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Solving in cloud high mesh problems

103 Views, 13 Replies
02/09/2018 9:58 AM

Hi guys.

I'm wondering about this cloud solver. Instead of running the simulation on my computer i would like to solve them on the cloud. the problem is that when i use meshes up to 50million + elements, the problem takes some time, and i have to shut down my computer. The issue with this is that when the cloud have solved my problem and has no connection to upload to my computer (since offline), it fails. 
Is there any way to solve in cloud while offline and not fail?

Thanks in advance,
Isak


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Message 1 of 13 ( Views: 103 )

Re: Solving in cloud high mesh problems

02/09/2018 10:25 AM
I don’t yet understand the question.
I run on the cloud and once uploaded can turn my machine off. When back on it will reconnect and download the results.

Of course to upload or download we must be connected to the internet.

What is your experience exactly?

I am not sure I would want to run more than 50m elements though.
What sort of model are you running that requires such a large count?

Thanks,
Jon

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Message 2 of 13 ( Views: 93 )

Re: Solving in cloud high mesh problems

02/09/2018 10:42 AM

Alright! but that's good news. It might have been a storage issue. Past times i tried the cloud with high element count, it failed.  but i will try again (with enough storage space)

Its the same design with the gas lens, you thinks its a bit too much? right now its running at 7 mill mesh in the cloud. 

Thanks

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Message 3 of 13 ( Views: 88 )

Re: Solving in cloud high mesh problems

02/09/2018 2:01 PM

I definitely think you should be running a 1/2 model at most here. First thing to do with CFD is always to figure out how you can reduce the model to either:

 

  1. Run faster (in my experience time helps with money)
  2. Add more mesh to improve accuracy

I would also not add too many more scenarios to the project, it is easy to accidentally max out on memory with this.

 

This looks to be enough mesh, you could probably coarsen it a little in the larger areas, that are not the very tiny inlets.

Best way to understand this is to try it and compare results.

 

Hope that helps you,

Jon

 

 


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Message 4 of 13 ( Views: 80 )

Re: Solving in cloud high mesh problems

02/12/2018 8:23 AM

Good morning!

Came back after the weekend to find it failed the download. I don't understand why.
We will probably take !/2 model, and use smarter mesh. 

Thanks
Isak

failed.jpg


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Message 5 of 13 ( Views: 69 )

Re: Solving in cloud high mesh problems

02/12/2018 12:16 PM

My guess is antivirus/firewall/HDD space/write access.

 

Did you ever set up and exceptions to the AV/Firewall as in this article?


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Message 6 of 13 ( Views: 56 )

Re: Solving in cloud high mesh problems

02/12/2018 12:39 PM

sounds weird to me. I already managed to use the cloud solver when online all the time.

But i will read up on it anyway.

solver.jpg

thanks


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Message 7 of 13 ( Views: 52 )

Re: Solving in cloud high mesh problems

02/12/2018 12:45 PM

Agreed, that does sound weird.. Not sure I can explain it yet then.

Maybe try it incase so we can 100% rule it out?


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Message 8 of 13 ( Views: 49 )

Re: Solving in cloud high mesh problems

02/12/2018 1:14 PM

Alright, I've added all the programs as exceptions through the firewall as explained in your link.

A potential problem came to mind;
My laptop has no battery to save "time etc", the cmos or bios battery, thus it cannot retain any configuration memory while the system is turned off. This might cause problems? 

Thanks


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Message 9 of 13 ( Views: 46 )

Re: Solving in cloud high mesh problems

02/12/2018 1:19 PM

Yes, I would think that might be a problem. Hard to tell as it is not an issue I have seen before so something like this might explain it.

Could you try with a battery?!


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Message 10 of 13 ( Views: 44 )

Re: Solving in cloud high mesh problems

02/12/2018 1:21 PM

I could try with a battery!?!?!

I've read is a complicated thing to change that battery, but will look into it if it doesn't work with the current solver.

Keep you updated,

thanks,
Isak


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Message 11 of 13 ( Views: 42 )

Re: Solving in cloud high mesh problems

02/12/2018 6:59 PM

Hi @S316744,

 

Just a heads up, the cloud solving has access to ~128 GB of RAM, so roughly your max element count will be around 60something million elements. Also, if you hit the RAM limit, the solve will not fail on download or anything like that. You will get an error message in the UI saying "Max RAM limit exceeded". 

 

Thanks,



Matt Bemis

Technical Support Specialist


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Message 12 of 13 ( Views: 35 )

Re: Solving in cloud high mesh problems

02/13/2018 9:31 AM

Alright! thanks. We are currently running approx 6 mill element designs. The download part is a bit strange to me, some of the designs have download sizes at 3Gb, some at 30Gb. I might have done something weird in the setup. But i'm pretty sure its the same in all designs,

PS. Jon, the Cloud solver managed to solve a problem. So i'm out of ideas of what went wrong, will just see how the rest of them goes now :)

thanks,
isak
solver day 2.jpgsolver day22.jpg


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Message 13 of 13 ( Views: 25 )