Heat is transferred by conduction through the exchanger materials which separate the mediums being used. A shell and tube heat exchanger passes fluids through and over tubes, whereas an air-cooled heat exchanger passes cool air through a core of fins to cool a liquid.
There are various types of heat exchangers-
- Shell and tube heat exchanger
- Plate heat exchangers
- Plate and shell heat exchanger
- Adiabatic wheel heat exchanger
- Plate fin heat exchanger
- Pillow plate heat exchanger
- Fluid heat exchangers
- Waste heat recovery unitsDynamic scraped surface heat exchanger
- Phase-change heat exchangers
- Direct contact heat exchangers
- Micro-channel heat exchangers
Heat exchangers are commonly used for cooling of hot gasses and liquids, especially in industrial and manufacturing processes. They can also be used to generate heat; for example, an Exhaust Gas Heat Exchanger can use the heat from exhaust gasses to heat up a water circuit, which can then be used around a building.