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HOW REFRIGERATOR WORKS ?

Jacob Perkins, a Massachusetts inventor, developed the first compression machine in 1834. Ferdinand Carre, a French engineer, developed the first absorption system using ammonia during 1850's. Karl von Linde of Germany introduced the first successful compression system using ammonia between 1873 and 1875. This system is known as "Refrigerator". Refrigerators have become necessities in modern society. Refrigerators allow for the preservation of food that would otherwise spoil. The fundamental reason for having a refrigerator is to keep food cold. This is accomplished by keeping food at relatively low temperatures, so that bacterial growth is slowed. The basic idea behind refrigeration is to slow down the activity of bacteria (which all food contains) so that it takes longer for the bacteria to spoil the food. Every single refrigerator is made up of at least four key parts:

Compressor : A pump which compresses refrigerant gas, and consequently heats the gas.
Heat-exchanging pipes (also known as a condenser) : Serpentine or coiled set of pipes outside the unit or inside the unit.
Expansion valve
Refrigerant : A chemical substance used as a fluid in a refrigeration system. There are many different types of fluid used, depending on the system design. Most commonly used are hydrofluorocarbons (HFCs) and hydrocarbons (HCs).

Many industrial installations use pure ammonia as the refrigerant. Pure ammonia evaporates at -27 degrees Fahrenheit (-32 degrees Celsius).

HOW OLD REFRIGERATOR WORKS ?

At the back or bottom of an older refrigerator, a long thin tube that loops back and forth. This tube is connected to a pump, which is powered by an electric motor. Inside the tube is Freon, a type of gas. Freon is the brand name of the gas. This gas, chemically is called Chloro-Flouro-Carbon or CFC. This gas was found to hurt the environment if it leaks from refrigerators. So now, other chemicals are used in a slightly different process . CFC starts out as a liquid. The pump pushes the CFC through a lot of coils in the freezer area. There the chemical turns to a vapor. When it does, it soaks up some of the heat that may be in the freezer compartment. As it does this, the coils getting colder and the freezer begins to get colder. In the regular part of your refrigerator, there are fewer coils and a larger space. So, less heat is soaked up by the coils and the CFC vapor. The pump them sucks the CFC as a vapor and forces it through thinner pipes which are on the outside of the refrigerator. By compressing it, the CFC turns back into a liquid and heat is given off and is absorbed by the air around it. That's why it might be a little warmer behind or under your refrigerator. Once the CFC passes through the outside coils, the liquid is ready to go back through the freezer and refrigerator over and over.

How new Refrigerator Works ?

Gas is drawn at low pressure and low temperature through a line. The gas is compressed using electricity to a higher pressure and its temperature rises (just like a bicycle pump which gets warmer when you are pumping up a tyre). It is then transferred to a condenser where the heat is removed and the gas begins to condense into a liquid. The heat is released via cooling fins on the back of the fridge unit. The liquid then goes through an expansion device where its pressure is suddenly lowered, it expands and some of the liquid turns very quickly into a vapour. This change of state has a cooling effect. Now the cold vapour and liquid are able to cool the air in the cabinet of the refrigerator through an evaporator. The liquid absorbs the warmth from the air inside the refrigerator and turns back into a low temperature gas, at low pressure. It now starts its journey again through the compressor.

HOPE THAT WAS INTERESTING .

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