Influence of Heat Transfer on Jet Flame Stabilization

Experimental measurements were conducted in the stabilization zone of a non-premixed attached methane/air jet-flame. The burner consists of a straight tube whose composition material is changed to vary its thermal conductivity and thus investigate material effects on flame stabilization mechanisms. Experiments were performed over a very wide range of fuel injection velocity over the attached flame regime, covering velocity ratios between fuel and coflow both lower and greater than unity. Temperature of the burner lip as well as temperature gradients at the burner top were systematically measured, along with the radial and axial positions of flame stabilization determined from CH*-chemiluminescence imaging. Several phases were identified in terms of fuel injection velocity with associated variations of lip temperature and flame location, and important phenomena occurring in each of these phases are described and discussed in this paper.