Development of a Two-Scale Turbulence Model and its Applications
Abstract
Using second order closure turbulence model to predict turbulent flows is known to be more successful than the classical mixing length model. To improve the predictability of the second order closure model, work proposes to consider two turbulent scales in the modelling turbulent flows. One scale is based on using the turbulent kinetic energy, k, and its dissipation rate, e, to characterize the large energy containing eddies. The other scale is based on the dissipation rate and the kinematic viscosity, v, to characterize the small energy dissipating eddies. The second scale is based on the well known Kolmogorov hypothesis that dissipation of turbulent kinetic energy occurs primarily at small eddies. The turbulence model derived based on the concept of two different scales is called the two scale turbulence model. The existing turbulence model, which is modelled based on the one scale concept of k and e, is called the one scale turbulence model. The two-scale turbulence model is then applied to predict turbulent free shear flows and recirculating flows. The calculations were done in 3 parts. The first test case was nonbuoyant free shear flows which included round and plane jets in stagnant and moving streams, plane and round buoyant jets having different Froude numbers. Finally, some results were obtained for recirculating flows.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1986
- Accession Number
- ADA174449
Entities
People
- Ching-Jen Chen
- Kanwerdip Singh
Organizations
- University of Iowa