Question

Find the total friction loss in 100 mm diameter G.I. pipe discharging 4 L/s ina total length of 300 m. Assume pipe roughness, ε = 0.20 m. (hint: use the nomogram, use the head loss equation(darcy-weisbach equation) to calculate, hf and moody's diagram to estimate friction factor, f and compare the result.)

Answer 1

total friction is 0.9903 m

Step-by-step explanation:

given data

diameter D = 100 mm = 0.1 m

discharge Q = 4 L/s = 0.004 m³/s

total length L = 300 m

roughness ∈ = 0.2 mm

solution

we get here total friction loss hf that is express as

hf =
`(f*L*V^2)/(2g*D)` ......................1

first we get here Reynold's no that is

Re =
`(V*D)/(\gamma)` ................2

Re =
`(((0.004)/(\pi*0.1^2/4))*0.1)/(10^(-6))`

Re = 50900

so here f is 0.025 by moody diagram

so put all value in equation 1 we get

hf =
`(0.025*300*0.509^2)/(2*9.81*0.1)`

hf = 0.9903 m

so total friction is 0.9903 m