wall.gms : Chemical Equilibrium Problem
A Sample Nonlinear system to solve Chemical Equilibrium models.
Reference:
- Wall, T W, Greening, D, and Woolsey, R E D, Solving Complex Chemical Equilibria Using a Geometric-Programming Based Technique. Operations Research 34, 3 (1987).
Small Model of Type: NLP
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$Title Chemical Equilibrium Problem (WALL,SEQ=76)
$Ontext
A Sample Nonlinear system to solve Chemical Equilibrium models.
Wall, T W, Greening, D, and Woolsey, R E D, Solving Complex Chemical
Equilibria Using a Geometric-Programming Based Technique. OR 34, 3 (1987).
$Offtext
Variables ba, so4, baoh, oh, hso4, h ;
Equations r1, r2, r3, r4, b1, b2 ;
* scaling in powers of 10: ba -5, so4 -5, baoh -12, oh -7, hso4 -10, h -7
r1.. ba * so4 =e= 1 ;
r2.. baoh / ba / oh =e= 4.8 ;
r3.. hso4 / so4 / h =e= .98 ;
r4.. h * oh =e= 1 ;
b1.. ba + 1e-7*baoh =e= so4 + 1e-5*hso4 ;
b2.. 2 * ba + 1e-7*baoh + 1e-2*h =e= 2 * so4 + 1e-5*hso4 + 1e-2*oh ;
Model wall / all / ;
ba.l=1; so4.l=1; baoh.l=1; oh.l=1; hso4.l=1; h.l=1;
Solve wall using nlp minimizing ba;
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