This package provides high accuracy physical properties for water according to the IAPWS/IF97 standard. It has been part of the ThermoFluid Modelica library and been extended, reorganized and documented to become part of the Modelica Standard library.

An important feature that distinguishes this implementation of the IF97 steam property standard is that this implementation has been explicitly designed to work well in dynamic simulations. Computational performance has been of high importance. This means that there often exist several ways to get the same result from different functions if one of the functions is called often but can be optimized for that purpose.

The original documentation of the IAPWS/IF97 steam properties can freely be distributed with computer implementations, so for curious minds the complete standard documentation is provided with the Modelica properties library. The following documents are included (in directory Modelica/Resources/Documentation/Media/Water/IF97documentation):

- IF97.pdf The standards document for the main part of the IF97.
- Back3.pdf The backwards equations for region 3.
- crits.pdf The critical point data.
- meltsub.pdf The melting- and sublimation line formulation (in IF97_Utilities.BaseIF97.IceBoundaries)
- surf.pdf The surface tension standard definition
- thcond.pdf The thermal conductivity standard definition
- visc.pdf The viscosity standard definition

- Package
**BaseIF97**contains the implementation of the IAPWS-IF97 as described in IF97.pdf. The explicit backwards equations for region 3 from Back3.pdf are implemented as initial values for an inverse iteration of the exact function in IF97 for the input pairs (p,h) and (p,s). The low-level functions in BaseIF97 are not needed for standard simulation usage, but can be useful for experts and some special purposes. - Function
**water_ph**returns all properties needed for a dynamic control volume model and properties of general interest using pressure p and specific entropy enthalpy h as dynamic states in the record ThermoProperties_ph. - Function
**water_ps**returns all properties needed for a dynamic control volume model and properties of general interest using pressure p and specific entropy s as dynamic states in the record ThermoProperties_ps. - Function
**water_dT**returns all properties needed for a dynamic control volume model and properties of general interest using density d and temperature T as dynamic states in the record ThermoProperties_dT. - Function
**water_pT**returns all properties needed for a dynamic control volume model and properties of general interest using pressure p and temperature T as dynamic states in the record ThermoProperties_pT. Due to the coupling of pressure and temperature in the two-phase region, this model can obviously only be used for one-phase models or models treating both phases independently. - Function
**hl_p**computes the liquid specific enthalpy as a function of pressure. For overcritical pressures, the critical specific enthalpy is returned - Function
**hv_p**computes the vapour specific enthalpy as a function of pressure. For overcritical pressures, the critical specific enthalpy is returned - Function
**sl_p**computes the liquid specific entropy as a function of pressure. For overcritical pressures, the critical specific entropy is returned - Function
**sv_p**computes the vapour specific entropy as a function of pressure. For overcritical pressures, the critical specific entropy is returned - Function
**rhol_T**computes the liquid density as a function of temperature. For overcritical temperatures, the critical density is returned - Function
**rhol_T**computes the vapour density as a function of temperature. For overcritical temperatures, the critical density is returned - Function
**dynamicViscosity**computes the dynamic viscosity as a function of density and temperature. - Function
**thermalConductivity**computes the thermal conductivity as a function of density, temperature and pressure.**Important note**: Obviously only two of the three inputs are really needed, but using three inputs speeds up the computation and the three variables are known in most models anyways. The inputs d,T and p have to be consistent. - Function
**surfaceTension**computes the surface tension between vapour and liquid water as a function of temperature. - Function
**isentropicEnthalpy**computes the specific enthalpy h(p,s,phase) in all regions. The phase input is needed due to discontinuous derivatives at the phase boundary. - Function
**dynamicIsentropicEnthalpy**computes the specific enthalpy h(p,s,,dguess,Tguess,phase) in all regions. The phase input is needed due to discontinuous derivatives at the phase boundary. Tguess and dguess are initial guess values for the density and temperature consistent with p and s. This function should be preferred in dynamic simulations where good guesses are often available.

- First implemented:
*July, 2000*by Hubertus Tummescheit for the ThermoFluid Library with help from Jonas Eborn and Falko Jens Wagner - Code reorganization, enhanced documentation, additional functions:
*December, 2002*by Hubertus Tummescheit and moved to Modelica properties library.

Modelon AB

Ideon Science Park

SE-22370 Lund, Sweden

email: hubertus@modelon.se

Name | Description |
---|---|

BaseIF97 | Modelica Physical Property Model: the new industrial formulation IAPWS-IF97 |

iter | |

waterBaseProp_ph | Intermediate property record for water |

waterBaseProp_ps | Intermediate property record for water |

rho_props_ps | Density as function of pressure and specific entropy |

rho_ps | Density as function of pressure and specific entropy |

T_props_ps | Temperature as function of pressure and specific entropy |

T_ps | Temperature as function of pressure and specific entropy |

h_props_ps | Specific enthalpy as function or pressure and temperature |

h_ps | Specific enthalpy as function or pressure and temperature |

phase_ps | Phase as a function of pressure and specific entropy |

phase_ph | Phase as a function of pressure and specific enthalpy |

phase_dT | Phase as a function of pressure and temperature |

rho_props_ph | Density as function of pressure and specific enthalpy |

rho_ph | Density as function of pressure and specific enthalpy |

rho_ph_der | Derivative function of rho_ph |

T_props_ph | Temperature as function of pressure and specific enthalpy |

T_ph | Temperature as function of pressure and specific enthalpy |

T_ph_der | Derivative function of T_ph |

s_props_ph | Specific entropy as function of pressure and specific enthalpy |

s_ph | Specific entropy as function of pressure and specific enthalpy |

s_ph_der | Specific entropy as function of pressure and specific enthalpy |

cv_props_ph | Specific heat capacity at constant volume as function of pressure and specific enthalpy |

cv_ph | Specific heat capacity at constant volume as function of pressure and specific enthalpy |

regionAssertReal | Assert function for inlining |

cp_props_ph | Specific heat capacity at constant pressure as function of pressure and specific enthalpy |

cp_ph | Specific heat capacity at constant pressure as function of pressure and specific enthalpy |

beta_props_ph | Isobaric expansion coefficient as function of pressure and specific enthalpy |

beta_ph | Isobaric expansion coefficient as function of pressure and specific enthalpy |

kappa_props_ph | Isothermal compressibility factor as function of pressure and specific enthalpy |

kappa_ph | Isothermal compressibility factor as function of pressure and specific enthalpy |

velocityOfSound_props_ph | Speed of sound as function of pressure and specific enthalpy |

velocityOfSound_ph | |

isentropicExponent_props_ph | Isentropic exponent as function of pressure and specific enthalpy |

isentropicExponent_ph | Isentropic exponent as function of pressure and specific enthalpy |

ddph_props | Density derivative by pressure |

ddph | Density derivative by pressure |

ddhp_props | Density derivative by specific enthalpy |

ddhp | Density derivative by specific enthalpy |

waterBaseProp_pT | Intermediate property record for water (p and T preferred states) |

rho_props_pT | Density as function or pressure and temperature |

rho_pT | Density as function or pressure and temperature |

h_props_pT | Specific enthalpy as function or pressure and temperature |

h_pT | Specific enthalpy as function or pressure and temperature |

h_pT_der | Derivative function of h_pT |

rho_pT_der | Derivative function of rho_pT |

s_props_pT | Specific entropy as function of pressure and temperature |

s_pT | Temperature as function of pressure and temperature |

cv_props_pT | Specific heat capacity at constant volume as function of pressure and temperature |

cv_pT | Specific heat capacity at constant volume as function of pressure and temperature |

cp_props_pT | Specific heat capacity at constant pressure as function of pressure and temperature |

cp_pT | Specific heat capacity at constant pressure as function of pressure and temperature |

beta_props_pT | Isobaric expansion coefficient as function of pressure and temperature |

beta_pT | Isobaric expansion coefficient as function of pressure and temperature |

kappa_props_pT | Isothermal compressibility factor as function of pressure and temperature |

kappa_pT | Isothermal compressibility factor as function of pressure and temperature |

velocityOfSound_props_pT | Speed of sound as function of pressure and temperature |

velocityOfSound_pT | Speed of sound as function of pressure and temperature |

isentropicExponent_props_pT | Isentropic exponent as function of pressure and temperature |

isentropicExponent_pT | Isentropic exponent as function of pressure and temperature |

waterBaseProp_dT | Intermediate property record for water (d and T preferred states) |

h_props_dT | Specific enthalpy as function of density and temperature |

h_dT | Specific enthalpy as function of density and temperature |

h_dT_der | Derivative function of h_dT |

p_props_dT | Pressure as function of density and temperature |

p_dT | Pressure as function of density and temperature |

p_dT_der | Derivative function of p_dT |

s_props_dT | Specific entropy as function of density and temperature |

s_dT | Temperature as function of density and temperature |

cv_props_dT | Specific heat capacity at constant volume as function of density and temperature |

cv_dT | Specific heat capacity at constant volume as function of density and temperature |

cp_props_dT | Specific heat capacity at constant pressure as function of density and temperature |

cp_dT | Specific heat capacity at constant pressure as function of density and temperature |

beta_props_dT | Isobaric expansion coefficient as function of density and temperature |

beta_dT | Isobaric expansion coefficient as function of density and temperature |

kappa_props_dT | Isothermal compressibility factor as function of density and temperature |

kappa_dT | Isothermal compressibility factor as function of density and temperature |

velocityOfSound_props_dT | Speed of sound as function of density and temperature |

velocityOfSound_dT | Speed of sound as function of density and temperature |

isentropicExponent_props_dT | Isentropic exponent as function of density and temperature |

isentropicExponent_dT | Isentropic exponent as function of density and temperature |

hl_p | Compute the saturated liquid specific h(p) |

hv_p | Compute the saturated vapour specific h(p) |

sl_p | Compute the saturated liquid specific s(p) |

sv_p | Compute the saturated vapour specific s(p) |

rhol_T | Compute the saturated liquid d(T) |

rhov_T | Compute the saturated vapour d(T) |

rhol_p | Compute the saturated liquid d(p) |

rhov_p | Compute the saturated vapour d(p) |

dynamicViscosity | Compute eta(d,T) in the one-phase region |

thermalConductivity | Compute lambda(d,T,p) in the one-phase region |

surfaceTension | Compute sigma(T) at saturation T |

isentropicEnthalpy | Isentropic specific enthalpy from p,s (preferably use dynamicIsentropicEnthalpy in dynamic simulation!) |

isentropicEnthalpy_props | |

isentropicEnthalpy_der | Derivative of isentropic specific enthalpy from p,s |

dynamicIsentropicEnthalpy | Isentropic specific enthalpy from p,s and good guesses of d and T |

Currently the Events/noEvents switch is only implemented for p-h states. Only after testing that implementation, it will be extended to dT.

Generated at 2024-05-19T18:15:52Z by OpenModelicaOpenModelica 1.22.4 using GenerateDoc.mos