Effect of surface emissivity on reduction in thermal conductivity in a view of simple analytical model and radiative transfer equation

• Autorzy: Koniorczyk P. , Zmywaczyk J. , Kowalski M.
• Języki publikacji: EN

Abstrakty

EN

The problem of modelling a 'thickness effect curve' in semitransparent media, using a simple analytical model based on division of the thermal conductivity thickness dependence k(z) (for a sample thickness l) into three regions of different widths, is presented in this paper. The limiting value of the sample thickness liim is comparable (in our opinion) with the mean free path of a photon and corresponds to its initial, region of thermal conductivity expressed as an exponential function of the absorption coefficient k and sample thickness l. To validate the proposed method, the results of analytical solution have been compared with the exact solution of the 1-D model of coupled radiation and conduction heat transfer in an emitting and absorbing medium.

Słowa kluczowe

EN

radiative-conductive heat transfer; reduction of thermal conductivity; thermal conductivity; emitting medium; absorbing medium

PL

przepływ ciepła radiacyjno-przewodnościowego; zmniejszenie przewodnictwa cieplnego; przewodność cieplna; ośrodek emitujący; ośrodek absorbujący

• Wydawca: Instytut Podstawowych Problemów Techniki PAN
• Czasopismo: Journal of Technical Physics
• Rocznik: 2004
• Tom: Vol. 45, no 3
• Strony: 183--193
• Opis fizyczny: Bibliogr. 14 poz., rys., wykr.

Twórcy

autor

Koniorczyk P.

• Military University of Technology, S. Kaliskiego 2, 00-908 Warszawa 49, Poland

autor

Zmywaczyk J.

• Military University of Technology, S. Kaliskiego 2, 00-908 Warszawa 49, Poland

autor

Kowalski M.

• Military University of Technology, S. Kaliskiego 2, 00-908 Warszawa 49, Poland

Bibliografia

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