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

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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

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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

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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

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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

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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

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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

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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

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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

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