Teneq1b

Name: Teneq1b - Chemical Equilibrium Problem - R = 40
Source: Hiebrt, K. L., ACM Trans. Math. Software 8, 1(1982)
Reference/s Bullard, L. G. and Biegler, L. T., Computers Chem. Engng. 15(4), 239 (1991).
  Shacham, M., pp. 891-923 in A. W. Westerberg and H. H. Chien (Eds),
  Proc. of FOCAPD 2, CACHE Publications, Ann Arbor, Michigan, 1984.
       
Model: 10 implicit equations, indep. variables x1 to x10
  Higher difficulty level
  Constraints: xi are nonnegative for I=1,2,…10
  Discontinuities: Undefined for negative values of x1,x2,x3,x4
  Initial estimates: 1. (2, 5, 80, 1, 0, 0, 0, 0,20, 5); 2.(1, 1, 20, 1,0, 0, 0, 0, 0, 1);
  3. (2, 5, 40, 1, 0, 0, 0, 0, 0, 5);
       
Solved by Shacham, M., POLYMATH 5.1, build 19, April 9, 2001
       
Model Eqs. Chemical Equilibrium Problem |POLVER05_1

EXCEL FILE 

f(x1) = x1+x4-3 #

TEXT FILE 

f(x2) = 2*x1+x2+x4+x7+x8+x9+2*x10-R #

POLYMATH FILE 

f(x3) = 2*x2+2*x5+x6+x7-8 #
  f(x4) = 2*x3+x5-4*R #
  f(x5) = x1*x5-0.193*x2*x4 #
  f(x6) = x6*sqrt(x2)-0.002597*sqrt(x2*x4*xs) #
  f(x7) = x7*sqrt(x4)-0.003448*sqrt(x1*x4*xs) #
  f(x8) = x8*x4-1.799e-5*x2*xs #
  f(x9) = x9*x4-0.0002155*x1*sqrt(x3*xs) #
  f(x10) = x10*x4^2-3.846e-5*x4^2*xs #
  R = 40 #
  xs = x1+x2+x3+x4+x5+x6+x7+x8+x9+x10 #
  x1(0)=2
  x2(0)=5
  x3(0)=80
  x4(0)=1
  x5(0)=0
  x6(0)=0
  x7(0)=0
  x8(0)=0
  x9(0)=20
  x10(0)=5
       
Variable/function values Variable Value f(x)
  x1 2 0
  x2 5 0
  x3 80 2
  x4 1 0
  x5 0 -0.965
  x6 0 -0.062
  x7 0 -0.052
  x8 0 -0.010
  x9 20 19.959
  x10 5 4.996
  R 40  
  xs 113  
       
Solution Variable Value f(x)
  x1 2.99763549788728 -4.441E-16
  x2 3.96642685827836 -1.421E-14
  x3 79.9996980829447 -8.882E-16
  x4 0.00236450211272 0
  x5 0.00060383411050 -2.168E-19
  x6 0.00136594705508 -2.168E-18
  x7 0.06457266816721 0
  x8 3.53081557628766 -6.939E-18
  x9 26.43154979533460 -3.469E-17
  x10 0.00449980202242 -1.323E-23
  R 40  
  xs 116.9995325642010  
       
Additional information Only constrained algorithm that keeps the values of x1,x2,x3 and x4
  positive throughout the iterations converges from initial guesses 2 and 3.