Development of a k–ω–ϕ–α turbulence model based on elliptic blending and applications for near-wall and separated flows

ABSTRACT

A new turbulence model based on elliptic blending, termed as k − ω − ϕ − α model, is developed. This model uses the latest version of Wilcox's k − ω model in near-wall region and changes gradually to the model elsewhere. The capabilities of the present model are evaluated on near-wall and separation flows, i.e. the 2D fully developed channel flow, the asymmetric plane diffuser flow and the 2D backward-facing step flow, in comparison with available direct numerical simulation (DNS) and experimental data. The computational results are compared also to those from the popular model and the original model, and the present model is more stable than the model in complex flows. The present model provides indistinguishable velocity profiles and improved turbulent kinetic energy profiles compared to the model in the channel flow, while in the separation flows tested herein, the present model can obtain comparable results with the model, and both of them show improvements to some extent compared with the model.

KEYWORDS:

• Turbulence model
• k–ω–ϕ–α model
• elliptic blending
• near-wall flow
• separated flow

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 11102117] and The Hong Kong Polytechnic University [grant number G-YL41].