基于 CFD 和推阻分解技术的全机溢流阻力预测与分析

摘要

During the flight,the mass flow through the engine is controlled according to flight mission requirements.The pressure distribution on the nacelle lip will change significantly, as well as the total force of the outflow acting on the inner stream tube ahead of the intake,con-sequently,the spillage drag will be changed.The spillage drag for a civil aircraft at different mass flow is obtained through the combined method of CFD powered simulation and thrust-drag bookkeeping.Decisive issues to determine the spillage drag,such as the mass flow rate,flight Mach number,altitude and angle of attack,are analyzed.The prediction method and the investi-gation findings of the spillage drag can be referenced in aircraft/turbo-fan engine integration design,as well as the high-bypass-ratio nacelle design and related aerodynamic predictions.%飞机在飞行过程中，根据性能需求，需要不断调整发动机活门流量系数，因此发动机短舱唇口的压力分布形态会发生很大变化，前方外流作用于进气道内流管上的合力也将改变，从而引起溢流阻力变化。本文基于某型号飞机，结合 CFD 动力模拟和推阻分解方法，获得不同流量系数下的溢流阻力，并分析流量系数、马赫数、高度、迎角对溢流阻力的影响。溢流阻力预测方法和影响研究可为飞机/涡扇发动机一体化设计、大涵道比短舱设计和气动力预测提供参考。