Experimental Study on Combustion Characteristics of Methane Vertical Jet Flame

A jet flame is a common type of flame in fires in the oil and gas industries. At present, research on jet flames is still not comprehensive enough. To systematically investigate the combustion characteristics of vertical methane jet flames, experiments were conducted on vertical methane jet flames, supplementing the existing experimental data on jet fires. The study reveals variations in the flame shape, center temperature, and thermal radiation with different flow rates and nozzle diameters, and the mechanisms of change in the flame center temperature and thermal radiation are discussed. The results show that increasing the gas flow rates and nozzle diameters led to a greater flame height and width. Along the flame axis, the temperature initially rose and then decreased with an increasing vertical distance from the nozzle. For smaller nozzle diameters, the flame temperature increased with the flow rate beyond the peak temperature point. Additionally, higher flow rates and larger nozzle diameters raised the height at which the maximum thermal radiation occurred. The thermal radiation near the flame’s top exceeded that in the middle, while minimal changes were observed near the base. The jet flame’s lift-off height and shape significantly influenced the distribution of the centerline temperature and thermal radiation. These findings provide valuable insights for the effective management and control of gas jet fires.