基于SPH方法的阶梯式溢洪道消能特性研究

SPH method-based study on energy dissipation characteristics of stepped spillway

为了研究阶梯式溢洪道的消能特性,本文通过二维建模的方式,利用光滑质点水动力学方法(SPH)对31阶阶梯式溢洪道的水流进行数值模拟,将模拟值与试验值进行了对比,并针对2种台阶数目和4种单宽流量共计8种工况,对不同工况的阶梯式溢洪道沿程水深、水流流速以及消能率进行了分析。结果表明,31阶阶梯式溢洪道水流的水面深度、流速和压强模拟值与试验值吻合较好;36阶和60阶阶梯式溢洪道沿程水深和水流流速与单宽流量呈正相关趋势,随着单宽流量的增加而增大,且在水流稳定之后,水面深度和流速都会维持在某一个值附近;而阶梯式溢洪道消能率沿程逐渐增大并在最后一级台阶处达到最大值。同时,当溢洪道体型一定,消能率随着单宽流量的减小呈上升趋势,当单宽流量减小至0.128 3 m^2/s,36阶和60阶阶梯式溢洪道的消能率分别达到了83.67%和82.86%。

In order to study the energy dissipation characteristics of the stepped spillway, the numerical simulation of the flow of the stepped spillway with 31 steps is made by the smooth particle hydrodynamic method(SPH) through two-dimensional modeling, and then the simulated value is compared with the experimental value, while the water depth along the way, the flow velocity and the energy dissipation rate of the stepped spillway under different operation conditions are analyzed for two kinds of step number and 4 kinds of unit discharges under total 8 operation conditions as well. The results show that the simulated values of the water depth, flow velocity and pressure of the flow of the stepped spillway with 31 steps are better coincide with the experimental values, while the water depths along the way and the flow velocities of the stepped spillways with 36 steps and 60 steps exhibit the trends of positive correlation with the unit discharge and are increased along with the increase of the unit discharge, while the water depths and flow velocities are to be maintained around a certain value after the stabilization of water flow. However, the energy dissipation rate of the stepped spillway gradually increases along the way and reaches the maximum value at the last step. Meanwhile, the energy dissipation rate exhibits an increasing trend along with the decrease of the unit discharge when the spillway shape is constant, while the energy dissipation rates of both the stepped spillways with 36 steps and 60 steps reach to 83.67% and 82.86% respectively when the unit discharge decreases to 0.128 3 m^2/s.