叶顶间隙对离心压气机性能的影响机理研究  

Investigation on influence mechanism of tip clearance on centrifugal compressor performance

作　　者：甘新海 王超 刘佳敏 崔文豪 冯建军[2] GAN Xinhai;WANG Chao;LIU Jiamin;CUI Wenhao;FENG Jianjun(Xinxiang Aviation Industry(Group)Co.,Ltd.,AVIC,Xinxiang 453000,China;Institute of Water Resources and Hydro-Electric Engineering,Xi'an University of Technology,Xi'an 710048,China)

机构地区：[1]中国航空工业集团有限公司新乡航空工业(集团)有限公司,河南新乡453000 [2]西安理工大学水利水电学院,陕西西安710048

出　　处：《机电工程》2024年第7期1293-1300,共8页Journal of Mechanical & Electrical Engineering

基　　金：国家自然科学基金资助项目(52079108)。

摘　　要：为明确叶顶间隙对离心压气机性能影响的机理,采用数值模拟方法对不同叶顶间隙尺寸下的离心压气机叶顶泄漏涡和流动损失进行了研究。首先,对实验结果与数值计算结果进行了对比,验证了数值模拟的可靠性;然后,分析了不同叶顶间隙下压气机等熵效率及压比的变化趋势;最后,对内部流动特性进行了分析,阐述了不同间隙下叶轮内部涡结构变化形态、泄漏流流线分布及沿流动方向的熵变化规律,揭示了不同叶顶间隙对压气机性能的影响机理。研究结果表明:叶顶间隙比从0.018增加到0.054时,全工况范围内效率下降最大变化量分别为0.7%、0.6%、0.4%及0.2%,压比整体下降幅度保持在0.3%左右。叶顶泄漏流与主流掺混形成叶顶泄漏涡和叶顶分离涡,其中叶顶泄漏涡是主要损失来源。随着叶顶间隙比增大,靠近叶片前缘20%流向范围内的流动损失变化较小,靠近叶片尾缘40%范围内的损失增大。叶顶间隙比增加导致泄漏涡尺寸增大从而降低有效过流面积,是造成压气机性能下降的主要原因。To clarify the mechanism of the influence of tip clearance on the performance of centrifugal compressors,numerical simulation methods were used to study the effects of leakage vortices and flow losses at the centrifugal compressors under different tip clearances.Firstly,the reliability of the simulation was verified by comparing the experimental results with the numerical calculation results.Then,the changing trends of isentropic efficiency and pressure ratio of the compressor under different tip clearances were analyzed.Finally,the internal flow characteristics were analyzed,and under different clearances,the changes in the vortex structure inside the impeller,the distribution of leakage flow streamlines,and the entropy change law along the flow direction were elaborated.The mechanism of different tip clearances'effect on compressor performance was investigated.The research results indicate that when the tip clearance ratio increases from 0.018 to 0.054,the maximum changes in efficiency decrease across the entire operating range are 0.7%,0.6%,0.4%,and 0.2%respectively.The overall decrease in pressure ratio remains around 0.3%.The tip leakage flow is mixed with the mainstream to form tip leakage vortices and tip separation vortices,among which tip leakage vortices are the main source of loss.As the tip clearance ratio increases,the flow loss within the 20%flow direction range near the leading edge of the blade changes less,while the loss increases within the 40%range near the trailing edge of the blade.The increase in the tip clearance ratio leads to an increase in the size of the leakage vortex,thereby reducing the effective flow area,which is the main reason for the performance degradation of the compressor.

关 键 词：气体压缩机 离心压气机 熵变化规律 数值模拟方法 压缩机气动性能 泄漏涡 流动损失 内部流动特性 

分 类 号：TH452[机械工程—机械制造及自动化]