Flight and Wind-Tunnel Tests of Closed-Loop Active Flow Control

This paper presents a closed-loop active flow control strategy to reduce the velocity deficit of the wake of a compressor stator blade. The unsteady stator-rotor interaction, caused by the incoming stator wakes, generates fast changes of the rotor blade loading, affecting the stability and the performance of the overall compressor. Negative effects will be seen likewise when unsteady combustion concepts, such as a pulsed detonation, produce upstream disturbances. Furthermore, the periodic unsteady flow leads to additional undesired effects such as noise and blade vibrations. A controlled reliable manipulation of the stator wake is a way to handle these issues. Therefore, investigations on wake manipulation with trailing-edge blowing were carried out on a new low-speed cascade test rig. Detailed information about the wake profile is obtained by five-hole probe measurements in a plane downstream of the cascade for the natural and the actuated flow at a Reynolds number of 6×105. These measurements show a significant reduction of the wake velocity deficit for the investigated actuator geometry with an injection mass flow of less than 1% of the passage mass flow. Based on these results a position in the wake was chosen which is representative for the actuation impact on the velocity deficit. There, a hot-wire-probe measurement serves as the controlled variable. A family of linear dynamic black-box models was identified from experimental data to account for nonlinear and unmodelled effects. Static nonlinearitiy was compensated for by a Hammerstein model to reduce the model uncertainty and get a higher controller performance. To handle off-design conditions, a robust controller working in a range of Reynolds numbers from 5×105 to 7×105 was synthesized. The task of the controller is to rapidly regulate the controlled variable to a reference velocity by changing the blowing amplitude. The synthesized robust controller was successfully tested in closed-loop experiments with good results in reference tracking for pulse series up to 20 Hz. This translates into a much higher frequency when scaled to the dimension of a real machine.

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Suppression of Wind Tunnel Buffeting by Active Flow Control

10.4271/2004-01-0805 ◽

2004 ◽

Cited By ~ 5

Author(s):

Wilhelm von Heesen ◽

Matthias Höpfer

Keyword(s):

Wind Tunnel ◽

Flow Control ◽

Active Flow Control ◽

Active Flow

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Closed-Loop Active Flow Control of a Three-Dimensional Turret Wake

51st AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition ◽

10.2514/6.2013-394 ◽

2013 ◽

Cited By ~ 1

Author(s):

Patrick Shea ◽

Mark Glauser

Keyword(s):

Flow Control ◽

Closed Loop ◽

Active Flow Control ◽

Three Dimensional ◽

Active Flow

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Design of a Large Scale Vertical Stabilizer Wind Tunnel Model for Active Flow Control Research

Volume 5: 6th International Conference on Micro- and Nanosystems; 17th Design for Manufacturing and the Life Cycle Conference ◽

10.1115/detc2012-70197 ◽

2012 ◽

Author(s):

Glenn Saunders ◽

Edward Whalen ◽

Helen Mooney ◽

Sarah Zaremski

Keyword(s):

Wind Tunnel ◽

Flow Control ◽

Large Scale ◽

Active Flow Control ◽

Scale Model ◽

Tunnel Model ◽

Control Research ◽

Model Geometry ◽

Design Requirements ◽

Active Flow

The design, fabrication and installation of an approximately 1/6 scale model of an aircraft vertical stabilizer for research in Active Flow Control (AFC) is discussed. Highlighted are the unique design requirements of wind tunnel models, the specialized fabrication techniques employed to create them and the required close collaboration between industry, government and three academic institutions. The design of the model involves often competing constraints imposed by structural, instrumentation, aerodynamic, manufacturability and research-agenda considerations as well as cost and schedule. Instrumentation requires hundreds of pressure ports and six-axis force/torque sensing. Aerodynamic considerations necessitate high manufacturing precision, highly-skilled fabrication techniques and careful observance of model geometry throughout the design and fabrication processes. A scale model of a vertical stabilizer for AFC research was successfully designed, fabricated and deployed. The collaboratively designed model satisfies the structural, aerodynamic and research design constraints, and furthers the state of the art in Active Flow Control research.

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Closed-Loop Active Flow Control of a Three-Dimensional Turret Wake

AIAA Journal ◽

10.2514/1.j052810 ◽

2014 ◽

Vol 52 (10) ◽

pp. 2165-2175

Author(s):

Patrick R. Shea ◽

Mark N. Glauser

Keyword(s):

Flow Control ◽

Closed Loop ◽

Active Flow Control ◽

Three Dimensional ◽

Active Flow

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Correction: Towards Efficient 2-DOF LCO Control Using a Closed-loop Nonlinear Active Flow Control Technique

AIAA Scitech 2020 Forum ◽

10.2514/6.2020-1492.c1 ◽

2020 ◽

Author(s):

William MacKunis ◽

Vladimir V. Golubev ◽

Krishna Bhavithavya B. Kidambi ◽

Reda R. Mankbadi ◽

Oksana Stalnov

Keyword(s):

Flow Control ◽

Closed Loop ◽

Active Flow Control ◽

Control Technique ◽

Active Flow

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Numerical and Experimental Wind Tunnel and Flight Testing of Active Flow Control for Modified NACA 643-618 Airfoil

53rd AIAA Aerospace Sciences Meeting ◽

10.2514/6.2015-1705 ◽

2015 ◽

Cited By ~ 1

Author(s):

James Dianics ◽

Duncan Ohno ◽

Stefan Fuggmann ◽

Jonas Lay ◽

Daniel Heim ◽

...

Keyword(s):

Wind Tunnel ◽

Flow Control ◽

Active Flow Control ◽

Flight Testing ◽

Active Flow

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Fluidic actuators for separation control at the engine/wing junction

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-01-2017-0013 ◽

2017 ◽

Vol 89 (5) ◽

pp. 709-718 ◽

Cited By ~ 2

Author(s):

Philipp Schloesser ◽

Michael Meyer ◽

Martin Schueller ◽

Perez Weigel ◽

Matthias Bauer

Keyword(s):

Wind Tunnel ◽

Flow Control ◽

Flow Separation ◽

Mass Flux ◽

Large Scale ◽

Active Flow Control ◽

Wind Tunnel Test ◽

Local Flow ◽

Content Type ◽

Active Flow

Purpose The area behind the engine/wing junction of conventional civil aircraft configurations with underwing-mounted turbofans is susceptible to local flow separation at high angles of attack, which potentially impacts maximum lift performance of the aircraft. This paper aims to present the design, testing and optimization of two distinct systems of fluidic actuation dedicated to reduce separation at the engine/wing junction. Design/methodology/approach Active flow control applied at the unprotected leading edge inboard of the engine pylon has shown considerable potential to alleviate or even eliminate local flow separation, and consequently regain maximum lift performance. Two actuator systems, pulsed jet actuators with and without net mass flux, are tested and optimized with respect to an upcoming large-scale wind tunnel test to assess the effect of active flow control on the flow behavior. The requirements and parameters of the flow control hardware are set by numerical simulations of project partners. Findings The results of ground test show that full modulation of the jets of the non-zero mass flux actuator is achieved. In addition, it could be shown that the required parameters can be satisfied at design mass flow, and that pressure levels are within bounds. Furthermore, a new generation of zero-net mass flux actuators with improved performance is presented and described. This flow control system includes the actuator devices, their integration, as well as the drive and control electronics system that is used to drive groups of actuators. Originality/value The originality is given by the application of the two flow control systems in a scheduled large-scale wind tunnel test.

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