Fluid Property Information
EES provides built-in property data for the fluids listed below. The fluids are grouped into Real Fluids, Ideal Gases, Solutions, Incompressible Substances, and Mixtures (modeled as pseudo-pure substances). Property data for air-water mixtures (psychrometrics) are provided by fluid AirH2O. Thermophysical property data for hundreds of materials are also available in the Incompressible Substances and NASA libraries.
------------------------------- REAL FLUIDS -------------------------------- ---------- MIXTURES -----------
Argon Methane R13I1 R404A R508B
Benzene Methanol R14 R407A* R511A*
Butene n-Butane R22 R407C R512A
Carbondioxide n-Decane R23 R407H* R513A
Carbonmonoxide n-Docosane R32 R410A R513B*
CarbonylSulfide n-Dodecane R40 R417A R514A
Chlorine n-Heptane R41 R422B* R515A
Chloroethene n-Hexadecane R113 R422D* R515B*
Cis-2-Butene n-Hexane R114 R423A* R516A*
Cyclohexane n-Octane R115 R424A*
Cyclopentane n-Nonane R116 R427A*
DeuteriumOxide Neopentane R134a R441A*
DiethylEther Nitrogen R141b R444A*
DimethylCarbonate NitrogenTrifluoride R142b R444B*
DimethylEther NitrousOxide R143a R448A
Ethylbenzene orthoHydrogen R152a R452A
EthyleneOxide p-Xylene R218 R453A*
Fluorine paraHydrogen R227ea R454A
Helium Potassium* R236ea R454B
HFE7000 Propylene R245ca R455A*
Hydrogen PropyleneGlycol R245fa R456A*
HydrogenChloride Propyne R290 R457A*
HydrogenSulfide SES36 R365mfc R460A*
Isobutene Steam_IAPWS R717 R465A*
Isohexane Steam_NBS R718 R466A
Isooctane SulfurDioxide R744 R469A*
Isopentane SulfurHexafluoride R1123 R470A*
Isopropanol THF R1130(E) R470B*
Krypton Toluene R1132(A) R471A*
m-Xylene trans-2-butene R1132(E) R472A*
FLD files* *Professional license only
----- IDEAL GASES ----- ------ SOLUTIONS ------ ------ INCOMPRESSIBLE ------
Air CACL2 (Calcium Chloride-Water) The Function Information dialog displays the
AirH2O EA (Ethylene Alcohol-Water) materials in the Incompressible Substances.
Ar EG (Ethylene Glycol-Water) library.
CH4 K2CO3 (Potassium Carbonate-Water) Specific heat, enthalpy and entropy data are
C2H2 KAC (Potassium Acetate-Water) available for condensed substances in the
C2H4 KFO (Potassium Formate-Water) NASA database.
C2H6 LICL (Lithium Chloride-Water)
C2H5OH MA (Methyl Alcohol-Water) NASA_EES procedure
C3H8 MGCL2 (Magnesium Chloride-Water)
C4H10 NACL (Sodium Chloride-Water)
C6H14 PG (Propylene Glycol-Water)
----- Additional Property Data -----
LiCl-Water and LiBr-Water properties
The fluid properties are of three distinct types: ideal gas, real fluid/mixtures and solutions/incompressible. The enthalpy and internal energy of ideal gas substances are dependent only upon temperature. EES will not accept pressure, along with temperature, as an independent property input in the Enthalpy and IntEnergy functions for ideal gas substances. A general rule is that substances having a name that is a chemical formula, e.g., N2 or CO2, are implemented to be ideal gases whereas real fluids use spelled-out names, e.g., Nitrogen and CarbonDioxide. Air and AirH2O (psychrometric relations) are exceptions to this rule in that both are based on ideal gas behavior. Whenever a chemical symbol notation (e.g., Ar, N2, CO2, CH4 etc.) is used, the substance is modeled as an ideal gas and the enthalpy and entropy values are based on JANAF table references. The JANAF table reference for enthalpy is based on the elements having an enthalpy value of 0 at 298K (537R). The entropy of these substances is based on the Third Law of Thermodynamics.
Whenever the substance name is spelled out (e.g., Argon, Steam (or Water or R718), Nitrogen, R12, CarbonDioxide, Methane, etc.) the substance is modeled as a real fluid with subcooled, saturated, and superheated phases. Most of the real fluids and mixtures in the table above employ a high accuracy equation of state that accurately provides property information at all conditions including the vicinity of the critical point and the subcooled region. Specific references to the equation of state are provided for each fluid. A few fluids use the Martin-Hou equation of state (A.I.Ch.E. Journal, Vol. 1, No. 2, 1955, pp. 142-151) and assume the fluid is incompressible. The Martin-Hou equation of state has a claimed accuracy of 1% in specific volume for conditions at which the density is less than 1.5 * Critical density. Thermodynamic properties at densities greater than 1.5 * critical density or in the vicinity of the critical point may be inaccurate with the Martin-Hou equation of state.
Solutions refer to a liquid or solid dissolved in water. Most of the properties for solutions require the temperature and mass concentration of the solute in %.
NH3H2O (ammonia-water) is a mixture. It requires 3 independent properties. The property designators are the same as for pure fluids with the following two differences. X designates mass fraction. Q designates quality.
Starting with version 10.364, the property keywords Water, Steam, R718 and Steam_IAPWS are treated identically. All four keywords provided access to property correlations use the Steam_IAPWS property correlations, which provide the most accurate property data for water substance and it is the current international standard. Steam_NBS and Ice use the property correlations published by Harr, Gallagher, and Kell (Hemisphere, 1984).These property correlations were the basis of the international standard for water before 1995.
Starting with version 10.627, EES can read .FDL files used with the NIST REFPROP program, which extends the number of pure fluids for which EES can provide property information.