Steady and Unsteady compressible Reduced-Order Models of a Zero-Net Mass-Flux Synthetic Jet Actuator

A synthetic jet actuator is a zero-net mass-flux device that imparts momentum to its surroundings and has proved to be a useful active flow control device. Using the lattice Boltzmann method (LBM) with the Bhatnagar-Gross-Krook (BGK) collision models, a 3-D simulation of a synthetic jet with cylindrical cavity employing a sinusoidal velocity inlet boundary condition was conducted. The velocity distributions are illustrated and discussed, and the numerical results are validated against previous experimental data. The computed results show the ingestion and expulsion flow over one working cycle as well as the evolution of vortices important to the control of the separated shear layer. Zero-net mass-flux behavior is confirmed.

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Reduced-Order Models of Zero-Net Mass-Flux Jets for Large-Scale Flow Control Simulations

26th AIAA Applied Aerodynamics Conference ◽

10.2514/6.2008-6404 ◽

2008 ◽

Cited By ~ 1

Author(s):

Reni Raju ◽

Ehsan Aram ◽

Rajat Mittal ◽

Louis Cattafesta

Keyword(s):

Flow Control ◽

Mass Flux ◽

Large Scale ◽

Reduced Order Models ◽

Reduced Order ◽

Zero Net Mass Flux ◽

Large Scale Flow

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Aeroelastic Response of Airfoils Accounting for Synthetic Jet Actuation: Modeling and Comparison of CFD and Reduced Order Models

44th AIAA Aerospace Sciences Meeting and Exhibit ◽

10.2514/6.2006-1062 ◽

2006 ◽

Author(s):

Stephen Schober ◽

Pier Marzocca ◽

Valerio Viti ◽

Mostafa Abdalla

Keyword(s):

Synthetic Jet ◽

Reduced Order Models ◽

Aeroelastic Response ◽

Reduced Order

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Reduced Order Models for Synthetic Jet Actuators on a Lifting Surface for Optimization and Control

47th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference<BR> 14th AIAA/ASME/AHS Adaptive Structures Conference<BR> 7th ◽

10.2514/6.2006-1906 ◽

2006 ◽

Cited By ~ 3

Author(s):

Stephen Schober ◽

Pier Marzocca ◽

Roeland De Breuker ◽

Mostafa Abdalla

Keyword(s):

Synthetic Jet ◽

Reduced Order Models ◽

Reduced Order ◽

Synthetic Jet Actuators ◽

Lifting Surface ◽

Jet Actuators ◽

Optimization And Control ◽

And Control

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Transitory Behavior of Synthetic Jets

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2005-77010 ◽

2005 ◽

Cited By ~ 2

Author(s):

Michael Amitay ◽

Florine Cannelle

Keyword(s):

Reynolds Number ◽

Steady State ◽

Input Signal ◽

Mass Flux ◽

Reynolds Numbers ◽

Synthetic Jet ◽

Synthetic Jets ◽

Hot Wire ◽

Stroke Length ◽

Zero Net Mass Flux

The transitory behavior of an isolated synthetic (zero net mass flux) jet was investigated experimentally using PIV and hot-wire anemometry. In the present work, the synthetic jet was produced over a broad range of length- and time-scales, where three formation frequencies, f = 300, 917, and 3100Hz, several stroke lengths (between 5 and 50 times the slit width) and Reynolds numbers (between 85 and 408) were tested. The transitory behavior, following the onset of the input signal, in planes along and across the slit was measured. It was found that the time it takes the synthetic jet to become fully developed depends on the stroke length, formation frequency and Reynolds number. In general, the transients consist of four stages associated with the merging of vortices in both cross-stream and spanwise planes that grow in size, which lead to the pinch off of the leading vortex before the jet reaches its steady-state.

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Study of a Crossflow over a Zero-Net-Mass-Flux Synthetic Jet Driven by a Vibrating Diaphragm

Journal of Mechanics ◽

10.1017/jmech.2011.53 ◽

2011 ◽

Vol 27 (4) ◽

pp. 503-509 ◽

Cited By ~ 2

Author(s):

L.-Y. Tseng ◽

A.-S. Yang ◽

J.-C. Lin

Keyword(s):

Boundary Layer ◽

Flow Control ◽

Turbulent Flows ◽

Mass Flux ◽

Moving Boundary ◽

Active Flow Control ◽

Flow Characteristics ◽

Synthetic Jet ◽

Computational Domain ◽

Zero Net Mass Flux

ABSTRACTMiniature synthetic jet actuators are low operating power, zero-net-mass-flux and very compact devices which have demonstrated their capability in modifying the subsonic flow characteristics for boundary layer flow control. In order to improve the design active flow control systems, the present study aims to examine the formation and interaction of unsteady flowfield of a synthetic jet with external crossflow. In view of a single synthetic jet emitting into a turbulent boundary layer crossflow via a circular orifice, the theoretical model utilized the transient three-dimensional conservation equations of mass and momentum for compressible, turbulent flows with a negligible temperature variation over the computational domain. The motion of a movable membrane plate was also treated as the moving boundary by prescribing the displacement on the plate surface. The predictions by the computational fluid dynamics (CFD) software ACE+®were compared with the measured transient phase-averaged velocities in literature for code validation. The predictions showed the time evolution of the large vortical structure originating from the jet orifice and its successive interaction with the crossflow to change the flow structure inside the boundary layer.

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Reduced Order Nonlinear Navier Stokes Models for Synthetic Jets

Volume 7B: 17th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc99/vib-8065 ◽

1999 ◽

Author(s):

Othon K. Rediniotis ◽

Andrew J. Kurdila

Keyword(s):

Numerical Study ◽

Control Strategies ◽

Order Reduction ◽

Synthetic Jet ◽

Reduced Order Models ◽

Loop Control ◽

Reduced Order ◽

Synthetic Jet Actuators ◽

Jet Actuators ◽

Reduction Methods

Abstract While the potential for the use of synthetic jet actuators to achieve flow control has been noted fro some tme, most studies of these devices have been empirical or experimental in nature. Several technical issues must be resolved to achieve rigorous, model-based, closed loop control methodologies for this class of actuator. The goal of this paper is consequently two-fold. First, we seek to derive and evaluate model order reduction methods based on proper orthogonal decomposition that are suitable for synthetic jet actuators. Secondly, we seek to derive rigorously stable feedback control laws for the derived reduced order models. The readability of the control strategies is discussed, and a numerical study of the effectiveness of the reduced order models are summarized.

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Development of a Variable Diameter Synthetic Jet Actuator

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2014-36936 ◽

2014 ◽

Cited By ~ 1

Author(s):

Spencer O. Albright ◽

Stephen A. Solovitz

Keyword(s):

Synthetic Jet ◽

Pneumatic Cylinder ◽

Synthetic Jet Actuator ◽

Variable Diameter ◽

Image Velocimetry ◽

Flow Speeds ◽

Exit Speed ◽

Zero Net Mass Flux ◽

Piston Stroke ◽

Oscillating Motion

Synthetic jet actuators use oscillating motion near a fixed orifice to produce a net axial momentum flux with zero net mass flux. Through strategic application, these devices can provide flow control, propulsive thrust, and impingement cooling. To improve this performance, a new actuator has been designed with a variable orifice size, which can potentially increase exit flow speeds. The jet is generated using a pneumatic cylinder, which is oscillated linearly near an orifice. The opening consists of a camera aperture, whose diameter can decrease by a factor of 18 with the aid of a second pneumatic cylinder. The system is capable of operating at frequencies up to 5 Hz while maintaining full piston stroke, and the phase between the piston and orifice motion can be varied from 0 to 180 degrees. The flow structure is investigated using phase-locked particle image velocimetry (PIV), which shows that simultaneous constriction of the exit can substantially increase the exit speed. The initial design is used with air flow but will be extended to water applications in the future.

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