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Chalmers University of Technology, September 2012
Assignment 1CFD with OpenSource Software
Nina Gall Jørgensen
Technical University of DenmarkDepartment of Civil Engineering
09-09-2012
Nina Gall Jørgensen Assignment 1 09-09-2012 1 / 10
Chalmers University of Technology, September 2012
icoFoam: cavity and cavityFine, Re = 10
Pressure
cavity, 400 hexahedra
t = 0.5s, ∆t = 0.005s
cavityFine, 1600 hexahedra
t = 0.7s, ∆t = 0.0025s
Nina Gall Jørgensen Assignment 1 09-09-2012 2 / 10
Chalmers University of Technology, September 2012
icoFoam: cavity and cavityFine, Re = 10
Velocity vectors and graph plot of Ux
cavityFine
Small secondary vortices at thebottom corners.
cavity and cavityFine
Plot Over Line, x = 0.05m
Nina Gall Jørgensen Assignment 1 09-09-2012 3 / 10
Chalmers University of Technology, September 2012
icoFoam: cavityGrade, Re = 10
Velocity contours and graph plot of Ux
Velocity magnitude, t = 0.8s Plot Over Line y, x = 0.01m
Nina Gall Jørgensen Assignment 1 09-09-2012 4 / 10
Chalmers University of Technology, September 2012
icoFoam: cavityHighRe, Re = 100
Change Re by decreasing the kinematic viscosity to ν = 0.001m2/s
Contours and streamlines
Velocity magnitude, t = 2s
Plot Over Line y
x = 0.01m
Nina Gall Jørgensen Assignment 1 09-09-2012 5 / 10
Chalmers University of Technology, September 2012
icoFoam: cavityClipped, Re = 10
Map fields from original solution to changed geometry
Inconsistent mappingData are mapped from cavity case at 0.5s. Field data must exist in the timedirectory of the target case before mapping takes place: cp -r 0 0.5
After mapping change at t = 0.5sfixedWalls U = (0,0,0)
t = 0.5s t = 0.6s
Nina Gall Jørgensen Assignment 1 09-09-2012 6 / 10
Chalmers University of Technology, September 2012
interFoam: damBreak
Simulation of a breaking dam. α1 = 1 is water and α1 = 0 is air
After running blockMesh the setFields is executed for specifying a non-uniforminitial conditon for the phase fracton α1.
Initial conditions for phasefraction α1
Nina Gall Jørgensen Assignment 1 09-09-2012 7 / 10
Chalmers University of Technology, September 2012
interFoam: damBreak
Running simulation with interFoam
Error: Add div((muEff*dev(T(grad(U))))) Gauss linear; to divSchemes inOpenFoam-2.1.x
coarse fine coarse fine
t = 0.25s t = 1s
Nina Gall Jørgensen Assignment 1 09-09-2012 8 / 10
Chalmers University of Technology, September 2012
simpleFoam: pitzDaily
SimpleFoam: Steady-state solver for incompressible, turbulent flow1) blockMesh2) simpleFoam: SIMPLE solution converged in 765 iterations
Filter: streamTracer
Function streamLinein controlDict
Nina Gall Jørgensen Assignment 1 09-09-2012 9 / 10
Chalmers University of Technology, September 2012
simpleFoam: pitzDaily
Utility: yPlusRAS
Write in terminal case directory: yPlusRAS -latestTimeCalculates yPlus values for all wall patches when using RAS turbulence models.
paraFoam:Plot of yPlus at upper andlower wall patches withFilters/Data Analysis/Plot Data
Nina Gall Jørgensen Assignment 1 09-09-2012 10 / 10