Boilers and heat exchange manufacturing is a big business in the United States. The 2013 revenue for this manufacturing was about $7 billion, and projections put that market at over $19 billion by 2021. If you’re curious what exactly a heat exchanger is, the difference between a shell and tube heat exchanger and other types of heat exchange design, and why they need to be kept in good repair, read on.

What is a Heat Exchanger?

As the name suggests, a heat exchanger transfers heat from one thing to another, often from one fluid to another. They are used most obviously in heaters, but also in refrigerators and air conditioners. Some types of heat exchangers include the shell and tube heat exchanger, the parallel flow configuration, and the cross flow configuration.

How Does a Shell and Tube Heat Exchanger Work?

This style is made up of tubes divided into two sets. One set has the liquid that needs to be heated or cooled, and the other has the liquid that will either trigger heat exchange or whisk heat away from the first set. It is very important that the wall of the tubes be just the right material and diameter.

Why is the Design of Heat Transfer Coils so Important?

The two fluids have to be at different temperatures and come into thermal contact for the right type of thermal management. Convection happens in each fluid and conduction through the wall that separates them. The material of the tubes must facilitate this heat transfer perfectly.

Fluid Passes

Heaters can be classed according to how many times the fluids pass over one another. If it happens only once, this is a single pass heat exchangers. The other option is a multi pass heat exchanger

Flow Direction

When a heater is referred to as parallel flow, this means the tube side fluid and the shell side are flowing in the same direction. in this type of shell and tube heat exchanger, the fluids enter from the same end and must have a large temperature difference. A cross flow exchanger has fluid flowing through only one tube, so the second fluid passes around the tubes.

Heat exchangers are one of the most important of part of industrial equipment, both for heating and cooling. It is essential to keep heat exchangers properly maintained and serviced so they will keep to optimum performance levels.