Numerical Study on Soot Suppression of Acetylene Diffusion Flame by Acoustic Oscillated Combustion

The suppression of soot generated from acetylene nonpremixed combustion was investigated by following the numerical simulation method. The combustion and soot formation were predicted by the eddy-dissipation and Moss–Brookes models, respectively. The rate of soot formation was decreased by applying acoustic oscillation. The influences of oscillating velocity, frequency, flow rate of acetylene, and Reynolds number on the rate of soot formation were studied. Results showed that the maximum efficiency of soot suppression exceeded 90%. An increase in Reynolds number resulted in enhanced soot suppression efficiency. It is considered that the boundary layer of the soot particles was reduced when the Reynolds number increased. This could potentially result in the enhancement of mass transfer, thus causing the reoxidation of the soot in the oxidation zone. Reoxidation of soot resulted in reduced soot generation. The flame temperature increased simultaneously.