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Ali November 1, 2008 03:21

Hi I need urgent help any body can help me? This is my problem: When i add my obstacle in F3D 8.2 the shape of obstacle will be deformed.I dont know what should i do? My obstacle is ogee crest and created in Catia and is stl file.


Farokh November 2, 2008 00:10

Salam Ali.
Where are you from, Ali?

Ali November 2, 2008 05:22

Re: Salam Ali.
Salam Farokh I come from Iran. Now i am post graduate student of water engineering.Now i am in Zahedan.Do you khow where is Zahedan?Can you help me?Where are you from too?

Andreas November 3, 2008 05:11

Re: Important
1) Is your mesh resolution high enough to resolve your obstacle? Try to increase the values in Meshing_Geometry->Mesh. Does this help?

2) Maybe something is wrong with your STL: holes, non-connected edges. This can happen, if the construction is not based on solids, but on surfaces. To work properly, the stl export filters usually require the construction of a correct solid body. If not, it can happen that faces are not connected. To a certain degree, Flow3D can deal with this errors. But sometimes the conversion problems spoil too much. There are free third party codes to check the integrity of your STLs.

CK November 4, 2008 05:33

Re: Important
Consider to used latest version of v9.3. it should resolve your problem.

Stefano November 4, 2008 09:48

Re: Salam Ali.
Hello Ali, what do you mean by "deformed"?

If you see your object like "smoothed" and you "loose" some of the corners of your geometry, than probably it is a problem of mesh resolution.

If you see your object quite much different, with holes where they shouldn't, and "scattered" surfaces inside, than probably the .stl file is to be fixed. (in this case you can try to use admesh to fix it)

Ali November 5, 2008 05:42

Re: Salam Ali.
Salam Farokh My obstecle is ogee crest.I draw it catia and save it in stl file.ogee is one kind of spillway crest.My problem appear when i add this stl file as new obstacle in geometry panel.This time my ogee shape transform to rectangular shape. You didn't tell me where are you from?Can you help me?I am working with F3D 8.2

khyli mamnon

Stefano November 5, 2008 11:29

Re: Salam Ali.
Ali, it's hard to understand better where the problem comes from. Usually differences between the original shape and the post-processed one can come or from a bad .stl (try to use admesh to check it) or a large cell size. F3D 8.2 is also a very old version, you should think to purchase an upgrade to the newest one... (many problems will disappear and I'm sure you'll can run quite faster simulations!) I'm from Italy.

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