impedance boundary conditions

caltek

Hello All.

In Acoustics, impedance boundary conditions are defined as Robin conditions (sum of normal derivative of the complex acoustic pressure plus the pressure itself); the right-hand side is a function g defined on the boundary. Am I correct to say that the function g describes possible sources of acoustic radiation, hence it is 0 for scattering problems and nonzero for radiation problems ?

Thank you for your help to understand!
David.