双向灯泡贯流泵站能量损失与压力脉动数值模拟研究

Numerical Simulation of Energy Loss and Pressure Pulsation in Bidirectional Bulb Cross-flow Pumps

摘要:

灯泡贯流泵站具备双向引水功能,在泵站工程中具有广泛的应用前景。然而,关于其正向与反向运行条件下的内部流动特性、能量损失及压力脉动差异的研究相对较少。本文采用非定常数值模拟方法,对灯泡贯流泵站在双向运行工况下的瞬态流动特性、能量损失机理与压力脉动规律进行了系统对比分析。研究结果表明:无论正向或反向运行,叶轮及下游通道均为能量损失的主要区域,其中反向运行工况下的总能量损失为正向工况的1.24倍。在压力脉动方面,正向工况下流道2的压力脉动峰值沿流动方向逐渐减小,而反向工况下流道1的峰值沿流动方向呈现出上升、下降、再上升和再下降的变化趋势,其中反向工况的峰峰值约为正向工况的2.55倍。本研究揭示了灯泡贯流泵站在正、反向运行下的典型流动特征及能量损失机理,可为双向运行泵站的优化设计及安全稳定运行提供理论参考。

Abstract:

Bulb cross-flow pumping stations possess bidirectional water intake capability and hold broad application prospects in low-head water diversion and flood control pumping station engineering. However, studies focusing on the systematic differences in internal flow characteristics, energy loss distribution, and pressure pulsation characteristics under forward and reverse operating conditions remain relatively limited at present. It adopted the unsteady numerical simulation method combined with entropy production analysis to systematically compare and analyze the transient flow features, internal energy loss mechanisms, and pressure pulsation variation laws of a bulb cross-flow pumping station under bidirectional operation conditions. The results indicated that, regardless of forward or reverse operation, the impeller region and its downstream flow passages were the primary regions of energy dissipation, with the total energy loss under reverse operation being 1.24 times that under forward operation. Regarding pressure pulsation, the peak values in passage 2 gradually decreased along the flow direction under forward operation, whereas under reverse operation, the peak values in passage 1 exhibited a complex pattern of increase, decrease, increase, and decrease along the flow direction. Notably, the pressure pulsation peak-to-peak values under reverse operation were approximately 2.55 times of those under forward operation. It revealed the typical flow features and energy loss mechanisms of bulb cross-flow pumping stations under both operating modes, providing important theoretical reference for the hydraulic optimized design and safe, stable operation of bidirectional pumping stations.