1. Welcome to our Presentation

2. Group no - 5 1.Saykat Islam ................... – ID# 15107018
2.Fazle Rabb……………………..– ID#
3.Md.Sihan Ahmed Simoon…– ID#
4.Md. Irfan Uddin ……………… – ID#
5.Md. Yaqub Arafat …………… – ID#

3. Refrigeration system and modern refrigerators.
First general Electric "Monitor-Top" refrigerator, introduced in 1927.
Latest glass door refrigerator

4. what is refrigeration
Definition of refrigeration: The process of keeping an item below the room temperature  in a system, its freeze.
The history of artificial refrigeration began when Scottish professor William Cullen designed a small refrigerating machine in Cullen used his refrigerator  diethyl ether. The experiment even created a small amount of ice, but he had no practical application at that time.

5. Use of refrigeration process in machines
Now a days Refrigerator is a most common machine in our country.
. The first cooling systems for food involved using ice. Artificial refrigeration began in the mid-1750s, and developed in the early 1800s.
Now lets know about refrigerators.

6. History of refrigerators
Before the invention of the refrigerator, icehouses were used to cool storage for most of the year. Which was packed with snow and ice during the winter season, It was actually natural process.
The first practical vapor compression refrigeration system was built by James Harrison, He used compression system ether, alcohol and ammonia .
 A self-contained refrigerator, with a compressor was invented by Mellowes in 1916. .

7. The first refrigerator of general electric monitor.
This refrigerator used sulfur dioxide as refrigerating medium which was harmful for eyes. and skin burn or methyl format which was highly flammable.
The problem was solved by Freon which was invented in 1920.

8. Main components of Refrigerators
1. compressor
Hermetic Piston Refrigerator R600a Compressor

9. 2. Capillary tube Capillary tube is used to keep communication
between compressor and condenser.

10. 3. Condenser
It is  a device or unit used to condense vapor into liquid. It radiate heats in the air.
It is attached at the back side of the refrigerator.

11. 4. Evaporator
It is a inner part of refrigerator. It remains close to the foods and meats.
When the compressed Freon gas pass into it takes heat from foods and give
the heat to the Freon gas.

12. Temperature sensor
This sensor is used to maintain the thermo system of a
refrigeration . When the foods and drinks are cold enough, it
stops the compressor. By doing this it saves energy and money.

13. 6. Ice maker Ice pot Ice maker make water to ice and in the
ice pot ice are stored. They are situated
In the deep part.

14. 7. Treys and pots

15. 8. Monitor of Modern
Refrigerators

16. 9. Doors of refrigerators

17. 10. Deep part of refrigerator.

18. 11. Lower or normal part of refrigerator

19. Mechanism and process of refrigerators.
The main task of a refrigerator is to take out the heat from the
inner part of it. For this process refrigerator use a gas name Freon
for heat transfer medium. There is some mechanism and process
for this process which is invented after a lot of experiment.
So lets see how it works

20. Compressor
Compressor is a device that create pressure on gas and decrease
the volume of gas. There is a piston inside of it. The piston helps to create
the Pressure on the gas. Actually it has a great importance to do the refrigeration Circle. It is like the heart of refrigerators. There is a variety in compressor as their capacity. It decrease the volume of Freon gas by
Creating pressure and turn the Freon gas into liquid . When this liquid
Freon gas runs into the evaporator, takes the heat from foods and the gas increase its volume for the heat and low pressure. Then the compressor
Creates some empty space so that the Freon gas can come again into the compressor. Thus it keeps the circle on.

22. Evaporator
It is a inner part of refrigerator. It remains close to the foods and meats.
When the compressed Freon gas pass into it takes heat from foods and give the heat to the Freon gas. It is actually heat transfer medium between the inner part and the Freon gas.
Condenser
Condenser transfer heat from Freon gas to the atmosphere. Being
Attached at the back side of refrigerator when the warm vapor of
Freon gas pass through it, it takes the heat and the volume gas
increases. Then the gas goes to compressor again.

24. Now lets enjoy a video clips about the refrigeration process
Up to now we discussed about mechanism and process of refrigerators with
diagram .
Now lets enjoy a video clips about the refrigeration process
of a refrigerator

26. The worlds best brand for modern refrigerators
Whirlpool

27. Kenmore brand’s refrigerators

28. Asko brand’s refrigerator

29. LG brands refrigerators

30. Samsung brands refrigerators

31. In Bangladesh walton is the best brand for refrigerators.

32. My one refrigerators
Bangladeshi product

33. Prizes of Refrigerators of different brands
Whirlpool – starts 50,000tk to 1,5000tk and more
Kenmore – starts 45,000tk to 1,3000tk and more
Asko – starts 42,000tk to 1,2000tk and more
LG – starts 37,000tk to 1,0000tk and more
Samsung – starts 35,000tk to 80,000tk and more
Walton – starts 28,000tk to 50,000tk and more
My one – starts 23,000tk to 45,000tk and more

34. Thank You