# Mass Flow Rate

Written by Jerry Ratzlaff on . Posted in Fluid Mechanics

Mass flow rate is the average velocity of an areas density for flow.

## formula

$$\dot m_f = \rho v A$$

Where:

$$\dot m_f$$ = mass flow rate

$$\rho$$ (Greek symbol rho) = fluid density

$$v$$ = velocity

$$A$$ = area

$$Q$$ = volumetric flow rate

$$d_i$$ = internal pipe diameter

$$\pi$$ = Pi

Solve for:

$$d_i = \sqrt { \frac { 4 Q } { \pi v} }$$

$$d_i = \sqrt { \frac { 4 \dot m_f} { \pi \rho v} }$$