Estimating density of supercritical carbon dioxide and methane using modified thermodynamic models

Since the density is an important thermodynamic property of the fluid in the wide field of experimental and theoretical studies, in this work, the density of CO₂ and CH₄, as prominent supercritical fluids in industrial processes was investigated. To that end, five equation of state (EOS) models were used to estimate density of aforementioned. Deviation of each EOS models is validated and then they were modified to achieve lower errors in density prediction. Accordingly, their adjusted correlations reduced the average absolute errors to lower than 5.6%.