Refrigerators have earned their place as one of the most significant inventions in Human History. The ability to maintain a lower temperature through artificial means has led to the rise of many industries like beverages, chemicals, and even medicines. Even the personal lives of people have changed for the better.
However, do you know how this marvelous piece of machinery operates? Thermodynamics has stated that it is impossible to remove heat without external work and this is the principle of a fridge. Read on to find out more about the working of a refrigerator.
Working Principle of a Refrigerator
When gases are compressed, they inevitably get hotter because they occupy a lower volume and the molecules frequently collide with each other. This causes the heat energy to increase. When the gas expands, it occupies a higher volume and as a result, the heat energy is spread over a larger space, thus lowering the temperature.
Moreover, when substances at different temperatures are brought in contact, the heat will flow from the hotter body to the colder one. In a refrigerator, a special gas known as the Refrigerant is used for circulation.
Working Parts of a Refrigerator
There are some major components in a Refrigerator and we will be looking at them one by one.
- Compressor- The compressor is responsible for circulating the refrigerant throughout the fridge. It also compresses the refrigerator and thereby makes it hot. You can find it at the backside of the fridge and it features an electric motor. The compressor consumes a fair bit of electricity.
- Condenser- It is the copper tubes situated at the rear section of the fridge. The condenser absorbs heat from the refrigerant and therefore is quite hot to touch. Here, the refrigerant is condensed from gas to liquid.
- Evaporator- The evaporator is inside the fridge and it is here where the refrigerant absorbs heat from the foodstuff. Usually, it is made of Aluminum or Copper Tubing.
- Refrigerant- It is a cooling liquid/gas that is pumped throughout the fridge. Initially, CFCs were used as a refrigerant but now they have been substituted for R12 and R134A.
- Capillary Tube- This is a thin tube where the refrigerant expands. As a result, the pressure is decreased. The low-pressure refrigerant is then sent to the evaporator.
- Thermostat- The thermostat is responsible for controlling the temperature in the interior. It monitors the temperature and then switches the compressor on/off. When the temperature is quite cold, the compressor is turned off and vice versa.
- Defrost System- It removes all the ice that gets accumulated in the freezer compartment. It can be achieved manually through the thermostat button or by using an electric heating mechanism.
- Diffuser- Diffuser is responsible for moderating the cold airflow from the freezer to the refrigerator. There is a temperature sensor, using which you can control the thermostat. When the diffuser feels that air is quite warm, it opens the vent situated amongst the compartments.
Working of a Refrigerator
Basically, the refrigerant is circulated inside while having a phase change from gas to liquid and vice versa. This causes heat to be absorbed from the food and produces a feeling of coolness. After the evaporation, the pressure on the refrigerant is decreased by passing it through a capillary tube.
To change the refrigerant back to liquid, it is passed into the compressor where the pressure is increased. The hot gas from the compressor is sent to the condenser where it is cooled again and reverts back to the liquid form. Thus, it re-enters the evaporator and the whole process starts all over again.
- The compressor compresses the vapor, thereby increasing pressure and temperature and it is sent to the condenser coils.
- In the condenser, the refrigerant becomes a liquid.
- The high-pressure liquid refrigerant flows through the expansion valve and cools down eventually.
- The refrigerant flows through the evaporator coils where it absorbs heat from the interior of the fridge and thus cools the food.
We hope this article would have helped you to understand in brief the mechanism of a refrigerator. The refrigerator is undoubtedly an essential part of a common house and it is essential to have a basic understanding of its composite parts. For any queries, do contact us.