Another name of the vaporizer used in the cooling system is evaporator. It is also called cooling coil for vaporizer. The vaporizer is the part where the coolant enters as liquid, evaporates and arises as gas in the cooling systems. The coolant enters into the channels of the evaporator, absorbs the heat from the cooled substance or the environment and starts to boil and evaporates while absorbing the heat from the environment. As a result of the processes, the evaporator carries out the cooling which is the general purpose of the whole system.
What are the evaporator types?
Various evaporator types have been developed to meet the user’s needs. The most used ones are evaporators with blower, with serpentine (with fan) or with forced convection. The plumbing system with no joint is placed between two metal plates which are welded with each other from their edges. The cooling carries out by creating vacuum in the gap left between the plates. These plates are grouped and used by mounting in shelves creating a serial flow pattern for the cooler.
What are the areas of use of evaporators?
Evaporators with plates are commonly used for the needs such as small refrigerators used in the places where mass production happens, freezers and soda sources. Evaporators with plates are also used for establishing storage areas with low temperature by mounting in groups or piles. The coolant pipes used for this type may be mounted in series or in a parallel way, depending on the usage needs. As well as, evaporators with plates may be used in the lorries and ship’s stores with cool storage, it may be also used for storing the cooled and frozen food products. Serpentine with bare pipe are small evaporators using copper pipes. Serpentine with bare pipe may be used for the need of cooling the air or any liquid. Steel pipe is used in the evaporators in the systems using ammoniac as cooler or in big evaporates having coolers in other types. A thin air layer behaves like insulator and first decelerates the process of heat transmission depending on the surface area and temperature difference and then stick on the surface of a serpentine. One of the methods to overcome or balance the transmission loss caused by the thin air layer is to increase the surface area. A winglet is added to the evaporator pipes for this. Adding winglets does not eliminate the air layer, even, it increases the adhesive area, however, it provides more surface area without increasing the size of the serpentine during the heat transmission. Another way of preventing the heat transmission loss caused by the air film is to add a fan or blower ensuring the air to move fast along the evaporator. The evaporator of this type is the evaporator with forced cooling. Depending on the design and the use of the serpentine, the fan moves along the air serpentine with either the induction or forced circulation of the air. Using a fan increases the air flow and the heat transmission from the air to the cooler in the serpentine. Because a large quantity of air will get in touch with the surface area of the air serpentine. Many serpentine manufacturer have designed the heat transmission units in the form of obfuscatory pipe lines. Therefore, with the use of the blower, more air volume will get in touch with either pipe surface or the winglets in connection with it. As a result of the forced or inducted air movement in the serpentine, it will leave more air heat in the cooler in the serpentine in a certain time. The serpentines with liquid cooling, just like the serpentines with air cooling, are designed in various forms depending on their use and the field of application. Because there is a bigger heat transmission between liquids and metals than that of between air and metals, an underwater serpentine has capacity to absorb many times more heat than the serpentine with air cooling under the similar conditions.