Measuring parameters of pulse volume discharges in atmospheric-pressure air by the emission-spectroscopy and laser-interferometry methods

An experimental bench for generating pulse discharges in an atmospheric-pressure air medium is described. The results of measuring the gas-kinetic temperatures and the electron density using spectral methods and a multiple-beam Fabry–Perot interferometer, respectively, are presented. Depending on the geometry of the electrode system, a voltage pulse was 30–60 kV at a pulse FWHM duration of 50–200 ns. The measurement results revealed significant differences between the vibrational (2500–6000 K) and rotational (300–700 K) temperatures of the medium in a discharge, which are typical of nonequilibrium low-temperature plasma. It was shown that if the volume form of discharge is retained, the maximum electron density is (1.5 ± 0.2) × 1013 cm–3, which is comparable to the critical electron density for this type of discharge. The time of plasma existence is about 500 ns and corresponds to the time of existence of an electric field in the discharge region.