Answer:
Mean velocity = 0.292 m/s
Maximum velocity = 0.584 m/s
The flow is laminar as Re = 229.2
Explanation:
D = 1.5 inches = 0.0381 m
Q = volumetric flow rate = 20 L/min = 0.000333 m³/s
Q = A × v
A = Cross sectional Area = πD²/4 = π(0.0381)²/4 = 0.00114 m²
v = average velocity
v = Q/A = 0.000333/0.00114 = 0.292 m/s
For flow in circular pipes, maximum velocity = 2 × average velocity = 2 × 0.292 = 0.584 m/s
To check if the flow is laminar or turbulent, we need its Reynolds number
Re = (ρvD)/μ
ρ = 1030 kg/m
v = 0.292 m/s
D = 1.5 inches = 0.0381 m
μ = 50 cP = 0.5 poise = 0.05 Pa.s
Re = (1030 × 0.292 × 0.0381)/0.05 = 229.2
For laminar flow, Re < 2100
For turbulent flow, Re > 4000
And 229.2 < 2100, hence, this flow is laminar.
