Název: Aeroelastic instability of differently porous U-profiles in crosswind direction
Autoři: Hračov, Stanislav ; Macháček, Michael
Typ dokumentu: Příspěvky z konference
Konference/Akce: International Conference Engineering mechanics 2022, Milovy (CZ), 20220509
Rok: 2022
Jazyk: eng
Abstrakt: Flow-induced vibrations of the flexibly mounted slender U-shaped beams allowed to oscillate in the crosswind direction only are studied experimentally in the wind tunnel. All beams are characterized by a cross section having a side ratio of along-wind to across-wind dimension equal to two. The effects of two depths of U profiles and two porosities of their flanges ( 0 % and 75 %) onto a loss of aeroelastic stability are investigated under the smooth flow conditions and for low Scruton numbers. The results indicate almost similar proneness of the non-porous beams to galloping-type oscillations to a rectangular prism with the same side ratio regardless their depth. The onset of across-wind galloping occurred in these cases at wind velocity very close to von-Kármán-vortex-resonance flow speed, even though the critical velocity predicted by the quasisteady theory is much lower. For porous and shallower U profile this asynchronous quenching also takes\nplace. However, the higher flange porosity reduces significantly not only the vortex-shedding effect, but also causes an increase in the onset galloping velocity above the critical speed determined for non-porous profiles. In the case of deeper U-shaped beam, the effect of higher porosity even suppresses the proneness to galloping
Klíčová slova: aeroelastic instability; asynchronous quenching; galloping; U profile; vortex shedding
Číslo projektu: GA19-21817S (CEP)
Poskytovatel projektu: GA ČR
Zdrojový dokument: Engineering mechanics 2022. Book of full texts, ISBN 978-80-86246-48-2, ISSN 1805-8248
Poznámka: Související webová stránka: https://www.engmech.cz/im/proceedings/show_p/2022/153

Instituce: Ústav teoretické a aplikované mechaniky AV ČR (web)
Informace o dostupnosti dokumentu: Dokument je dostupný v repozitáři Akademie věd.
Původní záznam: http://hdl.handle.net/11104/0331332

Trvalý odkaz NUŠL: http://www.nusl.cz/ntk/nusl-508574


Záznam je zařazen do těchto sbírek:
Věda a výzkum > AV ČR > Ústav teoretické a aplikované mechaniky
Konferenční materiály > Příspěvky z konference