Analysis of the air layer thickness influence on heat transfer coefficient of two-layer foil cover

Abstract

The investigation results of the heat transfer coefficients dependence on Nu and Ra numbers and natural convection onset in air layer within two plastic foils have been presented in this paper. The dependence has been investigated for different values of foil temperature differences, thickness of air layer and the angle of inclination of the two-layer foil cover towards the horizontal plane.

U radu su izloženi rezultati ispitivanja zavisnosti koeficijenata prolaza toplote prekrivke plastenika od Nuseltovog i Rejlijevog broja, odnosno od nastupa prirodne konvekcije u vazdušnom sloju koji se nalazi između dve folije. Zavisnost je ispitivana za različite vrednosti njihovih temperatura, debljine sloja vazduha i ugla nagiba dvoslojne prekrivke u odnosu na horizontalnu ravan.