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ABSTRACT This work investigates the result of an experimental study carried out todetermine the performance of domestic refrigerator when a propane-butane mixture isl i q u e f i e d p e t r o l e u m g a s ( L P G ) w h i c h i s l o c a l l y a v a i l a b l e a n d comprises 24.4% p r o p a n e , 5 6 . 4 % b u t a n e a n d 1 7 . 2 % i s o b u t e n e w h i c h i s v e r y f r o m c o m p a n y t o company. The LPG is cheaper and possesses an environmental friendly nature with noozone deple
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   ABSTRACT This work investigates the result of an experimental study carried out todetermine the performance of domestic refrigerator when a propane-butane mixture isliquefied petroleum gas (LPG) which is locally available and comprises 24.4% propane, 56.4% butane and 17.2% isobutene which is very from company tocompany. The LPG is cheaper and possesses an environmental friendly nature with noozone depletion  potential (ODP). It is used in world for cooking purposes. The variousmethods of refrigeration on the basis of standard refrigerant discussed. He refrigerator used in the present study is of medium size with a gross capacity of 125 litre and isdesigned to work on LPG. The performance parameters investigated is therefrigeration effect in certain time. The refrigerator worked efficiently when LPG wasused as refrigerant instead of CFC 12. The evaporator temperature reached -5 ºC withand an ambient temperature of 12 ºC. Also from the experiment which done inatmospheric condition, we can predict the optimum value of cooling effect with thesuitable operating condition of regulating valve and capillary tube of the system. Theresults of the present work indicate the successful use of this propane-butane mixtureas an alternative refrigerant to CFC 12 in domestic refrigerant. 1  1.1 INTRODUCTION The term ‘refrigeration’ in a broad sense is used for the process of removing heat(i.e. cooling) from a substance. It also includes the  process of reducing andmaintaining the temperature of a body below the general temperature of itssurroundings. In other words, the refrigeration means a continued extraction of heatfrom a body, whose temperature is already below the temperature of its surroundings.For example, if some space (say in cold storage) is to be kept at -2 ºC, wemust continuously extract heat which flows into it due to leakage through the wallsand also the heat, which is brought into it with the articles stored after the temperatureis one reduced to -2 ºC. Thus in a refrigerator, heat is virtually being pumped from alower temperature to a higher temperature. According to second law of thermodynamics, this process can only be performed with the aid of some externalwork. It is thus obvious, that supply of power (say electrical motor) is regularlyrequired to drive a refrigerator. Theoretically, the refrigerator is a reversed heatengine, or a heat pump which pumps heat from cold body and delivers to a hot body.The substance which works in a heat pump to extract heat from a cold body and todeliver it to a hot body is called refrigerant.When people hear the word refrigeration they immediately think of therefrigerator in their kitchen. However there are actually quite a few different kinds of refrigeration out three and they each have their own methods of functioning. One particular type of refrigeration is industrial refrigeration. This type of refrigeration istypically used for cold storage, food  processing, and chemical processing.The equipment is very large and made of industrial stainless steel. Industrialrefrigeration, which frequently uses ammonia refrigeration to maintain temperature, is2 necessary for computer, foodstuffs, blood, vaccines, and quite a few other goods thatmust maintain a constant and steady temperature at all times. Temperatures that aretoo high or too low may spoil certain goods or ruin them. As a result industrialrefrigeration is especially important maintaining temperature is as well. Sincetemperature is so important into industrial refrigeration companies offering thisservice must pay attention at all times to the temperature of the industrial refrigerators. 1.2 HISTORY OF REFRIGERATION  The refrigeration system is known to the man, since the middle nineteenthcentury. The scientist, of the time, developed a few stray machines to achieve some pleasure. But it paved the way by inviting the attention of scientist for proper studiesand research. They were able to   build a reasonably reliable machine by the end of nineteenth century for the refrigeration jobs. But with the advent of efficient rotarycompressors and gas turbines, the science of refrigeration reached its  present height.Hebrews, Greeks, and Romans placed large amounts of snow into storage pitsdug into the ground and insulated with wood and straw. The ancient Egyptians filledearthen jars with boiled water and put them their roofs, thus exposing the jars to the night’s cool air. In India, evaporating cooling was employed. When a liquid vaporisesrapidly, it expands quickly. The rising molecules of vapour abruptly increase heir kinetic energy and this increase is drawn from the immediate surroundings of thevapour. These surroundings are therefore cooled.The intermediate stage in the history of cooling foods was to add chemicals likesodium nitrate or  potassium nitrate to water causing the temperature to fall. Cooling wine via above method was recorded in 1550, as were the words “to ref  rigerate”.3  Cooling drinks came into vogue by 1600 in France. Instead of cooling water atnight, people rotate long-necked bottles in water in which saltpetre had beendissolved. This solution could be used to produce very low temperature and to makeice. By the end of the 17 th century, iced liquors and frozen juices were popular inFrench society. The first known artificial refrigeration was demonstrated by William Cullen atthe University of Glasow in 1748.Beginning in the 1840, refrigerated cars were used to transport milk and butter.By 1860, refrigerated transport was limited to mostly seafood and dairy products. Therefrigerated railroad car was  patented by J.B.Sutherland of Detroit, Michigan in 1867.He designed an insulated car with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity, controlled bythe use of hanging flaps that created differences in air temperature.Brewing was the first activity in the northern states to use mechanicalrefrigeration extensively, beginning with an absorption machine used by S. Liebmann’s  Sons Brewing Company in Brooklyn, New York in 1870.commercial refrigeration was primarily directed at breweries in the 1870 and 1891,nearly every brewery was equipped with refrigerating machines.Natural ice supply became an industry unto itself. By 1879, there were 35commercial ice plants in America, more than 200 a decade later, and 2,000 by 1909. No pond was safe from scraping for ice production, not even Thoreau’s Walden Pond, where 1,000 tons of ice was extracted each day in 1847.However, as time went on, ice, as a refrigeration agent, became health   problem.Says Bern Nagengast, co-author of Heat and Cold: Mastering the Great Indoors(published  by the American Society of Heating, Refrigeration and Air-conditioning Engineers), “Good sources were harder and harder to find. By the 1890’s, natural ice  became a problem because of 4
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