I need to help for my case. I want to model an industrial-scale CFB boiler with internal baffles. I tried to solve it at different times and different meshing and modeling approaches.
This is my geometry. My boiler has a one rectangular baffle + some u beams.
When I tried to run with just a rectangular baffle, my problem can be solved. But I try to mesh for u beams, my simulation can’t be converged. So, I create a lot of internal (impermeable) surfaces that act as u-beams. But free-slip conditions applied on internal surfaces.
I said OK for laminar conditions. After the first run, I want to run with turbulence conditions.
When I try to run with turbulent conditions (either k-epsilon or l-scale), simulation say to me “Singular matrix detected when solving: E_Turb_G” and finally “Negative density detected”.
This is my problem with meshing. My grids always have some gaps like that. I tried different grid sizes, adding some control points, etc. but I didn’t do perfect meshing. Also, I tried different resolutions for STL files but saw similar results.
kazanubeam_2020-12-12T053217.111801.zip (28.0 MB)