EQUATIONS OF STATE VALID CONTINUOUSLY FROM ZERO TO EXTREME PRESSURES WITH H2O AND CO2 AS EXAMPLES

A new form of equation of state is proposed for use over extremely wid e ranges of pressure where conventional equations fail. In particular, fluids, including H2O and CO2 as well as argon, etc., remain more com pressible at very high densities than can be represented by typical eq uations with van der Waals or Carnahan and Starling repulsive terms. T he new equation is fitted to the data for H2O and CO2 over the entire range from the vapor and liquid below the critical temperature to at l east 2000 K and from zero pressure to more than 10(5) bar (10 GPa) wit h good agreement. The extension of the equation for mixed fluids is di scussed.