Seveneq3b

Name: Seveneq3b - Flow Distribution in a Pipeline Network - Calculated Friction Factor
Source: Cutlip, M. B. and Shacham, M, Problem Solving in Chemical
  Engineering with Numerical Methods, Prentice Hall Inc., 1999
Reference/s

 

       
Model: 7 implicit equations, indep. variables q01, q12, q13, q24, q23, q34, q45
  Lower difficulty level
  Constraints:none
  Discontinuities: Undefined for qij<=0
       
 

Initial estimates: 1.(0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1)

2.(-0.1, -0.1, -0.1, -0.1,-0.1, -0.1, -0.1);

  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. Flow Distribution in a Pipeline Network - Calculated Friction Factor |POLVER05_3

EXCEL FILE 

f(q01)=q01-q12-q13 #

TEXT FILE 

f(q12)=q12-q24-q23 #

POLYMATH FILE 

f(q13)=q23+q13-q34 #
  f(q24)=q24+q34-q45 #
  f(q23)=k01*q01^2+k12*q12^2+k24*q24^2+k45*q45^2+deltaPUMP #
  f(q34)=k13*q13^2-k23*q23^2-k12*q12^2 #
  f(q45)=k23*q23^2+k34*q34^2-k24*q24^2 #
  rho=997.08 #
  D=0.154 #
  pi=3.1416 #
  mu=8.937e-4 #
  deltaPUMP=-15.e5 #
  ed=4.6e-5/D #
 

fF01=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q01*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q01*mu))))^2) #

 

fF12=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q12*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q12*rho))))^2) #

 

fF24=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q24*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q24*rho))))^2) #

 

fF45=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q45*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q45*rho))))^2) #

 

fF13=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q13*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q13*rho))))^2) #

 

fF23=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q23*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q23*rho))))^2) #

 

fF34=1/(16*(log(ed/3.7-5.02*pi*D*mu/(4*q34*rho)*log(ed/3.7

+14.5*pi*D*mu/(4*q34*rho))))^2) #

  k01=32*fF01*rho*100/(pi^2*D^5) #
  k12=32*fF12*rho*300/(pi^2*D^5) #
  k24=32*fF24*rho*1200/(pi^2*D^5) #
  k45=32*fF45*rho*300/(pi^2*D^5) #
  k13=32*fF13*rho*1200/(pi^2*D^5) #
  k23=32*fF23*rho*300/(pi^2*D^5) #
  k34=32*fF34*rho*1200/(pi^2*D^5) #
  q01(0)=0.1
  q12(0)=0.1
  q13(0)=0.1
  q24(0)=0.1
  q23(0)=0.1
  q34(0)=0.1
  q45(0)=0.1
       
Variable/function values Variable Value f(x)
  q01 0.1 -0.1
  q12 0.1 -0.1
  q13 0.1 0.1
  q24 0.1 0.1
  q23 0.1 1.2756E+06
  q34 0.1 8.7962E+05
  q45 0.100 4.3981E+05
  rho 997.080  
  D 0.154  
  pi 3.142  
  mu 0.001  
  deltaPUMP -1500000  
  ed 2.9870E-04  
  fF01 3.6624E-03  
  fF12 3.9280E-03  
  fF24 3.9280E-03  
  fF45 3.9280E-03  
  fF13 3.9280E-03  
  fF23 3.9280E-03  
  fF34 3.9280E-03  
  k01 1.3669E+07  
  k12 4.3981E+07  
  k24 1.7592E+08  
  k45 4.3981E+07  
  k13 1.7592E+08  
  k23 4.3981E+07  
  k34 1.7592E+08  
       
Solution Variable Value f(x)
  q01 0.110237410418775 -6.9389E-18
  q12 0.073312448014583 3.4694E-18
  q13 0.036924962404192 0
  q24 0.055534266884471 4.16E-17
  q23 0.017778181130112 0
  q34 0.054703143534304 1.1350E-09
  q45 0.110237410418774 8.15E-10
  rho 997.08  
  D 0.154  
  pi 3.1416  
  mu 0.0008937  
  deltaPUMP -1500000  
  ed 0.000298701298701  
  fF01 0.003671115732774  
  fF12 0.003991182117464  
  fF24 0.004062318148155  
  fF45 0.003911224372972  
  fF13 0.004196830275841  
  fF23 0.004547355921332  
  fF34 0.004066622211574  
  k01 13701643.97525590  
  k12 44688667.20193340  
  k24 181940666.64801900  
  k45 43793392.33632400  
  k13 187965115.07645600  
  k23 50916061.81735610  
  k34 182133434.45672300  
       
Additional information Initial guesses 2 and 3 do not satisfy the constraints