Influence of Porosity Distributions on the Thermal Snap Response of Functionally Graded Sandwich Solar Panels in Low Earth Orbit

Traditional satellite aluminum or solid laminates solar panels are susceptible to significant thermal distortion and thermal snap during rapid temperature fluctuations in orbit. For modern lightweight satellite architectures, a critical design constraint arises from the inherent risk of thermal snap phenomenon where high-aspect-ratio flexible structures undergo dynamic instabilities due to rapid transitions in heat flux.
This study investigates the transient dynamic response of solar panels utilizing novel functionally graded material (FGM) sandwich plates featuring porous face sheets and a low-expansion ceramic core. The structural model is formulated using a Refined Shear Deformation Theory (RSDT) to capture accurate cross-sectional behavior and transverse shear effects without the need for shear correction factors. To evaluate the coupling between material topology and vibration, three distinct porosity distribution models namely even, uneven, and linear-uneven are incorporated into the FGM face sheets. The governing equations of motion are derived via Hamilton’s principle. The thermal environment is modeled as a comprehensive transient field, incorporating direct solar flux, Earth albedo, and Earth-emitted infrared radiation to ensure high-fidelity temperature gradients across the Low Earth Orbit (LEO) orbital period. A parametric study evaluates the influence of porosity coefficients, power-law volume fraction (n), and plate aspect ratios on the panel’s natural frequencies and thermally induced tip displacement. By tailoring the porosity distribution, a superior trade-off is achieved between thermal gradient dissipation and structural stiffness. The findings suggest that FGM sandwich structures represent a viable next-generation material platform for lightweight, thermally stable SmallSat components subjected to extreme orbital loading.