A contribution to the evaluation of electrohydrodynamic pumps for insulating oils

Electrohydrodynamic pumps offer the possibility of having a pumping device without moving parts. For ion drag pumps, previous approaches to the definition of the relevant static pressure have been demonstrated to be in error. The present authors investigate these errors for different insulating oils, on the basis of “ad hoc” experiments performed on a one stage ion drag pump. The hypothesis that, in the absence of flow, the working fluid can be considered at zero velocity on all the working space (i.e. viscosity effects can be ignored), is shown not to hold in all cases. Further, the experimental results suggest that the assumption of a mono-ionic process is not always valid