INFLUENCE OF FUEL-SIDE HEAT-LOSS ON DIFFUSION FLAME EXTINCTION

The influence of a fuel-side heat loss zone on a diffusion flame estab lished between fuel and oxidizer reservoirs is investigated using a mo del heat loss profile. The radiative heat loss suffered by a flame due to particulate soot served as the background motivation for this stud y. For each chosen flame, the intensity, width and location of the hea t loss profile were parametrically varied to assess the sensitivity of the flame to heat losses. The influence of such variations on the hea t release, the heat flux to the reservoir walls, the radiative fractio n and the drop in flame temperature was studied. Emphasis was placed o n the phenomenon of flame extinction due to increased heat losses. Ext inction plots were generated for a range of fuel and oxidizer reservoi r mass fraction values. The influence of the losses is characterized b est by the integrated value of the heat loss profile. In all situation s studied, the temperature and reactivity peaks moved toward the fuel side with increased heal losses. (C) 1998 Elsevier Science Ltd. All ri ghts reserved.