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Stream + source/sink pair: Rankine closed bodies


\begin{figure}
\centering\epsfig{file=lfig1018.eps,height=2.5in,clip=}\end{figure}

To have a closed body, a necessary condition is to have $\sum {m_{\mbox{in body}} } = 0$

2D Rankine ovoid:


\begin{displaymath}\phi = Ux + \frac{m}{2\pi }\left( {\ell n\sqrt {\left( {x + a...
... y^2} - \ell n\sqrt {\left( {x - a} \right)^2 + y^2} }
\right)
\end{displaymath}

Stagnation Points for 2D Rankine ovoid

3D Rankine ovoid:


\begin{displaymath}\phi = Ux - \frac{m}{4\pi }\left[ {\frac{1}{\sqrt {\left( {x ...
...rac{1}{\sqrt {\left( {x - a} \right)^2 + y^2 + z^2} }}
\right]
\end{displaymath}

1.
Question: Find the stagnation points for the 3D Rankine ovoid.

(a)
Hint: derive the velocity vector $\vec{v} = 0$.
(b)
Hint: solve $\vec{v} = 0$ for $(x,y,z)$.

2.
Question: Find the radius $R_{0}$ of the body.

(a)
Hint: mass flux at the half body equals $m$.

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