关键词: 充气机翼, 褶皱, 变刚度, 静气弹, 失稳

Abstract:

Based on classical engineering beam theory, combined with the stress state analysis of tense membrane, the wrinkling and instability criterions of inflated wing are proposed. We consider stiffness degradation caused by wrinkle of inflated wing, and treat the inflated wing as a beam which possesses a variable section stiffness with the expansion of wrinkle; an equivalent beam model of inflated wing is established, and the differential quadrature method is applied to calculate the bending deformation of inflated wing. The calculated results are consistent with the experimental results from the static bending tests of inflated wing, and hence verify the effectiveness of the proposed deformation analysis method of inflated wing. We use the strip theory to introduce the aerodynamic model which is then coupled with the equivalent beam model of inflated wing, and thus a static aeroelastic model of inflated wing is developed, which applies an iterative method to solve. According to the wrinkling and instability criterions, we use the proposed model to calculate the critical wrinkle dynamic pressure and critical instability dynamic pressure of the experimental inflated wing, and the obtained results are consistent with the results from tunnel tests. Furthermore, the proposed model is used to predict the extending process of membrane wrinkled zone and bending failure load for the inflated wing, and then obtain the available static aeroelastic envelope curves of inflated wing under different criterion conditions, and provide necessary safety boundary analysis for the design of inflated wing.

Key words: inflated wing, wrinkle, variable stiffness, static aeroelasticity, instablility