Error: "Solver has stopped unexpectedly" after radiation set up complete message

[Anonymous]

Dear All,

I really need some help for troubleshooting the error in the Autodesk CFD software. 

I try to simulate a model, but the solver stopped working with an error message "solver has stopped unexpectedly" after message window showed "radiation problem set up complete" and the line in the bottom of the screen showed loading result phase 1 of 5. 
Actually, I already ran this model before in the same PC with the same Autodesk CFD version and it worked well. But now, every time I try to simulate the same model, it shows error like I mention above. I don't understand why it could happen. I already tried to follow the solutions given in this post (https://knowledge.autodesk.com/support/cfd/troubleshooting/caas/sfdcarticles/sfdcarticles/Error-Mess...) as well, but nothing worked in my case. 

Does anyone have any advice or suggestion to solve this error? I have tried to find out the solutions in some websites, including removing FlexNet license, managing user account control, turning off the firewall. But nothing worked. 

looking forward to any help. 

Thanks

[Jon.Wilde]

This could be memory? Is your RAM maxing out?

If you could run simulations before, I would not think it is anything like licencing etc.

[Anonymous]

Hi @Jon.Wilde

Do you mean the virtual memory? 

Actually, my PC has 24 GB RAM memory, but because I use Windows 7 Home Basic, the RAM memory that can be used limited to 8 GB. 

if the problem is in the RAM memory, why could I run the same model in the same PC with the same RAM capacity before. I don't really get it.

Do you have any suggestion how could I refresh my PC setting to the previous setting when I was still able to simulate the model?

Thanks in advance 

[Jon.Wilde]

Just a thought about the RAM - try monitoring it when you run to see if it maxes out?

Can you run a really simple model still?

[Anonymous]

Hi @Jon.Wilde

Attached is the screenshot of the used RAM when I run the simulation, it reaches 7.4 GB out of 8 GB. 

Yes, I can run the exhibit hall model from the Autodesk CFD tutorial folder. 

[Jon.Wilde]

OK, thanks for testing that.

Let's try two things:

1. Run it with the interface closed (saves on memory)
2. Run it without radiation

I think we can then limit the amount of RAM used by radiation if necessary (lowers accuracy though).

Thanks,

Jon

[Anonymous]

Hi @Jon.Wilde

Just want to inform some updates

So, two days ago, I uninstalled the Autodesk and delete the CFD 2016 folder in program files and ProgramData folder, I also delete adskflex_00691b00_tsf.data and adskflex_00691b00_tsf.data_backup.001 in FLEXnet folder. And then, I installed the CFD 2016 again. 

After doing this, I followed your instruction to close the CFD interface while running. And regarding the radiation, actually, my initial model was already without radiation. After that ,I tried to simulate the model again and the solver worked. Even after this, I tried to simulate the same model with radiation on and the solver still worked and even showed a convergence result (in around the 350th iteration). 

However, now, the same problem happen again in the Autodesk CFD software. And I already try to uninstall and install like what I did before, but the error can't be solved this time.

Do you have any other suggestion because I don't really know why this kind of error could happen.

Thanks

[Jon.Wilde]

Can you describe the exact steps you are taking when running?

What works and what doesn't? Same model? More designs/scenarios? etc...

(btw, I don't think you need to mess with the installation anymore)

[Anonymous]

So, actually, I created the model in my laptop and saved as cfz file. I
sent the cfz file to another PC where I ran the model.
In the PC, I opened the file and clicked the solve button and started
running the simulation.

Yes, I try to simulate the exact same model without changing anything.

At first, the solver showed an error message "solver has stopped
unexpectedly" after radiation set up complete showed in the window message.
And then I try to simulate without radiation and it kept showing the same
error.

Then, I tried to close the cfd interface while simulating and this time the
simulation worked fine until the simulation stopped due to convergence in
the 350th iteration.
(FYI, before trying to close the interface, I uninstalled and installed the
software again. I am not sure wheter closing the interface or
uninstalling/installing the software that solved the problem, that's whay I
mentioned about that in the previos post).

Because the solver has worked fine, I ran the second model, and it still
worked.

However, when I tried to simulate the third model, it showed the same
error again.

So, to check wheter the problem was in the solver or in the model, I tried
to simulate the first model again which was already succesfully simulated
before (without changing anything). But, it still showed the same error
like the first time.

I even tried to simulate the first model without radiation and it still
didn't work.

I don't get how could this happen?

[Jon.Wilde]

Me neither, yet 🙂

What happens if you right click and run CFD as admin?

Are the files all held locally also?

If you run CFDconfig (from the CFD installation folder) as admin, does that help?

Thanks,

Jon

[Anonymous]

Yes, all files are already on the local drive. 

I just tried to run the CFDconfig as administrator and also ran the CFD as administrator as well. But, it still didn't work. 

Should I attach the cfz file in here? So that, you can check if there will be the same error when you run it on your PC.

Below, I attach the png that shows the error message.

Thanks, 

Nurul

[Jon.Wilde]

Sure, let's see the CFZ 🙂

[Anonymous · Accepted solution]

Hi @Jon.Wilde

Thanks for your help

Finally, I solve this problem. So, actually, the problem is in the virtual memory allocation in my PC. 
In the previous setting on my PC, the "automatically manage paging file size for all drives" box is checked and it showed that currently allocated memory is lower than the recommended memory.
I solve this problem by unchecking the  "automatically manage paging file size for all drives" box and set the maximum size in the custom size section as recommended by the system.

I hope that it could be a useful information for other that found the same error.

Once again, thanks!

[Jon.Wilde · Accepted solution]

Thanks for the reply 🙂

I would suggest that means that in an ideal world, you would install more RAM. Ideally we don't want to be using the page files 😉

(They are slow)