Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil
The present paper investigates the effects of noisy flow fluctuations on the fluid-structure interaction (FSI) behaviour of a span-wise flexible wing modelled as a two degree-of-freedom elastically mounted flapping airfoil. In the sterile flow conditions, the system undergoes a Hopf bifurcation as t...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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EDP Sciences
2018-01-01
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| Series: | MATEC Web of Conferences |
| Online Access: | https://doi.org/10.1051/matecconf/201814808001 |
| _version_ | 1818616266050502656 |
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| author | Bose Chandan Sarkar Sunetra Gupta Sayan |
| author_facet | Bose Chandan Sarkar Sunetra Gupta Sayan |
| author_sort | Bose Chandan |
| collection | DOAJ |
| description | The present paper investigates the effects of noisy flow fluctuations on the fluid-structure interaction (FSI) behaviour of a span-wise flexible wing modelled as a two degree-of-freedom elastically mounted flapping airfoil. In the sterile flow conditions, the system undergoes a Hopf bifurcation as the free-stream velocity exceeds a critical limit resulting in a stable limit-cycle oscillation (LCO) from a fixed point response. On the other hand, the qualitative dynamics changes from a stochastic fixed point to a random LCO through an intermittent state in the presence of irregular flow fluctuations. The probability density function depicts the most probable system state in the phase space. A phenomenological bifurcation (P-bifurcation) analysis based on the transition in the topology associated with the structure of the joint probability density function (pdf) of the response variables has been carried out. The joint pdf corresponding to the stochastic fixed point possesses a Dirac delta function like structure with a sharp single peak around zero. As the mean flow speed crosses the critical value, the joint pdf bifurcates to a crater-like structure indicating the occurrence of a P-bifurcation. The intermittent state is characterized by the co-existence of the unimodal as well as the crater like structure. |
| first_indexed | 2024-12-16T16:47:04Z |
| format | Article |
| id | doaj.art-a728486b32484bc19831ee22448506a6 |
| institution | Directory Open Access Journal |
| issn | 2261-236X |
| language | English |
| last_indexed | 2024-12-16T16:47:04Z |
| publishDate | 2018-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | MATEC Web of Conferences |
| spelling | doaj.art-a728486b32484bc19831ee22448506a62022-12-21T22:24:09ZengEDP SciencesMATEC Web of Conferences2261-236X2018-01-011480800110.1051/matecconf/201814808001matecconf_icoev2018_08001Stochastic Bifurcation Analysis of an Elastically Mounted Flapping AirfoilBose ChandanSarkar SunetraGupta SayanThe present paper investigates the effects of noisy flow fluctuations on the fluid-structure interaction (FSI) behaviour of a span-wise flexible wing modelled as a two degree-of-freedom elastically mounted flapping airfoil. In the sterile flow conditions, the system undergoes a Hopf bifurcation as the free-stream velocity exceeds a critical limit resulting in a stable limit-cycle oscillation (LCO) from a fixed point response. On the other hand, the qualitative dynamics changes from a stochastic fixed point to a random LCO through an intermittent state in the presence of irregular flow fluctuations. The probability density function depicts the most probable system state in the phase space. A phenomenological bifurcation (P-bifurcation) analysis based on the transition in the topology associated with the structure of the joint probability density function (pdf) of the response variables has been carried out. The joint pdf corresponding to the stochastic fixed point possesses a Dirac delta function like structure with a sharp single peak around zero. As the mean flow speed crosses the critical value, the joint pdf bifurcates to a crater-like structure indicating the occurrence of a P-bifurcation. The intermittent state is characterized by the co-existence of the unimodal as well as the crater like structure.https://doi.org/10.1051/matecconf/201814808001 |
| spellingShingle | Bose Chandan Sarkar Sunetra Gupta Sayan Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil MATEC Web of Conferences |
| title | Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil |
| title_full | Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil |
| title_fullStr | Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil |
| title_full_unstemmed | Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil |
| title_short | Stochastic Bifurcation Analysis of an Elastically Mounted Flapping Airfoil |
| title_sort | stochastic bifurcation analysis of an elastically mounted flapping airfoil |
| url | https://doi.org/10.1051/matecconf/201814808001 |
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