Chambered diffusion flames for different supply temperatures

A complete description of chambered diffusion flames is presented using activation-energy asymptotics. Response curves are obtained describing the unburnt fuel fraction R as a function of its injection rate M. Their shapes depend on the specific parameter values T₀ and T₁, the supply temperatures of fuel and oxidant, and T_c, a temperature which characterizes the pressure level in the chamber. In addition to the isola and S-shaped curves found for equal supply temperatures, U-shaped and monotonic curves are now possible, the former being new to combustion. In every case explicit formulas for M are given at turning points of the curves, which correspond to ignition and extinction.