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Refrigerator

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What is Refrigerator?

A refrigerator is a machine for keeping thing cold. It is sometimes called a fridge. People put food and drinks in it, to keep those items cold or good for a longer time. A refrigerator has a heat pump. It takes heat away from the air inside the fridge. The heat gets added to the air outside. The heat pump is usually driven by an electric motor.

There are also ice boxes available that do not use electricity because they are filled with ice to provide the colder temperature. The ice can keep things cold until the ice melts. These ice boxes can be taken on camping trips. Sometimes they are called coolers. Refrigerator-sized ice boxes were used before electricity was available.

Smaller versions of the popular refrigerator are also used. These are mainly used in hotels, college dorm rooms; they are also popular in Africa, and known by the name of micro fridges.

 

History of Refrigerator:-

The first appliance that could reasonably be called a refrigerator was demonstrated by William Cullen at the University of Glasgow in 1748.

In 1805, the American inventor, Oliver Evans, designed a machine based on vaper-compression, but he never built it.

In 1834 Jacob Perkins did build a refrigeration unit by modifying Evans’ design and filed the he first legal patent for refrigeration using vaper-compression.

In 1841, John Gorrie, a doctor from Florida, modified Evans’ idea further and produced a machine which was patented in 1851.

A similar appliance was patented by Alexander C. Twining in 1853. This was invented by Fred W. Wolf of Fort Wayne, Indiana in 1913.

Then, in 1914, engineer Nathaniel B. Wales of Detroit, Michigan, introduced an idea for a practical electric refrigeration unit, which later became the basis for the Kelvinator.

A self-contained refrigerator, with a compressor on the bottom of the cabinet was invented by Alfred Mellowes in 1916. Mellowes produced this refrigerator commercially but was bought out by William C. Durant in 1918, which started the Frigidaire Company to mass-produce refrigerators.

In the US, the first mass market refrigerator was the General Electric “Monitor-Top” introduced in 1927. In the 1950s and 1960s there were further advances, such as automatic defrosting and automatic ice making. Over the next few decades, refrigerator operation became even more efficient, and continues to advance year by year.

 

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Effects of Refrigerator on human health:-

It is commonly known that hot environment are where bacteria thrive the most, but there are bacteria that can actually thrive in cold conditions. Your refrigerator can be a breeding environment for microorganisms to thrive. Psychrophilic bacteria that can grow in cold environment same as the refrigerator temperature. This group of bacteria can cause food spoilage and poisoning. They are harmful to human health. In view of this harmful effect, it is appropriate the refrigerator is always clean and free from microorganisms.

When the refrigerator is not in a clean state, it creates an enabling habitat for these bacteria and will contaminate the foods that are stored.  When you eat food contaminated by bacteria, you are also directly taking in the bacteria. When the bacteria get into your system, they become pathogenic. Even if the bacteria didn't get into your system, these bacteria can release harmful toxins into food thus causing serious illness.

 

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Effects of Refrigerator on environment:-

Due to their stability in the atmosphere, CFCs as well as HCFCs and HFCs are often very effective greenhouse gases. The GWP factor is used to reflect their impact on global warming.

Ozone Depletion Potential, ODP Refrigerants containing chlorine or bromine contribute to the breakdown of the ozone layer. However, the CIO molecule is unstable. It breaks down and reacts with ozone molecules repeatedly until a more stable compound is created.

The GWP is the ratio of the warming caused by a substance to the warming caused by a similar mass of carbon dioxide. When using GWP values from different sources, it is important to consider that the values may differ due to different integration times or calculation models.

 

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