排水泵站流场特性及漩涡特征数值模拟

Numerical Simulation of Flow Field Characteristics and VortexCharacteristics of Drainage Pumping Station

为研究不同工况下排水泵站中液体流动的特性,借助计算流体动力学CFD软件对泵站内3种不同液位进行数值模拟,以三维非稳态雷诺方程为基础,采用标准纳维-斯托克斯模型建模以及两相流的VOF方法计算。对不同水位下的液体流动进行分析,以确定初始水位最佳值。研究表明:仅使用经验公式分析泵站最低水位时与实际相比可能存在一定的误差,需考虑泵站前池的几何特性以及流体动力学特性。当水位低于临界值时,在泵入口处出现非稳态涡结构,泵站内出现停滞区。同时,对大型泵站设计时宜借助数值模拟软件构建流体动力学模型,模拟发生漩涡的可能性,并提供改善措施和方案。

To explore the liquid flow characteristics in the drainage pumping station under different working conditions,three different liquid levels in the pumping station were numerically simulated by means of computational fluid dynamics software.Based on the three-dimensional unsteady Reynolds equation,the standard Navier-Stokes model was used for modeling and the VOF method for two-phase flow was used for calculation.The liquid flow under different water levels is analyzed to determine the optimal initial water level value.The research showed that there may be a certain error compared with the actual when only using the empirical formula to analyze the minimum water level of the pumping station.The geometrical and hydrodynamic properties of the pumping station forebay need to be considered.When the water level was lower than the critical value,an unsteady vortex structure would appear at the inlet of the pump.Therefore,when designing large-scale pumping stations,it is advisable to use numerical simulation software to build a fluid dynamic model,simulate the possibility of vortex occurrence,and provide improvement solutions.