The present paper aims to investigate convective thermal transfer through polysynthetic porous media. The present analysis takes into account the fact that the most important transformations take place at the interface between these porous media and the wall of the flat micro heat pipes (FMHP). In order to develop the thermal transfer models, various surfaces of the polysynthetic material were mapped by aid of laser profilometry. This allowed for accurate measurements of the polysynthetic material dimensions, which permitted to determine several characteristic parameters for the convective thermal transfer process. Thus, in a first stage, the total thermal transfer coefficient was determined for the porous medium, as well as the Nusselt numbers corresponding to liquid diffusion in porous copper and polysynthetic media. The coefficient of the maximum pressure gradient was also computed for unitary speed amplitude for the fluid motion through the boundary layer. The present paper examines the phase shift between the pressure gradient and the liquid velocity through the boundary layer as well as the viscous Basset forces due to the crossing of the boundary layer. Particular attention is paid to calculating the friction coefficients of the liquid flowing through the porous media.
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