According to sources students of IIT Madras have developed a refrigerator that can achieve a lowest temperature of -200o C by using a single stage vapour compression refrigerator that uses a compressor regularly used in domestic refrigerators and ACs. Reportedly this system was operated non-stop at -200o C for three months non-stop.
Using the conventional cascade refrigeration system, temperatures as low as -110 degree C can be easily achieved. However, in the new system developed by engineers at IIT-Madras, three refrigerators were connected in a series and they worked in sync to bring down the temperature in steps. Professor Venkatarathnam explains that the main disadvantage of this technique to bring reduction in temperature is that each stage requires one compressor and a few heat exchangers. This makes the overall circuit complex and expensive as well.
Conventional refrigeration systems use a single liquid coolant that absorbs heat and becomes vapour at a constant temperature. The new technology developed at IIT uses a mixture of coolants where the conversion of liquid to vapour occurs over a range of temperatures, in an internal heat exchanger. The heat exchangers used by the team are capable of working at very large temperature difference of about 200 degree C, unlike the conventional systems in which heat exchangers work at one temperature. Prof. Venkatarathnam mentions that most of the applications won’t need -196 degree C.
No comments:
Post a Comment