In order to solve the lightning protection problem of transmission lines

on the basis of parallel gap

we presented an arc-extinguishing lightning protection device based on the explosive airflow. By establishing a chain arc model

we analyzed the forces exerted on arc element

and using the detonation similarity theory to calculate the pressure of explosive wave

we deduced the velocity components’ control equations of arc element.Moreover

using the ANSYS AUTODYN software to simulate the coupling process of explosive airflow and arc plasma

we numerically simulated airflow fields and temperature fields

and made arc-extinguishing test. The results show that the velocity components of arc element have nothing to do with the length of arc element

but associated with explosive airflow pressure. And the greater the airflow pressure is

the faster the arc speed is

the more co

nducive to extinguishing arc. Explosive airflow velocity can reach a maximum of 6 000 m/s

the temperature drops from the highest 14 × 10

3

K to 3× 10

3

K when the time is 4.6 ms

and arc is extinguished under the action of explosive airflow without rekindle.