发动机环形冷却风扇结构与参数对气动性能影响的研究

摘要

基于试验测试与计算流体动力学(CFD)分析的方法,研究发动机环形冷却风扇的结构与参数对其气动性能的影响.首先对一款环形风扇和一款开口风扇进行了气动性能试验,对比分析了两者气动性能的差异.然后建立了与试验情况一致的环形风扇气动性能的计算模型,计算分析了试验的环形风扇的气动性能,并与试验结果进行了对比分析,对比结果验证了模型的正确性.使用建立的模型,分析了环形风扇的圆环结构及尺寸参数对其气动性能的变化规律的影响.分析结果表明:环形风扇的圆环采用圆角结构可提高风扇的静压效率;圆环的相对轴向尺寸参数对环形风扇的气动性能有较大的影响,每款环形风扇都有一个叶片开口率使风扇的静压效率达到最佳;而圆环的相对径向尺寸参数对环形风扇的静压效率影响较小.%Based on the experimental testing and computational fluid dynamics analysis, a study on the effect of structure and parameters of an engine annular cooling fan on its aerodynamic performance was carried out.Firstly, the measurements of aerodynamic performances of an annular fan and an ordinary fan were conducted respectively, and the performance difference between the two type of fans was analyged.According to the test conditions of aerodynamic performance of the annular fan, a calculation model was developed and used to calculate the aerodynamic performance of the tested annular fan, which was verified by comparing the measured and the calculated data.By using the calculation model, the influence of circular ring structure and dimension parameters of annular fan on its aerodynamic performance was analyged.Results show that the fillet structure of annular fan's circular ring can improve the static pressure efficiency.The relative axial dimension parameters of the circular ring have great influence on the aerodynamic performance of the annular fan, and each annular fan has a blade exposure rate to make the static pressure efficiency achieve the best.However, the relative radial dimension parameters of the circular ring have little influence on the static pressure efficiency of the annular fan.