Thermal performance investigation of a premixed surface flame burner used in the domestic heating boilers

This study investigated a premixed surface flame burner using chemiluminescence and image analysis. The burner was experimentally analyzed in equivalence ratios of 0.4 1.3 and operating heating capacities of 11.74 17.14 kW. The OH* emission showed a peak in the range of 0.77 0.83. The flame temperature variations were measured to adapt the results of OH* emission to the flame heat release, showing a peak in the lean range of 0.76 0.85. The air/fuel mixture was affected by flame height and preheated by the surface. Consequently, maximum heat release occurred in the lean range. Flame stability was studied using image analysis. The stable flame was in the same equivalence ratio range of the maximum OH* in operating burner powers. A gas analyzer determined the pollutant concentrations. The NOx and CO were detected below 20 ppm in the equivalence ratio of 0.77 0.83. Finally, a performance map was provided for the burner that showed thermal stable areas of flame regimes. The proposed operation can be derived by a performance diagram for the input burner power. The satisfactory operating zone of heat release (82% higher OH* intensity compared to stochiometric condition), pollutants, and the stable flame includes an equivalence ratio range of 0.77e0.83. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study investigated a premixed surface flame burner using chemiluminescence and image analysis. The flame temperature variations were found to be influenced by OH* emission and peaked in the lean range. Image analysis helped determine the stable flame range, while pollutant concentrations remained low under specific equivalence ratios.