Experimental Investigation of Fluid Flow and Internal Convection Heat Transfer in Mini/Micro Porous Media

The flow characteristics of different gases such as air, helium and carbon dioxide and internal convection heat transfer between the solid particles and the fluid in mini/micro porous media were studied experimentally. The test sections for fluid flow and heat transfer were made of sintered bronze particles with average diameters of 225 mu m, 125 mu m, 90 mu m and 40 mu m. The experimentally measured friction factors with consideration of compressibility for air, helium and carbon dioxide in the porous media with average diameters of 225 mu m and 125 mu m agree well with the known correlation for normal size porous media (the correlation of Aerov and Tojec), especially at the relatively high Reynolds numbers. The experimentally measured friction factors for air, helium and carbon dioxide in the porous media with average diameters of 90 mu m are slightly less than the correlation of Aerov and Tojec at the relatively low Reynolds numbers. The experimental values for the friction factors for air, helium and carbon dioxide in the microporousmedia with 40 mu m average diameters are much less than the correlation of Aerov and Tojec. The results show that rarefaction effects occur in air, helium and hydrogen flows in the microporous media with particle diameters less than 90 mu m. The internal convection heat transfer coefficients between particles and fluid for air, helium and carbon dioxide in the micro porous media were determined experimentally.