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在西北工业大学 N F?3 低速翼型风洞内首次完成了两个直升飞机旋翼翼型的动、静态测压实验研究.简述了翼型动态实验所用的测试设备、仪器和实验方法,对影响翼型动态失速特性的两个主要因素??折合频率和振幅角进行了较为详细的分析研究.给出了相对厚度分别为9％ 和12％ 的两个直升飞机旋翼翼型的研究结果.“,”Design of high performance helicopter in P.R.C. now needs a better understanding of the effect of thickness chord ratio on dynamic stall characteristics of rotor blade. We took two thickness chord ratios: 9% and 12%. We used dynamic pressure method to measure pressure distributions for different angles of attack. Fig.1(a) shows the dynamic stall characteritics for lift. Then by numerical integration according to eq.(1), we computed the normal force defect coefficient K n . The smaller K n is, the better are the dynamic stall characteristics, K n decreases with increasing reduced frequency and with increasing oscillatory angle α 1 for rotor blade airfoil of 9% thickness chord ratio; the opposite is true for airfoil of 12% thickness chord ratio.