Difference between revisions of "Laplace's Equation"

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The velocity potential satisfies the Laplace equation because of the assumptions that the fluid is inviscid, incompressible, and irrotational.
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The velocity potential <math>\Phi</math> satisfies Laplace's equation if we can assume that the fluid is inviscid, incompressible, and irrotational.
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Laplace's equation is the following in two dimensions
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<math>\nabla^2\phi = \frac{\partial^2 \phi}{\partial x^2}
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+ \frac{\partial^2 \phi}{\partial z^2} = 0</math>
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and in three dimensions
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<math>\nabla^2\phi = \frac{\partial^2 \phi}{\partial x^2}
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+ \frac{\partial^2 \phi}{\partial y^2}+ \frac{\partial^2 \phi}{\partial z^2} = 0</math>
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The typical solution to Laplace's equation oscillates in one direction and
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decays in another. The linear water wave arises as a boundary wave which
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decays in the vertical direction and has wave properties in the horizontal
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direction.
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==See Also==
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* [http://en.wikipedia.org/wiki/Laplace%27s_equation Laplace's equation]

Latest revision as of 03:19, 23 September 2008

The velocity potential [math]\displaystyle{ \Phi }[/math] satisfies Laplace's equation if we can assume that the fluid is inviscid, incompressible, and irrotational.

Laplace's equation is the following in two dimensions

[math]\displaystyle{ \nabla^2\phi = \frac{\partial^2 \phi}{\partial x^2} + \frac{\partial^2 \phi}{\partial z^2} = 0 }[/math]

and in three dimensions

[math]\displaystyle{ \nabla^2\phi = \frac{\partial^2 \phi}{\partial x^2} + \frac{\partial^2 \phi}{\partial y^2}+ \frac{\partial^2 \phi}{\partial z^2} = 0 }[/math]

The typical solution to Laplace's equation oscillates in one direction and decays in another. The linear water wave arises as a boundary wave which decays in the vertical direction and has wave properties in the horizontal direction.

See Also