Experimental investigation of porous media combustion in a planar micro-combustor

The micro-combustor (emitter) is a key component of the micro-thermophotovoltaic (TPV) system. In order to improve the system efficiency, higher wall temperature and uniform distribution along the combustor wall is desirable. Porous media combustion of premixed H2–air in a planar micro-combustor with the channel width of 1 mm is experimentally studied. The wall temperature is measured by using an infrared thermometer under the flow conditions of Ф = 0.6–1.0 and U0 = 2–3 m/s. The effects of flow conditions and position of the porous media on both the wall temperature distribution and the emitter efficiency are investigated. The experimental results indicate that the wall temperature increases with increasing mixture velocity, and higher emitter efficiency is achieved for mixtures with Ф ≈ 0.8. In addition, the flames are found to be effectively anchored by the inserted porous media, despite the change of flow conditions. The emitter efficiency was noted to be significantly influenced by the position of the porous media, for which the mixture preheating (by the combustor wall) is believed to be a main reason.