二元曲面可调进气道流量系数精确预测方法

为了满足二元曲面可调进气道模态转换马赫数范围(来流马赫数为2.2~3.2)的流量要求,针对唇口平移、转动和转动+平移三种调节方案,基于理论分析和基准进气道的流场,提出了一种流量系数精确预测方法,并通过数值计算进行验证且获得了进气道的总体性能。结果表明:调节后的进气道流量系数与预测值完全相等,而且无需多次试算,符合设计预期,可拓展应用于轴对称进气道。相对基准进气道,唇口前移时流量系数和压缩效率同时增加,来流马赫数为2.5时出口总压恢复系数相等而增压比增加了14.6%;在降低相同流量系数条件下,后移唇口使得增压比和压缩效率均降低,来流马赫数为2.5时出口总压恢复系数基本相等而增压比减小了12.9%,转动唇口使增压比进一步减小了9.1%,唇口后移方案性能更优。 

Accurate prediction method of flow coefficient for 2D curved surface variable inlet

In order to meet the flow requirements of Mach number range of modal translation (incoming Mach number 2.2-3.2) for the 2D curved surface variable inlet, in view of three adjustment schemes of cowl translation, rotation and translation + rotation, based on theoretical analysis and the flow field of the reference inlet, an accurate prediction method of flow coefficient was proposed, and verified by numerical calculation, and the overall performance was obtained. The results showed that their flow coefficients were exactly equal to the predicted values and did not require repeated trial-calculation, which met the design expectations and could be extended to the axisymmetric inlet. In relation to the reference inlet, the flow coefficient and compression efficiency increased simultaneously as the cowl moved forward. The total pressure recovery coefficient of the exit was equal and the pressure ratio was increased by 14.6% at incoming Mach number 2.5. Under the condition of reducing the same flow coefficient, the backward movement of the cowl made the pressure ratio and compression efficiency lower, the total pressure recovery coefficient of the exit was basically equal and the pressure ratio was reduced by 12.9% at incoming Mach number 2.5, while the rotation of the cowl further reduced the pressure ratio by 9.1%, and the performance of cowl back movement scheme was better.