某带分流叶片的亚声速离心压气机叶轮CFD结果确认及分析

为了研究数值模拟结果的准确性,使用计算流体动力学(CFD)软件Numeca,采用Spalart-Allmaras(S-A)模型和shear stress transport(SST)模型对某压比为1.5的亚声速离心压气机叶轮的性能进行了计算,并将4个不同截面上的速度分布等计算结果和实验数据进行了对比.结果表明:S-A模型和SST模型的计算结果几乎完全相同,误差小于1%;整体性能的模拟计算结果和实验值吻合较好,在设计工况点,误差在2%以内,在非设计工况点,误差也小于6%;不同截面上速度分布的计算结果和实验值相差较大,在轮毂附近,最大误差在20%左右,在轮缘附近,部分截面最大误差高于100%,不能真实反映轮缘附近的流动情况. 

CFD result validation and analysis of a subsonic centrifugal compressor impeller with splitter blades

A subsonic centrifugal compressor impeller with splitter blades of 1.5 pressure ratio was analyzed by CFD software of Numeca using Spalart-Allmaras(S-A) and shear stress transport(SST) models to study the accuracy of numerical simulation results. The measured results of the impeller and verifications of CFD at four sections were presented with respect to the velocity distribution, etc. Results show that the simulation results of S-A and SST models are almost the same, with the difference less than 1%; In general, the numerical simulation agrees well with the experiment, the difference is less than 2% at design point and 6% in off-design condition. The difference of numerical simulation and experiment results of velocity distribution is large in different cross sections. There are relatively big differences about 20% near hub and more than 100% near shroud, which can not truly reflect the flow condition near the shroud.