Influences of Infiltration on the Fluid Type and the Kinetic Parameters of the Shallow Open Channel Flow of a Slope

To analyze the theory of the influence of infiltration on the depth of the viscous sub-lay and kinetic parameters of shallow open channel flow on a slope, based on the Navier-Stokes equation, the flow velocity distributions of gentle slope and steep slope were derived. With the results, the influence of the infiltrate on the rate of the Reynolds number, Froude number, friction resistance coefficient, and rolling wave amplitude were studied under the conditions of slope planar steady non-uniform flow. The analysis results have been matched to the related experimental data. Results show that the laminar flow or turbulent flow appears under the flat slope condition caused by the infiltration rate, the flow velocity and depth, and the fluid type likely to be mainly associated with the process of influence between the initial permeability and steady seepage stage in the test. The fluid type is turbulent under the abrupt slope condition with a different infiltration rate and flow velocity and flow depth. On a flat slope or abrupt slope, the depth of viscous sub-lay is closer to or greater than the water depth; even if the infiltration rate was very small, and the depth of the viscous sub-lay increased with the increase of the kinematic viscosity coefficient but decreased with the increase of the infiltration rate, it would be impossible to see irrotational flow similar to open channel flow. The frictional resistance coefficient has a positive relationship with the Reynolds number, considering the capillary force and the infiltration rate influence. The influence factors of the rolling wave amplitude include the flow depth, infiltration rate and viscosity of water flow and the grade. The conclusions of this study provide a basis for experiment and theory studies on the shallow open channel flow of a slope. © 2019, The Editorial Board of Journal of Basic Science and Engineering. All right reserved.