How to Calculate the CFM of a Blower


Many industrial processes require continuous aeration. Sewage treatment, for instance, uses aerobic microbes that respire constantly as they break down sludge. An industrial blower provides the necessary oxygen by maintaining a steady flow of air into the reaction chamber. You can estimate a blower's volumetric flow rate from the reactants' oxygen absorption rate. The other relevant factors are temperature and the pressure of air at the blower's discharge point.

  • Add 460 to the temperature at the discharge point, measured in degrees Fahrenheit, to convert it to degrees Rankine. If, for instance, air leaves the blower at 80 degrees: 80 + 460 = 540 degrees Rankine.

  • Multiply the Rankine temperature by the number of pounds-moles of oxygen that is transferred each minute. If, for instance, 8 pounds-moles of oxygen reach the reactants each minute: 540 x 8 = 4,320.

  • Multiply this product by 10.73, which is the gas constant: 4,320 x 10.73 = 46,354.

  • Divide the result by the pressure at the gas discharge point, measured in pounds per square inch. If this pressure, for instance, measures 15 pounds per square inch: 46,354 / 15 = approximately 3,090. This answer is the blower's volumetric flow rate, measured in cubic feet per minute.

Related Searches


  • Photo Credit Thinkstock Images/Comstock/Getty Images
Promoted By Zergnet



You May Also Like

  • What Is a Centrifugal Blower?

    Many industrial processes require the movement of air or other gas. Whenever you need a continuous flow of air or gas, centrifugal...

  • How to Calculate the CFM of a Bathroom Fan

    Bathroom fans work by recirculating air in your bathroom with outside air. These ventilating fans are necessary in windowless bathrooms because the...

  • How to Calculate Cubic Feet in an Air Duct

    Ductwork length is critical in HVAC systems because ductwork that is too long can significantly reduce the efficiency of the HVAC unit....

  • How to Calculate CFM From RPMs

    Developers of air-movement mechanisms such as fans and compressors must consider the basic relationship between fan or impeller speed in rpm (revolutions...

  • How to Calculate Air Infiltration

    Calculating the air infiltration of a building requires a complex set of operations, but the result provides keen insight into how the...

  • How to Calculate Pipe Pressure & Lift Head

    For most people, a burst pipe only happens in cold and unexpected settings, due to water freezing. However, pipes can burst for...

  • How to Calculate the CFM of Fans

    In today's modern air-conditioned houses, a proper ventilation system is very important to avoid moisture and eliminate air that can carry impurities...

  • Types of Air Blowers

    Air blowers generally use centrifugal force to propel air forward. Inside a centrifugal air blower is a wheel with small blades on...

Related Searches

Check It Out

3 Day-to-Night Outfits for the Work Week

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!