Stochastic imperfections method of stability analysis on metal stiffened panel under compression load
LI Fengming;TANG Gan;TONG Mingbo;Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle,Nanjing University of Aeronautics and Astronautics;College of Aerospace Engineering,Nanjing University of Aeronautics and Astronautics;
To make more reliable and stable analysis on the stability of metal stiffened panel,the stochastic initial geometric imperfections are introduced into the analysis,the finite element analysis on metal stiffened panel stability under compression load is performed by consistent imperfections method using ANSYS,the advantages and disadvantages of the consistent imperfections method are summarized,and a stochastic imperfections method is proposed considering initial geometric imperfections of stiffened panel and a test is carried out. The results show that,the consistent imperfections method plays a guide role in nonlinear deformation analysis,which makes the nonlinear deformation to develop toward the direction of eigenvalue buckling modes; the initial imperfections of the structure is random in the stochastic imperfections method and its size and distribution can not be predicted,and therefore the stochastic imperfections method can reflect the real performance of stiffened panel better. An automatic modeling program and an automatic analysis program for stochastic imperfections of stiffened panel are developed,which greatly improve the analysis efficiency and make the stochastic imperfections method possible for design.