Heat exchanger and principles of its operation
If you want to learn how a heat exchanger works and what it's used for, we invite you to read the article below. A heat exchanger is a device that enables efficient heat exchange between two substances at different temperatures. This is particularly useful in central heating systems, where heat is transferred from radiators to the air in the room. Thanks to the heat exchanger, it is possible to achieve the optimal temperature in each room, sometimes even reducing energy consumption, resulting in savings. Learn more and check how the plate heat exchanger works.
Theory of heat conduction in a heat exchanger
✅The flow of energy in a heat exchanger is based on the laws of physics. The main principle on which every heat exchanger operates is the fact that heat always flows from a warmer medium to a cooler one. For heat flow and equilibrium to occur in the system, there must be a temperature difference between the two media.
A fluid, whether liquid or gas, at a higher temperature releases its heat to a fluid at a lower temperature. This process aims to equalize temperatures and maintain a stable temperature in the heat exchange system. Heat transport in any heat exchanger occurs through the transfer of internal energy from one material to another through conduction.
Operating principle of any heat exchanger
A heat exchanger is a device designed to transfer heat from one medium to another. We distinguish two basic types of heat exchangers:
- direct - in which both media have direct contact with each other (e.g., industrial cooling tower, where water is cooled by direct contact with air),
- indirect - in which heat exchange between media takes place without their direct contact (media are separated from each other, e.g., by a metal plate - as in a plate heat exchanger).
In the following paragraphs, we will answer the question of what it is, what it is used for, and how a plate heat exchanger works.
Plate heat exchanger - what is this device?
✅A plate heat exchanger is a device that enables efficient heat exchange between fluids at different temperatures. The operation of this device is based on the processes of convection and heat conduction. It consists of a series of thin plates, each with a specially designed structure. The walls of these plates are soldered (using copper solders with excellent thermal conductivity) or twisted together, creating channels through which fluids flow. The plate heat exchanger is made of high-quality stainless steel 316L, which provides durability and corrosion resistance. Thanks to its design and the use of appropriate materials, the plate heat exchanger is a reliable tool for effective thermal energy transfer.
Plate Heat Exchanger - Operating Principle
The plate heat exchanger is a device used in heating and cooling systems, enabling efficient heat exchange between two fluids. The operating principle is based on passing one fluid through channels inside the plates of the exchanger, while the second fluid flows on the other side of the plates. This allows heat transfer between the fluids, facilitating heating or cooling of the medium in the system.
✅The plate heat exchanger is an efficient solution because it has a large heat exchange surface area relative to its volume. This makes significant energy savings possible. Additionally, the plate heat exchanger increases the efficiency of heating and cooling systems by optimizing the heat exchange process. It's worth noting that the plate design allows for easy customization of the exchanger to specific user needs, such as fluid flow or thermal parameters. Therefore, plate heat exchangers are versatile solutions applicable in various industries, including chemical, food, and energy.
Moreover, plate exchangers can be successfully used in both heating and cooling installations. Research and experience indicate that plate heat exchangers are an effective way to optimize energy processes based on heat exchange. Thanks to their advantages, it's possible not only to save heat and energy but also to improve efficiency and minimize heat loss.
Types of Plate Heat Exchangers - Operating Principles Depending on Application
✅ Plate heat exchangers are commonly used to connect gas boilers to central heating systems. They are particularly popular for condensing boilers, which utilize condensate formed during gas combustion. Plate heat exchangers effectively transfer heat from the furnace to the water supplying the central heating system.
✅ Plate heat exchangers are also an ideal solution in all buildings equipped with solid fuel boilers, such as coal, pellets, or wood boilers. Thanks to their design, they ensure efficient heat exchange resulting from the combustion of solid fuels, ensuring installation safety and energy savings. The plate heat exchanger connected to a solid fuel boiler removes excess hot water from the boiler, preventing the system from overheating.
✅ Heat exchangers in the case of heat pumps are used to divide the hydraulic system into two circuits (glycol and water), eliminating the need for glycol (which protects the installation from freezing) throughout the entire system. This solution results in significant cost savings. Theoretically, it's also possible to separate a water-filled heat pump installation, although in practice, this solution is less common. However, the device not only ensures the non-mixing of media from the two circuits but also divides the system into two smaller sub-units, which provide a better hydraulic environment with improved pressure and temperature balance, ensuring a better environment for circulation pumps. In short, such an installation operates much more efficiently.
❎It's worth noting that a heat pump installation requires the use of a larger plate heat exchanger than in the case of a conventional central heating boiler. The larger size of the exchanger increases the efficiency of heat exchange, allowing for the transfer of a greater amount of thermal energy from one medium to another. Consequently, the heat pump can effectively utilize renewable energy, such as ground energy, to provide adequate heating or cooling for spaces. Selecting the appropriate exchanger for a heat pump is demanding, and it's definitely worth consulting with professionals, as it requires a significantly larger plate area compared to selection for boilers or fireplaces with similar nominal power in kW.
✅ Plate heat exchangers are an ideal solution for fireplaces operating in an open system. With them, you can effectively harness the heat generated by the fireplace to heat rooms or domestic water. Plate heat exchangers are easy to install and maintain, providing high efficiency and energy savings.
✅ Plate heat exchangers are essential for separating electric boilers from the installation. They enable precise transfer of thermal energy to water. These exchangers consist of plates made of high-quality materials that allow for efficient heat transfer. As a result, electric boilers become more efficient and economical, leading to energy and operational cost savings.
✅ Plate heat exchangers are also incredibly useful in homebrewing during the cooling of beer wort. The larger the exchanger, the shorter the cooling process, as a larger heat exchange surface allows for faster energy transfer. Therefore, using plate heat exchangers is an excellent solution for homebrewers who want to shorten the cooling time and improve process efficiency.
✅This is a special, extraordinary type of a plate heat exchanger, which requires a different durability, especially agains high pressure. This type of exchanger is destinated for work with freons, refrigerants and F-gases, which tend to achieve the pressure over 40 bar. This required a longer brazzing process. Some of the examples you can find below: