This paper deals with the numerical simulation of the unsteady flow field around a 1:5 rectangular cylinder at zero flow incidence, low Mach number and high Reynolds number. The three-dimensional Detached-Eddy Simulation technique associated with the one-equation turbulence model of Spalart and Allmaras (SA-DES) is employed. This is a hybrid method which combines the RANS approach near the walls and the LES approach away from the walls. It is particularly useful in case high-Reynolds-number turbulent boundary layers have to be computed. 2-D and 3-D unsteady RANS simulations using the Spalart-Allmaras (SAE) and an Explicit Algebraic Reynolds Stress Model (LEA k - ω) are also proposed. Comparison with experiments shows that, while the URANS-SAE equations are not able to capture the unsteadiness of the flow, the 2-D URANS-LEA computation gives reasonable results, although the frequency of vortex shedding is slightly underestimated and the lift mean fluctuation is overestimated. No improvement is obtained by applying the URANS-LEA approach on the much more expensive 3-D mesh, since nearly two-dimensional flow field is obtained. In contrast, the accuracy of the result can be enhanced by performing a 3-D SA-DES simulation, which allows to resolve much finer and three-dimensional vortical structures. The conclusions of this work confirm the interest for this hybrid non-zonal technique and encourage to apply it for even more challenging test case.

Detached-Eddy Simulation of flow around a 1:5 rectangular cylinder / Claudio Mannini; Ante Soda; Günter Schewe; Keith Weinman. - (2008), pp. 1-16. (Intervento presentato al convegno 6th International Colloquium on Bluff Body Aerodynamics and Applications (BBAA 6) tenutosi a Milano nel 20-24 luglio 2008).

Detached-Eddy Simulation of flow around a 1:5 rectangular cylinder

MANNINI, CLAUDIO;
2008

Abstract

This paper deals with the numerical simulation of the unsteady flow field around a 1:5 rectangular cylinder at zero flow incidence, low Mach number and high Reynolds number. The three-dimensional Detached-Eddy Simulation technique associated with the one-equation turbulence model of Spalart and Allmaras (SA-DES) is employed. This is a hybrid method which combines the RANS approach near the walls and the LES approach away from the walls. It is particularly useful in case high-Reynolds-number turbulent boundary layers have to be computed. 2-D and 3-D unsteady RANS simulations using the Spalart-Allmaras (SAE) and an Explicit Algebraic Reynolds Stress Model (LEA k - ω) are also proposed. Comparison with experiments shows that, while the URANS-SAE equations are not able to capture the unsteadiness of the flow, the 2-D URANS-LEA computation gives reasonable results, although the frequency of vortex shedding is slightly underestimated and the lift mean fluctuation is overestimated. No improvement is obtained by applying the URANS-LEA approach on the much more expensive 3-D mesh, since nearly two-dimensional flow field is obtained. In contrast, the accuracy of the result can be enhanced by performing a 3-D SA-DES simulation, which allows to resolve much finer and three-dimensional vortical structures. The conclusions of this work confirm the interest for this hybrid non-zonal technique and encourage to apply it for even more challenging test case.
2008
Proceedings of 6th International Colloquium on Bluff Body Aerodynamics and Applications
6th International Colloquium on Bluff Body Aerodynamics and Applications (BBAA 6)
Milano
20-24 luglio 2008
Claudio Mannini; Ante Soda; Günter Schewe; Keith Weinman
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/820825
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact