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October 11, 2020, 09:27 |
DPMFoam - Periodic boundary condition
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#1 |
New Member
Rodrigo
Join Date: Oct 2020
Posts: 1
Rep Power: 0 |
I am new in OpenFoam and I need to track a cloud of particles in a channel with periodic boundary conditions. I have two main problems:
1. The cyclic boundary condition looks not working for particles. They stick on the outlet boundary. 2. The particle's flow slowing down over time. I have read that this can be solved by adding fvOptions, but I don't know how to do that. blockMeshDict Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2006 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; object blockMeshDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // scale 1; vertices ( (0 0 0) (10 0 0) (10 1 0) (0 1 0) (0 0 2) (10 0 2) (10 1 2) (0 1 2) ); blocks ( hex (0 1 2 3 4 5 6 7) (90 50 1) simpleGrading (1 1 1) ); edges ( ); boundary ( inlet { type cyclic; neighbourPatch outlet; transform translational; separationVector (10 0 0); faces ( (4 7 3 0) ); } outlet { type cyclic; neighbourPatch inlet; transform translational; separationVector (-10 0 0); faces ( (5 1 2 6) ); } top { type wall; faces ( (7 6 2 3) ); } bottom { type wall; faces ( (0 1 5 4) ); } walls { type wall; faces ( (4 5 6 7) (0 3 2 1) ); } ); // ************************************************************************* // Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2006 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object kinematicCloudProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // solution { active true; coupled true; transient yes; cellValueSourceCorrection off; interpolationSchemes { rho.air cell; U.air cellPoint; mu.air cell; } integrationSchemes { U Euler; } sourceTerms { schemes { U semiImplicit 1; } } } constantProperties { parcelTypeId 1; rhoMin 2; minParcelMass 1.04e-6; rho0 2; youngsModulus 1e8; poissonsRatio 0.35; constantVolume true; alphaMax 0.99; } subModels { particleForces { ErgunWenYuDrag { alphac alpha.air; } gravity; } injectionModels { model1 { type manualInjection; massTotal 0; parcelBasisType fixed; nParticle 1; SOI 0; positionsFile "kinematicCloudPositions"; U0 (0.5 0 0); sizeDistribution { type fixedValue; fixedValueDistribution { value 0.01; } } } } dispersionModel none; patchInteractionModel standardWallInteraction; StandardWallInteractionCoeffs { type rebound; e 0.97; mu 0.09; } heatTransferModel none; surfaceFilmModel none; collisionModel pairCollision; pairCollisionCoeffs { maxInteractionDistance 0.0025; writeReferredParticleCloud no; pairModel pairSpringSliderDashpot; pairSpringSliderDashpotCoeffs { useEquivalentSize no; alpha 0.02; b 1.5; mu 0.10; cohesionEnergyDensity 0; collisionResolutionSteps 12; }; wallModel wallSpringSliderDashpot; wallSpringSliderDashpotCoeffs { useEquivalentSize no; collisionResolutionSteps 12; youngsModulus 1e8; poissonsRatio 0.23; alpha 0.01; b 1.5; mu 0.09; cohesionEnergyDensity 0; }; U U.air; } stochasticCollisionModel none; radiation off; } cloudFunctions {} // ************************************************************************* // Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2006 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format binary; class volVectorField; location "0"; object U.air; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 -1 0 0 0 0]; internalField uniform (1 0 0); boundaryField { walls { type noSlip; } top { type noSlip; } bottom { type noSlip; } outlet { type cyclic; } inlet { type cyclic; } } // ************************************************************************* // Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2006 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class volScalarField; object p; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 -2 0 0 0 0]; internalField uniform 0; boundaryField { walls { type fixedFluxPressure; phi phi.air; value $internalField; } inlet { type cyclic; } outlet { type cyclic; } top { type fixedFluxPressure; phi phi.air; value $internalField; } bottom { type fixedFluxPressure; phi phi.air; value $internalField; } } // ************************************************************************* // |
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October 14, 2020, 02:33 |
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#2 |
Member
Join Date: Sep 2010
Location: Leipzig, Germany
Posts: 93
Rep Power: 15 |
1) One guess: I don't know what happens because you specified both, a patchInteractionModel and a collisionModel? Maybe you should switch one of them off.
2) As you have no boundary condition that keeps pressure/velocity constant at some patch, the coupling of the parcels with the flow's momentum in combination with their energy loss due to collisions should slowly decelerate the flow. You can try turning off "coupled" in kinematicCloudProperties and see if there is a change. |
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