|
[Sponsors] |
August 21, 2014, 00:50 |
Problem with multidomain interface
|
#1 |
New Member
José
Join Date: May 2014
Location: Argentina
Posts: 7
Rep Power: 12 |
Sory for the interruption, I'm getting started with ansys cfx and I've been having lots of trouble with modeling a sudden high pressure vessel discharge into atmosphere.
What I've done so far is to create a multibody part in DM, then mesh it in the Ansys Meshing program with a sweep method, making sure that mesh is conformal between my two bodies (tank and discharge zone) and later set in the Pre two domains with an interface between them and each of them with their corrsponding initialization. The problem arises when I get to Post and find that there is no mass flow between domains, as if there was no discharge, and abs. pressures remains the same. I'd appreciate any answer, and sory again for the interruption. |
|
August 21, 2014, 06:58 |
|
#2 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,854
Rep Power: 144 |
No need to apologise for the interruption, the forum is here to ask questions.
It sounds like you have not applied your interface correctly, so the two domains are not connected. In fact there is no reason to do this as a multidomain problem, it can easily be done as a single domain with an initial condition. Then you do not need interfaces (which is slightly preferable, there is a small computing overhead in including interfaces). |
|
August 21, 2014, 10:40 |
|
#3 |
New Member
José
Join Date: May 2014
Location: Argentina
Posts: 7
Rep Power: 12 |
First of all, thanks for your reply Glenn.
Ok, I thought I needed two domains due to distinct initial conditions between them (one at high pressure and the other one at atmosphere conditions). Then, if the problem can be solved using a single domain, how do I set the different initial pressures between the two regions of the domain? |
|
August 21, 2014, 11:04 |
|
#4 |
Senior Member
Join Date: Jun 2009
Posts: 1,873
Rep Power: 33 |
Relative Pressure = High Pressure * inside()@Volume 1 + Low Pressure * inside()@Volume 2
the inside()@Location is 1 within the location, and 0 elsewhere. |
|
August 21, 2014, 11:10 |
|
#5 |
New Member
José
Join Date: May 2014
Location: Argentina
Posts: 7
Rep Power: 12 |
Brilliant!!!
Do you know about any good manual from where I can learn that syntax? |
|
August 21, 2014, 21:38 |
|
#6 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,854
Rep Power: 144 |
The CFX Reference manual, in the section on Variables, functions and CEL.
|
|
August 22, 2014, 20:26 |
|
#7 |
New Member
José
Join Date: May 2014
Location: Argentina
Posts: 7
Rep Power: 12 |
Thank you Glenn,
Now I've done what you've told me but again I'm having the same problem. I got rid of the interface and instead applied a single domain with different pressures at the initialization. Mesh seems to be conformal as in the connectivity icon of the Pre both faces appear as a 1:1 connection. Maybe there's a parameter I'm totally unaware of that's making this section to work as a wall, but I've double checked it. Also it's kind of weird that in the Post the streamlines are drawn in the particular way I expect the flow to discharge though the colorbar tells me the velocity value is almost zero (frustrating when I'm expecting supersonic flow at discharge area). Thanks again! |
|
Tags |
interface domains, multidomain |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Wind turbine simulation | Saturn | CFX | 60 | July 17, 2024 06:45 |
[ICEM] ADINA interface problem | Daniel_Khazaei | ANSYS Meshing & Geometry | 3 | May 5, 2014 07:58 |
Radiation interface | hinca | CFX | 15 | January 26, 2014 18:11 |
interface boundary problem | Rashad | FLUENT | 0 | April 23, 2007 06:27 |
Replace periodic by inlet-outlet pair | lego | CFX | 3 | November 5, 2002 21:09 |