Study on the discharge under water and micro bubble generation

Summary form only given. Mechanism and electrical characteristics of the discharge under 0.9% saline water have been studied. The discharge under water needs Ohmic heating to generate a void around the cylindrical electrode. The void around the electrode provides the discharge space at high voltage. Hence the electrical power dissipated in to two channels, heating the water to generate the void and generating the plasma in the void. The discharge power has been measured by a I-V Lissajous curves. After discharge in the void around the electrode, the void split into micro size bubbles and scattered in the water. The size of micro bubbles has a Gaussian distribution. However the average micro bubble size depends on the diameter of the electrode.