Air Duct Velocity Calculator

The duct velocity and air flow calculation will be able to quickly and easily determine the velocity of the air in a ducted system, allowing you to make informed decisions when designing and installing an HVAC system.
CalculationInputs﻿﻿Duct Area
:0.25 m^2​
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﻿﻿Volumetric Flow Rate
:951019 gph​
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Output﻿﻿Velocity 
:4.0 m / s​
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ExplanationAir duct velocity is the speed at which air moves through an air duct. It is usually measured in feet per minute (fpm) or meters per second (m/s). The following equation calculates the velocity of air in a duct based on the volumetric flow rate and the cross-sectional area of the duct. 
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It can be modelled with this equation:
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=V˙A = \frac {\dot{V}}{A}=AV˙​
Where:
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v=Velocity of air in a duct (ms−1)V˙=Volumetric flow rate (m3s−1)A=Duct cross−sectional area (m2)v = Velocity  \: of \: air \: in \: a \: duct \: (ms^{-1})                 \\  \dot{V} = Volumetric \: flow \: rate \: (m^3s^{-1})                    \\   A = Duct \: cross-sectional \: area \: (m^2)v=Velocityofairinaduct(ms−1)V˙=Volumetricflowrate(m3s−1)A=Ductcross−sectionalarea(m2)
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