Effect of electrode shape, material and chemical structure on electric strength of some liquid hydrocarbons

The power frequency insulation breakdown phenomena in pure hydrocarbon liquids including straight, branched, and ring-type chemical structures is investigated. The electric strength of n-pentane, n-hexane, n-heptane, benzene, toluene, xylene, and 2,2,4-trimethyl pentane was determined using 13-mm-diameter spheres of brass, copper, and aluminium. In order to study the effect of electrode material and shape on breakdown strength, different shapes of electrodes of commonly used metals were investigated, n-hexane with a sphere-plane arrangement yields maximum electric strength and n-pentane with a point-point arrangement yields minimum electric strength. The electric strength is very much dependent on electrode material and shape. The electric strength varies substantially as the chemical structure of these liquids branches out