An airflow of 1,000 L/s flows through a round sheet metal duct that is 300 mm in diameter and 100 m long. The air temperature is 12 C and the pressure is atmospheric. Determine the friction pressure drop (Pa). Use Equation 3.47 in the textbook to calculate the friction factor.

Given the following;

dynamic viscosity μ = 1.78 x 10^-5 kg/m. s

L = length of pipe = 100m

D = diameter of pipe = 300mm = 0.3m

u = flow rate = 1,000 L/s = 1m³/s

from the formulae for pressure drop = 128μLu / πD^4

Plugging the values into the equation = 128 x 1.78 x 10^-5 x 100 x 1 / π x 0.3^4

= 8.9535Pa = the friction pressure drop (Pa)