# Air Pressure Loss through Piping

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

## Air Pressure Loss through Piping formula

 $$\large{ p_l = \frac { \mu \; l \; v_a{^2} \; \rho } {24 \; d \; g } }$$

### Where:

 Units English Metric $$\large{ p_l }$$ = air pressure loss $$\large{\frac{lbf}{ft^2}}$$ $$Pa$$ $$\large{ \rho }$$  (Greek symbol rho) = density of air $$\large{\frac{lbm}{ft^3}}$$ $$\large{\frac{kg}{m^3}}$$ $$\large{ \mu }$$  (Greek symbol mu) = friction coefficient of air dimensionless $$\large{ v_a }$$ = air velocity $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$ $$\large{ g }$$ = gravitational acceleration $$\large{\frac{ft}{sec^2}}$$ $$\large{\frac{m}{s^2}}$$ $$\large{ d }$$ = pipe inside diameter $$in$$ $$mm$$ $$\large{ l }$$ = length of pipe $$ft$$ $$m$$