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 = 2.1 m/sD = 50 mmν = 1.14 × 10⁻⁶ m²/s

Water at 15 °C (ν = 1.14 × 10⁻⁶ m²/s) flows at a mean velocity of 2.1 m/s through a pipe with an inside diameter of 50 mm. Find the Reynolds number Re.

V = 2.1 m/sD = 50 mmν = 1.14 × 10⁻⁶ m²/s
Re =
2.Easy
Q = 40 L/sD = 150 mmν = 1.00 × 10⁻⁶ m²/s

Water at 20 °C (ν = 1.00 × 10⁻⁶ m²/s) flows through a pipe with an inside diameter of 150 mm at 40 L/s. Find the Reynolds number Re.

Q = 40 L/sD = 150 mmν = 1.00 × 10⁻⁶ m²/s
Re =
3.Medium
Q = 25 L/sD = 100 mmL = 300 mf = 0.028

Water flows at 25 L/s through a pipe 300 m long with an inside diameter of 100 mm. Use the Darcy friction factor f = 0.028 and g = 9.81 m/s². Find the friction head loss hf.

Q = 25 L/sL = 300 mD = 100 mmf = 0.028g = 9.81 m/s²
hf = m
4.Medium
V = 1.9 m/sD = 100 mmL = 300 mf = 0.018

Water (ρ = 1000 kg/m³) flows at 1.9 m/s through a horizontal pipe, 300 m long, with an inside diameter of 100 mm. Use the Darcy friction factor f = 0.018 and g = 9.81 m/s². Find the pressure drop Δp over the pipe in kPa.

V = 1.9 m/sL = 300 mD = 100 mmf = 0.018ρ = 1000 kg/m³
Δp = kPa
5.Hard
K = 2Δz = 17 mL = 150 m, D = 300 mm, f = 0.0223× bend (K = 0.3)

Two open reservoirs are joined by a pipe 150 m long with an inside diameter of 300 mm and a Darcy friction factor f = 0.022. The water surface of the upper reservoir is 17 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 = 17 mL = 150 mD = 300 mmf = 0.022Kentrance = 0.5Kbend = 0.3 (×3)Kvalve = 2Kexit = 1.0
Q = L/s
6.Hard
K = 5Δz = ?L = 300 m, D = 300 mm, f = 0.0222× bend (K = 0.3)

Two open reservoirs are joined by a pipe 300 m long with an inside diameter of 300 mm and a Darcy friction factor f = 0.022. The minor losses are a square-edged entrance (K = 0.5), 2 bends (K = 0.3 each), a valve (K = 5) and the exit into the lower reservoir (K = 1.0). Use g = 9.81 m/s². What difference in water level Δz between the reservoirs gives a flow rate of 120 L/s?

Q = 120 L/sL = 300 mD = 300 mmf = 0.022Kentrance = 0.5Kbend = 0.3 (×2)Kvalve = 5Kexit = 1.0
Δz = m

Answer key

  1. 1. Re = 92105
  2. 2. Re = 339531
  3. 3. hf = 43.38 m
  4. 4. Δp = 97.47 kPa
  5. 5. Q = 329 L/s
  6. 6. Δz = 4.275 m

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