Dynamics of Swirling Flow in a Dump Combustor at Elevated Pressures

This paper reports an experimental investigation of the flow field inside a low aspect ratio dump combustor with inlet swirl and choked exit. The length of the combustor studied was less than the reattachment length for the separated flow. The tapered exit of the combustor was choked by a needle valve to investigate the effect of elevated chamber pressure on the flow field of the combustor. The variation in wall pressure and velocity at different locations and Reynolds number was studied. It was observed that the turbulent intensity increased with the swirling flow and decreased with an increase in the chamber pressure. The exit choking reinforced the recirculation. The velocity distributions were corroborated by comparing the frequency spectrum with the wall pressure distributions and the results were found to be in good qualitative agreement with each other. This study will be helpful to design the combustor for different operating conditions.