A sediment-laden fully developed turbulent shear flow, over an aerodynamically smooth erodible sand surface, was established in a large boundary-layer wind tunnel to investigate the influence of a nonuniform sand concentration distribution on velocity profiles and turbulence characteristics.; The Reynolds number of the flow, calculated from the free stream velocity and the boundary-layer thickness, covered a range from 3.2 x 10('5) to 1.2 x 10('6) as the concentration per mass varied between 0.0 and 0.7 which corresponds to a total transport rate per unit width of the tunnel of 0.042 kg/s-m.; Velocity profile measurements were made throughout the entire boundary layer, with emphasis on the inner layer. The mean and turbulent components were measured with a single hot wire. Sand concentration profiles were measured with a newly designed isokinetic sand sampler.; The analysis of mean velocity profiles demonstrates the applicability of the law-of-the-wall in the lower 10% of the boundary layer regardless of the sediment concentration. A method, based on similarity between turbulence relative intensity profiles, has been developed to evaluate the von Karman (kappa), and demonstrates its independence from sand concentration. The upper 90 percent of the velocity profiles is best described by the law-of-the-wake. The profile parameter (PI), increases with shear velocity from 0.6 for clear flow to an asymptotic value of 1.8 reached for main flow Reynolds number larger than 10('6) and sand concentrations larger than 0.6 near the bed. The velocity measurements display wake functions which are in excellent agreement with the function proposed by Coles (1956). It has also been shown that the root-mean-square velocity varies inversely with the local sand concentration. Finally, an empirical equation was derived to demonstrate a dependence of the sand transport rate on the square root of the elevation over the sand bed.; Among the most important conclusions are that sediment concentration does not affect the following: (1) The law-of-the-wall, in its domain of validity, (2) The value of the von Karman (kappa), (3) The wake flow function suggested in the literature for homogeneous fluids.
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机译：在一个大的边界层风洞中建立了一个在空气动力学上光滑的易蚀砂面上的，充满泥沙的充分发展的湍流剪切流，以研究不均匀的砂浓度分布对速度剖面和湍流特性的影响。根据自由流速度和边界层厚度计算出的雷诺数范围为3.2 x 10（'5）至1.2 x 10（'6），因为每质量浓度在0.0到0.7之间变化，相当于隧道每单位宽度的总运输率为0.042 kg / sm。在整个边界层进行速度分布测量，重点放在内层。平均和湍流分量用单根热线测量。用新设计的等速砂取样器测量砂浓度分布。对平均速度剖面的分析表明，不管沉积物浓度如何，边界层下部10％的壁法都是适用的。已经开发了一种基于湍流相对强度分布之间相似性的方法来评估von Karman（kappa），并证明了它不受沙浓度的影响。尾波定律最好地描述了速度曲线的最高90％。剖面参数（PI）随着剪切速度从0.6（对于清澈流向）到渐近值（对于在底部附近的主流雷诺数大于10（'6）且砂浓度大于0.6）达到渐近值而增加。速度测量显示的尾波函数与Coles（1956）提出的函数非常一致。还已经表明，均方根速度与局部砂浓度成反比。最后，得出了一个经验方程，以证明输沙速率与沙床高程平方根的关系。其中最重要的结论是，沉积物浓度不会影响以下各项：（1）在有效范围内的壁垒定律，（2）von Karman（kappa）的价值，（3）文献中针对均匀流体建议的尾流函数。
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