[sasanghomi]

Hi dear max ,

I dont know anything about size function Can you explain more? Or Do you have any tutorial??
Thanks and best regards

[-mAx-]

http://aerojet.engr.ucdavis.edu/gamb...ide/mg0502.htm

[Volumeoffluid]

Originally Posted by -mAx-

no need to use interface, you can use size function for that

Hi max,
i just read your comments and they are really intresitng. So i have a problem too and i ll appreciate if you can help me.
So i ll try to describe my problem.
So when i use VOF model my programm cannot recognize the two different phases. When i change one phase (air) automatically changing the other (water)...I don't understand why this happen.
Specially....there was this message: Unassigned interface zone detected for interface xx (This is the line between air-water)
I should define this mesh interface, but i dont know how exactly i can do this...
I adjusted some options in Meshing and Designmodeler but the same warning again.
I can send you photos of my project.
I dont know if it was better to use two different meshes
Thank you in advance!

[-mAx-]

Again, don't mix "interface" in the sense of Mesh (here in Fluent) with interface (multiphase)
Post pictures of what you want to compute

[Volumeoffluid]

Originally Posted by -mAx-

Again, don't mix "interface" in the sense of Mesh (here in Fluent) with interface (multiphase)
Post pictures of what you want to compute

nice!so could you send me your email to send you my geometry or some pictures?
My email is jimromanas@hotmail.com
thank you a lot!

[Volumeoffluid]

This is my geometry of my problem.
I hope i am clear of my questions

[-mAx-]

explain your physics, where are phase1, phase2. Where is your "interface", etc...

[Volumeoffluid]

so from the left the half-circle is my bubble(air) and the other Rectangle is my surface (water).The line between these is my 'interface'. So i want o use VOF model to describe how is my bubble's behavior.
So when i use VOF model my programm cannot recognize the two different phases. When i change one phase (air) automatically changing the other (water)...I don't understand why this happen.
Specially....there was this message: Unassigned interface zone detected for interface xx
I should define this mesh interface, but i dont know how exactly i can do this...
I have the same mesh both bubble and the other surface.

[-mAx-]

As I said, forget interfaces.
Reconnect both domains (connect edges (All)), but keep your split line (half-circle)
Then you have to define 2 continuum types:
one for air and one for water
https://www.sharcnet.ca/Software/Gam...zone_cont_type
Then later in fluent you will be able to set your vof properly
EDIT: Next post remind me that you are probably not working with Gambit...

[Vidyanand Kesti]

Interface is just connect the mesh or grids and help to flux transfer, If its automatically creating interface in the fluent please check in the ANSYS mesher, delete the connection in the AMP, if you check the grid check in fluent its shows the warning because of interface, define the interface in fluent to avoid the this warning, If you get the wall between two interface means in model it had gap in between the two interface ,so convert to interior or back to model fill the gap either by solid extrude or extrude

[Volumeoffluid]

Thank you both for your answers.So,
dear Max i did exactly what you said, but when i go to fluent, it was created two BC for this split lines (half-circle)...one is from bubble side and the other from surface side. So for one line, there are two lines. I had name selection but the fluent create and the other line for surface side. I dont use anymore interface.What should define these lines?as wall??and mesh motion and in VOF model (explicit sheme---> Geo-reconstruct) ??
i have defined the (before used VOF) two cell zones(one with air and other with water)...but again when i used VOF, when i change one cell zone condition automatically the other same change.

P.S i use Ansys Fluent 14.5.7 (DesignModeler- Ansys Meshing- Ansys Fluent)

Dear vidyanand.kesti@mann-humm,
in Ansys Meshing i disabled automatic insert contact region. So i have only in my outline tree one Connection. Nothing Else. And i did exactly what i had described above.
I am looking forward your answers
Thank you!

[-mAx-]

Originally Posted by Volumeoffluid

P.S i use Ansys Fluent 14.5.7 (DesignModeler- Ansys Meshing- Ansys Fluent)

If you don't have Gambit, then you cannot do what I mentionned.
I let other people helping you since I don't know Ansys Meshing

[Volumeoffluid]

Ok Max thank you a lot for your mentions, but
do you know someone that he can help me??
i should contact immediately with him!

[-mAx-]

Maybe Far can help you

[Volumeoffluid]

Because i dont know him (Far), can you send me his profile or URL something to find him?
Thank you!

[thermal energy]

Originally Posted by Vidyanand Kesti

Interface is just connect the mesh or grids and help to flux transfer, If its automatically creating interface in the fluent please check in the ANSYS mesher, delete the connection in the AMP, if you check the grid check in fluent its shows the warning because of interface, define the interface in fluent to avoid the this warning, If you get the wall between two interface means in model it had gap in between the two interface ,so convert to interior or back to model fill the gap either by solid extrude or extrude

dear vidyanand,

when ı check the grid as you said it shows warning because of interface, how do ı define interface in fluent. ı have phase change materias-air interface. they dont penetrate eachother. ı define this line as an interface boundry condition but ı have error.thanks for your help.

WARNING: Unassigned interface zone detected for interface 5
Error: Init_Flow: unassigned interface_zones

[6863523]

Originally Posted by thermal energy

dear vidyanand,

when ı check the grid as you said it shows warning because of interface, how do ı define interface in fluent. ı have phase change materias-air interface. they dont penetrate eachother. ı define this line as an interface boundry condition but ı have error.thanks for your help.

WARNING: Unassigned interface zone detected for interface 5
Error: Init_Flow: unassigned interface_zones

Hi,
I am simulating the evaporation right now. I have no idea whick kind of boundary type should I specify for the porous-vapor interface.
The porous is saturated with liquid water. There is a heat flux at the bottom of the porous. The evaporation occurs at the upper surface of the porous.

http://www.cfd-online.com/Forums/mem...interface.html

In fluent, what kind of boundary type should I choose for the interface to let the liquid water flow into vapor region.

I used Gambit to mesh.
Since the porous rigion and vapor region overlaps, I named the overlapping two edges as interfaces.

http://www.cfd-online.com/Forums/mem...-interface.png

After I imported the mesh, I created the mesh interface correspondingly as below.
http://www.cfd-online.com/Forums/mem...-interface.png

Thank you in advance. I have been stuck here for a long time. My email: 815719752@qq.com
Hope to hear from you soon.
Best Regards,
Bill

[ksujeet213@]

hii guys i am new in cfd....i have an question?
how to apply boundary condition at interface?

[pakk]

You should tell us what you really want to do. Which problem do you think you can solve by putting a boundary condition on an interface?

[ksujeet213@]

my question is

for piping networking analsys where at interface portion i want to provide pressure drop for heat exchanger on mixing network route?