(60as) Instabilities of Bulk Dielectric Fluids Under Corona-Initiated Charge Injection

Electrohydrodynamic (EHD) flow induced in dielectric fluids by charge injection is capable of producing convective instabilities accompanied by surface deformation of fluids. This work presents the results of experimental observations of the EHD flow induced in bulk dielectric liquid layers using corona discharge. A method for deformation analysis of surface liquid is presented and used to characterize the convective instabilities and bulk deformations formed within the fluid. The governing liquid properties for the deformations are discussed indicating the vital role of surface tension and viscosity. Critical voltages at which rapid transformation of the liquid’s deformation occurs are identified and discussed. Consideration is also given to the potential application of the EHD flow as an air-wave type EHD pump, including analyses of pumping performance and its governing parameters. The liquid layer thickness is shown to be a dominant parameter in the efficacy of such designs. The non-uniformity of the induced electric field showed potential application in phase separation which demonstrated by water droplets coalescence.