Abstract: In order to obtain the large bypass ratio engine through flow nacelle(TFN) aerodynamic characteristics accurately， three-dimensional flow field of a trunk liner aircraft nacelle was numerically simulated according to the development requirements of civil jet aircraft， the flow field， aerodynamic characteristics and drag correction method of the TFN were analyzed. The results suggest that: The flow field and aerodynamic characteristic of TFN are similar to the large bypass ratio engine powered nacelle， but it is still necessary to correct the TFN aerodynamic characteristics including the internal drag due to the internal aerodynamic force accounting as thrust and TFN inability of simulating the engine inflow and jet effects. By analyzing the thrust and drag accounting theory of large bypass ratio engine， the method for decomposing the aerodynamic force on TFN is obtained and can be applied to the internal drag correction of the TFN. The aerodynamic characteristics of the TFN are closer to the real engine nacelle through correcting the spillage drag and internal drag， the difference between the TFN and real engine nacelle decrease about 46%. In the cruise condition， the TFN with drag-corrected can better reflect the real engine aerodynamic characteristics， but it is suggested to carry out further analysis on the impact of jet effects.

Key words: Civil aircraft；Engine；Nacelle；Drag；Numerical simulation

摘要： 为准确获取大涵道比发动机气动特性，根据民用飞机研制需求，对民用干线飞机的发动机短舱三维流场进行数值模拟，对比了通流短舱和真实发动机短舱流场特征，分析了通流短舱的气动特性和阻力修正方法。结果表明:大涵道比发动机通流短舱的流场特征、气动力和真实发动机较为接近，但是由于发动机内流通道气动力一般计入推力和无法完全模拟发动机进排气效应，有必要对通流短舱进行考虑内部阻力在内的气动特性修正；通过对大涵道比发动机推阻力划分理论进行分析，获得了与真实发动机一致的通流短舱气动力分解方法，并可以较好地应用到通流短舱内部阻力修正上；通过对通流短舱阻力修正(含内阻修正和溢流阻力修正)，在巡航状态下修正后的通流短舱与发动机动力短舱阻力特性差异降低了约46%；在高速巡航状态，阻力修正后的通流短舱气动特性可以更好地反映真实发动机工作的影响，但依然有必要对发动机动力喷流影响开展进一步的分析工作。

关键词: 民用飞机；发动机；短舱；阻力；数值模拟