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How to select all boundaries in a particular plane
Posted Dec 21, 2009, 5:37 p.m. EST Low-Frequency Electromagnetics, Fluid & Heat, Microfluidics, Geometry, Parameters, Variables, & Functions 4 Replies
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Hi - is it possible to select all boundaries lying in a certain plane?
Problem description:
I am trying to simulate a MEMS structure where ontop of a thin membrane an "integrated-circuit-like" structure is fabricated which consists of 2 metal layers and an insulator, each of them around 50nm thick and structured, to yield (many) elements with 10s of micrometer dimensions.
In order to mesh the structure I intend to mesh a 2D boundary first using the 'Free mesher' and use the 'Swept mesher' to extend the mesh to 3D. Since there are many internal boundaries (around 200) selecting them manually is shear impossible, or at least inefficient.
What I would like to be able to do is define a 'Working Plane' and select all boundaries in that plane to mesh, but this doesn't work.
What would also be okay is to hide everything outsid a certain z-range, but I did not find a way to do so.
Being able to 'Supress' all but two domains and select the internal boundaries between the remaining two domains would help enormously, but I did not get that to work either. In an earlier design with only 2 domains the trick of selecting all internal boundaries plus the one remaining worked fine.
Any ideas of how I could select boundaries in a particular plane would be highly apprechiated.
Thanks in advance and best regards,
Kurt
Problem description:
I am trying to simulate a MEMS structure where ontop of a thin membrane an "integrated-circuit-like" structure is fabricated which consists of 2 metal layers and an insulator, each of them around 50nm thick and structured, to yield (many) elements with 10s of micrometer dimensions.
In order to mesh the structure I intend to mesh a 2D boundary first using the 'Free mesher' and use the 'Swept mesher' to extend the mesh to 3D. Since there are many internal boundaries (around 200) selecting them manually is shear impossible, or at least inefficient.
What I would like to be able to do is define a 'Working Plane' and select all boundaries in that plane to mesh, but this doesn't work.
What would also be okay is to hide everything outsid a certain z-range, but I did not find a way to do so.
Being able to 'Supress' all but two domains and select the internal boundaries between the remaining two domains would help enormously, but I did not get that to work either. In an earlier design with only 2 domains the trick of selecting all internal boundaries plus the one remaining worked fine.
Any ideas of how I could select boundaries in a particular plane would be highly apprechiated.
Thanks in advance and best regards,
Kurt
4 Replies Last Post Jan 4, 2010, 3:53 p.m. EST
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Posted:
1 decade ago
Hi Kurt
I agree I also ahve problems selecting items especially for complex volumes from CAD "engineering" cases, with hundreds or even tousends of surfaces. The best way I know is to use the "box" select, I beleive there is another or a few other discussions about this, try a search on the forum.
In a few words I use the 3D to orient my object then I deselect the "rotate" and I "box" the items. In 2D "boxing" is by default, in 3D you have the left mouse click that will rotate your object by default, you need to turn this off (top icon left border side of your grahics window).
You also have the "select sequentialy or select all" icons, i.e. to fetch an edge or a surface I click on a node sevral times while this toggels through the different edges arriving on the node, respectively faces arriving on an edge, or I can elect all items.
Definitions: "box" for me menas selecting with a "box" appearing i.e. right click top let drag bottom right release richt click.
In some CAD software the behaviour is different if you drag top/left down bottom/right = select only fully encircled items , while bottom/right up-to top/left = is selecting all items touched. This si not implemented in COMSOL, but it would be handy ...
Good luck
Ivar
I agree I also ahve problems selecting items especially for complex volumes from CAD "engineering" cases, with hundreds or even tousends of surfaces. The best way I know is to use the "box" select, I beleive there is another or a few other discussions about this, try a search on the forum.
In a few words I use the 3D to orient my object then I deselect the "rotate" and I "box" the items. In 2D "boxing" is by default, in 3D you have the left mouse click that will rotate your object by default, you need to turn this off (top icon left border side of your grahics window).
You also have the "select sequentialy or select all" icons, i.e. to fetch an edge or a surface I click on a node sevral times while this toggels through the different edges arriving on the node, respectively faces arriving on an edge, or I can elect all items.
Definitions: "box" for me menas selecting with a "box" appearing i.e. right click top let drag bottom right release richt click.
In some CAD software the behaviour is different if you drag top/left down bottom/right = select only fully encircled items , while bottom/right up-to top/left = is selecting all items touched. This si not implemented in COMSOL, but it would be handy ...
Good luck
Ivar
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Posted:
1 decade ago
K.P., it has been my experience that in version 3.5a and older, you must activate one boundary at at time with the mouse. After you have done this once, you can use some grouping techniques from one boundary condition and apply to another. For example, in my work, a wall boundary between a solid and liquid that is used for convective heat transfer is often used for the wall condition in both the momentum and energy equations.
This does not help you now, but version 4 has a new feature whereby you can box a view in 3D, and all the surfaces affected by the boxed view can by specified at once, which is very handy and time saving when specifying boundary conditions.
This does not help you now, but version 4 has a new feature whereby you can box a view in 3D, and all the surfaces affected by the boxed view can by specified at once, which is very handy and time saving when specifying boundary conditions.
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Posted:
1 decade ago
Hi James and Kurt
Well as I said just above, in 3D you have the box option it is there, (I needed some tips from support to find it, hadnt read the "what's new" well enough ;) in 3D as by default, "boxing" is off in favour of pan/rotate.
In fact, there are may if these icons, that are rapidly forgotten, but in fact very useful, they are slightly different in 2D and 3D.
Take a look of some of my "often forgotten favorites" on the screen capture attached below, and take a look at the "beginners guide" as I did ;)
Merry Xmas
Ivar
Well as I said just above, in 3D you have the box option it is there, (I needed some tips from support to find it, hadnt read the "what's new" well enough ;) in 3D as by default, "boxing" is off in favour of pan/rotate.
In fact, there are may if these icons, that are rapidly forgotten, but in fact very useful, they are slightly different in 2D and 3D.
Take a look of some of my "often forgotten favorites" on the screen capture attached below, and take a look at the "beginners guide" as I did ;)
Merry Xmas
Ivar
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Posted:
1 decade ago
Hi - thanks for your answers and happy new year.
The box-selection is sort of handy, but in my case I am also selecting boundaries that are not in a particular plane, so this does not solve my problem.
I tried to use 'Supress Domains' before, but upon changing to the 'Free mesher' the surpressed domains are "unsurpressed" and everything is shown again. Interestingly, using the 'Hide Selected Object' icon (see Ivar's jpg) did help a lot, as by using this icon to hide domains allowed me to select the desired boundaries (which are the internal boundaries still shown after one domain was hidden). It's not very convenient but it should do until version 4 is released.
Reading the Beginners guide did also help to learn about 'Confirming Selections' - which is also very handy.
Thanks a lot,
Kurt
The box-selection is sort of handy, but in my case I am also selecting boundaries that are not in a particular plane, so this does not solve my problem.
I tried to use 'Supress Domains' before, but upon changing to the 'Free mesher' the surpressed domains are "unsurpressed" and everything is shown again. Interestingly, using the 'Hide Selected Object' icon (see Ivar's jpg) did help a lot, as by using this icon to hide domains allowed me to select the desired boundaries (which are the internal boundaries still shown after one domain was hidden). It's not very convenient but it should do until version 4 is released.
Reading the Beginners guide did also help to learn about 'Confirming Selections' - which is also very handy.
Thanks a lot,
Kurt