基于SPH消力池内陡坡水跃的数值模拟

为了满足明渠水流入流的边界条件,扩展SPH方法在明渠恒定流模拟中的应用,本文建立SPH方法的出入流模型,通过设置相应的出入流边界条件,研究不同坡度下消力池内陡坡水跃特性。针对两种不同流量,对斜坡坡角θ分别在20°、30°、45°条件下的陡坡水跃进行数值模拟。模拟结果与文献中的实验结果进行对比分析,结果表明:出入流模型能为陡坡水跃的数值模拟提供稳定的水流。各陡坡不同流量下水面线的变化趋势基本相同,误差均在±10%内;相同坡角时,单宽流量为0.063 m~2/s的消能效果均大于单宽流量为0.105 m~2/s的消能效果。该方法处理出入流边界简单,合理准确,能够较好地模拟不同坡度下消力池内陡坡水跃,得到陡坡水跃特性,具有一定的可行性和可靠性。

SPH method-based numerical simulation of steep-slope hydraulic jump in stilling pool

In order to satisfy the boundary condition of open channel inflow and extend the application of SPH method in the simulation of the open channel steady flow，a SPH ( smoothed particle hydrodynamics) -based inflow-outflow model is established herein，and then the characteristics of the steep-slope hydraulic jump in stilling pool under the conditions of different gradients are studied through setting the corresponding inflow-outflow boundary conditions． For both different flow rates，the steep-slope hydraulic jumps under the conditions with the slope angles of 20°，30° and 45° are numerically simulated respectively． The simulated result is comparatively analyzed with the experiment results given in the relevant literatures and the result shows that the inflow-outflow model can provide stable flow for the numerical simulation of the steep-slope hydraulic jump，from which the changing trends of the water surface lines under the conditions of different flow rates of all the steep-slopes are basically the same with the error within 10%，while the energy dissipation effects of all the flow rates of 0. 063 m3 /s are larger than those of the flow rates of 0. 105 m3 /s，when the slope angles are the same． This method can simply，reasonably and accurately deal with the inflow-outflow boundaries and better simulate the steep-slope hydraulic jumps in stilling pool under the conditions of different gradients for obtaining the hydraulic jump characteristics concerned，thus has certain feasibility and reliability．