Аннотация:The model of a working medium of complex microstructure is used tocalculate processes in a channel of one stage of an Electrohydrodynamic (EHD)device. The flow of a multicomponent fluid consisting of neutral particles and asmall admixture of two kinds of oppositely charged ions through a plane channelwith dielectric walls is investigated. Two plane electrodes penetrable by the fluid andexerting no hydrodynamic drag force are placed in the cross-sections of the channel.These electrodes and the space between them form a stage of an EHD device appliedto increase the pressure in the medium. It is shown that the pressure drop and thetotal volume charge of the stage almost linearly depend on the applied voltage ina certain range; however, there is a critical value beyond which a further increasein voltage reduces the efficiency of the converter. This is due to the influence ofinjection of negative ions from the cathode, which grows with increasing field andcauses redistribution of the volume charge in the interelectrode space.