|
[Sponsors] |
May 15, 2013, 05:06 |
Solver can not produce result
|
#1 |
New Member
Join Date: May 2013
Posts: 10
Rep Power: 13 |
Hi All,
I am working on air flow over wing (subsonic and supersonic) and when I start solver, it worked few seconds and i see ,that message: "The solver failed with a non-zero exit code of: 2". After i can not edit setup because CFX-Pre have some error. When i try resolve this issue i saw that air does not flow through the connection of solids, which make up the model. But i don't know how connect this solids to air flow through them. This is image of my model with marked faces in which i have problem. |
|
May 15, 2013, 06:31 |
|
#2 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
You either need to remesh to make the mesh regions join up or connect them with GGI interfaces.
|
|
May 15, 2013, 15:54 |
|
#3 |
New Member
Join Date: May 2013
Posts: 10
Rep Power: 13 |
I connect this regions with GGI interface and Solver start but in iteration 46 the same error show up. I don't know if I set properly this interface or it's diffferent issue. If i post details of this error from Ansys or output from Solver it will help in the aid?
|
|
May 15, 2013, 18:24 |
|
#4 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
Please post your output file as an attachment, and some images of what you are seeing.
|
|
May 17, 2013, 09:39 |
|
#5 |
New Member
Join Date: May 2013
Posts: 10
Rep Power: 13 |
There is photo's, output file and error details:
|
|
May 17, 2013, 19:07 |
|
#6 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
Also what is the geometry? I have no idea what those blocks are. Some explanation would be useful.
You have had a divide by zero error. See this FAQ: http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F |
|
May 19, 2013, 07:55 |
|
#7 |
New Member
Join Date: May 2013
Posts: 10
Rep Power: 13 |
I want to simulate air flow over wing with subsonic and supersonic speed. I choose NACA 0009 profile to simple simulation. Midle block on geometry is space over a wing, left and right blocks are space in a front of wing and behind wing. My simulation is very similar to example in cfx tutorial (charper 10), so I modeled my geometry on this example. I mesh geometri and set boundaries like in this example and when I start solver for supersonic flow I see error, I wrote about early. So I make wrong geometry or mesh? Or I set wrong boundaries.
|
|
May 19, 2013, 10:46 |
|
#8 |
New Member
Roland Su
Join Date: May 2013
Posts: 5
Rep Power: 13 |
Hi,
Your analysis relate to external flow field. In the case as you describe, if you surpress the solid the geometry or mesh is commenly no wrong. Notice your boundaries and interface setting. |
|
May 19, 2013, 16:09 |
|
#9 |
New Member
Join Date: May 2013
Posts: 10
Rep Power: 13 |
Settings of boundaries and interfaces are on output file in post #5.
|
|
May 19, 2013, 19:33 |
|
#10 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
To model this supersonic you will probably need local timescale factor (using about 5.0) to start the convergence along, and once that is going switch back to phyisical time scale. And the physical time scale will need to be very small.
And mesh quality will be important. If the mesh adjacent to the airfoil is not nice you will have problems with convergence. |
|
May 21, 2013, 01:59 |
|
#11 |
New Member
Roland Su
Join Date: May 2013
Posts: 5
Rep Power: 13 |
Your FLOW REGIME:
Option = Supersonic and your MATERIAL: Air Ideal Gas The Air Ideal Gas is an incompressible fluid, for supersonic flow, you must choose the "Air at 25C". please try this.... |
|
May 21, 2013, 19:18 |
|
#12 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
Sorry Roland, you got them the wrong way round. "Air at 25C" is an incompressible fluid. You need to select "Air ideal gas" to active the compressible flow model.
|
|
May 21, 2013, 23:14 |
|
#13 |
New Member
Roland Su
Join Date: May 2013
Posts: 5
Rep Power: 13 |
Thanks ghorrocks, I have a wrong theory for ideal gas. Thank you!
But why dose the dlugi91's simulation have a non-linear P-Mass? Should he change the symmetrical bounderies to openning? |
|
May 22, 2013, 05:57 |
|
#14 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
Where does it say a non-linear P-Mass?
|
|
May 23, 2013, 00:13 |
|
#15 |
New Member
Roland Su
Join Date: May 2013
Posts: 5
Rep Power: 13 |
OUTER LOOP ITERATION = 44 CPU SECONDS = 4.967E+01
---------------------------------------------------------------------- | Equation | Rate | RMS Res | Max Res | Linear Solution | +----------------------+------+---------+---------+------------------+ | U-Mom | 0.28 | 1.6E-04 | 8.3E-03 | 2.8E-02 OK| | V-Mom | 0.23 | 6.2E-04 | 2.5E-02 | 5.8E-02 OK| | W-Mom | 0.23 | 5.0E-03 | 8.3E-02 | 4.3E-02 OK| | P-Mass | 0.01 | 2.9E-05 | 2.5E-03 | 8.6 4.9E+02 F | |
|
May 23, 2013, 06:31 |
|
#16 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
This is just non-cenvergence of the P-Mass equation. It means smaller time steps and/or better mesh quality is required.
|
|
May 23, 2013, 08:58 |
|
#17 |
New Member
Roland Su
Join Date: May 2013
Posts: 5
Rep Power: 13 |
Even more about the case. I met a situation, the time steps and mesh were correct, but the W-Mom or p-mass was non-linear. When I reseted the inlet boundary, the problem was resolved.
|
|
May 24, 2013, 06:16 |
|
#18 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,819
Rep Power: 144 |
Have you read the section in the CFX documentation about setting up boundary conditions and obtaining convergence? This discusses all these issues.
|
|
May 30, 2013, 09:13 |
|
#19 |
New Member
Join Date: May 2013
Posts: 10
Rep Power: 13 |
I finish my simulation with using Fluent and 2D model. Thanks all for help
|
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Creating New Solver: For particle-laden compressible jets | sankarv | OpenFOAM Running, Solving & CFD | 17 | December 3, 2014 19:41 |
OpenCL linear solver for OpenFoam 1.7 (alpha) will come out very soon | qinmaple | OpenFOAM Announcements from Other Sources | 4 | August 10, 2012 11:00 |
Working directory via command line | Luiz | CFX | 4 | March 6, 2011 20:02 |
How to compile an unsteady solver based on solver of MRFSimpleFoam? | renyun0511 | OpenFOAM Running, Solving & CFD | 0 | April 27, 2010 11:16 |
Creating New Solver: For particle-laden compressible jets | sankarv | OpenFOAM | 0 | April 4, 2010 18:06 |