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该文采用水气两相流Mixture模型,结合Realizable k-紊流模型对曲线阶梯连接段水流进行了三维紊流数值计算,得到了阶梯底板及边墙的压强分布规律。计算结果表明,曲线阶梯底板水平面压强沿步长方向呈倒“S”曲线分布,底板竖直面呈“C”字型分布,计算值和试验值变化规律和数值吻合。在斜面阶梯段,底板压强在横向上分布均匀;在水平阶梯段,底板压强在横向上分布不均匀,每个水平阶梯0.8倍步长处横向上存在两个高压中心。在阶梯凹角处存在负压,第二个水平阶梯(16#阶梯)负压值最大。每个阶梯边墙上存在一个高压中心和一个低压中心,高压中心在0.8倍阶梯步长底板处,低压中心在阶梯凹角的漩涡中心位置。由于进口流速大,阶梯前设置突扩突跌掺气设施,阶梯布置不同,该阶梯消能工的压强特性存在三维特性。
In this paper, three-dimensional turbulent flow is used to calculate the three-dimensional turbulent flow in the stepped connecting section by Realizable k-turbulence model. The pressure distribution of the stepped floor and the side wall is obtained. The calculation results show that the horizontal pressure in the step floor of the curve is distributed in the “S” curve in the direction of the step length, and the vertical plane of the floor is in the shape of “C”. The calculated and experimental values agree well with the numerical values. In the inclined step, the pressure in the bottom plate is evenly distributed in the horizontal direction. In the horizontal step, the pressure in the bottom plate is unevenly distributed in the horizontal direction. There are two high pressure centers in the horizontal direction at 0.8 times of each horizontal step. Negative pressure exists at the concave corner of the step, and the second horizontal step (16 # step) has the largest negative pressure. There is a high-pressure center and a low-pressure center on each step wall. The high-pressure center is at 0.8 times the step height of the floor, and the low-pressure center is at the vortex center of the step concave corner. Due to the large inlet flow rate, the sudden increase and decrease of air entrainment facilities in front of the ladder, the different arrangement of ladders, the three-dimensional characteristics exist in the pressure characteristics of the energy dissipater.