Question

water enters a 0.1m diameter pipe. find the volume flow rate at which the flow becomes turbulent m=1.4x 10^-3 Ns/m^2, row 999kg/m3

Answer 1

The flow becomes turbulent when Reynolds number = 4000

Diameter of pipe = 0.1 m

Density of water = 999 kg/m3

Viscosity = 1.4x 10^-3 Ns/m2

Reynolds number = diameter x velocity x density / viscosity

Volumetric flow rate = Area x velocity

Volumetric flow rate = (3.14/4)*diameter x diameter x velocity

Velocity = (Volumetric flow rate) / [(3.14/4) x diameter x diameter]

Reynolds number = [4 x Volumetric flow rate x density] / [3.14 x diameter x viscosity]

4000 = (4 x Volumetric flow rate x 999 kg/m3) / (3.14 x 0.1 M x 1.4 x 10^-3 Ns/m2)

4000 = (3996 x Volumetric flow rate) /(0.0004396)

4000 = 9090081.89 x Volumetric flow rate

Volumetric flow rate = 0.00044 m3/s