Image analysis of gas-phase EHD flow field for needle-plane electrode system

Velocity distribution of a gas-phase electrohydrodynamical (EHD) flow on a needle-plane electrode system was experimentally analyzed by a particle image velocimetry (PIV). The flow visualization for suitable image analysis was carried out by diffusing insulating oil vapor and using an image intensifier. The Coulomb´s force as a typical driving force of ionic wind inception was numerically estimated by current continuity equation and Poisson´s equation with a boundary condition of corona discharge current distribution. For analyzing the observed ionic wind, the intensity of ionic wind velocity near the corona discharge electrode was characterized with the estimated Coulomb´s force density.