STEAM – Steam and water properties

Block SymbolLicensing group: STANDARD
PIC

Function Description
The STEAM block calculates the thermodynamic properties of water and steam based on their other properties. The calculation is based on the IAPWS IF-97 standard (see http://www.iapws.org/relguide/IF97-Rev.pdf for more details). The units of temperature and pressure are defined by the parameter tunit and punit respectively; energy is in kilojoules (as it is used in IF-97 and by engineers), other properties use SI units. The function expressed by the block is defined by the func parameter. The parameter has the form <output property>_<1th input property><2nd input property> where properties is one of:

  • T - Temperature
  • p - Pressure
  • h - Enthalpy [kJ/kg]
  • v - Specific volume [m3/kg]
  • rho - Density [kg/m3]
  • s - Specific entropy
  • u - Specific internal energy [kJ/kg]
  • Cp - Specific isobaric heat capacity [kJ/kg/K]
  • Cv - Specific isochoric heat capacity [kJ/kg/K]
  • w - Speed of sound [m/s]
  • my - Viscosity
  • tc - Thermal Conductivity
  • st - Surface Tension
  • x - Vapour fraction
  • vx - Vapour Volume Fraction

The output property can have attribute:

  • sat - saturated value, i.e. for situation when water (liquid) is changed into steam (vapour)
  • V - steam (vapour) for saturated conditions
  • L - water (liquid) for saturated conditions

Examples:

  • h_pT output is enthalpy for given pressure (1st input) and temperature (2nd input)
  • Tsat_p saturated temperature (i.e. boiling temperature) for given pressure (1st input)
  • hL_p enthalpy of (liquid) water for saturated conditions given by pressure (1st input)

Inputs

u1

1st input property

Double (F64)

u2

2nd input property (if required)

Double (F64)

Parameters

func

Calculated function  1

Long (I32)

punit

Pressure unit  1

Long (I32)

1 ....

MPa

2 ....

bar

3 ....

kPa

tunit

Temperature unit  1

Long (I32)

1 ....

K

2 ....

C

Outputs

y

Output property

Double (F64)

E

Error flag

Bool

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