A MOLECULAR-DYNAMICS STUDY OF THE PRESSURE-VOLUME-TEMPERATURE PROPERTIES OF SUPERCRITICAL FLUIDS .1. H2O

The method of molecular dynamics (MD) is used to stimulate the pressure-volume-temperature (PVT) of water in the pressure range of 5 kbar to 1 megabar and in the temperature range of 700 to 4000 K. For the MD simulation, we use the exponential-6 form for the intermolecular potential. The parameters of the potential are calculated from the available experimental PVT data. The MD-stimulated data fit the experimental (static) and the shock-wave data well. An equation of state based on the experimental and MD-simulated data ais as follows: P = a/V + b/V2 + c/V4.586 where a = 1.40203 . 1E + 5 - 41.2336T, b = -7.72779 . 1E + 6 + 6.70124 . 1E + 3 . T, c = 6.52012 . 1E + 9 - 0.45580 . 1E + 6 . T, T in K and P in bar.