One of the most beneficial advancements in the engineering departments is the making of the Heat Exchanger. In essence, it is that piece of equipment or machinery that is designed to build an efficient means of heat transfer. This transfer of heat is done primarily from one medium to another. The media that lies in between and is interrelated may be having a solid wall separating it, which allows them to never mix with each other. Having said that, there are instances where the media is in complete direct contact.
one of the most wide and well accepted usage of the Heat Exchanger is in the fields such as refrigeration, power plants, air conditioning, space heating, petrochemical plants, chemical plants, petroleum oil refineries, processing of the natural gas as well as the sewage systems and their treatments. The internal combustion engines are one of the most basic as well as the most classic examples of Heat Exchanger concept. The internal combustion engines circulate a coolant that is known as the engine coolant. This coolant flows all through the radiator coils and the air flows all around and past these coils. This process cools down the coolant and also heats the air that is incoming.
According to the flow arrangement that they have, there are basically two classifications of the Heat Exchanger. These are the parallel flow and the counter flow. Parallel flow Heat Exchanger has two types of fluids enter the exchangers at the same ends. These fluids travel parallel to each other and reach the other sides. While on the other hand, in the counter flow Heat Exchanger, the fluids go in opposite directions, meaning that they enter the exchanger from opposite sides. To this date, we have seen that the counter flow designing has been most widely used for being so efficient. This is so because it can transfer the maximum amount of heat from the heat transferring mediums.
It should be also noted that there is another type of Heat Exchanger, which is known as cross flow. The cross flow Heat Exchanger has the fluids travelling in roughly perpendicular positions to each other throughout the exchanger.
The designing of Heat Exchangers is usually as such to help the efficiency of the process. That is why the design has maximum surface area of wall area between the fluids. There is also minimization of the fluid flow all over the exchanger to make the process fluent. Fins and corrugations can drastically affect the performance of the exchangers, if these are in one or both of the directions. This addition of the fins and corrugations also increases the surface area and may even channel the fluid flow. In some instances, it may even induce some turbulence.
All across the surface of heat transfer, the driving temperature does vary with the positioning. Having said this, it is easy to define an appropriate mean temperature. The simple systems of Heat Exchanger use the LMTD –Log Mean Temperature Difference. At some instances, you may even see the usage of NTU methods.
SONDEX South East Asia Pte Ltd is part of the much known SONDEX global group. With the headquarter located in Denmark, SONDEX has been providing state of the art facilities for Plate Heat Exchangers and Fresh Water Distillers since 1984.