壁面加热边界条件对湍流扩展的自相似性的影响

Effect of Heated Wall on Extended Self-Similarity of Wall Turbulence

用热线风速仪测量了风洞中壁面加热和不加热平板湍流边界层不同法向位置的瞬时流向速度的时间序列 ,研究了壁面加热的边界条件对流向速度增量的 p阶结构函数的扩展的自相似性和层次结构模型的影响 .实验结果表明 ,壁面加热的边界条件对流向速度增量的结构函数扩展的自相似标度律的相对标度指数ζ( p,3 )和层次结构模型中间歇参数 β、最奇异指数 γ的影响明显存在 .

Longitudinal velocity measurements at different vertical location in a turbulent boundary layer over a heated or an unheated plate in a wind tunnel have been carried out by using hot wire anemometer. The extended self-similarity and hierarchical structure model for the p-th order structure function of velocity increment have been analyzed. Experimental evidence is given which shows that the effect of heated wall boundary condition on the intermittence degree β and singular parameter γ of the hierarchical structure model clearly exists.