capeOpenEquilibriumProp

Calculates one or more properties at phase equilibrium at one or more specified conditions. Both the flash constraints and the properties that can be calculated using this method are given by capeOpenFlashPropList.

Syntax

[values,...]=capeOpenEquilibriumProp(handle,props,X,prop1,val1,prop2,val2,type)

Arguments

handle: package handle, as obtained from capeOpenGetPackage

propNames: string. Multiple properties can be specified; separate the properties by a space.

X: overall composition. Number of columns must match the number of compounds. Multiple rows indicate multiple evaluation conditions. X is in mole fraction or mass fraction, depending on the current basis.

prop1: string, first constraint property. A list of valid flash constraint properties can be obtained using capeOpenFlashPropList.

val1: value for the first flash constraint property. Can be a column vector for multiple conditions. The unit of measure of the value may depend on the basis.

prop2: string, second constraint property.

val2: value for the second flash constraint property. Can be a column vector for multiple conditions. The unit of measure of the value may depend on the basis.

type: string value indicating the desired solution type. Optional. Valid values are "Unspecified" (default), and if vapor fraction is part of the flash constraints, additional valid values are "Normal" or "Retrograde".

For X, val1 and val2, multiple rows mean multiple conditions. If multiple rows are specified for X, val1 or val2, those values that have multiple rows must have the same number of rows. Those values have a single row signify a constant condition or composition.

Returns

values: column vector of values. One vector will be returned for each property. The number of values in each vector matches the number of evaluation conditions.

As opposed to other functions, this function will return partial results if some of the calculations failed. Numbers that are not known are set to NaN; if the messages are turned on (default), failed calculations will produce a message.

Example


-->handle=capeOpenGetPackage("TEA (CAPE-OPEN 1.1)","C1_C2");

-->//let's calculate and plot the phase envelope at 1 atm for this system

-->frac=0:0.05:1

 frac  =
 
 
         column  1 to 14
 
    0.    0.05    0.1    0.15    0.2    0.25    0.3    0.35    0.4    0.45    0.5    0.55    0.6    0.65  
 
         column 15 to 21
 
    0.7    0.75    0.8    0.85    0.9    0.95    1.  
 
-->X=[frac' 1-frac']

 X  =
 
    0.      1.    
    0.05    0.95  
    0.1     0.9   
    0.15    0.85  
    0.2     0.8   
    0.25    0.75  
    0.3     0.7   
    0.35    0.65  
    0.4     0.6   
    0.45    0.55  
    0.5     0.5   
    0.55    0.45  
    0.6     0.4   
    0.65    0.35  
    0.7     0.3   
    0.75    0.25  
    0.8     0.2   
    0.85    0.15  
    0.9     0.1   
    0.95    0.05  
    1.      0.    
 
-->P=101325

 P  =
 
    101325.  
 
-->tbub=capeOpenEquilibriumProp(handle,"temperature",X,"pressure",P,"vaporFraction",0)

 tbub  =
 
    184.55     
    165.12909  
    151.38884  
    142.77612  
    136.97314  
    132.74231  
    129.47314  
    126.83926  
    124.65081  
    122.78929  
    121.17652  
    119.75851  
    118.49664  
    117.36239  
    116.33417  
    115.39529  
    114.53258  
    113.73553  
    112.99557  
    112.30568  
    111.66     
 
-->tdew=capeOpenEquilibriumProp(handle,"temperature",X,"pressure",P,"vaporFraction",1)

 tdew  =
 
    184.55     
    183.62459  
    182.66089  
    181.65497  
    180.60223  
    179.49721  
    178.3334   
    177.10294  
    175.79617  
    174.4011   
    172.90252  
    171.28073  
    169.50954  
    167.55296  
    165.35949  
    162.85135  
    159.90232  
    156.28474  
    151.51303  
    144.15511  
    111.66     
 
-->plot(frac',[tdew tbub])



-->//another example: we start at T = 298.15 K and 1 atm, equimolar, and 
-->//we add 1 kJ/mol energy. We want to know the temperature increase


-->h0=capeOpenEquilibriumProp(handle,"enthalpy",[0.5 0.5],"pressure",P,"temperature",298.15)

 h0  =
 
  - 35.97927  
 
-->T1=capeOpenEquilibriumProp(handle,"temperature",[0.5 0.5],"pressure",P,"enthalpy",h0+1e3)

 T1  =
 
    320.25879