沉沙池是保障滴灌系统正常运行的重要设施之一,但灌溉期池内水沙“固液”耦合过程比较复杂,且难以通过单一物理模型进行结构优化。为进一步提高滴灌系统沉沙效率,设计了长流道直线型沉沙池;采用物理试验与数值模拟相结合的方式,研究有无调流板和不同调流板角度对池内水沙运动规律的影响。结果表明:Fluent软件可准确模拟池内“固液”耦合过程;后池设计的调流板起到了消能、降速和提高沉沙率的作用;相较于无调流板,有调流板时后池流速可降低70%以上,沉沙率提高12%以上;且60°倾角调流板池内流速最低,沉沙率最高,出口含沙量最低为1.12 g/L,沉沙率平均可达到71.26%。研究可为优化水工结构、提高沉沙池工作效率提供一定的技术支撑。

Desilting basin is one of the important facilities to ensure the normal operation of drip irrigation system. However, the solid-liquid coupling process of water and sediment in the basin during irrigation is complex, and it is difficult to optimize the structure by a single physical model. In order to boost the deposit efficiency of drip irrigation system, we designed a long channel straight-line desilting basin. Through physical experiment and numerical simulation, we examined the influences of flow-adjusting board and the angle of the flow-adjusting board on flow and sediment movement. Results manifest that the solid-liquid coupling process in the basin can be simulated accurately by Fluent software; the flow-adjusting board designed in the back basin plays the role of energy dissipation, speed reduction and improvement of sediment settling rate by reducing the flow velocity by above 70% and enhancing the sediment setting rate by over 12% compared with that in the absence of flow-adjusting board. In addition, when the inclined angle of flow-adjusting board is 60°, the flow velocity in the basin drooped to the lowest, while sedimentation rate hit the highest; the minimum sediment concentration at the outlet was 1.12 g/L, and the sedimentation rate averaged at 71.26%. The research findings offer technical support for optimizing hydraulic structure and improving the efficiency of desilting basin.