Refrigerator and Reverse Carnot Cycle

Reverse Carnot Cycle 

       

Why Reverse Carnot cycle is an Ideal Cycle...?

      We know that every refrigerator work on the reverse Carnot cycle. as Carnot cycle consist adiabatic portion and isothermal portion one after another. In actual conduction required adiabatic portion speed of piston is high, and isothermal portion speed of piston s slow, which is impossible in actual condition That's why Reverse Carnot cycle is an ideal Cycle. 

Watch the video for more detail information

What are the processes in Carnot cycle...?

            It consist two reversible isothermal processes and two reversible adiabatic processes

As given

Process 1-2 :-Reversable isothermal heat absorption from low temperature...

Process 2-3 :- Reversible adiabatic compression

Process 3-4 :- Reversible isothermal heat rejection at high temperature

Process 4-1 :- Reversible adiabatic expansion

                    It means that heat absorption and heat rejection take place at constant temperature. Also compression and expansion take place at constant pressure.

Watch video for Derivation of Reverse Carnot cycle Formulas

Bell Coleman Air Refrigeration Cycle

About Bell Coleman Air Refrigeration Cycle

          The Earliest type of refrigerator works on the bell Coleman cycle with air as working substance. The isothermal process from Carnot cycle are replaced by constant pressure process. The schematic diagram of Bell Coleman cycle Can be as...

Schematic representation of bell-coleman cycle

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      Bell Coleman cycle consists of compressor, expander, heat exchanger, and evaporator. The air from evaporator is drawn into compressor and is compared to heat exchanger pressure isentropically. During compression along with presser rise, temperature of air also increase. This warm compressed air is forced into heat exchanger, which cool the air at constant pressure. It has an effect of reducing volume from 3 to 5. Simultaneously it's temperature also reduces due to rejection of heat . This low temperature air is drawn into expander, Where it is expanded isentropically. This isentropic expansion reduce the temperature of air bellow that of evaporator temperature. This air at least temperature is passed to evaporator, where it absorb heat at constant pressure and produce refrigeration effect. 

Refrigerants types and properties

What is Refrigerant??

          A Refrigerant is defined as any substance that absorb heat through expansion or vaporization & loses .It through condensation in a refrigeration system the term refrigerant broadest sense is also applied to such secondary cooling medium as a cold water or brine solution. Usually refrigerant include only those working medium which pass through the cycle of evaporation, recovery, compression, condensation & liquidification. This substance absorb it at one place at low temperature level &reject the same at some other place having higher temperature & pressure all the refrigerant change from liquid state to vapour state during the process .

 Classification of Refrigerants:- 

 The refrigerants are classified as follows:

 1. Primary refrigerants.

 2. Secondary refrigerants.

1. Primary refrigerants.

           Primary refrigerants are those working mediums or heat carriers which directly take part in the refrigeration system and cool the substance by the absorption of latent heat 

eg.. Ammonia, Carbon dioxide, Sulphur dioxide, Methyl chloride, Methylene chloride, Ethyl chloride and Freon group etc. 

2. Secondary refrigerants. 

          Secondary refrigerants are those circulating substances which are first cooled with the help of the primary refrigerants and are then employed for cooling purposes, 

e.g., ice, solid carbon dioxide etc.

        

Trends in Domestic Refrigeration

Do you want to know about Trends in Domestic Refrigeration???

             the people with normal health and peculiar habit prefer to take tasteful diet in order to satisfy the tongue in addition to fulfill the requirement for normal functioning of the boy organ. But , our habit for particular commodities calls for conservation of perishable commodities even during those period during which they are not naturally available. Hence the people need to be crated an artificial environment in which minimum spoilage will occur.

          This article describes the trends of R&D in commercial refrigeration from history to now a days, with particular reference from Books, Internet, news article and guided by teachers.

             The development occured in refrigeration field in order to enhance the energy, reduce the environmental pollution and increase the performance of equipment and components used in refrigeration. In particular, a case study is discussed concerning with the step by step progress in refrigeration system.

            Refrigeration is defined as the branch of science that deals with the process of reducing and maintaining the temperature of a space or material, below the temperature of the surrounding.

             The space, which is maintained at lower temperature is known as refrigerated space while the machine, that maintain the space at a lower temperature than the surrounding is known as refrigerator and the process is called as refrigeration.

            A refrigerator consists of a thermally insulated compartment and a heat pump that transfers heat from the inside of the fridge to its external environment so that the inside of the fridge is cooled to a temperature below the room temperature. Refrigeration is an essential food storage technique in developed countries. The lower temperature reduces the reproduction rate of spoilage. 

           Freezer units are used in households and in industry and. Domestic refrigerators and freezers for food storage are made in a limited range of sizes. Refrigerators and freezers may be free standing or built into a kitchen. The refrigerator allows the modern household to keep food fresh for longer than before. Freezers allow people to buy food in bulk and eat it at leisure, and bulk purchases save money.

      #The main components used in refrigeration system are as follows:- 

#Compressor

#Condenser

#Expansion valve 

#Evaporator

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