Volumetric Flow Rate

The volumetric flow rate of a system is a measure of the volume of fluid passing a point in the system per unit time. The volumetric flow rate can be calculated as the product of the cross sectional area (A) for flow and average flow velocity (v).

Q = A . v . cos θ

In the special case where the flow is perpendicular to the area A, that is, θ = 0, the volumetric flow rate is:

Q = A . v

If area is measured in square feet and velocity in feet per second, equations above result in volumetric flow rate measured in cubic feet per second. Other common units for volumetric flow rate include gallons per minute, cubic centimeters per second, liter per minute, and gallons per hour.