Searched for: author:"Kotsonis, M."
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Tol, H.J. (author), Kotsonis, M. (author), de Visser, C.C. (author)
This paper investigates the use of point wall pressure measurements for output feedback control of Tollmien–Schlichtingwaves in Falkner–Skan boundary layers.Anewapproach is presented for input–outputmodeling of the linear dynamics of the fluid system and the integration withH2∕Linear Quadratic Gaussian reduced-order control design. The pressure...
journal article 2019
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Zong, H. (author), Kotsonis, M. (author)
, and the peak lift...
journal article 2018
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Kurelek, J.W. (author), Kotsonis, M. (author), Yarusevych, S. (author)
Transition and flow development in a separation bubble formed on an airfoil are studied experimentally. The effects of tonal and broadband acoustic excitation are considered since such acoustic emissions commonly result from airfoil self-noise and can influence flow development via a feedback loop. This interdependence is decoupled, and the...
journal article 2018
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Groot, K.J. (author), Serpieri, J. (author), Pinna, Fabio (author), Kotsonis, M. (author)
A combined experimental and numerical approach to the analysis of the secondary stability of realistic swept-wing boundary layers is presented. Global linear stability theory is applied to experimentally measured base flows. These base flows are three-dimensional laminar boundary layers subject to spanwise distortion due to the presence of...
journal article 2018
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Serpieri, J. (author), Kotsonis, M. (author)
In this study, experiments are performed towards the identification and measurement of unsteady modes occurring in a transitional swept wing boundary layer. These modes are generated by the interaction between the primary stationary and travelling cross-flow instabilities or by secondary instability mechanisms of the stationary cross-flow...
journal article 2018
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Michelis, Theodorus (author), Yarusevych, S. (author), Kotsonis, M. (author)
This work investigates the three-dimensional, spatio-Temporal flow development in the aft portion of a laminar separation bubble. The bubble is forming on a flat plate geometry, subjected to an adverse pressure gradient, featuring maximum reverse flow of approximately 2Â % of the local free-stream velocity. Time-resolved velocity measurements...
journal article 2018
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Yadala Venkata, Srikar (author), Hehner, M.T. (author), Serpieri, J. (author), Benard, Nicolas (author), Dörr, Philipp C. (author), Kloker, Markus J. (author), Kotsonis, M. (author)
Control of laminar-to-turbulent transition on a swept-wing is achieved by base-flow modification in an experimental framework, up to a chord Reynolds number of 2.5 million. This technique is based on the control strategy used in the numerical simulation by Dörr & Kloker (J. Phys. D: Appl. Phys., vol. 48, 2015b, 285205). A spanwise uniform...
journal article 2018
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Serpieri, J. (author), Yadala Venkata, Srikar (author), Kotsonis, M. (author)
In the current study, selective forcing of cross-flow instability modes evolving on a swept wing at is achieved by means of spanwise-modulated plasma actuators, positioned near the leading edge. In the perspective of laminar flow control, the followed methodology holds on the discrete roughness elements/upstream flow deformation (DRE/UFD)...
journal article 2017
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Zong, H. (author), Kotsonis, M. (author)
The performance of a two–electrode plasma synthetic jet actuator (PSJA) is investigated for a wide range of dimensionless actuation frequencies (f*) using high-speed phase-locked Particle Imaging Velocimetry (PIV) measurements. The jet-induced velocity fields in the axisymmetric plane are measured during both...
journal article 2017
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Zong, H. (author), Kotsonis, M. (author)
journal article 2017
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Tol, H.J. (author), Kotsonis, M. (author), de Visser, C.C. (author), Bamieh, B. (author)
A new framework is presented for estimation and control of instabilities in wall-bounded shear flows described by the linearised Navier-Stokes equations. The control design considers the use of localised actuators/sensors to account for convective instabilities in an optimal control framework. External sources of disturbances are assumed to...
journal article 2017
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Michelis, Theodorus (author), Yarusevych, S. (author), Kotsonis, M. (author)
The spatial and temporal response characteristics of a laminar separation bubble to impulsive forcing are investigated by means of time-resolved particle image velocimetry and linear stability theory. A two-dimensional impulsive disturbance is introduced with an alternating current dielectric barrier discharge plasma actuator, exciting...
journal article 2017
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Zong, H. (author), Kotsonis, M. (author)
This paper experimentally investigates the interaction between a plasma synthetic jet (PSJ) and a subsonic turbulent boundary layer (TBL) using a hotwire anemometer and phase-locked particle imaging velocimetry. The PSJ is interacting with a fully developed turbulent boundary layer developing on the flat wall of a square wind tunnel section...
journal article 2017
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Zong, H. (author), Kotsonis, M. (author)
This study experimentally investigates the influence of exit orifice shape on the performance characteristics of a three-electrode plasma synthetic jet actuator. High-speed Schlieren imaging system and phase-locked two-component PIV measurements are used for flowfield characterisation in quiescent conditions. Two actuator configurations with...
journal article 2017
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Yarusevych, S. (author), Kotsonis, M. (author)
This work examines the effect of local active flow control on stability and transition in a laminar separation bubble. Experiments are performed in a wind tunnel facility on a NACA 0012 airfoil at a chord Reynolds number of 130 000 and an angle of attack of 2 degrees. Controlled disturbances are introduced upstream of a laminar separation...
journal article 2017
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Serpieri, J. (author), Kotsonis, M. (author)
is presented. Linear stability theory is applied for preliminary estimation of the flow stability while surface flow visualisation using fluorescent oil is...
journal article 2016
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Zong, H. (author), Kotsonis, M. (author)
A simplified model is established to estimate the jet exit density variation of a plasma synthetic jet actuator (PSJA) driven by a capacitive arc discharge. This model, in conjunction with phase-locked planar particle imaging velocimetry (PIV) measurements, enables the calculation of jet mechanical energy for different operating conditions....
journal article 2016
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Zong, H. (author), Kotsonis, M. (author)
An experimental characterisation study of a large-volume three-electrode plasma synthetic jet actuator (PSJA) is presented. A sequential discharge power supply system is used to activate the PSJA. Phase-locked planar particle image velocimetry (PIV) and time-resolved Schlieren imaging are used to characterise the evolution of the induced flow...
journal article 2016
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Tol, H.J. (author), de Visser, C.C. (author), Kotsonis, M. (author)
A new methodology is presented for model reduction of linear parabolic partial differential equations (PDEs) on general geometries using multivariate splines on triangulations. State-space descriptions are derived that can be used for control design. This method uses Galerkin projection with B-splines to derive a finite set of ordinary...
journal article 2016
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Correale, G. (author), Winkel, R. (author), Kotsonis, M. (author)
An experimental study aimed at the characterization of energy deposition of nanosecond Dielectric Barrier Discharge (ns-DBD) plasma actuators was carried out. Special attention was given on the effect of the thickness and material used for dielectric barrier. The selected materials for this study were polyimide film (Kapton), polyamide based...
journal article 2015
Searched for: author:"Kotsonis, M."
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