Error convergence of mesh optimization
Error convergence of mesh optimization
(OP)
Hi everyone,
Although I just signed up, I've been reading posts on this forum for a while now and I've found them quite helpful! Hopefully you guys can help me just as much. I am performing a thermal analysis on a set of cork-core sandwich panels with aluminum facesheets in ABAQUS. The sandwich panels, which are laterally isolated, are heated on one side/facesheet and the objective is to know the temperature on the other side.
The problem here is the mesh refinement. I performed various analysis with different meshes and ploted the value of the facesheet temperature vs. number of elements and as you would expect the value converges. This however is not enough to justify why I chose a specific number of elements for my mesh.
Is there any statistical method on Matlab that works with a desired value of the error of the temperature vs. number of elements function?
Thank you in advance,
Best Regards,
DPeixoto
Although I just signed up, I've been reading posts on this forum for a while now and I've found them quite helpful! Hopefully you guys can help me just as much. I am performing a thermal analysis on a set of cork-core sandwich panels with aluminum facesheets in ABAQUS. The sandwich panels, which are laterally isolated, are heated on one side/facesheet and the objective is to know the temperature on the other side.
The problem here is the mesh refinement. I performed various analysis with different meshes and ploted the value of the facesheet temperature vs. number of elements and as you would expect the value converges. This however is not enough to justify why I chose a specific number of elements for my mesh.
Is there any statistical method on Matlab that works with a desired value of the error of the temperature vs. number of elements function?
Thank you in advance,
Best Regards,
DPeixoto
RE: Error convergence of mesh optimization
No you can't predict the error from the mesh density for a general geometry, that is effectively doing the analysis before you've done the analysis.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Error convergence of mesh optimization
I already ran a set of analysis and came up with a temperature vs. no. of elements graphic!
Regards,
DPeixoto
RE: Error convergence of mesh optimization
http://reference.wolfram.com/applications/eda/Expe...
might be a good place to start
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Error convergence of mesh optimization
I was recommended using the richardson extrapolation to get the optimal number of elements for the mesh. Do you happen to know how somehting about this method?
Regards,
DPeixoto
RE: Error convergence of mesh optimization
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Error convergence of mesh optimization
You need to write a function that runs your FEA model, having scaled the mesh density by a factor Smesh, and returns one output value and then use that in the easily found matlab code for a richardson loop.
https://ece.uwaterloo.ca/~dwharder/NumericalAnalys...
The richardson bit is not the hard bit.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Error convergence of mesh optimization
Thanks again for your input and for helping me out, Greg!
RE: Error convergence of mesh optimization
for cpu=1:num_cpus
if run_adams==1
dos(['runadams' num2str(cpu) '.bat &'])
end
end
and runadams1.bat looks like this
call achassis -custadams C:/adams/Cust_ADAMS/R4/Personal_Py/apresolver_R4_x64.dll glts1.acf
!call needed otherwise dos box doesn't close
exit
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Error convergence of mesh optimization
How do I get this .bat file? It seems to me that the abaqus job file have either .inp or .odb extentions.
Also, I found a code that supposedly works with abaqus. How do I integrate the richardson extrapolation code with the abaqus code? (By making my function f(x) being the abaqus code below perhaps?). The code is as follows:
% Running regular jobs from within Matlab
% Note: These commands worked on a Windows Vista 64-bit PC.
% Running simple INPs - one after the other (2 here) - in batch mode:
clear all; clc;
dos('cd "DIR1" & "DIR\temp1.bat" && "C:\WINDOWS\system32\cmd.exe" /k exit')
dos('cd "DIR2" & "DIR\temp2.bat" && "C:\WINDOWS\system32\cmd.exe" /k exit')
% ..
% ..
% DIR1, DIR2 .. are the locations of the directories in which your INPs, temp1.bat,
% temp2.bat .. files respectively are placed
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Best Regards,
DPeixoto
RE: Error convergence of mesh optimization
The question now is, as you already pointed out, how do I extract the desired output values (Temperature vs. Number of elements)?
Is it possible to run manually the same job a certain amount of times with a different number of elements each time and put the resulting temperatures in a table a use that table in the richardson extrapolation?
Best Regards,
DPeixoto
RE: Error convergence of mesh optimization
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?