耦合三维CFD的多级压气机气动扩稳预测模型研究

Aerodynamic Stability Expansion Prediction Model of Multistage Compressors Coupled with Three-Dimensional CFD

关键词:  多级压气机  喘振边界  单元体模型  级特性  气动扩稳

Key words:  Multistage compressor  Surge boundary  Disk-lag-volume unit model  Stage characteristics  Aerodynamic stability expansion

摘要:

为将扩稳措施对压气机级局部流场的扰动与多级压气机喘振边界相关联，准确预测各种扩稳措施对多级压气机喘振边界的影响，基于三维CFD数值模拟技术对包含扩稳措施的压气机级特性的预测方法与基于“激盘-滞后-集聚容积”一维单元体稳定性预测模型进行耦合，建立了多级压气机气动扩稳数值模拟的预测模型，实现了对多级压气机喘振边界和扩稳效果的预测。应用发展的预测模型，对某三级轴流压气机在叶尖微射流作用下的喘振边界进行了预测分析，证明了本文预测模型的可靠性和有效性。预测结果表明，在压气机转子叶尖前缘的微射流，能够明显提高压气机的效率，并提高压气机级的稳定裕度。数值模拟结果同时揭示了多级压气机中不同级和不同位置扩稳对多级压气机喘振边界具有明显不同的影响，某型压气机第三级转子叶尖微射流扩稳设计能够有效提高压气机的稳定性。

Abstract:

In order to associate the local flow field change caused by various extended stability methods with the surge boundary of multistage compressor， and accurately predict the impact of extended stability means on the surge boundary of multistage compressor， a prediction method of compressor stage characteristics including extended stability means based on three-dimensional CFD simulation technology is coupled with the one-dimensional "disk-lag-volume" unit model， and a prediction method is established to predict the surge boundary and stability expansion of multistage compressor. Using the prediction model developed in this paper， the surge boundary of a three-stage compressor with the tip micro-jet is predicted and analyzed， which proves the reliability and effectiveness of the present model. The predicted results show that the micro-jet at the leading edge of the compressor rotor tip can significantly improve the efficiency and the margin of the compressor stage. The numerical results also reveal that the stability expansions at different positions and different stages in the multistage compressor have significantly different effects on the surge boundary of the multistage compressor. The micro-jet on the third stage rotor tip can effectively expand the stability of the multistage compressor.