PengRobinson Equation of State
PengRobinson equation of state is a widely used thermodynamic model for describing the behavior of fluids, especially gases and liquids. The PengRobinson equation is an improvement over the Van der Waals equation and aims to provide a more accurate representation of real fluid behavior, particularly for nonideal gases and liquids.
PengRobinson Equation of State


\( p = (R \; T \;/\; V  b )  [\; a \;/\; V \; (V + b ) + b \; (V  b )\; ] \)  
Symbol  English  Metric 
\( p \) = pressure of fluid  \(lbf \;/\; in^2\)  \(Pa\) 
\( R \) = universal gas constant  \(lbfft\;/\;lbmolR\)  \(J\;/\;kmolK\) 
\( T \) = temperature  \(F\)  \(K\) 
\( V \) = molar volume of fluid  \(in^3\)  \(mm^3\) 
\( b \) = parameters specific to the fluid, known as the PengRobinson parameters  \(in^3\)  \(mm^3\) 
\( a \) = parameters specific to the fluid, known as the PengRobinson parameters     