The criterion of DC flashover on a circular sector models

The results which we obtained on multi channels models enabled us to say that the distribution of the current is very important for flashover. By taking these observations into account we proposed a new laboratory model which has a continuous current distribution. This model is a vat having a circular sector form of variable angles and rays. The experiment result for a given resistivity of electrolyte show that the applied critical voltage and the critical current per unit of angle (1°) are constant for all sectors of various angles. Moreover the increase in the ray of the sector involves the reduction in the average of the critical voltage gradient and the increase in its values in front of the discharge. The analyses of these results allow us to confirm our flashover criterion which is as follows: If the field in the air reaches its critical distribution, the discharge evolves until flashover.