Experimental Study of Ignition Characteristics in Oblique-Injected Annular Combustors Using a Pre-Chamber Ignition System

In this work, a pre-chamber ignition system is used to initiate the ignition in a premixed oblique-injected annular combustor. Although the introduction of the oblique-injecting burner in the gas turbine improved the gyratory flow motion and flow interactions during ignition within the annular combustor chamber, the flame propagation on both sides of the combustor remains asymmetrical. Hence, a pre-chamber ignitor is integrated into the oblique-injecting annular combustor to enhance the light-round process and ignition characteristics. The experimental results obtained by the visualization process through the high-speed camera are compared to the straight-injecting annular combustor under the same operating conditions. The test is carried out using different equivalence ratios and thermal power. Compared to the spark electrode ignitor, the jets issued from the pre-chamber enhanced the burning rate on both sides of the combustor, making the flame propagation process more symmetrical. The pre-chamber exhibits significant effectiveness in rapidly forming flames in lean mixtures in two different combustor types, making it the optimal solution for various operating conditions.