Dynamic evolution of arc plasma in a semi-enclosed arc-extinguishing chamber and its influencing factors

Multi-chamber arc-extinguishing has been widely researched and used to protect transmission and distribution lines from lightning. Its principle is to divide a long-gap arc into multiple short-gap arcs using multiple semi-enclosed arc-extinguishing chambers. To study the dynamic evolution of arc plasma in an arc-extinguishing chamber, we establish a three-dimensional simulation model of arc plasma in a semi-enclosed arc-extinguishing chamber by solving the Navier–Stokes and Maxwell equations. We analyze the dynamic evolution of an arc from the inside of the chamber to the outside. An impact current test platform is built and the arc motion is photographed by a high-speed camera, revealing the acceleration of the arc in the semi-enclosed chamber. Finally, the influence of chamber dimensions on key arc parameters is analyzed. In the simulation, the time when the arc completely moves out of the chamber and is extinguished is consistent with the experimental images, which verifies the accuracy of the simulation model. The arc temperature, chamber pressure, and airflow velocity first increase in an oscillating manner and then slowly decrease with time. The change of the opening diameter will lead to the obvious change of the arc temperature maximum. The opening diameter is the main chamber dimension that affects the arc temperature. The electrode spacings have the most obvious effect on the maximum pressure in the chamber. The minimum pressure in different chamber dimensions is lower than the atmospheric pressure. The influence of opening diameter, distance from central axis to closed side, and opening wall length on the maximum airflow velocity is the same, and the maximum airflow velocity decreases with the increase in these dimensions. The influence of electrode spacing on the maximum airflow velocity is opposite to them.