Subgrid scale structure of turbulence subject to surface wave straining

ORAL

Abstract

The subgrid-scale (SGS) stresses and energy fluxes of a turbulent flow underneath a surface wave are investigated with direct numerical simulation. The SGS stresses is decomposed into three parts: the wave induced stress, the cross-interaction stress and the turbulent SGS stress. The turbulent SGS stress and other purely turbulence-related statistics are found to be weakly dependent on the wave shape range. Decomposition of the energy flux shows that an eddy-viscosity model is suitable for the turbulent SGS stress but is incapable of modeling the wave induced stress due to its different wavenumber with the wave induced straining. The budget equations for the filtered kinetic energy and the SGS kinetic energy are subdivided through the velocity partition, showing that direct energy transfer between scales only occurs within the same type of motion (wave induced motion or turbulence). The transport terms play an important role in the budget equation for the turbulent SGS kinetic energy.

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Presenters

  • Kuanyu Chen

    State Key Laboratory for Turbulence and Complex Systems and Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing, 100871, P. R. China

Authors

  • Kuanyu Chen

    State Key Laboratory for Turbulence and Complex Systems and Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing, 100871, P. R. China

  • Minping Wan

    Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, Shenzhen 518055, China, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China

  • Lian-ping Wang

    Univ of Delaware, Southern University of Science and Technology, China, Univ of Delaware , Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, University of Delaware

  • Shiyi Chen

    Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, State Key Laboratory for Turbulence and Complex Systems and Center for Applie, Department of Mechanics and Aerospace Engineering Southern University of Science and Technology, Shenzhen 518055, China, State Key Laboratory for Turbulence and Complex Syste, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, State Key Laboratory of Turbulence and Complex, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China, State Key Laboratory of Turbulence, Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China, State Key Laboratory for Turbulence and Comple