二元紊流发生器实验研究

本文给出了二元紊流发生器实验研究的结果,对不同文氏管通道型面所提供的一些典型的出口流场作了分析,并对某些工作状态下的激波振荡的特征作了介招。紊流发生器出口边界条件可以是音速出口,也可以是等压出口,尽管这方面的区别对于激波振荡特征以及分离包的尺度有显著的影响,但是对于出口流场的影响却是令人惊奇地微不足道。紊流发生器中常使用的提供总压图谱的畸变网可以使出口紊流度大幅度衰减。如果采用模拟板来代替畸变网,这一情况卽可以避免。

EXPERIMENTAL STUDY OF A TWO-DIMENSIONAL RANDOM FREQUENCY GENERATOR

Results are presented from an experimental investigation of the behavior of a two-dimensional random frequency generator. Typical flow fields obtained from tdifferent venturi contours are examined. Characteristics of the shock oscillation under certain operating conditions are described. The boundary condition at the exit section can be either sonic flow or constant pressure. While this boundary condition has been known to have major influence on the oscillation characteristics of the shock wave and extent of the flow separation, its effect on the flow field at exit is surprisingly negligible. Shaping screens which are often used in such generators to produce desired total pressure contours can drastically reduce turbulence intensity at the exit. This undesirable effect can be avoided by using a simulator plate instead.