Thermoelastic Modeling of Layered Composites Considering Bending and Shearing Effects

Abstract

Composite materials and structures often exhibit thermal stresses and deformations due to their thermal expansion mismatch. For a layered laminate, the stress transfer mechanism involves both bending and interfacial shearing, which have been evaluated by Stoney’s equation and shear lag models, respectively. However, the two theories cannot consider both effects simultaneously due to their distinct assumptions. Because bending and shearing effects coexist in the physical problem, higher accuracy and fidelity can be achieved by considering both mechanisms. This paper presents an analytical formulation to solve this boundary value problem by constructing two separate trial functions from Navier’s equation. The analytical solution was proposed with an assumption of a perfectly bonded interface, and the corresponding coefficients were determined with the principle of stationary potential energy. The proposed model was applied to thermomechanical analysis of thin-film photovoltaic cells on smart window blinds, and good agreement was achieved between the theoretical prediction and finite-element results. A parametric study was also conducted to guide the design of solar window blinds and general bilayered composites.