The concept of heat exchange minimizes the cost of heating and cooling the serviced environments. In this case, air flows are considered, the characteristics of which determine the parameters of the microclimate in private houses, industrial premises, etc. In practice, the heat exchange is organized by the recuperation system. It acts as a kind of temporary heat accumulator, collecting and releasing its energy. The most commonly used rotary heat exchanger, which is valued for its high performance, flexible settings and other positive qualities.
Design of the heat exchanger
Recuperators are practically not used as independent equipment. Most often they are introduced into supply and exhaust ventilation units, in which the recuperation function is an additional option. The heat exchanger itself is a metal heat exchanger of the regenerative class. The working basis is a cylindrical rotor, the rotation of which leads to the movement of air masses. The rotor is formed by a package of thin plates that accumulate heat. In turn, the supply and exhaust unit with a rotary heat exchanger can be included in a larger engineering network. In simple versions, it acts as a means of air ventilation, and at industrial enterprises it also performs the task of utilizing heat from technological gaseous media. However, the full range of recuperator functions should be considered separately.
Heater functions
The main task is to collect heat for different purposes. Usually - for the subsequent distribution of thermal energy in new incoming air masses, and less often - for its damping. In both cases, a reduction in energy consumption for the use of special heat exchange equipment is achieved. At the same time, the heat exchanger remains a ventilation device that serves to renew the air in the room. Depending on the modification, the rotary heat exchanger can perform air purification and even aromatization. At least getting rid of unpleasant odors is a common property of such devices. More functional models also make it possible to regulate the temperature regime. In this case, the return of the accumulated energy occurs with certain parameters that can be set manually or automatically - again, this depends on the capabilities of a particular model.
Working principle
The action of recuperators of this type is based on the transfer of heat from the outgoing air streams (for example, warmed room air) to the cold masses of fresh air. Passing between the rotor plates, the air warms them, and on the other hand new streetcold air currents and are heated from the accumulated heat. The volumes of outgoing and incoming air are determined by the size and power potential with which the rotary heat exchanger operates. The principle of operation of the unit provides for the interaction of rotating plates with a drive connected to the mains. Just the presence of an electric drive allows you to fine-tune the installation to work with a certain speed mode. On average, the rotation speed is 1 rpm.
Varieties of device
In the standard version, the working mechanism of the heat exchanger is divided into several segments - from 4 to 12. Such models are used to remove excess heat generated as a result of technological operations in enterprises. These are condensing rotors that activate their function when the temperature of the served air falls below the "dew point". The features of condensing units include the ability of metal elements to withstand moisture. High-temperature devices designed to operate at elevated temperatures are also common. A domestic rotary heat exchanger is not designed to eliminate excess heat. Such a mechanism is used precisely for its distribution in fresh air flows. However, similar models also provide for the possibility of regulating heating.
Comparison with plate models
Compared to rotary units, plate models do not have a drive and carry out heat exchange offline. Usercan manually, by changing the direction of the accumulating plates, change only the throughput of the mechanism. From this we can draw conclusions about the pros and cons of both systems. But first, let's talk about the general benefits. Both rotary and plate heat exchangers are small in size and have sufficient capacity. This eliminates the need for additional devices, including power ones. If we talk about the differences, then the rotary mechanism is more flexible in adjustments, free from the risk of freezing in winter and energy efficient. But at the same time, it differs in a more complex device and provides for a certain proportion of mixing of exhaust flows and fresh air.
Installation work
The heat exchanger is installed in the prepared channel of the supply and ventilation system. The housing should not come into contact with the wall, as vibrations can be transmitted to it, which will negatively affect the supporting structure as a whole. It is also recommended to use special anti-vibration protection in the form of damper pads for the heat exchanger. When the support base with legs and profile fasteners is ready, you can begin to integrate the case. Typically, the installation of a rotary heat exchanger is carried out in a special technical unit, sized for a specific model. Fixation is implemented using complete connecting fittings - the basic set includes corners, hardware, seals and linings. Further, auxiliary technologicalcontours. At this stage, the connection is made using fittings, adapters and reducers of the appropriate sizes.
Recuperator control
The rotary mechanism is rarely controlled separately from the main supply and ventilation system. In the latest designs, the possibility of electronic control of the device through the controller panel is used. In automatic mode, the owner can set such parameters as the rotation speed, the percentage ratio between the volumes of air inlet and outlet, the degree of purification, time intervals, etc. The operation parameters of the mechanism are monitored using sensors, which, in particular, record the throughput of the equipment. Also, the supply unit with a rotary heat exchanger can be configured for special operating modes. One of the modern regimes of this type is operation under conditions of maintaining a constant air pressure. This program eliminates the risk of overloading the drive with subsequent overheating.
Device Maintenance
The surfaces of the rotor and the housing itself require regular cleaning. The plates are cleaned and, if necessary, additionally treated with anti-corrosion compounds. You should also regularly check the direction of rotation of the rotor, and in the drive system - the quality of the belt tension. Since the heat exchanger works in close conjunction with other functional ventilation components, it is important to check their condition too. In particular, the filter, air ducts are subject to revisionchannels, dust collectors, valves with sensors, etc. If possible, the rotary heat exchanger will not be superfluous to remove from the installation site and fully check for tightness. The fact is that in the presence of even minor gaps, the quality of the incoming air deteriorates sharply.
Conclusion
The air recovery mechanism is the simplest way to heat a room. Cold outdoor air is preheated with virtually no additional energy consumption. Of course, rotary air recuperators, when connected to the network, consume energy for their function, but it is generally spent on ensuring the circulation of flows. The same example with plate heat exchangers shows how inefficient a unit without an electric drive can be in operation. Also, power supply is required to power the control infrastructure, which ensures the operation of the entire supply and ventilation complex. These are usually minimal costs, but as a result, they greatly simplify the operation of the equipment.
