DETERMINATION OF THERMAL CONDUCTIVITY OF WET GAS-FILLED POLYMERIC MATERIALS
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Abstract
A geometric model of the structure of the foam plastic is presented taking into account the moisture content and wetting of the pore surface. A mathematical description of the heat transfer process in a three-component model structure of wet foam is performed taking into account vapor diffusion in the pore space. A method for calculating the effective thermal conductivity of moisture-containing highly porous gas-filled polymer materials is proposed, which considers a model of a wet material with a solid skeleton, more accurately takes into account the resistance of the porous medium of vapor diffusion, defines the conditions for the transition from partial wetting of the pore surface with liquid to complete without the need for empirical coefficients. A computational experiment was conducted, the results of which show the mutual influence of moisture content, porosity and polymer concentration on the effective thermal conductivity of the material at a given temperature.
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