Mechanisms for Temperature Decay in the Freely Recovering Gas Blast Arc

Energy loss mechanisms for the extinguished gas blast arc channel in free recovery are defined and their comparative magnitudes are explored for both N2 and SF6 gases. The arc channel temperature decay rate is found to follow at least two time constants: one corresponding to the transit time of the channel gas and the other to a later period. In addition, the influence of the gas pressure and of the initial conditions of the arc channel and the surrounding hot gas mantle at current zero on the decay rate of the channel temperature are investigated.