Abstract: As the compressed air source for aircraft Environment Control System(ECS) and Main Engine Start(MES) system, the widely used Auxiliary Power Unit (APU) with load compressor in structure was researched. Firstly, the structural characteristics and air bleeding regulation were introduced and then how the load compressor works on APU was analyzed. The load compressor surge control method and APU common balance equations were discussed in detail. Based on components modeling, the mathematic model of APU was established. Finally, simulation results are compared with the bed test data. The results show that the simulation error is less than 3%.The mathematic model of APU is suitable for engineering application. 

Key words: Auxiliary power unit； Load compressor；Air bleeding characteristics calculation；Model and numerical simulation

摘要： 作为飞机环控系统与主发动机起动的气源,以目前广泛应用的带负载压气机结构APU(Auxiliary Power Unit)为研究对象,进行引气特性计算模型与计算方法研究。首先介绍了APU结构与引气工作特点,然后分析了建模时喘振控制阀SCV(Surge Control Valve)控制方法与APU共同工作机理,最后采用部件法建立了该类型APU引气计算数学模型。以某型APU为对象进行数值仿真并与实际试车数据比较,计算误差小于3%,表明所采用的建模方法是正确的,所建立的模型能够满足工程需求。 

关键词: 辅助动力装置;负载压气机;引气特性计算;模型与仿真 