Numerical and experimental study of the application of roof flat-flame burners

The objective of the work was to investigate the essential features of radiation and convection heat transfer in the chamber furnace heated with roof flat-flame burners and conventional side-fired torch burner. The effect of change in the furnace chamber height on the heat transfer rate in the furnace enclosure, particularly on the heat flux onto the heated material, was determined numerically and experimentally. The results obtained by means of a computer-based mathematical model and those obtained on the laboratory chamber furnace showed a good agreement. The experimental results showed that a decrease in chamber height from 1760 mm to 1160 mm at low temperatures of the calorimeter surfaces, in all the heating modes, led to an increase in the heat transfer rate of 10-12 per cent, and at high temperatures of the calorimeter surfaces from 10 per cent (torch burner) up to 15-20 per cent (flat-flame burners). The calculations of heat fluxes onto the load surface were conducted in order to determine the real value of the coefficient of convective heat transfer from combustion gases to the load surface. (C) 2010 Elsevier Ltd. All rights reserved.