沟槽面与光滑面湍流边界层特性比较

应用ＬＤＶ技术对沟槽面及光滑面湍流边界层流速和湍流度分布进行了精细的测量，实验结果表明：与光滑面相比，沟槽面湍流边界层时均流速分布对数公式中具有较大的积分常数Ｃ值，且沟槽面湍流度最大值较小，但其出现的位置距壁面较远。另外，偏斜因子及平坦因子的分布特性区别不大，但是在近壁区内沟槽面结果波动较大。

Experimental Comparison between the Turbulent Boundary

By means of Laser Doppler Velocimeter, delicate measurements are made to examine the velocity distribution and the turbulence intensity in turbulent boundary layers over corrugated and flat surfaces. The measurements show that in contrast with flat surface, greater value of integral constant C in log law formula is obtained for corrugated surface, and the maximum value of turbulence intensity is smaller, which occurs at a greater distance from the corrugated surface. It is also shown that both the skewness factor and the flatness factor for the two cases have no evident difference in distribution.