Large-eddy simulation of turbulent wavy boundary flow - Illustration of vortex dynamics
Journal
Journal of Turbulence
Journal Volume
5
Date Issued
2004
Author(s)
Abstract
Large-eddy simulation (LES) is used to investigate three-dimensional turbulent flow over a wavy boundary. An efficient immersed boundary method (IBM) for simulating turbulent flows in complex geometries is presented. The method is based on a finite-volume approach on a non-staggered Cartesian mesh and a fractional-step method. A force is applied on the body surface through an immersed ghost-cell method. Both steady and unsteady flows are simulated. A steady flow simulation provides not only the mean and turbulence statistics but also visualization of the Görtler vortices. The simulation shows that Görtler vortices are formed by a sequential vortex reconnection process and broken down due to vortex separation. The unsteady oscillatory flow displays the three-dimensional vortex formation/transport cycle which is shown to be important for sediment transport. The turbulent structure is fully three-dimensional and is clearly seen from the current animations. ©2004 IOP Publishing Ltd.
Type
journal article