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inaccurate temperature profiles and meshing related

Posted Nov 3, 2011, 12:51 p.m. EDT Heat Transfer & Phase Change, Mesh, Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4.1 2 Replies

Supradeep Narayana
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gaining temperature!!

1. I am running some simple calibration tests for temperature profiles and
heat conduction.
2. I take two blocks (one with very low conductivity
and other with very high conductivity).
3. I applied temperature to only one side of one of the blocks.

According to the profile shown, it looks to gain temperature( by looking at the data range of the surface
temperature profile from 400k to 400.00000000342084k ),this is with the extremely fine mesh setting.

With coarse mesh setting, the temperature is all uniform.
could somebody help explain this mystery to me!!!

2 Replies Last Post Nov 4, 2011, 3:25 a.m. EDT
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago Nov 3, 2011, 10:19 p.m. EDT
The gained temperature of 3.4e-9 K is well within the range of numerical round off errors.

Nagi Elabbasi
Veryst Engineering
The gained temperature of 3.4e-9 K is well within the range of numerical round off errors. Nagi Elabbasi Veryst Engineering
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago Nov 4, 2011, 3:25 a.m. EDT
Hi

and do not forget how numbers are represented in a computer, binary distribution has a limited precision and tricky uneven distribution over the real numbers. So I never trust differences much above 1:1E6

--
Good luck
Ivar
Hi and do not forget how numbers are represented in a computer, binary distribution has a limited precision and tricky uneven distribution over the real numbers. So I never trust differences much above 1:1E6 -- Good luck Ivar

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