隔舌间隙对双流道泵瞬态流动特性的影响  

The Influence of Volute Tongue-impeller Gaps on the Unsteady Performance in Double-channel Pumps

作　　者：赵斌娟[1] 侯多华[1] 陈汇龙[1] 王瑜[1] 刘志斌[1] 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013

出　　处：《中国农村水利水电》2014年第5期118-123,共6页China Rural Water and Hydropower

基　　金：国家自然科学基金资助项目(51109094;51279067);江苏高校优势学科建设工程项目资助项目(苏财教[2011]8号)

摘　　要：为了研究隔舌间隙对双流道泵压力脉动特性的影响,采用大涡模型及网格滑移技术,结合全隐式多网格耦合算法,应用ANSYS-CFX对比转速为110的双流道泵进行3种隔舌间隙数下的全流道三维不可压缩湍流非定常数值模拟。在外特性模拟结果与实验结果对比验证的基础上,结合双流道泵自身特性,从泵的无阻塞性和内部流动的角度,探寻隔舌间隙数对双流道泵内压力分布、隔舌区附近的速度场及关键点压力脉动特性的影响规律。研究结果表明:随着隔舌间隙数的增大,压水室的高压区范围明显变大,泵内部静压分布规律性更好,隔舌间隙数越大,隔舌区附近的平均速度越小,流体在隔舌区域附近的流动更加平稳;不同隔舌间隙数的压力脉动的主频均为叶频,隔舌及蜗壳区压力脉动峰值处频率均为48.20Hz,同时随着隔舌间隙数的增大,压力脉动剧烈程度明显降低,这也是泵的水力效率有所提高的重要原因之一。适当增大隔舌间隙数有利于改善双流道泵水力性能及压力脉动特性。In order to study the characteristics of volute tongue-impeller gaps upon pressure pulsation, the large Eddy Simulation and sliding mesh model are adopted to simulate by means of ANSYS-CFX that solved the Navier-Stokes equations for the whole-channel three-dimensional unsteady turbulent flow. Based on external characteristics of simulation results compared with the experimental re- sults validation, an investigation is presented on the unsteady flow behavior near the tongue region of volute and double-channel im- peller pump with a specific speed of 110. The model was used to study the flow pulsations associated to the interaction between the impeller and the volute tongue. The results also show that the frequency of pressure fluctuation is dominated by the blade passing frequency and frequency peak of pressure pulsation between impeller and volute is 48. 200 Hz. With the increase in tongue gaps coef- ficient, the range of high pressure area can be enlarged obviously and static pressure distribution in the pump is uniform. The bigger coefficient of tongue-impeller gaps, the smaller of the average speed near the tongue. The main frequency of pressure pulsation fre- quency is the blade passing frequency, pressure pulsation peak frequency of impeller and volute is all 48.20 Hz, with the coefficient of tongue-impeller gaps increasing, the pressure pulsation intensity decreases obviously, that is one of important reasons why hy- draulic efficiency was increased. The coefficient of tongue-impeller gaps increases appropriately, which is helpful to improving the double-channel centrifugal pump hydraulic and pressure pulsation characteristics.

关 键 词：双流道泵 隔舌间隙 大涡模拟 压力脉动 

分 类 号：TH311[机械工程—机械制造及自动化]