Good afternoon, I did a simple simulation using two constraint heatflux, I used a cube, the material was Calculix-Steel, the both constraint heatflux are in the top and the bottom of the cube, I selected the higgest mesh, the top constraint heatflux is -0.50 W/m^2 and the bottom is 1.00 W/m^2, the constraint initial temperature was 300 K, I am using Freecad 0.20, everything is fine in "write .inp file" but there is an error when I "run Calculix", What I am doing wrong?
Beforehand thank you so much.
OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.20.26858 (Git)
Build type: Release
Branch: master
Hash: e209bc706d35121098f9bac779bc6b09c24ddd95
Python version: 3.8.6+
Qt version: 5.15.2
Coin version: 4.0.1
OCC version: 7.5.3
Locale: Spanish/Mexico (es_MX)
Simulation error using two Constraint Heatflux
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Simulation error using two Constraint Heatflux
- Attachments
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- error.png (134.22 KiB) Viewed 1414 times
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- bottom.png (130.82 KiB) Viewed 1414 times
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- top.png (132.22 KiB) Viewed 1414 times
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- meshing.png (131.96 KiB) Viewed 1414 times
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- material.png (129.49 KiB) Viewed 1414 times
Re: Simulation error using two Constraint Heatflux
Can you attach the .FCStd file ? Are there any additional error messages in the Report View window ? So far I can only suspect that the problem is caused by the lack of mechanical constraints (that's a thermomechanical, not pure thermal analysis after all).
By the way, the mesh is definitely too coarse.
By the way, the mesh is definitely too coarse.
Re: Simulation error using two Constraint Heatflux
Sure, I am going to attach it, sorry for that.NewJoker wrote: ↑Tue Jan 18, 2022 9:59 pm Can you attach the .FCStd file ? Are there any additional error messages in the Report View window ? So far I can only suspect that the problem is caused by the lack of mechanical constraints (that's a thermomechanical, not pure thermal analysis after all).
By the way, the mesh is definitely too coarse.
- Attachments
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- exampleproject.FCStd
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Re: Simulation error using two Constraint Heatflux
The analysis doesn't converge with these boundary conditions - the solver can't find the steady-state solution. It should work if you switch to transient but make sure that thermal constraints are correct in this case. They should correspond to a real-life conditions of a structure that you want to analyze or (when it's just a theoretical consideration) at least make sense in terms of underlying physics.