轴流泵装置三维非定常湍流流场的数值模拟

为了分析轴流泵内部流场的瞬时特性,结合非定常不可压牛顿流体的控制方程和RNGk-ε双方程湍流模型,考虑各过流部件之间的相互干涉作用,在Fluent软件中应用SIMPLEC算法和滑移网格技术,在一个完整的转动周期中对4000ZLQ53.5-6.6 JS型立式轴流泵全流道内的三维湍流流场进行了数值模拟.给出了在叶片角为0,°设计流量工况为53.5 m3/s时叶轮进出口干涉面的压力、速度与涡量云图,直观地显示了一个转动周期内叶轮干涉面的干涉情况.对干涉面物理量云图进行对比分析,得出了轴流泵内部流场瞬时特性的数值模拟计算结果.引入动态特性预测方法,对瞬时计算结果时均化,将动态特性预测结果与泵站的现场测试数据进行对比,证明了该数值模拟方法的可行性.这表明,计算所采用的轴流泵装置非定常三维湍流流场的数值模拟方法,是人们认识轴流泵流场流动与干涉机理的有效理论手段.

3D numerical simulation on unsteady turbulence flow in axial flow pump system

In order to analyze inner flow transient performance of an axial flow pump,based on the unsteady incompressible flow governing equations and the RNG k-ε turbulence model,the SIMPLEC method and sliding mesh technique were used to numerically simulate the 3D turbulent flow of the full passage in a vertical axial flow pump within a complete rotating cycle.The interaction between pass-flow parts was taken into consideration.The type of pump was 4000ZLQ53.5-6.6JS.The pressure,velocity and vortices distributions on the interaction surface were given under the conditions that blade angle was zero and the discharge was 53.5 m3/s.The results show respectively the variation of flow field characteristics in the impeller,and full flow passage in one rotating cycle.Numerical simulation results were obtained through comparative analysis on the distribution on the interaction surface.By introducing dynamic performance prediction,doing time average and comparing the results of dynamic performance prediction with test data from a pumping station,the method proves to be credible.It is indicated that the 3D unsteady turbulent simulation is effective for understanding the axial flow pump flow field,as well as the interaction mechanism.