3D pipe o-grid GAMBIT
 

Hi,

i've try to make o-grid circular mesh on pipe 3-d. tried many times since yesterday didn't work.


now my idea, i make a face circle, and i have to split it into 8 pieces each @45°

how to split the circle face into 8 pieces faces @45°

how to do this on gambit ??

many thanks for help.
salzferkel

post a sketch of what you want

thanks max.

here the pic

regards

on your picture you have a coax cylinder (one small cylinder hollow)
Attachment 8518

hi max,

yeahhh this is my problem.

i can make the one that in the middle hollow. i creat the mapped mesh on the outer face of cylinder, then submapped mesh on the face, circle ( inlet ) afterthat then i say to gambit should make the whole pipe (volume meshing) .. i've got as attached. it looks not good as in the hollow

should i just leave it hollow for the computation ? because it should a full cylinder.

attached the one i did now

Instead of a circle in the middle, create a square, then split the surface which surrounds the square into 4 sub-surfaces (see picture).
Mesh the square first, then the other.
Attachment 8520

alright, how can i split the surface that surrounds the square into 4 sub-surfaces in gambit ?

thanks

create your vertex on the circle (with split edge for instance)
Then split surface with vertex: select one square corner and the appropriate vertex on the circle (it will split the surface with a line)
etc..

thanks a lot max.

i've splitted the surface and the square as order.

now i try to mesh, if i starting from the surface square as map, then the surface circle ( see attached) gambit offer only pave option. i mean, if i switch to map mesh, it didn't work.

if i starting meshing from surface of the contour of the cylinder, then the the (inlet ) splitted surface (circle and square)
i got the mesh not as circular. see attached pic 2.

im sorry, im quite new with gambit.

thanks lot :)

split also volumes:
split full pipe, with square-section-pipe
Then split volume surrounding the square-section-pipe with planes which will generate 4 sub-volumes.

thanks lot max.

but i got problem with splitting the volumen. it didint work. gambit said, it has a non volumen geometry. i try to comprehend.

i created 4 vertex alongside surface circle. then split surface with the square.

i found when i splitted the surface circle with the square with vertices ---> virtuell. (see attached) and the face change to non geometrical face. it means virtuelle surface ?? not real geometry

i dont know what i did wrong with splitting.

Hi Max...

finally i find the way!

well i get your idea to split the surface. but seems when i the circle edge splitted , seems the circle has got distorsion ,and the end of the vertex to another part of the surface didnt joint together.

now i didnt create the square in the middle. i just make the circle surface. then spitted into 4 quadrant.

when i click the mesh on the face, it marked a pizza slice orthogonal.

i've got not much experience, but i think the meshing now quiet good for computing. see attached.
what do you think ? is that enough to a good circular meshing for computing ?

thanks lot for helping.

:)

finally i know how to split the surface. so now i made the version square with circle. (see attached) it also works.

many thanks Max!

extrude in Gambit
 

can any body tell me :
how can i extrude airfoil in Z dir by using GAMBIT?

tanx
___________
rasoul

sweep surfaces, and choose vector option

There is no only one way to mesh a domain.
You can mesh with hexa, tetra, wedge, hybrid, coarse, fine, etc...

tanx max for your quick reply, i will try it ASAP, but would you tell me how can i see velocity or pressure contour for inside of the 3d geometry. on the othe hand i wanna eliminate or pale all bondaries to see what happen in it after run and see any contours. i dont want to use clip or slice or etc

tanx
___________
Rasoul

if you don't want to use clip, sweep etc... then there are path lines.

how to get path line!!!?

____________
Rasoul

tanx but i use OpenFOAM software not Fluent, how did it in OpenFOAM??

_______
Rasoul

For post processing you need paraFoam (OpenFOAM), or you can export your results in VTK format and then open them with Paraview
In paraview use Stream Tracer icon

tnx, i used stream tracer icon in the paraview postProcessing, but it is shown stram line at 2D or face, but how to visualize stram line in 3D ? it is right my question

I am pretty sure you load stream tracer from a boundary (ie: surface)
open the result from your internal domain and once again stream tracer

i got it, tnx dear max, i used stram tracer and set point Source in the Seed Type :)