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naveen March 23, 2006 01:38

problem related to mesh
 
hi this is naveen ,i have problem while doing the surface mesh to my object in a domain.my object is cylinder which is having 16 mm dia,0.000625 depth.it is located in a domain which is having the 960mm lenght and 640 mm hight. i am get errors while i am doing the surface mesh to the cyliderical object.i dnt know where i gave good values for default body spacing and for the face spacing and also for the infaltion. this are the error mentioned below:

Problem.1:

surface mesh has small internal angles. Result: This may result in a poor quality volume mesh.

Cause: Mesh spacing does not adequately resolve

CAD face or feature of CAD face. Action: Reduce mesh spacing in region of face.

Cause: Highly distorted parameterization of face. Action: Examine face and Re-Draw in CAD system.

Cause: You are using the Delaunay surface mesher and

part of the boundary of the problem surface has

a length scale on it that is much less, i.e. more

than an order of magnitude less, than the requested

length scale in the interior. Action: Try increasing the length scale on the overly

fine boundary or reducing the length scale in

the interior of the face. Also check that the

length scales in the interior of the face are not

being limited by a minimum edge length.

Cause: CAD edges almost tangent at CAD vertex. Action: Examine face and Re-Draw in CAD system.

The worst angle is 3.647D+00 degrees.

F3 coordinates: [ 7.5757E+00, -2.5378E+00, -6.2500E-03]

[ 7.5943E+00, -2.5153E+00, -6.2500E-03]

[ 7.5962E+00, -2.5095E+00, -6.2500E-03]

Problem:2:

Boundary edge does not exit face (Subr: cutlist). Result: Failure of surface mesher for this CAD face.

Cause: Mesh spacing does not adequately resolve CAD face

and results in self-intersecting boundary edges. Action: Reduce mesh spacing in region of face.

Cause: Parameterization of faces poor near singular points. Action: Try rebuilding the model to improve the

parameterization of this face.

so, tell me does any one i having idea about this problem.thanks,,,,


TB March 23, 2006 03:30

Re: problem related to mesh
 
For small angle problem, check the location of those problematic cells and then try to simplify your geometry around that area if possible. Get rid of surfaces with sharp edges.

For complicated geometry, use ICEM instead of CFX-mesher. What meshing tool are you using anyway?

naveen March 23, 2006 13:19

Re: problem related to mesh
 
thanks for the response , as i understood from you mail that the cylidrical circle which is haviing sharpe edges not complete circle, when i zoom it it shows something like that .for that circle i am using surface mesh.it was freezed in the domain. if it the reason,may´be i need to create the cylinder in CAD in order to get smooth the circle?

Richard March 25, 2006 08:47

Re: problem related to mesh
 
just a gentle reminder: if u are drawing the geo in an external cad software, u might need a even finer mesh for geo created in cfx. this is from personal experience


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