dc.contributor |
Universitat Politècnica de Catalunya. Departament de Màquines i Motors Tèrmics |
dc.contributor |
Universitat Politècnica de Catalunya. CTTC - Centre Tecnològic de la Transferència de Calor |
dc.contributor.author |
Trias Miquel, Francesc Xavier |
dc.contributor.author |
Folch, David |
dc.contributor.author |
Gorobets, Andrei |
dc.contributor.author |
Oliva Llena, Asensio |
dc.date |
2015-06-23 |
dc.identifier.citation |
Trias, F. X., Folch, D., Gorobets, A., Oliva, A. Building proper invariants for eddy-viscosity subgrid-scale models. "Physics of fluids", 23 Juny 2015, vol. 27, núm. 6, p. 065103-1-065103-17. |
dc.identifier.citation |
1070-6631 |
dc.identifier.citation |
10.1063/1.4921817 |
dc.identifier.uri |
http://hdl.handle.net/2117/85302 |
dc.language.iso |
eng |
dc.relation |
http://scitation.aip.org/content/aip/journal/pof2/27/6/10.1063/1.4921817 |
dc.rights |
info:eu-repo/semantics/openAccess |
dc.subject |
Àrees temàtiques de la UPC::Enginyeria mecànica::Mecànica de fluids |
dc.subject |
Fluid mechanics |
dc.subject |
Turbulence |
dc.subject |
phase space methods |
dc.subject |
tensor methods |
dc.subject |
inequalities |
dc.subject |
large eddy simulations |
dc.subject |
isotropic turbulence |
dc.subject |
Mecànica de fluids |
dc.subject |
Turbulència |
dc.title |
Building proper invariants for eddy-viscosity subgrid-scale models |
dc.type |
info:eu-repo/semantics/publishedVersion |
dc.type |
info:eu-repo/semantics/article |
dc.description.abstract |
Copyright 2015 AIP Publishing. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. |
dc.description.abstract |
Direct simulations of the incompressible Navier-Stokes equations are limited to relatively low-Reynolds numbers. Hence, dynamically less complex mathematical formulations are necessary for coarse-grain simulations. Eddy-viscosity models for large-eddy simulation is probably the most popular example thereof: they rely on differential operators that should properly detect different flow configurations (laminar and 2D flows, near-wall behavior, transitional regime, etc.). Most of them are based on the combination of invariants of a symmetric tensor that depends on the gradient of the resolved velocity field, . In this work, models are presented within a framework consisting of a 5D phase space of invariants. In this way, new models can be constructed by imposing appropriate restrictions in this space. For instance, considering the three invariants P GG T , Q GG T , and R GG T of the tensorGG T , and imposing the proper cubic near-wall behavior, i.e., , we deduce that the eddy-viscosity is given by . Moreover, only R GG T -dependent models, i.e., p > - 5/2, switch off for 2D flows. Finally, the model constant may be related with the Vreman’s model constant via ; this guarantees both numerical stability and that the models have less or equal dissipation than Vreman’s model, i.e., . The performance of the proposed models is successfully tested for decaying isotropic turbulence and a turbulent channel flow. The former test-case has revealed that the model constant, C s3pqr , should be higher than 0.458 to obtain the right amount of subgrid-scale dissipation, i.e., C s3pq = 0.572 (p = - 5/2), C s3pr = 0.709 (p = - 1), and C s3qr = 0.762 (p = 0). |
dc.description.abstract |
Peer Reviewed |