Question

Assume we have 3 states of saturated vapor R-134a at +40°C, 0 °C and -40°C. Calculate the specific volume at the set of temperatures and corresponding saturated pressure assuming ideal gas behavior. Find the percent relative error = 100(v - vg)/vg with vg from the saturated R-134a table.

Answer 1

R-134a. Table values Psat, vg(T)

Ideal gas constant RR-134a = 0.08149 kJ/kg K

| T | Psat , kPa | vg | vID.G. = RT / Psat | error % |
| -40°C | 51.8 | 0.35696 | 0.36678 | 2.75 |
| 0°C | 294 | 0.06919 | 0.07571 | 9.4 |
| 40°C | 1017 | 0.02002 | 0.02509 | 25.3 |