[ulalala]

While creating hex mesh, i am having problem with surfaces of high radius of curvature. eg: a part of sphere with very large dia.

Please help...

[jeevankumarb]

if you can post the images then it would be easier to understand.

[ulalala]

here is the snap of the curved portion

[PSYMN]

I am not sure what problem you are having with this geometry (usually, people want to see your first attempt so they can see where you got stuck), but I can tell you how to deal with it... Assuming you want flow thru this (different instructions apply to flow around this shape).

First, imagine that it is just a tube with a step down at the end. It may even help to create an ISO curve half way thru that curved portion that forms a concentric circle with your tube... We would pretend that was the step down crease.

Here are the basic steps. Assume the pipe axis is Z.

1) Initialize block around the geometry.

2) Create an Ogrid. Select the single block and the faces at the pipe ends. Set the Ogrid scale from 1 to 2 (this should make it come in 2/3rds of the way to the middle). Apply. The center HGRID of the OGRID should be fully within the small end of the pipe. If not, rescale the Ogrid until it is.

3) Create a single Split Across Z where the curved region meets the outer diameter.

4) Create a Single Split across the Ogrid direction to capture the small end of the pipe.

(We are now done all the splitting.)

5) Delete the 4 outermost Ogrid Blocks around (outside) the smaller portion of the pipe.

6) Associate... The big end of the pipe should be obvious... So is the small end. The outer part of the sharp step should be pretty clear also. The inside corner of the step should associate to the iso curve along the curved surface.

7) Set sizes, etc. and done.

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