In order to improve the arcing capability of multiple series gaps, it is very important to understand the arcing principle and the influence of the control length of airflow passage on the arcing process. From the perspective of energy balance, this paper analyzes the feasibility of arc extinguishing by self-ejecting airflow and deduces that the airflow velocity is positively correlated with the control length of the airflow channel. Increasing the control length of the airflow channel can promote airflow development, enhance convection heat dissipation power, accelerate arc cooling, and, thus, improve arc extinguishing efficiency. In this study, a two-dimensional geometric model of the arc extinguishing channel was built through the COMSOL Multiphysics simulation platform, the discharge heat transfer process of the arc under the action of airflow coupling was simulated, and the effectiveness of the arc extinguishing device was verified. The results show that the arc can be extinguished and reignited more quickly and effectively by extending the control length of the airflow passage.