离心压气机叶轮出口气体流动演变规律数值仿真研究

Numerical Simulation on Gas Flow Characteristics of Centrifugal Compressor Impeller Exit

采用全三维仿真计算方法,针对离心压气机叶轮出口位置,进行了气体流动演变规律研究。研究结果表明:相同转速下,随着流量的减小,叶轮出口绝对气流角增加,且增加的范围主要集中在叶轮流道中心以下区域,叶顶区域变化不明显;相同转速下,叶轮出口总压比呈逐渐增加趋势;相同转速下,流量的减小使得叶轮顶部的效率损失减小而主流区的效率损失增加,压气机的最终效率取决于间隙流和主流流动损失的耦合作用。

Three dimensional simulation of gas flow characteristics at the centrifugal compressor impeller exit was conducted.The results show that the impeller outlet absolute flow angle increases with the decrease of mass flow rate at the same rotating speed and the increase inclination occurs mainly in the area below the center of impeller flow passage and less in blade tip area.In addition,the total pressure ratio shows the increase trend and the efficiency loss decreases at blade tip and increases in main flow zone due to the decrease of mass flow rate.The final efficiency of compressor depends on the coupling effect of tip clearance flow and main flow.