涡轮叶片双排气膜冷却效率叠加计算准确性研究  

Superposition Prediction Accuracy of Film Cooling Efficiency on Turbine Blade

作　　者：孟通[1] 朱惠人[1] 刘存良[1] 徐博涵 MENG Tong;ZHU Huiren;LIU Cunliang;XU Bohan(School of Power and Energy,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西北工业大学动力与能源学院,西安710072

出　　处：《西安交通大学学报》2018年第4期55-62,共8页Journal of Xi'an Jiaotong University

基　　金：国家重点基础研究发展计划资助项目(2013CB035702)

摘　　要：为进一步了解涡轮叶片上多排气膜间的流动及换热规律,选取对气膜冷却效率有影响的3种典型因素(叶片型面、吹风比、孔排方式)进行了实验及数值计算研究,验证了涡轮叶片气膜冷却效率叠加计算的适用性。结果表明:由于叶片型面曲率的存在,叶片吸力面为凸面气膜更容易吹脱,气膜孔后冷却效率叠加计算误差约为5%;叶片压力面为凹面气膜被压向壁面,前后排气膜间影响较大,叠加计算值比实验值约高13%。孔排排布方式对叠加计算结果同样有影响,叉排结构中气膜间呈现"块状叠加"现象,叠加计算值与实验值相比误差在5%以内。顺排结构中气膜呈现"层状叠加"现象,计算结果偏高,误差在10%左右。吹风比对冷却效率叠加计算准确性有较大影响,低吹风比时叠加计算较准确,随着吹风比增加叠加误差逐渐增大。针对叠加计算误差较大的工况,本文提出了相应的计算修正公式。Experimental and numerical simulations were conducted on turbine blade to figure out influences of three typical factors(vane curvature,blowing ratio and hole arrangement)on superposition prediction of film cooling efficiency.Results show that because of the convex blade surface on the suction side,jet is easy to be blown off and the computational error of superposition of film cooling efficiency is about 5%.On the pressure side,jet is easy to be pressed onto the wall and the prediction becomes inaccurate,hence the superposition calculation result is about 13%higher than experimental value.Another significant influence results from hole arrangement,the superposition prediction on staggered hole arrangement is nearly the same as the measured value,while it is much higher for inline arrangement.Blowing ratio also has an obvious influence on the accuracy of superposition prediction for film cooling holes on both pressure side and suction side.At low blowing ratio,results obtained by Sellers method agree well with the experimental ones,while as blowing ratio increases,the accuracy of superposition prediction is decreased.At last,modification of Sellers method is suggested to improve the prediction accuracy.

关 键 词：涡轮叶片 气膜冷却效率 叠加规律 实验研究 

分 类 号：V231.1[航空宇航科学与技术—航空宇航推进理论与工程]