MATLAB: Non Linear DE solving using ODE45

nonlinearode45

I am trying to solve a non linear differential equation which is df/dt=-.3223+(1/9)*(175.9384/f) through using this command :

dfdt=@(t,f) -.3223+(1/9)*(175.9384/f);

[tv,fv]=ode45(dfdt,[0 5],59.9581);

plot(tv,fv)

Why i am getting linear plot here?

Best Answer

Hi Muhammad,

with that set of constants, the time has not been run out far enough to see the final result. Try changing the time limits to, say, [0 2000]. Then you can see f approach its asymptotic value (df/dt = 0) of

175.9384/(9*.3223)
ans = 60.6538

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Best wishes

Torsten.

Best Answer

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