ODT subgrid closure for LES: application to decaying isotropic turbulence

Randall McDermott, University of Utah

In large eddy simulation (LES) of turbulent flows the flow field of interest must be spatially filtered so that it can be accurately represented by the limited degrees of freedom available on digital computers. Coarse spatial resolution truncates the length scales responsible for important physical phenomena. Hence, a model for the unresolved (subgrid) scales is required if the filtered field is to evolve properly. In this poster a new method to close the LES equations using the one-dimensional turbulence model (ODT) is presented. ODT can be thought of as a one-dimensional surrogate for a direct numerical simulation, hence detailed spatial and temporal structure can be captured in the simulation. The results are compared to the 1971 data of Comte-Bellot and Corrsin, and the recently published high Reynolds number update to this data set by Kang et al. (JFM 480, 2003).

Abstract Author(s): R. McDermott, R. Schmidt, A. Kerstein and P. Smith