列车空调制冷机组文献翻译

1、FreonBy Mary BellisRefrigerators from the late 1800s until 1929 used the toxic gases, ammonia (NH3, methyl chloride (CH3Cl, and sulfur dioxide (SO2, as refrigerants. Several fatal accidents occurred in the 1920s because of methyl chloride leakage fromrefrigerators . People started leaving their refr

2、igerators in their backyards. A collaborative effort began between three Am erican corporations, Frigidaire, General Motors and DuPont to search for a less dangerous method of refrigeration.In 1928, Thomas Midgley, Jr. aided by Charles Franklin Kettering invented a "miracle com pound" call

3、ed Freon. Freon represents several different chlorofluorocarbons, or CFCs, which are used in commerce and industry. The CFCs are a group of aliphatic organic com pounds containing the elements carbon and fluorine, and, in many cases, otherhalogens (especially chlorine and hydrogen. Freons are colorl

4、ess, odorless, nonflammable, noncorrosive gases or liquids.Side Note: Charles Franklin Kettering invented the first electric automobile ignition system. He was also the vice-president of the General Motors Research Corporation from 1920 to 1948. General Motors' scientist, Thomas Midgley invented

5、 leaded (ethyl gasoline .Thom as Midgley was chosen by Charles Franklin Kettering to head the research into the new refrigerants. Frigidaire was issued the first patent, US#1,886,339, for the formula for CFCs on December 31, 1928.In 1930, General Motors and DuPont formed the Kinetic Chemical Company

6、 to produce Freon. By 1935, Frigidaire and its competitors had sold 8 million new refrigerators in the United States using Freon made by the Kinetic Chemical Company. In 1932, the Carrier Engineering Corporation used Freon in the world's first self-contained home air conditioning unit, called an

7、 "Atmospheric Cabinet".Side Note: The trade name Freon ® is a registered trademark belonging to E.I. du Pont de Nemours& Company (DuPont.Because Freon is non-toxic, it eliminated the danger posed by refrigerator leaks. In just a few years, compressor refrigerators using Freon woul

8、d become the standard for almost all hom e kitchens. In 1930, Thomas Midgley held a demonstration of the physical properties ofFreon for the American Chemical Society by inhaling a lung-full of the new wonder gas and breathing it out onto a candle flame, which was extinguished, thus showing the gas&

9、#39;s non-toxicity and non-flammable properties. Only decades later did people realize that such chlorofluorocarbons endangered the ozone layer of the entire planet.Side Note: CFCs, or Freon, are now infamous for greatly adding to the depletion of the earth's ozone shield. Leaded gasoline is als

10、o a major pollutant, and Thomas Midgley secretly suffered from lead poisoning because of his invention, a fact he kept hidden from the public.Thom as Midgley discoveries ranged from a way of getting salt into popcorn before it was popped, to a method for treating the contents of a swimming pool so t

11、hat people could swim farther underwater.The History of the Refrigerator and Freezers Before mechanical refrigeration systems were introduced, people cooled their food with ice and snow, either found locally or brought down from the mountains. The first cellars were holes dug into the ground and lin

12、ed with wood or straw and packed with snow and ice: this was the only means of refrigeration for most of history.Refrigeration is the process of removing heat from an enclosed space, or from a substance, to lower its temperature. A refrigerator uses the evaporation of a liquid to absorb heat. The li

13、quid, or refrigerant, used in a refrigerator evaporates at an extremely low temperature, creating freezing temperatures inside the refrigerator. It's all based on the following physics : - a liquid is rapidly vaporized (through compression - the quickly expanding vapor requires kinetic energy an

14、d draws the energy needed from the immediate area - which loses energy and becomes cooler. Cooling caused by the rapid expansion of gases is the primary means of refrigeration todayThe first known artificial refrigeration was demonstrated by William Cullen at the University of Glasgow in 1748. Howev

15、er, he did not use his discovery for any practical purpose. In 1805, an American inventor, Oliver Evans, designed the first refrigeration machine. The first practical refrigerating machine was built by Jacob Perkins in 1834; it used ether in a vapor com pression cycle. An American physician, John Go

16、rrie, built a refrigerator based on Oliver Evans' design in 1844 to make ice to cool the air for his yellow fever patients. German engineer Carl von Linden, patented not a refrigerator but the process of liquifying gas in 1876 that is part of basic refrigeration technology.Side Note: Improved re

17、frigerator designs were patented by African American inventors,Thomas Elkins (11/4/1879 U.S. patent #221,222 and John Standard (7/14/1891 U.S. patent #455,891.Refrigerators from the late 1800s until 1929 used the toxic gases ammonia (NH3, methyl chloride (CH3Cl, and sulfur dioxide (SO2 as refrigeran

18、ts. Several fatal accidents occurred in the 1920s when methyl chloride leaked out of refrigerators. Three American corporations launched collaborative research to develop a less dangerous method of refrigeration; their efforts lead to the discovery ofFreon . In just a few years, compressor refrigera

19、tors using Freon would became the standard for almost all home kitchens. Only decades later, would people realize that these chlorofluorocarbons endangered the ozone layer of the entire planet.One hundred years ago, refrigeration engineers began to search for a permanent solution to the problem of l

20、eaky refrigeration systems.From the History Channel, a cool, simple outline of the "History of the Refrigerator"."At some point, perhaps in fourteenth century China or seventeenth century Italy, it was discovered that the evaporation of brine (salt water absorbed heat and therefore a

21、container placed in brine would stay cold." This short essay discusses the highlights of refrigerator history.One hundred years ago, refrigeration engineers began to search for a permanent solution to theproblem of leaky refrigeration system s. From the History Channel, a cool, simple outline o

22、f the "History of the Refrigerator". "At some point, perhaps in fourteenth century China or seventeenth century Italy, it was discovered that the evaporation of brine (salt water absorbed heat and therefore a container placed in brine would stay cold." This short essay discusses

23、the highlights of refrigerator history. A mixture called chemogene (consisting of petrol ether and naphtha was patented as a refrigerant for vapor compression systems in 1866. Carbon dioxide was introduced as a refrigerant in the same year . The term "refrigerator" was coined by a Maryland

24、 engineer , Thomas Moore, in 1800. Moore's device would now be called an "ice box" - a cedar tub, insulated with rabbit fur,filled with ice, surrounding a sheetm etal container for transporting butter from rural Marylandto Washington, DC.HowRefrigerators Work , written by Marshall Brai

25、n of How Stuff Works. The Freezing Process Freezing food involves lowering its temperature to below 0º C, resulting in the gradual conversion of the water present in the food into ice. The History of Air ConditioningIn 1902, only one year after Willis Haviland Carrier graduated from Cornell Uni

26、versity with a Masters in Engineering, the first air (temperature and humidity conditioning was in operation, making one Brooklyn printing plant owner very happy. Fluctuations in heat and humidity in his plant had caused the dim ensions of the printing paper to keep altering slightly, enough to ensu

27、re a misalignment of the colored inks. The new air conditioning machine created a stable environment and aligned four-color printing became possible. All thanks to the new employee at the Buffalo Forge Company, who started on a salary of only $10.00 per week.The 'Apparatus for Treating Air'

28、(U.S. Pat# 808897 granted in 1906, was the first of several patents awarded to Willis Haviland Carrier . The recognized 'father of air conditioning' is Carrier , but the term 'air conditioning' actually originated with textile engineer, Stuart H. Cramer . Cramer used the phrase '

29、air conditioning' in a 1906 patent claim filed for a device that added water vapor to the air in textile plants - to condition the yarn.In 1911, Willis Haviland Carrier disclosed his basic Rational Psychrometric Form ulae to the American Society of Mechanical Engineers. The formula still stands

30、today as the basis in all fundamental calculations for the air conditioning industry. Carrier said he received his 'flash of genius' while waiting for a train. It was a foggy night and he was going over in his mind the problem of temperature and humidity control. By the tim e the train arriv

31、ed, Carrier had an understanding of the relationship between temperature, humidity and dew point.Industries flourished with the new ability to control the temperature and humidity levels during and after production. Film, tobacco, processed meats, medical capsules, textiles and other products acquir

32、ed significant improvem ents in quality with air conditioning. Willis and six other engineers formed the Carrier Engineering Corporation in 1915 with a startingcapital of $35,000 (1995 sales topped $5 billion. The company was dedicated to improving air conditioning technology.In 1921, Willis Havilan

33、d Carrier patented the centrifugal refrigeration m achine. The 'centrifugal chiller' was the first practical method of air conditioning large spaces. Previous refrigeration machines used reciprocating-compressors (piston-driven to pump refrigerant (often toxic and flammable ammonia throughout the system . Carrier designed a centrifugal-com pressor similar to the centrifugal turning-blades of a water pump. The result was a safer and more efficient chiller.Cooling for human comfort, rather than industrial nee