A New Two-Scale Decomposition Approach for Large-Eddy Simulation of Turbulent Flows

Turbulent flows;Large eddy simulations;Subgrid-scale modeling

Kemenov, Konstantin A. ; Aerospace Engineering

University:Georgia Institute of Technology

Department:Aerospace Engineering

关键词: Turbulent flows;    Large eddy simulations;    Subgrid-scale modeling;   

Others  :  https://smartech.gatech.edu/bitstream/1853/11520/1/kemenov_konstantin_a_200608_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

A novel computational approach, Two Level Simulation (TLS), was developed based on the explicit reconstruction of the small-scale velocity by solving the small-scale governing equations on the domain with reduced dimension representing a collection of one-dimensional linesembedded in the three-dimensional flow domain. A coupled system of equations, that is not based on an eddy-viscosity hypothesis, was derived based on the decomposition of flow variables into the large-scale and the small-scale components without introducing the concept of filtering. Simplified treatment of the small-scale equations was proposed based on modeling of the small-scale advective derivatives and the small-scale dissipative terms in the directions orthogonal to the lines. TLS approach was tested to simulate benchmark cases of turbulent flows, including forced isotropic turbulence, mixing layers and well-developed channel flow, and demonstrated good capabilities to capture turbulent flow features using relatively coarse grids.