Non-engineer needs help with FLUENT!
 

Hello experts!

I have been posting here and there on the forums for a while now as a self-taught CFD user. I think I’ve come a decent way but need some help with the final parts of a test run.
Disclaimer – I’m a palaeontologist, I know next to squat about CFD except what I have taught myself in the past couple of months.

What I’m attempting to do is simulate fluid flow over the shells of ammonites; extinct free swimming molluscs.

I have 60+ 3D scans I have procured globally and basically would like to extract drag coefficient and torque values for the fossils at different orientations and Reynolds numbers.

I have taught myself FLUENT and have successfully validated my method using a 1 m sphere for which I managed to extract a CD of 0.35.

Using similar parameters I am simulating flow over a test fossil-scan at 1m/s (See pics). I believe I’m doing things correct but I’m having trouble getting convergence under a standard k-omega model and would appreciate any help.

Please bear in mind this is not an engineering issue, I am not interested in precision but in comparable results between fossils

Any help would be very much appreciated!