How to solve nonlinear coupled ode by Shooting method .
17 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Chandan Kumawat
am 13 Okt. 2019
Kommentiert: darova
am 2 Nov. 2019
Respected sir ,
I am getting problem to solve non linear coupled BVP by shooting method . Can you help me to solve that problem?
My problem is
F'''=(1/(1+epsilon1*(1-G)))*(A*F'+.5*t*A*F''+(F')^2-F*F''+epsilon1*G'*F''-lambda*G-delta*H+M*F'-(-1+epsilon1*G-epsilon1)*bita*F');
G''=(1/(1+epsilon2*G+Nr))*(Pr*(2*A*G+.5*A*t*G'+F'*G-F*G'-M*Ec*(F')^2-Ec*(1-epsilon1*G'+epsilon1)*(F'')^2)-epsilon2*(G')^2);
H''= Sc*(2*A*H+.5*A*t*H'+F'*H-F*H'+Rex*Zai*H);
where A=0 ; epsilon1= 0 ; epsilon2=1; lambda= 1; delta=1; bita=0; Nr=.1; Pr=5; M=.5;
Ec=.1 ; Sc=1; Rex= .3 ; Zai= .1 ;
and F(0)=0 , F'(0)=1 F'(infity)=0 G(0)=1 G(infity)=0 H(0)= 1 H(infity)=0
and F''(0) , G'(0) & H'(0) we have to guess
so tell me how to solve by shooting method with using rk -4 method .
2 Kommentare
darova
am 13 Okt. 2019
What have you tried? What ideas do you have? Did you see examples in MATLAB help?
Akzeptierte Antwort
Weitere Antworten (1)
darova
am 14 Okt. 2019
Try bvp4c
Suggestion:
F0 = y(1);
%% ...
H1 = y(7);
% and use these variables to make your code more redable
dy(1) = F1;
%% ..
You can also use temporary variables to make your code simpler
dy(3) = 1/(1+e1*(1-G0))* ...
(A*F1 + 0.5*t*A*F2 + F1^2 - F0*F2 + e1*G1*F2 - lambda*G0 - delta*H0 + M*F1 - (-1+e1*G0-e1)*bita*F1);
%%
TEMP0 = 1/(1+e1*(1-G0));
TEMP1 = 0.5*t*A*F2;
TEMP2 = e1*G1*F2;
TEMP3 = (-1+e1*G0-e1)*bita*F1;
dy(3) = TEMP0 * (A*F1 + TEMP1 + F1^2 - F0*F2 + TEMP2 - lambda*G0 - delta*H0 + M*F1 - TEMP3);
See attached scripts
10 Kommentare
darova
am 17 Okt. 2019
I just changed main code
init = [0 1 -0.58 1 -1.52 1 -1.12];
% solinit = bvpinit([0 2],zeros(1,7));
% sol = bvp4c(@new,@bvpf,solinit);
[t,y] = ode45(@new,[0 2], init);
% plot(sol.x,sol.y)
plot(t,y)
legend('F','dF','d2F','G','dG','H','dH')
I took initial conditions from last calc. There is no rule for F2(0) G1(0) & H1(0) values, only guessing or something like bvp4c
Siehe auch
Kategorien
Mehr zu Boundary Value Problems finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!