The influence of burner rim aerodynamics on the behavior of polyhedral flames of butane/air mixtures is investigated for burner rims of different geometries. By systematically varying the mixture concentration and velocity, regimes corresponding to stationary, rotating, and unstable polyhedral flames with various numbers of sides are identified. The rotational velocity and the temperature in the crest and trough regions of polyhedral flames as well as the periodic temperature fluctuation of the gases through which flames rotate are measured. The effects associated with the outer diffusion flame mantle are assessed and the influence of the conductive heat loss to the burner rim is determined. Stabilization of the Bunsen flames is also studied; for the various burner rims the critical flow velocity and concentration corresponding to flame flashback and blow-off are determined. The observations can be successfully interpreted on the bases of flame stretch, preferential diffusion, heat loss, and atmospheric entrainment.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Fuel Technology
- Energy Engineering and Power Technology
- Physics and Astronomy(all)