Evaluation of sub grid scale and local wall models in Large-eddy simulations of separated flow

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding

Abstract

The performance of the Sub Grid Scale models is studied by simulating a separated flow over a wavy channel. The first and second order statistical moments of the resolved velocities obtained by using Large-Eddy simulations at different mesh resolutions are compared with Direct Numerical Simulations data. The effectiveness of modeling the wall stresses by using local log-law is then tested on a relatively coarse grid. The results exhibit a good agreement between highly-resolved Large Eddy Simulations and Direct Numerical Simulations data regardless the Sub Grid Scale models. However, the agreement is less satisfactory with relatively coarse grid without using any wall models and the differences between Sub Grid Scale models are distinguishable. Using local wall model returned the basic flow topology and reduced significantly the differences between the coarse meshed Large-Eddy Simulations and Direct Numerical Simulations data. The results show that the ability of local wall model to predict the separation zone depends strongly on its implementation way.

Details

Authors
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Fluid Mechanics and Acoustics
Original languageEnglish
Title of host publication2nd Symposium on OpenFOAM® in Wind Energy
EditorsMatthew J. Churchfield
PublisherEDP Sciences
Number of pages11
Publication statusPublished - 2015 Oct 16
Publication categoryResearch
Peer-reviewedYes
EventSecond Symposium on OpenFOAM® in Wind Energy - Boulder, Colorado, United States
Duration: 2014 May 192014 May 21
http://wind.nrel.gov/2ndSOWE/index.html

Publication series

NameE3S Web of Conferences
PublisherEDP Sciences
Volume5

Conference

ConferenceSecond Symposium on OpenFOAM® in Wind Energy
Abbreviated titleSOWE
CountryUnited States
CityBoulder, Colorado
Period2014/05/192014/05/21
Internet address