Solving PDE w/ complex Neumann boundary condition
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Hi,
I am working on combustion instabilities and therefore looking into eigenmodes. To solve for the pressure distribution u, I have to define my boundary conditions. As I understood from the Mathworks website, the Neumann BC is written in a general form as grad(u) + q * u = g. I am able to solve for real values of q (and I'm setting g=0), this being one of my BC:
neumann = [1 0 6 6 '0.1000' '0.0000']';
Can anybody tell me if there is a possibility to extent q values to imaginary values and thus q = q_r + iq_i?
Regards,
Simon R2011a
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Accepted Answer
Bill Greene
on 17 Aug 2013
Hi,
The expression within the single quotes has to be a valid MATLAB arithmetic expression. To define a complex number in MATLAB do either:
a + i*b
or
a + sqrt(-1)*b
The second form can be useful when the variable i has been redefined for some other purpose such as a loop index. So, in some ways, it is safer.
Bill
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More Answers (3)
Bill Greene
on 16 Aug 2013
Hi,
Yes, PDE Toolbox allows the BC (or PDE) coefficients to be imaginary. Are you running into a particular problem?
Bill
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