关于跨声速流动的敏感性

ON THE SENSITIVITY OF TRANSONIC FLOW

本文从大量实验事实出发,分析了细长锥-柱体跨声速流场结构随来流马赫数M_∞的变化。指出这种结构外形圆柱段上的流动随来流M_∞数的变化呈现一种特殊的敏感特征,由此提出了跨声速上、下敏感马赫数的概念。研究表明,圆柱段上的流动并非在整个跨声速范围都十分敏感,其真正敏感区域是介于上、下两个敏感马赫数M_(us)、M_(ls)之间的区域。这一特征对跨声速流动中的若干结果有一定概括性。对跨声速领域理论分析、数值计算、开展实验及实际飞行均有一定指导和参考意义。

Proceeding from a large number of experimental results, this paper analyzel the variation of structure of transonic flow field over slender cone-cylinder with free-stream Mach number M∞. It is indicated that a peculiar sensitivity feature is demonstrated in the variation of the flow over the cylinder with incoming Mach number M∞, from which concept of transonic upper and lower sensitive Mach numbers is presented. Examination shows that the transonic flow over the cylinder is not always sensitive in entire transonic regime, the most sensitive region lies only in an interval bounded by the upper and the lower Mach numbers Mus, Mls. This characteristic is some summary to a certain number of results obtained in transonic flow study. Also, this discovery has certain guidance and referential significance to theoretical analysis, numerical simulation, experiment and practical flight in transonic field.