Simulation of heat and mass transfer in turbulent channel flow using the spectral-element method: effect of spatial resolution

All-Russian Conference with the School for Young Scientists “Thermophysics and Physical Hydrodynamics –2016”

Ryzhenkov, V.^1,2 ; Ivashchenko, V.^1,2 ; Vinuesa, R.^3,4 ; Mullyadzhanov, R.^1,2

Institute of Thermophysics, SB, RAS, Novosibirsk, Russia^1

Novosibirsk State University, Novosibirsk, Russia^2

Linné FLOW Centre, KTH Mechanics, Sweden^3

Swedish E-Science Research Centre (SeRC), Stockholm, Sweden^4

关键词: Dynamic Smagorinsky models;    Governing equations;    Heat and mass transfer;    Spatial resolution;    Spectral element method;    Temperature profiles;    Time-averaged velocity;    Turbulent channel flows;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/754/6/062009/pdf
DOI  :  10.1088/1742-6596/754/6/062009

来源: IOP

【 摘 要 】

We use the open-source code nek5000 to assess the accuracy of high-order spectral element large-eddy simulations (LES) of a turbulent channel flow depending on the spatial resolution compared to the direct numerical simulation (DNS). The Reynolds number Re = 6800 is considered based on the bulk velocity and half-width of the channel. The filtered governing equations are closed with the dynamic Smagorinsky model for subgrid stresses and heat flux. The results show very good agreement between LES and DNS for time-averaged velocity and temperature profiles and their fluctuations. Even the coarse LES grid which contains around 30 times less points than the DNS one provided predictions of the friction velocity within 2.0% accuracy interval.