy duty commercial truck including front bumper, grill, cabin and all the under hood components. Three representative operation conditions namely idling, peak torque and rated power conditions were considered during simulation. Moreover take into account all the heat transferring phenomena like conduction, convection and radiation.
Research has shown that there exists serious air-recirculation zone in idling and peak torque conditions for the heavy duty commercial truck; over high temperature in some components and the bottom of the cabin has affected these components' normal function and cut down the cabin comfort as well in peak torque condition. The thermal environment can be improved a lot by adding wind shield on the heat exchangers to obstruct the air-reflux, installing deflectors to guide more cooling air into the heat exchangers and the heat shield to prevent some components from overheat harm.
This research method has been proved valid by the recent investigation of the thermal characteristics in the engine hood of a mining -dump car. Hence this paper could provide reference for earlier stage structural design and optimization of under hood in heavy commercial vehicle.