Displacement and Diffusion in Fluid-Flow Arc Extinction

The displacement and diffusion theories of arc extinction in flowing fluids are defined and contrasted. The question as to the possibility according to hydrodynamical principles of the formation of the wedge required by the displacement theory is considered and decided in the negative. Photographic evidence is also found to contradict the displacement theory. How turbulence will multiply diffusive effects is considered, and an estimate of l00fold multiplication is given for conditions existing in gas blast breakers. This enhancement of diffusion by turbulence is found to make the diffusion theory adequate for accounting for the circuit interrupting capacities of arcs in gas blast circuit breakers.