STEAM – Steam and water properties

Block SymbolLicensing group: STANDARD

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)

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