基于CFD-DEM耦合数值模拟的迷宫流道水沙运动规律研究

A Study on the Motion Law of Water and Particle in Labyrinth Channels Based on CFD-DEM Coupled Numerical Simulation

针对灌水器堵塞导致使用寿命过低等问题,该文以迷宫流道灌水器为对象,通过CFDDEM耦合数值模拟和试验相结合的方法,研究了灌水器结构参数、工作压力和沙粒粒径等因素对迷宫流道泥沙通过率和灌水器水力性能的影响,并采用LS-CWM激光粒度仪分析了灌水器出口泥沙级配变化情况.结果表明,灌水器内沙粒通过率与入口压力呈正相关关系,与沙粒粒径呈负相关关系;粒径在0.062 5~0.05 mm范围内时,角度对其通过率影响最大且显著;粒径在0.05~0.032 5 mm内时,各参数对通过率有影响但都不显著.试验分析方面,灌水器相对流量随着试验天数的增加而逐渐减少,整体呈下降趋势;通过数值模拟与试验分析相结合的方法,从宏观与微观的角度分析了迷宫流道内沙粒运动,这种方法大大提高了迷宫流道结构设计的效率.

In order to solve the problems such as the poor service life caused by the blockage of the emitter,the labyrinth flow emitter was used as the object. The CFD-DEM coupled numerical simulation and experimental methods were used to study the structural parameters of the emitter,working pressure and sand particle size. The influence of factors such as the sediment transport rate of the labyrinth channel and the hydraulic performance of the emitter was analyzed. The LS-CWM laser particle size analyzer was used to analyze the changes in sediment gradation at the outlet of the emitter. The results showed that there was a positive correlation between sand passage rate and inlet pressure in the irrigator,and a negative correlation with sand particle size. When the particle size was in the range of 0. 062 5— 0. 05 mm,the angle had the most significant effect on the pass rate; In the range of 0. 05— 0. 032 5 mm,each parameter has an effect on the passing rate but is not significant. In terms of experimental analysis,the relative flow rate of the emitter gradually decreased with the increase of the number of days of testing,and the overall trend showed a downward trend. Through the combination of numerical simulation and experimental analysis,sand movement in the labyrinthine flow channel was analyzed from a macroscopic and microscopic perspective. This method greatly improves the efficiency of the labyrinth runner design.