Numerical investigation of confined turbulent shear flows
Abstract
A derivation of the method of coarse graining for the computation of turbulent flows, one which strengthens and clarifies its theoretical foundation is presented. By the application of the method to the study of the turbulent flow in a channel and behind a piston in compressive motion it was shown that a promising start was made toward acquiring the ability to predict the mean properties of turbulent flows. The principal improvement in the method of coarse graining consists of the establishment of a general law of turbulent diffusion which applies to any scalar that is passively convected in a turbulent flow. The law is in the form of an expansion in roughly the Lagrangian integral time scale. The transport law is used to derive a closed set of equations for the mean vorticity and mean squared fluctuating vorticity. Other innovations include a more precise accounting of the effects of the local turbulence on the velocity moments and the use of an explicit equation for mean squared fluctuating vorticity instead of mean squared vorticity.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- December 1976
- Bibcode:
- 1976PhDT.......103B
- Keywords:
-
- Numerical Analysis;
- Prediction Analysis Techniques;
- Shear Flow;
- Turbulent Flow;
- Equations Of Motion;
- Euler-Lagrange Equation;
- Transport Properties;
- Vorticity Transport Hypothesis;
- Fluid Mechanics and Heat Transfer