Rotameter Simulation
 

Hello!
I have a issue about rotameter (variable area flow meter) simulation using steady state and k-e turbulent model in COMSOL.
I create a cone tube and floater, then remove floater by difference.
Set inlet flow rate in bottom and 0 gauge pressure in top outlet.
I use -spf.T_stressz expreession compute drag force in floater and find out flow rate reach force balance with the floater weight of reference rotameter. However, I get the different value in experimental data. What are the reasons of the condition? The measuring fluid is air, so buoyancy can be ignored.

Has anyone ever simulated a rotameter? Could you provide some advice? Thanks!

https://lurl.cc/QQYq8