Package BaseIF97/Basic computes the fundamental functions for the 5 regions of the steam tables as described in the standards document IF97.pdf. The code of these functions has been generated using Mathematica and the add-on packages "Format" and "Optimize" to generate highly efficient, expression-optimized C-code from a symbolic representation of the thermodynamic functions. The C-code has than been transformed into Modelica code. An important feature of this optimization was to simultaneously optimize the functions and the directional derivatives because they share many common subexpressions.
Equation from:
| Name | Description |
|---|---|
| g1 | Gibbs function for region 1: g(p,T) |
| g2 | Gibbs function for region 2: g(p,T) |
| g2metastable | Gibbs function for metastable part of region 2: g(p,T) |
| f3 | Helmholtz function for region 3: f(d,T) |
| g5 | Base function for region 5: g(p,T) |
| gibbs | Gibbs function for region 1, 2 or 5: g(p,T,region) |
| g1pitau | Derivative of g w.r.t. pi and tau |
| g2pitau | Derivative of g w.r.t. pi and tau |
| g5pitau | Derivative of g w.r.t. pi and tau |
| f3deltatau | 1st derivatives of f w.r.t. delta and tau |
| tph1 | Inverse function for region 1: T(p,h) |
| tps1 | Inverse function for region 1: T(p,s) |
| tph2 | Reverse function for region 2: T(p,h) |
| tps2a | Reverse function for region 2a: T(p,s) |
| tps2b | Reverse function for region 2b: T(p,s) |
| tps2c | Reverse function for region 2c: T(p,s) |
| tps2 | Reverse function for region 2: T(p,s) |
| tsat | Region 4 saturation temperature as a function of pressure |
| dtsatofp | Derivative of saturation temperature w.r.t. pressure |
| tsat_der | Derivative function for tsat |
| psat | Region 4 saturation pressure as a function of temperature |
| dptofT | Derivative of pressure w.r.t. temperature along the saturation pressure curve |
| psat_der | Derivative function for psat |
| p1_hs | Pressure as a function of enthalpy and entropy in region 1 |
| h2ab_s | Boundary between regions 2a and 2b |
| p2a_hs | Pressure as a function of enthalpy and entropy in subregion 2a |
| p2b_hs | Pressure as a function of enthalpy and entropy in subregion 2a |
| p2c_hs | Pressure as a function of enthalpy and entropy in subregion 2c |
| h3ab_p | Region 3 a b boundary for pressure/enthalpy |
| T3a_ph | Region 3 a: inverse function T(p,h) |
| T3b_ph | Region 3 b: inverse function T(p,h) |
| v3a_ph | Region 3 a: inverse function v(p,h) |
| v3b_ph | Region 3 b: inverse function v(p,h) |
| T3a_ps | Region 3 a: inverse function T(p,s) |
| T3b_ps | Region 3 b: inverse function T(p,s) |
| v3a_ps | Region 3 a: inverse function v(p,s) |
| v3b_ps | Region 3 b: inverse function v(p,s) |