On the formulation of a finite element method for the stiffened multi-layered airfoil/hydrofoil structure: Post buckling analysis for the wings of underwater gliders

摘要

Highlights?The multi-layered stiffened airfoil/hydrofoil is studied.?Exact smooth configuration is obtained.?The high-order basis functions are very identical to mode shapes.?The mass matrix is diagonal.?The number of DOF is much smaller.AbstractA finite element method is developed for the stiffened multi-layered airfoil/hydrofoil structure for the large deformation and finite strain problem. The kinematics of the airfoil/hydrofoil is set up. The Consistent Orthogonal Basis Function Space is applied for the airfoil/hydrofoil structure. Given the airfoil/hydrofoil configuration and boundary conditions, the basis function space can be uniquely determined, such that the diagonal mass matrix is obtained accurately and the basis functions are very identical with the mode shape functions of the structure. In order to satisfy the displacement compatibility condition between adjacent layers of the airfoil/hydrofoil, the traction degree-of-freedom is also induced.The post buckling analysis is presented for the wing (hydrofoil) structure of the underwater glider. The water pressure is applied on the outer surface and the critical buckling pressure is calculated. The post buckling equilibrium path is also given. The results are verified with ANSYS. The present study of the buckling analysis of the airfoil/hydrofoil under water pressure is helpful to the design of underwater glider.]]>