Effects of high-speed airflows on a surface dielectric barrier discharge

Abstract

A detailed study of the interaction between high-speed gas flows and surface dielectric barrier discharges (DBD) is presented. In the present paper, it is demonstrated that a DBD can be sustained in transonic airflows, up to isentropic Mach numbers of 1.1. The plasma is characterized electrically, as well as optically with a CCD camera and a photomultiplier tube. Different airflow velocities, plasma excitation frequencies and voltages are investigated. The airflow has a significant influence on the plasma characteristics: the glow component is reduced, the discharge becomes more filamentary and most importantly, the light emission duration from individual microdischarges is reduced by more than a factor of ten at high flow velocities. Large edge effects play a key role in the interaction between the flow and the plasma. These results offer new perspectives for the use of dielectric barrier discharges in transonic and supersonic gas flows and their applications to airflow control and to plasma-assisted combustion.

On the Measurement of N2(A3Σ u + ) Metastable in N2 Surface-Dielectric Barrier Discharge at Atmospheric Pressure

“…On contrary, in Ref. [17] it was observed in a similar discharge that plasma emission had a predominant filamentary and a predominant diffuse/glow discharge character during positive and negative current polarity respectively. This observation agrees with our plasma emission distribution in the voltage cycle.…”

“…Typically in surface-DBDs the electrodes are deposited on a dielectric slab or embedded in it, and the discharge develops as a thin layer over the dielectric surface [12][13][14][15]. Microscopic optical investigations of such discharges are difficult and scarce, although surface-DBDs have been investigated in connection with O 3 generation and surface treatment, and actually are receiving a growing interest for their possible aerospace application as actuator devices for flow control [15][16][17][18][19]. Therefore the N 2 (A) issue and its relevance in the development of such discharges deserves to be focused.…”

“…Very high concentrations (*5 9 10 14 cm -3 ) of N 2 (A 3 R u + ) were estimated in the case of filamentary streamers produced in pure nitrogen by a pulsed positive corona discharge [10]. Analogously, a high density of N 2 (A) may be expected in the case of filamentary N 2 surface barrier discharges such as to be very effective in affecting the discharge properties [17]. The issue of the role of metastable in surface DBD is hence relevant as for volume DBD.…”

Online-characterization of dielectric barrier discharge plasma actuators for optimized efficiency of aerodynamical flow control applications

“…First (qualitative) reports by Pavon et al [7] indicated the [2,[6][7][8] the present manuscript addresses the above mentioned discrepancies with a new online diagnosis tool for DBDs. Such a monitoring system is essential for optimal flow-control using DBD plasma actuators, since it provides the required information to characterize and quantify the impact of fluctuating or transient airflow conditions on the plasma-actuator performance during operation.…”

Understanding SDBD Actuators: An Experimental Study on Plasma Characteristics

“…At higher flow velocities, this equivalent wall-jet does not seem to produce significant effects. In a previous study at EPFL, Pavon et al 3,4 investigated the interaction between an AC-DBD actuator mounted on a NACA 3506 profile in transonic flow, where no noticeable effect of the actuator on the shock wave buffeting and strength was observed. However, a strong effect on the discharge plasma state was produced with increasing speeds.…”