We headed down to Sim Lim Square on Thursday to buy various secondhand fans and CPU heatsinks of different sizes and shapes so that we could test the different types and see if they corroborated with our theoretical simulations. From our set-up, we expected a decrease in temperature of ambient air to cold air by about 6°C.
The next day, we did the set-up according to the preliminary design from our COMSOL simulations and tested the setup both inside the MnT lab and outside.
On that day, the MnT lab had an ambient temperature of 24°C while the outdoor area was at 29°C. We measured the temperature of the air exiting our model on both the hot side and the cool side, and compared the temperature change between the exiting air and ambient temperatures. We found that temperatures decreased by 1.5°C when we took the set-up outside, indicating that using one Peltier plate to cool the air was insufficient. The draft from the fans was also inadequate. Based on our calculations, an estimated 137W cooling capacity is required to cool 40cfm of air by 6°C. This requires more than 4 TEC1-12706 modules and a much smaller volumetric capacity than our fans were already providing.
After this, we carried out some minor experiments where we varied the voltage and current of the Peltier plate to see the effect on the temperature of the hot and cold side of the plate. From this, we were able to optimise the voltage and current at 12V and 4A.