A. A. Pozubenkov

Influence of the cathode and anode jets on the properties of a high-current electric arc

AbstractA study is made of the effects related to the formation of electrode jets in discharges in hydrogen and air at a current of 105–106 A, a current growth rate of 1010 A/s, an initial pressure of 0.1–4.0 MPa, and a discharge gap length of 5–40 mm. After secondary breakdown, jets are observed in a semitransparent discharge channel expanding with a velocity of (4–7)×102 m/s. The formation of shock waves in the interaction of the jets with the ambient gas and the opposite electrode is observed by the shadowgraphy method. Seventy microseconds after the beginning of the discharge, the pressure of the metal vapor plasma near the end of the tungsten cathode amounts to 177 MPa. The brightness temperature in this case is T=59×103 K, the average ion charge number is

Investigation of anode and cathode jets influence on electric arc properties with current up to 500 kA

\overline m = 3.1

High-current discharge channel contraction in high density gas

, and the metal vapor density is n=5.3×1019 cm−3. After 90 µs, the average ion charge number and the metal vapor density near the anode end are

High-current channel characteristics in high-pressure gas

\overline m = 2.6

Erratum: “High-current discharge channel contraction in high density gas” [Phys. Plasmas 18, 122702 (2011)]

and n=7.4×1019 cm−3, respectively. Based on the experimental data, possible reasons for the abnormally high values of the total voltage drop near the electrodes (up to ∼1 kV) are discussed.

SOFT X-RAY RADIATION FROM THE HIGH-CURRENT PULSED DISCHARGE INITIATED BY WIRE EXPLOSION IN HIGH-DENSITY HYDROGEN

3, a current of #1.5 MA, energy stored at 1.3 MJ, and a circuit ringing frequency of 1 kHz. A diagnostic discharge chamber was constructed to simulate gas heating in the electric discharge launcher (EDL) discharge chamber and to facilitate the use of a high-speed camera. Based on the arc dynamics study in the diagnostic discharge chamber, estimates of the temperature and conductivity of the arc channel were carried out for the EDL chamber. The measured pressure of 200 MPa and conductivity of 230 (X 3 cm) 21 correspond to temperatures of (3.3‐ 3.5) 3 10 4 K and of (2.3‐ 2.4) 3 10 4 K for the arcs, burning in copper vapor and hydrogen, respectively. The real temperature seems to lie between these two values. Since pressure equilibrium in the volume was reached, acoustic oscillations may be used to evaluate the gas temperature. The moving arc causes shock waves that are measured by pressure transducers, placed along the discharge length, and by high-speed camera photographs. The arc-to-gas energy transfer efe ciency rises along with initial H 2 pressure increase and reaches 90% for 40 MPa. Both the propagation of the shock wave and the arc radiation absorption contribute to this rise.