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Hi~ I have a question about "Linearization point" in Acoustics module

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Two Questions:
1. I don't know the meaning of "Values of Linearization point" and "Value of eigenvalue linearization point"

2. How to solve the "nonlinear eigenvalue problem?"



I am studying the "Combustion Instability" using COMSOL.

I am using "Pressure Acoustic in frequency domain"

In my case, a pressure gradient is in a monopole sourceterm.

Therefore, the governing equation turns into the below form.

------> (A + wB + w^2)p = Cp
*A,B,C: Constant, w: angular frequency, p: pressure

It is a nonlinear eigenvalue problem, so to solve this equation, there are well-known algorithms. (Arnoldi method, Krylov-Schur method)

In order to solve the above equation, how to handle the options in COMSOL?

In the present, I select the "Initial expression" and "Zero" in "Values of linearization" menu.
And, I enable the "Transform point" option and write the value which came from the calculation.

I repeat again and again until the "value of tramsform point" is same with the "value of solution from COMSOL calculation" (Converging process)

Am I RIGHT doing like this? -------------Question2

Also, could anyone let me know the meaning of "Values of Linearization point" and "Value of eigenvalue linearization point"? -------------Question1


0 Replies Last Post 20 gen 2016, 21:10 GMT-5
COMSOL Moderator

Hello Seungtaek Oh

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