Experimental analysis of a new attraction force applied on metal particles

A traveling wave conveyor (TWC) is generally employed for moving high-resistivity micronized particles. In this study, a planar TWC was used to analyze the attraction force applied on metal pieces. A three-phase conveyor comprising parallel electrodes that obtained power from high-voltage amplifiers (2 kV, 20 mA) controlled by digital function generators was used for analyzing the attraction force on 15 x 15 mm(2) square metal pieces made of copper, bronze, and steel. The TWC was fixed on a mechanical device that allowed its manual inclination from 0 degrees (horizontal; initial condition) to 180 degrees. The intensity of the force was then estimated by measuring the drop angle at which the metal piece detached from the surface of the conveyor. The obtained results revealed the existence of an attraction force that depends on the frequency, amplitude, and waveform of the applied voltage. This force is maximum at high voltages and frequencies and for a square waveform.