Difference between revisions of "Removing the Depth Dependence"
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+ | We are considering the [[Frequency Domain Problem]] for linear wave waves. | ||
If we have a problem in which the water depth is of constant depth <math>z=-d </math> (we are assuming | If we have a problem in which the water depth is of constant depth <math>z=-d </math> (we are assuming | ||
the free surface is at <math>z=0</math>) and all the scatters | the free surface is at <math>z=0</math>) and all the scatters |
Revision as of 20:06, 22 April 2006
We are considering the Frequency Domain Problem for linear wave waves. If we have a problem in which the water depth is of constant depth [math]\displaystyle{ z=-d }[/math] (we are assuming the free surface is at [math]\displaystyle{ z=0 }[/math]) and all the scatters are also constant with respect to the depth then we can remove the depth dependence by assuming that the dependence on depth is given by
[math]\displaystyle{ \Phi(x,y,z) = \cosh \big( k (z+d) \big) \phi(x,y) }[/math]
where [math]\displaystyle{ k }[/math] is the positive root of the Dispersion Equation then the problem reduces to Helmholtz's Equation
[math]\displaystyle{ \nabla^2 \phi - k^2 = 0 }[/math]
in the region not occupied by the scatterers.