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自由液面的捕捉应用VOF法,气液两相流时均方程采用RNG湍流模型封闭,采用数值模拟的方法计算了6种工况下,三角形波浪底板消力池自由水跃的流体力学特性.采用有限体积法离散微分方程,速度与压力耦合求解使用了压力隐式算子分裂PISO(Pressure-Implicit with Splitting of Operators)算法.研究发现:波浪形底板表面附近有漩涡产生,漩涡沿顺时针方向旋转,漩涡的尺寸沿程逐渐减小;沿程横断面上的最大流速在不同工况下有相似的衰减规律;在闸门附近产生紊动耗散率和紊动动能最大值及最大变化梯度,随进口弗劳德数的增大紊动能和耗散率最大值也增大;理论消能率和实际消能率均随进口弗劳德数增大而增大.
VOF method was used to capture the free surface. The mean-square equation of the gas-liquid two-phase flow was closed by RNG turbulence model. The hydrodynamic characteristics of the free-jerk at the triangular wave floor was simulated under six conditions by numerical simulation. Using finite volume method, the pressure-implicit with Splitting of Operators (PISO) algorithm is solved by the coupling of velocity and pressure, and the vortexes are generated near the surface of wavy bottom plate. The size of the swirl and swirl decreases gradually along the process; the maximum flow velocity in the cross section along the process has a similar attenuation law under different operating conditions; maximum and maximum turbulent kinetic energy dissipation and maximum change gradient occur near the gate, As the inlet Froude number increases, the maximum turbulent energy and the maximum dissipation rate also increase. Both the theoretical energy dissipation rate and the actual energy dissipation rate increase with the increase of imported Froude number.