Equations:
T
- - - - - - -
- - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - -
=
T 0
2
+
k 1
–
A
1
⎛
- - - - - -
- - - - -
- - - - - - - - - - - -
=
⎝
A t
M
k 1
Example:
Given: k=2, M=.9, T0=26.85_ C, T=373.15_K, 0=100_kg/m^3, P0=100_kPa, A=1_cm^2.
Solution: P=464.1152_kPa, At=0.9928_cm^2, =215.4333_kg/m^3.
Real Gas Law (5, 6)
These equations adapt the ideal gas law to emulate real-gas behavior. (See "ZFACTOR" in Chapter 3.)
Equations:
P V
=
n Z R T
Example:
Given: Pc=48_atm, Tc=298_K, P=5_kPa, V=10_1, MW=64_g/gmol, T=75_ C.
Solution: n=0.0173_gmol, m=1.1057E–3_kg.
Real Gas State Change (5, 7)
This equation adapts the ideal gas state-change equation to emulate real-gas behavior. (See "ZFACTOR" in
Chapter 3.)
Equation:
Example:
Given: Pc=48_atm, Pi=100_kPa, Pf=50_kPa, Ti=75_ C, Tc=298_K, Vi=10_1, Tf=250_ C.
(Remember Zf and Zi are automatically calculated using these variables)
Solution: Vf=30.1703_l.
2
P
T
⎛
⎞
- ---- -
------ -
=
⎝
⎠
2
P0
T0
M
1
- - - -------- -
k 1
–
T
⎛
⎞
- - - - - - -
- - - - - - -
=
⎝
⎠
0
T 0
k
+
1
----------------------- -
2
k 1
–
2
k 1
–
⎛
⎞
⎞
2
- - - - - - - - - - - -
1
+
M
⎝
⎠
⎠
+
2
m
=
n MW
Pf Vf
Pi Vi
----------------
--------------- -
=
Zf Tf
Zi Ti
k
----------- -
k 1
–
Equation Reference 5-27