Some Terminology Of Refrigeration(I)

- Sep 26, 2019-


Refrigeration: The process of removing heat from an object or fluid and releasing heat into an environmental medium to produce a lower temperature than the ambient temperature. 2, refrigerant: in the refrigeration device to continuously complete the cycle of the working material.

Refrigerants: ammonia, freon (R22, R134A, R407C, R410A), water. 3, load-load agent: is used in indirect refrigeration system to transmit the cold medium intermediate medium.

Commonly used refrigerants:Refrigerants R22,R134a,R404a,R407C,R410a,R507,R32,R125,R23,R1234yf,etc.

Refrigeration capacity: Heat transferred per unit of time from a chiller (air conditioner) from a low-temperature object to a high-temperature object.

Heat production: Heat delivered to the room by the air conditioner (heat pump type) after absorbing heat from the outside world in a unit of time. COP - Refrigeration/Compressor electrical power.

The winter heat pump cycle performance factor and the energy efficiency ratio expression of the summer heat pump are expressed in cop (energy efficiency ratio). EER - Total electrical power of the refrigeration/air conditioning system (the higher the EER value means that evaporation absorbs more heat in the air conditioner or the compressor consumes less electricity).

When refrigeration in summer, the ratio of cooling capacity (W or Btu/h) to input power (W) is defined as the energy efficiency ratio of the heat pump to eER.

Standard units:  

watts (W) or kilowatts (KW)

1KW s 860kcal/h

1 U.S. Cold Ton s 3.526kw s 3024kcal/h (Note: 1 cold ton is the amount of cooling required to make 1 ton of water 0 C into 0 oC of ice in 24 small houses.)

Heat: The temperature of a substance rises or drops during heat absorption or heat release, but the shape of the substance does not change, and this heat is called heat absorption.

Subvention: The shape of the substance in the process of absorbing or releasing heat, but the temperature does not change, this heat can not be measured by a thermometer, the human body can not feel, but can be calculated by experiment, this kind of heat is called latent heat.   

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Dry ball temperature: (symbol DB) normal temperature.

Wet bulb temperature: (symbol WB) the temperature of the thermometer when wet, affected by humidity.

Dew point temperature: (symbol DP) to cool the air, the air moisture began to dew the temperature.

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Wetness: The amount of water vapor in the air. Absolute humidity: The quality of water vapor in 1m3 wet air.(units: kg/ water/kg/ dry air) 

Relative humidity: The ratio of absolute humidity of wet air to absolute humidity of saturated wet air at the same temperature.

(unit, symbol RH) 

Saturated wet air: The amount of water vapor in the air is limited, and the wet air when the maximum capacity is reached is called saturated wet air.

Pressure is the force per unit area, expressed in P.

Its unit is Pascal, referred to as Pa.;( KPa.

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Absolute pressure: The pressure that acts directly on the surface of a container or object.

The "absolute pressure" value starts with an absolute vacuum. Table pressure: The pressure measured by the pressure gauge is the table pressure.

"Table pressure" starts with atmospheric pressure.

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A standard atmospheric pressure: 0.1013MPa, 1.03 kg/cm2, 760 mm Hg, 10.3 m water column