We all know that an industrial refrigeration system produces cold, which is used to freeze food, air-conditioning living spaces, cool drinks, etc. However, not all of us understand that this cooling depends on a hot spot, which needs a heat sink to transfer energy to the environment. This apparent contradiction has its explanation within the laws of thermodynamics, on which the principle of operation of these systems is based.

What is a heat sink?

A heat sink is a piece of equipment designed to transfer heat from a given point or site to the environment. Therefore, according to the laws of thermodynamics, said the site must have a higher temperature than the environment. In this way, it is possible to lower the temperature of the point in question, thanks to the transfer or exchange of heat towards the environment. For this reason, the heat sink is also known as a heat exchanger or thermal energy.

In an industrial refrigeration system, the aforementioned hot spot is represented by the refrigerant gas that comes out of the compressor at a high temperature. This gas needs to be cooled by a heat sink, which will transfer much of the thermal energy from the gas to the environment.

Heat sink: what types are there?

Considering the physical medium used to lower the temperature, the heat sink can be powered by air or water. Next, we will detail each type of heat sink:

Air heat exchanger

Air cooling is widely used in refrigeration systems. This cooling can be static or passive, taking advantage of the natural contact with fresh air. However, when fans are used, forced-air cooling is more effective than static.

In refrigeration systems, the hot gas that leaves the compressor passes through the interior of the copper tubes of a coil. Consequently, the heat from the gas is transferred to the metal walls of the coil tubes. Then, this heat passes into the air through natural contact or by forcing it with a fan. Finally, at the exit of the coil, the refrigerant comes out in a liquid state, ready to pass to the other part of the refrigeration circuit.

Water heat sink

This heat sink is more effective than air cooling since water can absorb more heat energy than air. For this reason, the water sink is used in all heavy-duty industrial and commercial refrigeration systems.

A water sink is made up of a hermetic tubular steel structure, through which cold water circulates. Inside the structure, submerged in the water, a coil of copper tubes conducts the hot refrigerant to be cooled. In this way, heat exchange is carried out to lower the temperature of the refrigerant gas leaving the compressor. Cold water entering the structure absorbs heat and leaves hot to a cooling tower.

A plate heat sink or exchanger is also another water cooling equipment. However, it has a different structure than the heatsink mentioned above. A plate heat exchanger is made up of many thin-gauge metal plates, which are stacked against each other in a bolted structure. The plates provide a tight path for water and another path for hot refrigerant gas. In this way, heat transfer is done through the metal walls of the plates.

If the thermodynamic efficiency of the mentioned heatsinks is compared, the plate heat exchanger has the highest efficiency. However, the tubular heatsink has a much more robust constitution, which makes it the most suitable for working with high pressures.

Importance of heat dissipation in an industrial refrigeration system

In refrigeration systems, the heat sink is known as a condenser. This name is due to the fact that, at the outlet of the heatsink, the refrigerant must come out in a liquid state. If the refrigerant does not come out in a liquid state at the condenser outlet, then the system will lose its ability to generate cold. Therefore, it is essential that the condenser dissipates as much heat as possible, to ensure the phase change of the refrigerant from gas to liquid.

When using an air condenser, attention must always be paid to the correct operation of the fan. In addition, the coil must also be cleaned periodically, so that its ability to exchange heat with the environment does not decrease. On the other hand, a water-cooled condenser needs preventive maintenance to remove deposits and scale that water leaves internally. These deposits hinder heat transfer between the coil and the water.

Intersam, a company specialized in the manufacture of capacitors

If you suspect that your condenser has heat dissipation failures, it is important that you contact a specialized company. At Intersam we put at your disposal all our experience in the design and manufacture of commercial and industrial condensers. Therefore, contact us so that we can give you an effective solution that meets the needs of your refrigeration system.