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zaidhasany February 25, 2011 02:01

Query regarding grid generation of multi scale geometry
i encounterd with a problem related to the grid generation in GRIDGEN, my geometry dimension scale vary with 10e4, hence it has beome quite difficult to model properly, basically i have to make grid in between two spherical geometries, radii are of the order of 5 cm and the clearance is 0.001 cm.
can any one guide me!!

rmatus February 25, 2011 10:38

What kind of problems are you seeing?

That range of geometric scales should not be difficult for Gridgen to handle. What are the symptoms of your problem?


zaidhasany March 1, 2011 05:17

thanks a lot for your reply, when i created the connectors on the data base (igs format) due to LSQ issue or else, connectors overlap each other or come closer which would definitely make problem to make the domain and block.

rmatus March 1, 2011 10:15

Try Double Precision Graphics?
Hi Zaid:

Connectors created on a database in Gridgen will be directly on the database curve or surface, so if the database entities are not crossing the grid should not cross.

Once thing that may cause the connectors to appear to cross when dealing with very small scales is the graphics resolution. Gridgen does all its internal calculations and storage in double precision, but the display graphics are only single precision by default. As a result, sometimes when you are zoomed in to a very small area the grid might not be displayed at its precise location.

You can change this default behavior in the Display Commands menu. Choose FramBuf, and then select double precision graphics.

Hope this helps,

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