An experimental study of the optical characterization of AC electrohydrodynamic fields by particle image velocimetry

This paper describes the optical characterization of electrohydroctynamic (EHD) fields in liquid dielectrics subjected to AC high voltage. The velocity fields are obtained by a particle image velocimetry (PIV). The EHD fields are formed in 10 cSt silicon oil and ethanol with different dielectric constants. The PIV requires illuminated tracer particles for the fluid flow visualization. For the requirement, particles of aluminum powder with good conductivity and polyethylene powder with high resistivity are suspended in the liquids and are not related to electrification because of the AC electric fields. From the viewpoint of EHD flow visualization, the main purpose of this study is velocity measurements of the tracer particles moved by electrostriction in the fields. The PIV applied to the measurements gives us an interesting experimental result of velocity fields for the EHD phenomena.