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Due to time constraints, we were unable to alter pot quantity or placement and instead measured change of convection over varying temperature. During the experiment, we had a thermal sink of a black pot with 5 lbs. of water in the center of the oven. The field of view covered the right side of the oven from the bottom black plate to the pot on the left side. In order for the camera to be able to view inside the oven from the front, the plywood door had to be removed and a piece of glass was duct taped into place. Additionally, the back of the oven is covered with reflective sheet metal. This had to be covered with a piece of cardboard duct taped into place. We assume these changes had a negligible effect on oven performance.
Figure 1 - PIV schematic
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Figure 2 - Picture of PIV setup in DeFrees lab.
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Figure 4 - Front view of PIV experiment being run.
Figure 5 - Top view of PIV experiment being run.
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We also note that these PIV results generally agree with the heating mechanism isolation tests. Of the three mechanisms, we can only expect that energy gained from radiation will remain constant from the beginning of heating through all temperatures. As the black plate gets hotter relative to the pot, we expect that conduction's role in heating would increase. And finally, as convection cell strength increases (as is seen in PIV) we expect the role of convection to also increase. While the contribution of the three mechanisms was more uniform across temperatures than we might think, there was a definite decrease in radiation's contribution at high temperatures.
Figure 7 - Vector map of mean displacements at 30°C.
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Figure 8 - Vector map of mean displacements at 50°C.
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Figure 9 - Vector map of mean displacements at 70°C.
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