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pmadduri89 March 1, 2013 13:42

Meshing problem
 
I have a irregular shape body thats used to define the fluid region in my problem. I tried using prism layer, surface mesh and trimmer combination for my mesh. The mesh is not good at all. I am not sure what to use.

Could anyone suggest some better combination for this? Any kind of suggestions are highly appreciated.

PS: I have attached the link of the body that I have used and the meshed scene also.



http://www.facebook.com/media/set/?s...type=3&theater

grad@itu March 1, 2013 14:15

Hi,

If you share more detailed photos with us, we can say more efficiently things..
First look, your prism layer thicknes is thick, you can reduce the prism layer thickness.. think about region around the circle..
And you can change minimum surface size for trimmer mesh, you can reduce minimum surface size. and generally you can adjust x min. surf. size against 2x max. surf. size combination.

You can use polyhedral mesh as well..

pmadduri89 March 1, 2013 16:02

Thank you for the quick responce....i find my resh a little better when I reduce the prism layer thickness and surface size...but I still find a little distortion at the start of the branches...

http://www.facebook.com/media/set/?s...type=3&theater

I am not pretty sure of why is this happening....i tried a few things like "create alligned mesh" and "create compatale mesh"..but no change is happening

grad@itu March 1, 2013 16:11

actually it isnt distortion, these are tetras and tetras have to be form in this geometri, at least wedge mesh..
but you can reduce a litte more min. surf. size value and tets will be form near around the central circle..

why are you try poly?

and if you want still trimmer, you have to some adjustment over the size or other specs..
for example to mesh the circle geometry you can add the "generalized cylinder mesh" technique..

or may be you can do some path adjustments by using feature curves (defining feature curve for example middle of the arms through the arms lenght)..

you can think something like that..

finally, you have to check, cell face quality and cell skewness values if these are acceptable, you dont think the visual situation;)

pmadduri89 March 13, 2013 20:21

Thanks Grad@ITU for your help. I am kinda getting a hold over things now. I see a the results kidna better.

I had another question. Presty basic one though. What are the inlet conditions and outlet conditions for the following cases:

1. Forced convection
2. Micro jet cooling

I mean....is it like flow split outlet at the outlet and velocity inlet at the inlet for the forced convection??

If it is so, does that mean having a pressure outlet at the outlet instead of flow split would give me the Jet cooling condition?

I have a pipe and I am trying to cool it by passing water inside it. The walls are being heated with a constant heat flux.
Hope you help me through.
-Prasanth

pmadduri89 March 13, 2013 20:26

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