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I have two coupled equations, one of which is continuity. Basically, my problem comes down to the following system:

(1) [itex]u=f(v)[/itex] (similarly, [itex]v=g(u)[/itex]. Here, u and v are the components of a vector field, ie u=u(x,y) and v=v(x,y).

(2) Continuity: [itex]\nabla \cdot \textbf{u} = 0[/itex] or [itex]u_{x}+v_{y}=0[/itex]

From here, I can find the following expressions

[itex]u_{x} = -g_{y} \left( u \right)[/itex]

[itex]v_{y} = -f_{x} \left( v \right)[/itex]

Which I think leaves an equation of the form [itex]G \left( u,u_{x},u_{y} \right)=0[/itex] and [itex]F \left( v,v_{x},v_{y} \right)=0[/itex]

It seems to me my original problem has two variables and I have two equations. I think this should be solvable, but I don't know how. Any help please? Thanks in advance!

--edit-- p.s. I'm looking for a numerical (discrete) solution.

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# How to solve two coupled pde's

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