Effect of addition of СО$_2$ to the fuel on combustion of gas jets in air

Results of an experimental study of the effect of addition of СО$_2$ to methane and to a propane-butane mixture on conditions of stabilization of the diffusion flame in air are reported. It is shown that the flame lift-off length substantially increases with increasing fraction of СО$_2$ in the fuel; the main reason is the changes in the velocity and concentration in the region of the “ignition” points; a secondary factor is an increase in the characteristic combustion time. Data on the influence of the СО$_2$ admixture in the fuel in amounts greater than the fuel flow rate up to $\approx$1.5 times on the characteristic combustion time are obtained.