CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Meshing & Mesh Conversion

[snappyHexMesh] basic understanding of sHM

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 17, 2010, 05:17
Default basic understanding of sHM
  #1
Senior Member
 
Join Date: Aug 2010
Location: Groningen, The Netherlands
Posts: 216
Rep Power: 18
colinB is on a distinguished road
Hi guys,
after working with sHM for a while and didn't get the results that I needed I have to ask you some questions, to get a better basic understanding.

The case I'm working on is comparatively simple.
To simulate the flow of water around a floating structure and get the resulting wave pattern I want to use interFoam.
The geometry of the solid that shall be examined I have as an .stl file and stored in a trisurface folder.
And finally the background mesh is created with blockMesh (simple box with elements of an aspect ratio close to one).
Everything is done according to the guidelines of of.com
So now it comes to the snappyHexMeshDict file where I don't get every parameter, even after reading the manual more than twice.
The questions that arose:

Which is the parameter that defines the location of the stl geometry in the background mesh?
I know there is a parameter called location in mesh, but what exactly is his function and where is the point he is located in the stl file (if this is the right parameter for that issue)

How do I have to understand the splitting parameter?
There is a level specification, but can I assume that level 1 splits one element in 8 sub elements level 2 in 64 and so on?

What has the parameter locationInMesh with the cell removal to do?

I hope these questions are not too basic

thanks for your trouble

Colin

Edit: I got the snappyHexMesh comand running without any errors but viewing the mesh with paraFoam I couldn't find my floating structure within that mesh.

Last edited by colinB; September 17, 2010 at 07:17. Reason: forgott something to mention
colinB is offline   Reply With Quote

Old   October 6, 2010, 09:17
Default
  #2
Senior Member
 
Join Date: Aug 2010
Location: Groningen, The Netherlands
Posts: 216
Rep Power: 18
colinB is on a distinguished road
Hi
for those of you who have the same questions like me,
I could answer some of them and I want to share. I know
that some things might look trivial especially when you have
been working with sHM for some time, but though these
answers might help the one or other user to get little easier into sHM.

How do I locate a stl geometry in my background mesh
generated with blockMesh:

Both meshes have a (0 0 0) coordinate and these will be
on top of each other when combined in the sHM mesh.

How can I view the total mesh after running sHM and
how is the calculation done with the sHM Mesh and
not just with the background mesh:

always use the command: snappyHexMesh -overwrite
and not just snappyHexMesh. This will overwrite the mesh
information in the relevant folders and you can see/calculate
now with the mesh generated by sHM

What is the parameter locationInMesh for:

place this point in the part of the Mesh you want to keep
(I know it is explained very well in the documentation)

so far my cognition
regards Colin
colinB is offline   Reply With Quote

Reply

Tags
basic, knowledge, parameters, shm, snappyhesmeshdict

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[snappyHexMesh] different sHM results on same geometry when everythin is in one or several stl-files. Laika OpenFOAM Meshing & Mesh Conversion 1 September 8, 2016 05:09
[snappyHexMesh] 2D AMI Moving Mesh with sHM; How hard can this be? ADGlassby OpenFOAM Meshing & Mesh Conversion 18 June 18, 2013 07:07
[snappyHexMesh] troubles with sHM and parallel Tobi OpenFOAM Meshing & Mesh Conversion 1 August 30, 2012 18:54
[snappyHexMesh] Multi Region Meshing with sHM marango OpenFOAM Meshing & Mesh Conversion 3 March 27, 2012 01:51
Basic Understanding Abduri CFX 8 March 7, 2009 07:12


All times are GMT -4. The time now is 09:50.