Dear all,
I wanted to solve this two set of non-linear ODE using matlab :
are constant
The boundary conditions are the following :
and at
and at ( ν is an arbitrary constant < 1)
this the code that I constracted so far
function bvp4c_mathworksrspan = [0.01 1];init = zeros(1,4);solinit = bvpinit(rspan,init);sol = bvp4c(@ode4,@bc4,solinit);eta = sol.x;theta = sol.y(1,:);Sr = sol.y(2,:);plot(eta,theta)hold onplot(eta,Sr,'r')hold offlegend('Nr(r)','\beta(r)')endfunction du = ode4(eta,u)theta = u(1);Sr = u(2); % beta
dtheta = u(3); % d(theta)/dr
dSr = u(4); % d(Sr)/dr
lambda =15.94;P=12; %P=F*a/D; F is the applied force ; a radius of the membrane ; D = E*h^3/12(1-nu^2)
alpha = 3; %alpha =C*a^2/D ; C in-plane stifnnes
du(1) = dtheta;du(2) = dSr;du(3) = (P/(2*pi*eta)-(1/eta)*dtheta+(1/eta^2+lambda^2+Sr));du(4) = (alpha*theta^2/(2*eta^2)+3/eta*dSr);du(4) = du(4)/eta;endfunction res = bc4(u0, ur)res = [ur(1)-0 ur(2)-0 ur(3)-0 u0(2)-0];end
Best Answer