Aerodynamic calculation
Pressure loss calculation for a duct network
Run 1
Fitting losses
No items
Velocity0.00 m/s
Specific loss0.00 Pa/m
ΔP friction0.0 Pa
ΔP total0.0 Pa
Results
Results
Runs1
Total length5.0 m
Max flow1000 m³/h
Friction losses0.0 Pa
Fitting losses0.0 Pa
TOTAL (with a 10 % margin)0.0 Pa
Calculation method
The method is set out in SP 60.13330.2020 and Idelchik's handbook of hydraulic resistance.
- Friction losses: are computed from the Altshul formula, allowing for the roughness of the duct material.
- Fitting loss coefficients: losses across fittings (bends, tees, reducers) are the sum of the loss coefficients multiplied by the velocity pressure.
Tip: Keep velocities at 4–6 m/s in main ducts and 3–4 m/s in branches. That balances noise against duct size.
The results give the total fan pressure including a 10 % margin for unaccounted losses and leakage.