Template:Standard linear wave scattering equations without body condition

[math]\displaystyle{ \Delta\phi=0, \, -h\lt z\lt 0,\,\,\,\mathbf{x} \in \Omega }[/math] [math]\displaystyle{ \partial_n\phi = 0, \, z=-h, }[/math] [math]\displaystyle{ \partial_n \phi =\mathrm{i} \omega \zeta\,z=0,\,\,\mathbf{x} \in F, }[/math] [math]\displaystyle{ \mathrm{i} \omega \phi = -\zeta,\,z=0,\,\,\mathbf{x} \in F, }[/math]

The latter two can be combined as

[math]\displaystyle{ \partial_n \phi = \omega^2 \phi,\,z=0,\,\,\mathbf{x} \in F, }[/math]

where [math]\displaystyle{ \alpha = \omega^2 }[/math]