Thermo-optical comparison of all-borosilicate and borosilicate-acrylic hybrids for multi-pane space windows

Windows are critical components for maintaining the functionality of space stations in the demanding environment of Low Earth Orbit (LEO). This article considers borosilicate glass (BSG) as a compelling novel material for multi-pane fenestration, evaluating its potential to outperform traditional options like fused silica (FS). By specializing our previously-established methodological framework, we evaluate BSG in its capacity to provide greater radiation shielding than FS, in addition to its superior cost-to-performance ratio. Our analysis models the effects of electromagnetic waves on a three-pane window, analogous to that of the ISS Cupola, in hybrid configurations combining BSG and acrylic glass. We simulate the system’s response to solar and terrestrial radiation to assess its transient thermal state and optical properties under two extreme LEO scenarios, corresponding to maximum thermal cycling or peak heating. Beyond the specific parameters of this study, the collective material properties of BSG suggest a robust foundation for achieving superior performance for space glazing.