hydrocyclone Mesh Quality.
 

https://docs.google.com/open?id=0B1F...EplUG4zVFVaOUk

Hi Everyone,

I’m working on the meshing of hydrocyclone with gambit. I finished the mesh but would if anyone can advise me if my work in correct or these is some lacks?
I went to mesh exam and set to range from 0.9 to 1, there are 5 grids appeared in face 14. Should I change the geometry by lifting this face or I can use sweep face in the z direction by 1 unit.
For all volumes I set the aspect ratio by 1, should I change it to 0.45?
Note: this work is a two phase flow (water contains sand particles). I meshed all faces by Hybird/Tgrid.

please see attached file in the link below on google documents:
https://docs.google.com/open?id=0B1F...0hSR0xKdGpPbW8


Highly appreciate any assistance
Thanks for Mr. mAx for assisting me.

Osamah Al-Hashimi

your link doesn t work

Here the link sir ... it is the same file i sent you before and you checked it ...
I just like to view the procedure for solving the two problems you spcificed.
is this procedure oK?
https://docs.google.com/open?id=0B1F...0hSR0xKdGpPbW8

REGADING the aspcet ratio, Please see attached pic when i change the Aspect Ratio from 1 to 0.45 ... can i keep the Aspect ration by 1?

Thank you

Attachment 17328

Again your problem are only on edge 5, edge 9 end edge 12
You can fix your both first issues by giving more nodes on edge 5 and edge 9
Edge 12 issue can be fixed if you sweep face 14 in z-direction (small vector). Then sharp angle at vertex 12 wil disppear if you suppress edge 12 (by merging surface 8 with new surface from sweep)
Attachment 17349

Many Thanks Freind
These problems appears when I try to merge face 8 with the new face from the sweep (face 20)
Error: Tried to merge faces face 8 and another from the list that are not connected.
I tried face 14 with 20 … same error appeared.
I tried face 8 & 14 & 19& 20 … this error appeared:
Error: tried to merge faces face 8 and face 19 with different upper topology or with nonmanifold neighbors (share the common boundary with another face).

Attachment 17356

Attachment 17357

Attachment 17358

before you merge both surfaces, you need of course to merge both volumes

Thank you very much
I merged the two volumes … a v_voulme.6 created … mesh is done but is it ok?
Attachment 17359

Attachment 17360

examine mesh and check quality (skewness < 0.9 should be ok for tetra mesh)

it is 0.74 ... Please see attached picture.
Is the vertual volume a problem?
Many thanks sir for your time and for advicing me ... thank you very much

Attachment 17361

should i change the vertual volume to real? can i say that i have accepted quality mesh to work on a two phase flow in fluent.
many thanks many times

virtual isn t a problem
you can go and solve

Thank you verrrrrrrrrrrrrrrry much ... god save youuu.

Hi, i made a new geometry ... and re meshed it in Gambit
In Fluent i made a <report quality> for both meshes , i got this results:

Mesh Quality (for the geomety you assisted me in):

Mesh Quality:
Applying quality criteria for tetrahedra/mixed cells.
Maximum cell squish = 7.24566e-001
Maximum cell skewness = 9.54236e-001
Maximum aspect ratio = 1.65974e+001

***************************************

Mesh Quality for the geometry i made (the new one):
Applying quality criteria for tetrahedra/mixed cells.
Maximum cell squish = 7.24566e-001
Maximum cell skewness = 9.54236e-001
Maximum aspect ratio = 1.65974e+001


is there a problem in the Maximum cell skewness of the second geometry?

Many thanks freind for your continouse assistance ...

i have enhanced the mesh of the new geometery, the result is:

Mesh Quality:
Applying quality criteria for tetrahedra/mixed cells.
Maximum cell squish = 7.24566e-001
Maximum cell skewness = 7.92745e-001
Maximum aspect ratio = 1.65974e+001


I think it is much better ... Many thanks mAx :D

Quality should be ok. Since you don't get a "Grid Check Failed" you can go and solve.