- Roshko number
In

fluid mechanics , the**Roshko number**is adimensionless number describing oscillating flow mechanisms. It is given as::$mathit\{Ro\}\; =\; \{St\}\; \{Re\}\; =\; \{f\; L^\{2\}over\; u\}$

where Ro is the dimensionless Roshko number, St is the dimensionless

Strouhal number , Re is theReynolds number , "f" is the frequency ofvortex shedding, "L" is the characteristic length (for example hydraulic diameter) and "ν" is thekinematic viscosity of the fluid.**ee also***

Reynolds number

*Strouhal number **References***Olim, A. M., Riethmuller, M. L., and Gameiro da Silva, M. C., 2002, "Flowfield characterization in the wake of a low-velocity heated sphere anemometer", "Exp. Fluids",

**32**, pp. 645-651.

*Ormieres, D., and Provansal, M., 1999, “Transition to turbulence in the wake of a sphere”, "Phys. Rev. Lett.",**83**, pp. 80-83.**External links*** [

*http://etd.caltech.edu/etd/available/etd-10302003-144124/ On the Development of Turbulent Wakes From Vortex Streets*] PhD. Thesis byAnatol Roshko (hosted on Caltech Site).

*Wikimedia Foundation.
2010.*

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