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cannot select an edge to become an outlet boundary

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Hi!
After struggling for quite a while with 4.2a, I haven't been able to enable one edge to become an outlet. What I did was to construct two objects: the first one is a sequence of lines, which I then made to become a single curve, which in turn I converted into a solid. Then I built a rectangle, which is supposed to embed the first flat, 2D figure. The first figure has an inlet, which was easy to make, just selecting the proper boundary, and that was it. The outlet, no matter how many times I selected that boundary, won't be added to the right blank place, so that I can declare the outlet properties of it. I gave a look, and it happens that most edges (or flat boundaries) are walls. I tried to build the two objects in several ways, and I still haven't figured out how to make them, so that I can take this boundary as an outlet.

This is a matter of some urgency, so please, please, if you have a clear idea of what I need, do write it down. Or even if you only have a hint, but has some algorithmic clarity. I am including the geometry

Yours

Arturo


2 Replies Last Post 21 mai 2013, 09:59 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 4 déc. 2012, 16:03 UTC−5
Hi

an outlet is an external boundary, that's why you cannot define it n an internal boundary. Just as you cannot define the rest of the nozzle structure as any "wall", but you can define the sides as an "internal wall", then leave out the top nozzle and you have an "outlet from the small domain into the large one. Still you need an outlet somewhere else you will fill the large domain with higher and higher pressure

By the way internal walls might be a 4.3a feature, not sure when it arrived ;)

--
Good luck
Ivar
Hi an outlet is an external boundary, that's why you cannot define it n an internal boundary. Just as you cannot define the rest of the nozzle structure as any "wall", but you can define the sides as an "internal wall", then leave out the top nozzle and you have an "outlet from the small domain into the large one. Still you need an outlet somewhere else you will fill the large domain with higher and higher pressure By the way internal walls might be a 4.3a feature, not sure when it arrived ;) -- Good luck Ivar

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Posted: 1 decade ago 21 mai 2013, 09:59 UTC−4
Thank you!
it worked marvelously (v 3.5a)
Thank you! it worked marvelously (v 3.5a)

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