Název: Annular impinging jets and an active control of hysteretic effects
Autoři: Devani, Yogendrasasidhar ; Antošová, Zuzana ; Trávníček, Zdeněk
Typ dokumentu: Výzkumné zprávy
Rok: 2022
Jazyk: eng
Abstrakt: An annular air jet with and without flow control was studied experimentally using flow visualization and measurements of the wall pressure and flow velocity by the Pitot and Prandtl probes and the hot-wire anemometer. To investigate flow control swirling effects, eight synthetic jets were generated from the annular nozzle center body.The experiments cover Reynolds numbers 4000–10000 (evaluated from the outer exit diameter of the annular nozzle). For Re<9000, the bistability and hysteresis were identified and two different flow field patterns (A and B) were found under the same boundary conditions. For A pattern, a small recirculation area (bubble) of separated flow is attached to the nozzle center body. For B pattern, a large recirculation area of separated flow bridges entire nozzle-to-wall distance. For higher Re > 9000, the bistability and hysteresis were not found.Flow control swirling effects causes suppression of the hysteresis. Moreover, weak flow control causes that the entire annular jet is forced into a precessing motion.
Klíčová slova: annular jet; bistability; hysteresis; impinging jet
Číslo projektu: GC21-26232J (CEP)
Poskytovatel projektu: GA ČR

Instituce: Ústav termomechaniky AV ČR (web)
Informace o dostupnosti dokumentu: Dokument je dostupný v příslušném ústavu Akademie věd ČR.
Původní záznam: https://hdl.handle.net/11104/0336270

Trvalý odkaz NUŠL: http://www.nusl.cz/ntk/nusl-511836


Záznam je zařazen do těchto sbírek:
Věda a výzkum > AV ČR > Ústav termomechaniky
Zprávy > Výzkumné zprávy