|
[Sponsors] |
![]() |
![]() |
#41 | |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
Quote:
Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 2.3.0 | | \\ / A nd | Web: www.OpenFOAM.org | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; object dynamicMeshDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dynamicFvMesh dynamicMotionSolverFvMesh; motionSolverLibs ("libsixDoFRigidBodyMotion.so"); solver sixDoFRigidBodyMotion; sixDoFRigidBodyMotionCoeffs { patches (CYLINDER); innerDistance 1; // motion area outerDistance 2; // dynamic mesh area mass 9.97; // mass centreOfMass (0 0 0.29); momentOfInertia (0.055 0.055 1); g (0 0 -9.81); orientation ( 1 0 0 0 1 0 0 0 1 ); angularMomentum (0 0 0); rhoName rhoInf; rhoInf 1000; report on; constraints { maxIteration 500; noRotate1 { sixDoFRigidBodyMotionConstraint axis; axis (0 0 1); } noRotate2 { sixDoFRigidBodyMotionConstraint axis; axis (1 0 0); } noRotate3 { sixDoFRigidBodyMotionConstraint axis; axis (0 1 0); } zPlane { sixDoFRigidBodyMotionConstraint plane; normal (0 0 1); } } restraints { verticalSpring1 { sixDoFRigidBodyMotionRestraint linearSpring; anchor (2 0 0);//spring attached point on bottom refAttachmentPt (1 0 0.384);//spring attached point on cylinder stiffness 2.3225; damping 0.109; restLength 1;//? } verticalSpring2 { sixDoFRigidBodyMotionRestraint linearSpring; anchor (0 -2 0);//spring attached point on bottom refAttachmentPt (0 -1 0.384);//spring attached point on cylinder stiffness 2.3225; damping 0.109; restLength 1;//? } verticalSpring3 { sixDoFRigidBodyMotionRestraint linearSpring; anchor (-2 0 0);//spring attached point on bottom refAttachmentPt (-1 0 0.384);//spring attached point on cylinder stiffness 2.3225; damping 0.109; restLength 1;//? } verticalSpring4 { sixDoFRigidBodyMotionRestraint linearSpring; anchor (0 2 0);//spring attached point on bottom refAttachmentPt (0 1 0.384);//spring attached point on cylinder stiffness 2.3225; damping 0.109; restLength 1;//? } } // ************************************************************************* // here is my dynamicMeshDict the only one which I am not sure is the restLength. I have 4 verticalSpring attached on the cylinder Best wishes, Scabbard |
||
![]() |
![]() |
![]() |
![]() |
#42 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Scabbard,
many thanks. What about pointDisplacement file and motionU? |
|
![]() |
![]() |
![]() |
![]() |
#43 | |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
Quote:
Do not need to put motionU in to the 0, MotionScale will be automatically generated. Best wishes, Scabbard Last edited by Scabbard; June 17, 2014 at 05:52. |
||
![]() |
![]() |
![]() |
![]() |
#44 | |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
In my case, I deleated pointDisplacement and pointMotionU, but it gives me this error message
Quote:
What does it mean? What's the problem? Regards |
||
![]() |
![]() |
![]() |
![]() |
#45 |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
||
![]() |
![]() |
![]() |
![]() |
#46 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Scabbard, I'm using OpenFOAM-2.2.2.
|
|
![]() |
![]() |
![]() |
![]() |
#47 |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
||
![]() |
![]() |
![]() |
![]() |
#48 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Scabbard,
I attached you my case. With million of thanks. |
|
![]() |
![]() |
![]() |
![]() |
#49 |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
||
![]() |
![]() |
![]() |
![]() |
#50 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Scabbard,
what mesh tools you used in your case? |
|
![]() |
![]() |
![]() |
![]() |
#51 |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
||
![]() |
![]() |
![]() |
![]() |
#52 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Scabbard,
my running case is following these steps ./Allclean ./Allprepare pimpleDyMFoam |
|
![]() |
![]() |
![]() |
![]() |
#53 |
Member
Join Date: Dec 2013
Location: Newcastle
Posts: 54
Rep Power: 13 ![]() |
||
![]() |
![]() |
![]() |
![]() |
#54 | |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Quote:
no worries, I'll try to solve the problem. Best wishes Maimouna |
||
![]() |
![]() |
![]() |
![]() |
#55 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear OpenFOAM user,
I'm trying to let the cylinder moves in both x and y direction. I'm using for that OF230 and pimpleDyMFoam solver. It's moves in x direction itself and y direction itself. Now, I'm trying to keep it moves in x and y direction naturally at the same time. This is my dynamisMeshDict file Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 2.3.0 | | \\ / A nd | Web: www.OpenFOAM.org | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; object dynamicMeshDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dynamicFvMesh dynamicMotionSolverFvMesh; motionSolverLibs ("libsixDoFRigidBodyMotion.so"); solver sixDoFRigidBodyMotion; sixDoFRigidBodyMotionCoeffs { // D = 1m (r=0.5); L=1m // Volume of cylinder V = D^2*pi/4 * L = 1^2*pi/4 * 1 = 0.25*pi patches (cylinder); innerDistance 0.35; //?? outerDistance 2.5; //?? mass 9.97; // m = 9.97 => rho_cylinder = m/V = 12.6946 [kg/m^3] ??only?? centreOfMass (4 0 0.5); //was (0 0 0.29); (Overall domain bounding box (0 -4 0) (16 4 1)) momentOfInertia (1.4539 1.4539 1.24625);//J = m*(1/12*(3*r^2 + L^2) 1/12*(3*r^2 + L^2) r^2/2) //J = m*(0.14583 0.14583 0.125) g (0 -9.81 0); //was (0 0 -9.81); orientation ( 1 0 0 0 1 0 0 0 1 ); angularMomentum (0 0 0); rhoName rhoInf; rhoInf 1; // rho_cylinder is very small for this report on; constraints { maxIteration 500; noRotate1 { sixDoFRigidBodyMotionConstraint axis; axis (0 0 1); } noRotate2 { sixDoFRigidBodyMotionConstraint axis; axis (1 0 0); } noRotate3 { sixDoFRigidBodyMotionConstraint axis; axis (0 1 0); } // xLine // { // sixDoFRigidBodyMotionConstraint line; // direction (1 0 0); // } // yLine // { // sixDoFRigidBodyMotionConstraint line; // direction (0 1 0); // } // zAxis // { // sixDoFRigidBodyMotionConstraint axis; // axis (0 0 1); // } zPlane { sixDoFRigidBodyMotionConstraint plane; normal (0 0 1); } } restraints //motion is constrained to z=const plane, so linear springs are neaded only for x and y direction. { horisontalSpring { sixDoFRigidBodyMotionRestraint linearSpring; anchor (4 0 0.5); // was (0.2 0 0);//? refAttachmentPt (4 0 0.5); // was (0.092 0 0.384);//spring attached point on cylinder stiffness 4000;//? damping 2;//? restLength 0;//?? } verticalSpring { sixDoFRigidBodyMotionRestraint linearSpring; anchor (4 0 0.5); refAttachmentPt (4 0 0.5); stiffness 4000;//? damping 2;//? restLength 0;//?? } //spring // { // sixDoFRigidBodyMotionRestraint linearSpring; // anchor (4 0 0.5); // was (0.2 0 0);//? // refAttachmentPt (4 0 0.5); // was (0.092 0 0.384);//spring attached point on cylinder // stiffness 4000; //2.3225;// you should calculate it for your problem // damping 2; //0.001;// this may be 0 or calculated for your problem // restLength 0; // } } } // ************************************************************************* // Any answer would be welcomed? Thanks in advanced and regards. Maimouna Last edited by wyldckat; September 15, 2014 at 16:01. Reason: [QUOTE] -> [CODE] |
|
![]() |
![]() |
![]() |
![]() |
#56 | |
New Member
Alireza Heidari
Join Date: Apr 2014
Posts: 5
Rep Power: 12 ![]() |
Quote:
i did the oscillation on cylinder using OF 2.0.1 everything seems ok but i cant valid my result by comparing the lift coeffs. i've downloaded your case but you said it works on OF versions (2.2.2 and 2.3.0) so unfortunately i couldn't run your file and compare it. my problem is how to define measure of omega in ponitDisplacement file. according to the papers lock in occurs in 0.9<F<1.1 that F=f0/fs where f0 is the forced oscillation frequency and fs refers to the Strouhal frequency for the fixed cylinder. in my case Re=100 u=0.004016 d=0.025 St@Re100=0.165 so fs=0.0265 for F=1 f0=fs then omega is 2*pi*0.0265=0.166 is it right way or not? or problem is in my code? Thanks and Regards, alireza heidari. |
||
![]() |
![]() |
![]() |
![]() |
#57 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Alireza,
what's the problem in my case? What's the error you get? Could you please send me your case to have a look? My email: may78may@hotmail.com. Kind regards |
|
![]() |
![]() |
![]() |
![]() |
#58 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,981
Blog Entries: 45
Rep Power: 128 ![]() ![]() ![]() ![]() ![]() ![]() |
Greetings to all!
@Maimouna: It's possible that you've stumbled upon a bug that was present in OpenFOAM 2.3.0 and that might have been already been fixed in 2.3.x. I'm referring to this bug report: http://www.openfoam.org/mantisbt/view.php?id=1284 You might want to try OpenFOAM 2.2.2, since on that bug report it states how a certain feature use to work in 2.2.2, but no longer worked in 2.3.0. In addition, have a look into the tutorial "mesh/moveDynamicMesh/simpleHarmonicMotion" in 2.2.2. It's a very simple tutorial and it makes it a lot easier to test the parameters for restraints, stiffness and so on. The difference is that this motion is based on gravity+springs only and controlled in the file "0/pointDisplacement". This tutorial is no longer present in OpenFOAM 2.3... or at least I can't find it ![]() ![]() Best regards, Bruno
__________________
|
|
![]() |
![]() |
![]() |
![]() |
#59 |
Senior Member
ok
Join Date: Oct 2013
Posts: 346
Rep Power: 14 ![]() |
Dear Bruno,
lots of thanks for your post. Regarding what you posted #58, I swiched my case from OF-2.3.0 to OF-2.2.2. My pointDisplacement file is Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 2.2.2 | | \\ / A nd | Web: www.OpenFOAM.org | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class pointVectorField; location "0.01"; object pointDisplacement; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 0 0 0 0 0]; internalField uniform (0 0 0); boundaryField { cylinder { type sixDoFRigidBodyDisplacement; mass 9.97; centreOfMass (4 0 0.5); momentOfInertia (1.4539 1.4539 1.24625); orientation ( 1 0 0 0 1 0 0 0 1 ); velocity (0 0 0); acceleration (0 0 0); angularMomentum (0 0 0); torque (0 0 0); rhoName rhoInf; rhoInf 1; g (0 -9.81 0); report on; constraints { maxIterations 500; /* noRotate1 { sixDoFRigidBodyMotionConstraint fixedAxis; axis (0 0 1); } noRotate2 { sixDoFRigidBodyMotionConstraint fixedAxis; axis (1 0 0); } noRotate3 { sixDoFRigidBodyMotionConstraint fixedAxis; axis (0 1 0); }*/ fixedLine1 { sixDoFRigidBodyMotionConstraint fixedLine; tolerance 1e-9; relaxationFactor 0.7; fixedLineCoeffs { refPoint (4 0 0.5); direction (1 1 0); } } fixedLine2 { sixDoFRigidBodyMotionConstraint fixedLine; tolerance 1e-9; relaxationFactor 0.7; fixedLineCoeffs { refPoint (4 0 0.5); direction (1 1 0); } } } restraints { horizontalSpring { sixDoFRigidBodyMotionRestraint linearSpring; linearSpringCoeffs { anchor (4 0 0.5); // was (0.2 0 0);//? refAttachmentPt (4 0 0.5); // was (0.092 0 0.384);//spring attached point on cylinder stiffness 4000; //2.3225; damping 2; //0.109; restLength 0;//?? } } verticalSpring { sixDoFRigidBodyMotionRestraint linearSpring; linearSpringCoeffs { anchor (4 0 0.5); refAttachmentPt (4 0 0.5); stiffness 4000;//? damping 2;//? restLength 0; //1;//?? } } /*axialSpring { sixDoFRigidBodyMotionRestraint linearAxialAngularSpring; linearAxialAngularSpringCoeffs { axis (0 0 1); stiffness 700; damping 0.5; referenceOrientation $orientation; } }*/ } omega 1.14040; amplitude (0 0.25 0); value uniform (0 0 0); } top { type empty; } bottom { type empty; } ".*" { type fixedValue; value uniform (0 0 0); } } // ************************************************************************* // Code:
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 2.2.2 | | \\ / A nd | Web: www.OpenFOAM.org | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; object motionProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dynamicFvMesh dynamicMotionSolverFvMesh; motionSolverLibs ("libfvMotionSolvers.so"); solver displacementLaplacian; displacementLaplacianCoeffs { diffusivity inverseDistance (cylinder); } // ************************************************************************* // Thanks and regards. Maimouna Last edited by wyldckat; October 4, 2014 at 12:02. Reason: Changed [QUOTE][/QUOTE] to [CODE][/CODE] |
|
![]() |
![]() |
![]() |
![]() |
#60 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,981
Blog Entries: 45
Rep Power: 128 ![]() ![]() ![]() ![]() ![]() ![]() |
Hi Maimouna,
I'll write this post as a diary of my progress while examining your files and the case at hand. I'm using the case from post #48 as a base, then replaced the files you indicated in the post above. I used OpenFOAM 2.2.x, but should also with 2.2.2... at least I hope so.
Run the attached case to get a feeling of how my thinking in trying to isolate-and-conquer each setting, one at a time. Then start from this case to do small changes. First gradually change and test the "horizontalSpring" parameters to suit your case. Then try adding back the "verticalSpring". Then reduce the inlet speed from 100 to 10 and later to 1. Always run in between changes, to see the results. This way you'll slowly but steadily find how to properly configure your case. Only when things seem to be working properly, should you start turning on the additional features, such as the functions objects and the long run times. Best regards, Bruno
__________________
|
|
![]() |
![]() |
![]() |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Dynamic Mesh "Shadow Wall" | thezack | FLUENT | 0 | June 4, 2013 23:09 |
dynamic mesh for drop interface | IndrajitW | FLUENT | 0 | March 30, 2013 09:03 |
dynamic mesh refinement and rhoCentralFoam | ChrisA | OpenFOAM Running, Solving & CFD | 1 | March 21, 2013 09:00 |
[snappyHexMesh] snappyHexMesh won't work - zeros everywhere! | sc298 | OpenFOAM Meshing & Mesh Conversion | 2 | March 27, 2011 22:11 |
Icemcfd 11: Loss of mesh from surface mesh option? | Joe | CFX | 2 | March 26, 2007 19:10 |