The Effect of Sphere Size on Bipolar Pulsed Discharges in Glass-Sphere/Water/Air Columns

Bipolar pulsed discharges were investigated in columns containing glass spheres and water, and with air bubbling through, using a coaxial electrode configuration. The effect of sphere size on the discharge characteristics was studied, and results showed that the diameter of the glass spheres had a significant effect on the electrical discharges in the three-phase mixture. As the sphere size increased from 2 to 12 mm, no significant changes occurred in the peak voltage and rise time of the load voltage, but a clear maximum in the tail voltage, and a minimum in the injected power per pulse, occurred in the sphere diameter range from 5 to 8 mm. The greatest electric field in the interstices between the spheres, and the rate at which a dye could be removed from the water, both exhibited a maximum in the sphere diameter range from 5 to 8 mm.