Pipe friction & head loss worksheet with answers

Free printable Pipe friction & head loss worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
V = 1.5 m/sD = 50 mmρ = 850 kg/m³, μ = 0.005 Pa·s

Light fuel oil (ρ = 850 kg/m³, μ = 0.005 Pa·s) flows at 1.5 m/s through a pipe with an inside diameter of 50 mm. Find the Reynolds number Re.

ρ = 850 kg/m³μ = 0.005 Pa·sV = 1.5 m/sD = 50 mm
Re =
2.Easy
V = 1.25 m/sD = 200 mmρ = 891 kg/m³, μ = 0.29 Pa·s

SAE 30 motor oil (ρ = 891 kg/m³, μ = 0.29 Pa·s) flows at 1.25 m/s through a pipe with an inside diameter of 200 mm. Find the Reynolds number Re.

ρ = 891 kg/m³μ = 0.29 Pa·sV = 1.25 m/sD = 200 mm
Re =
3.Medium
V = 2 m/sD = 300 mmL = 150 mf = 0.03

Water flows at a mean velocity of 2 m/s through a pipe 150 m long with an inside diameter of 300 mm. Use the Darcy friction factor f = 0.03 and g = 9.81 m/s². Find the friction head loss hf.

V = 2 m/sL = 150 mD = 300 mmf = 0.03g = 9.81 m/s²
hf = m
4.Medium
V = 1.1 m/sD = 100 mmL = 1000 mf = 0.015

Water flows at a mean velocity of 1.1 m/s through a pipe 1000 m long with an inside diameter of 100 mm. Use the Darcy friction factor f = 0.015 and g = 9.81 m/s². Find the friction head loss hf.

V = 1.1 m/sL = 1000 mD = 100 mmf = 0.015g = 9.81 m/s²
hf = m
5.Hard
K = 2Δz = 26 mL = 200 m, D = 250 mm, f = 0.0153× bend (K = 0.3)

Two open reservoirs are joined by a pipe 200 m long with an inside diameter of 250 mm and a Darcy friction factor f = 0.015. The water surface of the upper reservoir is 26 m above that of the lower one. The minor losses are a square-edged entrance (K = 0.5), 3 bends (K = 0.3 each), a valve (K = 2) and the exit into the lower reservoir (K = 1.0). Use g = 9.81 m/s². Find the flow rate Q in L/s.

Δz = 26 mL = 200 mD = 250 mmf = 0.015Kentrance = 0.5Kbend = 0.3 (×3)Kvalve = 2Kexit = 1.0
Q = L/s
6.Hard
K = 5free outletH = ?L = 200 m, D = 250 mm, f = 0.0252× bend (K = 0.3)

A pipe 200 m long with an inside diameter of 250 mm (Darcy friction factor f = 0.025) runs from an open reservoir and discharges as a free jet into the air. The minor losses are a square-edged entrance (K = 0.5), 2 bends (K = 0.3 each) and a valve (K = 5). Use g = 9.81 m/s². How far H must the reservoir surface be above the pipe outlet for a flow rate of 75 L/s?

Q = 75 L/sL = 200 mD = 250 mmf = 0.025Kentrance = 0.5Kbend = 0.3 (×2)Kvalve = 5
H = m

Answer key

  1. 1. Re = 12750
  2. 2. Re = 768.1
  3. 3. hf = 3.058 m
  4. 4. hf = 9.251 m
  5. 5. Q = 273.8 L/s
  6. 6. H = 3.224 m

Full step-by-step solutions: practise this topic on examproblems.com.