DOI: 10.1615/ICHMT.2009.TurbulHeatMassTransf
ISBN Print: 978-1-56700-262-1
ISSN: 2377-2816
Modeling separated flow transition with a transport intermittency model
RÉSUMÉ
In this study we propose a local-variable-based laminar-turbulence transition model that considers the effects of different instability modes existing in separated flows. This model is based on k-ω-γ three-equation eddy-viscosity concept with k representing the fluctuating kinetic energy, ω the specific dissipation rate and the intermittency factor γ. It takes into account not only the local effects that the freestream disturbances penetrate into the laminar boundary layer by convection and viscous diffusion, as described by the transport equations, but also the non-local effect that by pressure diffusion, as represented by an elliptic approach. Such attempt makes the present model responding to freestream turbulence intensity properly and predicting both the long and short bubble length well, which indicates that the mixed-mode transition scenario do benefit from such a modular prediction approach that mirrors the conceptual understanding of the transition process.