Answer:
C. fluid density & viscosity
Explanation:
In 1850, Darcy-Weisbach experimentally deduced an equation to calculate shear losses ("friction"), in a tube with permanent flow and constant diameter:
hf = (f x L x V^2) / (D x 2g)
where:
hf: shear losses
f: shear loss factor (pipe roughness)
g: gravity acceleration
D: tube diameter
L: tube length
V: fluid average speed in the tube
To calculate the loss factor “f” in the Poiseuille laminar region, he proposed in 1846 the following equation:
f = 64 / Re
Where:
Re: Reynolds number
The influence of the parameters on f is quantitatively different according to the characteristics of the current.
In any straight pipeline that transports a liquid at a certain temperature, there is a critical speed below which the regimen is laminar. This critical value that marks the transition between the two regimes, laminar and turbulent, corresponds to a Re = 2300, although in practice, between 2000 and 4000 the situation is quite inaccurate. Thus:
Re <2000: laminar regimen
2000 <Re <4000: critical or transition zone
Re> 4000: turbulent regime