Session: 11-13-01: Fluids and Public Health and Medicine / Industrial Flows

Paper Number: 168237

Voltage – Current Characterization of a Sliding DBD Plasma Actuator During Impact of Water Droplet 

Three-electrode dielectric barrier discharge (DBD) actuators are an advanced form of plasma generators used to create a continuous sheet of non-thermal plasma, commonly referred to as sliding plasma (SP-DBD). These actuators are particularly useful in a variety of applications where uniform plasma coverage is required over a large surface area. The design of a standard SP-DBD actuator comprises three electrodes arranged in a specific configuration to achieve a stable and widespread plasma discharge.

In a typical SP-DBD actuator, two of the electrodes are exposed and positioned parallel to each other. One of these electrodes, referred to as electrode 1, is supplied with a high alternating current (AC) voltage, while the other exposed electrode, known as electrode 3, is connected to a high direct current (DC) voltage of negative polarity. Sandwiched between these two exposed electrodes is electrode 2, which is encapsulated within a dielectric material and grounded. This dielectric barrier plays a crucial role in stabilizing the plasma and influencing the characteristics of the discharge.

Unlike traditional two-electrode DBD actuators, which often suffer from limited plasma coverage—typically restricted to a maximum range of about 2 cm—SP-DBD actuators exhibit a more uniform plasma distribution across the entire gap between the two exposed electrodes. Additionally, in the conventional two-electrode configuration, plasma intensity diminishes significantly as the distance from the emitting electrode increases. In contrast, the three-electrode setup allows for sustained plasma activity across a larger area, making it advantageous for various plasma-assisted processes.

During the operation of an SP-DBD actuator, a dynamic process of charge accumulation and transport occurs. Charged particles generated in the plasma accumulate at the edge of electrode 1 and are then carried across the discharge gap toward electrode 3. This movement of charged species plays a fundamental role in the properties and behavior of the plasma sheet, influencing its stability, intensity, and interaction with external elements.

In our previous research, we investigated the impact of a water droplet on the sliding plasma to analyze the dynamic response of both the droplet and the plasma actuator. This study focused on understanding the complex interactions between the droplet and the plasma field, including the associated thermal effects. It was observed that several intricate and fascinating phenomena take place during these interactions. For example, plasma streamers were seen forming between the droplet and either of the exposed electrodes, and in some instances, both electrodes simultaneously. Furthermore, arcing between the electrodes was also detected, indicating the presence of intense localized electric fields.

To gain deeper insight into these complex interactions, our current research aims to perform high-frequency measurements of voltage and current passing through both exposed electrodes. These electrical measurements will be coupled with high-speed imaging to capture the rapid events occurring during the water-plasma interaction. By employing these advanced diagnostic techniques, we seek to achieve a more comprehensive understanding of the fundamental processes governing plasma formation, charge transport, and energy dissipation in SP-DBD actuators, particularly in the presence of water droplets. Such knowledge is crucial for optimizing plasma-based technologies for applications in areas such as fluid dynamics control, surface treatment, and biomedical engineering.

Presenting Author: Yang Liu The City College of New York

Presenting Author Biography: Dr. Yang Liu is an Assistant Professor of Mechanical Engineering at the City College of New York. His current research interests include multiphase flow and heat transfer in additive manufacturing, flow-structure interactions in compressible flow, high-speed multiphase interactions, aircraft icing physics and anti-/de-icing technologies, and unsteady multiphase flow in energy devices. Dr. Liu has published 1 book, 2 book chapters, 40 peer-reviewed journal papers, and more than 60 conference papers in the field of thermal fluids.

Authors:

Petr Lelikov City College of New York
Jorge Ahumada Lazo City College of New York
Yang Liu The City College of New York