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Recommended PC specs for 3D High Frequency Acoustic-Structural Problems?

Posted Apr 28, 2011, 1:10 p.m. EDT Acoustics & Vibrations, Mesh, Studies & Solvers, Structural Mechanics Version 4.1 5 Replies

Kevin Richardson
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Hello,

I use COMSOL to model acoustic projectors at high frequencies in water. I typically solve for the far-field intensity field as well as the projector impedance and mechanical deflection. My models include the acoustic, basic electrical, and structural modules.

To accurately model high frequency acoustic models, I have found that performing 3D modeling gives me the best results but demand on my computer is intense. Oftentimes, I run out of memory or it will take an awful long time (>12 hrs) to solve the model. My computer is 64-bit with 4GB of RAM and quadcore processors at 2.0GHz. I have tried iterative solvers with no improvement in speed or in solving the model.

I talked to COMSOL support and they recommended more RAM and faster processors. Does anyone have recommendations for RAM size, core processor number, processor speed, and whether solid state memory is better than a regular drive to solve high frequency acoustic models with more than 1 million DOF?

Thanks again!

Kevin
5 Replies Last Post Apr 29, 2011, 9:30 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Apr 28, 2011, 2:57 p.m. EDT
Hi

I can only recommend to use more RAM, and try to avoid swapping, even on solid state disks, even if they are faster than rotating HD.

1 MDof I solve regularly on my 1 year old PC but. I have 2xcpu of 6x2 cores each and 48 GB RAM.
Then main annoying thing: it heats the office to >30°C and is noisy as a helicopter at take off, when all CPU's are at 100%
But from the moment I swap, I have <20 % efficiency.

For me it seems more efficient under Centos than Win7, for number crunching, but my CAD is only WIn7 compatible :(

--
Good luck
Ivar
Hi I can only recommend to use more RAM, and try to avoid swapping, even on solid state disks, even if they are faster than rotating HD. 1 MDof I solve regularly on my 1 year old PC but. I have 2xcpu of 6x2 cores each and 48 GB RAM. Then main annoying thing: it heats the office to >30°C and is noisy as a helicopter at take off, when all CPU's are at 100% But from the moment I swap, I have
Kevin Richardson
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Posted: 1 decade ago Apr 28, 2011, 6:08 p.m. EDT
Ivar,

Thanks for the recommendations. That is the information I needed.

Why would Windows 7 be different than Centos? I assume that Centos is Linux-based.

So you have 24 core processors at 48GB Ram total? What speed are the processors?

Kevin
Ivar, Thanks for the recommendations. That is the information I needed. Why would Windows 7 be different than Centos? I assume that Centos is Linux-based. So you have 24 core processors at 48GB Ram total? What speed are the processors? Kevin
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Apr 29, 2011, 1:33 a.m. EDT
Hi

well Linux is nice, as you mostly have few processes running, while with Win 7-64 you have the heavy load of MS applications difficult to get rid of, and reappearing at each update.

The thing is that I use Livelink to SolidWorks and that runs only on Win-7 hence I blocked, Matlab is compatible on both environments

My PC is a year old so its not up to date (3.33 GHz with fastest RAM) and today I assume I would have bought 128Gb of RAM :)

Anyhow I seldom launch more than half my CPU's as these are multi threaded, and that means that half of them they are sitting there often just waiting for bus access.
This means also I can have a solver going on in the background, and do my postprocessing in foreground on the other processors

But the noise and heat is annoying ;)

--
Good luck
Ivar
Hi well Linux is nice, as you mostly have few processes running, while with Win 7-64 you have the heavy load of MS applications difficult to get rid of, and reappearing at each update. The thing is that I use Livelink to SolidWorks and that runs only on Win-7 hence I blocked, Matlab is compatible on both environments My PC is a year old so its not up to date (3.33 GHz with fastest RAM) and today I assume I would have bought 128Gb of RAM :) Anyhow I seldom launch more than half my CPU's as these are multi threaded, and that means that half of them they are sitting there often just waiting for bus access. This means also I can have a solver going on in the background, and do my postprocessing in foreground on the other processors But the noise and heat is annoying ;) -- Good luck Ivar
Kevin Richardson
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Posted: 1 decade ago Apr 29, 2011, 8:55 a.m. EDT
Hi,

Thanks again for that information. I am looking at Alienware desktop that maxes out at 24GB of RAM and quad-core processor of 3.3GHz with 12MB of RAM. I think that is what our budget can get away with.

That should be an improvement on my current PC.

Kevin R.
Hi, Thanks again for that information. I am looking at Alienware desktop that maxes out at 24GB of RAM and quad-core processor of 3.3GHz with 12MB of RAM. I think that is what our budget can get away with. That should be an improvement on my current PC. Kevin R.
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Apr 29, 2011, 9:30 a.m. EDT
Hi

do not forget to have a good graphical card/driver My Nvidia quadro FX 1800 is working OK,

By the way the PC is a plain Intel motherboard, nothing fancy assembled from separate suppliers, but if you have a good price from a brand that's as good ;)

--
Good luck
Ivar
Hi do not forget to have a good graphical card/driver My Nvidia quadro FX 1800 is working OK, By the way the PC is a plain Intel motherboard, nothing fancy assembled from separate suppliers, but if you have a good price from a brand that's as good ;) -- Good luck Ivar

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