Simulation of the Diffusion Process of SO2 Molecules from SF6 Insulated Electrical Equipment to SO2 Detection Device

Abstract

Online monitoring of SF6 decomposition product SO2 gas is an effective method to monitor the internal insulation status of SF6 insulated electrical equipment. However, the measured equipment and monitoring devices can only be connected through a thin tube, the decomposition gas SO2 generated inside GIS takes a long time to reach the monitoring device, which affects the timeliness of detection. In this paper, a gas transfer acceleration measure based on external flow disturbance is proposed, and multi-physical field simulation software is used to simulate and analyze the proposed acceleration measure. In the simulation, gas diffusion and forced convection are considered. The simulation results show that the diffusion process is affected by the diameter and length of the connecting tube under the natural diffusion condition. As the diameter of the connecting tube increases and the length shortens, the diffusion speed increases; The external flow disturbance can effectively accelerate the gas transfer process, and the main influencing factors include flow velocity and disturbance times.