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-   -   [GAMBIT] About creating complex geometry (https://www.cfd-online.com/Forums/ansys-meshing/105475-about-creating-complex-geometry.html)

cdoferreira July 31, 2012 19:49

About creating complex geometry
 
I am new in the CFD field, so this means that I have only worked with and developed simple geometries in Gambit to work along with FLUENT. The most complex geometry I've created was a 3D hydrocyclone. This made me wonder if there is another program that makes the creation of more complex geometry possible, or any program such as Autocad which can be used along with Gambit to make this possible.

Thanks for the further replies!

Marion August 1, 2012 03:04

Do you mean the CAD geometry?
Then it's a CAD software you need. I don't know the recent versions of Autocad, but a few years ago they weren't that good with 3D geometries. I use solidwors and it is very convenient for 3D parts, at the same time it is easy to use and much less complicated than Catia for example.
You can also try Design Modeller if you have workbench. It's not a proper CAD package but it is better at geometry definition than Gambit I think.
Marion.

cdoferreira August 1, 2012 09:59

So is Gambit able to import CAD geometries from any CAD extension program so I can mesh them later?

Marion August 1, 2012 10:55

I do not know if gambit is able to import geometry from ANY CAD software, I use parasolids (.x_t) and it works fine.
If you want to know which formats gambit can open, I suggest that you start Gambit and click on File / import --> then you will see what you can import.
There is a tutorial about importing IGES geometry: 5. importing and cleaning up sedan geometry.
Marion.

-mAx- August 2, 2012 00:45

Step import from ProE works good for me

cdoferreira August 6, 2012 01:05

Thanks a lot! I'll try SolidWorks and ProE and later post my feedback! Gambit can import a lot of files, as I expected. There is CAD import from Gambit and also Parasolid extension files (.x_t, etc).

Thanks!

hhh September 13, 2012 09:30

Gambit Geomentry Problem
 
3 Attachment(s)
Dear friends,
i am using gambit to draw my 3D wing,i create outer domain, the problem i face is my wing face & domain face are intersect i want to stick my wing face in one of the domain face, For that how i tilt either my wing face or my plane(face) to make a cantilever beam, please see my attached wing( in that red color shows wing face1, I want to stick face 1 to face2 like cantilever beam, then i want subtract my face 2 to face 1, please see the attached various position of image, please help me

-mAx- September 13, 2012 09:40

If you stitch your wing then you get a volume.
Then you can easily split your wing-volume with your face2

hhh September 14, 2012 02:52

Gambit Geomentry Problem
 
3 Attachment(s)
thanks max, for your response, what i am asking is , I already make wing as volume, that is volume1, and outer domain volume 2, but my problem is i want to attach wing face 1 to domain face2 like cantilever beam, the problem is wing face 1(ie red color) is not parallel to axis Gx its slightly tilted.

if you consider volume all faces are parallel to according to Gx,Gy,Gz axis, here wing face 1(chord length) is not parallel to Gx axis it is tilted, if its parallel then its easy to attach wing face 1 to domain face 2, here the possibilities is either i can tilt( make parallel) my wing face 1 to Gx axis or i tilt my domain face 2, please see the attached my images.

-mAx- September 14, 2012 03:05

your wing volume is going out of your domain volume.
So if you want to comput the whole wing then you need to sweep a little bit your outer domain.
Now I don't get exactly what you want, Do you want your wing to be fully attached to face 2?
Then you need to sweep the wing-face1 in one directiion, and then split the new volume with domain face 2.
You could also rotate your outer domain, but I assume your fluid is entering normal to one of any face in current position, right?

hhh September 14, 2012 08:53

Gambit Geomentry Problem
 
thanks max

Do you want your wing to be fully attached to face 2?

whatever u understand is correct, thatis to attach my wing face1(shows red color) to attach domain face 2 ( finally wing looks like cantilever beam)

-mAx- September 14, 2012 08:57

Quote:

Originally Posted by -mAx- (Post 381744)
Then you need to sweep the wing-face1 in one direction, and then split the new volume with domain face 2.

http://aerojet.engr.ucdavis.edu/gamb...eom_volm_sweep

hhh September 15, 2012 03:25

Gambit Geomentry Problem
 
thanks a lot max for your kind response & help, i got it.

hhh September 15, 2012 08:37

Gambit Geomentry Problem
 
1 Attachment(s)
Dear max,

According to my problem, i am doing 3D wing analysis by using gambit & fluent software. i subtract my wing from outer domain, My velocity is 5m/s, area is 0.0102 sq m, length is 0.065 m, for my case it is steady, laminar, incompressible flow, i want to do analysis, in fluent i don't exactly which boundary condition i suitable, please see the attached image, in that i consider wing as wall, one face is velocity inlet& opposite face is pressure outlet, remaining faces i consider symmetry boundary condition is it correct for my problem,

For this problem what is exact domain size & boundary conditions, please help me.

Domain size
From velocity inlet to wing is (3x) remaining all are 6x , x is length.



-mAx- September 17, 2012 01:25

http://aerojet.engr.ucdavis.edu/flue.../tg/node36.htm

hhh September 17, 2012 02:13

2 Attachment(s)
Dear max, thanks

According to my problem,i consider wing as wall, one face is velocity inlet& opposite face is pressure outlet, remaining faces i consider symmetry boundary condition is it correct for my problem, please let me give your suggestion and domain size ,please see the attached image

-mAx- September 17, 2012 02:29

for me it is not correct, but I am not familiar with such calculations
I let other members to discuss over this topic


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