基于虚拟正交试验的发动机冷却风扇设计参数优化

汽车冷却风扇的设计参数决定其工作性能,进而对整车散热性能有直接影响。采用计算流体力学的方法,分析风扇轴向伸入距离、风扇与风扇罩径向间隙和风扇旋转中心偏移距离三种不同参数对散热器进风量和风扇有效功率的影响规律。在此基础上,通过虚拟正交试验的多目标耦合分析,得到风扇设计参数的优化方案。并通过数值仿真与整车热平衡试验对优化方案进行验证。结果显示,优化后车型在模拟爬坡工况下,散热器,冷凝器进风量和风扇有效功率分别提升10.89%、4.08%和12.78%,发动机表面温度降低0.91℃,发动机舱散热性能显著提升,内部温度分布状况明显改善。

Parameter Optimization of Cooling Fan Based on Virtual Orthogonal Test

The design parameters of automobile cooling fan determine its working performance,which has a direct impact on the heat dissipation performance of the whole vehicle.Computational Fluid Dynamics technique was adopted to analyze the effects of axial extension distance of fan,radial spacing between fan blade and fan cover and deviation distance of fan rotate center on intake air volume and effective power of fan.The optimization scheme of design parameter for cooling fan was obtained through virtual orthogonal test.The real effects of optimized scheme were verified by simulation and real vehicle test.The results showed that the thermal performance of vehicle and the internal temperature distribution in engine compartment were improved significantly under simulated climbing conditions,with effective power of fan static pressure and the air flow through radiator and condenser increasing by 12.78%,10.89%and 4.08%under climbing condition.