The dynamics of coherent structures in the wall region of a turbulent boundary layer
Abstract
Expanding the instantaneous field in the empirical eigenfunctions, the proper orthogonal decomposition theorem of Lumley (1967, 1981) is used to model the wall region of a turbulent boundary layer. Galerkin projection is employed to truncate the representation in order to obtain low-dimensional sets of ordinary differential equations from the Navier-Stokes equations. Model equations representing the dynamical behavior of Herzog (1986) eigenfunctions in the form of streamwise rolls are shown to exhibit intermittency. It is suggested that previously observed bursting events associated with streamwise vortex pairs are triggered by the pressure signal from the outer part of the boundary layer. The results provide a link between low-dimensional chaotic dynamics and a realistic turbulent open flow system.
- Publication:
-
Journal of Fluid Mechanics
- Pub Date:
- July 1988
- DOI:
- 10.1017/S0022112088001818
- Bibcode:
- 1988JFM...192..115A
- Keywords:
-
- Computational Fluid Dynamics;
- Rayleigh Number;
- Turbulent Boundary Layer;
- Turbulent Flow;
- Wall Flow;
- Chaos;
- Coherence;
- Dynamical Systems;
- Galerkin Method;
- Navier-Stokes Equation;
- Shear Flow;
- Fluid Mechanics and Heat Transfer