What is a Heat Exchanger and How Does is Work?
Have you ever heard of heat exchangers? If not, you’re not alone. Maybe you’ve heard of evaporators or condensers, but what about heat exchangers? You might be wondering why anyone would need to know about these parts of the AC. It’s interesting to learn about them because these parts will help you understand how your AC system works. Read on to find out more about how they function.
What Is a Heat Exchanger?
A heat exchanger is a device that transfers the heat from one fluid to another fluid. The fluids may be of different temperatures or have other chemical potentials.
This device changes the direction of a fluid flow, allowing it to transfer thermal energy from one area to another. It does this using two separate fluid circuits connected by tubing and passing through opposite directions.
You can use heat exchangers in domestic and industrial heating and cooling applications. For example, an automobile radiator uses a heat exchanger to transfer heat from the hot coolant inside the engine to the air outside the vehicle.
What Is a Heat Exchanger Used For?
Heat exchangers have several functions, including:
- Air conditioning and refrigeration systems to transfer heat from the inside of a home or building to the outside using air ducts
- Water heating systems generate hot water from cold water
- Various heating, ventilation, and air-conditioning (HVAC) systems in cars, trains, and aircraft regulate temperature
- Space heating for homes and businesses because heat exchangers transfer heat from the warm interior to the cooler exterior
- In chemical plants where raw materials are heated and cooled and chemicals and mixtures of chemicals are heated and cooled
What Are the Different Types of Heat Exchangers?
There are different types of heat exchangers.
1. Shell-and-Tube Heat Exchangers
These heat exchangers consist of a shell and a tube bundle. The shell side contains a series of tubes to transfer heat from a process. The body is a bundle of tubes or pipes that move the heat from one point to another.
It sits outside the system being heated or cooled. Shell and tube heat exchangers have an advantage in that one size can be purchased for many different techniques because you can customize them for every application.
When cooling, the process fluid passes through the tubes in the shell side, which transfers the heat out to the cooling medium coming in contact with them. When heating, process fluid passes through the pipes inside the shell while hot medium passes through the tubes on the shell side.
Shell and tube exchangers are not as efficient as plate exchangers when transferring large amounts of heat from one place to another because they have dead spots that don’t pass any fluid when they cool or operate in heating mode.
2. Plate Heat Exchangers
A plate heat exchanger is a heat exchanger that transfers heat between fluids through convection and conduction. The liquids are usually within tubes, plates, or both. Plate heat exchangers transfer or exchange heat between two fluids or gases under moderate pressure.
Its design is very versatile, and you can use it for all types of fluids. It consists of tubes that are separated by plates. The heat exchanger is supported on a frame with openings at each end to allow fluid flow into the unit. Heat transfer occurs through the plates, usually corrugated for enhanced performance.
The plate heat exchanger is made up of a series of parallel plates. Each plate has one or more passageways that allow the fluids to flow through, creating a large surface area for the two liquids to mix. The fluids then transfer energy as they flow across the plates.
3. Double Pipe Heat Exchangers
This type of heat exchanger is made of metal plates or tubes that have been welded together to form a series of interconnected passages. A double pipe heat exchanger also has two different fluids flowing through the pipes. A dual pipe heat exchanger can be either external or internal.
Double pipe heat exchangers are heat exchangers in which the fluids remain separated by a double wall. They are often modular and are used in parallel configurations within a system. This flexibility makes them especially well-suited for use in recuperative applications.
4. Condensers Evaporators and Boilers
Boilers, condensers, and evaporators are heat exchangers that use a two-phase (liquid and gas) transfer mechanism.
Condensers are heat exchangers that transfer heat to fluids, changing gases or liquids into gas or liquid. Evaporators and boilers are condensers that change fluids from liquid form to gas or vapor.
An air-cooled condenser is a heat exchanger designed to transfer most of the heat from the flue gases, which are usually hot because of combustion, to the outdoor air.
A water-cooled or water-filled air-cooled condenser is specifically designed to transfer the heat from hot flue gases to cooling water flowing through it. Condensers can be air-cooled, water-cooled, or air/water-cooled.
How Do Heat Exchangers Work?
In a heat exchanger, there are two systems of circulating fluid, each going through its cycle. The first fluid is the working fluid, which is a liquid or gas being heated or cooled. The second is a separate coolant that transfers its heat to or from the working fluid to maintain it at a constant temperature.
The term “heat exchanger” is often associated with the process of cooling something. But it can be used in reverse to warm an area up, too. For example, when you convert natural gas to electricity in a power plant, the steam created is then transferred into underground pipes that run along the ground, where it’s used to heat homes.
Heat exchangers require some form of liquid that will absorb the heat produced by one item and then transfer that heat into something else.
Additionally, they transfer heat from one substance to another, cooling down one sense while heating another. For example, in an air conditioner, a heat exchanger transfers heat from the air outside to the refrigerant inside the machine.
If you are using a furnace to warm up your house, the furnace produces heat that has no way of getting into the air inside of your home. A heat exchanger uses water or another liquid so that you can transfer the heat from one thing into something else.
A heat exchanger consists of three main components, which include:
- The shell: It is the outer casing of the heat exchanger. The body is usually made from steel.
- Heat transfer coils: These transfer heat from one fluid to another fluid through a process known as conduction.
- The media: This is usually a metal mesh or wire designed to allow gas or liquid to pass through it. Heat transfer coils and the media are often called the “fill.”
The shell and fill are enclosed within a case that protects them from external pressures and provides support. The case is iron, aluminum, steel, brass, or copper.
Heat exchangers can take on many different forms depending on their application; however, they all serve the primary function of transferring heat away from one fluid to another.
For more information about heater exchangers, air conditioning services, and heating repair and furnace maintenance services, visit us or request service at Integrity Heating & Cooling. We also attend to any emergency services in Charlotte, NC. Don’t hesitate to get in touch with us today.Heat Exchanger