非对称来流下带隔板的二维短隔离段研究

Investigation for two-dimensional short isolator with a spacer under a asymmetric incoming airflow

关键词:  超燃冲压发动机  隔离段  弯曲隔板+  流场  数值分析

Key words:  Supersonic combustion ramjet engine  Isolator  Curve spacer~+  Flow field  Numerical analysis

摘要:

在隔离段中放置隔板,可以在满足气动性能的前提下缩短隔离段的长度。采用数值计算的方法对带隔板的二维隔离段与不带隔板的隔离段性能进行了比较,对非对称来流条件下不同进口附面层厚度隔离段内弯曲隔板的形状进行了研究,给出了非对称来流条件下隔离段内弯曲隔板的设计参数。结果表明,在进口马赫数为2,隔离段进口下板附面层厚度δ/H=0.24,上板附面层厚度为0时,通过放置弯曲隔板,在进出口压比相同与出口总压恢复系数基本不变的情况下,隔离段长高比减小了33%。

Abstract:

In order to reduce the length of the isolator without loss in efficiency,a method of putting the spacer in the isolator was applied.Computational fluid dynamics simulations were performed on the isolator with straight or curve spacer.Inflow conditions was supersonic flow with Mach 2.Under asymmetric incoming airflow,the effect of the curve spacer configuration on isolator performance was investigated.Design parameters for curve spacer design were given.The computational results indicate that the overall length could be reduced by 33 per cent without loss in static and total pressure recovery when the lower wall boundary layer thickness δ/H was equal to 0.24 and the upper wall boundary layer thickness δ/H was zero at the isolator entrance.