Help a novice to solve a simple liquid-in-solid problem

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mspock
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Joined: 14 Jun 2012, 09:05
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Help a novice to solve a simple liquid-in-solid problem

Post by mspock »

Reporting here my case, that I had posted in Bugs section for my mistake.

Hi everybody.
I'm totally new to Elmer at the moment. It's been only for a few days that I'm trying to understand the basis.
I'm using GID as mesher but maybe I'm driving to another one in the future.
I'm using ThinkDesign as 3d environment.

Project: I'd like to study the thermal flow in a solid cooled by a water pipe.

what I do:
- export in stp, stl, igs formats. For example, the solids I export are 1) a cube with an hole 2) a cylinder representing water. The cylinder is exactly matching the hole in the cube.
- import in GID the solids: cube in layer 0 and tube in layer 1 (although I suppose Gid has a bug here, importing only to layer 1 so one has to move objects to other layers in order to prevent them to be overwritten).
- adjust the surfaces and volumes to make 2 separate solids: cube with hole and tube the external surface of the tube and the hole surface should now collapse or not? Should I mantain one surface only?
- meshing: 3d or 2d? In the curved pipe example, 2d mesh is used.
- problem type: elmer -> set data, materials, volumes. My goal is to assign a material (ie steel) to body and another one (ie water) to the cooling liquid. Thanks to different layer I succeed to assign them.
- problem type: elmer -> set data, costraints, surfaces: I assign costraints according my wanted boundaries: 1) steel body (all surfaces but the inner hole one) 2) cube inner hole surface 3) one base of the cilynder 4) the other base surface 5) the lateral cilynder surface : total of 5 costraints. Is it correct?
- save project and calculate
- importing in Elmer: open mesh--> select folder of previoously calculated Gid problem
- elmer crashes. Either does crash importing the 2 solids having a common surface, or it does import only one solid, even if I exported both by GID.

Have you guys some advice/tutorials/step by step guide to import a geometry consisting of a solid with a hole in which i can make a liquid flow to refrigerate it?
I can't just understand where am I wrong !!

Thank you so much.


I'm attaching my geometries. I can't successfully import in elmer the meshed solids with the right boundaries to distinguish the water from the solid and to input the boundaries equations (heat transfer from solid to water and vice-versa, water flow and so on..)
Could anyone try to mesh this simple geometry and import it in Elmer with the correct boundaries? I'd like to simulate a case like an elmer's sample curved_pipe.grid but i'm unable to manage it (of course i know elmer does support only a solid at a time, that's why I'm working with GID or SALOME (in Salome I can't partition them either 'cause it crashes).
PLEASE HELP ME! thanks !!!!!
Attachments
2 solids.zip
The plate in which I want to make the liquid flow, and the liquid (cilynder)
(7.18 KiB) Downloaded 379 times
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