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In this section we will first plot the variation of the x component of the velocity along the outlet. Then we will plot the Blasius solution and to see how the numerical solution compares. In order to start the process (Click) Results > Plots > XY Plot... > Set Up.. as shown below.

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https://confluence.cornell.edu/download/attachments/118771111/xyplotsetup_Full.png

In the Solution XY Plot menu make sure that Position on Y Axis is selected , and X is set to 0 and Y is set to 1. This tells FLUENT to plot the y-coordinate value on the ordinate of the graph. Next, select Velocity... for the first box underneath X Axis Function and select X Velocity for the second box. Please note that X Axis Function and Y Axis Function describe the x and y axes of the graph, which should not be confused with the x and y directions of the geometry. Finally, select outlet under Surfaces since we are plotting the x component of the velocity along the outlet. This finishes setting up the plotting parameters. Your Solution XY Plot menu should look exactly the same as the following image.

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https://confluence.cornell.edu/download/attachments/118771111/SolXY1_Full.png

Now, click Plot. The plot of the x component of the velocity as a function of distance along the outlet now appears.

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https://confluence.cornell.edu/download/attachments/118771111/XVelPlot1_Full.png

In order to increase the legibility of the graph, we will plot the data as a line rather than points. To turn on the line feature, click on Curves... in the Solution XY Plot menu. Then, set Pattern to Center, set the Weight to 2 and select nothing for Symbol, as shown below.

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https://confluence.cornell.edu/download/attachments/118771111/CurveMen_Full.png

Next, click
Apply in the Curves - Solution XY Plot menu. Next, close the Curves - Solution XY Plot menu.

Now, the range of the y axis will be truncated, as we are not interested in far field velocity. Furthermore, the grid lines will be turned on. In order to implement these two changes. First click Axes in the Solution XY Plot menu. Next, select Y for Axis, deselect Auto Range, select Major Rules, select Minor Rules. Then, set Minimum to 0 and set Maximum to 1.2. Your Axes - Solution XY Plot menu, should look exactly like the image below.

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https://confluence.cornell.edu/download/attachments/118771111/AxesMen1_Full.png

Then, click Apply in the Axes - Solution XY Plot menu. Now, select X for Axis and select Major Rules and Minor Rules, as shown below.

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https://confluence.cornell.edu/download/attachments/118771111/Axes2_Full.png

Next, click Apply in the Axes - Solution XY Plot menu. Close the Axes - Solution XY Plot menu. Now, click Plot menu in the Solution XY Plot menu. You should obtain the following output.

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https://confluence.cornell.edu/download/attachments/118771111/Plot3_Full.png

It is of interest to compare the numerical velocity profile to the velocity profile obtained from the Blasius solution. In order to plot the theoretical results, first click here to download the necessary file. Save the file to your working directory. Next, go to the Solution XY Plot menu and click Load File... and select the file that you just downloaded, BlasiusU.xy. Lastly, click Plot in the Solution XY Plot menu. You should then obtain the following figure.

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https://confluence.cornell.edu/download/attachments/118771111/Plot4_Full.png

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