|
[Sponsors] |
June 9, 2003, 18:25 |
How do you think CFX-Build?
|
#1 |
Guest
Posts: n/a
|
CFX-Build almost kill me the desire to be an engineer. I tried to build a drill hole with stell case in it. The hole is 1000m long and the diameter is 9''. In order to save computer resource, I tried to build a cylinder then cut it into quaters. But I got error message when I try to mesh it. Anybody know better mthod to build a model.
Thanks! |
|
June 9, 2003, 18:32 |
Re: How do you think CFX-Build?
|
#2 |
Guest
Posts: n/a
|
Hi David,
What error message did you get? Glenn |
|
June 9, 2003, 18:35 |
Re: How do you think CFX-Build?
|
#3 |
Guest
Posts: n/a
|
Hi, Glenn,
Thank you for your prompt response. The error message is as follows: Error: ------ Problem: Topology error detected in CAD model. CAD edge referenced 4 times by faces. Result: Model invalid for meshing. Cause: Invalid model. Action: Please refer to the user documentation "Using CFX-Build, Section 5 Meshing" for topological limitations, and modify the model accordingly. Solid 3.3.3 Thanks |
|
June 10, 2003, 03:50 |
Re: How do you think CFX-Build?
|
#4 |
Guest
Posts: n/a
|
You have big diference in dimensions (1000m to 9"). Try to use hexa cells in some other mesh package or in CFX-Build if it is possible.
REgards, gg |
|
June 10, 2003, 18:23 |
Re: How do you think CFX-Build?
|
#5 |
Guest
Posts: n/a
|
Hi David,
As gg said, your hole is very long and thin so the default tetrahedral mesh will not be very good. You should create a hexahedral mesh of the geometry - if you are using CFX 5.6 you can switch that on by changing the meshing mode. It is covered by the documentation. If you are still on CFX 5.5.1, it is a lot tricker but still possible to make a hexahedral mesh. There have been postings about doing this on this forum previously. Glenn |
|
June 11, 2003, 11:29 |
Re: How do you think CFX-Build?
|
#6 |
Guest
Posts: n/a
|
Hi David!, you have to separate the case in diferents sections (1000m is too large!), at the same time you need to locate de hole in a ring which belong to the tube. I had the same trouble !.
Take Care Carola |
|
June 11, 2003, 21:10 |
Re: How do you think CFX-Build?
|
#7 |
Guest
Posts: n/a
|
I really appreciate your help.
I tried to use Patran (in CFX 5.6) to descretize the geometry. Finally I got four domains in the problem. This time errors comed up in Solver. It says: </n> ERROR #004100018 has occurred in subroutine INMES. | Fatal overflow in linear solver. </n> I know the aspect ratio for the element is 0.05/10=0.005. Can anybody tell me whether large aspect ratio cause overflow? Thanks! David |
|
June 12, 2003, 12:38 |
Re: How do you think CFX-Build?
|
#8 |
Guest
Posts: n/a
|
Not likely, as this is not that large an aspect ratio. Check your boundary conditions and verify that the mesh is in the right units (check dimensions in Post).
Robin |
|
June 13, 2003, 16:32 |
Re: How do you think CFX-Build?
|
#9 |
Guest
Posts: n/a
|
Hi,Carola,
Thank you! Did you mean that I can divide the whole geometry along the center of the drill hole into several sections, for example, every 100 m/section. Regards! David |
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
heat generation in CFX | Ema | CFX | 4 | August 7, 2009 05:39 |
Electronics Enclosure Analysis with CFX | Simulation Engineer | CFX | 1 | April 22, 2009 11:08 |
Importing solutions in CFX. | Alphonso | CFX | 1 | August 1, 2008 14:01 |
Fluent Vs CFX, density and pressure | Omer | CFX | 9 | June 28, 2007 04:13 |
CFX 4.4 installation problem | Pandu Sattvika | CFX | 1 | December 1, 2001 04:07 |