Flammability limit and flame visualization of gaseous fuel combustion inside meso-scale combustor with different thermal conductivity

This study experimentally investigated effect of thermal conductivity on the combustion characteristics of gaseous fuel inside a meso-scale combustor. Combustion characteristics that were observed in this research include flame visualization and flammability limit. Quartz glass, stainless steel and copper tubes with inner diameters of 3.5 mm were used as combustors. Stainless steel wire mesh was inserted inside meso-scale combustor as a flame holder. Liquid petroleum gas (LPG), which is common fuel used by Indonesian people, was used as a gaseous fuel. A stable blue flame was established inside meso-scale combustor at the downstream of wire mesh for all combustor with different thermal conductivity. Furthermore, flame color is blue for combustion of fuel lean or stoichiometric mixture, and blue-green for combustion of fuel rich mixture. Meso-scale combustor with the highest thermal conductivity has the narrowest flame cross section area, especially at lower reactant velocity. Vice versa, this combustor has the widest flammability limit, mainly at the higher reactant velocity.