Abstract: | A one-dimensional self-consistent fluid numerical model was developed to study the ignition
characteristics of a pulse-modulated (PM) radio-frequency (RF) glow discharge in atmospheric
helium assisted by a sub-microsecond voltage excited pulsed discharge. The temporal evolution
of discharge current density and electron density during PM RF discharge burst was investigated
to demonstrate the discharge ignition characteristics with or without the pulsed discharge. Under
the assistance of pulsed discharge, the electron density in RF discharge burst reaches the
magnitude of 1.87×1017 m?3 within 10 RF cycles, accompanied by the formation of sheath
structure. It proposes that the pulsed discharge plays an important role in the ignition of PM RF
discharge burst. Furthermore, the dynamics of PM RF glow discharge are demonstrated by the
spatiotemporal evolution of the electron density with and without pulsed discharge. The spatial
profiles of electron density, electron energy and electric field at specific time instants are given to
explain the assistive role of the pulsed discharge on PM RF discharge ignition. |