# How can I get properties like enthalpy and specific volume given pressure greater than 3MPa for a Rankine Cycle using R134a as the working fluid?

I have been working on a Rankine Organic Cycle (ORC), and I have to define the properties (enthalpy and specific volumen) in a certain line. I have that s = 0.324305 KJ/kgK and P = 3975.1 KPa. Given those two intensive properties I should be able to find the other ones in the thermodynamics table for R134a. But to my surprise the table for pressure gets only to 3000 KPa and I am stuck trying to find out the enthalpy and specific volume. I don't think it's proper to make aproximations since I do not know the phase of the fluid. I am just getting started in thermodynamics so I will appreciate no advanced methods or advanced mathematical analysis.

• The critical pressure of R134-a is 4060 kPa, so you are seeking thermo properties that are close to that critical pressure. Refrigerants are designed to operate well below their critical pressure, so very few researchers would attempt to get data in the range you are interested in. Commented Mar 26, 2022 at 15:42
• Thanks, I will consider looking for properties close to the critical pressure.
– Gabo
Commented Mar 26, 2022 at 20:32