Assessment of the shear-improved Smagorinsky model in laminar-turbulent transitional channel flow

Abstract

In this paper, the shear-improved Smagorinsky model (SISM) is assessed in a K-type transitional channel flow. Our numerical simulation results show that the original SISM model is still too dissipative to predict the transitional channel flow. Two former reported empirical correction approaches, including a low-Reynolds-number correction and a shape-factor-based intermittency correction, are applied to further promote the capability of the SISM model in simulating the transition process. Numerical tests show that the shape-factor-based intermittency correction approach can correctly improve the transition-prediction capability of the SISM model, while the low-Reynolds-number correction approach fails. Furthermore, the shape-factor-based intermittency-corrected SISM model can capture the vortical structures during the transitional process very well and possesses the grid-insensitive characteristics.

Keywords:

• shear-improved Smagorinsky model
• transitional channel flow

Acknowledgements

Numerical simulations were finished at the Dawn cluster in Peking University, China. We acknowledge the financial support provided by National Natural Science Foundation of China (Grants Nos. 91130001, 11221061, and 11302006). Author Z. Xia wants to thank the support from National Science Foundation for Postdoctoral Scientists of China (Grant No. 2012M520109).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

National Natural Science Foundation of China [grants number 91130001], [grant number 11221061], [grant number 11302006]; National Science Foundation for Postdoctoral Scientists of China [grant number 2012M520109].