Searched for: subject%3A%22flutter%22
(1 - 20 of 27)

Pages

List view
Grid view
document
de Boer, Stefan (author)
The flight tests which are part of the certification procedure that prove that no flutter occurs within the flight envelope are fraught with risk. To reduce the risk, numerous numerical analyses, wind tunnel and ground tests are performed, which together with the flight tests result in a long and costly test programme.<br/><br/>To reduce the...
master thesis 2023
document
Schildkamp, R.R.M. (author), Chang, J. (author), Sodja, J. (author), De Breuker, R. (author), Wang, Xuerui (author)
This paper proposes an incremental nonlinear control method for an aeroelastic system’s gust load alleviation and active flutter suppression. These two control objectives can be achieved without modifying the control architecture or the control parameters. The proposed method has guaranteed stability in the Lyapunov sense and also has...
journal article 2023
document
Castillo Capponi, Diego (author)
In the last few years, a new aircraft configuration has been developed: the electric Vertical Take-off/Landing aircraft (eVTOL). To improve aircraft efficiency, structures are lighter and more flexible. Due to the structure's flexible nature and the use of propellers for propulsion, eVTOL are prone to whirl flutter, which consists of a dynamic...
master thesis 2022
document
Aditya, Abhyuday (author)
Supersonic flows cause thin panels to flutter, which is characterized by high-amplitude self-sustained oscillations, increasing the risk of fatigue failure. Flutter is known to be exacerbated when a shock wave impinges on the panel, creating a shock wave/boundary-layer interaction (SWBLI) which promotes separation of flow and leads to increased...
master thesis 2022
document
Mathijssen, Lucas (author)
Supersonic panel flutter is a self-excited vibration, where energy is transferred into thin flexible panels, such as skin panels in supersonic vehicles, from the (supersonic) flow around them, which can lead to their rapid fatigue failure. Relevant examples of this include the failure of skin panels in the X-15 vehicle, or violent oscillations...
master thesis 2022
document
Schildkamp, R.R.M. (author), Chang, J. (author), Sodja, J. (author), De Breuker, R. (author), Wang, Xuerui (author)
This paper proposes an incremental nonlinear control method for aeroelastic sys- tem gust load alleviation and active flutter suppression. These two control objectives can be achieved without modifying the control architecture or the control parameters. The proposed method has guaranteed stability in the Lyapunov sense and also has robustness...
conference paper 2022
document
Bunk, Yannick (author)
The development of a high-fidelity fluid-structure interaction tool for the simulation of aircraft flight dynamics in the subsonic flow regime is presented. The tool combines a high-fidelity large-eddy simulation code with an immersed boundary method, a multibody solver and a loose coupling scheme between fluid and solid. The development of the...
master thesis 2022
document
Wang, Z. (author), Liu Xu, Vanessa Q. (author), De Breuker, R. (author)
In the development of electric aircraft, the use of distributed electric propulsion introduces a potential occurrence of propeller whirl flutter, which needs to be taken into account for wing structural design. To this end, this work extends an in-house aeroelastic optimization tool by means of including a post-processing procedure on whirl...
conference paper 2022
document
Quesada Allerhand, Pedro (author)
The vibration of panel structural elements immersed in a supersonic flow is a poorly understood fluid-structure interaction (FSI) that can affect the performance and structural integrity of supersonic aircraft and spacecraft systems. These adverse effects are further amplified when a shock-wave/boundary-layer interaction (SWBLI) is formed over...
master thesis 2020
document
Sharma, Suryansh (author)
master thesis 2020
document
Liu Xu, Vanessa (author)
Electrification of aviation is driving new aircraft configurations consisting in slender, lighter wings with several propellers spread across the wing span, including the wing tips. Thinner wings with high aspect ratios tend to be more flexible, and thus, more susceptible to wing flutter, a dynamic aeroelastic instability characterised by...
master thesis 2020
document
Rietema, Roald (author)
Recent decades, an ongoing trend has emerged in the upscaling of wind turbines in order to compete with traditional energy resources. For conventional wind turbines, aside from improving safety, the driving factors for new designs have always been increased efficiency and performance. This has led to novel wind turbine designs comprising thin...
master thesis 2019
document
Tatomir, Niko (author)
Aeroelastic stability must be maintained for the entire flight duration. Of the vast phenomena that fall under the field of aeroelasticity, flutter is the most studied and influential in terms of driving aircraft design. As such, it is the main topic of analysis of this Master Thesis. For flutter analysis, it is of critical importance to...
master thesis 2019
document
Verdonck, Hendrik (author)
Aircraft manufacturers have to prove a flutter free design for all operational cases within the complete flight envelope plus a safety margin. This certification process relies on validated flutter computations which have to be made for all flight conditions including variations in the aircraft's loading and failure cases. The aerodynamic...
master thesis 2019
document
De Petter, Christophe (author)
Shock-Wave/Turbulent-Boundary Layer Interactions (SWTBLI) often occur in applications of technological interest. The associated inherent low-frequency unsteadiness dictates the use of Large-Eddy Simulation (LES) approaches to resolve the interaction, which unavoidably implies a very high computational cost. For this reason, no well-resolved long...
master thesis 2019
document
Sodja, J. (author), Roizner, Federico (author), De Breuker, R. (author), Karpel, M. (author)
The first experimental application of the Parametric Flutter Margin method for identification of aeroelastic instabilities is presented. The experiment was performed in two steps using a two degree-of-freedom wing model mounted in the wind tunnel. First, the reference flutter and divergence conditions were found by increasing the airstream...
conference paper 2017
document
Navalkar, S.T. (author)
Wind energy has reached a high degree ofmaturity: for wind-rich onshore locations, it is already competitive with conventional energy sources. However, for low-wind, remote and offshore regions, research efforts are still required to enhance its economic viability. While it is possible to reduce the cost of energy by upscaling wind turbines, it...
doctoral thesis 2016
document
Berthold, C.R. (author)
In this work a numerical method is developed to efficiently simulate limit cycle oscillations and forced response amplitudes of fluid-structure interaction (FSI) problems. The method computes a solution in the frequency-domain and can therefore only deal with periodic unsteadiness. As flow solver the Harmonic Balance method is used which is...
master thesis 2016
document
Lambers, A.C. (author)
Aircraft concepts with high aspect ratio wings have been investigated more extensively in the recent past, as such configurations would reduce the induced drag significantly. At the same time, the high aspect ratio challenges the wing’s aero-structural stability (flutter). Therefore there is a need to perform aero-structural analysis already...
master thesis 2016
document
Visser, M. (author)
Flutter-induced vibrations can easily cause large structures like airplanes and bridges to fail, which even today makes flutter prediction an important topic of research. To predict flutter, recursive system identification can be used to capture the time-varying behavior using time-invariant techniques combined with the forgetting of old data....
master thesis 2015
Searched for: subject%3A%22flutter%22
(1 - 20 of 27)

Pages

List view
Grid view