Solving Coupled PDEs Numerically with Unknown Functions u(x,y) and v(x,y)

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Two coupled partial differential equations involving unknown functions u(x,y) and v(x,y) are being discussed, with the challenge of solving them numerically due to the non-linearity of one equation. A finite-timestep approach is recommended, emphasizing the importance of a small timestep Δx relative to expected solution fluctuations. The iterative form of the equations can be established, allowing for solutions to be generated from initial boundary values using computational methods. The problem may relate to complex analysis, suggesting that one equation could be reformulated in terms of a complex variable. Overall, the discussion focuses on numerical methods and potential analytical insights for solving the coupled PDEs.
MathNerd
I have two unknown function namely u(x,y) and v(x,y). These functions are part of two coupled partial differential equations. I realize that it will be almost impossible to get a general solution seeing as one on the PDEs is non-linear. But given a set of boundary conditions I wish to solve for these unknown functions numerically. I don’t quite know how to go about this though, so any help would be appreciated. The equations are attached to this thread
 

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If I wanted to solve this numerically, I'd use a finite-timestep approach.

Remember:

\frac{\partial f(x)}{\partial x} \equiv \lim_{\Delta x \rightarrow 0}\frac{f(x+\Delta x)-f(x)}{\Delta x}

So: just make sure that your timestep \Delta x is small compared to the (expected) fluctuations in your solutions. In that case, you can re-write your equations in an iterative form (note that I used \Delta x=1):

f(n+1) = {\rm some\; function\; of}\; f(n)

which you can do for both of your functions. Now, you can start with your boundry values (for time n=0) and generate the solutions for n>0 with a computer. Computationally intensive, but that should be no problem for your equations...

Succes!
 
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It looks to me as though this is a problem from complex analysis. Your second equation is the analyticity condition for a function of a complex variable. Perhaps the first equation is simply expressed in terms of that function.

dhris
 

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