Duct Velocity Calculator

Duct Velocity Calculator:

Enter the values of Air Flow Rate, CFM and Cross-sectional Area of the duct, A_(ft2) to determine the value of velocity, V_(fpm).

Enter Air Flow Rate :		CFM
Enter Cross-Sectional Area :		ft2
Result – Velocity :		fpm

Duct Velocity Formula:

Duct velocity is used to calculate the velocity of air flow within a duct, which is crucial for ensuring efficient heating, ventilation, and air conditioning (HVAC) system operation.

Velocity, V_(fpm) in feet per minute is calculated by dividing the Air Flow Rate, CFM cubic feet per minute by the Cross-sectional Area of the duct, A_(ft2) in square feet.

Velocity, V_(fpm) = CFM / A_(ft2)

V_(fpm) = velocity in feet per minute, fpm.

CFM = air flow rate in cubic feet per minute, CFM.

A_(ft2) = cross-sectional area in square feet, ft².

Duct Velocity Calculation:

1.Suppose an HVAC system is designed to deliver 1200 cubic feet per minute of air. If the duct through which this air flows has a cross-sectional area of 2 square feet, calculate the velocity of air through the duct.

Given: CFM = 1200CFM, A_(ft2) = 2ft².

Velocity, V_(fpm) = CFM / A_(ft2)

V_(fpm) = 1200 / 2

V_(fpm) = 600fpm.

2.Suppose you have an air duct that delivers 1800 cubic feet of air per minute at a velocity of 600 feet per minute. Calculate the cross-sectional area of the duct.

Given: CFM = 1800CFM, V_(fpm) = 600fpm.

Velocity, V_(fpm) = CFM / A_(ft2)

A_(ft2) = CFM / V_(fpm)

A_(ft2) = 1800 / 600

A_(ft2) =3ft².