CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Open Source Meshers: Gmsh, Netgen, CGNS, ...

Structured mesh and boundary layer with Salome

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   July 21, 2011, 10:25
Default Structured mesh and boundary layer with Salome
  #1
New Member
 
Robin
Join Date: Mar 2011
Location: France
Posts: 6
Rep Power: 6
wwrfd is on a distinguished road
Hi everyone,

I'm supposed to make a study on cylindrical shapes using Salome openFOAM coupling.
Problem is I want to make a structured mesh with boundary layers on it. I saw some threads talking about that, but there weren't making any reference to my problem. I understood the process to refine the mesh near the BC walls (I attached some pictures) but my geometry is made of several cylinders crossing each others and I had to use the boolean operation "fuse" to have only one solid that make the fluid volume.

At the intersections of the cylinders, the algorithm of quadrangle mapping doesn't work because I don't have 4 edges (which is logical unfortunatly...) so I wondered if there were a way to project the faces or to do a sketch on the main cylinder (the horizontal one) of the others cylinders to have 4 edges per face instead of using the boolean operation fuse that creates meshing problem (for structured mesh).
I hope I explained it the right way so everybody can understand the problem.

I attached some pictures of my geometry and a structured mesh with a "pseudo" boundary layer I managed to create on a simple cylinder.

Thank you for your replies.

Structuredmesh.jpg

solidbeforeBO.jpg

solideafterBO.jpg

shapeview.jpg
wwrfd is offline   Reply With Quote

Old   December 17, 2011, 02:33
Default
  #2
New Member
 
vasanth kumar chuttu
Join Date: Dec 2011
Posts: 5
Rep Power: 5
vasanthkch is on a distinguished road
Quote:
Originally Posted by wwrfd View Post
Hi everyone,

I'm supposed to make a study on cylindrical shapes using Salome openFOAM coupling.
Problem is I want to make a structured mesh with boundary layers on it. I saw some threads talking about that, but there weren't making any reference to my problem. I understood the process to refine the mesh near the BC walls (I attached some pictures) but my geometry is made of several cylinders crossing each others and I had to use the boolean operation "fuse" to have only one solid that make the fluid volume.

At the intersections of the cylinders, the algorithm of quadrangle mapping doesn't work because I don't have 4 edges (which is logical unfortunatly...) so I wondered if there were a way to project the faces or to do a sketch on the main cylinder (the horizontal one) of the others cylinders to have 4 edges per face instead of using the boolean operation fuse that creates meshing problem (for structured mesh).
I hope I explained it the right way so everybody can understand the problem.

I attached some pictures of my geometry and a structured mesh with a "pseudo" boundary layer I managed to create on a simple cylinder.

Thank you for your replies.

Attachment 8495

Attachment 8496

Attachment 8497

Attachment 8498
hi,
i am doing flow inside a cylinder i have a question how did u mesh that cylinder can please help me im facing problem that is base for my project i am new to this openFoam
vasanthkch is offline   Reply With Quote

Old   December 21, 2011, 06:46
Default
  #3
New Member
 
Robin
Join Date: Mar 2011
Location: France
Posts: 6
Rep Power: 6
wwrfd is on a distinguished road
Quote:
Originally Posted by vasanthkch View Post
hi,
i am doing flow inside a cylinder i have a question how did u mesh that cylinder can please help me im facing problem that is base for my project i am new to this openFoam
Hi, do you also use Salome to mesh the cylinder? Otherwise I would advice you to use Salome only to export the geometry in STL. file, so you can mesh it with SnappyHexMesh, there are excellent tutorials for meshing a cylinder with it, moreover, when I started my project the version 2.0 of openFOAM wasn't released yet, but the last update SnappyHexMesh has been improved and I think it will be perfect for your projet. You have several tutorials to use SnappyHexMesh, may I suggest you to refer to this one: http://openfoamfoorumi.com/wordpress...inenAaltoU.pdf
You can also refer to this thread for snappyHexmesh:
http://www.cfd-online.com/Forums/ope...ture-edge.html

If you really want to do the meshing part with salome, I can write you a small tutorial with screen captures to show you how to do it.

Good luck for your project.

Regards.
wwrfd is offline   Reply With Quote

Old   February 21, 2012, 05:01
Default
  #4
Member
 
Avdeev Evgeniy
Join Date: Jan 2011
Location: Togliatty, Russia
Posts: 52
Blog Entries: 1
Rep Power: 12
j-avdeev will become famous soon enough
Send a message via Skype™ to j-avdeev
Quote:
Originally Posted by wwrfd View Post
If you really want to do the meshing part with salome, I can write you a small tutorial with screen captures to show you how to do it.
Can you made it or post a link to any information around this theme?
Thank you.
j-avdeev is offline   Reply With Quote

Old   April 4, 2012, 03:06
Default
  #5
kid
Senior Member
 
cfdkid
Join Date: Mar 2009
Posts: 133
Rep Power: 8
kid is on a distinguished road
Hello Robin,
Need structured mesh for NACA0012 airfoil. Salome was used to create un-structured mesh, but for airfoil one required structured mesh for capturing boundary layer.

Can you guide me on how to generate structured mesh in Salome? (not snappyHexMesh)

Regards,
CFDkid
kid is offline   Reply With Quote

Old   September 4, 2014, 09:48
Default
  #6
Senior Member
 
ok
Join Date: Oct 2013
Posts: 258
Rep Power: 4
Maimouna is on a distinguished road
[QUOTE=

If you really want to do the meshing part with salome, I can write you a small tutorial with screen captures to show you how to do it.

Good luck for your project.

Regards.[/QUOTE]

Dear Robin,

could you guide me please to mesh flow around circular cylinder using Salome. If you still have that tutorial with screen capture, it would be really grateful to help me please. Or any other tutorial could help me.

Kind regards
Maimouna is offline   Reply With Quote

Old   September 4, 2014, 12:49
Default Tutorial
  #7
New Member
 
Robin
Join Date: Mar 2011
Location: France
Posts: 6
Rep Power: 6
wwrfd is on a distinguished road
Hi,

Very old threat, I assume it's still difficult to generate a structured mesh even with the latest release of Salome? I haven't used it for almost 2 years but I remember how I did it ( I think).

For a cylinder shape it is very easy, you just define a circle split into as much vertices as you want as long as you define 4 edges per surface (to ensure strutured mesh). For this example I just designed a square, and then add vertices at a 45 deg angle and a fixed distance from the center of the square. From that I generated 5 surfaces, used the merging operation (boolean operation) put the same number of elements on vertices to ensure a structured mesh (bijection). Once you get that, you extrud your mesh in one of the axis of your cylinder.

I may check that if I have time to play with it to see what it is, but they made really good improvement so far compared to when I used to use it. I'll upload a short presentation that explains the step that I did at that time. For any complex shapes, I don't really recommend salome if you're doing CFD analysis and need a structured mesh, have you tried Gmsh?

Kind regards.

Robin
wwrfd is offline   Reply With Quote

Old   September 5, 2014, 06:31
Default
  #8
Senior Member
 
ok
Join Date: Oct 2013
Posts: 258
Rep Power: 4
Maimouna is on a distinguished road
Dear Robin,

lots of thanks for your help. I just installed Salome yesterday, I'm still not familiar with it.

If you could try and do the small presentation for that, it would be really grateful.

I myself would like to use Gmesh, but I'm still learning it. If you have such tutorials would help me, I would be really grateful.

Best regards

Maimouna
Maimouna is offline   Reply With Quote

Reply

Tags
boundary layer, cylindrical, openfoam 1.7.1, salome, structured mesh

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
SnappyHexMesh - no layer added bejbro OpenFOAM Mesh Utilities 4 October 16, 2014 19:24
Wind turbine simulation Saturn CFX 34 October 16, 2014 05:27
Boundary layer generation problems ivan_cozza OpenFOAM Native Meshers: snappyHexMesh and Others 0 October 6, 2010 13:47
RPM in Wind Turbine Pankaj CFX 9 November 23, 2009 05:05
Trimmed cell and embedded refinement mesh conversion issues michele OpenFOAM Other Meshers: ICEM, Star, Ansys, Pointwise, GridPro, Ansa, ... 2 July 15, 2005 04:15


All times are GMT -4. The time now is 07:28.