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https://confluence.cornell.edu/download/attachments/146918520/DirHeatFluxVec_Full.png

Temperature along Y=1m line

Let us extract the temperature values along the horizontal line, y=1m. This is done in two steps:

1. Define a "path" corresponding to y=1m
2. Extract temperature along the path

Define Path

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https://confluence.cornell.edu/download/attachments/146918520/InsConstructGeomFull.PNG

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https://confluence.cornell.edu/download/attachments/146918520/InsertPath_Full.PNG

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Extract temperature along path

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Heat Flux Variation Along Bottom Surface

We'll plot the heat flux crossing the bottom surface as a function of x. The steps involved are:

1. Create a "path" i.e. line corresponding to the bottom surface (boundary). The path will start at (0,0) and end at (1,0).
2. Plot the y-component of the heat flux along this path.
3. Export heat flux values to Excel for further processing
   These steps are demonstrated in the videos below. If the videos don't appear below, try reloading the webpage.

Create Path Corresponding to Bottom Surface

1. Select Model > Construction Geometry > Path.
2. Specify number of samples and end location of path as (1,0). Start location is (0,0) which is the default.
3. Rename path (optional).

 <iframe width="600" height="338" src="//www.youtube.com/embed/dWhIiONkR5g" frameborder="0" allowfullscreen></iframe> 

Plot Directional Heat Flux along Path

 <iframe width="600" height="338" src="//www.youtube.com/embed/HQbG9tcdf4g" frameborder="0" allowfullscreen></iframe> 

Export Data to Excel

 <iframe width="600" height="338" src="//www.youtube.com/embed/N3gyjuSiyow" frameborder="0" allowfullscreen></iframe> 

Overall Heat Flux Crossing Boundary Surfaces

 <iframe width="600" height="338" src="//www.youtube.com/embed/fPdLGq7U7iM" frameborder="0" allowfullscreen></iframe> 

The overall heat fluxes are reported as "reactions" at boundaries in ANSYS. This terminology comes from analogy with structural mechanics and is explained in the video below.

 <iframe width="600" height="338" src="//www.youtube.com/embed/fPdLGq7U7iM" frameborder="0" allowfullscreen></iframe> 

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You then have the option to export this into a text file or an Excel file.  Either will work, but for this tutorial we have exported to excel.

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Probe Temperature

The following video shows a couple of ways to probe the temperature in the solution domain. If the video doesn't appear below, try reloading the webpage.

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<iframe width="600" height="338" src="//www.youtube.com/embed/Tdh7aT1jHwI" frameborder="0" allowfullscreen></iframe>

Directional Heat Flux along Y=0m line

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Similar to the Temperature inserted along the first path, now insert Directional Heat Flux results along Path 2. (Right Click) Solution > Insert > Thermal > Directional Heat Flux. Choose Path for the Scoping Method, set Path 2 for the Path and Y axis for Orientation, as seen below.

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Click Solve,  , and ANSYS will find the Directional Heat Flux on the line y=0m as a function of x position.  We would like to find the total heat flux through the bottom by integrating the flux along that boundary. To do this we will export the data to MATLAB and perform a numerical integration.  Right click in the tabular data displayed in the lower righthand corner of the screen.  Select all (Ctrl+A), right-click and select Export.  Save the file as "qy_bot.txt" in your MATLAB working directory.

Next, open MATLAB and use the following code to integrate along the path:

clear all; clc;
qy_bot = dlmread('qy_bot.txt', '', 'B2..C50');
qy_bot_tot = trapz(qy_bot(:,1),qy_bot(:,2));

The dlmread function is used to read the data from the text file, while the trapz function performs numerical integration using trapezoids.  The variable 'qy_bot_tot' calculated in MATLAB represents the total dimensionless heat flux through the bottom, y=0 line.

Save

Save the project now.
 

Go to Step 7: Verification & Validation

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