[General] unwrap cylinder slice to flat plane

openfoam_user · May 5, 2017, 04:44

Dear ParaView users,

I use ParaView version 5.3.

I cut my data with a slice (cylinder type).

I would like to unwrap the cylinder slice to a flat plane !
I need your help to achieve this task.

Thanks a lot in advance for your advices.

Best regards,
Stéphane

openfoam_user · May 5, 2017, 08:49

sorry

unwarp

Stéphane

Joshua14 · May 5, 2017, 10:07

Stéphane,

The following steps should allow you to unwrap a cylinder based around the origin.

1. Clip surface such that you do split the geometry in half(semi circle) but not at origin, offset by 0.0001.
2. Use a calculator filter
3. Make sure Attribute Mode is set on "Point Data"
4. Select "Coordinate Results"
5. Use something along the lines of
sqrt(coordsX^2+coordsY^2)*iHat+tan^-1(coordsX/coordsY)*jHat+coordsZ*kHat

Hope this helps.

Joshua

openfoam_user · May 5, 2017, 10:21

Hi Joshua,
Thank you for your help!

But it seems to be something wrong with your for formula :
sqrt(coordsX^2+coordsY^2)*iHat+tan^-1(coordsX/coordsY)*jHat+coordsZ*kHat

Regards,
Stephane.

Joshua14 · May 5, 2017, 10:28

Stéphane,

What appears to be wrong with the formula? If you geometry is oriented differently then you will need to interchange the x, y, and z axis in the equation.

Joshua

openfoam_user · May 5, 2017, 10:50

Hi Joshua,
Sorry, your formula is right.

With the below formula, the 2D plane will be located at X=0 and the width (Y-direction) will measure half-circumference.

0*iHat+atan(coordsX/coordsY)*(coordsX^2+coordsY^2)^(1/2)*jHat+coordsZ*kHat

Thanks again for your quick help.

Best regards,
Stephane.

May 5, 2017, 04:44	unwrap cylinder slice to flat plane	#1
openfoam_user Senior Member stephane sanchi Join Date: Mar 2009 Posts: 314 Rep Power: 18	Dear ParaView users, I use ParaView version 5.3. I cut my data with a slice (cylinder type). I would like to unwrap the cylinder slice to a flat plane ! I need your help to achieve this task. Thanks a lot in advance for your advices. Best regards, Stéphane

May 5, 2017, 10:07		#3
Joshua14 Member Joshua Join Date: Dec 2016 Location: St. Louis, Missouri Posts: 91 Rep Power: 9	Stéphane, The following steps should allow you to unwrap a cylinder based around the origin. 1. Clip surface such that you do split the geometry in half(semi circle) but not at origin, offset by 0.0001. 2. Use a calculator filter 3. Make sure Attribute Mode is set on "Point Data" 4. Select "Coordinate Results" 5. Use something along the lines of sqrt(coordsX^2+coordsY^2)iHat+tan^-1(coordsX/coordsY)jHat+coordsZ*kHat Hope this helps. Joshua Swempa likes this.

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May 5, 2017, 08:49		#2
openfoam_user Senior Member stephane sanchi Join Date: Mar 2009 Posts: 314 Rep Power: 18	sorry unwarp Stéphane

May 5, 2017, 10:21		#4
openfoam_user Senior Member stephane sanchi Join Date: Mar 2009 Posts: 314 Rep Power: 18	Hi Joshua, Thank you for your help! But it seems to be something wrong with your for formula : sqrt(coordsX^2+coordsY^2)iHat+tan^-1(coordsX/coordsY)jHat+coordsZ*kHat Regards, Stephane.

May 5, 2017, 10:28		#5
Joshua14 Member Joshua Join Date: Dec 2016 Location: St. Louis, Missouri Posts: 91 Rep Power: 9	Stéphane, What appears to be wrong with the formula? If you geometry is oriented differently then you will need to interchange the x, y, and z axis in the equation. Joshua

May 5, 2017, 10:50		#6
openfoam_user Senior Member stephane sanchi Join Date: Mar 2009 Posts: 314 Rep Power: 18	Hi Joshua, Sorry, your formula is right. With the below formula, the 2D plane will be located at X=0 and the width (Y-direction) will measure half-circumference. 0iHat+atan(coordsX/coordsY)(coordsX^2+coordsY^2)^(1/2)jHat+coordsZkHat Thanks again for your quick help. Best regards, Stephane.