Two-dimensional temperature measurements in a technical combustor with laser Rayleigh scattering.

Application of the two-dimensional laser Rayleigh technique to the investigation of a large-scale industrial combustor is reported for the first time to our knowledge. Two-dimensional laser Rayleigh scattering was used to perform quantitative measurements of the temperature fields in different downstream positions of a 150-kW industrial, premixed, turbulent low-emission swirl combustor. Because of the possible interferences of the Rayleigh signal with Mie scattering and laser reflections of the burner components, some minor modifications of the design of the combustor and its gas supply were necessary. This was done without changing the basic characteristics of the burner. The quantitative and instantaneous character of the collected data allows calculation of ensemble-averaged temperature distributions and analysis of the flame structure in the turbulent combustion field. The measured temperature distribution confirms that the flame is stabilized by a central recirculation zone.