For a long time it was believed that the Earth from the harmful effects of cosmic radiation is mainly protected by its strong magnetic field. But recently, scientists have proven that this is not so - our main "anti-radiation" shield is the atmosphere. Thus, it turned out that the origin of life is also possible on exoplanets that do not have a magnetosphere.

It is traditionally believed that it is the magnetosphere that saves life on our planet from the effects of destructive cosmic radiation. Based on this, scientists, discussing the possibility of the emergence of life on other planets, adhere to the "magnetospheric" criterion of habitability - if the planet's magnetic field is poorly developed, then this celestial body falls into the category of uninhabited, even despite the presence of all other conditions favorable for biological evolution . Thus, in the list of potentially uninhabited by today there are quite a lot of exoplanets located near stars belonging to red dwarfs.

The point here is that if a planet is in the habitable zone of a red dwarf, then it, by definition, cannot have a strong magnetosphere. The aforementioned habitable zone in such a system is so close to the star that an exoplanet that has fallen into it will be constantly subjected to tidal gravitational capture from the side of the star, and this factor, together with others, leads to the fact that it can only have a very weak magnetic field at best. . But if this is true, then it turns out that most exoplanets in the Universe should be completely lifeless - after all, these celestial bodies are most often found near red dwarfs, which are the most widespread stars.

On the other hand, the assumption that it is the magnetosphere that saves terrestrial life from cosmic radiation is still completely unproven, that is, it sins with excessive "theoreticism". At the same time, there are facts that cast doubt on the validity of this hypothesis - for example, recently scientists from the Helmholtz Association of German Research Centers (FRG) found out that the last time the Earth's magnetic poles changed places was not 780, but only 41 thousand years ago, that is, during the life of our biological species. However, the then flora and fauna of our planet, not to mention the human race, did not react in any way to the fact that the magnetosphere at that time was extremely weakened, because when the poles change, the power of the magnetic field drops at least twenty times. And yet, existence for 250 years in an ultra-weak magnetic field did not lead to mass extinctions of terrestrial living beings from destructive cosmic radiation.

It turns out that the magnetosphere is not at all the most powerful protective screen that saves all life on our planet from deadly cosmic radiation? In order to find out, an employee of the Earth Institute (USA), Dr. Dimitra Atri, decided to build a model that takes into account the level of radiation on the surface of the Earth, Mars and planets with atmospheric and magnetic field parameters that are intermediate between these two bodies. Moreover, Mars was included in this model not by chance - our neighbor has a very unstable magnetic field, and its atmosphere is many times rarer than on Earth. That is why the level of cosmic ray radiation on the Red Planet poses a serious threat to the existence of many living beings there, including us.

The results of such modeling turned out to be quite unexpected. As Dr. Atri himself says: “It turned out that the thickness of the atmosphere is a much more important factor in determining the dose of radiation received by the planet, compared to the magnetic field. That is, if you take the Earth and completely remove its magnetic field, then the level of radiation ... will increase by only "Just twice. This, of course, is a lot, but such an effect will nevertheless be small and will not have any effect on living beings. Simply put, they will not notice it at all."

At the same time, the scientist reports, if, on the contrary, the Earth’s very powerful magnetic field is left as it is in the norm, and instead we begin to reduce the thickness of the atmosphere, then already at one tenth of the current value, the radiation dose received by us will increase 1600 times! Moreover, according to the model data, this effect is practically not related to what gases the atmosphere consists of - if, for example, we replace nitrogen in our atmosphere with carbon dioxide (which is dominant in the air envelope of Venus), then the efficiency of penetration of cosmic rays will change no more than than a few percent. It is interesting, by the way, that it is similar to the aforementioned Venus that the surface of the planet protects from cosmic radiation precisely its superdense atmosphere, since the magnetic field of the planet second from the Sun is not much stronger than that on Mars.

Thus, we can safely say that the magnetosphere is not the main and most powerful shield of the planet against cosmic radiation. Accordingly, now we can safely add to the list of potentially habitable exoplanets those that are close to red dwarfs - if anything can interfere with the development of life on them, then it is definitely not the weakness of the magnetic field. However, there may be one more "but" - it is possible that a strong magnetosphere is necessary for the existence of large reservoirs on the planet.

For example, the reconstruction of the history of Venus accepted by most scientists today suggests that it was precisely because of the absence of a magnetic field that the planet lost its water. It happened like this - after the photolysis of life-giving moisture, that is, its decomposition into oxygen and hydrogen under the influence of intense sunlight (after all, Venus is closer to the star than the Earth), the solar wind "carried out" both of these elements from the atmosphere of our neighbor, and a weak magnetic field couldn't stop it. The question arises - can something like this happen on exoplanets of red dwarfs, because they are often "moved" to their stars at an even closer distance?

Climate

Weather and climate. Climate-forming factors and processes.

The weather is what we see outside the window, or when we go outside, we feel it on ourselves. The weather can be warm, cold, overcast. Its condition depends on air temperature, humidity, precipitation, atmospheric pressure, cloudiness, wind. If we observe the weather in one area for several years in a row, its main changes during the year, then we can already talk about the climate of this area.

CLIMATE [gr. klima tilt (of the earth's surface to the sun's rays)], a statistical long-term weather regime, one of the main geographical characteristics of a particular area. The main features of the climate are determined

Impact of geographical factors on K. Climate-forming processes occur under the influence of a number of geographical factors, the main of which are: 1) Geographic latitude, 2) Altitude above sea level. 3) Distribution of land and sea. 4) Orography. 5) Ocean currents. 6) The nature of the soil, 7) Vegetation cover 8) Snow and ice cover 9) Air composition.

The concept of "climate" is much more complicated than the definition of weather. After all, the weather can be directly seen and felt all the time, it can be immediately described in words or figures of meteorological observations. To get even the most approximate idea of ​​the climate of the area, you need to live in it for at least a few years.

CLIMATE FORMING PROCESSES - processes in the atmosphere that form the climate of the Earth, a natural zone or a separate region. They occur in three directions: 1 - heating of the Earth by solar rays (radiation) and heat exchange of its surface with the atmosphere; 2 - general circulation of the atmosphere; 3 - moisture circulation between the atmosphere and the earth's surface.

Three reasons (factors) also influence the climate formation of each region: 1 - the number solar radiation, which depends on the latitude of the area; 2 - the movement of air masses (circulation of the atmosphere) and 3 - the nature of the underlying surface.

The structure of the atmosphere. Layers of the atmosphere and their main features.

1. The atmosphere consists of several layers that differ from one another in temperature and other conditions. The lower part of the atmosphere, up to a height of 10-15 km, in which 4/5 of the entire mass of atmospheric air is concentrated, is called the troposphere. It is characterized by the fact that the temperature drops with height by an average of 0.6 C/100m. The troposphere contains almost all of the water vapor, and almost all clouds form. Turbulence is highly developed, especially near the earth's surface, as well as in jet streams in the upper part of the troposphere.

The height of the troposphere depends on the latitude of the area and on the season of the year. On average, the height above the poles is 9 km, in temperate latitudes 10-12 km, above the equators 15-17 km. The air pressure at the upper boundary of the troposphere is 5-8 times less than at the earth's surface. Therefore, most of the air is in the troposphere. The lowest layer, several tens of meters directly adjacent to the ground, is called the surface layer. The layer from the earth's surface to a height of 1000-1500m is called the friction layer.

2. Above the troposphere up to a height of 50-55 km lies the stratosphere, characterized by the fact that the temperature in it increases on average with height. The transition layer between the troposphere and stratosphere is called the tropopause. The lower stratosphere is more or less isothermal (the temperature almost does not change with height). But starting from a height of about 25 km, the temperature rapidly increases with height, reaching maximum, positive values ​​(from +10? to +30?) at an altitude of 50 km. Due to the increase in temperature, turbulence in the stratosphere is low. There is little water vapor. However, at an altitude of 20-25 km in high latitudes, mother-of-pearl clouds are sometimes observed. The stratosphere is also characterized by the fact that it mainly contains atmospheric ozone. The increase in temperature with height in the stratosphere is explained precisely by the absorption of solar radiation by ozone.

3. Above the stratosphere lies a layer of the mesosphere, up to about 80 km. Here the temperature drops with height to several tens of degrees below zero. Because temperature drops rapidly with height, then turbulence is developed in the mesosphere. Noctilucent clouds can be observed at altitudes close to the upper boundary of the mesosphere (75-90 km).

4. The upper part of the atmosphere, above the mesosphere, is characterized by a very high temperatures and hence is called the thermosphere. It has two parts: the ionosphere and the exosphere, which passes into the earth's corona. The air in the ionosphere is very rarefied. The layer is characterized by a strong degree of air ionization. The electrical conductivity of the atmosphere depends on the degree of ionization. Therefore, the electrical conductivity in the ionosphere is many times greater than that of the earth's surface. Radio waves experience refraction, absorption and reflection in the ionosphere. It is due to reflection from the ionosphere that long-range communication at short waves is possible. In the ionosphere, polar lights, the glow of the night sky, and ionospheric magnetic storms are observed. The temperature in the ionosphere at altitudes of about 800 km reaches 1000°C. Atmospheric layers above 800-1000 km are distinguished under the name of the exosphere. The speed of movement of gas particles, especially light ones, is very high here. Individual particles have sufficient speed to overcome gravity. They can escape into world space, dissipate. Therefore, the exosphere is also called the sphere of scattering. It is predominantly hydrogen atoms that escape, which is the dominant gas in the high layers of the exosphere. Hydrogen escaping from the exosphere forms an Earth's corona around the Earth, extending to more than 20,000 km. In the upper part of the atmosphere and near-Earth space, the Earth's radiation belt

Solar radiation

Solar radiation- electromagnetic and corpuscular radiation of the Sun.

The electromagnetic component of solar radiation propagates at the speed of light and penetrates into the earth's atmosphere. Solar radiation reaches the earth's surface in the form of direct and diffuse radiation. In total, the Earth receives from the Sun less than one two-billionth of its radiation. The spectral range of the Sun's electromagnetic radiation is very wide - from radio waves to X-rays - however, its maximum intensity falls on the visible (yellow-green) part of the spectrum.

There is also a corpuscular part of solar radiation, consisting mainly of protons. During solar flares, high-energy particles (mainly protons and electrons) are also formed, which form the solar component of cosmic rays.

The energy contribution of the corpuscular component of solar radiation to its total intensity is small compared to the electromagnetic one. Therefore, in a number of applications, the term "solar radiation" is used in a narrow sense, meaning only its electromagnetic part.

Solar radiation is the main source of energy for all physical and geographical processes occurring on the earth's surface and in the atmosphere (see Insolation). The amount of solar radiation depends on the height of the sun, the time of year, and the transparency of the atmosphere. Actinometers and pyrheliometers are used to measure solar radiation. The intensity of solar radiation is usually measured by its thermal effect and is expressed in calories per unit area per unit of time (see Solar constant).

Influence of solar radiation on climate

Spectrum of radiation of energy by various bodies and on the surface of the Sun.

Solar radiation strongly affects the Earth only in the daytime, of course - when the Sun is above the horizon. Also, solar radiation is very strong near the poles, during the polar days, when the Sun is above the horizon even at midnight. Solar radiation is not blocked by clouds, and therefore still enters the Earth. Solar radiation is a combination of the bright yellow color of the Sun and heat, heat also passes through clouds. Solar radiation is transmitted to Earth through radiation, and not through heat conduction.

The amount of radiation received by a celestial body depends on the distance between the planet and the star - as the distance doubles, the amount of radiation coming from the star to the planet decreases by a factor of four. Thus, even small changes in the distance between the planet and the star lead to a significant change in the amount of radiation entering the planet. Much more strongly the amount of incoming solar radiation depends on the changes of the seasons - at present total solar radiation reaching the Earth remains virtually unchanged.

Undoubtedly, the sun is not only a symbol of joy, warmth and life. The sun is revered by all peoples at all times, as an irreplaceable and necessary "element" of the existence of all life on Earth. However, both scientists and doctors warn that as much as the sun's rays are useful for all living things, they can be so dangerous. First of all, this, of course, concerns lovers of sunbathing, and even more so without taking any precautions. Excess ultraviolet rays can cause irreparable harm to human health.

The level of danger depends on the intensity of solar radiation and the amount of time that a person is outdoors. The higher the level of solar radiation on the Earth's surface, the greater the degree of risk. People who work under the sun or often sunbathe should also take into account the characteristics of their skin, that is, its type. Skin type can be determined by eye and hair color. The first type includes people with blue eyes and reddish hair. The second type is characterized by light blond hair and blue or bluish-green eyes. The third type of skin is typical for people with dark blond or brown hair with gray or grayish-brown eyes. Burning brunettes with brown eyes fourth type of skin.

Thus, for residents of temperate latitudes, the optimal amount of time spent in the sun can be determined precisely by the type of skin. People with the first and second type of skin should not be outdoors during periods of increased solar activity for more than 30 minutes. For the third and fourth types, the safe time will not be 45-50 minutes. AT southern countries this time should be halved. Experts warn that not all help protect the skin. Firstly, no type of cream guarantees that you will not "burn out". Secondly, creams and ointments will definitely not save you from exposure to solar radiation.

It is worth considering another nuance - this is the choice of sunglasses. Plastic ones will definitely not save you from the negative effects of the sun on your eyes. Real, or rather safe glasses, should be sold with a mark on the content of UV-B and UV-A filters. Such filters will not let dangerous radiation through. Even glass glasses from a supposedly good manufacturer will not be able to protect your eyes. The protection mechanism in the eyes is triggered when the pupil narrows reflexively from the bright sun. In the situation of poor quality glasses, the retina will not be protected and harmful ultra-violet rays strike even more.

• UV-C RADIATION recognized as the most dangerous to humans. Such rays do not reach the Earth's surface, as they are absorbed by the ozone layer. This radiation is capable of killing all the cells of the human body. Radiation from lasers, electric welding is no less dangerous than real solar UV-C radiation. We must try as far as possible to protect ourselves from such a danger and protect our health.
• UV-B RADIATION not completely absorbed by the ozone layer, according to scientists of the Earth reaches about 6% of such rays. Burns, skin tumors, cancer diseases- these are all the consequences of the latter.
• UV-A RADIATION reaches the Earth in full, but not as dangerous as the above. Scientists have identified the UV index by the level of danger to humans, which ranges from 1 to 10 units. The minimum degree of risk for a person is 0-2 conventional units, the most dangerous is 10.

Thus, given all of the above, you can protect yourself from the harmful effects of sunlight and thus not put your health at risk.

Modern public buildings with facade glazing consume on average more energy for air conditioning in summer than for heating in winter. It is not surprising that in recent times More and more attention is paid to the problem of protecting buildings from heat losses.

Structural solar protection

In order to gain control over rapidly increasing energy costs, work was underway to improve the energy-saving parameters of products used in construction. These were new designs of window frames and windows with insulated heat-shielding glass; highly efficient boiler plants; controlled residential ventilation systems; constructive prevention of cold bridges; creation of hermetic shells of buildings. All this was aimed at minimizing heating costs and had its positive results. But in addition to heating buildings in winter, a lot of energy resources were spent on air conditioning in the summer months. This was required by large areas of glazing facades of modern buildings, which are subject to overheating. This is not to say that protection from the thermal effects of sunlight was not used. But was it effective? The answer to this question can be found in Table 1. The trend of modern glass architecture paints a completely different picture. The influx of solar heat, which passively reduces heating costs in winter, exposes building occupants to significant overheating in summer and affects well-being and productivity, resulting in higher air conditioning costs. This problem can be solved by constructive protection from solar radiation - built-in facade or hinged sun protection systems - as the most effective ways protection from solar heating. They can effectively influence the amount of solar heat entering a building through insolation. The main goal is not to exceed the maximum indoor climate values ​​with minimal use of air conditioning and mechanical ventilation. Incoming solar radiation, which causes heat to flow into the premises through windows, is reduced through the use of installations solar protection.

Determining the maximum values ​​of solar radiation heat input depends on various influencing factors, such as the climate of the region, the thermal conductivity of building enclosing structures, ventilation of rooms at night. From this it becomes clear that the values ​​​​of summer sun protection must be taken into account in advance when designing. For optimal selection and implementation of solar shading devices, it is necessary to understand the physics of the sun. The data of the position of the sun, its current projection on the façade surfaces as well as the calculation of the thermal loads are a necessary set of data for the calculation of sun protection devices.

Differentiation when equipping facades

A simple and effective solution is the use of horizontally mounted, visor-shaped plate systems (lamellas). First of all, they are suitable for southeast and southwest facades. For the southern facades in the summer months, the location of the complete shading of the window surfaces is chosen, when there is no direct sunlight entering the window. At the same time, the decrease in the inflow of heat from solar radiation is about 76%. And although the south-eastern facades in the morning are not completely shaded due to the low standing sun, window shading reduces the heat load by up to 69%. The outdoor sunshade is a cost-effective, maintenance-free, long-term façade design solution. Along with a decrease in summer overheating of buildings, such a structure simultaneously forms its appearance. If for the southern facades it is sufficient to use fixed sun protection devices, then for the eastern and western facades, due to a significant change in the angle of the sun's movement (from surface to direct insolation at the daytime solstice), the use of fixed sun protection systems does not solve the problem of shading. In this case, it is better to use mobile solar shading systems, which are used in case of serious overheating of the premises, when it is necessary to solve the problem of the comfort of people's stay. Modern constructive sun protection performs the following tasks:

• dimming or reducing direct sunlight;
• significant minimization of summer heat load;
• obtaining natural daylight;
• maintaining visual comfort;
• solar shading at high wind speed;

Tab. #1
Reduction factor for solar radiation penetration FC from permanently built-in sun protection devices

Without protection devices	1,00
Protective devices located inside or between window panes
white or reflective surfaces with little transparency	0,75
light color and slight transparency	0,80
dark color and high transparency	0,90
outside
rotating plates, slightly open	0,25
blinds and materials with slight transparency, ajar	0,25
blinds	0,40
block and window shutters	0,30
canopies, loggias, freely installed plates	0,50
awnings ventilated at the top and side	0,40

• preservation of passive solar radiation in winter;
• optional incoming light control function for daylight room lighting; optional photovoltaic use
• solar energy;
• figurative relief design of facades.

Thus, constructive sun protection is a tool to achieve comfortable conditions staying indoors while saving energy. On fig. 3 shows the principle of operation of an outdoor horizontal movable sun protection installation, which is a series of movable plates. But in addition to horizontal ones, vertical movable plates are also used. The following values ​​refer to plates made of green glass:
-solar heat remains outside due to reflection and absorption, convective cooling of the plates occurs;
- At the same time, natural daylight in the room is achieved. This is especially important in rooms with high comfort requirements, such as workplaces with displays, as the use of sunscreens avoids glare and optimally combines workplace comfort with effective energy savings.

With the help of movable plate systems equipped with devices for adjusting and tracking the position of the sun, it is possible to achieve an optimal distribution of the flow of heat, light and air into the room. Various sun tracking concepts are used to control the moving plate systems: CCS 2000 Solar Control or Soltronic calendar tracking systems, which calculate the position of the sun at a given moment. Depending on the local external weather conditions, which are recorded by the corresponding sensors, the plates are installed in the following required position:

• in the shading position (the plates rotate with the course of the sun);
• to the position of controlling the flow of light (for lighting rooms);
• in a diffuse position (the plates are maximally open in a gloomy sky);
• to the adjustment position (possibility of closing the plates in winter to reduce the cooling of the building);
• in the position of building security (closing the plates, creating an additional barrier against burglary).

Depending on the needs of the user, the multilateral profile parameters of the moving plate control system are adjusted. The plates move automatically, completely silently and consistently, with natural inertia and according to the position of the sun. The energy of the tracking systems, which sets the systems in motion depending on the position of the sun, has the following properties:

• environmentally friendly, free from radiation;
• without cabling;
• does not require a front break for impulse tubes;
• has a silent drive;
• has natural inertia (does not react to a small cloud);
• brings automatic calculation to heterogeneous façade irradiation and offers easy commissioning.

The principle of operation of the tracking system: cylinders and two absorber elements form a hydraulic system. Depending on the different direction of the sun's rays, different heating of the absorbers occurs. The temperature and associated differential pressure cause the bulb to move, which rotates the plates to match the position of the sun. Plates are made from various materials. These can be extruded aluminum profiles (painted or not), screen glass and even textile membranes. Plate systems (photovoltaics) with the additional use of solar energy are of particular use. Here, a symbiosis of solar protection and active use of solar energy is achieved. The tracking system that controls the plates simultaneously solves the problem of optimal exposure of the sun's rays to the photovoltaic cells of the solar panels located on the plates, which makes it possible to achieve an efficient conversion of the influx of solar energy. The shown possibilities of summer thermal protection through constructive solar protection cannot be considered alone. When designing for optimal indoor comfort and energy savings at the same time, a complete solution must be sought. It follows from this that it is necessary to use air conditioning only when all construction and technical measures have been exhausted to achieve the desired internal temperature and other comfort criteria. In other words, thermal protection is not only a winter, but also a summer theme! In addition, constructive solar protection is about more than just reflecting the sun's rays. This is a new tool for architects and designers that allows not only to protect the building from overheating, but also to find the individual plasticity of building facades. This is well demonstrated by the 11-storey building in Frankfurt, the building - a prism, owned by a design company (architect Auer - Weber - Partner, Stuttgart). Usually, a transparent glass structure leads to overheating of the building in the summer. In this case, the triangular roof of the patio, having an area of ​​about 3000 m 2 , is fully glazed. A third of the roof is equipped with movable plates. Thus, the shading and light guide plates that are equipped with a glass roof, as well as the huge areas of glazing of the double facade, form the glass case of the building, which creates additional advantages for solving ventilation and energy equipment issues.

Taking into account the specific requirements, aesthetic appearance, good aerodynamics, special plates with an elliptical shape were used here for installation. The plates are 400 mm wide and 60 mm thick. In the position of dispersion of the light flux, the plates look like thin lines on the glass. Since the designers were tasked with achieving at least 90% of the degree of reflection, a strong aluminum foil with a thickness of about 0.5 mm was applied to the plates with a high reflective effect. For weather protection, the plates are covered with a thin acrylic film, which makes them easy to clean. Solar protection, natural lighting, building air conditioning are controlled and regulated by the intelligent control system Colt CCS 2000 Solar Control. At each unit of time, the microprocessor calculates the exact position of the sun and sets the optimal shading angle with the help of light, rain and temperature sensors and controls the flow of light. The system automatically moves to the dim or diffuse position. After processing the data from the sensors, various modes can be launched: storm start, frosty weather, cleaning, etc. A large number of additional production functions can be included in the control, such as day, night and holiday modes. The prism building project is a great example of combining environmental aspects with sustainable use of energy resources, showing how solar protection complements the architecture of a building. Another striking example is the public and industrial building of the Grunewald company in Bocholt (Germany), behind the facade of which there are production and administrative premises. The authors of the project are prof. Jorg Ruedemer (Berlin) and engineer Joachim Leson (Bucholt). Support structures: Giesers StahLbau GmbH. Its unusual shape, resembling a pipe, and elements of the building's solar protection attract attention, and most importantly - reflect the direction of the enterprise. The Grunewald company is engaged in mold casting, tool production, as well as the manufacture of polystyrene formwork molds and, along with this, polymer structures used in aircraft construction. From the very beginning, it was planned to equip the building with household technical devices to ensure maximum comfort in the workplace with the condition of optimal energy consumption. Within a few months, consultative and design work was carried out, as a result of which it was decided to use glass plates and plate windows as natural ventilation and solar protection devices for this enterprise, and facade photovoltaic systems as an additional source of energy.

It should be noted that the decision was considered and made by the customer for several months, and, in the end, the project was accepted with virtually no changes. Thus, such facade structures as solar panels on the end facade and movable glass sun-reflecting plates became an integral part of the building. At first, the use of arc-shaped curved plates was rejected in favor of glass plates, since, along with significant cost savings, it is optically easier to model a curved facade surface by means of segmented plate parts. Special attention was paid to the shape and type of plates. Along with energy calculations, the technical possibilities of natural daylight and also the visual design were evaluated. The choice fell on green glass (VSG - connection) with a 50% thin white dot coating. To maintain the symmetry of the building, the northwestern façades were also equipped with a system of glass plates. At the beginning of the project, a variant of a fixed arrangement of plates was proposed, which was subsequently replaced by automated movable controlled plates, since the calculation showed that additional costs could be compensated within the energy concept of the project. The overall supporting structure for the solar plate system is made of stainless steel, specially machined and polished. The built-in façade balcony makes it possible to carry out maintenance and cleaning work on the internal façade and the external plate system. The Colt CCS 2000 Solar Control system, which monitors the position of the sun and manages the building security system, sets the plates exactly to the position of the sun, taking into account weather conditions. The system independently manages large façade surfaces and groups of differently oriented surfaces. For additional energy, the project uses solar panels built into the southeast end facade. This orientation is optimal for the use of solar energy. Four photovoltaic generators together give a power of 13.64 kW. The produced solar energy is supplied through four converters to the local electrical grid. The photovoltaic panel is integrated into the transom post like conventional insulated panes, with the cable hidden in the side bar. Along with elements of natural smoke and heat removal, glass lamellar windows at the bottom of the facade and on the northwest side of the building are used as supply ventilation.

The plant in Bocholt is a new milestone in the modern equipment of the building, which allows for maximum functionality along with the rational use of energy resources.

In the open air, the surfaces of products are exposed to direct

sun rays. In materials used in system designs,

under the action of solar radiation, complex processes occur that cause the aging of these materials. In addition, solar radiation is the main factor in the formation of the thermal regime of the atmosphere and the earth's surface. Therefore, the influence of high and low air temperatures on the properties of materials is ultimately determined by the influence of solar radiation on the thermal regime of air.

The arrival of solar radiation is determined primarily by astronomical factors: the length of the day and the height of the sun. Solar radiation reaching the earth's surface is one of the main climatic factors. In turn, it largely depends on the circulation of the atmosphere and the characteristics of the underlying surface.

The impact of solar radiation on technical products is determined

the range of electromagnetic waves reaching their surface.

The spectrum of energy emitted by the Sun consists of several parts.

The waves of the ultraviolet part of the spectrum (_ _ _____10–10 m) account for

about 9% of the energy of solar radiation, into the waves of the visible part of the spectrum

(_ = 3900_10–10...7600_10–10 m) - about 41% and for infrared waves

(_ = 7600_10–10...1000000_10–10 m) - about 50%.

The atmosphere surrounding the Earth absorbs about 19% of the sun's energy.

(water vapour, ozone, carbon dioxide, dust and other constituents of the atmosphere). About 35% of the energy is absorbed in outer space. Only 45% of solar energy reaches the Earth's surface, but the presence of clouds reduces the amount of solar energy reaching the Earth by about 75% compared to clear days.

Surface heat flux density of total radiation

depends on the cloud cover. Depending on the height of the sun (6-44.9°)

in the summer months, the total radiation flux changes in cloudless weather from 11.2_10–3 to 78.4_10–3 W/cm2, in the presence of the sun and clouds -

in 9.8_10–3 to 80.5_10–3 W/cm2, in case of continuous cloudiness - from 4.2_10–3

up to 25.9_10–3 W/cm2.

The flux of total radiation also depends on the clouds themselves, if

the sun shines through cirrus clouds, then the total radiation flux

will vary from 4.9_10–3 to 64.4_10–3 W/cm2, if the clouds are stratus

From 3.5_10–3 to 38.5_10–3 W/cm2. Influence on the value of the total

radiation is also exerted by the height of the clouds, if the clouds are high, the flux varies from 5.6_10–3 to 49.7_10–3 W / cm2, if low - from 6.3_10–3

up to 27.3_10–3 W/cm2.

The integral density of the heat flux of solar radiation depends on

from height. Up to 15 km, the integral heat flux density is

1125 W/m2, including ultraviolet flux density

(_ = 280-400 µm) - 42 W/m2, over 15 km - 1380 W/m2, flux density

ultraviolet part of the spectrum - 10.0 W/m2.

The change in the heat flux density of solar radiation is estimated

the ratio of its maximum value to the minimum, expressed

in %. The smallest diurnal changes are observed in desert areas,

which are characterized by cloudiness.

The presence of water vapor and dust in the air significantly reduces the density

heat flux of solar radiation. The strongest action

materials and products are exposed to the sun's rays perpendicularly falling on the surface.

Sun damage can be divided into two groups: photochemical and photo-oxidative processes.

In case of damage to metal surfaces, an essential role is played by

photooxidative degradation. Simultaneous exposure to oxygen

and moisture creates through oxidative processes an additional

amount of energy. The surface of metals under ultraviolet

irradiation is activated, and therefore exposed to the risk of corrosion. For

splitting of the molecular structure requires a certain frequency

radiation, since the photon energy corresponds to the product of the constant

Plank for frequency. Under the action of sunlight, complex photolytic processes occur in organic materials - the processes of decomposition of chemical compounds, as a result of which the properties of materials change.

Solar radiation (especially its ultraviolet part) is sufficient

for the destruction of many, even very strong, bonds in polymer molecules, which causes aging and certain failures. The aging process of polymeric materials is accelerated by heat, moisture, air oxygen (atmospheric aging), high-energy radiation, etc. In turn, the aging rate under the action of solar radiation depends on its intensity, the fraction of ultraviolet radiation in the solar spectrum, and the absorbing ability of polymers. It has been established that the rupture of molecular bonds and the aging processes of most polymers occur at a radiation intensity exceeding 16.8 kJ/(m2_min). It is known that the aging of polymeric materials is based on two simultaneously occurring processes: destruction - breaking bonds between atoms of molecules and the formation of fragments of polymer molecules, and structuring - the formation of new bonds between atoms and fragments of molecules that have arisen as a result of destruction. As a result of aging of polymeric materials

their mechanical and electrical properties, color, etc.

The main effect of solar radiation is heating the surface of products

and, consequently, an increase in the temperature inside the device.

The heating of a body by solar rays depends on the intensity of solar radiation, the ambient temperature and on the reflectivity

body. Being heated, the body itself becomes a source of radiation.

It is convenient to trace the regularity of heat transfer of surfaces on

heat exchange of a thin-walled metal casing. For matte case

black casing, inside which there is no source, the radiation of energy can be represented by the diagram in fig. 3.2.

The shell wall thickness is small, so it can be assumed that the temperatures

the outer and inner surfaces of the walls of the casing are the same. Based on the law of Stefan Boltzmann, we make up the balance of the radiation of the walls of the casing.

The top cover of the casing, which absorbs the heat of the sun's rays, radiates

outside and inside the casing (σ T)

The bottom wall of the casing (bottom) absorbs the heat emitted by the top cover and radiates it into the casing and out (σ T)

When the casing is located on the soil, the lower wall gives off heat to the soil and can receive heat from it (σ T)

At the temperature equilibrium of the system, the following mathematical relationships are valid:

where: TV- casing cover temperature, To;

TD- shell bottom temperature, To;

TS- soil temperature, To;

σ_ - radiation constant (Stefan-Boltzmann constant).