Heat transfer characteristics of an inverse diffusion flame with induced swirl

The flame shapes and heat transfer characteristics of methane swirling inverse diffusion flame jet are studied experimentally in an inverse diffusion flame burner. The twisted tape of 15 mm pitch (corresponding to the twist ratio of 2.5 and swirl number of 0.62) is used to create the swirl in the flame jet. The influence of twisted tape at an air jet Reynolds number varying from 1500 to 3000, equivalence ratio varying from 0.4 to 1.4 and burner surface to impingement plate distance of 10–100 mm, is studied. The heat transfer characteristics from an IDF burner are studied through an evaluation of the average heat flux distribution and its coefficient of variance for the four distinct areas on an impingement plate. Results show that the swirl augments the heat flux distribution by up to 480% for slightly richer than stoichiometric flames. Furthermore, the impact of swirling is observed to boost the uniformity of heat flux distribution.