Mapping the electric field vector of guided ionization waves at atmospheric pressure

Abstract

In this study, the dynamic of guided ionization wave (IW) generated by an atmospheric pressure plasma jet (APPJ) device operating in helium is experimentally investigated. The present work focuses on the properties of the intense electric field (EF) driving the IW. Taking advantages of APPJs to produce guided and reproducible IWs, the induced EF vector is characterized spatially and temporally along the direction of propagation. With this approach, EF vector mapping of guided IWs have been measured and documented for the first time. In the first part, the propagation within a glass tube of the first IW is investigated. Under the present conditions, a second guided IW is observed and propagates, leading to the formation of a guided streamer. The EF due to transient charge deposited on the wall surface is observed, particularly at the end of the tube. In the second part, one reports on the EF vector mapping under a dielectric substrate in contact with guided IWs. EF strength up to 55 kV/cm has been measured and corroborates prior results from predictive numerical simulations. Intriguing configurations of the EF lines will be of significant interest to validate theoretical models in order to refine the non-equilibrium plasma chemistry kinetics. Furthermore, this preliminary work provides important insights into various applications involving IW driven discharges such as liquid activation, environmental treatments, plasma medicine, active flow control and plasma agriculture.

Reply to ‘Commentary on Mapping the electric field vector of guided ionization waves at atmospheric pressure, (2020) Plasma Res. Express 2 025014)’

“…Additionally, the external EF is a very sensitive quantity which does not require a direct interaction with a grounded target to be significantly affected. For instance, the data found in appendix of the PhD dissertation of Darny, T. (pages 256-258) and presented in the top left corner graph on page 257 exhibits a shape which recalls more the figure 2 of the original article [2] than the curve to be claimed in the Comment. The electric field is acting ahead of the IW propagation; this means that there is no need to have the IW directly in contact with the grounded plate to already induce a modification of the electric field and there is more research needed on this issue.…”

“…The Comment by Dozias S., Pouvesle J.-M. and Robert E. [1] raises concerns about the consistency of the experimental investigation of electric field (EF) distribution induced by guided ionization waves in Helium at atmospheric pressure [2]. With all due respect to the opinion of the authors, the claims in the Comment -namely that the results are wrong and inconsistent -seem to be invalid.…”

“…Firstly, the authors seem to be confused with the meaning of secondary ionization wave (SIW) as they correlate it to their own works. In [2], the SIW is produced not because of the impingement of the IW onto a grounded target, but because of a rapid change of the applied potential at the electrode as shown in [3,4,5] on the total current evolution curve. Thus, this is not to be compared with so-called "rebound".…”

Advances on aerodynamic actuation induced by surface dielectric barrier discharges

“…Authors have also assessed electro-optic sensors, based on Pockels effect, as tools to measure the real-time evolution of the electric field in non-equilibrium plasma formed in air and other gasses [25,[106][107][108], accurately obtaining even two electric field components simultaneously. The presence of the probe does not seem alter the electric field under study due to the small size and fully dielectric structure composed of a cylindrical isotropic birefringent crystal and a laser beam guided through an optic fiber.…”

“…The presence of the probe does not seem alter the electric field under study due to the small size and fully dielectric structure composed of a cylindrical isotropic birefringent crystal and a laser beam guided through an optic fiber. A disadvantage of this method is that it is not suitable for the measurement of a static electric field [107,108]. Most recently, the technique known as electric-fieldinduced second harmonic generation or E-FISH [109, 110], was developed at Princeton University for remote optical measurements of electric fields in gases and plasmas [111,112].…”