|
[Sponsors] |
June 25, 2013, 04:02 |
gambit mesh "T" tube
|
#1 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
hello everyone,
i am a beginner of gambit. now i am trying to creat a mesh on a "T" form tube. do you have some ideas pr suggestions about how to seperate the different parts? thank you |
|
June 25, 2013, 04:23 |
|
#2 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
you are not enforce to decompose your domain, execpt if you want a full hexa mesh
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 04:52 |
|
#3 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
i have used fluent to calculate, it showed that there were instability at the entrance of the small tube. so i have no choice to seperate the interval part to have a more precise part. but i always get a great number of mesh.
|
|
June 25, 2013, 04:58 |
|
#4 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
post pictures, and explain your boundary conditions
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 05:14 |
|
#5 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
Hello , this is the tube that i use,.
The boundry conditions are : turbulence with a velocity of 5m/s inlet. Flow rate weighting 0.5 ; 0.5 |
|
June 25, 2013, 05:18 |
|
#6 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
i don't knoz how to add pictures, to i make a link here. thank you
https://www.dropbox.com/s/s1ufa02vv9oka4k/0625.docx |
|
June 25, 2013, 05:19 |
|
#7 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
I don't see pictures
What kind of BC did you use for outlet?
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 05:19 |
|
#8 | |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
Quote:
__________________
In memory of my friend Hervé: CFD engineer & freerider |
||
June 25, 2013, 05:21 |
|
#9 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
please post picture with focus on your mesh, else we don't see anything.
Pleas post also picture of velocity and pressure distribution
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 05:48 |
|
#10 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
this is the document; https://www.dropbox.com/s/5oqvv81gvb...0question.docx
sorry for making you waiting so long, i am not used to the computer with the french keyboard that i use. |
|
June 25, 2013, 06:17 |
|
#11 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
ok can you display clother at the T junction, especially velocity distribution. Something sounds weird left to the T junction.
Regarding to the mesh, you seem to have splited your domain, right? Can you also list all the surfaces with their BC, I see lots of surfaces And finally when I see the the velocity distribution, I assume your inlet is the pipe with smaller diameter. But if it is exact, then the pressure distribution is wrong
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 07:05 |
|
#12 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
yes, you are right, i have splited the domaine.
the inlet is the left side of the larger pipe, the other side of it and the small pipe are the outlets. The diameter of the larger pipe is 20mm, that of the small one is 6 mm, and the lengh of all the three parts around the intersection is 500mm https://www.dropbox.com/s/c7o9q4nrku...question1.docx |
|
June 25, 2013, 07:13 |
|
#13 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
can you provide me your dbs file from Gambit? (delete the mesh for reducing file size)
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 07:24 |
|
#14 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
https://www.dropbox.com/s/nsfn9id1k1...lageRe10-5.dbs
here it is, there are some changes, i didn't save that version. |
|
June 25, 2013, 07:48 |
|
#15 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
ok, seems to be ok, but you don't have any surfaces in the BC.
I assume you fixed the problem. Other point: what are your dimensions m,mm,... ?
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 08:13 |
|
#16 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
the dimensions are mm. and in fact i am a beginer of fluent and gambit, i don't know which faces to add with BC
|
|
June 25, 2013, 08:21 |
|
#17 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
ok, did you scaled your domain in fluent?
Gambit doesn t have any dimension.
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 08:36 |
|
#18 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
ok, i find that i am totally fool, i thought the dimension was set by default as mm. i just searched the user's guide, it's set as Meter. however, i didn't scale the dimension
|
|
June 25, 2013, 08:42 |
|
#19 |
Super Moderator
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41 |
you have to scale your domain:
in your case, select mm, and then click on scale If you have a diameter of 20, Fluent will understand 20m If you scale it, Fluent will convert and undestand 20*1e-3 = 0.02m Once it is done, do a check mesh, to be sure that your mesh is ok. Then compute.
__________________
In memory of my friend Hervé: CFD engineer & freerider |
|
June 25, 2013, 08:45 |
|
#20 |
Member
steven
Join Date: Jun 2013
Posts: 41
Rep Power: 12 |
OK, thank you very much. i think i have to rebuild the mesh as the skewness exceeded 0.98
|
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Mesh motion with Translation & Rotation | Doginal | CFX | 2 | January 12, 2014 06:21 |
[ICEM] Hexa-Dominant mesh for a bended tube | dst | ANSYS Meshing & Geometry | 5 | October 9, 2013 16:27 |
[snappyHexMesh] snappyHexMesh won't work - zeros everywhere! | sc298 | OpenFOAM Meshing & Mesh Conversion | 2 | March 27, 2011 21:11 |
ICEM block mesh with a ball in a cylinder tube | Li | CFX | 6 | August 11, 2008 05:44 |
3-D Mesh Check in Gambit..... | SHR | FLUENT | 4 | March 25, 2003 03:10 |