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How to set a boundary condition that is neither Neumann nor dirichlet type?

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Hi folks

I am solving a 2D time-dependent wave equation, and the variable is p.

The boundary condition I want to impose on x=0 is something neither Neumann BC nor Dirichlet BC, and is as follow
(or see attachment )

pxt - ptt + 1/2*pyy = 0

If it was something like this, px - ptt + 1/2*pyy = 0, then I know how to do it: just throw ptt-1/2*pyy to the "g" term in the Neumann BC. But unfortunately, it is not...so I am stuck here.

I appreciate it very much if anyone can throw me some pointers here
Thanks in advance

Yun


1 Reply Last Post 17 août 2010, 05:21 UTC−4

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Posted: 1 decade ago 17 août 2010, 05:21 UTC−4
Hello Yun,
I have a problem similar to yours.
I need to solve a 2D time-dependent system of PDEs, with the variables u and v.
The boundary condition at x=0 also involves the time derive of the variables, and it is as follow
vt*ux+v*uxt-ut*vx-u*vxt=0
If you find the solution to your problem, and you can help to solve mine.
If anyone know how to set the boundary conditions involving time derive of the variables can be of great help.
Thanks in advance
Tianyou
Hello Yun, I have a problem similar to yours. I need to solve a 2D time-dependent system of PDEs, with the variables u and v. The boundary condition at x=0 also involves the time derive of the variables, and it is as follow vt*ux+v*uxt-ut*vx-u*vxt=0 If you find the solution to your problem, and you can help to solve mine. If anyone know how to set the boundary conditions involving time derive of the variables can be of great help. Thanks in advance Tianyou

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