ut = 3uxx + 2, 0 < x < 4, t > 0,
u(0,t) = 0, u(4,t) = 0, t = 0
u(x,0) = 5sin2πx,0 < x < 4.
(a) Find the steady state solution uE(x)
(b) Find an expression for the solution.
(c) Verify, from the expression of the solution, that limt→∞ u(x, t) = uE (x)
for all x, 0 < x < 4.
The eqaution is:
With boundary condition
And initial conditions
The steady state is, by definition:
The function is now only x-dependent so the partial derivatives become full derivatives and the ordinary differential equation is
And the boundary conditions must still hold:
Integrating (1.5) twice we obtain:
Applying boundary conditions we get the steady state solution.
We would like to turn the system into a homogenous system.
So we write:
When we apply it to the original equation we get:
If we set
the equation becomes homogenous.
For the boundary conditions we ...
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