Analysis of errors occurring in large eddy simulation.
Philos Trans A Math Phys Eng Sci
; 367(1899): 2873-83, 2009 Jul 28.
Article
in En
| MEDLINE
| ID: mdl-19531509
ABSTRACT
We analyse the effect of second- and fourth-order accurate central finite-volume discretizations on the outcome of large eddy simulations of homogeneous, isotropic, decaying turbulence at an initial Taylor-Reynolds number Re(lambda)=100. We determine the implicit filter that is induced by the spatial discretization and show that a higher order discretization also induces a higher order filter, i.e. a low-pass filter that keeps a wider range of flow scales virtually unchanged. The effectiveness of the implicit filtering is correlated with the optimal refinement strategy as observed in an error-landscape analysis based on Smagorinsky's subfilter model. As a point of reference, a finite-volume method that is second-order accurate for both the convective and the viscous fluxes in the Navier-Stokes equations is used. We observe that changing to a fourth-order accurate convective discretization leads to a higher value of the Smagorinsky coefficient C(S) required to achieve minimal total error at given resolution. Conversely, changing only the viscous flux discretization to fourth-order accuracy implies that optimal simulation results are obtained at lower values of C(S). Finally, a fully fourth-order discretization yields an optimal C(S) that is slightly lower than the reference fully second-order method.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Philos Trans A Math Phys Eng Sci
Journal subject:
BIOFISICA
/
ENGENHARIA BIOMEDICA
Year:
2009
Document type:
Article
Affiliation country:
Netherlands