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Up: Free-surface waves: linear superposition, Previous: Conservation of energy equation

Steady ship waves, wave resistance


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Wave resistance drag on ship $D$.
\begin{align}\mbox{Rate of work done} & = \mbox{rate of energy increase} \notag
...
...{1 \over
4}\rho gA^2}\limits_{\mbox{\tiny {energy / area}}} \notag
\end{align}

Question: Amplitude A = ? (depends on U, geometry)
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Superimpose a bow wave ( $\eta _{b})$ and a stern wave ( $\eta _{s})$:
\begin{align}\eta _b & = a\cos \left( {kx} \right)\mbox{\ and\ }\eta _s = - a\co...
...sin ^2\left( {\textstyle{1 \over 2}\frac{gl}{U^2}} \right)
\notag
\end{align}

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Steady ship waves (deep water)
\begin{align}U = & \mbox{\ ship speed } \notag \\
V_p = & \sqrt {\frac{g}{k}} ...
...t) \cong \rho ga^2\sin ^2\left(
{\frac{1}{2F_L^2 }} \right) \notag
\end{align}

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