[FINAL UPDATE] Multi-stage Thermoelectric Cooler with Heat Pipe Attachment for Improved Condensing Performance

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This design is an additional component to the existing design that improves the condensation performance by making the wall cooler. More detail on the working principle can be read on the PDF attached with Adobe Acrobat DC.The design utilizes multi-stage thermoelectric cooler (TEC). The cool side of the first stage TEC becomes the hot side of the next stage. By theory, the temperature difference between the sides will always be the same, thus by reducing the temperature of the hot side will make the other side cooler. This concept has been tested by researcher (Putra et al., 2010) which creates a device to replace the cryogenic surgery for cervical cancer, in which the device successfully achieve 177K and in fact has been used in a hospital in Indonesia. The paper is on the attachment. This cold side will then absorb the heat by connecting the cold side to a base plate that is attached to a heat pipe which is coiled around the water trap. Reliability of the TEC is also very high based on the research paper by Choi (2011) and will continue to improve. The device is attached by a clamp that is tightened using bolts and nuts, similar to a bicycle seat clamp.The casing will hold the TEC in place and heat shield (polyurethane) will be wrapped around the heat pipe and casing so the heat absorbed from the environment will be minimized and ensuring the majority of heat absorbed is from the water trap. Improvement can also be made by attaching the hot side of the first stage TEC with a finned copper/aluminium so that it will dissipate heat faster and became colder.Pros:- No modification needs to be done on the existing design.- No additional point of leakage is produced by the attachment- Inexpensive cooling module (TEC) and easily maintained. Maintenance cost will only comes from replacing the TEC $5-10 each that can last for ~4000 cycles (Choi, 2011). Other components do not need any maintenance. - Proof of concept that coldest temperature attained could reach 177K (-96 degree Celcius) and thus possibly attain PPMV level of 10 ppm. Dew point of 10 ppm is around -30 degree Celcius, which corresponds to 94%RH, very saturated. So the power input of the TEC should be less than on the Putra et al. (2010) experiment which is around 12V and 2.5A. Other option could be reducing the number of stages.- Does not need any micro-machining because no small holes present or any important details required, and thus making it cheap to mass manufactureCons:- Additional power is needed, although it is relatively low (6-staged, 6V-1.5A, so in total will be around 100 Watt to achieve -73 degree Celcius from Putra et al. (2010) experiment)- Needs cooling time for several minutes before it finally achieves steady state operating temperature - Dimension exceeds the 26mm criterion. On other directions the dimension still comply on the requirements mentioned.