Aerodynamic Characteristics Of Transonic Wing With Variable Curvature And Its Structural Design

The deformable intelligent vehicle has become the research hotspot at home and abroad,through the intelligent deformation technology,the aircraft shape parameters are changed so that the aircraft can maintain the best flight parameters during the flight and improve the flight performance of the aircraft.In the course of airplane flight,changing the camber of the wing front and rear edge has the most influence on the aerodynamic performance of the aircraft,especially in the transonic flight,the slight variation of the curvature of the front and rear edges will have a great influence on the aerodynamic characteristics of the wing.Therefore,in the transonic flight,the purpose of seamless continuous smooth change of the wing camber,can improve the wing in transonic flight resistance divergence characteristics,shock stall characteristics,increase the wing lift resistance ratio,improve the aircraft cruise Mach number.In this paper,the transonic aerodynamic characteristics of the trailing edge are studied,and the mechanism design and kinematics simulation are carried out for the trailing edge camber.First of all,this paper takes the supercritical airfoil DFVLR R-4 airfoil as the basic airfoil,at the leading edge of the 30% chord,the airfoil is positively(downward)deflected 10,20 and negative(upward)deflection 10,20,to obtain four kinds of variable camber airfoil,the trailing edge 30% chord strength,the trailing edge camber downward respectively deflection10,20,30,3 types of deformable airfoils were obtained.Secondly,based on aerodynamics and computational fluid dynamics,the transonic aerodynamic characteristics of the airfoil are analyzed.Finally,the structure of the trailing edge variable curvature wing is designed and the kinematics simulation is carried out.A textual study draws the following conclusions:(1)In transonic,the forward deflection resistance divergence of the airfoil leading edge curvature is improved,the negative deflection resistance divergence is worse,the airfoilpositive deflection lift coefficient decreases with the same flow Mach number,the negative deflection,the lift coefficient increases,and the stall angle of attack characteristic is improved when the airfoil is positively deflected.It is found that the leading edge variable curvature airfoil can be applied to transonic.(2)in transonic,the curvature of the rear edge of the supercritical airfoil is changed downwards,the airfoil’s critical Mach number is advanced,and the resistance divergence is worse,but the lift coefficient increases and the lift-drag ratio increases before the shock stall,the airfoil change is at 10 o’clock,the aerodynamic characteristics in transonic are better,and the airfoil lift coefficient is increased by 21.12%,The lift-drag ratio was increased by 9.2%,and the stall angle of the airfoil was improved with the curvature of the trailing edge increasing.(3)After the motion simulation analysis of the variable curvature wing structure,the variable curvature mechanism can basically realize the continuous deformation of the trailing edge of the wing in the Transonic cruise on the basis of the large deflection angle of the plane take-off and landing trailing edge.