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 = 3 m/sD = 40 mmν = 1.31 × 10⁻⁶ m²/s

Water at 10 °C (ν = 1.31 × 10⁻⁶ m²/s) flows at a mean velocity of 3 m/s through a pipe with an inside diameter of 40 mm. Find the Reynolds number Re.

V = 3 m/sD = 40 mmν = 1.31 × 10⁻⁶ m²/s
Re =
2.Easy
V = 1.25 m/sD = 100 mmρ = 880 kg/m³, μ = 0.04 Pa·s

Hydraulic oil (ρ = 880 kg/m³, μ = 0.04 Pa·s) flows at 1.25 m/s through a pipe with an inside diameter of 100 mm. Find the Reynolds number Re.

ρ = 880 kg/m³μ = 0.04 Pa·sV = 1.25 m/sD = 100 mm
Re =
3.Medium
V = 2.4 m/sD = 300 mmL = 100 mf = 0.022

Water (ρ = 1000 kg/m³) flows at 2.4 m/s through a horizontal pipe, 100 m long, with an inside diameter of 300 mm. Use the Darcy friction factor f = 0.022 and g = 9.81 m/s². Find the pressure drop Δp over the pipe in kPa.

V = 2.4 m/sL = 100 mD = 300 mmf = 0.022ρ = 1000 kg/m³
Δp = kPa
4.Medium
V = 2.5 m/sD = 75 mmL = 100 mf = 0.03

Water (ρ = 1000 kg/m³) flows at 2.5 m/s through a horizontal pipe, 100 m long, with an inside diameter of 75 mm. Use the Darcy friction factor f = 0.03 and g = 9.81 m/s². Find the pressure drop Δp over the pipe in kPa.

V = 2.5 m/sL = 100 mD = 75 mmf = 0.03ρ = 1000 kg/m³
Δp = kPa
5.Hard
K = 0.2Δz = 5 mL = 400 m, D = 300 mm, f = 0.0153× bend (K = 0.3)

Two open reservoirs are joined by a pipe 400 m long with an inside diameter of 300 mm and a Darcy friction factor f = 0.015. The water surface of the upper reservoir is 5 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 = 0.2) 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 = 5 mL = 400 mD = 300 mmf = 0.015Kentrance = 0.5Kbend = 0.3 (×3)Kvalve = 0.2Kexit = 1.0
Q = L/s
6.Hard
K = 2free outletH = ?L = 300 m, D = 200 mm, f = 0.024× bend (K = 0.3)

A pipe 300 m long with an inside diameter of 200 mm (Darcy friction factor f = 0.02) 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), 4 bends (K = 0.3 each) and a valve (K = 2). 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 = 300 mD = 200 mmf = 0.02Kentrance = 0.5Kbend = 0.3 (×4)Kvalve = 2
H = m

Answer key

  1. 1. Re = 91603
  2. 2. Re = 2750
  3. 3. Δp = 21.12 kPa
  4. 4. Δp = 125 kPa
  5. 5. Q = 147.3 L/s
  6. 6. H = 10.08 m

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