Problem # p023

Approximate value of specific heats

Using the following table :

Temperature
T [°C]
Pressure
p [MPa]
Spec. Volume
v [m³/kg]
Internal Energy
u [kJ/kg]
Enthalpy
h [kJ/kg]
500.000.20000 1.7814 3131.43487.7
510.000.20000 1.8046 3148.23509.1
530.000.21000 1.7627 3181.83552.0
540.000.21000 1.7847 3198.83573.6
550.000.21000 1.8068 3215.93595.3
560.000.21000 1.8289 3233.03617.1

determine as best as possible the approximate values of :

  1. The specific heat at constant pressure of p = 0.21 MPa.



  2. The specific heat at constant volume ( use linear interpolation or at least indicate which numbers you are going to use ). The data you use have to come from different pressures.



  3. The specific gas constant (assuming we have an ideal gas).