Duct airflow calculator
Aeration Fan Calculator
OSU Biosystems Engineering
Grain Bin Air Duct and Pressure Loss Calculator
This calculator estimates the static pressure in a duct system used for aeration of a grain bin.   Calculations are based on air at 60 F and standard atmospheric pressure.   If more accurate estimates are needed consult a professional engineer.  This calculator is provided as is and OSU assumes no responsibility for results obtained.
Help with this calculator

Select duct shape and enter the dimensions in inches

 inches in diameter
RoundDuct pic

 inches wide   inches deep

 inches in diameter

Enter the Length of Duct in feet:

Enter the number of each type of fitting in the boxes below:
 90 degree bends   Ball valves 
 30 or 45 degree bends   Pipe entrance 
 Couplings   Pipe exit 

Enter the flow rate in cubic feet per minute through the duct 

Calculated results:
Velocity in duct:
Reynolds number:
Reynold friction factor:
Static pressure in duct: