CFD 2019 - Solve cycle does not complete

[DarrylD11]

Hi all,

I am having a recurring issue whenever I run a local simulation. After the solver has completed the iterations in solving the problem it seems to become hung. Therefore the job is not logged as complete and the next job in the queue cannot be run. It seems like the simulation manager does not detect that the solver has completed and therefore continues to allocate resources to the solver. The CFDSolver.exe process continues to use processing power and RAM without having any working set delta memory.

I have tried the uninstall - reinstall of the ServerManager as well as deleting the files in the Analyze folder. The same issue recurs. Pressing the "Stop" button also has no effect as it always tries to complete the "last iteration" when there are no more iterations to perform.

This means that I have to constantly "baby" each simulation and manually end the CDFSolver process after each iteration. This is proving to be a massive time-hog so any assistance in this regard will be greatly appreciated.

Best wishes from my end.

The message window reads as follows:

"

Turbulent Incompressible Flow is ON

Turbulence model: Standard k-epsilon

Intelligent Wall Formulation: ON

Begin Post-Processing Calculations ...

Post-Processing Calculations Done

Begin Post-Processing File Output ...

Post-Processing File Output Done

********************************

User stop request sent to server

********************************

Stop button selected. The analysis will stop at the end of the current iteration.

"

[David.Short.]

Hi @DarrylD11,

Thanks for reaching out on the forum hopefully we will be able to get this sorted as it sounds very frustrating.

A few questions:

1. How large are the simulations that you are running sequentially?

2. Does a single scenario run smoothly and complete quickly after the last iteration if it is run on its own i.e. not using the solver manager?

3. Have you applied the recommended firewall and antivirus exemptions? (they should be applied even if firewall and antivirus has been disabled)

All the best,

David

[DarrylD11]

Thank you for the response @David.Short.

The answers to your questions:

1. The simulations are average in size ranging from between 700k elements to around 4M elements for local solve. The simulation serves the purpose of  steady state internal forced convection analysis with a surface heat flux using variable fluid properties.

2. No, a single scenario encounters the same problem hence my frustration at having to "baby" the simulations. I have to resort to ending the solver process using Windows task manager. The solver does not exit after the final iteration.

3. Upon checking I noticed I hadn't included exceptions for the Simulation Job Manager. Those are now corrected.

It seems that if I run a small number of iterations (<20) then the solver behaves as it should. For larger amounts of iterations, however, the problem persists. I have tried running the simulation for 100 iterations and encountered the same problem. The project is on a local drive that has >400Gb space available. 

Kind regards,

DarrylD

[David.Short.]

Hi Darryl,

Thanks for the information. It sounds like you are doing everything correctly.

Please can you attach a .cfz of a scenario that you know will not finish.

All the best,

David

[DarrylD11]

Hi @David.Short.

I have attached the .cfz of the model I am currently running and experiencing problems with.

Another question, why does the software package copy and append the file name of the .cfz with "_support" ?

Best wishes,

DarrylD

[David.Short.]

Hi Darryl,

Please can you run the attached on your machine and let me know if it completes correctly. It is your model but with some modified settings and it runs fine on my machine.

All the best,

David

[DarrylD11]

Hi David,

I'm busy running the .cfz that you sent on to me. I will get back to you with the results when it's completed.

I have a few questions in the meantime.

1. Is there any particular reason why the heat flux boundary condition was changed to heat gen?

2. Automatic mesh and refinement discarded in favour of manual mesh size?

Thank you for your assistance thus far.

Darryl

[David.Short.]

If it runs successfully then lets get into those questions 😉

If it doesn't run then its not worth discussing them as they are simply settings that i know are normally stable.

All the best,

David

[DarrylD11]

Hi David,

So the simulation has completed in that all the iterations are done. However, the solver has not exited so I have the same problem.

Any suggestions?

Best wishes,

Darryl

[David.Short.]

Ah shame! 

To me it really sounds like Antivirus / firewall exemptions.

Also do you have any automatic backup or syncing with dropbox going on?

Shot in the dark: Run the CFDconfig.exe file as administrator (found under CFD2019 in program files). This will do a quick reinstall. Note that you should save any custom materials to a local drive as they will be lost in the reinstall.

All the best,

David

[DarrylD11]

Hi @David.Short.,

I apologise for the delayed response. I hadn't had an opportunity to test it again.

I checked the firewall settings and I am using Windows Defender with exceptions made for Autodesk products.

Nope, no automatic backup or syncing is occurring.

I tried running the CFDConfig as you recommended and attempted solving the model you sent me with the same problem. I have clean uninstalled CFD 2019 and performed a re-install as well (and re-applied firewall / anti-virus exemptions). 

Interestingly, if I press the "end" button in the solver dialog when there are still iterations outstanding the process exits without a hitch. Is this helpful?

Best wishes,

Darryl

[David.Short.]

Hi Darryl,

Are you using a multi user license? If so please can you try borrowing the license for a day such that it is actually on the local machine and we can rule out network issues effecting the sims?

You can borrow the license under "manage license" in the dropdown next to your name in the top right corner.

All the best,

David

[David.Short.]

For other viewers interest I also recommended Darryl to switch the installation location to his C drive however this did not help.

[David.Short.]

Darryl please can you also try running this tutorial model on your machine and let me know how it goes.

[DarrylD11]

Hi David,

I am currently using a device licence so I am unsure where or how I would be able to acquire a multi-user license.

Best wishes,

Darryl

[Jon.Wilde]

Random thought from me, are you running from a local folder? One just on your C drive for example?

[DarrylD11]

Hi @Jon.Wilde,

Thanks for your input.

The project folder is on a drive local of the computer I am using. Different drive to that of the install though. CFD 2019 is running on an internal SSD ("C:" same as Windows) and the project on a HDD ("D:") due to space constraints and write cycles of the SSD.

Regards,

Darryl

[David.Short.]

How did you get on running the tutorial model Darryl?

[DarrylD11]

No issues whatsoever. Just to check if @Jon.Wilde's hunch was correct I ran the tutorial from the same directory as my current project. I'm baffled... 

EDIT: Again, if I manually stop the simulation using the "stop"button before the final iteration then everything performs as normal.

[David.Short.]

Hmmmm so the issue is project specific then. How long have you waited before killing the solve in task manager?

Did you run the .cfz of your model that i sent exactly as it was?

If so please attach your latest .cfz and we can have another go.

All the best,

David