Application Of The Variation Method To The Primary Study Of Aeroelasticity

The aeroelastic problem is as old as aircraft. With improvement of aircraftperformance, the aeroelastic problem becomes serious, so the aeroelastic analysis becomes more and more important. In the past wind tunnel investigations were the mainway to study the aeroelastic problem. With the immense leap incomputational speeds in the recentpast, numerical experimentsvia Computational Fluid Dynamics are fast maturing as a viable complement. The investigation on the aeroelasticity theoryisthe base of the numerical experiment. So it becomes more and more important. This paper attempt to study the problems of the aeroelasticity of the aircraft via variational principles and use it to the actual structure. The main contents of this paper are as follows:1.Considering the effect of curve, the principle of minimum complementory energy is applied to deduce the formulas of shearing flow on section of multi-cell and the stiffness center in this thesis. Meanwhile, the author takes the section of tri-cell of shearing flow of section of tri-cell and the value of the stiffness center. Obtain the divergence of missile wing and deduce the angle and divergence critical speed, when the section of tri-cell makes a free torsion.2.Establish the complementary Hamiton theory which is applicable to the thin-wall structure. Transformation of naught addition is applied to deduce the theory stationary condition of quai-complementary Hamiton. And Obtain the formula of the critical velocity pressure of flutter.