Spectral transport model for turbulence
Abstract
The spectrum of inhomogeneous turbulence is modeled by an approach that is not limited to regimes of large Reynolds numbers or small mean-flow strain rates. In its simplest form and applied to incompressible flow, the model depends on five phenomenological constants defining the strength of turbulence coupling to mean flow, turbulence transport in physical and wave-number space, and mixing of stress-tensor components. The implications for homogeneous turbulence are investigated in detail and found to correspond well to the conclusions from more fundamental theories. Under appropriate limiting conditions, a turbulent system described by the model will relax over time into a state of approximate spectral equilibrium, permitting a reduction to a one-point model for the system that is substantially like the familiar K--(epsilon) model. This yields estimates of the present model's parameters and points to the way to improve modeling of flows beyond the applicability of the K--(epsilon) method.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- July 1990
- Bibcode:
- 1990STIN...9025295B
- Keywords:
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- Fluid Dynamics;
- Incompressible Flow;
- Spectral Theory;
- Transport Properties;
- Turbulence;
- Mathematical Models;
- Reynolds Number;
- Stresses;
- Fluid Mechanics and Heat Transfer