An Investigation of Hydraulic and Thermal Performance of Metal Foam Filter

Abstract

Hydraulic and thermal performance of metal foam filter were investigated numerically and experimentally in the present work for clean and dusty air in a, copper foam filter. Two pore densities of copper foams are used, 10 PPI with average pore diameter 905.7 μm with porosity (90%) and 40PPI with average pore diameter 568.6 μm with porosity (89%). Copper foam filter exposed to different air inlet constant temperature of clean and dusty air for different values of pore Reynolds number (Rep) which are (119.1, 168, 218, 306.8, and 356.7) for 10 Pore Per Inch (PPI) and are (73.8, 104.21, 135.21, 190.3, and 221.3) for (40PPI). The samples are tested in a wind tunnel and exposed to a clean and dusty air at different inlet constant temperatures (29.7˚C, 40˚C, 50˚C, 60˚C, 65˚C) as a thermal boundary condition. The tests included the measurements of pressure and temperature distributions through the metal foam samples. In the numerical solution, the effect of temperature and pressure are studied and discussed by using a CFD Package Comsol Multiphysics 4.3b by solving three dimensional [continuity, momentum (Forchheimer᾿s equation) and energy] equations. The numerical investigation covered all the cases of the experimental work. The results show that the absolute pressure decreased along the flow direction, and increased with the increase of pore Reynolds number. No effect of temperature was noticed on the results. For clean air the results show that the pressure drop (ΔP) of 40PPI is higher by (57.8%) than that for the 10PPI. For dusty air, the results show that the absolute pressure increased with increasing dust concentration (C) or dust density (N= 2, 4, 6 & 8), and the pressure drop through copper foam filter with 40PPI is higher by (58.09%) than that for the 10PPI, and the pressure drop for dusty air at dust density (N= 2 & 4) is higher by (33%) than the clean air at same conditions. Comparison between the present experimental and numerical results shows a similar behavior with a minimum and maximum deviation of 1-5%. The present experimental and numerical results also have been compared with available previous studies for pressure (P) with x-axis and pressure gradiant (ΔP/L) with velocity, and showed a good agreement.