On the Development of Injection Cathode Electrodes for EHD Transducers

Abstract

Purpose To study the possibility of changing cathode injection in a grid axisymmetric EHD transducer with planeparallel modified electrodes.Methods. An estimate of the influence of the edge effect of electrode grids on the surface conductivity in the periphery of the interelectrode gap was obtained by numerical simulation, and the optimal geometry of the electrode holders of the grid EHD transducer was determined. Using the method of numerical calculation in the software environment Agros 2D, as well as using the analysis of SEM scans and the method of estimating the form factor of structures, the parameters of local electric fields of the structures of the surfaces of wires of grid electrodes modified during laser scribing were obtained.Results. The results of the development of a grid system of electrodes for electrohydrodynamic converters with enhanced cathodic charge injection are presented. The influence of the edge effect on the operation of EHD transducers is analyzed. The possibility of improving the grid electrode system of a model EHD pump is described. The composition and shape of microand nanostructures after scribing on the FMark-20RL laser marking complex have been studied. A qualitative estimate of the local electric field strength on nanostructures obtained by laser scribing of brass grids with a characteristic radius of 50 nm is made, which indicates an increase in the cathode injection of negative charges in the EHD system. With a distance between the electrodes of 1.5 mm and a potential difference between the electrodes of 1.5 kV/cm, the magnitude of the local tension at the top of the nanostructure with a curvature radius of about 50 nm can reach 5.5⋅107 V/cm.Conclusion. Laser scribing in the form of concentric circles of brass grid electrodes makes it possible to intensify cathodic charge injection by amplifying local electric fields from microand nanostructures. The use of plexiglass dielectric holders can reduce surface leakage currents at the periphery of grid electrodes.