High-order multiscale modeling for the thermo-elastic analysis of large-scale phased array antennas

In recent years, increasing attention has been focused on Space Solar Power Systems (SSPSs) as a promising solution for generating large-scale clean energy. Despite their potential, SSPSs remain in the development stage, facing significant challenges before they can be deployed practically. A critical issue lies in integrating ultra-lightweight planar antenna structures with dense dielectric patches, where thermal deformations from mismatched Coefficients of Thermal Expansion (CTEs) can compromise electromagnetic performance. Structural analysis of these deformations, caused by extreme temperature variations, is therefore essential. The present work proposes a homogenization procedure to evaluate thermo-elastic effective properties, followed by localization analysis of stress and strain fields at the patch–antenna interface within a multiscale framework. This ensures accurate deformation predictions while reducing computational costs compared to full antenna simulations. The micromechanical analysis relies on the Mechanics of Structure Genome (MSG), which decouples global and local behaviors, provides constitutive relations, and details local field distributions. Using the Variational Asymptotic Method (VAM), MSG determines effective thermo-elastic properties through a reduced-order formulation dependent only on material and geometry, eliminating explicit load applications and improving efficiency. The structural model utilizes high-order beam finite elements from the Carrera Unified Formulation (CUF), which are aligned with the patch axis to represent the antenna’s Representative Volume Element (RVE). Legendre polynomials describe the refined beam model’s cross-section, achieving accuracy comparable to that of solid finite element models with significantly lower computational costs. The CUF framework thus combines efficiency with high fidelity. Overall, the methodology offers a robust tool for analyzing large-scale phased array antennas, facilitating their design through accurate yet efficient predictions of thermo-elastic behavior. The proposed multiscale approach is validated against experimental data, confirming its reliability and applicability to real-world scenarios.