Infrared thermographic evaluation of flame turbulence scale

• 2–16 Hz flame temperature pulsations are conditioned by flame flow parameters.
• Experimental temperature patterns correlate well with flame turbulence scale.
• Turbulence scale in a chemical gas can be evaluated by temperature variations spectra.
• The micro-volumetric burning in turbulent vortices is a determinative mechanism of fuel burning.

This paper reports both theoretical predictions and experimental results of the use of infrared thermography for determining the scale of turbulent vortices in flames of burning liquid hydrocarbon fuels and flammable vegetation. The size of flames, as indicated by temperature instabilities observed in infrared thermograms, agrees fairly well with the size of turbulent vortices calculated by analyzing the spectra of flame temperature pulsations.