Program > Workshops

Workshops’ announcement

According to the conference style of GD conference series and regarding the registered delegates, some workshops will be organized. 4 delegates and topical leaders have been accepted to chair these workshops; you may find below a short description of each workshop given by the corresponding chair. The workshops are open to all delegates, the scheduled duration is about 1 hour and meeting rooms are available if some delegates would extend their discussion. If you have some suggestions or whishes about a workshop, you can contact its chair for now but e-mail.

Workshop 1: Properties of thermal and quasi-thermal plasmas

Chair: Dr Yann Cressault, yann.cressault@laplace.univ-tlse.fr

Monday, 17:45-18:45

In order to improve industrial processes using thermal and quasi-thermal plasmas, numerous models and experimental studies are developed. These works require the preliminary knowledge of properties such as number densities, transport coefficients or radiation. The workshop will give the opportunity to talk about the properties and to answer some questions:

1) How to obtain these properties by considering LTE or non LTE? The calculation methods used to determine transport and radiative properties are well-known supposing LTE whereas disagreements exist in the literature for non LTE problems.

2) How to validate these properties when they are calculated? Some discrepancies are often observed in papers concerning thermal conductivity or radiation for example, depending on the accuracy of the basic data. What are the consequences for industrial processes and how to validate them?

3) How to use the 2T properties in numerical modeling?

Workshop 2: Electrohydrodynamic effects produced by corona, barrier and surface discharges

Chair: Pr Eric Moreau, eric.moreau@univ-poitiers.fr

Monday, 17:45-18:45

Surface DBD and corona discharges have been particularly studied this last decade for their applications in aerodynamic flow control by plasma actuators. On one hand, surface DBD supplied by an ac sine high voltage produces an electrohydrodynamic force that results in an electric wind based wall jet. On the other hand, if the high voltage has a nanosecond repetitively pulsed waveform, the sudden gas heating at the dielectric wall results in a hydrodynamic pressure wave. Both mechanical phenomena can interact with incoming airflow in order to control it.

In the case of ac DBD, the time-averaged force is typically equal to 1 mN per consumed electrical watt and the electric wind velocity can reach about 10 m/s. The pressure gradient produced by a pulsed discharge is equal to a few kPa. Up to now, airflows up to about 100 m/s have been successfully manipulated.

The workshop will focus in particular on the performance of plasma actuators in quiescent air, on the plasma-flow interaction and on the mechanisms that result in flow control.

Workshop 3: Modeling of HV circuit breakers: where do we stand and what are the challenges

Chair: Dr Martin Seeger, martin.seeger@ch.abb.com

Tuesday, 17:45-18:45

In the recent meeting of the Current Zero Club (http://www.currentzeroclub.org/) in Suzhou/China, a discussion was started about the quality of modeling of the physical process in High Voltage SF6 circuit breakers. Discussed issues were for example:

What is the importance of Non-LTE effects?

How turbulence should be modeled?

When should 3D effects be modeled?

Material issues?

This discussion will be continued within a “gas inner circle” meeting at the GD2014, which is open to everybody who is interested in the topic.

Workshop 4: Major challenges in the diagnostics of non thermal plasma sources relevant for biomedical applications

Chair: Dr Eric Robert, eric.robert@univ-orleans.fr

Tuesday, 17:45-18:45

Following recent impressive demonstrations of non thermal plasma (NTP) effects in many biomedical applications -ranging from decontamination, sterilization, biomaterial processing, interaction with cells and living tissues-, there still exists today a large number of open and key questions dealing with the role of each plasma constituents, including electric field, energetic radiation and reactive species delivered during NTP treatments. Dealing with plasma jets, research works focus on their diagnostics and modeling, in most cases in situations rather challenging or inoperable through conventional measurement techniques: low density values, transient nature, strong quenching in atmospheric ambient air, influence of plasma jet environment on the discharge dynamics, extremely fast propagation, small-sized volume… Recent publications indicate that such diagnostics or modeling has to be considered not only for free jet expansion but more importantly in setups mimicking as much as possible real situations for plasma jet in use, i.e. with jet impinging on targets of various nature. Plasma propagation and reactive species generation in relevant setups together with the strong interplay between gas jets and plasmas are key issues to be addressed to understand the biological action of plasma and to optimize many biomedical applications.

Tentative non exhaustive topic list:

Non Thermal Plasma sources (RF/HF/AC/Pulsed, plasma jets, DBD, others NTP sources)

Plasma generation and propagation: inside tubes, in ambient air (plume)

streamers, ionization waves, surface discharge, ionization front and plasma tail

role of: dielectric confinement, photoionization, penning reactions, preionization

Plasma diagnostics

current, plasma power measurements

electronic density, reactive species measurements and modeling

Electric field measurement and modeling

gas jet/ plasma interaction: laminar/turbulent, gas jet bending/channeling

NTP sources in use:

Interaction of plasmas with targets

From gas phase to liquid chemistry

Plasmas in liquids…

We strongly invite any GD participants having interest in this front panel to suggest topics to be discussed next July and to send preliminary overview of their contribution (one paragraph text or maximum of 8 slides) to the chair: eric.robert@univ-orleans.fr