Vortex and wall pressure characteristics of hydraulic gate slots

Plate gates are the widespread applied hydraulic structures in water conservancy and hydropower engineering.Cavitation occurs frequently due to the complex flow patterns in the gate slots.In this paper,SST k-turbulence model was used to simulate the flow of the gate slot in order to analyze the influence of hydraulic and geometric parameters on the vortex and wall pressure characteristics of the gate slot.The contents of the paper include that the effects of width-depth ratio(W/D) on the pressure and its position of both the vortex center and walls of the gate slot,the pressure correlation between the vortex center and walls,and the effects of W/D and offset-depth ratio(Δ/D)on the pressure of the first and second separating zones downstream of the slot.The results show that the approach velocity of the coming flow directly dominates the pressures of the vortex and wall in the gate slot and the pressures of separating zone downstream of the gate slot,and show that with the increase of W/D the negative pressure of the vortex center in the slot increases at first,then decreases,and reaches the top value at about W /D 1.5,the position of the vortex center was related to both W Δ/D and flow velocity,while the position of negative pressure in the wall was only depend on W/D,the wall pressure value was closely related to that of the vortex center in linearity with the slope of 0.813,and the offset downstream of the slot has the better effect on modification of the pressure of the first separating zone,and when offset-depth ratio Δ/Dvalue is about 0.03–0.04 the pressures on the first and second separating zones would get the minimum values at the same time.