Absolute Pressure

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

A pressure at absolute zero, abbreviated as \(p_a\), can only exist in a total vacuum and any pressure above this is called absolute pressure.  Absolute pressure is the amount by which the measured pressure exceeds a perfect vacuum.  It is specified as psia.  Absolute pressure is equal to 0 psia or -14.7 psig.

 

absolute pressure calculator

 

 

absolute pressure formulas

\(\large{ p_a = p_g  +  p_{atm} }\) 
\(\large{ p_a = p_g  +  p_v }\) 

Where:

 Units English SI
\(\large{ p_a }\) = absolute pressure \(\large{\frac{lbf}{in^2}}\) \(\large{Pa}\)
\(\large{ p_g }\) = gauge pressure \(\large{\frac{lbf}{in^2}}\) \(\large{Pa}\)
\(\large{ p_{atm} }\) = atmospheric pressure \(\large{\frac{lbf}{in^2}}\) \(\large{Pa}\)
\(\large{ p_v }\) = vacuum pressure \(\large{\frac{lbf}{in^2}}\) \(\large{Pa}\)

 

 

 

Tags: Equations for Pressure Calculators