Aerodynamic instability evolution of a multi-stage combined compressor  

作　　者：Jiaan LI Xinqian ZHENG 

机构地区：[1]School of Vehicle and Mobility,Tsinghua University,Beijing 100084,China

出　　处：《Chinese Journal of Aeronautics》2025年第1期286-296,共11页中国航空学报(英文版)

基　　金：supported by the National Science and Technology Major Project of China(Nos.2017-II-0004-0016 and J2019-I-0011-0011).

摘　　要：Unstable operating conditions such as surge could cause damage to both aerodynamic performance and structural integrity of a compression system.This paper addresses the critical issue of aerodynamic instability in compressor design,particularly focusing on an axial-centrifugal combined compressor,a widely used yet underexplored configuration.An experimental investigation was conducted on a three-stage axial and one-stage centrifugal compressor(3A1C),using two pipe systems and employing fast-responding transducers to capture the dynamic instability process from choke condition to deep surge.Results reveal that at the design speed,3A1C enters deep surge directly,whereas at off-design speeds,it experiences rotating stall and mild surge across a wide mass flow range.Some special instability features in the combined compressor can be found in the steady state map and dynamic process.The characteristic curve of the first axial stage keeps a positive slope during the whole mass flow range at an off-design speed.The first stage could work stably on the stall characteristic curve because the centrifugal stage has stronger pressurization and plays a dominant role in global aerodynamic instability.Besides,rotating instability occurs at the first rotor tip and disappears as the back pressure increases,which is also rarely seen in a single-axial compressor.This is also related to the strong pressurization of the centrifugal stage.The findings of this paper will contribute to the understanding of aerodynamic instabilities in combined compressors.

关 键 词：Aerodynamic stability Combined compressors SURGE Post-stall behaviors Transient process 

分 类 号：V231.3[航空宇航科学与技术—航空宇航推进理论与工程] TH45[机械工程—机械制造及自动化]