Lab Home | Phone | Search
Center for Nonlinear Studies  Center for Nonlinear Studies
 Home 
 People 
 Current 
 Affiliates 
 Visitors 
 Students 
 Research 
 ICAM-LANL 
 Publications 
 Conferences 
 Workshops 
 Sponsorship 
 Talks 
 Colloquia 
 Colloquia Archive 
 Seminars 
 Postdoc Seminars Archive 
 Quantum Lunch 
 Quantum Lunch Archive 
 CMS Colloquia 
 Q-Mat Seminars 
 Q-Mat Seminars Archive 
 P/T Colloquia 
 Archive 
 Kac Lectures 
 Kac Fellows 
 Dist. Quant. Lecture 
 Ulam Scholar 
 Colloquia 
 
 Jobs 
 Postdocs 
 CNLS Fellowship Application 
 Students 
 Student Program 
 Visitors 
 Description 
 Past Visitors 
 Services 
 General 
 
 History of CNLS 
 
 Maps, Directions 
 CNLS Office 
 T-Division 
 LANL 
 
Thursday, May 18, 2017
10:00 AM - 11:00 AM
T-4 Conference Room (TA-3, Bldg 0524)

Seminar

Large-Eddy Simulations of Wall Bounded Turbulent Flows

Ravi Samtaney
Kaust University

We report recent progress on wall-resolved and wall-modeled large-eddy simulation (LES) of wall-bounded turbulent flows, including model development and applications. The sub-grid-scale (SGS) model employed is the stretched spiral vortex SGS model, originally proposed by Misra & Pullin (Phys. Fluids 1997). The present wall-model is an extension of the original one proposed by Pullin & co-workers in a series of papers on LES of high Reynolds number flows in a channel, turbulent boundary layer, and a pipe. Our extension to the wall model includes three modifications: relaxation of the log-law assumption, extension into two-dimensional wall model and reformulation in generalized curvilinear coordinates. Five flow configurations are examined in detail. The first case is that of a zero pressure gradient turbulent boundary layer in which our objective is to address whether the mean velocity profile obeys a log-law or a power-law. The second case is that of a separated and re-attached turbulent boundary layer; where the two-dimensional wall model is shown to reasonably predict the wall stress in the separated flow. The third case is flow over period hill, a benchmark case for LES modeling, and our LES show good results compared with experiments. The fourth and perhaps more challenging case is that of a flow over a circular cylinder with emphasis on reproduction of the drag crisis at Re~O(105) and quantification of skin friction on the surface. The final case is that of flows over airfoils, which is a prerequisite step for applying the present curvilinear wall model on cases with even more complex geometry. In all these, our emphasis is on validation and quantitative comparisons with experimental data when available.

Host: Balu Nadiga