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mike79
Jun23-08, 09:11 AM
Hi everybody,
could anyone help me in the linearization of the following non linear non-homogeneous ODE?

A*dy/dt+B*y^(4)=C

where A, B and C are constants. y is a function of t. is it possible to reduce this equation to a Riccati equation? do you know any analytical, approximate or not, methods to solve the equation?

thanks in advance

Defennder
Jun23-08, 09:55 AM
Just to be clear, is this the DE:

A \frac{dy}{dt} + By^4 = C

If so, then note that you can easily express it as a Bernoulli differential equation (http://en.wikipedia.org/wiki/Bernoulli_differential_equation)and solve it directly without having to approximate it.

mike79
Jun27-08, 10:06 AM
the DE is right...the BERNOULLI equation is homogeneous and I actually can't tarnsform my equation in a Bernoulli one. can you suggest me how to transform it?

Defennder
Jun27-08, 10:58 PM
I just had a second look at the DE and realised that there is no need to solve it as a Bernoulli DE. The original DE is separable, though the resulting integral is a little tough to integrate, but certainly doable.

mike79
Jul2-08, 08:12 AM
i have found in literature the Chini equation, which is similar to the equation I'm trying to solve. unfortunately i can't found the solution. can everyone help me, please?

HallsofIvy
Jul2-08, 08:17 AM
Defennder has already pointed out that this equation is separable:
/frac{Ady}{C- By^4}= dt
Integrate both sides, using "partial fractions" on the left.