IAPWS water reference

This is the IAPWS (International Association for the Properties of Water and Steam) reference equation for water (so-called IAPWS-95 formulation).

The EOS is a Wagner–Setzmann type equation. Its form and the values of its (more than 50!) parameters were optimized for water. The EOS cannot be used for other substances.

The EOS is valid in the whole stable fluid range from the triple point up to 1000 K and 600 MPa. It can possibly be used for metastable states; the behaviour for densities between the spinodal states (at subcritical temperatures) is erratic.

adjustable parameters: 0

[1] W. Wagner and A. Pruß, J. Phys. Chem. Ref. Data 31 (2002) 387–535.

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