Abstract:
Analytical dependence for the diffusion flame lift-off length with fuel jet discharge into the atmosphere is obtained in criterial form. The dependence can be used to determine the limiting parameters at which blow-off occurs and describe the lift-off length variation under pre-blow-off conditions, and it correlates well with earlier generalizations of experimental data. The experiments on the combustion of propane-butane and natural gas confirm the correctness of the proposed form of the analytical generalization, show the marked influence of the external shape of the gas nozzle on the lift-off parameters, and indicate that the blow-off of the turbulent diffusion flame is slower than the characteristic combustion time.
Keywords:fuel jet, characteristic combustion time, lift-off length, stalling.