Abo Bibliothek: Guest
THMT-15. Proceedings of the Eighth International Symposium On Turbulence Heat and Mass Transfer
September, 15-18, 2015, Sarajevo, Bosnia and Herzegovina

DOI: 10.1615/ICHMT.2015.THMT-15


ISBN Print: 978-1-56700-427-4

ISBN CD: 978-1-56700-428-8

Characteristics of the near wake region behind a cylinder at critical and super-critical Reynolds numbers

pages 331-334
DOI: 10.1615/ICHMT.2015.THMT-15.630
Get accessGet access

ABSTRAKT

Large-eddy simulations (LES) of the flow past a circular cylinder are used to investigate the characteristics of the near wake region at Reynolds numbers Re = 2.5 × 105 − 8.5 × 105. This range encompasses both the critical and super-critical regimes. Wake characteristic lengths are measured and compared between the different Reynolds numbers. It is shown that the super-critical regime is characterised by a plateau in the drag coefficient at about CD ~ 0.22, and a quasi-stable wake which has a width of dω/D ~ 0.4. Power spectra of the lift fluctuations are computed. Wake vortex shedding is found to occur for both regimes investigated, although a jump in frequencies is observed when the flow enters the super-critical regime. The analysis also shows a steep decrease in the fluctuating lift when entering the super-critical regime. Furthermore, the analysis of the turbulent statistics shows that after the changes occurring at critical Reynolds numbers, the wake enters a regime where its dynamics is quite similar regardless of the Reynolds number.

Digitales Portal Digitale Bibliothek eBooks Zeitschriften Referenzen und Berichte Forschungssammlungen Preise und Aborichtlinien Begell House Kontakt Language English 中文 Русский Português German French Spain