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out of memory during assembly

Posted Aug 25, 2013, 9:33 p.m. EDT Mesh, Studies & Solvers Version 4.3b 2 Replies

Jiuan Wei
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Hi All,

I am running a heat transfer with radiation, and the error message says "out of memory during assembly". Rigth now, I am using a workstation with 48GB memory. I check the element number, and it has around 420K tetrahedral elements. Is this too large for my case? I used some other CFD software. Sometimes, I can handle the case with 7~8 million elements in a workstation.

The other quesiton is, when the case is running, there are two numbers to the memory in the right corner of GUI. Please refer to the picture attached. What is the meaning of them?

Thanks.


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2 Replies Last Post Sep 11, 2013, 6:24 p.m. EDT
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago Aug 26, 2013, 5:25 a.m. EDT

The two number are current memory use and estimate of the memory requirement at the end of the current processing step. I am using that to stop a calculation if I see it will not fit in my available memory.

Cheers
Edgar
--
Edgar J. Kaiser
emPhys Physical Technology
The two number are current memory use and estimate of the memory requirement at the end of the current processing step. I am using that to stop a calculation if I see it will not fit in my available memory. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology
Maciej Ochmanski
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Posted: 1 decade ago Sep 11, 2013, 6:24 p.m. EDT
Hi!

420k tetrahedral elements but what order? first-order?
default setting for comsol is second-order elements ('quadratic' under discretization tab)
from my experience if you change from second-order to first-order elements number of DOF will drasticly reduce which means that time to get results will be much shorter.
You need to remember that first-order elements produce results of lower quality.

p.s. in my opinion better is to use "DOF" to determine size of mesh
Hi! 420k tetrahedral elements but what order? first-order? default setting for comsol is second-order elements ('quadratic' under discretization tab) from my experience if you change from second-order to first-order elements number of DOF will drasticly reduce which means that time to get results will be much shorter. You need to remember that first-order elements produce results of lower quality. p.s. in my opinion better is to use "DOF" to determine size of mesh

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