Combustion Roar of Turbulent Diffusion Flames

Pertinent literature is reviewed and experimental data on the combustion roar of turbulent, natural-gas, diffusion flames are presented. These data were obtained on two experimental burner rigs, one that consisted of two impinging fuel jets, and one that consisted of eight almost impinging fuel jets. Variables considered include the effect of firing rate up to several hundred thousand btu/hr, spud size, spud spacing and orientation, on both overall noise level and noise spectrum. The data are compared to similar observations from industrial combustors. Some speculations as to the specific source of the combustion roar are made.