AbstractTo improve the efficiency of supersonic combustion apart from cavity flows, micro vortex generator is an active research for high speed combustion. The effectiveness of such vortex generators greatly depends on location and strength of growing boundary layer, which makes the experimental study complicated thereby numerical simulation becomes a useful tool prior to experiments. Reacting flow simulations have been carried out for cavity based and micro vortex based combustor using a commercial software FLUENT. At the combustor inlet, pure air is considered and kerosene is injected from the wall surfaces. It was found that at the exit plane there is considerable amount of unburnt kerosene vapour in the core regions and unused oxygen in the side wall regions in the baseline combustor due to improper fuel air mixing. Modified combustor with micro vortex generators is found to improve the fuel air mixing and performance of combustor. These results helped to understand the effectiveness of vortex generators as a mixing enhancing device in high speed combustion flows.