Analysis of Two-Equation Turbulence Models for Recirculating Flows.
Abstract
The two-equation K-epsilon model is used to analyze turbulent separated flow past a backward-facing step. It is shown that if the model constants are modified to be consistent with the accepted energy decay rate for isotropic turbulence, the dominant features of the flow field -- namely -- the size of the separation bubble and the streamwise component of the mean velocity, can be accurately predicted. In addition, except in the vicinity of the step, very good predictions for the turbulent shear stress, the wall pressure and the wall shear stress are obtained. The model is also shown to provide good predictions for the turbulence intensity in the region downstream of the reattachment point. Estimated long-time growth rates for the turbulent kinetic energy and dissipation rate of homogeneous shear flow are utilized to develop an optimal set of constants for the two equation K-epsilon model. The physical implications of the model performance are also discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1991
- Accession Number
- ADA240683
Entities
People
- S. Thangam