几何尺寸对高超声速进气道气动性能的影响

为了探索模型缩尺比对高超声速进气道气动性能的影响，对不同缩尺比的二元高超声速进气道开展了数值模拟研究，结果表明：随着缩尺比的增大，进气道流量系数、隔离段出口总压恢复系数和马赫数均逐渐增大，而静压比逐渐减小，且来流马赫数越高，上述参数变化幅度越大。由理论与数值模拟分析可知，上述现象主要是由于不同缩尺比下，进气道当地雷诺数不同，导致进气道附面层相对厚度变化，进而影响进气道气动性能。理论分析了进气道总压恢复系数与缩尺比的定量关系，就进气道而言，进气道进口处附面层相对厚度减小1%，隔离段出口总压恢复系数提高约0.7%。

Effect of Geometric Dimensions on Aerodynamic Performance of Hypersonic Inlet

To investigate the effects of size construction ratio of model on hypersonic inlet's aerodynamic performances, numerical simulation for hypersonic inlet model with different size construction ratios was carried out. The results indicated that as the construction ratio increased, the total-pressure recovery coefficient, Mach number and the mass flow coefficient of inlet isolator's exit all raised while the static pressure ratio declined. And the trend is more apparent at higher free-stream Mach number. Theoretical analysis and numerical simulation show that the illustrated phenomenon is mainly attributed to the change of the relative thickness of boundary layer at different conditional Reynolds numbers. Through the theoretical analysis on the quantitative correlation between the total-pressure recovery coefficient and the size construction ratio, as for the inlet model investigated in this paper, when the relative thickness of boundary layer decreased by 1%, the total pressure recovery coefficient of inlet isolator's exit would increase by about 0.7%.