Learning Forum

[upot2]

Hello,

I am working with a coldplate model (with glycol as the coolant) in Icepak currently. The model was created in Solidworks, taken through Spaceclaim to create fluid regions and convert everything to Icepak bodies and then bought into Icepak. I have enabled multi-level meshing and the mesh looks good with a good minimum face alignment. However, when I run the solution for 100 iterations, the residuals start to diverge around 50 iterations.

On closer inspection, I observe Fluent gives me a warning before solving which says 'Material of cell zone 25 is glycol-50, while material of cell zone 82 is air. This will adversely affect the solution. Please correct the setup.' I have glycol flowing through the coldplate and air for natural convection outside the coldplate and have attached an image of the model for reference. The shaded regions represent fins. Could anyone let me know how I go about correcting this or checking where exactly these cells are? 

 

Thanks

[Satyajeet Padhi]

Hi upot2, 

 

Material of cell zone 25 is glycol-50, while material of cell zone 82 is air. This will adversely affect the solution. Please correct the setup

 

You will see this error if the two fluids (i.e., air and glycol) are touching each other at some location. This could be near the opening where the coolant is introduced or some other location where the mesh is coarse such that the glycol zones are touching the air zones. You would need to closely inspect the areas that are carrying glycol. 

Suggestion: Don't have any fluid channels for the cold plate enclosure. Make it one solid body. Then for the fluid channels (i.e., glycol) convert the cold channels to Icepak compatible body and then select the face of the inlet and outlet to convert them to openings. Then in Icepak, use meshing priority to assign a higher meshing priority to the fluid (glycol) channel.