[General] remove outside part of Isosurface bubble

abalogh · May 23, 2017, 03:55

I have a zero isosurface with two disjoint parts. Basically one bubble inside another bubble. How can I completely remove the outside bubble/isosurface and leave the inside one intact if they have the same scalar values? Slicing through the isosurfaces gives me a peek inside them, but I would like to completely remove the outer layer.

beral · May 23, 2017, 04:13

If one bubble have a value which the other one does not have, you can clip by scalar to remove one of the bubbles.

abalogh · May 23, 2017, 13:15

they all have the same (zero) value.

beral · May 29, 2017, 04:20

If there are complex interwoven structures which have to be separated in Paraview, it may be a good idea to produce a special value (just one more array) while producing the simulation data. Let this value be "InnerBubble" in your case and whenever a point of the inner bubble is simulated, its InnerBubble is set to 1. If a point of the outer bubble is simulated, its InnerBubble is set to -1. Then the bubbles can be separated very easy by the clip filter as mentioned above.

abalogh · May 29, 2017, 14:01

Thanks,

I ended up doing it two different ways. It turns out that the outer zero values correspond to small or zero gradients, and the inner layers correspond to large gradients.
Based on the gradients in one approach I simply changed some of the datavalues. Probably your suggestion would be more appropriate, to use an extra variable instead of changing simulation data values.
I also tried using threshold filter based on gradient calculator in paraview. This worked out nicely, except it slows down the visualization.

May 23, 2017, 03:55	remove outside part of Isosurface bubble	#1
abalogh New Member Andras Balogh Join Date: May 2017 Posts: 3 Rep Power: 9	I have a zero isosurface with two disjoint parts. Basically one bubble inside another bubble. How can I completely remove the outside bubble/isosurface and leave the inside one intact if they have the same scalar values? Slicing through the isosurfaces gives me a peek inside them, but I would like to completely remove the outer layer.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[GAMBIT] Bubble modelling to simulate shape oscillations	akash	ANSYS Meshing & Geometry	6	January 30, 2013 13:17
bubble dynamics in microchannel	arunbaghel	Main CFD Forum	0	December 4, 2012 11:15
isosurface in CFD-Post for transient rotor-stator simulations	blacksoil2012	CFX	1	May 29, 2012 20:07
gas hold up in bubble	Shelly	Main CFD Forum	0	November 13, 2006 01:28
Query on VOF for Bubble rise	Vamsi	Main CFD Forum	0	December 22, 2005 01:02

May 23, 2017, 04:13		#2
beral New Member Join Date: Jan 2017 Location: Germany Posts: 19 Rep Power: 9	If one bubble have a value which the other one does not have, you can clip by scalar to remove one of the bubbles.

May 23, 2017, 13:15		#3
abalogh New Member Andras Balogh Join Date: May 2017 Posts: 3 Rep Power: 9	they all have the same (zero) value.

May 29, 2017, 04:20		#4
beral New Member Join Date: Jan 2017 Location: Germany Posts: 19 Rep Power: 9	If there are complex interwoven structures which have to be separated in Paraview, it may be a good idea to produce a special value (just one more array) while producing the simulation data. Let this value be "InnerBubble" in your case and whenever a point of the inner bubble is simulated, its InnerBubble is set to 1. If a point of the outer bubble is simulated, its InnerBubble is set to -1. Then the bubbles can be separated very easy by the clip filter as mentioned above.

May 29, 2017, 14:01		#5
abalogh New Member Andras Balogh Join Date: May 2017 Posts: 3 Rep Power: 9	Thanks, I ended up doing it two different ways. It turns out that the outer zero values correspond to small or zero gradients, and the inner layers correspond to large gradients. Based on the gradients in one approach I simply changed some of the datavalues. Probably your suggestion would be more appropriate, to use an extra variable instead of changing simulation data values. I also tried using threshold filter based on gradient calculator in paraview. This worked out nicely, except it slows down the visualization.