شماره ركورد كنفرانس :
4891
عنوان مقاله :
Large Eddy Simulation (LES) for fluid flow modeling of one and two phase flow
Author/Authors :
H Saghi Department of Civil Engineering - Ferdowsi University , M.J Ketabdari Faculty of Marine Technology - Amirkabir University of Technology
كليدواژه :
Navier- Stokes equations , Large Eddy Simulation , Smagorinsky model , staggered grids , dam break , cavity , two phase flow , Volume of fluid method
عنوان كنفرانس :
نهمين كنگره بين المللي مهندسي عمران
چكيده لاتين :
In this paper, the smagorinsky model are applied to simulate the turbulence on fluid flow problems consist of one
and two phase flows and evaluate constant smagorinsky’s coefficient and present suggestion about it to modify
the results. For fluid flow modeling, Momentum and Continuity are the basic equations. The momentum
equations in their final form are known as Navier-Stokes equations. In solution procedure, it needs to decide
where to store the velocity components. In this research, staggered grids are used to evaluate this problem. On
Staggered grids, the velocity components are stored at the cell face and the scalar variables such as pressure are
stored at the central nodes. There are several methods for modeling of free surface flows. These methods are
categorized as surface tracking and surface capturing methods. The Volume of Fluid (VOF) method is one of the
surfaces capturing method. In this research, incompressible N-S equation solved using Large Eddy Simulation.
Navier-Stokes equations are solved using SIMPLE method and VOF method is applied for free surface modeling.
The numerical scheme is validated by simulating Lid-driven cavity flow and dam break modeling. Finally,
Comparison of horizontal and vertical velocities at various Reynolds numbers for Cavity test and dam break that
are samples of one and two phase flows for different quantity of constant smagorinsky’s coefficient were
performed. The results show that application of Smagorinsky’s coefficient between [0.5-0.8] present the best
results in cavity as a one phase flow problem. But its efficiency is negligible in two phase flow problems such as
dam break modeling.