Airflow control by non-thermal plasma actuators

TLDR

Active flow control, especially using plasma‑based devices, is gaining importance in aeronautics due to its robustness, simplicity, low power consumption, and ability for real‑time high‑frequency control. This review surveys worldwide research on non‑thermal plasma actuators from their origins to the present. The review is organized into two parts: the first examines the electric wind generated by surface non‑thermal plasma actuators in atmospheric air, and the second surveys their application for active airflow control. Electric wind can reach 8 m s⁻¹ at 0.5 mm from the wall, and plasma actuators achieve efficient control of low‑velocity subsonic flows (U∞ ≤ 30 m s⁻¹, Re ≈ 10⁵) with promising performance at higher velocities.

Abstract

Active flow control is a topic in full expansion due to associated industrial applications of huge importance, particularly for aeronautics. Among all flow control methods, such as the use of mechanical flaps, wall synthetic jets or MEMS, plasma-based devices are very promising. The main advantages of such systems are their robustness, simplicity, low power consumption and ability for real-time control at high frequency. This paper is a review of the worldwide works on this topic, from its origin to the present. It is divided into two main parts. The first one is dedicated to the recent knowledge concerning the electric wind induced by surface non-thermal plasma actuators, acting in air at atmospheric pressure. Typically, it can reach 8 m s−1 at a distance of 0.5 mm from the wall. In the second part, works concerning active airflow control by these plasma actuators are presented. Very efficient results have been obtained for low-velocity subsonic airflows (typically U∞ ≤ 30 m s−1 and Reynolds number of a few 105), and promising results at higher velocities indicate that plasma actuators could be used in aeronautics.