Not so long ago, almost all heat exchangers had a shell-and-tube design, in which the media rush to each other, moving through the tubes. The last elements are placed one inside the other. But today such a heat exchanger device is becoming a thing of the past. Such devices are quite bulky, but they function quite efficiently. Among their shortcomings, a large consumption of the heated medium can be distinguished. Considering the types of heat exchangers, you should notice that today the devices described above are being replaced by new ones - high-speed plate units.
Working principle of plate heat exchanger
Considering the types of heat exchangers, you need to pay special attention to the lamellar variety of such devices. Structurally, such devices differ from the shell-and-tube predecessor. The latter has a surface areaenergy exchange is increased due to the impressive length of the coil, which certainly became the reason for the more impressive dimensions of the device. If we are talking about a new heat exchanger, then the goal is achieved by increasing the number of plates that have the same area. Modern types of heat exchangers have the same power, but they are 3 times smaller in size than shell-and-tube models. New devices provide an impressive flow of the heated medium, which is used for the needs of hot water supply. This led to the fact that the unit acquired a second name - it is called a high-speed heat exchanger. Such devices are composed of return and supply pipes, which are used to connect the heating medium, the coolant acts as the latter.
The device and features of work
The device has outlet and inlet pipes of the heated medium. You can see in the design a fixed plate, which is located in front. There are holes in the device for water to enter. The heat exchanger will not work without a sealing gasket, which is represented by a ring, as well as a heat exchange working plate. There is a rear movable plate and upper guides in the design. The device is equipped with a rear support, a stud and a gasket that is located along the contour of the plate.
The described types of heat exchangers are used for heating a simple design with nozzles that are located on opposite sides of the device. Between the plates, which are on twoguides, a number of plates are clamped with a seal between them. The plates have embossed corrugations to increase the exchange surface. In some models, the connecting pipes are located on one side of the device, they are located on the front plate, which, however, does not affect the functioning of the plate device. Plate heat exchangers work on the principle that involves filling the space between the plates with a heated medium.
Additional information about the work
The shape of the pads determines the sequence of filling: in one section they open the way for water, in the other section they absorb heat. During the operation of the devices of each section, in addition to the last and first, one can notice a rather intense heat exchange through the plate on both sides. The media flow through the sections, heading towards each other. The heating medium enters from above and exits through the bottom pipe. As for the heated medium, it follows the direction opposite to the heating medium.
Varieties of heat exchangers
On sale today you can also find a cast-iron heat exchanger, but there are other devices that are made of other materials. Varieties of such devices are presented in a wide range. Their use is not limited to one area of industry, units are now used everywhere: in metallurgy, chemical industry, energy, at heating points, in systemsheating, air conditioning and ventilation.
Differences in heat transfer method
If you want to install a stove with a heat exchanger, you should first understand the types of devices described in the article. So, they can also be distinguished by the method of heat transfer, in this respect they can be surface and mixing. In the first case, heat exchange occurs between different media through walls made of a heat-conducting special material. At the same time, the circuits remain completely sealed. If you are interested in surface-type equipment, then you should know that there are regenerative and recuperative devices. In the latter case, the temperature exchange between heat carriers occurs through the thin walls of the circuits, while the flow of the medium has the same direction. In the second case, the flow direction may change. If you decide to install a gas heat exchanger, then you should pay attention to the mixing varieties of devices. Heat transfer in them occurs by mixing two media, but devices of this type are used less frequently than those indicated above.
Varieties of heat exchangers by area of use
When the owner of a private or country house decides to install a stove with a heat exchanger, he most often chooses a shell-and-tube system, which consists of a bundle of pipes connected to each other in a grid by welding and soldering. Another variety is lamellarheat exchangers, which were discussed above, they have a heat exchange area, presented in the form of plates. The latter are interconnected by heat-resistant seals. Concentric coils are used for the installation of cast heat exchangers, the working medium in them moves along curved pipes, as well as the space between the pipes.
Not to be overlooked are spiral devices, which are represented by thin metal sheets. They are rolled into spirals during the manufacturing process. The presented list is not complete, among the most common one can also distinguish air and water devices.
The heat exchanger, the price of which can be 7000 rubles, is presented today in a wide variety. It is simply impossible to list all types of such units, so only the most popular ones were presented above. The leader among them is lamellar.
Varieties of plate devices
Plate heat exchangers are offered for sale in a wide range, they can be collapsible, brazed, welded and semi-welded. The first variety was discussed above, but as for the soldered variety, it includes corrugated metal plates made of stainless steel. These elements are connected together by vacuum soldering using nickel or copper solder.
Conclusion
Heat exchanger (price shown above) can also be welded. Such devices are intended for operation in conditions of high temperatures and extreme pressure. They areare used in installations whose parameters do not allow the use of sealing elements.
