Growth of inhomogeneities in a pulsed self-sustained discharge

Holographic interferometry was used in a study of the dynamics of growth of perturbations in the medium of a pulsed self-sustained discharge with preionization by ultraviolet radiation. The discharge zone was probed along two mutually perpendicular directions. The inhomogeneities of the gaseous medium typical of such a discharge were classified. The sources of gasdynamic perturbation were identified and their temporal and spatial characteristics were determined. It was found that acoustic waves were generated because of a more rapid evolution of energy in side regions of the discharge and in the electrode layers. It was demonstrated experimentally that the periodic system of perturbations of the medium in the central part of the discharge gap was due to inhomogeneous preionization of the working zone due to the presence of a grid electrode in front of the ultraviolet radiation sources.