Thermal Processes - Point and Path Functions, Intensive and Extensive Properties

Example 2.7:  A gas is compressed adiabatically from 1 atm and 70 °F to 5 atm.  Given the following information, find point and path functions.

k = 1.6, C_P = 4.9675 Btu/(lbmol·°R), C_V = 2.98 Btu/(lbmol·°R), R = 0.73 (atm·ft³)/(lbmol·°R) = 1.987 Btu/(lbmol·°R)

Solution:

Final temperature, T₂ (Equation 2.26):

Internal energy change, ΔU (Equation 2.22):

Adiabatic process, Q_rev = 0

Work, W_rev (Equation 2.21):

Enthalpy change, ΔH (Equation 2.24)

Initial volume, V₁ (Equation 2.1):

Final volume, V₂ (Equation 2.27)

ΔS_rev= 0

Module:

p1		(Initial pressure, Pa)
p2		(Final pressure, Pa)
T1		(Initial temperature, deg K)
T2		(Final temperature, deg K)
cp		(Specific heat at constant pressure, joules per mole per deg K)
cv		(Specific heat at constant volume, joules per mole per deg K)
n		(polytropic index of compression)
k		(adiabatic index of compression)

adiabatic or Insulated polytropic isothermal (Constant Temperature) isobaric (Constant Pressure) isochoric (Constant Volume)