Difference between revisions of "Removing the Depth Dependence"

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If we have a problem in which the water depth is of constant depth <math>z=-d/math> (we are assuming
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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
 
are also constant with respect to the depth then we can remove the depth dependence by assuming
 
are also constant with respect to the depth then we can remove the depth dependence by assuming

Revision as of 11:09, 22 April 2006

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.