Hydrodynamical simulation of the electric wind generated by successive streamers in a point-to-plane reactor

Abstract

An electrical corona discharge at atmospheric pressure in positive point-to-plane configuration creates an electric wind from the point to the plane which, within a few seconds, generates an axisymmetrical vortex in a closed cylindrical vessel (ring vortex). A first model for the establishment of this vortex was recently published and our study is an evolution based on an improved physical model. It does not include any empirical time scaling parameter, and takes into account the successive ionizing fronts as a varying electrical force due to the propagation of a sharp electrical field maximum acting on the space charge distribution along the interelectrode gap. After the front propagation (50 ns), the remaining positive ions drift (during 100 µs) in the slowly restoring electric field. Numerical simulations show that the very first streamers and remaining positive ions rapidly push the gas along the very narrow discharge volume, creating a small ring vortex at the cathode around the discharge axis. The following ones have a cumulative effect leading to the enlargement of the vortex. In a few seconds, a quasi-stationary distribution is obtained, which is very close to the experimentally observed steady state.

Plasma–Gas Flow Interaction of a Discharge Normal to a Bluff Body Wake

“…The reason for this deflection is the electric wind, directed from the anode to the cathodic wall, created by the repetitive streamers. The air motion originated in this way is similar to the one created by a stable corona discharge [11], [32], and in the absence of the axial airstream it should give rise to a large region of recirculating flow.…”

Nonequilibrium Plasma Aerodynamics

“…AC discharges and pulsed discharges with significant bias situated in between of these two limiting cases. Presently, the possibility of gas acceleration reaching a velocity up to nearly 10 m/s has been shown with the help of positive corona [Loiseau et al, 2002;Zouzou et al, 2006;Rickard et al, 2006]. It should be noted that the nature of gas acceleration is the same in all cases.…”

Numerical Simulation of Influence of Reduced Electric Fields on NOx Removal in N2/O2/H2O/CO2 Mixture

“…We notice that the evolution depends strongly on the increase of reduced electric field. Generally, the fractions of the energy transferred from charged to neutral particles via elastic and inelastic processes are given from a Boltzmann equation solution [29]. So, the fraction of energy lost during elastic, excitation and ionization processes in the same gas mixture depends on the electric reduced field.…”

“…The motion of a fluid induced by an electrical discharge is cited as an electrical wind or ion wind. It was demonstrated long ago and widely studied in the case of a corona discharge between a tip and a plane [27][28][29][30]. Generally, the charged particles created in the inter electrode space are accelerated by the electric field E. It is well known that all electrical proprieties are depending on the reduced field E/N, where N is the density of neutral gas and E the electric field [31][32][33], and increase the internal energy of the neutral gas.…”