Numerical simulation of scouring funnel in front of bottom orifice

• Published in: Journal of hydrodynamics. Series B 2013-07, Vol.25 (3), p.471-480
• Main Author: 薛万云 槐文信 李志伟 曾玉红 钱忠东 杨中华
• Format: Article
• Language: English
• Subjects: Computational fluid dynamics; Computer simulation; Densimetric Froude number; Engineering; Engineering Fluid Dynamics; Eulerian model; Fluid flow; Funnels; Hydrology/Water Resources; Mathematical models; Numerical and Computational Physics; numerical simulation; Porosity; Sand; Scouring; scouring funnel; Simulation; 两相模型; 冲刷漏斗; 实验室测量; 底孔; 数值模拟; 液压参数; 相互作用; 砂土层
• ISSN: 1001-6058; 1878-0342
• DOI: 10.1016/S1001-6058(11)60386-8

The scouring funnel in front of a bottom orifice under the condition of fixed water levels is simulated by using an Eulerian two-phase model, with onsideration of the flow-particle and particle-particle interactions. The predictions of the scouting funnel shape agree well with laboratory measurements. The flow-field characteristics of the two phases and the influences of the hydraulic and geometric parameters on the shape of the scouring funnel are analyzed on the basis of the computation results. It is revealed that the non-dimensional maximum scour hole parameters, the depthdm / do, the length l,. / do, and the half-width w / do, are linearwith the densimetric Froude number Fro , the main parameter describing the scour hole, the centerline scour depth Dc and the half-scour width Wr vary according to a power law, and the transverse scour profiles exhibit strong similarities, the velocity distribution of the water is confined within the sink-like area near the orifice, and the mutual impact of the flows at the azimuthal sections and the resistances of the walls and the sand layer produce a vortex in the scour hole, that makes the sand particles to be suspended in the water, the exchanging water in the pore water is the main contributor in forcing the sand to move, and transporting the sand in the same direction as the pore water along azimuthal sections.