High-Resolution Modeling of Multiscale Transient Phenomena in Turbulent Boundary Layers

Abstract

High delity n umerical simulation of wall-bounded turbulence requires physically sound representation of the small scale unsteady processes governing near-wall momentum, heat, and mass transfer. Conventional wall treatments do not capture the diverse multiphysics ow regimes relevant to engineering applications.To obtain a robust yet computationally a ordable near-wall submodel for turbulent o w computations, the ne-grained spatial structure and time evolution of the near-wall ow is simulated using a model formulated on a 1D domain corresponding to the wall-normal direction. This approach captures the strong variation of ow properties in the wall-normal direction and the transient i n teractions between this highly inhomogeneous region and the more nearly homogeneous (at ne scales) ow farther from the wall.The 1D simulation utilizes the One Dimensional Turbulence (ODT) methodology, whose formulation for the present application is described in detail. Demonstrations of ODT performance with regard to aspects of ow p h ysics relevant to near-wall ow modeling are presented.The coupling of ODT to a large eddy simulation (LES) of con ned turbulent o w i s d escribed, and the performance of the coupled formulation is demonstrated. It is concluded that this formulation has the potential to provide the delity needed for engineering applications at an a ordable computational cost.

One-dimensional turbulence: vector formulation and application to free shear flows

“…A practical feature of the vector formulation of ODT is that it may facilitate the use of the model as a subgrid momentum closure for large-eddy simulation (LES) of turbulence. An effort to implement ODT as a near-wall submodel for LES has been initiated (Kerstein et al 2001).…”

“…In the flows considered here, the dominant pressure-velocity interactions are inviscid at high Reynolds number (Re), simplifying the interpretation of results. Nevertheless, viscous effects are fully represented within the model, so the formulation introduced here is directly applicable to boundary layers and other flows (Kerstein et al 2001).…”

“…Thus, the focus of model comparisons to DNS is the model representation of inviscid energy transfer, which is the novel feature of the present formulation. Application of the vector velocity formulation to turbulent boundary layers, in which viscous processes play a key role, is reported elsewhere (Kerstein et al 2001).…”