Turbine blade cooling using Coulomb repulsion

Abstract

In order to preserve the integrity of the film cooling layer on a turbine blade, it is proposed that the blade is raised to a positive voltage with respect to a nearby negative electrode. The positive ions within the hot combustion products are repulsed from the blade, transferring that force to the surrounding neutrals. The neutral gas within the film cooling layer experiences no such body force. Therefore the boundary between the two fluids acts as a stably-stratified interface, analogous to the surface of the ocean. The flatness of the interface is determined by a Richardson number, the ratio of the potential energy of the Coulomb force to the kinetic energy of the turbulence. If Ri is greater than unity, the interface is relatively flat and the film cooling layer remains preserved.