Learning Forum

[xinsheng peng]

Always stuck at 5%....I don't know why

Is there anyone who can help me

[kghaffari]

Hi Xinsheng,

In my experience usually the long pause at 5% indicates that the mesh can’t/won’t be completed. Completing the mesh is usually the more challenging part of setting up the simulation in HEAT, because you need the large simulation region area to accurately account for the thermal behavior; while some of the features of the simulation can remain very small. This large aspect ratio requires lots of mesh cells and causes the challenges when obtaining mesh.

I have few general suggestions:

A) First try relaxing the mesh constraints. Coarsen the mesh to see if at some point this will cause the meshing to be completed; disable any local mesh objects and increase the min and max edge length values in the global settings drastically. The purpose here is testing whether this will resolve the issue, rather than the accuracy being the main concern.

B) If you obtain a mesh with the previous approach, gradually refine the mesh back until you find the most refined mesh that still successfully generates a mesh. Then you can further the accuracy by adding local mesh constraints to balance the computanional requirement vs accuracy.

C) If approach A doesn’t work, try changing the type of volume meshing. This is available for 3D simulations and for some geometries leads to better behavior. More details about the different options (e.g. vertex insertion) are provided here (Under Mesh tab section): https://optics.ansys.com/hc/en-us/articles/360034398234-HEAT-solver-Simulation-object

Best regards,

Khash