Explanation of Refrigeration Principle of Condenser

Date:Mar 18, 2020

To talk about the principle of condenser, first understand the concept of condenser, in the process of distillation, the device that converts vapor into liquid is called condenser.

For the refrigeration principle of most condensers, the function of the refrigeration compressor is to compress the steam with lower pressure into the steam with higher pressure, thus reducing the volume of the steam and increasing the pressure.  The refrigeration compressor sucks the working medium vapor with lower pressure from the evaporator, raises the pressure and sends it to the condenser, where it condenses into the liquid with higher pressure. After throttling by the throttle valve, it becomes the liquid with lower pressure and then sends it to the evaporator, where it absorbs heat and evaporates into the vapor with lower pressure, thus completing the refrigeration cycle.

First, the basic principle of refrigeration system

After the liquid refrigerant absorbs the heat of the cooled object in the evaporator, it vaporizes into low-temperature and low-pressure steam, is sucked by the refrigeration compressor and compressed into high-pressure and high-temperature steam, which is then discharged into the condenser, where it releases heat to the cooling medium (water or air), condenses into high-pressure liquid, is throttled into low-pressure and low-temperature refrigerant by the throttle valve, and enters the evaporator again to absorb heat and vaporize, thus achieving the purpose of circulating refrigeration.  In this way, the refrigerant completes a refrigeration cycle through four basic processes of evaporation, compression, condensation and throttling in the system.

In the refrigeration system, evaporator, condenser, compressor and throttle valve are the four essential parts of the refrigeration system, of which evaporator is the equipment for conveying cold energy.  The refrigerant absorbs the heat of the cooled object to realize refrigeration.  The compressor is the heart and plays a role in sucking, compressing and transporting refrigerant vapor.  Condenser is a device that emits heat. It transfers the heat absorbed in evaporator to cooling medium together with the heat converted by compressor work.  The throttle valve throttles and depresses the refrigerant, controls and regulates the amount of refrigerant liquid flowing into the evaporator, and divides the system into two parts: the high-pressure side and the low-pressure side.  In actual refrigeration systems, in addition to the above four components, there are often some auxiliary equipment, such as solenoid valves, distributors, dryers, collectors, fusible plugs, pressure controllers and other components, which are set up to improve the economy, reliability and safety of operation.

Second, the principle of vapor compression refrigeration

A single-stage vapor compression refrigeration system is composed of four basic components: a refrigeration compressor, a condenser, an evaporator and a throttle valve.  They are connected in turn by pipelines to form a closed system. Refrigerant continuously circulates in the system and changes state to exchange heat with the outside.

III. Composition of Main Components of Refrigeration System

Refrigeration units can be divided into water-cooled refrigeration units and air-cooled refrigeration units according to condensation forms, and can be divided into single-cooling units and refrigeration and heating units according to use purposes. No matter which type is composed, it is composed of the following main components.

The main components of the refrigeration system include refrigeration compressor, condenser, evaporator, expansion valve (or capillary tube, supercooling control valve), four-way valve, compound valve, one-way valve, electromagnetic valve, pressure switch, melting plug, output pressure regulating valve, pressure controller, liquid storage tank, heat exchanger, heat collector, filter, dryer, automatic switch, stop valve, liquid injection plug and other components.

The main components of the electrical system include motors (for compressors, fans, etc.), operating switches, electromagnetic contactors, interlock relays, overcurrent relays, thermal overcurrent relays, temperature regulators, humidity regulators, and temperature switches (for defrosting and preventing freezing, etc.).  Refrigeration compressor crankcase heater, water cut-off relay, computer board and other components.

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