Roshko determined the correlation below from experiments on the flow of air around circular cylinders over range Re=50 to Re=2000:
: valid over [ 50 <= Re <  200]
: valid over [200 <= Re < 2000]
Ormières and Provansal investigated vortex shedding in the wake of a sphere and found a relationship between Re and Ro in the range 280 < Re < 360.