Numerical and Experimental Investigations on Performance Optimization of a Microturbojet Engine Combustor

Sudden extinction of a microturbojet engine combustor was encountered during the engine accelerating process, which motivates the present work to optimize the combustor performance. Numerical results show that by decreasing the primary zone air-introducing area and increasing the dilution zone air-introducing area, the primary zone air percentage is reduced from 39.35% to 32%, and the primary zone excess air ratio is reduced from 1.122 to 0.915, which is believed to be beneficial for flame stability both in terms of residence time and rich burn. Meanwhile, the vortex flow pattern in the primary zone varies little as the variations of the airflow distribution. The new engine, which is equipped with the optimized combustor, is tested by experiments. The successful accelerating to the rotating design speed demonstrates the effectiveness of combustor optimization work.