Experimental and numerical studies on vortical structure and temperature field in a bluff-body burner

Abstract

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.Vortical and thermal structures of non-premixed propane flame in a bluff-body burner are studied experimentally and numerically in the transition from laminar to turbulent flow. In particular, we focus attention on the effect of annular air flow on the flame. The annular air flow promotes development of a shear layer vortex street in the central fuel jet and lends to change in the direction of rotation of the vortex. These features are supported by the numerical simulation. The agreement of experimental and numerical vortex frequencies is satisfactory. The fluctuation in temperature corresponds well to the vortex dynamics, and there is a peak in rms temperature inside and outside the flame, respectively.