Air conditioning two-stage evaporative cooling. Central Air Conditioning Systems in Buildings p.97 Case Study: Cost Estimate of Indirect Adiabatic Cooling vs. Chiller Cooling

complementary to auth. certificate Kl, V 60 b 3/04 210627 22) Declared on 03.01.7 by attaching the application 3) Priority of the judicial committee of the Minister of the USSR for isotechnical discoveries Bulletin 47 3) Published on 25.1 629,113.06,628.) Date of publication of the description O 3 O 3 V. V. Utkin cooling, an air-content heat exchanger and a pre-chamber for cooling the incoming water exchanger, made with air supply from the heat exchanger. The efficiency of the evaporative cooling is insufficient. external environment , separated by a wavy partition from the air supply channel from the heat exchanger, while both channels are made tapering in the direction of the nozzle chamber inlet. Fig. 1 shows the proposed air conditioner, a longitudinal section; in fig. 2 - section along A-A in Fig. 1. The air conditioner consists of a fan 1 driven by a motor 2; a water-air heat exchanger 3 and a night chamber nozzle 4 equipped with a drop catcher 5. Two rows of nozzles 6 are installed in the nozzle chamber 4. The nozzle chamber has an inlet 7 and an outlet 8 and air channel 9. For water circulation in the first stage, a water pump 10 is installed coaxially with the engine, which supplies water through pipelines 11 and 12 from tank 13 to nozzles 6. In the second stage of the air conditioner, a water pump 14 is installed, which supplies water through pipelines 15 and 16 from the tank 17 to the spray device 18, which wets the irrigated tower 19. A drop catcher 2 O is also installed here. is cooled, and part of it is sent to the second stage (main flow), and part through channel 9 - to the nozzle chamber 4, Channel 9 is made smoothly tapering towards the inlet of the nozzle chamber, due to which the flow rate increases into the gaps 21 between the channel 9 and through the inlet of chamber 7, outside air is sucked in, increasing the mass of the auxiliary flow, which, after passing through chamber 4, is released into the atmosphere through opening 8. serviced space, The water circulating in the first stage is heated in t heat exchanger 3, is cooled in the nozzle chamber 4, separated in the droplet eliminator 5 and flows back into the tank 13 through the hole 22. cooling, mainly for. 4 of a vehicle containing a water-to-air heat exchanger and a nozzle chamber for cooling the water entering: a heat exchanger of water made with an air supply channel from the heat exchanger, differing in that, in order to increase the efficiency of evaporative cooling, a nozzle chamber for cooling the incoming the water heat exchanger 10 is provided with a channel for supplying air from the external environment, separated by a partition from the air supply channel from the heat exchanger, while both channels are made tapering towards 15 the inlet of the chamber. 2. Air conditioner according to claim 1, characterized by the fact that the partition is made in a wave-like manner.

Application

1982106, 03.01.1974

SPECIALIZED DESIGN BUREAU FOR SPECIAL CATERER TRACTORS OF 2T DRIVING CLASS

Utkin Vladimir Viktorovich

IPC / Tags

Link code

Two-stage evaporative cooling air conditioner

Related Patents

13 - 15 heat exchangers 10 - 12 are connected with the cavity A of the casting chamber 16, the cavity B of which is connected by pipeline 17 with the kingston channel 3. The collector 6 is hydraulically connected to the tank 18, which is connected by pipeline 19 with the casting chamber 16, which has an outboard opening 20 and hole 21 in the partition between cavities A and B. The system works as follows. The cooling pump 4 receives water entering the kingston channel 3 through the jumper 2 from the kingston box 1, and delivers it through pressure pipes 5 and 7 - 9 through the collector 6 to the heat exchangers 10 - 12, of which the heated water through the outflow pipelines 13 - 15 enters the cavity A of the outflow chamber 16. When the cavity A is filled, the water overflows through the hole 21 into ...

Ea due to thermal radiation from the surface of the heated strip directly to working surface refrigerator located above and below the processed metal with maximum slope factors radiation, Figure 1 shows a device for cooling strips in a thermal furnace, section B-B in figure 2; ia Fig. 2 chamber for convective cooling of the strip, section A-A in Fig.1; in Fig.3 is the design of the annular gas nozzle. The device for cooling the strip 1 moving along the Rollers 2 is installed in the thermal unit after the radiative cooling chamber 3 and is sealed when the strip exits with a gate 4. Cylindrical water-cooled surfaces 5, circulation fan 6...

6 with oil coolers 7 and 8 and fresh water and branch 9 with a charge air cooler 10 and a muffler 11. Water from branch 6 is drained through a drain kiigston 12, and from branch 9 - through a pipe 13 into the side pipe 14 of the muffler 11. Automatic hydraulic resistance 15 installed on branch 6 consists from a body 16 of variable flow section, a cone-shaped plate 17 with a stem 18, a guide sleeve 19 fixed to the body 16 by uprights 20, a spring 21 and adjusting nuts 22. and pumps it along branch 6 to coolers 7 and 8 of oil and fresh water. On another parallel branch 9, water is supplied to the cooler ...

Union of Soviet

Socialist

Republics

State Committee

USSR for Inventions and Discoveries (53) UDC 629. 113. .06.628.83 (088.8) (72) Inventors

V. S. Maisotsenko, A. B. Tsimerman, M. G. and I. N. Pecherskaya

Odessa Civil Engineering Institute (71) Applicant (54) TWO-STAGE EVAPORATION AIR CONDITIONER

COOLING FOR VEHICLE

The invention relates to the field of transport engineering and can be used for air conditioning in vehicles.

Air conditioners for vehicles are known, containing an air slotted evaporative nozzle with air and water channels separated from each other by walls of microporous plates, while Bottom part nozzle is immersed in the liquid tray (1)

The disadvantage of this air conditioner is the low efficiency of air cooling.

The closest technical solution to the invention is a two-stage evaporative cooling air conditioner for a vehicle, containing a heat exchanger, a tray with liquid in which a nozzle is immersed, a chamber for cooling the liquid entering the heat exchanger with elements for additional cooling of the liquid and a channel for supplying air from the external environment to the chamber , made tapering towards the inlet of the chamber (2

In this compressor, elements for additional air cooling are made in the form of nozzles.

However, the cooling efficiency in this compressor is also insufficient, since the limit of air cooling in this case is the temperature of the wet bulb of the auxiliary air flow in the sump.

10 in addition, the well-known air conditioner is structurally complex and contains duplicate units (two pumps, two tanks).

The purpose of the invention is to increase the degree of cooling efficiency and compactness of the device.

The goal is achieved by the fact that in the proposed air conditioner the elements for additional cooling are made in the form of a heat exchange baffle located vertically and fixed on one of the chamber walls with the formation of a gap between it and the chamber wall opposite to it, and

25, on the side of one of the surfaces of the partition, a reservoir is installed with liquid flowing down the said surface of the partition, while the chamber and the tray are made in one piece.

The nozzle is made in the form of a block of capillary-porous material.

In FIG. 1 shows a schematic diagram of an air conditioner, Fig. 2 raeeee A-A in Fig. one.

The air conditioner consists of two stages of air cooling: the first stage is cooling the air in the heat exchanger 1, the second stage is cooling it in the nozzle 2, which is made in the form of a block of capillary-porous material.

A fan 3 is installed in front of the heat exchanger, driven by a 4 ° electric motor. The heat exchanger 1 is installed on the pallet 10, which is made in one piece with the chamber

8. A channel adjoins the heat exchanger

11 for supplying air from the external environment, while the channel is made as a plan tapering towards the inlet 12 of the air cavity

13 chambers 8. Inside the chamber there are elements for additional air cooling. They are made in the form of a heat exchange partition 14, located vertically and fixed on the wall 15 of the chamber opposite the wall 16, relative to which the partition is located with a gap. The partition divides the chamber into two communicating cavities 17 and 18.

A window 19 is provided in the chamber, in which a droplet eliminator 20 is installed, and an opening 21 is made on the pallet. stream L

In connection with the implementation of the channel 11 tapering to the inlet 12 ! cavity 13, the flow rate increases, and outside air is sucked into the gap formed between the said channel and the inlet, thereby increasing the mass of the auxiliary flow. This flow enters the cavity 17. Then this air flow, having rounded the partition 14, enters the cavity 18 of the chamber, where it moves in the opposite direction to its movement in the cavity 17. In cavity 17, a film 22 of liquid flows down the partition towards the movement of the air flow - water from reservoir 9.

When the flow of air and water come into contact, as a result of the evaporative effect, the heat from the cavity 17 is transferred through the partition 14 to the film 22 of water, contributing to its additional evaporation. After that, a stream of air with a lower temperature enters the cavity 18. This, in turn, leads to an even greater decrease in the temperature of the baffle 14, which causes additional cooling of the air flow in the cavity 17. Therefore, the temperature of the air flow will again decrease after rounding the baffle and entering the cavity

18. Theoretically, the cooling process will continue until its driving force becomes zero. In this case, the driving force of the evaporative cooling process is the psychometric difference -temperatures of the air flow after turning it relative to the partition and coming into contact with the water film in cavity 18. Since the air flow is pre-cooled in cavity 17 with a constant moisture content, the psychrometric temperature difference of the air flow in the cavity 18 tends to zero when approaching the dew point. Therefore, the limit of water cooling here is the dew point temperature of the outside air. The heat from the water enters the air flow n the cavity 18, while the air is heated, humidified and through the window 19 and the drop eliminator 20 is released into the atmosphere.

Thus, in chamber 8, the flow-through movement of heat-exchanging media is organized, and the separating heat-exchange partition allows indirect pre-cooling of the air flow supplied for cooling water due to the process of water evaporation. The cooled water flows down the partition to the bottom of the chamber, and since the latter is made in one whole with a pallet, then from there it is pumped into the heat exchanger 1, and is also spent on wetting the nozzle due to intracapillary forces.

Thus, the main air flow L .n, having been pre-cooled without changing the moisture content in the heat exchanger 1, enters the nozzle 2 for further cooling. without changing its heat content. Further, the main air flow through the opening in the pan

59 yes cools, while cooling the partition. Entering the cavity

17 of the chamber, the air flow, flowing around the partition, is also cooled, but without changes in moisture content. Claim

1. An air conditioner for a two-stage evaporative cooling for a vehicle, containing a heat exchanger, a liquid substation into which a nozzle is immersed, a chamber for cooling the liquid entering the heat exchanger with elements for additional cooling of the liquid, and a channel for supplying air from the external environment into the chamber, made tapering in direction to the camera inlet, different from the fact that, in order to increase the degree of cooling efficiency and the compactness of the compressor, the elements for additional air cooling are made in the form of a heat exchange baffle located vertically and fixed on one of the walls of the chamber with the formation of a gap between it and the opposite wall of the chamber, and on the side of one of On the surfaces of the partition, a reservoir is installed with liquid flowing down the said surface of the partition, while the chamber and the tray are made as one whole.

The use of air conditioning systems (ACS) with evaporative cooling as one of the energy efficient design solutions modern buildings and structures.

Today, the most common consumers of heat and electrical energy in modern administrative and public buildings are ventilation and air conditioning systems. When designing modern buildings for public and administrative purposes in order to reduce energy consumption in ventilation and air conditioning systems, it makes sense to give special preference to reducing power at the stage of obtaining specifications and reducing operating costs. Reducing operating costs is most important for facility owners or tenants. There are many ready-made methods and various measures - to reduce energy costs in air conditioning systems, but in practice, the choice of energy-efficient solutions is very difficult.

One of the many ventilation and air conditioning systems that can be classified as energy efficient is the evaporative air conditioning system discussed in this article.

They are used in residential, public, industrial premises. The process of evaporative cooling in air conditioning systems is provided by nozzle chambers, film, nozzle and foam devices. The systems under consideration can have direct, indirect, as well as two-stage evaporative cooling.

Of these options, the most economical air-cooling equipment is the direct-cooled system. For them, it is assumed to use standard technology without the use of additional sources artificial cold and refrigeration equipment.

circuit diagram air conditioning systems with direct evaporative cooling is shown in fig. one.

The advantages of such systems include minimum costs maintenance of systems during operation, as well as reliability and structural simplicity. Their main disadvantages are the impossibility of maintaining the parameters of the supply air, the exclusion of recirculation in the serviced premises and dependence on external climatic conditions.

Energy consumption in such systems is reduced to the movement of air and recirculated water in adiabatic humidifiers installed in the central air conditioner. When using adiabatic humidification (cooling) in central air conditioners, it is required to use water drinking quality. The use of such systems may be limited in climatic zones with a predominantly dry climate.

Areas of application for air conditioning systems with evaporative cooling are objects that do not require precise maintenance of the heat and humidity conditions. Usually they are run by enterprises of various industries, where necessary cheap way cooling of internal air at high heat intensity of premises.

Next option economical cooling of air in air conditioning systems - the use of indirect evaporative cooling.

A system with such cooling is most often used in cases where the parameters of the indoor air cannot be obtained using direct evaporative cooling, which increases the moisture content of the supply air. In the "indirect" scheme, the supply air is cooled in a heat exchanger of a recuperative or regenerative type in contact with an auxiliary air stream cooled by evaporative cooling.

A variant of the scheme of the air conditioning system with indirect evaporative cooling and the use of a rotary heat exchanger is shown in fig. 2. Scheme of SCR with indirect evaporative cooling and the use of recuperative type heat exchangers is shown in fig. 3.

Air conditioning systems with indirect evaporative cooling are used when supply air is required without dehumidification. The required parameters of the air environment are supported by local closers installed in the room. The determination of the supply air flow is carried out in sanitary standards, or according to the air balance in the room.

Air conditioning systems with indirect evaporative cooling use either outside air or extract air as auxiliary air. In the presence of local closers, the latter is preferred, since it increases the energy efficiency of the process. It should be noted that the use of exhaust air as auxiliary air is not allowed in the presence of toxic, explosive impurities, as well as a high content of suspended particles that pollute the heat exchange surface.

Outside air as an auxiliary flow is used when the flow of exhaust air into the supply air through the leaks of the heat exchanger (that is, the heat exchanger) is unacceptable.

The auxiliary air flow before being supplied for humidification is cleaned in air filters. The layout of the air conditioning system with regenerative heat exchangers has greater energy efficiency and lower equipment cost.

When designing and selecting schemes for air conditioning systems with indirect evaporative cooling, it is necessary to take into account measures to regulate the processes of heat recovery in cold period year in order to prevent freezing of heat exchangers. Reheating of the exhaust air in front of the heat exchanger, bypassing part of the supply air in the plate heat exchanger and speed control in the rotary heat exchanger should be envisaged.

The use of these measures will prevent freezing of heat exchangers. Also in the calculations when using exhaust air as an auxiliary flow, it is necessary to check the system for operability in the cold season.

Another energy-efficient air conditioning system is the two-stage evaporative cooling system. Air cooling in this scheme is provided in two stages: direct evaporative and indirect evaporative methods.

"Two-stage" systems provide for more precise adjustment of air parameters when leaving the central air conditioner. Such air conditioning systems are used in cases where a deeper cooling of the supply air is required compared to cooling in direct or indirect evaporative cooling.

Air cooling in two-stage systems is provided in regenerative, plate heat exchangers or in surface heat exchangers with an intermediate heat carrier using an auxiliary air flow - in the first stage. Air cooling in adiabatic humidifiers is in the second stage. The basic requirements for auxiliary air flow, as well as for checking the operation of SCR during the cold season, are similar to those applied to SCR schemes with indirect evaporative cooling.

The use of evaporative cooling air conditioning systems allows you to achieve better results that cannot be obtained with refrigeration machines.

The use of SCR schemes with evaporative, indirect and two-stage evaporative cooling allows, in some cases, to abandon the use of refrigeration machines and artificial cold, as well as significantly reduce the refrigeration load.

Through the use of these three schemes, the energy efficiency of air treatment is often achieved, which is very important in the design of modern buildings.

History of evaporative air cooling systems

For centuries, civilizations have found original methods of dealing with the heat in their territories. An early form of cooling system, the "wind catcher", was invented many thousands of years ago in Persia (Iran). It was a system of wind shafts on the roof that caught the wind, passed it through the water and blew cool air into interior spaces. It is noteworthy that many of these buildings also had yards with large water supplies, so if there was no wind, then as a result of the natural process of water evaporation hot air, rising up, evaporated water in the yard, after which the already cooled air passed through the building. Nowadays, Iran has replaced wind catchers with evaporative coolers and uses them extensively, and the Iranian market, due to the dry climate, reaches a turnover of 150,000 evaporators per year.

In the US, the evaporative cooler was the subject of numerous patents in the 20th century. Many of them, starting as early as 1906, proposed the use of wood shavings as a spacer, carrying a large amount of water in contact with moving air and supporting intense evaporation. Standard design from the 1945 patent includes a water reservoir (usually fitted with a float valve for level control), a pump to circulate water through the woodchip pads, and a fan to blow air through the pads into the living quarters. This design and materials remain central to evaporative cooler technology in the US Southwest. In this region, they are additionally used to increase humidity.

Evaporative cooling was common in aircraft engines of the 1930s, such as the engine for the airship Beardmore Tornado. This system was used to reduce or eliminate the heatsink, which would otherwise create significant aerodynamic drag. External evaporative cooling devices have been installed on some vehicles to cool the passenger compartment. Often they were sold as additional accessories. The use of evaporative cooling devices in automobiles continued until wide use vapor compression air conditioning.

The principle of evaporative cooling is different from that of vapor compression refrigeration, although they also require evaporation (evaporation is part of the system). In a vapor compression cycle, after the refrigerant inside the evaporator coil has evaporated, the refrigerant gas is compressed and cooled, condensing under pressure into liquid state. Unlike this cycle, in an evaporative cooler, water is evaporated only once. The evaporated water in the cooling device is discharged into the space with cooled air. In the cooling tower, the evaporated water is carried away by the air flow.

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5. Uchastkin P.V. Ventilation, air conditioning and heating at light industry enterprises: Proc. allowance for universities. - M.: Light Industry, 1980. 343 p.
6. Khomutsky Yu.N. Calculation of an indirect evaporative cooling system // World of Climate, 2012. No. 71. pp. 174–182.
7. Tarabanov M.G. Indirect evaporative cooling of supply air in ACS with closers // ABOK, 2009. No. 3. pp. 20–32.
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Ecology of consumption. The history of the direct evaporative cooling air conditioner. Differences between direct and indirect cooling. Evaporative Air Conditioner Applications

Cooling and humidifying the air through evaporative cooling is a completely natural process in which water is used as a cooling medium and heat is efficiently dissipated in the atmosphere. Simple laws are used - when a liquid evaporates, heat is absorbed or cold is released. Evaporation efficiency - increases with increasing air speed, which provides forced circulation of the fan.

The temperature of dry air can be substantially lowered by the phase change of liquid water into steam, and this process requires much less energy than compression cooling. In very dry climates, evaporative cooling also has the advantage of increasing the humidity of the air when it is conditioned, and this creates more comfort for the people in the room. However, unlike vapor compression refrigeration, it requires permanent source water, and in the process of operation constantly consumes it.

History of development

For centuries, civilizations have found original methods of dealing with the heat in their territories. An early form of cooling system, the "wind catcher", was invented many thousands of years ago in Persia (Iran). It was a system of wind shafts on the roof that caught the wind, passed it through the water, and blew cool air into the interior. It is noteworthy that many of these buildings also had yards with large water supplies, so if there was no wind, then as a result of the natural process of water evaporation, hot air, rising up, evaporated water in the yard, after which the already cooled air passed through the building. Today, Iran has replaced wind catchers with evaporative coolers and uses them extensively, and the market due to the dry climate reaches a turnover of 150,000 evaporators per year.

In the US, the evaporative cooler has been the subject of numerous patents in the twentieth century. Many of whom, since 1906, have proposed the use of wood shavings as a pad to carry a large amount of water in contact with moving air, and to support intense evaporation. The standard design, as shown in the 1945 patent, includes a water tank (usually fitted with a float valve for level control), a pump to circulate water through the wood chip spacers, and a fan to blow air through the spacers into the living quarters. This design and materials remain central to evaporative cooler technology in the US Southwest. In this region, they are additionally used to increase humidity.

Evaporative cooling was common in aircraft engines of the 1930s, such as the engine for the airship Beardmore Tornado. This system was used to reduce or completely eliminate the radiator, which otherwise could create significant aerodynamic drag. In these systems, the water in the engine was pressurized with pumps that allowed it to heat up to over 100°C, since the actual boiling point is pressure dependent. Superheated water was sprayed through a nozzle onto an open pipe, where it instantly evaporated, taking its heat. These tubes could be located below the surface of the aircraft to create zero drag.

External evaporative cooling devices have been installed on some vehicles to cool the passenger compartment. Often they were sold as additional accessories. The use of evaporative cooling devices in automobiles continued until vapor compression air conditioning became widespread.

The principle of evaporative cooling is different from that of vapor compression refrigeration, although they also require evaporation (evaporation is part of the system). In a vapor compression cycle, after the refrigerant inside the evaporator coil has evaporated, the refrigerant gas is compressed and cooled, condensing under pressure into a liquid state. Unlike this cycle, in an evaporative cooler, water is evaporated only once. The evaporated water in the cooling device is discharged into the space with cooled air. In the cooling tower, the evaporated water is carried away by the air flow.

Evaporative Cooling Applications

Distinguish evaporative air cooling direct, oblique, and two-stage (direct and indirect). Direct evaporative air cooling is based on the isenthalpy process and is used in air conditioners during the cold season; in warm time it is possible only if there is no or slight moisture release in the room and a low moisture content of the outside air. Bypassing the irrigation chamber somewhat expands the boundaries of its application.

Direct evaporative air cooling is advisable in dry and hot climates in the supply ventilation system.

Indirect evaporative air cooling is carried out in surface air coolers. To cool the water circulating in the surface heat exchanger, an auxiliary contact apparatus(cooling tower). For indirect evaporative cooling of the air, it is possible to use devices of the combined type, in which the heat exchanger performs both functions simultaneously - heating and cooling. Such devices are similar to air recuperative heat exchangers.

Cooled air passes through one group of channels, the inner surface of the second group is irrigated with water flowing into the pan, and then sprayed again. Upon contact with the exhaust air passing in the second group of channels, evaporative cooling of the water occurs, as a result of which the air in the first group of channels is cooled. Indirect evaporative air cooling makes it possible to reduce the performance of the air conditioning system compared to its performance with direct evaporative air cooling and expands the possibilities of using this principle, because. the moisture content of the supply air in the second case is less.

With two-stage evaporative cooling air use sequential indirect and direct evaporative cooling of the air in the air conditioner. At the same time, the installation for indirect evaporative air cooling is supplemented with an irrigation nozzle chamber operating in the direct evaporative cooling mode. Typical spray nozzle chambers are used in evaporative air cooling systems as cooling towers. In addition to single-stage indirect evaporative air cooling, a multi-stage one is possible, in which deeper air cooling is carried out - this is the so-called compressorless air conditioning system.

Direct evaporative cooling (open cycle) is used to reduce the air temperature using the specific heat of evaporation, changing the liquid state of water to a gaseous one. In this process, the energy in the air does not change. Dry, warm air replaced by cool and moist. The heat from the outside air is used to evaporate the water.

Indirect evaporative cooling (closed loop) is a process similar to direct evaporative cooling, but using a certain type of heat exchanger. In this case, moist, cooled air does not come into contact with the conditioned environment.

Two-stage evaporative cooling, or indirect/direct.

Traditional evaporative coolers use only a fraction of the energy needed by vapor compression refrigeration or adsorption air conditioning systems. Unfortunately, they raise the humidity to an uncomfortable level (except in very dry climates). Two-stage evaporative coolers do not increase humidity levels as much as standard single-stage evaporative coolers do.

In the first stage of a two-stage cooler, the warm air is cooled indirectly without increasing humidity (by passing through a heat exchanger cooled by evaporation from the outside). In the direct stage, pre-cooled air passes through the water-soaked pad, cools down further, and becomes more humid. Since the process includes a first, pre-cooling stage, the direct evaporation stage requires less moisture to reach the required temperatures. As a result, according to manufacturers, the process cools air with relative humidity in the range of 50 to 70%, depending on the climate. In comparison, traditional cooling systems raise the humidity of the air to 70 - 80%.

Purpose

When designing the central supply system ventilation, it is possible to equip the air intake with an evaporative section and thus significantly reduce the cost of air cooling in the warm season.

In the cold and transitional periods of the year, when air is heated by supply heaters of ventilation systems or indoor air by heating systems, the air heats up and its physical ability to assimilate (absorb) into itself increases, with an increase in temperature - moisture. Or, the higher the air temperature, the more moisture it can assimilate into itself. For example, when the outside air is heated by a heater with a ventilation system from a temperature of -22 0 C and a humidity of 86% (outside air parameter for the KhP of Kiev), to +20 0 C - the humidity drops below the boundary limits for biological organisms to unacceptable 5-8% air humidity. Low humidity air - negatively affects the skin and mucous membranes of a person, especially those with asthma or lung diseases. Air humidity normalized for residential and administrative premises: from 30 to 60%.

Evaporative air cooling is accompanied by the release of moisture or an increase in air humidity, up to a high saturation of air humidity of 60-70%.

Advantages

The amount of evaporation – and thus heat transfer – depends on the outside wet bulb temperature which, especially in summer, is much lower than the equivalent dry bulb temperature. For example, on hot summer days when dry bulb temperatures exceed 40°C, evaporative cooling can cool water down to 25°C or cool air.
Since evaporation removes much more heat than standard sensible heat transfer, heat transfer uses four times less air flow compared to conventional methods air cooling, which saves a significant amount of energy.

Evaporative cooling versus traditional ways air conditioning Unlike other types of air conditioning, evaporative air cooling (bio-cooling) does not use harmful gases (freon and others) as refrigerants that harm environment. It also consumes less electricity, thus saving energy, Natural resources and up to 80% operating costs compared to other air conditioning systems.

disadvantages

Poor performance in humid climates.
An increase in air humidity, which in some cases is undesirable - the output is a two-stage evaporation, where the air does not come into contact and is not saturated with moisture.

Principle of operation (option 1)

The cooling process is carried out due to the close contact of water and air, and the transfer of heat into the air by evaporating a small amount of water. Further, the heat is dissipated through the warm and moisture-saturated air leaving the unit.

Principle of operation (option 2) - installation on the air intake

Evaporative Cooling Plants

Exist Various types evaporative cooling units, but they all have:
- a heat exchange or heat transfer section permanently wetted with water by spraying,
- a fan system for forced circulation of outside air through the heat exchange section,