Heat transfer characteristics of a pair of impinging rectangular flame jets

Experiments were carried out to study the heat transfer characteristics of a pair of premixed, laminar, rectangular, butane/air flame jets impinging vertically upon a water-cooled flat plate. The effects of jet-to-jet spacing and the nozzle-to-plate distance on heat transfer were examined. The Reynolds number of the exit flow was 800. The non-dimensional jet-to-jet spacing ranged from 0.9 to 4.1, while the non-dimensional nozzle-to-plate distance varied from 1 to 6. The between-jet interference decreased with increasing jet-to-jet spacing and nozzle-to-plate distance. Both the maximum local and average heat flux occurred at a moderate jet-to-jet spacing of twice effective nozzle diameter, and when the nozzle-to-plate distance was equal to the effective diameter of the nozzle. The heat flux decreased faster along the shorter sides of the slot jets than the longer sides.