Induction charging nozzle for flat fan sprays

An induction charging nozzle has been developed for use with a fully hydraulic, flat fan, water spray. Charging is achieved by passing the spray between two relatively small diameter electrodes whose position can be changed to impart the maximum deposition current on a collection screen. A simple, analytic model was first derived to gain fundamental knowledge about the relationships between the variables that determine the deposition current (x and y electrode position, power supply voltage, and nozzle pressure), and to aid in the prediction of the optimum electrode location. The nozzle was then tested to verify the trends indicated by the model and test the hypotheses concerning the choice of electrode design. The model and experimental data trends matched well. The hypothesis for using small electrodes to help avoid issues associated with electrode wetting was verified. As also indicated by the model, experiments showed that decreasing the x-spacing between the electrodes and the spray resulted in an increase in deposition current; however, in the experimental case, droplet impact issues were revealed as the x-spacing became very small. The best y-location, relative to the nozzle orifice, for the electrodes was also clearly revealed.