Numerical Study of Jet Inverse Diffusion Flames Issuing from an Elliptical Burner

Abstract

The present study numerically examines the influence of the central air velocity on the combustion characteristics of Inverse Diffusion Flames (IDFs) of an elliptical burner under a constant thermal input. The burner configuration consists of a central circular air pipe surrounded by an annular elliptical fuel tube. The computational model is benchmarked with a previous experimental work that utilized Liquefied Petroleum Gas (LPG) as the fuel. The simulations were conducted using various turbulence models, as well as detailed and simplified LPG compositions. The flame structure is affected by the elliptical shape of the fuel jet, which generates different radial profiles on both major and minor axes. The results indicate that the simplified LPG can achieve comparable results with lower computational expense. Moreover, augmenting the air velocity lowers the flame temperature and consequently reduces NOX concentrations. CO concentration also diminishes with increasing the air velocity due to the improved mixing and entrainment.