摘要
引入边界涡量流(BVF)理论对叶片进行诊断,探究叶片表面BVF分布与水力性能的关系,为将来改进设计提供诊断依据.选用IS150-125-250型离心泵(参考离心泵)基本参数,基于速度系数法和二元理论自编程序,设计出新的离心泵叶轮.与参考叶轮相比,新设计的叶轮进口端空间弯扭特征明显.采用RANS控制方程组和标准k-ε湍流模型对设计离心泵和参考离心泵全流道内流场进行数值模拟,对比分析两者含设计工况点在内的13个工况点的水力性能.同时根据设计离心泵和参考离心泵叶轮内流场计算结果,基于BVF诊断方法,对两叶轮叶片压力面和吸力面BVF分布进行对比分析.结果表明:相比参考离心泵,设计离心泵在小流量工况下扬程和效率较高,最高效率可提高5.3%.参考离心泵叶片表面BVF峰值较大,而设计离心泵叶片表面BVF分布更均匀,变化也更平坦,说明设计离心泵叶轮能更有效地抑制流动分离等不良流动的发生,改善了离心泵的水力性能.
In order to provide diagnostic evidence for optimizing design,the boundary vorticity flux（BVF） theory was introduced to diagnose blades,with the purpose of exploring the relationship between BVF distribution on blade surface and hydraulic performance.Based on two-dimensional flow theory and velocity coefficient theory,applying the parameters of IS150-125-250 centrifugal pump,a centrifugal-pump impeller was designed.And self-compiled programs were used to complete the hydraulic design of the whole flow passage of the centrifugal pump.In comparison with the blade of refe-rence,the space bending and twisting characteristics of the designed blade are more obvious.Applying RANS（Reynolds averaged N-S） equations with a standard k-ε two-equation turbulence model,numerical simulation of the inner flow field of the two pumps was carried out and a comparison and analysis of the data of numerical simulation of two centrifugal pumps,which was obtained from 13 working condition points,inclusive of the designed conditions,was made.With the numerical results of inner flow of the design pump and model pump,applying BVF diagnostic method,the BVF distribution of suction surface and pressure surface of two pumps was analyzed.The results show that,in comparison with the centrifugal pump of reference,the designed centrifugal pump has higher head and efficiency in the range of lower flow rate,and the maximum efficiency can be increased by 5.3%;the BVF distribution of the designed pump is more even and smooth,with smaller peak values,which indicates that the BVF-based flow field diagnosis can help restrain the unfavorable flow and effectively improve the hydraulic performance of the centrifugal pump.
出处
《排灌机械工程学报》
EI
北大核心
2013年第6期479-483,489,共6页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家自然科学基金资助项目(50809075)
中国石油大学(北京)基金资助项目(KYJJ2012-04-11)
关键词
离心泵
二元理论
水力设计
数值模拟
边界涡量流诊断
centrifugal pump
two-dimensional flow theory
hydraulic design
numerical simulation
boundary vorticity flux diagnosis
