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gg0520

铜虫 (初入文坛)

应助: 0 (幼儿园)
金币: 103
帖子: 26
在线: 1.4小时
虫号: 730082
注册: 2009-03-24
性别: GG
专业: 化学工程

[交流] 【求助】fsolve求解问题

function xFsovle5  % Pn+M--->Dn+P1
clear all;
clc;
format short g;
global Ka Ki Kp Ktm Ktal Kth Kd Qti0 Qt0 Qp0 QH0 Mti Mt Mp MH T V Qv Qs
Ka=0.0013;Ki=108.85;Kp=108.85;Ktm=0.012;Ktal=0.12;Kth=4.8;Kd=0.001;  %速率常数
Qti0=3000;Qt0=10000;Qp0=817500000;QH0=4000000;                   Mti=193.9;                                                          Mt=114;                                                          Mp=42;                                                             MH=2;                                                             T=3600;
V=90;
Qv=4.608206;
Qs=0.00855230;
x0=[6.05e-006  1.1413e+003 120.5079 2.8374 0.0049237 3.6821 5.5035e+003 18.1943 1.3606e+004 2.0337e+007 0.0043327]'; [x,FVAL,EXITFLAG,output]=fsolve(@NonlinEqs,x0)
Mn=42*(x(6)+x(9))/(x(5)+x(8))
Mw=42*(x(7)+x(10))/(x(6)+x(9))
PDI=Mw/Mn
%-------------------------------------
function f =NonlinEqs(x)
global Ka Ki Kp Ktm Ktal Kth Kd Qti0 Qt0 Qp0 QH0 Mti Mt Mp MH T V Qv Qs
f(1)=Ka*x(11)+(Kth*x(3)^0.5+Ktal*x(4))*x(5)-Ki*x(1)*x(2)-Kd*x(1)+(0-x(1)*Qs)/V; %
f(2)=-Ki*x(1)*x(2)-(Kp*x(2)+Ktm*x(2))*x(5)+(Qp0/(Mp*T)-x(2)*Qv)/V;
f(3)=-Kth*x(5)*x(3)^0.5+(QH0/(MH*T)-x(3)*Qv)/V;
f(4)=-Ktal*x(4)*x(5)+(Qt0/(Mt*T)-x(4)*Qs)/V;
f(5)=Ki*x(1)*x(2)-(Kth*x(3)^0.5+Ktal*x(4)+Kd)*x(5)+(0-x(5)*Qs)/V;
f(6)=Ki*x(1)*x(2)+Kp*x(2)*x(5)-(Kth*x(3)^0.5+Ktm*x(2)+Ktal*x(4)+Kd)*x(6)+Ktm*x(2)*x(5)+(0-x(6)*Qs)/V;
f(7)=Ki*x(1)*x(2)+2*Kp*x(2)*x(6)+Kp*x(2)*x(5)-(Kth*x(3)^0.5+Ktm*x(2)+Ktal*x(4)+Kd)*x(7)+Ktm*x(2)*x(5)+(0-x(7)*Qs)/V;
f(8)=(Kth*x(3)^0.5+Ktm*x(2)+Ktal*x(4)+Kd)*x(5)+(0-x(8)*Qs)/V;
f(9)=(Kth*x(3)^0.5+Ktm*x(2)+Ktal*x(4)+Kd)*x(6)+(0-x(9)*Qs)/V;
f(10)=(Kth*x(3)^0.5+Ktm*x(2)+Ktal*x(4)+Kd)*x(7)+(0-x(10)*Qs)/V;
f(11)=-Ka*x(11)+(1.35/T-x(11)*Qs)/V;
-------------------------------------------------------------------------------
结果为：
Maximum number of function evaluations reached:
increase options.MaxFunEvals.

x =

0.0033832
   1141.3
   11.212
   2.7032
   0.002532
   0.66931
   5503.5
   18.194
      13606
  2.0337e+007
0.0043327

FVAL =

  Columns 1 through 7

   -420.24    -733.23       5.558  -0.00080748    420.24    714.72    1409.1

  Columns 8 through 11

   0.074467    18.849  1.6369e+005 -1.8776e-006

EXITFLAG =

   0

output =

   iterations: 91
      funcCount: 1104
      algorithm: 'trust-region dogleg'
firstorderopt: 6.4012e+008
      message: [1x78 char]

Mn =

      31405

Mw =

      62792

PDI =

   1.9994
感觉程序就根本没有运行一样，初值基本不变，特别是最后几个，无论你怎么改变他们的值，都不会变，而是相应的改变前面的值，请问这是为什么~谢谢~

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