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

[snappyHexMesh] Understanding the Propeller tutorial

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 3, 2014, 12:13
Question Understanding the Propeller tutorial
  #1
New Member
 
Martin
Join Date: Oct 2013
Location: Newcastle
Posts: 21
Rep Power: 9
mahtin360 is on a distinguished road
Hello,

I've recently started with OpenFOAM (2.3.0) and want to simulate rotating propellers.

I'm looking at the propeller tutorial and trying to understand how AMI patches are generated. I've tried to use SHM to do my own geometry but when I look at the two AMI patches, they look quite different. As far as I understand in the propeller tutorial they both come from the innerCylinderSmall geometry and the AMI is created using topoSet?

Could someone explain why if they can be different when I look at my own cylinders in ParaView, aren't the same mesh refinements applied in SHM? Do I have to work with the topoSet and createPatch dicts to work around this or is this a matter of mesh refinment?

thank you for any hints on this
Martin

AMI.jpg

AMI1.jpg
mahtin360 is offline   Reply With Quote

Old   April 5, 2014, 20:36
Default
  #2
Senior Member
 
Pete Bachant
Join Date: Jun 2012
Location: Boston, MA
Posts: 171
Rep Power: 10
pbachant is on a distinguished road
Are you naming them the same way? Make sure you have the explicit feature edge section of the snappyHexMeshDict set correctly, and that your surfaceFeatureExtractDict is also correct. Beyond that, I've had luck increasing the number of feature snap iterations from 10 to around 50.
pbachant is offline   Reply With Quote

Old   April 7, 2014, 07:01
Default
  #3
New Member
 
Martin
Join Date: Oct 2013
Location: Newcastle
Posts: 21
Rep Power: 9
mahtin360 is on a distinguished road
Hi, thanks for your hints.
I've got it working with a new stl file and not specifying explicit feature edges at the moment. I will try increasing the iterations if I run into similar problems while refining further.
Yes, I'm following the tutorial. They both come from my innerCylinderSmall.stl file. I'm actually wondering where exactly the innerCylinderSmall and innerCylinderSmall_slave come from i.e at what stage these are generated and how?
mahtin360 is offline   Reply With Quote

Old   April 7, 2014, 16:30
Default
  #4
Senior Member
 
Pete Bachant
Join Date: Jun 2012
Location: Boston, MA
Posts: 171
Rep Power: 10
pbachant is on a distinguished road
Quote:
Originally Posted by mahtin360 View Post
Hi, thanks for your hints.
I've got it working with a new stl file and not specifying explicit feature edges at the moment. I will try increasing the iterations if I run into similar problems while refining further.
Yes, I'm following the tutorial. They both come from my innerCylinderSmall.stl file. I'm actually wondering where exactly the innerCylinderSmall and innerCylinderSmall_slave come from i.e at what stage these are generated and how?
I believe these are generated with snappyHexMesh, and then AMI1 and AMI2 are created with createPatch.

Last edited by pbachant; April 7, 2014 at 22:37.
pbachant is offline   Reply With Quote

Old   April 9, 2014, 11:47
Default
  #5
New Member
 
Martin
Join Date: Oct 2013
Location: Newcastle
Posts: 21
Rep Power: 9
mahtin360 is on a distinguished road
Yes, I was just wondering if anyone has some more information as to when these are generated as it seemed the two patches came out differently in my case. I'm just wondering why for one of the AMIs the edges are different to the other one.
mahtin360 is offline   Reply With Quote

Reply

Tags
ami patches, propeller, snappyhexmesh

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
Paid help sought for realistic propeller model or tutorial cnd OpenFOAM Running, Solving & CFD 2 February 25, 2019 09:26
Propeller calculation toil CFX 15 May 22, 2017 05:06
Marine propeller tutorial / validation case cagriaydin FLUENT 0 July 28, 2015 11:30
propeller tutorial openfoam_user OpenFOAM Running, Solving & CFD 0 February 8, 2012 05:02
Modelling a propeller tomg STAR-CCM+ 4 April 28, 2011 18:22


All times are GMT -4. The time now is 04:52.