Experimental Studies on Shadow Shields for Thermal Protection of Cryogenic Tanks in Space

Book excerpt: Experiments were performed on multiple flat-disk shadow shields to determine the effects of shield spacing number, emissivity, lateral conductance, and targeting (high-emissivity coatings on annular rings of shields) on thermal performance. The experimental data, in general, agreed closely with an analytical model which assumed diffuse surfaces with nonuniform radiosity. A shadow-shield system for a hypothetical space vehicle was designed, scaled down, and tested. Results demonstrated: (1) a lightweight method of shield construction; (2) shield-support interactions: and (3) reduction of support heat leaks by shield location, attachment methods, and the use of high-emissivity coatings.