OBJECTIVE:
I am simulating a three cube one inside another to emulate the heat transfer between an aluminium cast piece at 600-700ºc approx (nucleus, smallest cube) and the mould structure (second cube) and the air (the biggest one that are an enclosure). I’ve built a model in SolidWorks combining the two cubes in an assembly, moving the smallest cube inside the big one (I haven’t created a cavity because it doesn’t leave me to differentiate the two cubes for selecting different materials) . After that, I uploaded a .zip file where both .sldprt and the assembly (.sldasm) files were uploaded. I have also created an enclosure for simulating the heat transfer in the behaviour.
PROBLEM:
The problem consists in an error when I try to simulate a conjugate heat transfer. I want to create a transient heat transfer where an initial temperature of the piece inside the mould starts at 600-700 ºC. I have made different meshes but a couple of errors appears before the progress of simulations arrives at 10% (in 10 min approximately the error appears). There are explained below:
These two types of errors consists in a “Maximum number of iterations exceeded when calculating temperature from a thermodynamic potential…”* I have made some verifications like refining the mesh or coarsing it, change the simulation parameters like time step or end time or uploading the files with another form.
When I change the mesh for a coarsed one the error changes at "*The solution diverged, please check your simulation setup. Divergence can also be caused by bad elements in the mesh…*I think that this problem is solutioned by refining the mesh but in that case the error consist in explained above.
It’s a vicious circle.
I don’t know if the problem is the way that I uploaded the files, if the mesh is generated incorrectly or something different. Could you help me?
Hi there, thank you for using the forum! 59k cells for this analysis is pretty coarse for this analysis, I am generating a mesh with the default Standard mesher settings, and will let you know how it goes
Keep in mind that you are simulating a compressible analysis now instead of incompressible(CHT v1 only supports compressible simulations)
But I can’t use the incompressible option because I need to simulate the heat transfer inside the mould as well. I’ve considered to simulate a CHT steady-state but the two errors are the same. May it be a problem of the CAD models? What could be the maximun runtime or divergence error?
Thanks for the guides. I’ve correct the CAD model as I read in those guides. I’ve created fillets in corners. Now I can simulate a bit. The maximum runtime errors is solved. I’ve simulated the heat transfer but I think may is not totally correct as you can see in the following image. The heat in the nucleus and the mould is not fully transferred to mould and air although I change the scale.
Furthermore, I tried to simulate the mould with an initial behaviour temperature different as 19.85 ºC (temperature that simscale automatically set) and in that case the problem of divergence continues.
