International Research Journal of Engineering and Technology (IRJET)
e-ISSN: 2395 -0056
Volume: 04 Issue: 04 | Apr -2017
p-ISSN: 2395-0072
www.irjet.net
A STUDY & ANALYSIS OF THERMOELECTRIC REFRIGERATION SYSTEM WITH ENVIRONMENT Ankit Dubey1, Umanand Kumar Singh2, Manish Rathore3 123Dr.
APJ Abdul Kalam UIT, Jhabua
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Abstract - There are various sources which cause ozone
depletion out which conventional R&AC systems has a major role. R&AC contributes for about 29.6% of the total ozone depletion[1]. Ozone in the stratosphere has a beneficial role as it blocks UV radiation from the sun. Highly energetic UV radiation called UV-C (wavelength 280 nm) is absorbed by the ozone molecules. UV-B radiation (wavelength 280 – 325 nm) is also absorbed. The ozone layer acts as a shield for us from very harmful UV rays. Exposure to UV rays causes skin cancer, damages crops, affects cellular DNA, impairs photosynthesis and harms ocean life. Observed and projected decreases in ozone have generated worldwide concern leading to adoption of the Montreal Protocol that bans the production of CFCs, halons and other ozone-depleting chemicals such as carbon tetrachloride and trichloroethane. R&AC has a vast scope. But the conventional technology using the heat carrying fluids viz. refrigerants (CFCs and HCFCs) renders it unsafe and very harmful. So on the basis of Peltier module Thermoelectric Refrigerator is used for cooling and refrigeration. Thermoelectric cooling [5] technology proves to be a promising alternative over the conventional R&AC. This technology eliminates the use of refrigerants thereby overcoming the main disadvantage of conventional system i.e. ozone depletion and global warming, Long life than conventional cooling, with mean time between failures (MTBF) exceeding, Able to operate in any orientation , excellent cooling alternative to vapour compression coolers for systems that are sensitive 100,000 hours. Key Words: Peltier module, Heat Sink, Enclosure. 1.INTRODUCTION Development of air conditioning and refrigeration is one of the greatest engineering achievements of the 20th century. The efficiencies of both living and non-living beings depend to a great extent on the surrounding physical environment. The nature keeps conditions in the physical environment in a dynamic state, at times changing it from one extreme to the other. The highly efficient and widespread conventional R&AC technology was doing flourishing business producing refrigeration and air conditioning units at its peak. However in 1974, it was discovered that the CFC and HCFC gases, which were the most common refrigerants at that time, deplete the ozone © 2017, IRJET
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Impact Factor value: 5.181
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layer if released into the atmosphere. Thus, the mechanism of ozone layer depletion by the CFC’s and HCFC’s was identified. In 1985, an ozone hole was observed and this provided the proof that ozone layer was depleting. Contribution of conventional r&ac in ozone depletion There are various sources which causes ozone depletion out which conventional R&AC systems has a major role. R&AC contributes for about 29.6% of the total ozone depletion. This is a considerably large amount which must be reduced in order to protect the ozone layer CFCs and HCFCs used as heat carrier fluids in conventional system deplete ozone layer and increases global warming. Photo dissociation of halocarbon refrigerants in stratosphere cause ozone layerdepletion. Following chart shows the contribution of R&AC among other sources in harming the Ozone layer.
Fig.1-sources that harm the protective ozone layer Ozone layer Ozone is present in the atmosphere from the ground up to 50 km altitudes and higher. However, most of the ozone is in a region of the atmosphere called the stratosphere, between 15 and 30 km above the surface of the Earth. This ozone rich region is commonly called the ‘Ozone Layer’. Ozone in the stratosphere has a beneficial role as it blocks UV radiation from the sun. Highly energetic UV radiation called UV-C (wavelength 280 nm) is absorbed by the ozone molecules. UV-B radiation (wavelength 280 – 325 nm) is also absorbed. The ozone layer acts as a shield for us from very harmful UV rays. Exposure to UV rays causes skin cancer, damages crops, affects cellular DNA, impairs photosynthesis and harms ocean life. Without the presence of ozone layer living things do not have long time to live on the Earth. ISO 9001:2008 Certified Journal
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