Elastic Analysis of Anisotropic Rotating Sandwich Circular Ring With a Functionally Graded Transition Region

The elastic analysis of anisotropic rotating sandwich ring with a functionally graded transition region was carried out. Like the shell sandwich structure in nature, the ring is composed of 3 well-bonded regions, of which the inner and outer regions are made of homogeneous anisotropic materials, and the intermediate transition region is made of a material with arbitrary-gradient properties along the radial direction. Based on the boundary conditions and the continuity conditions at the interface, the 2nd Fredholm integral equation for the radial stress was obtained with the integral equation method, then the stress and displacement fields of the sandwich ring structure were obtained through numerical solution. The distributions of the stress and displacement fields in the sandwich ring structure were given. Different gradient changes encountered in engineering practice can be solved only through substitution of the corresponding function model. The effectiveness and accuracy of the integral equation method were verified through comparison of the numerical solutions with the exact ones for a special power function gradient variation form. The more general Voigt function model was adopted for the intermediate transition region, and the influences of the anisotropy degree, the gradient parameter, and the thickness on the stress and displacement fields were analyzed. The proposed Fredholm integral equation method provides a powerful tool for the optimal design of anisotropic functionally graded materials and sandwich ring structures. The numerical results make a theoretical guidance for the safety design of anisotropic functionally graded sandwich ring structures.