I want to draw ph diagram using Engineering equation solver EES for refrigerant R134a and R1234fy and some other. I don't know how to draw the multiple ph diagram on same dome or overlapping to compare
It's easy enough to do with Excel, either with the two in a single graph or one on top of the other with the area of the top graph set to transparent.
Does the latest version of NIST's REFPROP include 2,3,3,3-Tetrafluoropropene (R1234yf)? If you have the EoS in EES it's easy to copy and paste it into an Excel macro.
Dudley J Benton I don't understand, how it could be drawn when any of two refrigerants have different enthalpy's at given pressure so the dome will shift, even if I have Nist prop how do I achieve the two ph diagram
Here is one example of many for how you might create a graph. Rather than being R134a vs. R1234yf, this spreadsheet shows the difference between the older ASHRAE and newer NIST formulations for the same refrigerant (R134a). This spreadsheet only shows the vapor dome but could easily be extended to the whole domain. Here I chose to use a blue curve for ASHRAE and red circles for NIST. You could use blue curves for one and red curves for the other. The two formulations are close but not exactly the same. The differences between R134a and R1234yf would be larger. You also need to consider the reference point, which in this case was different and required a shift. ASHRAE uses Hf=0 at -40°F, whereas NIST uses Hf=0 at the boiling point at 1 atm. Many years ago I created just such a graph to show the difference between the 1967 ASME steam tables and the 1997 when applied to steam turbine performance. Some manufactures (including GE) insisted on using the 1967 properties well into the 21st century.
Dudley J Benton Well, thank you for the information and graphs. It seems pretty complex , I will try to achieve the target with the way you described
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