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cumulo_nimbus
Posts: 7
Registered: ‎05-12-2013

Error message at Boundary Condition Data setting

224 Views, 5 Replies
05-12-2013 01:28 AM

Hi, I understand web and phone support is only for active subscription (paid sub?), and not academic subscriptions. Thus I would like to post my request for help here. I was not able to proceed with my CFD simulation because at/after the BC data stage an error appears.

 

The error window asks me to send the .cfz file to the support staff but I cant seem to find any support. My cfz file is attached if anyone would be kind enough to help me look at it. The log file is also attached. It seems to say

 

[12:01:59] ### Critical: source\clt_runwidget.cpp 703
The Analysis has stopped because the Solver has exited unexpectedly

 

I am basically taking a geometry from revit architecture and trying to simulate with a simple laminar wind flow.

 

Appreciate any form of assistance. Thanks!

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wildej
Posts: 733
Registered: ‎08-25-2011

Re: Error message at Boundary Condition Data setting

05-13-2013 02:03 AM in reply to: cumulo_nimbus

Hello,

 

This sounds like you have the wrong Boundary Conditions assigned.

If you are running a wind tunnel type analysis, you only really need 2 Boundary Conditions.

 

An inlet flow rate or velocity on the inlet

A p=0 at the outlet.

 

You can add slip/symmetry on the side walls/top if you wanted, to remove the friction.

 

Hope that helps.

 

Regards,

Jon

 



Jon Wilde
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Royce_adsk
Posts: 555
Registered: ‎08-24-2011

Re: Error message at Boundary Condition Data setting

05-13-2013 11:43 AM in reply to: cumulo_nimbus
External surfaces that do not have a boundary condition are defaulted to a 0 Velocity or no-slip wall assumption. You can remove all the 0 Normal velocity components.

Also, you do not need to define 0 velocity for your initial conditions.

Are you sure using laminar is appropriate for this model? I would probably stick with default settings.

-Royce


Royce Abel
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Contributor
c3110765
Posts: 18
Registered: ‎07-08-2013

Re: Error message at Boundary Condition Data setting

08-25-2013 01:17 AM in reply to: Royce_adsk

Hello,

 

I have the same situation as "cumulo_nimbus". my Simulation CFD solver exits unexpectedly upon reaching the "processing input" stage of the solving process. I have attached a copy of the .cfd file I was advised by the program to submit.

 

The context of this program is the construction of a simple 6m square house in Autodesk Revit, using generic models, which has then been loaded into Simulation CFD for a solar heating thermal analysis. I hope to understand the heating effects on the internal brick partition walls, with the sun heating the building through a north facing window and a thermally insulated ceiling preventing downward heating through the roof.

 

I would also be interested in obtaining further support through either basic support or advanced support, however I am a student completing this project as part of a research thesis, and as such do not have an autodesk subscription. Am i able to purchase a subscription alone, in the interest of gaining either web or phone support on a one to one basis?

 

I appreciate your help in this matter.

 

Regards,

 

Ron

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Contributor
rsmith
Posts: 20
Registered: ‎11-30-2011

Re: Error message at Boundary Condition Data setting

06-22-2014 02:11 PM in reply to: c3110765

I got this error as well ("Solver Exited Unexpectadely...", with "[16:34:37] ### Critical: source\clt_runwidget.cpp 688" in the log file). I fixed it in my case. I unchecked "Stream Function" in my result quantities and ran again for 0 iterations. Probelm solved.

 

It was solving just fine, it only "exited unexpectadely" when the the solve reached the specified stop time or when I manually stopped the solve. I had the last time step results (no saved intervals though), and critical values were calculated. I could not clone the scenario though. The strangest thing was I had been restarting and stopping the analysis every few hundered iterations with no problem. It just started happening seemingly randomly.  

 

I don't know why it worked, or if it is "Stream Function" specifically. Maybe it was just making a change to the requested qty's that did the trick.  

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Product Support
wildej
Posts: 733
Registered: ‎08-25-2011

Re: Error message at Boundary Condition Data setting

06-23-2014 01:47 AM in reply to: c3110765

c3110765 can I suggest we start a new thread for your question as it does not relate to the above model?

 

Some comments first which might help you solve this:

 

  1. Your materials are muddled, your walls are air and your air dome is brick
  2. Your mesh is too coarse
  3. As you are running transient, all volumes need initial temperature conditions
  4. Your timestep is too large if you plan to run flow, likely also too large for heat transfer
  5. Should flow really be turned off? This will likely need to drastically escalated temperatues

If you need anything further, let's start a new thread and talk in detail.

 

Hope that helps,

Jon



Jon Wilde
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