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2D corner flow

Potential function:


\begin{displaymath}\phi = r^\alpha \cos (\alpha \theta), \notag
\end{displaymath}

Stream function:


\begin{displaymath}\psi = r^\alpha \sin (\alpha\theta) \notag
\end{displaymath}

Velocity vector components (polar coordinates):


\begin{displaymath}\begin{array}{l}
u_r = \frac{\partial \phi }{\partial r} = \a...
... n\pi , n =
0,\pm 1,\pm 2,\ldots \hspace{1.5in}\\
\end{array}\end{displaymath}

1.
interior corner flow - stagnation point origin: $\alpha > $ 1.

e.g. $\alpha$ = 1, $\theta _0 = 0,\pi ,2\pi,\ \ \ u = 1,\ v = 0$


\begin{figure}
\centering\epsfig{file=lfig1024.eps,height=2in,clip=}\notag
\end{figure}


\begin{figure}
\centering\epsfig{file=lfig1025.eps,height=2in,clip=}\notag
\end{figure}


\begin{figure}
\centering\epsfig{file=lfig1026.eps,height=2in,clip=}\notag
\end{figure}


\begin{figure}
\centering\epsfig{file=lfig1027.eps,height=3in,clip=}\notag
\end{figure}

2.
Exterior corner flow, $\vert v \vert \to
\infty $ at origin: $\alpha < 1 (\raise.5ex\hbox{$\scriptstyle
1$ }\kern-.1em/ \kern-.15em\lower.25ex\hbox{$\scriptstyle 2$ } \le
\alpha < 1$). $\theta _0 = 0,\frac{\pi }{\alpha }$ only. Since we need $\theta _0 \le 2\pi $, we therefore require $\frac{\pi
}{\alpha } \le 2\pi ,$ i.e. $\alpha \ge 1 \mathord{\left/
{\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2$ only.
e.g. $\alpha = 1 \mathord{\left/ {\vphantom {1 2}}
\right. \kern-\nulldelimiterspace} 2, \theta _0 = 0, 2\pi $ ( $\raise.5ex\hbox{$\scriptstyle 1$ }\kern-.1em/
\kern-.15em\lower.25ex\hbox{$\scriptstyle 2$ } $ infinite plate, flow around a tip)


\begin{figure}
\centering\epsfig{file=lfig1028.eps,height=1in,clip=}\notag
\end{figure}

$ \alpha = 2 \mathord{\left/ {\vphantom {2 3}} \right.
\kern-\nulldelimiterspace} 3, \theta _0 = 0,\frac{3\pi }{2}$ ($90^{o}$ exterior corner)


\begin{figure}
\centering\epsfig{file=lfig1029.eps,height=2in,clip=}\notag
\end{figure}



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