A critical Reynolds number hypothesis and its relation to phenomenological turbulence models
Abstract
Assumptions about the basic nature of the turbulent mixing process in turbulence models are suggested to be interpreted as implying that turbulent flows tend toward a dynamic equilibrium characterized by a Reynolds number based on the effective viscosity of the flow. The validity of this hypothesis referred to as the critical Reynolds number hypothesis is discussed, and its relation to turbulence prediction methods is assessed by considering the predictions of a number of turbulence models for a range of free shear flows. It is shown that the critical Reynolds number hypothesis leads to a natural classification for turbulence models and that this classification is consistent with the performances of the models. There is little disagreement that the more complex turbulence models have reasonable generality. The two equation models which use differential equations for turbulence velocity and length scales can be regarded as a subset of the more complex Reynolds stress models.
 Publication:

25th Heat Transfer and Fluid Mechanics Institute
 Pub Date:
 1976
 Bibcode:
 1976htfm.proc..152B
 Keywords:

 Critical Velocity;
 Dynamic Models;
 Prediction Analysis Techniques;
 Reynolds Number;
 Turbulence Models;
 Turbulent Flow;
 Flow Velocity;
 Fluid Dynamics;
 Free Flow;
 Mathematical Models;
 Shear Flow;
 Turbulent Mixing;
 Fluid Mechanics and Heat Transfer