Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation
The purpose of this research is to conduct a preliminary investigation into the possibility of suppressing the flutter and post-flutter (chaotic) responses of a two-dimensional self-excited airfoil with a cubic nonlinear stiffness (in torsion) and linear viscous damping via closed-loop harmonic para...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-09-01
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| Series: | Fluids |
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| Online Access: | https://www.mdpi.com/2311-5521/5/4/165 |
| _version_ | 1797552361071181824 |
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| author | Robert Bruce Alstrom |
| author_facet | Robert Bruce Alstrom |
| author_sort | Robert Bruce Alstrom |
| collection | DOAJ |
| description | The purpose of this research is to conduct a preliminary investigation into the possibility of suppressing the flutter and post-flutter (chaotic) responses of a two-dimensional self-excited airfoil with a cubic nonlinear stiffness (in torsion) and linear viscous damping via closed-loop harmonic parametric excitation. It was found that the initial configuration of the proposed control scheme caused the torsional/pitch dynamics to act as a nonlinear energy sink; as a result, it was identified that the mechanisms of vibration suppression are the <i>resonance capture cascade</i> and the short duration or <i>isolated resonance capture</i>. It is the isolated resonance capture that is responsible for the second-order-like damping and full vibration suppression of the aeroelastic system. The unforced and closed-loop system was subjected to random excitation to simulate aerodynamic turbulence. It was found that the random excitation suppresses the phase-coherent chaotic response, and the closed-loop system is susceptible to random excitation. |
| first_indexed | 2024-03-10T15:59:56Z |
| format | Article |
| id | doaj.art-9290b659c0f14b1684a43e859f7e90e2 |
| institution | Directory Open Access Journal |
| issn | 2311-5521 |
| language | English |
| last_indexed | 2024-03-10T15:59:56Z |
| publishDate | 2020-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fluids |
| spelling | doaj.art-9290b659c0f14b1684a43e859f7e90e22023-11-20T15:22:20ZengMDPI AGFluids2311-55212020-09-015416510.3390/fluids5040165Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric ExcitationRobert Bruce Alstrom0Department of National Center for Physical Acoustics (10001011), University of Mississippi, University, MS 38677, USAThe purpose of this research is to conduct a preliminary investigation into the possibility of suppressing the flutter and post-flutter (chaotic) responses of a two-dimensional self-excited airfoil with a cubic nonlinear stiffness (in torsion) and linear viscous damping via closed-loop harmonic parametric excitation. It was found that the initial configuration of the proposed control scheme caused the torsional/pitch dynamics to act as a nonlinear energy sink; as a result, it was identified that the mechanisms of vibration suppression are the <i>resonance capture cascade</i> and the short duration or <i>isolated resonance capture</i>. It is the isolated resonance capture that is responsible for the second-order-like damping and full vibration suppression of the aeroelastic system. The unforced and closed-loop system was subjected to random excitation to simulate aerodynamic turbulence. It was found that the random excitation suppresses the phase-coherent chaotic response, and the closed-loop system is susceptible to random excitation.https://www.mdpi.com/2311-5521/5/4/165closed-loop harmonic parametric excitationcontinuous-time flutter controltime–frequency analysiswavelet spectratransient physicscontrol-induced nonlinear energy sink |
| spellingShingle | Robert Bruce Alstrom Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation Fluids closed-loop harmonic parametric excitation continuous-time flutter control time–frequency analysis wavelet spectra transient physics control-induced nonlinear energy sink |
| title | Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation |
| title_full | Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation |
| title_fullStr | Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation |
| title_full_unstemmed | Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation |
| title_short | Controlling the Chaotic Motions of an Airfoil with a Nonlinear Stiffness Using Closed-Loop Harmonic Parametric Excitation |
| title_sort | controlling the chaotic motions of an airfoil with a nonlinear stiffness using closed loop harmonic parametric excitation |
| topic | closed-loop harmonic parametric excitation continuous-time flutter control time–frequency analysis wavelet spectra transient physics control-induced nonlinear energy sink |
| url | https://www.mdpi.com/2311-5521/5/4/165 |
| work_keys_str_mv | AT robertbrucealstrom controllingthechaoticmotionsofanairfoilwithanonlinearstiffnessusingclosedloopharmonicparametricexcitation |