Explain Reynolds Number.

Explanation

Osborne Reynolds oberved that turbulent flow is less likely for viscous fluid flowing at low rates.
He defined a dimensionless number , whose value gives idea whether the flow would be turbulent. This number is called the Reynolds `R_(e)`.
`R_(e)=(rhovd)/(eta)`
Where `rho` is the density of fluid ,v is the velocity of fluid , `eta` is the viscosity of fluid and d is the dimension (diameter) of the pipe.
From the value of Reynold.d number types of flow can be known.
If `R_(e)lt1000`, flow is streamline or laminar.
If `R_(e)gt2000` flow is turbulent.
If the value of `R_(e)` is between 1000 and 2000 then flow is unsteady.