In the thesis, we used an IR camera to observe the freezing process of droplets of three different volumes, 1 μl, 10 μl and 50 μl, on a hydrophobic and a reference surface. By varying the electric current, we varied the cooling power of the Peltier element and thus the rate at which the surface cooled or the water droplet froze. We found that on average the droplet cooling time on the hydrophobic surface is 85 s and on the reference surface 52 s, which is 38% longer cooling on the hydrophobic surface and the whole freezing process takes on average 26% longer on the hydrophobic surface compared to the reference surface. The volume of the droplets also affects the freezing time, as larger droplets take longer to freeze. On average, the freezing process was 356% longer for 10 μl droplets and 1077% longer for 50 μl droplets compared to 1 μl droplet. The IR camera was also used at 200 Hz to record the recalescence of a 10 μl droplet.
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