关键词: 多孔介质, 辐射器, 燃烧器

Abstract: A SiC porous medium radiator (PMR) with heat recuperator was built and its performance was experimentally studied. The effect of equivalence ratio and combustion power on ignition, combustion characteristics and radiant efficiency were evaluated. The results indicate that increasing the combustion power can lead to higher surface temperature and lower temperature gradient at a fixed equivalence ratio, and that there is an optimal equivalence ratio at which the lowest gradient is gained at a fixed power. Assisted with heat recuperator, uniformity of surface temperature along the axial direction and radiant efficiency increase. Equivalence ratio and combustion power have significant effect on radiant efficiency. At low power, increasing power results in obvious augment in radiant efficiency. There is an optimal equivalence ratio leading to a perfect radiant efficiency for a given operating power. The setup in this paper can gain a radiant efficiency as high as 347% at power 70 kW and equivalence ratio 075 without thermal recuperation. With heat recuperation, however, the optimal equivalence ratio drops to 054 and the corresponding radiant efficiency reaches 369%.

Key words: porous medium, radiator, combustor