喘振发生前车用涡轮增压器离心压气机非稳态流动分析

摘要

Study on the phenomenon and mechanism of surge is an important topic in turbocharging field.The unsteady simulation of the JP60 centrifugal compressor at the position before the highest pressure ratio, the position near the highest pressure ratio, the position behind the highest pressure ratio and the position near surge at 120 000 r/min are conducted. The phenomenon of unsteady flow in different parts of the compressor is analyzed. The influence of the trailing edge backfiow vortex to leakage vortex and leading edge vortex is mainly analyzed. The influence of the trailing edge vortex on the deterioration of compressor and its formation mechanism are clarified. It lays the foundation for further study to surge phenomenon.%喘振现象及其机理的研究一直是涡轮增压领域重要的课题,对JP60离心压气机在120000r/min最高压比点前、最高压比点附近、最高压比点后和临近喘振点附近4个工况点进行了非稳态模拟计算,并对压气机各部件的非定常流动现象分别进行了分析,重点分析了叶轮尾缘回流涡随流量减小对叶尖泄漏涡和前缘涡的影响,明确了尾缘回流涡形成及其对压气机性能恶化影响的流动机理,从而为进一步深入研究喘振现象奠定基础.