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Heat exchanger

technology Maturity 11-13 Next article →

A heat exchanger is a special system used to move heat.

Shell and tube heat exchanger
Shell and tube heat exchanger

It moves heat between a source and a working fluid. This can be used to heat things up or cool them down. These tools are used in many different places. You can find them in power stations and chemical plants. They are also used in air conditioning and refrigeration.

Delta T 1
Delta T 1

Even the engine in a car uses one to cool its fluid. This is called a radiator.

There are three main ways the fluids move through the system. In parallel-flow, both fluids enter at the same end. They travel together in the same direction to the other side. In counter-flow, the fluids enter from opposite ends.

Comparison of con- and counter-current flow exchange
Comparison of con- and counter-current flow exchange

This counter-flow design is the most efficient way. It works well because the temperature difference stays higher. The third way is cross-flow. In this way, the fluids travel roughly perpendicular to each other.

Engineers use different designs based on how much heat they need to move. Double-pipe heat exchangers are the simplest kind. They are cheap to design and easy to maintain. Because of this, small industries often use them. Large industries usually prefer more efficient types like plate or shell-and-tube models.

Plate frame 2
Plate frame 2

Some machines work at low temperatures up to 650°C. Others are high-temperature models. These can work at 1000°C or even 1400°C.

A shell-and-tube heat exchanger is a very strong design.

Shell and tube heat exchanger
Shell and tube heat exchanger

One fluid flows through a bundle of tubes. A second fluid flows outside those tubes but inside a large shell. Baffles are used inside the shell to help. They support the tubes and direct the fluid flow. Baffles also create turbulence to help move heat better. These exchangers are great for high-pressure jobs. They can handle pressures greater than 30 bar.

Straight-tube heat exchanger 1-pass
Straight-tube heat exchanger 1-pass

Some heat exchangers can even change the state of a fluid. A condenser is a tool that cools hot gas. It turns that gas into a liquid through condensation.

Surface Condenser
Surface Condenser

On the other hand, a boiler can create steam. This process is called vaporization. Plate heat exchangers also use thin metal plates to work. They use gaskets to keep the fluids from mixing. These plates often have patterns to increase the surface area.

Plate frame 1
Plate frame 1

This helps the heat move even faster.

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🖼️ Images & Media (15)
File:Tubular heat exchanger.png
Tubular heat exchanger.png
File:Shell and Tube Heat Exchanger of Chiller.jpg
Shell and Tube Heat Exchanger of Chiller.jpg
File:Delta T 1.svg
Delta T 1.svg
File:Straight-tube heat exchanger 1-pass.svg
Straight-tube heat exchanger 1-pass.svg
File:Shell_and_tube_heat_exchanger.jpg
Shell_and_tube_heat_exchanger.jpg
File:Plate frame 1.svg
Plate frame 1.svg
File:Plate frame 2.png
Plate frame 2.png
File:PHE Trieste 013.jpg
PHE Trieste 013.jpg
File:Kettle reboiler.svg
Kettle reboiler.svg
File:Surface Condenser.svg
Surface Condenser.svg
File:HCHE.jpg
HCHE.jpg
File:Spiral-heat-exchanger-schematic-workaround.svg
Spiral-heat-exchanger-schematic-workaround.svg

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