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Air Ducts - Friction Loss Diagram

A major friction loss diagram for air ducts - SI units.

Friction loss in standard air ducts:

air ducts - pressure loss vs- air flow chart - m3/s. m/s, mmDownload and print Air Duct Pressure Loss vs. Air Flow and Duct Dimension Chart

  • 1 m/s = 196.85 ft/min
  • 1 m3/s = 3600 m3/h = 1000 dm3(liter)/s = 35.32 ft3/s = 2118.9 ft3/min = 13200 (UK)/min = 15852 gal (US)/min
  • 1 mm H2O = 9.81 Pa = 9.807x10-6 N/mm2 = 0.0987 10-3 bar = 1 kp/m2 = 0.09678 10-3 atm = 1.422 10-3 psi (lbf/in2)

Example - Air Duct and Friction Loss

As indicated in the diagram above, the friction loss in a 500 mm main duct with air flow 1 m3/s  - in a comfort system with air velocity limited to 5 m/s - can be estimated to 0.55 Pa/m (0.055 mm H2O/m).

Related Topics

  • Ventilation Systems

    Design of systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more.

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