The construction and operation of atmospheric nonthermal plasma jet, ANPJ, are presented in this work as well as the experimental investigations of its electrical parameters, the configuration of plasma jet column and its temperature. The device is energized by a low-cost Neon power supply of (10 kV, 30 mA, and 20 kHz) and the discharge takes place by using N2 gas with different flow rates from 3 to 25 L/min and input voltage of 6 kV. Diagnostic techniques such as voltage divider, Lissajous figure, image processing and thermometer are used. The electrical characteristics of discharge at different flow rates of N2 gas such as discharge voltage, current, mean power, power efficiency, and mean energy have been studied. The experimental results show that the maximum plasma jet length of 14 mm is detected at flow rate of 12 L/min. The results of plasma jet (heavy particles) temperature along the jet length show that jet plasma has approximately a room temperature at the jet column end. The results of zero flow rate effect on the ANPJ operation show damage in the Teflon insulator and a corrosion in the Aluminum electrodes.

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In this paper experiments and theoretical treatments [1] on 1.5 KJ coaxial plasma discharge device have been carried out to show, plasma current sheath, PCS, motion in coaxial plasma discharge by studying: the effect of nitrogen gas pressure in the range from 1 to 2.2 Torr and the axial position of PCS along the coaxial electrodes on the modification factor, actual drive parameter, PCS curvature and shape (thickness). Also the dynamics of PCS along the coaxial electrodes due to the combination effect of induced azimuthal and axial magnetic fields induction has been detected experimentally by using a magnetic probe technique.

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The present study reports the measurements of plasma current sheath (PCS) dynamics, the energy dissipation processes, and the plasma focus (PF) electrical characteristics, particularly during the axial phase discharge in a Mather-type PF device (EAEA-PF1) energized with a 30 µF capacitor bank charged with 8, 10 and 12 kV. All these investigations carried out under discharge conditions where the optimal PF action is achieved. At each charging voltage (V ch), 8 kV, 10 kV and 12 kV, the optimal PF action is studied at different argon gas pressures (P) ranging from 0.4 to 1.2 Torr. The results show that the best PF is formed at V ch = 8 kV and P = 0.6 Torr, V ch = 10 kV and P = 0.8 Torr, and V ch = 12 kV and P = 0.8 Torr. The implosion velocity (V z) results of PCS show that the maximum value of V z (4.48 cm/µs) occurs at the end of the axial phase (i.e., at the coaxial electrode muzzle), which is detected at V ch = 12 kV and P = 0.8 Torr. Moreover, a less inefficient snowplow action is observed under these discharge conditions. The energy dissipation process data indicate that at V ch = 12 kV and P = 0.8 Torr, the ratio between the total energy dissipation and the input energy has a maximum value of 90%, and the minimum residual energy left on the condenser bank (175.39 J) is also achieved under these discharge conditions.

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The experimental investigations in this paper are focused on the study of luminous radiation emission from coaxial plasma discharge device and the effect of applied transverse magnetic field <i>B_tr</i> on it. The experiment was done in (1.5 KJ - 10 KV) coaxial plasma discharge device. The discharge is operated in Nitrogen gas at pressures from 1 to 2.2 torr. Helmholtz magnetic coils are placed outside the coaxial electrodes with its axis at a distance = 3 cm from the coaxial electrodes muzzle, then <i>B_tr</i> with a maximum induction ≈ 0.85 T is applied perpendicularly to the expanded plasma from the coaxial electrodes muzzle. The diagnostics used in the measurements include a Rogowsky coil and a photomultiplier tube equipped with light collimator. The experimental results showed that the maximum intensity of luminous radiation is detected at axial distance (side view) <i>z</i> = 8 cm and gas pressure, <i>P</i> = 2.2 torr. It also showed that the maximum value of axial luminous plasma zone velocity = 2.383 × 10⁶ cm/s at <i>z</i> = 11 cm and <i>P</i> = 1.4 torr. In mode of presence of external <i>B_tr</i>, the investigations have shown that, at <i>P</i> = 1.4 torr the maximum intensity of luminous radiation (detected at end-view position) is reduced by 17%, the full width at half maximum, <i>FWHM</i> of luminous radiation signal is increased by 40 times, while the luminous radiation signal is delayed by ta = 438 µs. In two modes of operation <i>t_a</i> and <i>FWHM</i> have approximately a minimum values at <i>P</i> = 1.4 torr