Volumetric Flow rate (V) of a system is a measure of the volume of fluid passing a point in the system per unit tie. The Volumetric Flow rate can be calculated as the product of the cross sectional area (A) for flow and the average flow velocity(v).
V=Av
Where :
(A) is the cross sectional area for flow
(v) is the average flow velocity.
Flow rate and velocity are related, but quite different, physical quantities. To make the distinction clear, think about the flow rate of a river. The greater the velocity of the water, the greater the flow rate of the river. But flow rate also depends on the size of the river. A rapid mountain stream carries far less water than the Amazon River in Brazil, for example. The precise relationship between flow rate Q and velocity v is
Q=Av
where A is the cross-sectional area and v is the average velocity. The relationship tells us that flow rate is directly proportional to both the magnitude of the average velocity (hereafter referred to as the speed) and the size of a river, pipe, or other conduit. The larger the conduit, the greater its cross-sectional area.
units can be cubic feet per second, gallons per minute, cubic centimeters per second ,liters per minute, and gallons per hour.
Area square feet and velocity feet per second.