
[Sponsors] 
May 28, 2013, 03:17 
Problem with circle sampling type, of Sample utility

#1 
New Member
nicolas
Join Date: Oct 2009
Posts: 24
Rep Power: 8 
Hi,
I am trying to use the sample utility to extract data along a circular line. To do so, I am using the "circle" sampling type. The problem that I have is that in the first column of the output file, where theta should be, I always get zeros. This "circle" type is not listed in the users guide, so the following dictionary that I am using is a result of trial and error, and by looking at the source sampleSet.H. So I am not sure if I am using all the right parameters. This is the sampleDict that I am using: Code:
interpolationScheme cell; setFormat raw; sets ( alongCircWall { type circle; origin (0 0 0); // Origin (x, y, z) in global cartesian coordinates circleAxis (1 0 0); // Axis of the circle startPoint (0 0 0.6); // Defines start point on circle (x, y, z) in global cartesian coordinates dTheta 2; // Sampling interval in degrees about the origin axis x; // This I don't know why is needed, but needs to be defined as well? } ); fields ( T ); Regards, Nicolas 

May 30, 2013, 08:14 
Figured it out

#2 
New Member
nicolas
Join Date: Oct 2009
Posts: 24
Rep Power: 8 
I have figured it out after all.
The problem was with the "axis x;" parameter. This parameter defines which coordinates are to be written in the output file for each point. You can select, x, y, z, for a single coordinate, or xyz for all coordinates. Since writing the angle theta is not an option, I used xyz to get the coordinates of each point along the circle, and some awk commands to calculate the angle. It is also worth notting that this sampling type writes out the data along the circle in a weird order. So before plotting the values of a field versus the angle theta, you need to take a close look in the order in which the points are written. Nicolas 

February 23, 2015, 12:01 
Circle sampling on boundary patch

#3 
New Member
Join Date: Jun 2012
Posts: 2
Rep Power: 0 
Hello all,
i know this thread is a bit older but my question fits in this thread very well. I try to use the circle sample to get circular distributed values from a boundary patch (e.g. wallheatflux) from a pipe. The problem is when I set dTheta=1 for example I do not receive 360 values from 360 points, I just get around 50 values from 50 points. For the remaining points I get the message: Code:
> FOAM Warning : From function void circleSet::calcSamples(DynamicList<point>&, DynamicList<label>&, DynamicList<label>&, DynamicList<label>&, DynamicList<scalar>&) const in file sampledSet/circle/circleSet.C at line 128 Unable to find cell at point id 45 at location (0.0248137 0.00304673 0.5) So how could it be, that OF finds no cells for interpolation at most points? Thanks for help. Regards, Daniel Last edited by daniel54431; February 24, 2015 at 06:51. 

Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
simpleFoam: problem with the U file  samiam1000  OpenFOAM Running, Solving & CFD  5  November 10, 2015 16:47 
sample utility problem  And  OpenFOAM PostProcessing  36  May 20, 2014 08:50 
Floating Point Exception  wrong boundaries or general PC problem? – OF 1.6 extend   A.Wendy  OpenFOAM  0  February 27, 2013 05:50 
turbulent jet simulation  antonio_ing  OpenFOAM Running, Solving & CFD  5  September 16, 2010 02:31 
buoyantSimpleRadiationFoam  msarkar  OpenFOAM  0  February 15, 2010 07:22 