A heat exchanger is a device that is used to exchange or transfer heat from one fluid form to another. Heat exchangers are used in heaters and in cooling applications like air conditioning units and refrigerators.
Heat exchangers are classified based on the direction of the liquid flow. Exchangers can be cross-flow, counter current, or parallel-flow. In a parallel-flow heat exchanger, fluids move in one direction, and enter and exit the system side by side. The fluid paths in cross-flow heat exchangers, on the other hand, run perpendicular to one another. In countercurrent heat exchangers, fluids flow in opposite directions and are known to be more effective than other exchangers.
Apart from identifying heat exchangers based on the direction the fluid flows, systems are also identified by their composition. There are heat exchangers that are comprised of various tubes, while there are systems that use hot plates with spaces in between for the flowing liquid.
If you are planning to use heat exchangers on your property, identifying the different types of systems on the market can help you decide what to invest in. You can go online to gather information from websites such as mahans.com before you start buying anything.
A plate heat exchanger has thin plates that are joined together, with a small space in between them. The plates are kept in place by a rubber gasket. It has a large surface area, and the corners of each plate have a small opening that allows fluid to flow, extracting heat in the process.
The fluid channels are alternately hot and cold, allowing the heat exchanger to cool and heat fluids. This type of exchanger is mostly used in refrigeration applications, and because of its larger surface area, these are considered more effective than other types of heat exchangers.
Shell and Tube Heat Exchangers
A shell and tube heat exchanger is made out of various tubes where liquid flows through. There are two sets of tubes inside the exchanger. The first set of tubes contains the liquid that has to be cooled or heated, while the second set of tubes contains the liquid that is used to activate the heat exchange process.
The liquid in the second set of tubes cools the liquid in the first set of tubes by absorbing heat and transferring it away. It also warms the liquid by transmitting its own heat to the other set of tubes. Shell and tube heat exchangers are among the most challenging to design.
Extreme care must be taken to determine the right thickness of the tubes’ walls. The tubes also need to have specific diameters to get the best results. This type of heat exchanger can be designed to assume any of the three liquid flow patterns discussed earlier.
Adiabatic Wheel Heat Exchangers
In an adiabatic wheel heat exchanger, intermediate fluids are used as heat storage, which is then transferred to the other side of the heat exchanger. The adiabatic wheel is a large wheel that has threads that rotate both hot and cold fluids to transfer or extract heat.
Regenerative Heat Exchangers
In regenerative heat exchangers, one type of fluid is passed from one side of the exchanger to another side. This can either be a shell and tube heat exchanger, or a plate heat exchanger. The heating fluid can get very hot in this type of exchanger, so the exiting fluid is used to warm up the cooler, incoming fluid. This allows the exchanger to maintain a constant temperature while being used.
Regenerative heat exchangers are the most energy efficient because of their cyclical process. All relative heat is transferred from the hot exiting fluid to the much cooler, incoming fluid. This exchanger is able to maintain a constant temperature using only a little energy to raise and lower overall heat.
Why Use Heat Exchangers?
Heat exchangers are very adaptable, which makes them perfect for a wide range of tasks. They can be used to heat or cool areas and, with their compact designs, heat exchangers can be used in smaller applications.
Maintaining Heat Exchangers
Plate heat exchangers are very cost-effective and are designed to have a strong resistance to chemical reactions and corrosion. This means that your heat exchanger can last for a long time, and it requires less frequent replacement.
Heat exchangers are the power behind many household and commercial items. Choosing the right heat exchanger can serve specific purposes for specific applications. Take the time to understand your specific needs to determine the right type of heat exchanger for you. Gather information from local HVAC contractors and suppliers, or go online to check out sites like mahans.com to find the heat exchanger best suited to your needs.