摘要
本文通过实验研究了边界层转捩测量的一些方法和流场扰动对它们的影响,结果指出随机信号的均方根值在转捩过程中变化率较大,指示明确稳定,是测量转捩较准确有效的一种方法。同时,本文还研究了气流湍流度和噪声对边界层转捩区内最大扰动层的影响,指出这时在转捩区内仍存在最大扰动层,它位于 h≤0.2δ。最后提出:为提高转捩位置测量的精确度,必须进一步研究确定一个公认的转捩起、迄点的标记。
This paper describes the experimental results of the meas-uring transition methods and the effect of stream disturbance on them,and then indicates that the level of r.m.s.of random signal is moreeffective for the detecting transition because the difference of r.m.s.of random signal is larger and stabler in the transition process.Mean-while,in this paper,a reseach of the effect of turbulence and noise on thedisturbance in the region of transition has been made,and indicates thatthere is max.Disturbance and its position is 0.2δhigh while there existsturbulence and noise.Finally,a mark of indicating transition region mustbe studied further for the precision of measuring transition region.
关键词
边界层
转捩
测量
流场
扰动
boundary layer
transition measurement
measuring technique
