Design and thermal–optical evaluation of an optical window module for a near-space remote sensor under ultra-high temperature conditions

Abstract

Under hypersonic flight conditions, the optical window external surface of a near-space remote sensing system generates a large thermal load due to aerodynamic friction, resulting in serious additional contact thermal stresses and deformation of the flat window. Consequently, the imaging performance of the optical remote sensing system (ORSS) is reduced. To overcome this issue, a flexible support combination structure (FSCS) for an optical window suitable for ultra-high temperature conditions was developed in this study, which ensures the optical imaging quality requirements of the system. Based on the external thermal environment characteristics of a hypersonic aircraft, an aerothermal simulation model of the aircraft with a window component was established. More importantly, the FSCS was optimized and a thermal–structural model of the window component was established, and the opto-mechanical-thermal analysis method was proposed for the ORSS. Finally, the thermal-optical properties of the deformed window were evaluated. The results show that the optimized window component satisfies the optical imaging design requirements, which guides engineers in ultra-high temperature thermal analysis and optical imaging.

Keywords

• Thermal deformation
• Thermal-optical evaluation
• Optical window
• Flexible support