Seveneq2b

Name: Seveneq2b - Esterification Reaction in Two Consecutive CSTRs - Revised Form.
Source: Seadet, J. D. et al., Computers chem. Engng.,14 71(1990).
       
Reference/s Gupta, Y.P. (1995). Ind. Eng. Chem. Res. 34, 536-544
       
Model: 7 implicit equations, indep. variables A, B, C, D, E, F and G
  Higher difficulty level
  Constraints: All the variables must be >=0
  Discontinuities: none
  Initial estimates: 1. (80, 7, 60, 7, 0.5, 4, 0.05 ); 2. (100, 10, 50, 10, 0.5, 4, 0.05);
  3.(50, 5, 25, 5, 0.5, 4, 0.05);
 

 

 

 

Solved by Shacham, M., POLYMATH 5.1, build 19, April 15, 2001
       
Model Eqs. Esterification Reaction in Two Consecutive CSTRs - Revised Form |POLVER05_3

EXCEL FILE 

f(A) = 5.5*(D-B)*(B+C)-B*(A-B-C) #

TEXT FILE 

f(B) = 3.5*(0.888*A-C-D)*(B+C)-C*(A-B-C) #

POLYMATH FILE 

f(C) = 5.5*(0.0986*A-0.01*(1.098*A-B-9*D-E-F+G)

-(B+E))*(E+F)-E*(1.098*A-B-9*D-E-F+G) #

 

f(D) = 3.5*(0.986*A-9*D-F-0.0986*A+0.01*(1.098*A-B-9*D-E-F+G))*(E+F)

-F*(1.098*A-B-9*D-E-F+G) #

  f(E) = 2056.4*(0.0986*A-D)^2-D*(A-B-C)^2 #
  f(F) = 0.61177-(A*0.0986-D)+0.01*(1.098*A-B-9*D-E-F+G) #
 

f(G) = 0.04*(74.12*(0.986*A-10*D)+222.24*(0.0986*A-D)+18*(D-B)+278.84*D

+98.09*0.0136*A)/98.01-0.0136*A-G#

  A(0)=80
  B(0)=7
  C(0)=60
  D(0)=7
  E(0)=.5
  F(0)=4
  G(0)=0.06
       
Variable/function values Variable Value f(x)
  A 80 -9.1000E+01
  B 7 1.6738E+02
  C 60 -4.1350E-01
  D 7 1.1384E+01
  E 0.5 4.3856E+02
  F 4 -1.4223E-01
  G 0.06 4.1322E-02
       
Solution Variable Value f(x)
  A 80.5396204210231 1.2790E-13
  B 6.9730107905982 1.9327E-12
  C 61.1233326471120 2.6645E-15
  D 7.2046801639777 -5.6843E-14
  E 0.5477285762994 -6.8212E-13
  F 3.6537136469003 6.5226E-16
  G 0.0597122208353 -7.5634E-16
       
False solution Variable Value f(x)
  A 23.0651984622826 -5.6268E-14
  B 6.22288010558E-15 5.6252E-13
  C 3.53662923782E-15 -1.5987E-13
  D 1.6257068608802 -3.3218E-12
  E 2.0467274231075 -9.5611E-11
  F 5.1231474057701 6.4115E-15
  G 0.1508194152979 3.9357E-14
       
       
Additional information Converge to a false solution from initial guesses 2 and 3.
  The last solution is a false one because the original equations
  1 and 2 (see Seveneq2a) are not satisfied at that point
  There are several inconsistencies between the two formulations
  of the model equations appearing in the original source. We
  attempted to correct the equations to obtain solution close
  to the one shown in the original source.