一种轴对称变几何进气道设计方法

对带凹腔的圆锥流动进行了数值分析,就流场结构和总压分布与实验结果进行了比较,数值模拟结果与实验数据吻合较好,结果可信.数值模拟研究了不同几何构型的凹腔对圆锥流动的影响,分析并揭示了凹腔与圆锥流场的耦合流动特征.据此,对一种圆锥头部可移动的轴对称变几何进气道开展了方案设计及气动性能分析,并与相应定几何进气道进行了对比.结果表明:当来流马赫数高于设计马赫数时,后退圆锥头部可以调节进气道外压缩波系,保证流量系数达到0.99以上,采用该变几何技术,在不改变进气道内通道几何形状的前体下,可明显提高进气道的流量系数.

Design methodology of axisymmetric variable geometry inlet

Cone cavity flow was investigated with computational fluid dynamics(CFD) method.The flow structure and total pressure distribution were compared with experimental data.Results indicate that numerical results are in accordance with experimental data and the CFD method is creditable.Cone cavities with different shapes under various inflow conditions were studied;the coupling characteristic of cone cavity flow was analyzed and the flow phenomena downstream the cavity which were affected by cone cavity was presented.A kind of axisymmetric variable geometry inlet with movable cone tip was designed and its aerodynamic performances were compared with that of the relevant fixed geometry inlets.Results show that by translating cone tip backward toward the centerbody of the inlet,the exterior compression waves can be modulated and mass flow rate is obtainable above 0.99 when inflow Mach number exceeds the design point.The variable geometry technique would lead to an evident increase of mass flow rate without changing the geometry of internal compression duct of inlet.