Study On Aerodynamic Characteristics And Ballistic Characteristics Of Morphing Missiles

Modern warfare requires an increasing missile’s operational capability,which needs to achieve efficient aerodynamics and flight control while flying long distances,thus successfully completing flight and precision strike missions.Morphing missile has its unique advantages in self-adaptive control of aerodynamic environment and flight control.Therefore,this paper mainly focuses on the aerodynamic characteristics and ballistic characteristics of morphing missile,which provide experience and basis for the aerodynamic design,ballistic planning and variant strategies of morphing missile.First,with deflectable nose missile as the research object,the aerodynamic and ballistic characteristics of the missile are analyzed via numerical simulation method.The external flow field of the deflectable nose missile under different operating conditions and the laws of the aerodynamic coefficients of the deflectable nose missile changing with the head declination angle,Mach number and angle of attack are analyzed.The simulation results show that when the deflectable nose missile is flying supersonic at zero angle of attack,the change of the angle of the deflectable nose can change the aerodynamic characteristics of the missile.Based on the aerodynamic data of the missile,the external ballistic equation of the missile was established,and the external ballistic characteristics of the deflectable nose missile under different working conditions were studied according to the ballistic equation.The results show that the missile can achieve a reasonable correction effect by adjusting the angle of deflectable nose in highaltitude flight.Therefore,the deflectable nose control mode can be used as an ideal execution mode of terminal trajectory correction.Second,with variable-sweep-wing missile as the research object,the aerodynamic flow field and aerodynamic characteristics of missile with different sweep angles under multiple working conditions are numerically simulated and analyzed;and the deformation and stress of the wing under flight conditions are studied via the fluid-structure coupling method.The results show that the maximum stress of the variable-sweep-wing missile is located at the leading edge of the wing root and the maximum deformation is located at the leading edge of the wing tip under supersonic conditions;Based on the aerodynamic data,the ballistic characteristics of the variable-sweep-wing missile,the effect of the variation of the sweep angle on the flight range of the missile was studied and explored.According to the research results,the variable-sweepwing control method of the missile can slow the formation of shockwave drag,effectively improve the aerodynamic characteristics of the missile,thereby increasing its range.Thirdly,aerodynamic parameter response surfaces are constructed for deflectable nose and variable-sweep-wing missiles respectively.On this basis,a global optimization of the aerodynamic coefficient of the missile and its corresponding variant strategy is carried out with the lift-drag ratio as the constraint condition and the genetic algorithm as the optimization algorithm.The results show that the deflectable nose missile has a high lift-drag ratio with zero head deflection angle under supersonic conditions,while the variable-sweep-wing missile can obtain good aerodynamic characteristics at both subsonic and supersonic speeds by changing the angle of the sweep-wing.The specific performance is that in the subsonic stage,the lift coefficient of the fully deployed sweep-wing is 76% higher than that of the fully retracted wing;while in the supersonic stage,the sweep angle is gradually increased in combination with the working conditions,and the drag coefficient of the fully retracted sweep-wing is 53% lower than that of the fully deployed wing.