Nanosecond Dielectric Barrier Discharge Plasma Actuator Flow Control of Compressible Dynamic Stall
Abstract
Dynamic stall is a performance-limiting phenomenon experienced by rotorcraft in directional and maneuvering flight. Dynamic stall occurs on the retreating blade due to the high angles of attack that are experienced by the blades. Increasing the angle of attack is required to overcome the asymmetry of lift across the rotor disk that is a result from the velocity disparities between the advancing and retreating blade. This works sets out to study and improve the performance of a dynamically pitching NACA 0015 airfoil. The airfoil is subjected to both an incompressible and compressible flow field to simulate the dynamics of a rotor blade with cyclic pitching. In this experimental investigation of dynamic stall flow control, the effectiveness of nanosecond dielectric barrier discharge (NS-DBD) plasma actuation will be evaluated as a means to exert control authority. The NS-DBD plasma actuation is generated by a high-voltage magnetic compression pulsed power supply that was designed and built at The Ohio State University. To measure the influence of plasma actuation on the flow, surface pressures on the airfoil were measured through discrete pressure taps located on both the suction and pressure surfaces. The surface pressures are used to calculate the lift and moment during the dynamic pitching cycle. To visualize the compressibility effects in the outer flow, shadowgraph imagery was used to capture features in the flow around the leading edge of the test article.Tests were conducted at static and oscillating angles of attack at both Mach 0.2 and 0.4, and Reynolds numbers of 1.2 million and 2.2 million respectively. Pitch oscillations were conducted at reduced frequencies of 0.05 (k = 0.05). Actuation frequencies varied from non-dimensional frequencies (F+) of 0.78 to 6.09.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 06, 2015
- Accession Number
- AD1053913
Entities
People
- M. Frankhouser
Organizations
- Ohio State University