气动参数对闭环飞机短周期模态特性的影响

摘要

现代高性能战斗机均采用放宽静稳定性的布局构型,需通过先进飞行控制的设计来保证其闭环飞机在全飞行包线内均具有优良的动态特性.受到舵面操纵特性的限制,飞行控制系统(FCS)的能力是有限的,即飞机本体的气动参数需满足一定的要求才能保证闭环系统的飞行品质.本文建立了研究本体气动参数对闭环飞机短周期模态特性影响规律的方法,采用等效参数准则,以基于模型参考动态逆控制律的某放宽静稳定飞机为算例,计算分析了不同本体气动参数取值大小对闭环飞机短周期模态特性的影响规律.结果表明,升降舵操纵效能是影响闭环飞机短周期模态特性的主要因素,本体气动参数需满足一定的适配关系才能保证闭环飞机具有优良的短周期飞行品质.研究方法和结果对于放宽静稳定性飞机的本体设计与飞行控制系统设计等都具有很好的参考价值.%Owing to the relaxed static stability technology applied to the modern high-performance fighter aircraft,the design of an advanced flight control system is required to confirm its closed-loop system for an excellent dynamic property within the flight envelope.The ability of flight control system(FCS)is limited as a result of the control effectiveness and deflection rate of the control surface.The designed aerodynamic param-eters of aircraft must meet certain requirements to confirm good flying qualities in its closed-loop system.This paper presents a new method which describes the influence of various aerodynamic parameters on short -period mode characteristics of closed-loop aircraft.A relaxed static stability aircraft with model reference dynamic in-version control law is provided to investigate the influence rules of various aerodynamic parameters on short -pe-riod mode characteristics based on the equivalent parameter criterion.The results show that the elevator control effectiveness has a great influence on the short-period mode characteristics and the aerodynamic parameters need to match a certain match value set to keep excellent short-period mode flying qualities.The proposed method can provide reference for flight control system design with the optimized aerodynamic parameters for re -laxed static stability aircraft.