Roshko number
In fluid mechanics, the Roshko number is a dimensionless number describing oscillating flow mechanisms. It is named after the Canadian Professor of Aeronautics Anatol Roshko. It is defined as
where
- St is the dimensionless Strouhal number;
- Re is the Reynolds number;
- U is mean stream velocity;f is the frequency of vortex shedding;L is the characteristic length ;ν is the kinematic viscosity of the fluid.
Correlations
Roshko determined the correlation below from experiments on the flow of air around circular cylinders over range Re=50 to 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.