离心压气机宽无叶扩压器旋转失速的数值研究

无叶扩压器作为离心压气机的重要部件,研究其内部旋转失速的诱发过程及机理对离心压气机无叶扩压器旋转失速的主动控制具有重要意义。利用ANSYS平台对离心压气机建模并对其旋转失速过程进行非稳态数值模拟。结果表明:离心压气机无叶扩压器旋转失速是随着流量的逐渐减小建立起来的,失速工况点位于性能曲线的负斜率区;无叶扩压器内部,低速区靠近扩压器盖侧,高速区靠近扩压器盘侧;宽无叶扩压器的旋转失速与扩压器出口回流区有关,出口处回流区逐渐向扩压器内部发展,导致核心流发生畸变,最终导致旋转失速的发生。

Numerical Investigation of Rotating Stall in Centrifugal Compressorwith Wide Vaneless Diffuser

As an important part of the centrifugal compressor,it is of great significance to study the induced process and mechanism of the rotating stall in vaneless diffuser.In this paper,the model of centrifugal compressor is established by using ANSYS platformand the unsteady numerical simulation of its rotating stall process is conducted.The results show that the rotating stall of vaneless diffuser is established with the decrease of flow rate,and the stall point is located in the negative slope of performance curve.The low speed area is close to the shroud of diffuser and the high speed area is close to the hub of diffuser.The reflux area at the outlet is associated with the occurrence of rotating stall.The internal development of reflux leads to the distortion of the core flow,which eventually leads to the occurrence of rotating stall.