Aeroservoealstic Analysis And Experiment Of MIMO Wings With Geometrically Nonlinear Wings

The analysis of aero-servo-elastic system under geometric non-linear effect is the current difficulty and hotspot for aircraft aeroelastic research.With more and more applications of aircraft composite materials,and the pursuit of high lift-to-drag ratio,the wing is developing towards a large aspect ratio wing.In this way,the aeroelasticity of the wing is becoming more and more serious,and it may even cause geometry Non-linear problems.At present,researchers have done a lot of work on the problem of geometric nonlinear aeroelasticity,and have solved a large number of problems.But at present,there are not many people who have studied the problem of aerodynamics caused by the deflection of the rudder surface at low speeds due to the geometric nonlinearity of the wing.First,facing the low-speed wind tunnel,design a large flexible large aspect ratio wing with two rudder surfaces,and complete the finite element modeling.The geometric nonlinear problem is disassembled into aeroelastic statics to solve the nonlinear equilibrium position of the model,and the solution is linearized at the nonlinear position.By changing the angle of attack,the deflection angle of the rudder surface and the wind speed,a three-dimensional element model for geometric nonlinear analysis is determined.And do open-loop stability flutter analysis to determine the flutter speed.Secondly,the unsteady aerodynamic modeling calculation of the three-dimensional metamodel and the aerodynamic rational function fitting of the frequency domain aerodynamics are performed to facilitate the establishment of the time domain control system model.At the same time,the design of the stability-increasing control loop is completed,and the The wing's singleinput single-output system modeling work establishes a frequency domain control system model and performs stability analysis through frequency domain stability criteria.Thirdly,the stability analysis of the multi-input multi-output control system model of the wing,the rational function fitting of the unsteady aerodynamic results of the wing model,the aerodynamic force on the virtual axis is extended to the entire complex domain,and from the structure The dynamic equation is deduced to establish the analysis model of the time-domain control system,and the closed-loop feedback loop is designed.Subsequently,the minimum singular value theory is applied to the model to obtain the time-domain stability results of the model.Finally,the wind tunnel blowing model is made according to the finite element design,and the ground tunnel model is tested on the ground.Due to the impact of the epidemic,the follow-up wind tunnel test cannot be done in this article,and the follow-up test will be supplemented in the future learning phase.In this paper,an analysis platform for aero-servo elastic wing system is completed.On this basis,the model can be used for gust load reduction and geometric nonlinear flutter suppression.