THERMAL CONDUCTIVITY MEASUREMENTS OF FIBROUS INSULATIONS UP TO 2500°F
Efficient passive thermal protection system requirements guided the selection of three fibrous insulation materials for evaluation of heat transport properties. Measurements were made of their total or effective thermal conductivity and an analysis was conducted to determine the relative contributions from gaseous, solid conduction and radiation. In support of this analysis, thermal conductivity measurements were made in air from 950° to 2500°F, in argon from 300° to 2000°F and in vacuum from cryogenic temperatures to 2000°F. Limited descriptions are given of the guarded hot plate apparatus, sample configuration and instrumentation required to perform these measurements.