0618877 - ÚPT 2025 RIV FR eng C - Conference Paper (international conference)
Frolec, Jiří - Králík, Tomáš - Krutil, Vojtěch
Impact of contamination of a metallic surface on its thermal absorptivity.
Refrigeration Science and Technology. In: Cryogenics 2023. The 17th IIR International Conference, Dresden, Germany, April 25-28, 2023. Proceedings. Paris: International Institute of Refrigeration, 2023, s. 59-64. ISBN 978-2-36215-053-1. ISSN 0151-1637.
[Cryogenics 2023. IIR International Conference /17./. Dresden (DE), 25.04.2023-28.04.2023]
Institutional support: RVO:68081731
Keywords : Heat Transfer * Thermal Radiation * Cryogenics * Contamination * Cryostat Design
OECD category: Thermodynamics
Result website:
https://iifiir.org/fr/fridoc/impact-de-la-contamination-d-une-surface-metallique-sur-son-147065DOI: https://doi.org/10.18462/iir.cryo.2023.0142

Very low absorptivity values of metallic surfaces, which are often used in cryogenic systems, help to reduce the heat load transferred by thermal radiation on their cold parts. Low absorptivity may be, however, enhanced by an undesirable contaminant. Using dedicated apparatus in our laboratory, we measured total hemispherical absorptivity of a thin layer of ice, a mineral oil used in vacuum pumps, two different vacuum greases and a powdery basanite material, each applied individually in comparable amounts (approx. 0.23 mg.cm(-2)) on an aluminium surface. The contaminated surface was then exposed to thermal radiation emitted by a source at temperatures ranging from 20 K up to 280 K. Compared to the bare aluminium surface, we observed a significant increase of the original absorptivity after the contamination process and in the case of the powdery material also a nonlinear response to increasing irradiation. Our findings may have practical relevance for the design and thermal management of spacecrafts as well as ground-based cryogenic systems.
Permanent Link: https://hdl.handle.net/11104/0365653