It is important to study the mechanism between the cascade blade profile parameters and the thrust reverser effectiveness. The efficient and reliable numerical axisymmetric models have been established and the special method to deal with the inner core passage is proposed. The effect of blade exit angle and fan nozzle pressure ratio on thrust reverser effectiveness and discharge coefficient is investigated. The calculated and the available experimental results are firstly compared, which shows that the calculated and the experimental data are identical. The thrust reverser effectiveness firstly notably increases as the blade exit angle increases from 30° to 50°, and then it changes little and even declines when the blade exit angle continues to increase. When the blade exit angle equals to 50°the thrust reverser effectiveness reaches its maximum value. When the blade exit angle increases from 30°to 60°, the discharge coefficient changes initially little and then declines severely when the angle is more than a critical value. The discharge coefficient varies little for the medium blade exit angle 40°-50°, as the pressure ratio increases, but when the blade exit angle is out of the range, it changes seriously. The discharge coefficient increases creepily for the little value of the blade exit angle and changes little for the large value of the blade exit angle when the pressure ratio increases from 1.1 to 1.9.%航空发动机叶栅反推器叶型参数与反推效率、流量系数之间的规律对于反推装置的设计具有重要意义.建立了外涵叶栅反推器的轴对称计算模型,给出了内涵计算域的有效处理方法.利用数值模拟手段研究了叶片出口安装角、外涵入口压比的变化对反推效率、流量系数等的影响规律,并将计算结果与可能得到的试验结果的数据点进行了比较.结果表明,计算结果与实验结果吻合.出口安装角在30°-50°这个范围内时,随着出口安装角的增大,反推效率明显上升.继续增大出口安装角至60°,反推效率变化趋于平缓,甚至有所下降.在50°时反推效率达到最大值.随着出口安装角的增大,流量系数基本不变,超过某一临界值后急剧下降.对40°-50°这些中等大小的叶片出口安装角,压比对反推效率的影响不大.叶片出口安装角超出该范围,压比对反推效率的影响较大.当出口安装角较小时,随压比增大,流量系数缓慢增大.当出口安装角较大时,流量系数随压比变化不大.
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