Example – Calculating Reynolds Number
A Newtonian fluid with a dynamic or absolute viscosity of 0.38 Ns/m2 and a specific gravity of 0.91 flows through a 25 mm diameter pipe with a velocity of 2.6 m/s.
The density can be calculated using the specific gravity like
ρ = 0.91 (1000 kg/m3)
= 910 kg/m3
The Reynolds Number can then be calculated using equation (1) like
Re = (910 kg/m3) (2.6 m/s) (25 mm) (10-3 m/mm) / (0.38 Ns/m2)
= 156 (kg m / s2)/N
= 156 ~ Laminar flow
(1 N = 1 kg m / s2)
