Probe measurements in a discharge with liquid nonmetallic electrodes in air at atmospheric pressure

Discharges with liquid nonmetallic electrodes of much interest for applications are investigated. It is found that a dc discharge between two streams of tap water in air at atmospheric pressure is stable at a current of 40 less than or equal to I less than or equal to 100 mA. The discharge exists in the diffuse (volume) form with a relatively low current density (similar to0.2 A/cm(2)) and a high (above one kilovolt) voltage drop across the air gap (similar to1 cm) between the water electrodes. The current density and voltage depend only slightly on the discharge current. Probe measurements show that three regions can be distinguished in the discharge: two electrode regions (1-2 mm in length) and a discharge column with a constant electric field of approximate to0.8 kV/cm (i.e., E/N approximate to 20 Td, because the gas in the discharge is heated up to 1500-2000 K). The average electric field strength near the electrodes is E approximate to 2-3 x 10(3) V/cm (E/N approximate to 60-80 Td). The charged particle density in the column is n similar to 10(12) cm(-3). The probe measurements of n agree with the previous microwave absorption measurements. The water vapor concentration in the column is also estimated from probe measurements. (C) 2002 MAIK "Nauka / Interperiodica".