|
[Sponsors] |
boundary condition for zerothickness surface :( |
|
LinkBack | Thread Tools | Search this Thread | Display Modes |
April 15, 2015, 09:05 |
boundary condition for zerothickness surface :(
|
#1 |
Member
Naresh Yathuru
Join Date: Feb 2015
Posts: 66
Rep Power: 11 |
Hi Foamers,
sorry for restarting the thread again. I need to implement baffles in my case. i have some basic question can some one please help me. I m having a zero thickness surface in my geometry and i have read a lot of posts regarding how to implement baffles which helped me create a mesh with baffles in snappyHexMesh. (thanks to the changes in snappyhexmesh) code in snappyHexmesh, refinementsurfaces Code:
table { level (2 2); faceZone table; // Create baffles for all faces on the surface faceType baffle; cellZone table; cellZoneInside inside; } and i have checked in the polymesh/boundary folder two boundaries are created of type wall. Code:
table { type wall; inGroups 1(wall); nFaces 588; startFace 653617; } table_slave { type wall; inGroups 1(wall); nFaces 588; startFace 654205; } 1.How can i define B.C to these patches like U,P,K,epsilon 2. do i have to make a folder for "createbafflesDict" to specify boundary conditions or can i specify B.C like for other patches? 3. last and much important question is can i spesify different boundary conditions for the master and slave patch similar to twosidedwall in fluent? I have looked in to couple of tutorials but could not get a clear answer. I m using OF 2.3.0 I m banging my head on the wall. could someone please help me. Regards, Naresh [ Moderator note: Moved post from http://www.cfd-online.com/Forums/ope...nal-faces.html ] Last edited by wyldckat; October 24, 2015 at 17:23. Reason: see "Moderator note:" |
|
April 28, 2015, 13:58 |
boundary condition for zerothickness surface :(
|
#2 |
Member
Naresh Yathuru
Join Date: Feb 2015
Posts: 66
Rep Power: 11 |
Hi Foamers,
I have a case with zero thickness sucface inside my domain. I innitially thought that i need to have createBafflesDict then i came to know that i can create baffles using STL files in the snappyHexMesh. thanks to SHM. Now i m kind of stuck trying to set booundary conditions for the master and slave patches ,where to specify the B.C? can somebody please help me. Code:
// Which of the steps to run castellatedMesh true; // make basic mesh ? snap true; // decide to snap back to surface ? addLayers false; // decide to add viscous layers ? geometry // Load in STL files here { /*baffle { type searchablePlate; origin (2.4 1.8 0.8); span (1.2 2.7 0.8); regions { region0 { name baffle; } } }*/ inlet.stl {type triSurfaceMesh; name inlet;} outlet.stl {type triSurfaceMesh; name outlet;} heater.stl {type triSurfaceMesh; name heater;} roomwall.stl {type triSurfaceMesh; name roomwall;} roof.stl {type triSurfaceMesh; name roof;} floor.stl {type triSurfaceMesh; name floor;} window.stl {type triSurfaceMesh; name window;} table.stl {type triSurfaceMesh; name table;} man1.stl {type triSurfaceMesh; name man1;} man2new.stl {type triSurfaceMesh; name man2new;} //fullgeomnew.stl {type triSurfaceMesh; name fullgeomnew;} //mergedwithouttable.stl {type triSurfaceMesh; name mergedwithouttable;} //refinementBox {type searchableBox; min (-2 -2 6); max (7 5 -2);} }; castellatedMeshControls { maxLocalCells 500000; //max cells per CPU core maxGlobalCells 4000000; //max cells to use before mesh deletion step minRefinementCells 10; //was 0 - zero means no bad cells are allowed during refinement stages maxLoadUnbalance 0.10; nCellsBetweenLevels 3; // expansion factor between each high & low refinement zone // Explicit feature edge refinement // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ features // taken from STL from each .eMesh file created by "SurfaceFeatureExtract" command ( {file "inlet.eMesh"; level 5;} {file "outlet.eMesh"; level 3;} {file "roomwall.eMesh"; level 3;} {file "heater.eMesh"; level 2;} {file "roof.eMesh"; level 1;} {file "floor.eMesh"; level 2;} {file "window.eMesh"; level 3;} {file "table.eMesh"; level 3;} {file "man1.eMesh"; level 2;} {file "man2new.eMesh"; level 3;} //{file "mergedwithouttable.eMesh"; level 3;} ); // Surface based refinement // ~~~~~~~~~~~~~~~~~~~~~~~~ refinementSurfaces // Surface-wise min and max refinement level { inlet { level (5 5);//faceZone inlet;cellZone inlet;cellZoneInside inside; } // was 0 0 outlet { level (3 3);//faceZone outlet;cellZone outlet;cellZoneInside inside; } roomwall { level (3 3);//faceZone roomwall;cellZone roomwall;cellZoneInside inside; } //was 3 3 heater { level (2 2);//faceZone heater;cellZone heater;cellZoneInside inside; } // was 4 4 roof { level (2 2);///faceZone roof;cellZone roof;cellZoneInside inside; } floor { level (2 2);//faceZone floor;cellZone floor;cellZoneInside inside; } window { level (3 3);//faceZone window;cellZone window;cellZoneInside inside; } //table { //level (0 0);//faceZone table;cellZone table;cellZoneInside inside; //} man1 { level (3 3);//faceZone man1;cellZone man1;cellZoneInside inside; } man2new { level (3 3);//faceZone man2;cellZone man2;cellZoneInside inside; } //baffle {level (3 3);} table { level (3 3); faceZone table; // Create baffles for all faces on the surface faceType baffle; cellZone table; cellZoneInside inside; } } resolveFeatureAngle 30; // (before 80) .Resolve sharp angles // Default 30 //refinementRegions // In descending levels of fine-ness //{fullgeomnew //{mode inside;levels ((0.3 3));}} //error: shell mergedtest is suitable for inside mode. //{mode distance; levels ((0.01 4) (0.03 3) (0.1 2));}} // was ((0.001 4) (0.003 3) (0.01 2)) //when i tried like this refinementRegions{} //the whole geometry is meshed and the cell are not removed.*/ locationInMesh (1 1 1); //to decide which side of mesh to keep ** allowFreeStandingZoneFaces true; // before true } // Settings for the snapping. snapControls { nSmoothPatch 5;// before 3 tolerance 1.0; // before 2 nSolveIter 50;// before 30 nRelaxIter 10; //before 5 nFeatureSnapIter 25; // default is 10 // New settings from openfoam 2.2 onwards for SHMesh implicitFeatureSnap false; // default is false - detects without doing surfaceFeatureExtract explicitFeatureSnap true; // default is true multiRegionFeatureSnap true; // deafault is false - detects features between multiple surfaces } I have looked into some tutorials but each tutorials has a different style of implementing the baffles. so i could not able to find it myself. I m desperate for help. Thank you , regards, Naresh |
|
April 30, 2015, 13:40 |
|
#3 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Quick answer: Study the tutorial cases "compressible/rhoPimpleDyMFoam/annularThermalMixer" and "incompressible/pimpleFoam/TJunctionFan".
Hints:
|
|
May 4, 2015, 05:26 |
|
#4 |
Member
Naresh Yathuru
Join Date: Feb 2015
Posts: 66
Rep Power: 11 |
Dear Bruno,
Thank you for your reply. I will check it out. Regards, Naresh Yathuru |
|
September 19, 2016, 05:35 |
|
#5 |
Member
Naresh Yathuru
Join Date: Feb 2015
Posts: 66
Rep Power: 11 |
Hello foamers,
I took me a while to update this post. I was not successful so I tried a very simple geometry of a box with a zero thickness surface inside. i created the geometry in salome.Exported geometry as stl files and meshed in snappyHexMesh. I used the "facetype baffles" in snappy hex mesh to create baffle. I have the following questions: 1. After meshing it shows the master and slave boundary in polymesh/boundary files. how to set boundary conditions for these surfaces in 0 folder? Am I missing something. There is no tutorials for the method where snappyhexmesh is used to create baffles. I have tried the tutorials Tjunctionfan and thermal baffles tutorials but they use createbafflesDict. but I want to generate baffles for the geometry stl file i created in Salome. When I triedto use my stl files in createbafflesdict there was snapping problem. I created stairscasestep mesh. Could someone through some light. I m stuck at this point. I m using OpenFoam 2.3.0 regards, Naresh |
|
September 29, 2016, 17:37 |
|
#6 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,982
Blog Entries: 45
Rep Power: 128 |
Quick answers:
__________________
|
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
sliding mesh problem in CFX | Saima | CFX | 46 | September 11, 2021 08:38 |
Time dependant pressure boundary condition | yosuke1984 | OpenFOAM Verification & Validation | 3 | May 6, 2015 07:16 |
Creating surface concentration boundary condition | MachZero | FLUENT | 5 | February 26, 2014 15:37 |
Radiation interface | hinca | CFX | 15 | January 26, 2014 18:11 |
boundary condition at free surface | mike | Fidelity CFD | 3 | June 8, 2006 07:23 |