# Example 26(a) - Solution of DAE system
# Initial Bubble Point.
# Verified Solution: Tbp = 95.5851
# Ref.: Comput. Appl. Eng. Educ. 6: 176, 1998
f(Tbp)=xA*PA+xB*PB-760*1.2
xA=0.6
PA=10^(6.90565-1211.033/(Tbp+220.79))
PB=10^(6.95464-1344.8/(219.482+Tbp))
xB=1-xA
yA=xA*PA/(760*1.2)
yB=xB*PB/(760*1.2)
Tbp(min)=60
Tbp(max)=120
Calculated values
| |
Variable |
Value |
f(x) |
Initial Guess |
Initial f(x) |
| 1 |
Tbp |
95.585087 |
6.1E-08 |
90 |
-1.4E02 |
| |
Variable |
Value |
Initial Value |
| 1 |
PA |
1196.2189 |
1020.9913 |
| 2 |
PB |
485.67158 |
406.73785 |
| 3 |
xA |
0.6 |
0.6 |
| 4 |
xB |
0.4 |
0.4 |
| 5 |
yA |
0.78698615 |
0.67170482 |
| 6 |
yB |
0.21301385 |
0.17839379 |
Root Finding Plot

Formatted equations
Nonlinear equations
| 1 |
f(Tbp) = xA*PA+xB*PB-760*1.2 = 0 |
Explicit equations
| 1 |
xA = 0.6 |
| 2 |
PA = 10^(6.90565-1211.033/(Tbp+220.79)) |
| 3 |
PB = 10^(6.95464-1344.8/(219.482+Tbp)) |
| 4 |
xB = 1-xA |
| 5 |
yA = xA*PA/(760*1.2) |
| 6 |
yB = xB*PB/(760*1.2) |
General Settings
| Total number of equations |
7 |
| Number of implicit equations |
1 |
| Number of explicit equations |
6 |
| Elapsed time |
0.00 sec |
| Reporting digits |
10 |
| Solution method |
safenewt |
| Max iterations |
150 |
| Tolerance F |
1E-07 |
| Tolerance X |
1E-07 |
| Tolerance min |
1E-07 |