Published online by Cambridge University Press: 31 January 2011
Long duration storage of large quantities of cryogenic fluids for propulsion, power, and life-support is an essential requirement for missions into space. Efficient and reliable insulation materials are key to the success of these missions. The required insulation material must outperform the current standard multi-layer insulation (MLI) for thermal insulation and provide additional features such as durability, micrometeoroid orbital debris protection, and flexibility, all in one single-layer material. Ultra-low density and highly hydrophobic fiber reinforced aerogel material integrated with MLI has the potential to offer a great insulation package which will overcome several issues that the current standard MLI alone suffers from such as: 1) damage during installation, 2) high cost, and 3) degradation over time. The hybrid aerogel/MLI solution affords a more reliable alternative because it is robust, and will outperform the MLI in cases of vacuum loss. Low density and highly resilient methylsilicate aerogel will contribute less solid conductivity to the overall heat transfer within the aerogel/MLI system. Sol-gel optimization of low density and low dust methylsilicate aerogels will be presented. Thermal performance of two prototypes of hybrid aerogel/MLI composites and a baseline MLI system (1 inch thick, 90 layers) fabricated by Aerospace Fabrication and Materials (AFM) and tested at cryogenic temperatures under different vacuum level conditions (at Cryogenic Laboratory, NASA KSC) will also be presented.