The results of experimental investigation of heat transfer at propane evaporation in the porous coating of the horizontal tube and at its two-phase flow streamline at the conditions of the annular mini-channel with width till 2 mm. The data were obtained on a flooded or partially flooded sample in a liquid pool or in confined space. A micro scale effect took place inside the porous body and a mini-scale effect was ensured due to annular mini-channel. Experimental results show, that such combination is favorable for the heat transfer enhancement. The availability of annular mini-channel significantly promotes to intense heat transfer (up to 2.5 - 3 times as high) at heat fluxes up to 50 kW/m2, as compared with process in a liquid pool.