Near field radiative heat transfer between macro-scale metallic surfaces at cryogenic temperatures

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F21%3A00549394" target="_blank" >RIV/68081731:_____/21:00549394 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0011227520301582" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0011227520301582</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.cryogenics.2020.103156" target="_blank" >10.1016/j.cryogenics.2020.103156</a>

Result language

angličtina

Original language name

Near field radiative heat transfer between macro-scale metallic surfaces at cryogenic temperatures

Original language description

Knowledge of radiative heat transfer between bodies at various temperatures is essential for efficient design of cryogenic devices. Radiative far-field heat transfer is commonly taken into account. Nevertheless, when the distance d between components of a device becomes small, smaller than the characteristic wavelength of Planck's far field thermal radiation, an additional heat transfer caused by thermal electromagnetic near-field starts to play a role. At cryogenic temperatures and micrometric distances, this near field heat transfer can exceed the far-field one by orders of magnitude. We report experimental results on near-field and far-field heat fluxes q transferred across a plane parallel vacuum gap d between pair of identical copper (RRR = 10) and tungsten (RRR = 1.5) samples. The heat flux q was measured over the distances d = 1–100 μm and for various temperatures T2 = 15–80 K of the hot sample and the temperature T1 down to 5 K of the cold one. We compare the copper and tungsten data with previously published results for normal metals Nb and NbN. For each pair of identical samples, the measured values of near-field thermal conductance of vacuum gap, KT = q/(T2 − T1), collapse into nearly a single dependence on the gap size d. Thus for specific metallic surfaces, this relation enables estimate the near field heat flux at cryogenic temperatures over micrometric distances.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10306 - Optics (including laser optics and quantum optics)

Project

<a href="/en/project/GA20-00918S" target="_blank" >GA20-00918S: Interplay of convective heat transfer and turbulent flows with rotation in classical and quantum phases of cryogenic helium</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Cryogenics

ISSN

0011-2275

e-ISSN

1879-2235

Volume of the periodical

113

Issue of the periodical within the volume

January

Country of publishing house

GB - UNITED KINGDOM

Number of pages

6

Pages from-to

103156

UT code for WoS article

000618659400003

EID of the result in the Scopus database

2-s2.0-85099146919