Dynamic mesh method based on diffusion equation and nodal rotation for high-aspect-ratio composite wings

Abstract

In this paper a dynamic mesh method based on diffusion equation and nodal rotation is developed for high-aspect-ratio composite wings. Mesh displacement is described by diffusion equation and calculated by finite element method. The mesh was distorted because the displacement of the mesh nodes is uncoupled in different directions, and its quality diminished due to large deformation. The nodal rotational method is introduced to solve this problem. The technique used the same diffusion equation to describe the rotational angle and is solved by the finite element method. The node nearest the wall boundary is the rotational centre and the corresponding rotational vector is the rotational axis. The new position of the mesh node is obtained by rotating transformation. The mesh deformation of two-dimensional NACA0012 airfoil mesh, three-dimensional spherical mesh and high aspect ratio composite wings are verified for various cases. The results show that the present method is applicable to structural and unstructured/hybrid meshes. The mesh quality is improved and its overlap and negative volume are effectively prevented under large deformation.