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star-user April 6, 2008 07:13

subsurface failed
 
hi all,

I want to generate a nice subsurface for my complex duct model. the subsurface has failed in some regions of my model where the angle between surface is lower ( i guess). but the surface elements are of good quality.

it results in zero thickness subsurface. so it results in poor quality tetra. i would like to avoid that. is there any advanced options available in proam.

I only want to use Method 8 since Method 4 fails in prevailing subsurface thickness everywhere.

If anybody knows, please letme know. thanks

please also have a look at the attached image.

http://i291.photobucket.com/albums/l...ubsurface1.jpg


Jim April 6, 2008 08:39

Re: subsurface failed
 
There is an advanced option you can use to change the boundary marching angle, this changes the angle at which the subsurface is "pinched" into a corner where one surface has prism layers and the other doesn't. In the advanced subsurface box at the bottom put -march-grow-boundary=xxx where xxx is an angle, I can't remember what the default is so you best contact the support guys at cd but that should do the job for you.

Donald April 6, 2008 11:05

Re: subsurface failed
 
it is documented in the advanced meshing: CT (compatibility tolerance)

star-user April 7, 2008 05:25

Re: subsurface failed
 
hello Jim and Donald,

the march-grow-boundary parameter works good.

thanks for your kindly help.

user1 April 9, 2008 05:58

Re: subsurface failed
 
Hello Jim, Donald

Now i have a subsurface issue which is much like as a one i posted.

the subsurface is going to the sharp corner and bouncing back, actually i want to avoid that. i gone through the userguide, but no much help over there.

the outer line is surface, and inner line is subsurface.

the CT value Donald told will work only with Subsurface "Method=4", it doesn't wrk with Method=8 (which is robust).

so is there any other parameter, which controls this.?

Please look at the image.

Thanks

http://i291.photobucket.com/albums/l...ubsurface2.jpg


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