Seveneq4

Name: Seveneq4 - Water Distribution Network
Source: Ingels, D. M. and Powers, J. E., Chem. Eng. Progress. 60(2), 65(1964)
Reference/s Cutlip, M. B. and Shacham, M, Problem Solving in Chemical
  Engineering with Numerical Methods, Prentice Hall Inc., 1999
       
Model: 7 implicit equations, indep. variables q12, q14, q23, q43, q35, q65, q46
  Lower difficulty level
  Constraints:none
  Discontinuities: none
  Initial estimates: 1.(1000, 500, 600, 200, 300, 100, 400), 2.(-1000, -500, -600, -200, -300, -100,- 400);
  3.(0, 0, 0, 0, 0, 0, 0, 0, 0) 4.(10, 10, 10, 10, 10, 10, 10, 10, 10);
       
Solved by Shacham, M., POLYMATH 5.1, build 19, April 22, 2001
       
Model Eqs. Water Distribution Network |POLVER05_3

EXCEL FILE 

f(q12)=1400-q12-q14 #

TEXT FILE 

f(q14)=dp12+dp23-dp43-fc*q14^2*1000/(8^5) #

POLYMATH FILE 

f(q23)=q12-420-q23 #
  f(q43)=q43+q23-420-q35 #
  f(q35)=q35+q65-420 #
  f(q65)=q46-140-q65 #
  f(q46)=dp43+dp35-fc*0.2572*q65^2-fc*0.1286*q46^2 #
  fc=8.7*10^(-4) #
  dp12=fc*2000*q12*q12/(12^5) #
  dp23=fc*1000*q23*q23/(8^5) #
  dp43=fc*2000*q43^2/(8^5) #
  dp35=fc*1000*q35^2/(6^5) #
  q12(0)=1000
  q14(0)=500
  q23(0)=600
  q43(0)=200
  q35(0)=300
  q65(0)=100
  q46(0)=400
       
Variable/function values Variable Value f(x)
  q12 1000 -100
  q14 500 7.7892
  q23 600 -20
  q43 200 80
  q35 300 -20
  q65 100 160
  q46 400.000 -7.9453
  fc 0.001  
  dp12 6.993  
  dp23 9.558  
  dp43 2.124  
  dp35 10.0694  
       
Solution Variable Value f(x)
  q12 872.751598594702 0
  q14 527.248401405298 -4.4409E-15
  q23 452.751598594702 0
  q43 252.590830181724 -5.6843E-14
  q35 285.342428776427 5.6843E-14
  q65 134.657571223573 0
  q46 274.657571223573 0
  fc 0.00087  
  dp12 5.32628405493795  
  dp23 5.44238552020724  
  dp43 3.38793035387858  
  dp35 9.10952449128423