[cgswjs]

Hi guys,
I'm new to star ccm+ and I'm doing a project about a double pipe heat exchanger with turbulators in the annulus region. I've got the mesh and deleted bad cells. Boundary conditions are velocity inlet and pressure outlet for inner pipe fluid region, mass flow inlet and pressure outlet for annulus fluid region. I've been trying to run the simulation with different sets of meshing and they all have this Bi-conjugated not diverge error. The spike always shows up around 60th step. Can someone help me with this problem? I don't know where to start to fix this. Btw, I used K-E turbulence model for the annulus flow.

[me3840]

Originally Posted by cgswjs

Hi guys,
I've got the mesh and deleted bad cells.

This is generally not a good sign. Have you inspected your mesh quality? Please post images of your mesh.



If you look at the blown up solution your should be able to see where velocities and temperatures are very high, which will point to the problem.