Stiffness matrix solution for shells of revolution possessing variable thickness heat protection

Abstract

A composite laminated torispherical shell was idealized as a network of curved beams. A stiffness matrix method was developed in torispherical coordinates which are amenable to the current family of manned spacecraft. The laminated shell was composed of an ablator, bond, 2 stainless steel face sheets, and a 2 inch thick stainless steel core. Thermal and mechanical loadings were considered. A structural model of the Apollo aft heat shield substructure was analyzed for a variety of thermal and mechanical loadings. A correlation was made of the analysis with test data and 2 independent digital computer analyses. An analysis of a hemisphere under hydrostatic loading was included to establish a link with "exact" theory. The development of the theory, transformations, Fortran programming effort, and substantiating data from the basis of the research. Selected stresses and displacements were used in comparisons to demonstrate the accuracy of the procedure.