淤泥对平面钢闸门启门力影响的数值仿真分析

为了准确模拟闸前泥沙淤积对平面钢闸门启门力的影响,将闸前泥沙考虑为由粗细颗粒组成的宾汉体,闸门在开启过程中,粗颗粒之间的碰触和相对滑动产生了摩擦剪切应力,而细颗粒之间的絮凝作用在闸门开启的瞬间提供了极限剪切应力,这两种剪切应力之和称为泥沙临界屈服应力.闸门启动时,必先克服临界屈服应力.基于VOF（volume of fluid）的三维非稳态两相流k T-εT模型,引入宾汉体模型,考虑泥沙临界屈服应力,建立起闸前泥沙淤积对平面钢闸门启门力影响的数值仿真模型,并应用该仿真模型计算了天津宁车沽防潮闸在闸前有泥沙淤积情况下的启门力,计算结果与实测资料吻合较好.

Numerical Simulation Analysis on Effect of Silt Sediment on Lifting Force of Plane Gate

In order to accurately simulate the effect of the sediment deposition on the lifting force of plane gates, the sediment in front of gates is considered to be Bingham which consists of the coarse and the fine particles. In the open- ing process, the contact and the relative sliding among the coarse particles provide friction shear stress; Flocculation among fine particles provides the limit shear stress at the moment of the gate opening. The sum of the two kinds of stresses are known as the sediment critical yield stress. During the gate opening, the gate must overcome the critical yield stress firstly. Based on the three-dimensional, non-steady-state, two-phase-flow computed model kT-εT model and VOF（volume of fluid） method, the Bingham model was introduced in the paper. Considering the sediment critical yield stress, a numerical simulation model of the impact of sedimentation on gate opening was established. And the simulation model was applied to calculate the lifting force under the circumstances of sediment deposition in front of the gate of the Ningchegu floodgate in Tianjin. The results coincide with the prototype observation data well.