al10

Ignition of Lean Air / Hydrocarbon Mixtures at Low Temperature by a Single Corona Discharge Nanosecond Pulse

Auteurs: 

S. Bentaleb, N. Blin-Simiand, P. Jeanney, L. Magne, N. Moreau, S. Pasquiers, P. Tardiveau (Université Paris-Sud and CNRS Université Paris-Saclay)

A great number of experimental studies have demonstrated that non-thermal plasmas produced by high voltage pulse discharges, running at a given pulse repetition frequency, are able to ignite air / hydrocarbon mixtures at a low initial temperature and atmospheric pressure. In this paper, we show that ignition can also be achieved using a single nanosecond pulse corona discharge generated under a very strong overvoltage. Experiments were conducted in air / propane and air / n-heptane mixtures.

Experiments on Plasma-Assisted Combustion in a Supersonic Flow: Optimization of Plasma Position in Relation to the Fuel Injector

Auteurs: 

K.V. Savelkin, D.A. Yarantsev (Russian Academy of Sciences)
S.B. Leonov (Russian Academy of Sciences) (University of Notre Dame)

The results of an experimental study of plasma-induced ethylene ignition and flameholding in a supersonic model combustor are presented in the paper. The experimental combustor has a cross-section of 72 mm (width) x 60 mm (height) and length of 600 mm. The fuel is directly injected into the supersonic airflow through wall orifices.

Mechanisms of Ethylene Flame Propagation Enhancement by O₂(a¹Δg)

Auteurs: 

T. Ombrello (U.S. Air Force Research Laboratory)
N. Popov (Moscow State University)

Recently estimated and updated quenching rates of O2(a1Δg) by H and H2 have been added to a known and validated combustion mechanism to predict enhancement of C2H4 flame propagation in the presence of O2(a1Δg).

Applications of Dielectric Barrier Discharges and Plasma Synthetic Jet Actuators at ONERA

Auteurs: 

F. Chedevergne, G. Casalis, O. Léon, M. Forte, F. Laurendeau, N. Szulga, O. Vermeersch, E. Piot (ONERA)

This paper focuses on two plasma actuators, developed at ONERA: the DBD actuator (Dielectric Barrier Discharge) and the PSJ actuator (Plasma Synthetic Jet). At the DMAE (Modeling for Aerodynamics and Energetics Department), DBD actuation is investigated for laminar/transition purposes. The results presented deal with 2D configurations including both experimental and modeling works.

Numerical Modeling of Dielectric Barrier Discharge Based Plasma Actuators for Flow Control: the COPAIER/CEDRE Example

Auteurs: 

G. Dufour, F. Rogier (ONERA)

Numerical simulation of active flow control using plasma actuators is dependent upon the development of models accounting for the effects of the actuators on the flow. These can be obtained either by using experimental results coupled with strong assumptions regarding the plasma force distribution, or through numerical simulation. The objective of this paper is to investigate the characteristics of DBD plasma source terms obtained using direct numerical simulation.

Plasmas for High Speed Flow Control

Auteurs: 

R. Joussot, S. Coumar, V. Lago (ICARE, CNRS, Orléans)

This paper presents experimental activities focused on supersonic flow control with plasma and MHD actuators. This work is carried out at ICARE, a laboratory located at the CNRS Campus in Orléans. The study of aerothermodynamic physics, one of the research fields of ICARE, is conducted with the experimental platform FAST consisting of three supersonic/hypersonic wind tunnels involved in aerothermodynamic testing for hypersonic flight and space technology.

Numerical Simulations on the Effect and Efficiency of Long Linear Energy Deposition Ahead of a Supersonic Blunt Body: Toward a Laser Spike

Auteurs: 

P.-Q. Elias (ONERA)

The effect of single or repetitive linear energy depositions in front of a supersonic blunt body is computed using the CEDRE flow solver. The CFD Code models the effect of a laser-induced energy deposition, as obtained for example using the long filaments created by a femtosecond laser. Single energy depositions show that significant transient drag reductions are obtained, due to the interaction of the heated core, created by the energy release, with the bow shock.

A Short Review of Microwave and Laser Discharges for Supersonic Flow Control

Auteurs: 

D. Knight (Rutgers, The State University of New Jersey)

Energy deposition by electromagnetic discharge (e.g., arc, laser, microwave) is an emerging field of research in flow and flight control. Major advantages of this approach include fast response time, capability for customization of discharge, and offbody modification of the flow. Recent computational and experimental research in energy deposition are described and future needs identified.

Plasma Aerodynamics: Current Status and Future Directions

Auteurs: 

J. Poggie (US Air Force Research Laboratory)
T. McLaughlin (US Air Force Academy)
S. Leonov (The Ohio State University)

Plasma aerodynamics can trace its origin to the beginning of the space age, and in particular to a time when designers realized that plasmas could have a significant influence on reentry flows. From the 1950s to the 1970s, there was considerable work on magnetohydrodynamic reentry systems and related technology. The recent resurgence in the field was stimulated by the disclosure of the Soviet AJAX vehicle concept in the mid-1990s.

Plasmas for Aeronautics

Auteurs: 

Denis Packan (ONERA)

The potential of plasmas for aerodynamics and combustion has been known for many years, but a dedicated research domain has only started to significantly develop over the past 20 years. Based either on new technological advances, on enhanced numerical capabilities, or on new needs created by the aeronautical industry’s quest for higher performance, the development of plasma actuators has now reached a point where an industrial application is within grasp.