COMPUTER SIMULATION OF A POROUS MEDIA COMBUSTOR FOR SOLID FUEL UTILIZATION

Abstract

The fossil fuel combustion scheme causes not only energy resources depletion, but also results in global warming and climate change issues. This study investigated a performance combustion system by applying the concept of porous media technology using waste stainless steel nuts and by using wood charcoal as solid fuel. The experimental setup was done for two main cases: with porous media (case II) and without (case I) the porous media. The setup with the porous media was further configured according to sizes: 8 mm (case II-A), 10 mm (case II-B), and 12 mm (case II-C). The collected data were used to determine the setup with the highest heat transfer efficiency to the water tubes during combustion thereby giving a higher calorific value to the system and then comparing it to a nonporous kiln. Based on the results, porous media encourages higher heat transfer efficiency as observed from the rise in the temperature of water at the heat exchange chamber during the experiment. Porous media induces both the occurrence of conduction and convection heat transfer to water tubes resulting to higher heating temperatures as compared to the one without porous media. The simulation solid fuel porous media combustor (SFPMC) system was applied by the computer with ANSYS software. The experimental study was conducted in two important cases: without porous media and with porous media using three sizes of stainless steel nuts (8, 10, and 12 mm). It was found that the results obtained by computer simulations in all cases were consistent with the heat radiation combustion theory of porous media. And it was consistent with the study results from the experiment. From a comparative study of solid fuel combustion combustor with and without porous media installed, it was found that the combustors with installed porous media demonstrated higher heat transfer efficiency than combustors without installed porous media. Furthermore, the effect of using varying sizes of porous media was explored by using 8, 10, and 12 mm. stainless steel nuts in the study. With the porous media technique, the 10 mm size stainless steel nuts with a porosity of 0.53 greatly improved the performance of the proposed solid fuel porous media combustor (SFPMC) system. At steady state combustion conditions, a maximum average combustion temperature reached 1,002 ͦC and an average thermal efficiency of 67 %, was obtained.