Bridgman 2nd order - Githubissues

thorade / HelmholtzMedia

Modelica library for the calculation of fluid properties from a Helmholtz energy equation of state (EoS).

BSD 3-Clause "New" or "Revised" License

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Bridgman 2nd order #20

Closed thorade closed 9 years ago

thorade commented 11 years ago

A couple of second order derivatives are calculated already, additionally it would be good to calculate the derivatives used by Bridgman for his 2nd order derivatives transformation table. These are:

(∂²v/∂p²)_T
(∂²v/∂p∂T)
(∂²v/∂T²)_p
(∂c_p/∂T)_p = (∂²h/∂T²)_p

Other base sets would be possible (and easier to calculate from an Helmholtz EoS), but these are the ones suggested by Bridgman. http://dx.doi.org/10.1103/PhysRev.3.273

thorade commented 10 years ago

The development version of RefProp calculates the following four second order derivatives:

(∂²p/∂ϱ²)_T
(∂²p/∂ϱ∂T)
(∂²p/∂T²)_ϱ
(∂²u/∂T²)_ϱ = (∂c_v/∂T)_ϱ

All other second order derivaties can be calculated from this base set! https://tubdok.tub.tuhh.de/bitstream/11420/1209/1/Thorade_2014_EntropieBewertung.pdf#section.A.2

thorade commented 9 years ago

Closing this issue, as all derivatives can be calculated from the given table A.2.