An innovative lightweight concept achieving improved thermal control and near isothermal operation for Space-Based Radar antenna systems is proposed. A totally passive thermal control approach controls the wide temperature variations experienced during orbit transit between daylight and eclipse periods and radar electronic power-on and off operation. The concept significantly improves operation of the temperature sensitive electronic components and reduces dimensional distortion of the antenna phased-array aperture. The thermal control concept utilizes a phase change material (PCM), which exploits its large latent heat capacity to effectively store thermal energy during the daylight/electronic power-on periods and extract heat during the eclipse/power-off periods to maintain the antenna structure temperature and protect the electronic components during the cold soak. The concept has several innovative features to enhance the thermal control of the antenna structure including: high thermal conductivity Gr/epoxy face sheets (for improved thermal spreading); high latent heat capacity phase change material (contained integrally within the antenna structure); and an ultra-low density/high thermal conductivity carbon foam core (for enhanced thermal transport between the PCM and antenna structure). The overall design concept provides a mass efficient and highly effective thermal control approach that requires no additional parasitic power demands.
Benefits: The passive thermal control concept will have immediate applications for SBR systems, as well as other space electronic power components. High payoffs include improved overall system performance in the form of temperature control and near isothermal operation. The concept is thermally effective, mass efficient (meeting the projected areal density goals) and provides thermal control without additional parasitic power consumption.
