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VO2-based switchable radiator for spacecraft thermal control.

ABSTRACT: Direct calorimetric measurements of a solid state passive switchable radiator for spacecraft thermal control have been performed in a simulated space environment. Dynamic emissivity control is provided by the thermochromic phase change in a multilayer VO2 thin film based resonant absorber. The measured radiated power difference between 300?K and 373?K was 480?W/m2 corresponding to a 7× difference in radiative cooling power. We present theoretical and experimental radiator values for both normal and hemispherical as well the optical properties of VO2 as determined via infrared spectroscopic ellipsometry.

SUBMITTER: Kim H

PROVIDER: S-EPMC6683125 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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VO2-based switchable radiator for spacecraft thermal control.

Kim Heungsoo H Cheung Kwok K Auyeung Raymond C Y RCY Wilson Donald E DE Charipar Kristin M KM Piqué Alberto A Charipar Nicholas A NA

Scientific reports 20190805 1

Direct calorimetric measurements of a solid state passive switchable radiator for spacecraft thermal control have been performed in a simulated space environment. Dynamic emissivity control is provided by the thermochromic phase change in a multilayer VO2 thin film based resonant absorber. The measured radiated power difference between 300 K and 373 K was 480 W/m2 corresponding to a 7× difference in radiative cooling power. We present theoretical and experimental radiator v ...[more]

PMID: 31383877

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