REFRIGERATION

REFRIGERATION

1. The Foundation of the unitary cooling operation

   • When two bodies at different temperatures are in contact, the body with the highest content of heat yields energy cooling down as a consequence

2. Thermodynamic properties

   • Pressure
     • You must operate with positive pressure
   • Temperature
     • You must have a critical temperature above the condensing temperature
   • Volume
     • Must have a value under specific volume in vapor phase, and a high value of volume in the liquid phase
   • Enthalpy
     • You must have a high value of latent heat of vaporization
   • Density
   • Entropy

3. Industrial Coolants

   • Ammonia
     • The boiling point of the ammonia under standard atmospheric pressure is -2,22 °C, the pressure in the evaporator and the condenser in the conditions of tonne standard is -15 °C and 30 °C are 34.27 pounds per inch2 and 169.2 pounds per inch2 abs.
   • Refrigerant 22
     • storage chambers and facilities for food processing: refrigeration and air conditioning on board different transport; heat pumps to heat air and water. Has a boiling point at atmospheric pressure of 40.8 °C. The temperatures on the evaporator are as low as 87 °C.
   • Refrigerant 134-a
     • low toxicity, has shown that it is fuel to pressures as low as 5.5 psig to 177 °C when mixed with air at concentrations usually greater than 60% by volume in air
   • Refrigerant 401a
     • Some applications of this coolant are domestic refrigerators, freezers, cooling equipment for food of average temperature of humidifiers, ice machines and vending machines for drinks. Operating with a evaporation temperature of -23 °C (-10 °F) and above.
   • Direct hydrocarbons
     • All are extremely flammable and explosive. Its use is normally limited to special applications where you need the services of specialized personnel.

4. component of refrigeration

5. Behavior of the refrigeration cycle

   • • The basic cycle of cooling operates as follows: the high-pressure liquid refrigerant is fed into the tank hall through the liquid line, passing by a desiccant filter to the instrument of control, which separates the high side and low pressure of the system. In accordance with the low-temperature coolant passes through the evaporator, the heat of the element to cool flow through the pipes of the same into the coolant, causing the action continue boiling until the coolant is completely vaporized.

6. Matter balance

7. Tons of refrigeration

   • It is the nominal power unit used to refer to the ability to pull heat load (cooling) of the refrigerating equipment and air conditioning

8. Net effect of cooling

   • The clear refrigeration effect is equal to the useful refrigeration, that is to say, the heat extracted in fact from the space that is equipped.

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