Arc motion and wave propagation in arc chambers with lateral chinks

The effect of lateral chinks on shock wave propagation and arc motion in simplified arc chambers with parallel arc runners were investigated both experimentally and theoretically. Pressure transients were recorded at different positions of the arc chamber. The current supply was symmetric with respect to the arc in order to minimize the effect of the self-blast field on the arc; an external transverse blast field was applied. The arc motion was observed opto-electronically. To describe the arc region, the previously developed slug model was applied. The wave propagation along the arc chamber was treated as spatially one-dimensional. Mass and energy losses due to the chinks were taken into account. Both for shock wave propagation and arc motion good agreement between theoretical predictions and experimental data was obtained with low computational effort. It turned out that narrow chinks favor fast arc motion on parallel arc runners.