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PropPlot (Macro Command)

 

The PropPlot command has the following format:

 

PropPlot FluidName, PlotType N1 P1 P2 .. P_N1 N2 Q1 Q2 .. Q_N2 DoQLines TMin=Tmin TMax=Tmax PMin=Pmin PMax=Pmax

 

where

    FluidName is any ideal gas or real gas property name.  Append /EESREFPROP if the property values are to be obtained from the EES_REFPROP interface.

    PlotType is anyone of the following:  TS, TV, TH, TRho, PV,  PH, HS, TP, or PSY.  (PSY is only applicable to AIRH2O;  HS is not available for EES_REFPROP fluids.}

    N1 is the number (<=6) of constant property lines in the first group of properties.  The first group is for constant pressure for TS, TH, TV and TRho and constant temperature for PV and PH.

    P1..P_N1 are the N1 values of the constant property in group 1

    N2 is the number (<=6) of constant property lines in the second group of properties, which  is usually specific entropy except for the TS plot for which it is specific volume. (N2 should be 0 for EES_REFPROP fluids)

    Q1..Q_N2 are the N2 values of the constant property in group 2

    DoQLines, TMin, TMax, PMin and PMax are optional.  

         DoQLines will draw lines of constant quality on the plot.

         TMin and TMax are the minimum and maximum values of temperature for TS, TV, TH, and TRho plots.  

         PMin and PMax are the minimum and maximum values of pressure for PV and PH plots drawn for EES_REFROP fluids.

 

Note that the property values are provided in the specified EES unit system.  See the  $ConvertEESREFROPUnits directive for EES_REFPROP fluids .

 

The $RunMacroBefore directive provides a convenient way to construct the plot before solving the equations.  Then additional plots can be superimposed on the property plot.

 

The examples below assume that the unit system has been set with $UnitSystem directive of with the Units macro command as follow  

Units SI C kPa Mass

 

Example 1

Create a TS property plot for Steam.  Include 5 constant pressure lines and 6 constant entropy lines at the specified values and draw lines of constant quality.  Note that the values for the constant pressure and constant entropy lines can be set with previously defined variables as well as with numerical values. 

 

PropPlot Steam_IAPWS TS 5 11000 5300 2100 660 299 5 0.075 1 3.5 12 50 DoQLines  TMax=600

 

 

Example 2

The TS, TV and Trho plots provide an option to display lines of constant enthalpy instead of lines of constant volume (on TS plots) or entropy (on TV and Trho) plots.  To display lines of constant enthalpy, follow the number of constant enthalpy lines (in the second grouping) with an H, as in the following example.

 

Create a TS property plot for Steam_IAPWS.  Include 4 constant pressure lines and 6 constant enthalpy lines at the specified values and draw lines of constant quality.  Note that the values for the constant pressure and constant enthalpy lines can be set with previously defined variables as well as with numerical values. 

 

PropPlot Steam_IAPWS TS 6 20000 7000 3000 800 200 20 6H 1740 2120 2500 2870 3250 3630 DoQLines

 

 

Example 3

Create a Psychrometric chart with wetbulb lines of 10, 15, 20, 35, 30, 35 C and specific volume lines of 0.8, 0.85, 0.90, and 0.95 m3/kg at a total pressure of 101 kPa in Mollier form.  The P=101.3 and Mollier are optional.  Note that the values of  wetbult and specific volume can be specified using previously defined variables.

 

PropPlot AirH2O PSY 6 10 15 20 25 30 35 4 0.8 0.85 0.9 095  P=101.3  Mollier

 

 

Example 4

The following example illustrates the use of the PropPlot macro using property data from REFPROP.  This capability requires the EES_REFPROP interface.  Create a PH property plot for propane using REFPROP data through the EES_REFPROP interface.  Include 4 constant temperature lines and draw lines of constant quality   Limit the state used in the plot to pressures between 10 and 1e5 kPa.  Note that the 0 before DoQLines is required. 

 

PropPlot propane/EESREFPROP PH 4 330 300 260 220  0 DoQLines PMin=10  PMax=1e5

 

 

Example 5

The following example illustrates the use of the PropPlot macro using property data from REFPROP.  This capability requires the EES_REFPROP interface  The $ConvertEESREFPROPUnits directive must appear in the EES program before running this example.  Create a TS property plot for R459A using REFPROP data through the EES_REFPROP interface.  Include 6 constant pressure lines and draw lines of constant quality.

 

PropPlot R459A/EESREFPROP TS 6 0.2 10 100 500 1500 3500 0 DoQLines

 

MacroCommands