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gibson:teaching:spring-2016:math445:lab9

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gibson:teaching:spring-2016:math445:lab9 [2016/03/29 06:22]
gibson [Math 445 lab 9: 3d graphics]
gibson:teaching:spring-2016:math445:lab9 [2016/03/31 09:39] (current)
vining
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 </​code>​ </​code>​
  
-===== Problem ​5: quiver plot =====+===== Problem ​6: quiver plot =====
  
 The function The function
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 **(b)** In a gentle rainstorm, water will flow down the mountains in the direction of steepest descent, i.e. along the negative of the gradient of $f$. Find the gradient of $f$ using elementary calculus, then make an $x,y$ plot with both contours of the mountain height $f$ and a quiver plot showing the direction of flow of rainwater. ​ **(b)** In a gentle rainstorm, water will flow down the mountains in the direction of steepest descent, i.e. along the negative of the gradient of $f$. Find the gradient of $f$ using elementary calculus, then make an $x,y$ plot with both contours of the mountain height $f$ and a quiver plot showing the direction of flow of rainwater. ​
 +
 +===== Problem 7: inviscid fluid flow within a square corner =====
 +
 +The inviscid 2d fluid flow within a square corner with solid walls at $x=0$ and $y=0$ and the domain $x \geq 0$ and $y \geq 0$ has velocity components
 +
 +\begin{eqnarray*}
 +v_x &= v_0 \, x \\
 +v_y &= -v_0 \, y
 +\end{eqnarray*} ​
 +
 +Make a quiver plot of this flow for $0 \leq x \leq 1$ and $0 \leq y \leq 1$, and with $v_0 = 1$. Label the axes and title the plot.
 +
 +===== Problem 8: inviscid fluid flow past a semicircular bump =====
 +
 +The inviscid 2d fluid flow past a semicircular bump of radius $a$ centered at the origin on a flat wall at $y=0$ has velocity components
 +
 +\begin{eqnarray*}
 +v_x &= v_0 \left(1 - a^2 \frac{x^2 - y^2}{(x^2+y^2)^2}\right) \\
 +v_y &= -2 a v_0 \frac{xy}{(x^2+y^2)^2}
 +\end{eqnarray*} ​
 +
 +Make a quiver plot of this flow for $a=1$, $v_0=1$, $-3 \leq x \leq 3$ and $0 \leq y \leq 3$, excluding the interior of the bump, where $x^2 + y^2 < a^2$. Draw a blue curve that shows the surface of the semicircular bump. Make the $x$ and $y$ axis have the same scale, label the axes, and title the plot. 
  
 ===== Bonus ===== ===== Bonus =====
gibson/teaching/spring-2016/math445/lab9.1459257772.txt.gz · Last modified: 2016/03/29 06:22 by gibson