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Jenny December 22, 2007 10:44

Meshing very thin blade tip
 
Hi,

I am hoping someone may be able to suggest a solution I have to meshing the tip of a fan blade. I have to use the CAD model as is and can't modify it, however the blade trailing edge tapers off to a very fine point. I have uploaded a screen shot here -

http://www.flickr.com/photos/2207547...hoto2128997366

Apart from making the edge face very small with tiny minimum edge spacing e.g 0.001mm, does anyone have suggestions how I can an awful geometry like this, under these conditions.

Thanks in advance for any help anyone can give.

Jenny

Glenn Horrocks December 25, 2007 06:14

Re: Meshing very thin blade tip
 
Hi,

Airfoils are best meshed with a structured hex mesh. Then there is no problem at blade tips. You will need ICEM hexa in this case.

If you still wish to use the default CFX mesher then You cna either use ICEM or WB, they both can do it but it is tricky to get a good mesh. The best way I have found is to get a thin surface to come out from the sharp edge and place inflation layers either side of the thin surface. Of course in CFX-Pre you do not define the surface as a thin surface.

Glenn Horrocks

Jenny December 25, 2007 08:34

Re: Meshing very thin blade tip
 
Hi Glenn,

Thanks for your reply. Unfortunately the blade can't be meshed with a structured hex mesh due to complexity of curvature, as the blade is made up of quite a few different aerofoil profiles.

I'll look into thin surface idea and see if I can get this to work. Thank you for your suggestion.

Best wishes, Jenny

pankaj December 27, 2007 07:15

Re: Meshing very thin blade tip
 
Hi Jenny!

I think hex is possible here. To caught curvature u can have points on curves and by splitting your edges you can associate vertices to those points.Its quite difficult but not impossible.

Hope you can do it.

Pratap Kumar DVS January 2, 2008 07:14

Re: Meshing very thin blade tip
 
Yes i will agree with pankaj in this, Hexa mesh is possible for this type of curvatures in Ansys ICEM CFD, I have done similar type of blades in Icem CFD. But it needs more patience to do... Even i have done the meshing in microns gap .... in ICEM CFD.. Any further help ontact me through mail...

Thanks & regards, Pratap Kumar DVS.

jaber November 9, 2010 14:09

ICEM HEXA to CFX-PRE mesh export pb
 
Quote:

Originally Posted by Pratap Kumar DVS
;85160
Yes i will agree with pankaj in this, Hexa mesh is possible for this type of curvatures in Ansys ICEM CFD, I have done similar type of blades in Icem CFD. But it needs more patience to do... Even i have done the meshing in microns gap .... in ICEM CFD.. Any further help ontact me through mail...

Thanks & regards, Pratap Kumar DVS.

sorry,my name is jaber,
i am using CFX 11 as simulating software and ICEM HEXA 11 as Mesher.
i have done a 2d extruded mesh (multiblock structured mesh).
but when importing mesh into cfx-pre: the inlet,outlet,wall1 and wall2 don't appear on outlet mesh tree.
any idea or suggestions will be wellcome.
thanks in advance.

Sujit June 27, 2014 08:07

Mesh Problems in Micron thickness
 
3 Attachment(s)
Hii I am also meshing one small thickness object of 15 microns .

Is it possible to scale up in thickness axis and hex mesh with blockings after that scale down the mesh and export??

my other question that i have one wedge like structure to mesh do anybody give an idea about blocking it.

wedge is upper part of my geometry.

Images are attached ..

please help me out ...

ghorrocks June 27, 2014 08:26

Try the geometry and meshing forums for tips on meshing.

Be aware that this geometry is likely to be difficult to converge due to the large range of length scales.


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