[Ananthakrishnan]

Hi everybody,
I am trying to mesh a combustion chamber (using unstructured mesh). I have attached the geometry file and the mesh i created for the combustion chamber of a gas turbine engine in the dropbox link below. Can someone please have a look and let me know whether its good or not!!! i will be really thankful.

https://www.dropbox.com/sh/jes8accs86nu0ai/QP3arwI26S

As i am new to unstructured meshing i dont know all the facilities available in ICEM.. If possible, please give some alternate ideas about how to proceed with this. I am trying only unstructured mesh as I think structured mesh would be very difficult for this geometry..

Thank you very much

[diamondx]

hey there, you mesh is not smoothed. possibly interrupted because of holes in the geometry, have you done build topology ??? i can assist you meshing this...

[diamondx]

let me know if you still need help with it

[Ananthakrishnan]

hi,
thanks a lot for your reply. I would be really thankful if you can continue assisting me with this..i did build topology while creating the "body (fluid)"..

After few trials, i was later able to get hold of the meshing procedure. https://www.dropbox.com/sh/jes8accs86nu0ai/QP3arwI26SI have also sent the dropbox link directly to you( i already had your email id). This is the procedure which i followed
1.build topology
2.create parts with whatever things you need to control the mesh separately
3.give proper values for element size in part mesh setup
4.create surface mesh using triangular elements (earlier link contained tetra. I feel triangular elements can follow the geometry better).
5.create volume mesh without using the surface mesh (if i create vol mesh using the surface mesh, the vol mesh goes outside the domain, i dont know why!!!!)

current problems...
1.not all the holes follow my part mesh setup size (two holes are meshed with bigger elements which do not follow the curved geometry)

Doubts
1.what is the best manner to create the volume mesh. is the one which i explained above sufficient or are there better ways to do it!!!
2.should i improve the surface mesh as much as possible before proceeding to volume mesh (i my case its not useful because, if i use the surface mesh to create vol mesh it goes outside)

Thank you very much!!

[diamondx]

the steps you followed are good.
as a start, directly compute the volume mesh (octree method)
see if your curves node distribution is respected.
then generate your delaunay, you don't need to erase anything...

[diamondx]

in the project that you shared, i don't see the curves in a special part... you must have missed some of them, that is why it does not respect them.

[Ananthakrishnan]

Hi,
thanks for the help..i added the rest of the parts which were missing and the mesh was better.
i then tried delauney mesh but the mesh becomes something like in the picture attached..It was good with octree method though..

[diamondx]

you can'T generate a delaunay without a surface mesh. you have to generate an octree mesh , then switch to delaunay.

[Ananthakrishnan]

Yes i did that
1.create volume mesh directly using octree.
2.create volume mesh again through quick delauney with volume part name as "inherited" and input as "existing mesh"

thanks

[diamondx]

ananthakrishnan,
Are you injecting kerosene in your chamber ??

[Ananthakrishnan]

yes.
.......

[diamondx]

have you started yet ???

[Ananthakrishnan]

yes, i have but i am still working on the mesh simultaneously. I want to improve it

[gurkan]

hi guys, i have a problem with same situaton and I am already newbie for meshing a volume. so could you please help me to prepare meshing a annular combustion chamber, do you have a video or something like tutorial to solve my problem. or could you please how can i start and what procedure do i have to follow? i am preciate for your help. also i thought i have to make 3d mesh for that situation and if i explain my problem a little bit;
i will use fluent to solve flow characteristic inside the flametube and annular tube. but first i have to mesh my combustion chamber volume.
i have already flow volume, i mean i divide my combustion chamber volume by two part those are flametube volume and outside of the combustion chamber which is annular tube.
please help me, at least for making mesh to this problem.