Heat exchangers have been around for over one hundred years. In fact, the first known method of such a process is thought to be during ancient times, when rocks where put into a fire to absorb the heat of the flames. After heating up, the rocks could then be removed and used to heat something else, such as a bucket of water. Here are a few ways in which the technique works in today’s industries.
What Exactly Is a Heat Exchanger?
A heat exchanger allows for two fluids, or one fluid and one solid surface, or between solid particulates and one fluid, to exchange heat without coming into contact with each other. The advantage to this method is a significant increase in efficiency. Heat exchangers are used in a wide variety of machines, from automobiles to furnaces. However, the appropriate heat exchanger for a home water heater is not appropriate for waste heat recovery.
The heat transfer between the fluid to be heated and the other substance occurs in a chamber within a larger machine or device. For example, a company such as Elanco makes dozens of different types of heat exchangers. Each heat exchanger by Elanco would serve a different device or machine. For example the heat exchanger Elanco might make for a bourbon distillery would not be suitable for a waste water treatment plant. While the process of exchanging heat remains the same, the purpose the heat exchanger will dictate the exact size and design required.
How Does a Heat Exchanger Transfer Heat?
There are a few different flow arrangements possible for heat abatement. These three arrangements are:
Parallel Flow Configuration. This configuration allows for a one-to-one pass of heat. This means that two fluids enter the exchanger with a large difference in temperature at one end, and travel in parallel to the other end in order to exchange a measure of heat.
Counter Flow Configuration. This configuration allows for a one-to-two pass of heat, in which one fluid enters from one side of the chamber and the second fluid enters from the opposite side. This configuration is believed to currently be the most efficient at heat exchange.
Cross Flow Configuration. As the name implies, this configuration has the two substances traveling in an approximate perpendicular flow.
What Care Does a Heat Exchanger Require For Optimal Performance?
As with any type of mechanical device, a heat exchanger does require maintenance from time to time to function optimally. A common concern with heat exchangers is the risk of the shell and tube configuration fouling, or corroding. This could lead to the pipes leaking one of the fluids, which breaks down the entire purpose of the heat exchanger by failing to keep the two substances separate.
In the case of fouling, a professional technician may recommend either chemical cleaning or mechanical repair. The best choice will depend on the type of heat exchanger and the degree of maintenance required. Maintenance check-ups are recommended to be concluded at least twice a year.
Heat exchangers are a crucial component in modern mechanical devices of all types. To keep them running efficiently, it is vital that problems are caught before they cause fouling. Regularly scheduled checkups can be beneficial in catching minor problems before they require major repairs.