论文标题
垂直沉积物浓度分布分布以剪切引起的扩散率重新审视：基于同型分析方法的显式串联解决方案
Vertical sediment concentration distribution revisited with shear-induced diffusivity: An explicit series solution based on homotopy analysis method
论文作者
论文摘要
本研究重新审视了开放通道流中悬浮沉积物浓度的垂直分布，并特别注意沉积物扩散系数。如果认为湍流扩散率遵循抛物线型剖面，则床的扩散系数为零，在床附近很小。因此，仅一个人可能不足以将颗粒从床载层扩散到悬架区域。 Leighton＆Acrivos（J。FluidMech。，第181卷，1987年，第415-439页）引入了剪切引起的扩散的概念，该概念是由于固体颗粒之间的流体动力相互作用而引起的。这项工作考虑了结合剪切诱导的扩散概念的狩猎扩散方程，并重新研究了垂直沉积物浓度。分析解决方案是使用非扰动方法（即同同谱检测方法（HAM））得出的，并通过数值解决方案以及与可用的实验数据进行了验证。剪切诱导的扩散系数与垂直距离和变化的颗粒直径的行为已被物理解释。此外，考虑到相关的实验数据集，已经研究了重要的湍流因素，例如施密特数量倒数，阻碍沉降速度对浓度剖面的影响。
The present study revisits the vertical distribution of suspended sediment concentration in an open channel flow with a special attention to sediment diffusion coefficient. If turbulent diffusivity is considered to follow a parabolic-type profile, the diffusivity coefficient is zero at the bed and very small near the bed; so alone it may not be enough to diffuse the particles from bed-load layer to suspension region. Leighton & Acrivos (J. Fluid Mech., vol. 181, 1987, pp. 415-439) introduced the idea of shear-induced diffusion that arises due to the hydrodynamic interactions between solid particles. This work considers the Hunt diffusion equation incorporating the concept of shear-induced diffusion and reinvestigates the vertical sediment concentration profile. Analytical solution is derived using a non-perturbation approach, namely Homotopy Analysis Method (HAM), and is verified with numerical solution as well as compared with available experimental data. The behaviour of the shear-induced diffusion coefficient with vertical distance and varying particle diameters have been interpreted physically. In addition, the effects of important turbulent factors such as inverse of Schmidt number, hindered settling velocity on concentration profile, have been investigated considering relevant sets of experimental data.
