竖井贯流泵水力不稳定特性的改善研究

Study on improvement of hydraulic instability characteristics of shaft tubular pump

为有效抑制竖井贯流泵水力不稳定马鞍区的产生,该文基于URANS方法和FBM-CC湍流模型,开展了沟槽控制技术改善竖井贯流泵水力不稳定特性研究。在深度失速工况下,采用正交试验方法优选出显著改善竖井贯流泵水力性能的沟槽控制技术方案,利用边界涡量动力学和熵产理论深入研究沟槽控制技术改善竖井贯流泵水力不稳定特性的机理。研究结果表明:沟槽控制技术能够有效抑制马鞍区工况下叶顶间隙泄漏涡和叶片表面的流动分离,改善了叶片表面的边界涡量流(BVF)均匀分布情况,提高了叶轮的做功能力以及降低了叶轮区域的水力损失,显著提升了竖井贯流泵的水力性能,其中在深度失速工况时,扬程和效率分别提高了12.3%和1.75%,进而能够有效抑制水力不稳定马鞍区的形成。

To effectively suppress the occurrence of hydraulic instability saddle zone of the shaft tubular pump,based on URANS method and FBM-CC turbulence model,the research on improving the hydraulic instability characteristics of shaft tubular pump by the groove control technology is carried out.By using the orthogonal experiment,the optimal scheme of the groove control technology which can significantly improve the hydraulic performance of shaft tubular pump is obtained under the deep stall condition.The mechanism of the groove control technology to improve the hydraulic instability characteristics of shaft tubular pump is deeply studied by using the boundary vorticity dynamics flow diagnosis method and the entropy generation theory.The research results show that the groove control technology could effectively suppress the tip clearance leakage vortex and the flow separation of the blade surface under the saddle zone,and then improve the uniform distribution of the boundary vortex flow(BVF)on the blade surface.Meanwhile,the groove control techn ology improves the performance of the impeller and reduce the hydraulic loss in the impeller area.The groove control technology can significantly improve the hydraulic performance of the shaft tubular pump,in which the head and efficiency are increased by 12.3%and 1.75%respectively under the deep stall condition.Therefore,the groove control technology can e ffectively suppress the formation of the hydraulically unstable saddle zone.