Mass Flow Rate

The Mass Flow Rate calculator computes the mass flow rate based on the total mass and total time.

INSTRUCTIONS: Choose units and enter the following:

• (m) This is the total mass
• (t) This is the total time

Mass Flow Rate (MFR): The calculator returns the mass flow rate in kilograms per second.  However this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

In physics and engineering,Mass Flow Rate is the mass of a substance which passes through a given surface per unit of time. Its unit is kilogram per second in SI units, and slug per second or pound per second in US customary units.

Sometimes, mass flow rate is termed mass flux or mass current:

         MFR = m/t

Where:

• MFR = Mass Flow Rate
• m =  mass
• t = time

Notes

There is no accumulation or destruction of mass through the tube; the same amount of mass leaves the tube as enters the tube. At any plane perpendicular to the center line of the tube, the same amount of mass passes through. We call the amount of mass passing through a plane the mass flow rate.

Since mass is a scalar quantity, the mass flow rate (the time derivative of mass) is also a scalar quantity. The change in mass is the amount that flows after crossing the boundary for some time duration, not simply the initial amount of mass at the boundary minus the final amount at the boundary, since the change in mass flowing through the area would be zero for steady flow.