The influence of burner geometry on premixed turbulent flame propagation

Abstract

The influence of burner geometry on premixed turbulent flame propagation has been studied experimentally by investigating the turbulent transport, turbulence production and burning rate in three flame configurations: they are rod-stabilized v-flames, tube stabilized conical flames and flames stabilized in a stagnation flow. In order to make comparisons of the three flames with different flame shapes and flow patterns, it was necessary to measure the velocity and scalar properties along flowlines through the flame zone. Under similar flow and mixture conditions, the magnitudes of turbulence transport within the three flames are significantly different. In contrast, the levels of turbulence production are more consistent and the turbulence kinetic energies evolve to the same level downstream of the flame zone. The burning rates of the v-flames and the conical flames are found to be consistent with turbulent-to-laminar-burning speed ratio of the stagnation flow stabilized flames. These results show that turbulence transport processes are sensitive to the flame geometry but the burning rates and turbulence production are not. The merits of these laboratory flames for the development of current theoretical turbulent combustion models are also discussed.