Heat exchangers are a type of equipment used mainly to transfer heat from one medium to another efficiently. They are the basic technology behind many household items, including heating systems, refrigerators and air conditioners. There are many different types of heat exchangers, each of which serving different purposes for different applications. Although the advantages of heat exchangers are apparent in the immense variety of applications they have, heat exchanges also have some disadvantages.
Many modern heat exchangers, such as the plate heat exchanger, are very adaptable, which makes them suited for a wide variety of tasks. Heat exchangers have also become compact, which makes them useful in smaller and smaller items. Although early heat exchangers were often as large as a refrigerator, heat exchangers as of 2011 can even be used for small portable heaters or room air conditioners. Heat exchangers are also quite flexible, because the fluid used to mediate the heat exchange can be modified to design specifications.
Cost and Maintenance
The fabrication costs of heat exchangers have fallen as technology has progressed. Modern plate heat exchangers use pressed plates, which are less expensive than the welded plates used on early models. Pressed plates are also more resistant to corrosion and chemical reactions that would weaken the heat exchanger and require more frequent replacement. Many heat exchanges have even been modified with ease of cleaning in mind. For example, with plate heat exchangers, you can easily remove and replace plates individually rather than needing to take apart the whole system.
The heat exchanger as a piece of equipment is a simple model and therefore, has many applications in industry. The coolant in radiator coils in an internal combustion engine is one example of a heat exchanger. In addition, heat exchangers are also used in chemical plants, petroleum refineries, sewage treatment and nuclear power facilities.
Leakage and Pressure
Leakage and pressure drops in the system are two possible disadvantages of heat exchangers. Leakage in the process of heat transfer is difficult to prevent and repair. In fact, many heat exchangers need to be taken apart entirely in order to fix a leak. Similarly, a drop in pressure across a plate heat exchanger requires checking every plate for the fault.