Study on Ignition Characteristics of Microwave Radiation Ignitor

This study explored methods used to improve the ignition efficiency of a microwave radiation igniter; experimental analyses were conducted to characterize the device’s performance in a model combustion chamber. High-speed imaging combined with an image intensifier tracked flame kernel formation and propagation dynamics under varying airflow rates, residual gas coefficients, and microwave pulse parameters. The results demonstrate that increased airflow rates reduced the relative decline in ignition delay time under microwave application, with the flame area growth curve exhibiting a steeper slope compared to non-microwave conditions. Elevated residual gas coefficients enhanced the microwave-induced reduction in ignition delay time, though this effect weakened significantly in fuel-rich environments. Additionally, higher microwave pulse frequencies and peak power levels both contributed to shorter ignition delay times; the delay decreased linearly with the rising pulse frequency and followed a power-dependent reduction trend. These findings systematically quantify the synergistic effects of flow dynamics, residual gases, and microwave parameters on ignition performance.