Improvement of combustion characteristics for hydrogen-air mixture using modular structure in a novel micro combustor

In the present work, the effect of using modular structure on combustion characteristics of the premixed lean hydrogen-air mixture is investigated by utilizing the three-dimensional CFD model, detailed chemistry and transport taking into account heat transfer through the wall combustor. Combustion characteristics are studied for different parameters, namely inlet velocity, wall thermal conductivity and tube curvature for modular structure and it compares with results of simple structure. The results show that using modular structure can significantly move flame front toward inlet section. In modular structure, the role of heat transfer due to secondary fluid increases in comparison with heat transfer in combustor walls. It improves thermal stability in the micro combustor and therefore, the role of wall thermal conductivity and heat transfer in wall combustor will be decreased for modular structure. Using modular structure for lower tube curvature is more effective which it has been shown for tube curvature of one and two.