Abstract:From the perspective of structural changes of impeller passage, the internal flow field in doublechannel pumps and flow characteristics were studied. Standard k-ε turbulent model and implicit multigrid coupling method were applied to numerically simulate the threedimensional inner turbulent flow of the wholepassage of three types of pumps (scheme a:up circle type, scheme b:straight line type, and scheme c:down circle type). Under the same flow rate conditions, hydraulic performance were compared and optimal doublechannel impeller passage structure were explored between the three types of pump. It was found that different impeller channel structure presented a certain degree of regularity and diversity of velocity & pressure distribution under the design conditions. Efficient proper volume of impeller channel has been increased both in scheme a and scheme c. In comparison, scheme a has the superior nonblocking performance and the minimum hydraulic efficiency, with a clear pressure drop at the passage inlet; scheme c has the maximum hydraulic efficiency and the lowest head .Comprehensive analysis of the hydraulic performance and nonblocking performance, scheme b with the highest head of 14.46 m and the higher hydraulic efficiency of 78.24%,has superiority,Analysis of steady variable condition properly based on numerical simulation and corresponding test verification,scheme b is the optimum structure of impeller passage in doublechannel pumps.
[1]Jin Jie, Fan Ying, Han Wei, et al.Design and analysis on hydraulic model of the ultralow specificspeed centrifugal pump[J].Procedia Engineering, 2012, 31:110-114.[2]Shojaeefard M H, Tahani M, Ehghaghi M B, et al.Numerical study of the effects of some geometric characteristics of a centrifugal pump impeller that pumps a viscous fluid[J]. Computers & Fluids,2012, 60: 61-70.[3]Cheng Xiaorui, Li Rennian. Parameter equation study for screw centrifugal pump [J]. Procedia Engineering,2012,31: 914-921.[4]程效锐. 双流道泵内部流场数值模拟及性能预测[J].水泵技术,2006(6):17-20.Cheng Xiaorui.Numerical simulation internal flow field and performance prediction of double channel pumps[J].Pump Technology,2006(6):17-20.(in Chinese)[5]刘厚林, 袁寿其, 施卫东,等.双流道泵叶轮内湍流的数值模拟[J].农业工程学报,2002,18(2):9-12.Liu Houlin, Yuan Shouqi, Shi Weidong, et al. Numerical Simulation for incompressible turbulent flow in impellers of doublechannel pumps[J]. Transaction of the CSAE, 2002,18(2):9-12.(in Chinese)[6]Raúl Barrio, Jorge Parrondo, Eduardo Blanco.Numerical analysis of the unsteady flow in the neartongue region in a volutetype centrifugal pump for different operating points[J]. Computers & Fluids,2010,39: 859-870.[7]赵斌娟,袁寿其,刘厚林,等.双流道及双叶片式叶轮内流场的PIV测量与比较[J].农业机械学报,2008,39(12):82-85.Zhao Binjuan,Yuan Shouqi,Liu Houlin,et al.PIV measure meat and comparision of inner flow inside the double channel and two blade impeller[J].Transaction of Chinese Society for Agricultural Machinery,2008,39(12):82-85.(in Chinese)[8]李亚林,袁寿其,汤跃,等.离心泵内流场PIV测试中示踪粒子跟随性的计算[J].排灌机械工程学报,2012,30(1):6-10.Li Yalin,Yuan Shouqi,Tang Yue,et al.Analysis of tracing ability of PIV seeding partides in flow fileds of centrifugal pumps[J].Journal of Drainage and Irrigation Machinery Engineering,2012,30(1):6-10.(in Chinese)[9]张兄文,李国君,李军.离心泵蜗壳内部非定常流动的数值模拟[J].农业机械学报,2006,37(6):63-68.Zhang Xiongwen, Li Guojun, Li Jun.Numerical simulation of unsteady flow in centrifugal pump volute[J].Transaction of Chinese Society for Agricultural Machinery,2006,37(6):63-68.(in Chinese)[10]Zhao Binjuan, Yuan Shouqi, Liu Houlin. Three dimensional coupled impellervolute simulation of flow in pump based on sliding mesh and RNG k-ε model[J].Chinese Journal of Mechanical Engineering, 2006,19(1):59-62.