Liquid density calculation methods

You can select a liquid density calculation method only for Compositional fluids that contain a liquid phase. Use the Liquid Density list in the Fluid Editor to specify the liquid density calculation method.

Equations of state

• GERG-2008 equation of state

  Important: The GERG-2008 equation of state (EOS) in AVEVA Process Simulation is currently in an experimental state.

• PR — Peng-Robinson equation of state

• SRK — Soave-Redlich-Kwong equation of state

You can use the PR and SRK equations of state as your liquid density calculation method only if you also use them as your system calculation method. To use either the PR or SRK equations of state as your liquid density calculation method, in the System list, select the equation of state, and then in the Liquid Density list, select Use system method.

When you select the GERG-2008 EOS as the liquid density calculation method, the software also uses the GERG-2008 EOS to calculate the vapor density.

In general, equations of state are not good at predicting liquid density. You may want to use a more suitable method to calculate liquid density.

Generalized methods

• COSTALD method

• Library correlations

• Rackett method

Special data packages

• API — American Petroleum Institute liquid density