Sprayable Thermal Insulation for Cryogenic Tanks

The Sprayable Thermal Insulation for Cryogenic Tanks (STICT) is a thermal management system applied by either an automated or manual spraying process with less sensitivity to process chemistry and environmental parameters than current spray-on foam insulations (SOFI) like BX-265, while providing better insulation performance. The sprayable insulation based on aerogel forms an aerodynamically smooth, uniform coating with better cohesion and lower thermal conductivity. Aerogel sprayed insulation has shown in Phase I better thermal performance than polyurethane spray-on foam insulation at similar or lower areal densities. Application of thinner layers of insulation combined with greater material resistance to cracking and debonding will eliminate the generation of in-flight debris. Minimization of volatile gas blowing agents and organic components will reduce gas expansion through intracellular pressures and reduces the risk posed by shedding events during ascent. The proposed sprayable insulation can render future space transportation systems safer and more reliable. Addressing lower temperature requirements of the thermal protection system, lightweight hybrid aerogel sprayable compositions will be developed. Hybrid aerogels with various dopants will be synthesized for better compatibility with the binders or organic foams. For the most stringent thermal and mechanical loads silica aerogel– silica foams will be developed as sprayable insulation.