What Is a Cooling Coil?
A cooling coil is a component used in a heat exchanger. It consists of piping formed into a spiral shape, although other shapes are also available and designed based on specific equipment and purposes.
Water is primarily used as the refrigerant in cooling coils. Since the refrigerant flowing through the cooling coil gets heated due to heat exchange, it’s essential to lower its temperature. For this purpose, cooling coils are often used in conjunction with chillers.
Uses of Cooling Coils
Cooling coils are employed to regulate the water temperature in water tanks and help lower the tank temperature during temperature spikes, such as in the summer.
They are also utilized to control the temperature of liquids used as raw materials in various factory equipment. Cooling coils are directly immersed in the liquid to be cooled, making them highly efficient for cooling and ensuring stable temperature control. Maintaining a constant temperature of raw materials is crucial to prevent changes or increased reactivity, resulting in inconsistent products. Cooling coils play a pivotal role in temperature control to avoid such issues.
Principle of Cooling Coils
Efficiently removing heat from a hot object and cooling it down involves several key factors. First, a liquid with high heat capacity and low temperature should flow as rapidly as possible. Additionally, the surface area of the piping through which the refrigerant flows should be increased. Agitation is also effective when dealing with hot liquids or gases. Cooling coils have intricate shapes, such as spirals, to enhance the surface area of the piping and improve cooling efficiency.
Piping for cooling water is often made of copper, which is an excellent material with high thermal conductivity. It is cost-effective and easy to process. However, copper is susceptible to corrosion and heat. Therefore, when cooling targets involve liquids or gases that can corrode copper or are at high temperatures, more durable materials like stainless steel are used.
The amount of heat removed from the object being cooled can be easily calculated based on the volume of water flow and the measured temperature increase. For example, if the temperature of the cooling water rises by 1°C when 1 liter of cooling water flows per minute, it removes 1 kcal of heat per minute.
While water is commonly used as a refrigerant, hydrogen is sometimes employed as a gaseous refrigerant due to its high heat capacity and cooling effect.