Stochastic self-energy subgrid model for the large eddy simulation of turbulent channel flows

1st Multiflow Summer Workshop

Kitsios, V.^1,2 ; Sillero, J.A.^3 ; Soria, J.^1,4 ; Frederiksen, J.S.^2

Laboratory for Turbulence Research in Aerospace and Combustion, Department of Mechanical and Aerospace Engineering, Monash University, Clayton 3800, Australia^1

Centre for Australian Weather and Climate Research, CSIRO Marine and Atmospheric Research, 107-121 Station St, Aspendale 3195, Australia^2

School of Aeronautics, Universidad Politécnica de Madrid, Pza. Cardenal Cisneros 3, E-28040 Madrid, Spain^3

Department of Aeronautical Engineering, King Abdulaziz University, Jeddah, Saudi Arabia^4

关键词: Friction velocity;    Kinetic energy spectra;    Mean-field shifts;    Model coefficient;    Physical interpretation;    Subgrid model;    Turbulent channel flows;    Wall bounded flows;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/506/1/012001/pdf
DOI  :  10.1088/1742-6596/506/1/012001

来源: IOP

【 摘 要 】

This paper presents the large eddy simulation (LES) of turbulent channel flow using a self-energy (SE) subgrid model with coefficients determined from reference direct numerical simulations (DNSs). In contrast to standard approaches that develop subgrid models based upon physical hypotheses, in the present SE approach the model coefficients are determined from the subgrid statistics of a DNS, with physical interpretations made apostiori. This technique is applied here for the first time to wall-bounded flows, specifically channel flow. The stochastic SE subgrid model consists of a meanfield shift, deterministic drain dissipation acting on the resolved field and a stochastic backscatter force. The deterministic SE subgrid model comprises of a net dissipation representing the net effect of the drain and backscatter. We present LESs that reproduce the time-averaged kinetic energy spectra of the DNS within the resolved scales. The direction and magnitude of the energy transfers in scale space can then be determined from the coefficients of the SE subgrid model. Results are presented for friction velocity based Reynolds numbers up to Reτ 950.