CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Post-Processing

Surface Sampling

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 22, 2014, 11:23
Default Surface Sampling
  #1
Member
 
Join Date: Jul 2012
Location: Wisconsin,USA
Posts: 34
Rep Power: 5
AA29 is on a distinguished road
Dear Foamers,

I have an engine case where I need to extract velocities on different cut planes.
To do that I am using sample utility in OpenFoam with a format raw (which gives the coordinates and the velocity components). Later I am plotting the 2D velocity vectors in Matlab. But since the mesh is not an evenly spaced grid , I am having some issues in creating the contours and vectors.

My question is there a way I could get the velocities on a regular grid (like remapping the sampled velocity on an evenly spaced grid)? Or a surface write format which writes the sampled data at regular intervals given a dx , a dy and start and end points? I am aware that line sampling can do that, but I need surface sampling in this case.

Thanks for your time.
AA29 is offline   Reply With Quote

Old   August 6, 2014, 13:12
Default
  #2
Member
 
Join Date: Jul 2012
Location: Wisconsin,USA
Posts: 34
Rep Power: 5
AA29 is on a distinguished road
Well I had to provide a cloud of points using set sampling to get what I wanted.It works but creating a cloud is not fun, especially if the domain is big and we want to sample at many points.

Thanks !
AA29 is offline   Reply With Quote

Old   August 6, 2014, 13:22
Default
  #3
Member
 
Join Date: Jul 2012
Location: Wisconsin,USA
Posts: 34
Rep Power: 5
AA29 is on a distinguished road
Another question is that when we provide the coordinates of several points to sample, and say a point A(0.5,0.5,0.5) lies outside our solution domain , then the sample utility does not output any value at that point (I am using "raw" write format).

All I want is that OpenFOAM outputs "NaN" values at all those points which lie outside the domain. Does anyone have an idea about how to accomplish this?

Thanks in advance !
AA29 is offline   Reply With Quote

Reply

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
Error : Self intersecting surface mesh, computing intersections & Error : Impossible velan Open Source Meshers: Gmsh, Netgen, CGNS, ... 1 July 14, 2015 05:54
Problems with surface sampling mcarpe OpenFOAM Post-Processing 11 November 9, 2012 12:00
Add additional boundary layers to complex stl surface tobijingles OpenFOAM Native Meshers: snappyHexMesh and Others 1 October 26, 2011 10:45
boundaries with gmshToFoam‏ ouafa Open Source Meshers: Gmsh, Netgen, CGNS, ... 7 May 21, 2010 12:43
free convection heat transfer from a heated horizontal surface through a liquid to a thin cooled fin Kaushik FLUENT 1 May 8, 2000 06:47


All times are GMT -4. The time now is 17:04.