乘用车发动机前舱温度场优化  

Optimization of Underhood Temperature Field for a Passage Car

作　　者：刘国庆[1,2] 杨万里[2] 邓晓龙[2] 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]奇瑞汽车股份有限公司,芜湖241009

出　　处：《中国机械工程》2013年第9期1252-1257,共6页China Mechanical Engineering

基　　金：国家高技术研究发展计划(863计划)资助项目(2006AA110106);内燃机燃烧学国家重点实验室开放课题基金资助项目(K2010-04)

摘　　要：为了分析某整车发动机舱温度场试验开发过程中出现的传动轴油封和蓄电池表面局部温度超标现象的原因,建立了发动机舱CFD流动与传热三维分析模型,结合试验获得舱内主要发热部件壁面温度边界条件,并考虑辐射换热的影响,求解了试验工况前舱内流场分布和温度超标部件表面温度。计算结果表明:传动轴油封表面温度偏高的主要原因是其离高温热源近而附近流速很小;蓄电池壁面温度超标的原因是经散热器和风扇的冷却气流因回流被循环加热后直接吹向蓄电池表面。为此,在传动轴油封和蓄电池附近分别增加了冷风导流和隔热导流结构,并进行模拟优化和试验验证。试验结果表明:传动轴油封和蓄电池表面的温度均显著下降,有效解决了发动机前舱温度过高的问题。During underhood temperature field experimental development for some passage cars, surface temperature of drive shaft oil seal and battery is in excess of the limit. To find the reason, de- tailed CFD model of underhood for air flow and heat transfer analysis was established. The tempera- ture boundary conditions for main heat resources were obtained by experiments, and the radiation heat transfer was also considered. The air flow distribution and temperature field in underhood under test conditions were solved. Simulation results indicate that, over high temperature of drive shaft oil seal is because of that oil seal is very close to hot resource while the air flow velocity around it is small, for battery it is owing to flow circumfluence through radiator and fan which causes that air blowing to the battery surface is repeating heated. Based on this, structure to guide cool air and heat insulation were added near drive shaft oil seal and battery, and their shapes were optimized by CFD simulation, and the final effect was validated by experiments. It is shown that measured temperature of oil seal and battery reduces significantly, the underhood temperature overhigh issues are then eliminated.

关 键 词：前舱 温度场 计算流体力学 辐射换热 导流 

分 类 号：U461[机械工程—车辆工程]