Ministry of Education of the Russian Federation

Municipal budgetary educational institution

City of Irkutsk secondary school No. 75

Scientific and practical conference

"I'm interested"

EVAPORATION OF MOISTURE BY LEAVES OF DIFFERENT

HOUSE PLANTS

Completed:

Tozhiboev Aziz

5th grade student

municipal budgetary educational institution of the city of Irkutsk, secondary school No. 75,

children's association "Young Researcher" State Autonomous Educational Institution "Center for the Development of Additional Education for Children"

Leaders: Natalya Ivanovna Lebenko, biology teacher of the Municipal Budgetary Educational Institution of the city of Irkutsk, Secondary School No. 75

Khilkhanova Lyubov Nikolaevna,

teacher of additional education, State Autonomous Institution of Educational Institution "Center for the Development of Additional Education for Children"

Irkutsk 2018

Introduction. 3

Chapter 1. Literature review. 3

Chapter 2. Experimental methodology. 5

Chapter 3. Research results. 6

Chapter 4. Conclusions. 8

Bibliography. 8

Introduction

In the 2nd grade, during the “World around us” lesson, we studied plants and were told about their benefits, how they absorb carbon dioxide, purify the air, and absorb water with their roots. In biology lessons we were told what kind of cells there are in plants, their structure, that the cell consists mostly of water. I became interested in the topic of this research work because I was curious about how plants absorb water and where it goes. Before conducting the experiment, I read in the literature that plants absorb water with dissolved minerals from the soil through their roots. Minerals The plant needs it for life and growth. The plants evaporate excess water through their leaves.

Target: determine whether all plants evaporate water equally.

Research objectives:

1. Perform an experiment with different indoor plants on the evaporation of water from the leaves.
2. Conduct an analysis of water evaporation by different plants.

Chapter 1. Literature Review

Transpiration - movement processwater through the plant and herevaporation through external plant organs such asleaves , stems And flowers . Water is essential for plant life, but only a small portion of the water supplied through the roots is used directly for growth andmetabolism . The remaining 99-99.5% is lost through transpiration. The surface of the leaf is covered with pores calledstomata and in most plants most of the stomata are on the lower part of the leaf. Stomata are limitedguard cells and accompanying cells (collectively known as the stomatal complex), which open and close the pores. Transpiration passes through the stomatal slits and can be seen as a necessary "price" associated with opening the stomata for accesscarbon dioxide , necessary forphotosynthesis . Transpiration also cools the plant, changesosmotic pressure in cells and ensures the movement of water and nutrients from roots to shoots.

Water is absorbed by the roots from the soil usingosmosis and moves to xylem to the top along with the nutrients dissolved in it. The movement of water from the roots to the leaves is partially ensuredcapillary effect , but mainly occurs due to the pressure difference.

Cooling is achieved by evaporation of water from the surface of the plant, which has a highspecific heat of vaporization .

Regulation of transpiration

The plant regulates its transpiration rate by changing the size of the stomatal slits. The level of transpiration is also affected by the state of the atmosphere around the leaf, humidity, temperature and sunlight, as well as the state of the soil and its temperature and humidity. In addition, it is necessary to take into account the size of the plant, which determines the amount of water absorbed by the roots and subsequently evaporated through the leaves.

There are many techniques and instruments available to measure plant transpiration levels, includingpotometers , lysimeters , porometers , photosynthetic systems and thermometric sensors.

Desert plants have special devices features that reduce transpiration and conserve water, such as thick cuticles, reduced leaf area, and leaf hairs. Many of them use the so-calledCAM photosynthesis , when the stomata are closed during the day and open only at night, when the temperature is lower and the humidity is higher. .

The plant evaporates water. But how does it get it? The answer is that osmotic pressure (osmosis) and turgor pressure (turgor) are at work. Osmotic pressure is on the cell, and turgor pressure is, on the contrary, out of the cell when it fills with water. This is how water rises from the roots along the stem to the leaves.

Chapter 2. Experimental methodology

The experiment was carried out in December-January of the 2017-18 academic year. To conduct the study, an experiment was conducted.

Equipment: plants, plastic bags, thread.

Scheme of the experiment:

We took four indoor plants from the biology classroom at our school: pelargonium (geranium), Rex begonia, ficus and silver bemeria.

We selected leaves with the same surface area and size, put sealed plastic bags on them and tied them with thread. We placed all the pots with plants on the sunny windowsill of the office. All four plants were watered equally.

Evaporation (transpiration) was observed in different plants.

Data were recorded weekly in a spreadsheet.

Figure 1 Experiment setup.

Chapter 3 Research results.

Table 1. Presence and amount of moisture in plastic bags.

The experiment confirmed that all indoor plants evaporate moisture through their leaves. But evaporation occurs differently in different plants. The most water evaporated from Rex begonia; slightly more moisture was observed from geranium and bemeria. The least amount of water was in the plastic bag on the ficus.

Chapter 3. Conclusions

The research goal wasdetermine whether all plants evaporate water equally. An experiment was carried out on four indoor plants biology classroom at school No. 75. Created same conditions lighting, watering, etc.

During observation for two months, it was determined that transpiration is very weak in the ficus, which is explained by the structure of its leaves. The ficus leaf is covered with a waxy coating - a dense cuticle that protects against excessive evaporation.

Rex begonia has the most active transpiration.

Pelargonium developed water earlier than Bemeria. Bemeria and pelargonium have leaf pubescence, which also protects the leaf from overheating and excess evaporation. But in the end, approximately the same amount of moisture accumulated in these bags.

Thus, we can conclude that in plants transpiration occurs at different rates and this depends on many reasons.

Bibliography

1. Large series of knowledge Biology / Team of authors. – M.: World of Books, 2006.
2. Encyclopedia for children. Biology. Editor-in-Chief Aksenova M. T.2. - M.: Avanta+, 1999.
3. I get to know the world: who is who? In the natural world. Compiled by V.P. Sinchekov, G.P. Shalaeva, E.V. Sitnikova. - M.: Ast Slovo. 2010.
4. Wikipedia [electronic resource] Transpiration https://ru.wikipedia. org/wiki/

A. Margolina, E. Hernandez. "New cosmetology".

Moisturizing creams are a cosmetologist's magic wand.

A lot depends on the moisture content of the skin - its elasticity, firmness, even color. Just by moisturizing the skin, you can completely smooth out fine wrinkles, disappear dark circles under the eyes, and give the skin a lighter shade. It’s no wonder that cosmetic companies are actively using this optical effect. Many anti-wrinkle products are nothing more than well-formulated moisturizers. There would be nothing wrong with all this if cosmetics manufacturers sometimes did not use prohibited techniques, namely, they did not simultaneously include in cosmetic products substances that increase skin permeability (the simplest is sodium lauryl sulfate) and substances that slow down the evaporation of water.

On the one hand, due to the slight swelling that occurs after such remedies, wrinkles magically disappear, the face brightens and acquires youthful swelling. However, systematic use of such products over a long period of time can cause harm to the epidermal barrier. Therefore, if a product produces an instant effect, transforming your face literally before your eyes, it is better not to use it every day, but to put it aside for those occasions when you need to look good.

On the other hand, by maintaining the required level of moisture in the skin, we prevent aging changes, create conditions for the normal functioning of all skin structures, and strengthen its protective properties. And this is no less (if not more) important than periodic “stimulation” of the skin and active interference in its vital functions.

Ways to increase skin moisture.

Slowing down evaporation (occlusion).

Water continuously rises from the depths of the skin to its surface and then evaporates. Therefore, if you slow down its evaporation by covering the skin with something gas-tight, the water content in the epidermis will increase quite quickly. This method is called occlusal(from the English occlusion - barrier, barrier).

If the film is completely impenetrable (for example, polyethylene film), the epidermis will become too wet, which will lead to swelling of the stratum corneum and destruction of the barrier. Rubber gloves and breathable clothing also lead to overhydration. In such cases they say that “the clothes don’t breathe.”

Semi-permeable film, which only slows down but does not completely stop the evaporation of water, will also eliminate the symptoms of dryness without damaging the skin.

Ingredients that slow down water evaporation include:

• Mineral oils, petroleum jelly, liquid paraffin, cesarine - all these are hydrocarbons, petroleum products;
• Lanolin (from Latin lana - wool, oleum - oil) is an animal wax obtained by refining wool wax (it is extracted organic solvents from sheep wool);
• Animal fats – goose fat, whale oil (spermaceti), pork fat;
• Squalene and its derivative squalane (from the Latin Squalus - shark) are a natural component of human sebum; sources of production are different (for example, shark liver, some plants);
• Vegetable oils - mostly solid, for example, shea butter (shea butter);
• Natural waxes and their esters – beeswax, vegetable waxes(coniferous reed, etc.).

The above components vary in occlusion strength. Vaseline is considered the most reliable proven moisturizing component. In dermatology, it is used to moisturize the skin for eczema, psoriasis, atopic dermatitis and other diseases. Disadvantages of Vaseline and other derivatives mineral oil is an unpleasant feeling of heaviness and fatness.

Because Vaseline is too moisturizing, it can slow down the repair of the epidermal barrier - the cells will not receive a signal in time that the barrier needs repair.

Occlusive moisturizers (i.e., those that block the evaporation of moisture) quickly eliminate dry skin, reduce inflammation and itching in skin diseases, but they do not act on the cause of skin dehydration. They can be compared to crutches, which are necessary for those who cannot move independently, but are completely unnecessary for people with normal legs.

If the skin barrier function cannot be restored, occlusive creams are necessary. If there is a chance there is recovery, they should be used only at the initial stage.

There are several categories of cosmetics used when the use of occlusive components is justified. For example, post-peeling care products applied to skin with a damaged barrier after peeling. In such cases, occlusive drugs act as an “ambulance”, maintaining the level of moisture necessary for normal cell functioning during the most acute period.

Children's cosmetics for skin care in the diaper area, where the skin is constantly irritated, should have occlusive properties.

Hand protectants also include occlusive ingredients. No part of the body is subject to such strong attack from the external environment as the hands. The skin on them is constantly injured, even everyday washing with soap (not to mention contact with products household chemicals), containing surfactants, damages the lipid barrier. Applying an occlusive agent will prevent the skin of your hands from drying out and soften it.

It should be noted that almost any moisturizing cream contains components that reduce evaporation due to occlusion. But if in some preparations this is the main component, then in others it is an auxiliary component, and the main role is given to substances that absorb and retain moisture.

Trapping moisture.

The use of substances that can bind and retain water molecules (such compounds are called hygroscopic) is a great way to quickly moisturize the skin. In cosmetics, two categories of hygroscopic compounds are used, acting on the skin in two different ways.

"Wet compress" method.

Some substances adhere to the surface of the skin and absorb moisture like a sponge, forming something similar to a wet compress. This effect is achieved by:

• Glycerol;
• Sorbitol;
• Polyglycols (propylene glycol, ethylene glycol);
• Polysaccharides – hyaluronic acid, chitosan, polysaccharides of plant and marine origin (chondroitin sulfate, mucopolysaccharides), pectins;
• Protein molecules and their hydrolysates (in particular, the popular cosmetic ingredients collagen and elastin are included in cosmetics precisely as moisturizing agents);
• Polynucleic acids (DNA) and their hydrolysates.

This list, among other things, contains substances with large polymer molecules (more than 3000 Da), which, due to their size, are not able to penetrate the stratum corneum.

The listed components are found in almost all cosmetic forms, including emulsion (creams). However, most of them are in gels and “liquid” products (tonics, lotions, serums, concentrates).

And now attention: the use of products that moisturize the skin like a “wet compress” is not always justified.

For example, in a dry climate, when the relative water content in the environment is lower than in the stratum corneum, the compress begins to “pull” water from the skin. As a result, the stratum corneum becomes drier.

On the contrary, at high air humidity, applying cosmetics with these components actually softens and moisturizes the skin. At the same time, it improves appearance skin – it acquires a matte shine, is slightly tightened and smoothed.

By the way, it is thanks to drying that the “compress” has a smoothing effect. High-molecular compounds that adhere to the skin and form something like a mesh on it, themselves compress and pull the skin along with them. The result is a “superficial lifting”, which is declared in the annotations of such cosmetic products. The severity of superficial lifting depends on the degree of drying: the drier the compress, the stronger the lifting (up to the appearance of a feeling of tightness characteristic of dry skin).

To prevent the rapid evaporation of water from the “wet compress,” substances that act as occlusion are added to cosmetic products.

Another option is to use a complementary pair, for example, a moisturizing toner plus a cream. Consistently applying toner first and cream on top will help soften the skin and retain moisture for a longer period.

Note that in professional cosmetics they prefer the second option, because it gives more opportunities in terms of an individual approach to the skin different types and taking into account climatic features.

Method of “Deep” skin hydration.

Some cosmetic products say that they have the effect of deeply moisturizing the skin. What does this mean?

A common misconception is to think that all layers of the skin, including deep ones, are moisturized. In fact, only the stratum corneum is moisturized.

The role of natural sponges in the stratum corneum is played by the components of natural moisturizing factor (NMF) - free amino acids, urea, lactic acid, sodium pyroglutamate. They are located throughout the stratum corneum, and only in it.

Rice. Water-retaining structures of the stratum corneum.

These compounds are formed as a result of the breakdown of proteins (mainly filaggrins) that provide adhesion to the cells lying under the stratum corneum. Having passed into the stratum corneum, the cells not only lose their nucleus, the connections between them are also gradually destroyed (which is why the horny scales that are not attached to each other freely peel off from the surface of the skin).

NMF molecules are located in close proximity to corneocytes. A significant portion of the water present in the stratum corneum is associated with NMF. Bound water is involved in the gluing of horny scales and, along with sebum, ensures the plasticity and smoothness of the skin surface, however, it does not interfere with the disintegration of the scales and their natural removal.

Unlike large high-molecular compounds, NMF components applied as part of cosmetics can penetrate into the thickness of the stratum corneum (but not deeper) and increase its moisture-retaining potential. The hydration that is felt in this case, as a rule, is not as pronounced and does not occur as quickly as with the “wet compress” type, but it lasts longer and is less dependent on air humidity. There is no lifting effect observed.

Moisture-absorbing and retaining agents work best to hydrate the skin either in humid air or when applied directly after a bath or shower. They increase the plasticity of horny scales and reduce the roughness of the skin surface. However, they do not reduce skin irritation or create the same firmness and freshness as occlusive agents. Therefore, in cosmetic formulations they are usually combined with occlusive components.

Restoration of damaged lipid barrier.

Damage to the barrier is one of the causes of dryness.

Damage to the lipid barrier of the stratum corneum (changes in lipid composition, structural changes, destruction) is one of the most common causes of dry skin. The main indicator that the barrier is broken will be an increase in the transepidermal water loss index (TEWL).

Even if a violation of the lipid barrier is not the root cause of the development of dryness, it still occurs if the skin suffers from a lack of moisture for a long time. Therefore, in addition to using moisturizers that relieve the feeling of dryness and increase the moisture content in the stratum corneum, it is necessary to use products designed to restore the barrier.

First of all, damage to the barrier should be patched up fairly quickly with something. For this purpose, lipids are used, both in the form of pure oils and in combination with other ingredients in local preparations.

Lipid molecules penetrate into intercellular spaces and are integrated into the lipid barrier. Some of the lipid molecules applied on top gradually move along the intercellular spaces, reach the living layers of the epidermis and are included in cellular metabolism. In particular, they can serve as a substrate for further lipid synthesis, which is characteristic of the skin barrier.

Substances used to restore the barrier.

Natural oils are mixtures of lipids. Therefore, the restorative efficiency and preferential mechanism of action of oils will depend on their lipid composition. Oils containing essential fatty acids (linoleic and gamma-linoleic) promote accelerated synthesis of lipid barrier components, delivering the necessary lipid precursors directly to the cells (borage oil, evening primrose oil, seeds black currant).

Oils enriched with saturated and monounsaturated fatty acids have more pronounced occlusive properties and help restore barrier properties by hydrating the epidermis (shea butter, lard, macadamia, corn, coconut, cocoa, cashew).

Lipid mixtures composed of physiological lipids - ceramides, cholesterol, and free fatty acids - are very effective. These lipids are called physiological because they constitute the natural lipid barrier of the human stratum corneum. It was experimentally established that their equimolar (i.e. in equal parts) mixture – “ceramides/cholesterol/free fatty acids”—has the best restorative properties.

Micelles, liposomes, lamellas.

It is no coincidence that lipids are one of the most popular cosmetic ingredients. They can be included in formulations both as individual molecules and as structural formations. The latter include, for example, liposomes and micelles. In addition to the traditional role assigned to lipids, such structures act as carriers or containers for other biologically active components, stabilizing them and facilitating penetration through the stratum corneum.

Relatively new technology In cosmetics, the use of so-called lamellar emulsions based on phosphatidylcholine (lecithin) began, in which tiny drops of lipids are stabilized not by conventional emulsifiers, but by a network of biolayers, similar to those that make up the lipid barrier. “Preparations that are structurally appropriate to the skin” is how these cosmetics are often called. They have excellent moisturizing and restorative properties, since they are compatible with the lipid barrier not only in composition, but also in structure, which is especially important in the case of dry or sensitive skin.

Skin with increased permeability is characterized by increased sensitivity to toxic and irritating influences. Therefore, until its barrier layer is restored, it needs protection.

To protect the skin from damaging effects, film-forming substances and antioxidants are used. Good protection for the skin is provided by biopolymers, which form a semi-permeable film on the surface of the skin. These are, first of all, natural polysaccharides - chitosan and hyaluronic acid.

Protecting the lipid barrier from oxidation

Along with mechanical protection The lipid barrier of damaged skin must be protected from peroxidation. To do this, antioxidants are introduced into cosmetics - substances that neutralize free radicals and break oxidation chain reactions.

The most common cosmetic antioxidant is vitamin E, which easily penetrates lipid layers (since it is fat-soluble) and protects them from oxidation.

Water-soluble antioxidants are also used - vitamin C and bioflavonoids (plant polyphenols).

Barrier restoration sequence.

Creams that create a temporary barrier on the surface of the skin partially eliminate the consequences of damage to the epidermal barrier and prevent the development of pathological reactions, but they do not accelerate, and sometimes (especially with long-term use) even slow down the process of barrier restoration.

To bring the skin into normal condition, it is necessary to achieve complete restoration of its structure and functions. If the skin has everything necessary for the synthesis of endogenous lipids (precursor lipids and enzymes), the barrier is completely restored within three days. Otherwise, the skin will need additional help.

Now that the first stress caused by damage to the epidermal barrier has passed, you can apply fatty components (lipids) that will penetrate deep into the skin, supplying cells with the necessary building material.

Since skin cells have everything necessary to disassemble fats into their component parts, there is no fundamental difference in what kind of lipids will be used - the main thing is that they contain the necessary components.

Most often, oils containing essential fatty acids - linoleic, linolenic, gamma-linolenic acid (GLA) - are used to supply the skin with building material. They are used both in cosmetics and in the form of food additives. Oils rich in GLA, such as black currant seeds and borage, have a particularly beneficial effect on the skin.

It should be remembered that the process of skin restoration occurs slowly. Therefore, the effect of using Vaseline, emollients and moisturizers will be more noticeable than the effect of using creams containing essential fatty acids.

Since polyunsaturated fatty acids cannot be a means emergency assistance When the barrier is destroyed, they must be taken regularly to prevent the occurrence of deficiency conditions.

Roughness of the skin, a feeling of tightness, irritation - all this can be relatively quickly eliminated with a combination of emollients. For this purpose, formulations are used that, on the one hand, have average or low spreadability rates (i.e., do not spread well on the skin and are perceived as quite greasy), on the other hand, they must have average absorption rates. In other words, they should be felt on the skin for some time in the form of a thin fatty film.

Emollients (including many oils) somewhat limit the evaporation of water and therefore, like occlusive agents, increase the moisture content of the skin. In addition, they soften the skin and smooth out the horny scales, improving the appearance of the skin. Emollients, strictly speaking, are not moisturizers, since they have little effect on the moisture content of the skin, but they help to significantly reduce the discomfort caused by dry skin.

Irritation from using moisturizers.

Although moisturizers are supposed to reduce skin irritability (i.e. increase its sensitivity threshold), in real life many of them have the exact opposite effect. This is explained by the fact that when the stratum corneum is oversaturated with water (this condition is called hyperhydration), it becomes more permeable, which means that substances that previously did not pass through it can pass through it. Therefore, it is necessary to ensure that moisturizers contain as few substances as possible that could potentially cause skin irritation.

Here is a list of some of these substances:

This list is not complete, since, according to the literature, skin irritation can also be caused by propylene glycol, phenoxyethanol, preservatives that release formaldehyde, almost all essential oils and many other components. That is why, when buying a moisturizer for sensitive, irritation-prone skin, you need to choose one whose formulation contains as few ingredients as possible. If you have a product with 40 or more components, the likelihood that your skin will not like some of them is very high.

Dry skin and nutrition.

It has been repeatedly noted that the skin is not a digestive organ, therefore, it is not so easy to “nourish” it from the outside. Many substances must pass through the digestive system and be exposed to a variety of enzymes before they can be used to feed body cells (and skin cells are no exception). Therefore, along with the use of cosmetics that replenish the deficiency of essential fatty acids and antioxidants, it is useful to make changes to the diet.

This means limiting the consumption of meat and fatty poultry, as well as chips, hamburgers, etc. Instead of meat, you need to learn to eat fatty fish, such as salmon, cod, mackerel. Fish is a source of valuable omega-3 fatty acids, which are necessary to restore the balance of the body's immune system. However, it must be borne in mind that now many species of large predatory ocean fish are recognized as not completely safe for health due to the fact that mercury and other toxins can accumulate in their meat.

Cabbage and carrot salad with butter, fruits (citrus fruits, apples, etc.), and berries (sea buckthorn, blueberries, grapes, etc.) are used as a source of antioxidant vitamins.

Although everything useful material best received as part of food products, rather than in pill form, it is sometimes worth supplementing your diet with nutritional supplements containing essential fatty acids and antioxidant vitamins.

Dry air means dry skin.

One of the most effective ways to combat dry skin is to increase air humidity. It has been experimentally shown that prolonged exposure to dry air leads to damage to the barrier function of the skin, which leads to the development of dry skin.

You can increase air humidity in different ways - buy a humidifier, cover the central heating radiators with a damp cloth, place containers of water, plants with large leaves or an aquarium in the room.

If it is possible to regulate the temperature in the room, then you need to maintain it at a minimum comfortable value.

If dry air is unavoidable, then after each wash or shower, apply a moisturizer to still damp skin.

Moisturizing for skin diseases.

Many skin diseases are accompanied by dry skin. Dermatologists have long noticed that the use of emollients and moisturizers reduces discomfort in a number of skin diseases and even extinguishes the inflammatory reaction.

However, only recently have moisturizers and emollients been recognized as an important aid to the dermatologist in the treatment of skin diseases.

In many skin diseases, the skin is not able to form a complete epidermal barrier, so it does not retain water well and easily allows allergenic and toxic substances to pass through.

In itself, increased evaporation of water through the stratum corneum is already an alarm signal for cells, by which they begin to release signaling molecules, many of which are capable of igniting a fire of an inflammatory reaction in the skin.

At the same time, the systematic use of products that normalize the evaporation of moisture from the skin and create a temporary barrier extinguishes this fire and allows the skin to function normally even with a broken barrier.

Since when the barrier is damaged, the skin is obviously highly reactive, the formulations of cosmetics for people whose dry skin is caused by skin diseases should be the simplest, i.e. contain as few components as possible. In the very simple version this can be well-refined petroleum jelly (it used to be lanolin, but then, due to reports of allergic reactions to lanolin, it was largely abandoned).

There are dermatological compositions containing a suspension of phospholipid liposomes or lamellar emulsions, prepared using a special technology without surfactants, fragrance additives and preservatives.

Moisturizing is a vital part of the corneotherapy approach to solving skin care problems. Its essence is that it is enough to put the stratum corneum in order and maintain it to prolong the youth and health of our skin, help it cope with various skin diseases (if any) in whole or in part, reducing discomfort.

Choosing a suitable moisturizer is not an easy task, and often it cannot be solved immediately, focusing only on the external signs of dry skin. Until recently, choosing a moisturizer was a matter of trial and error. Now, with the advent of special equipment in beauty salons, it is possible to accurately determine the leading link in the pathogenesis of dry skin in a given person and, based on this information, select an individually suitable moisturizer.

Every day, the skin of every person is influenced by various negative factors, such as weather conditions, the environment, and the ecological situation in the region of residence. Most negative impact The skin is exposed to ultraviolet rays when exposed to the open sun or during normal tanning. But the effect of air humidity on the skin is also important, since there are many subtleties here.

Humidity and skin

Of course, every person has noticed that on hot days and dry weather, as well as when exposed to dry wind for a long time, one becomes very thirsty. The body at this time requires a large amount of fluid, as it loses water due to external natural factors and needs to replenish these losses.

However, even when drinking large volumes of liquid in the presence of dry air, skin cells do not have enough moisture to function normally, since it evaporates in large quantities through the skin.

Air humidity is a certain indicator of the amount of water contained in it. This indicator is of particular importance for the general condition of a person and his skin, and also affects the degree of comfort of being indoors or outdoors.

For example, in summer time, on the hottest days, most people find it very uncomfortable to be outside because it is difficult to breathe. This is explained by the fact that when heated, the air is saturated with moisture (its evaporation from the surface of reservoirs and soil), and the higher the air temperature, the greater the volume of water it can absorb. As a result, on hot days, especially if it has rained before, people experience serious discomfort and breathing problems. Of course, this condition also affects the skin, since the heat causes increased sweating, which can lead to serious fluid loss.

About the same thing happens in winter, when there is severe frost outside. During this period, air humidity usually decreases, since due to the low temperature water does not evaporate, but at the same time the air is also ready to accept moisture and absorb it. As a result, in the cold it is very difficult to breathe due to the dry air. With breathing, a lot of steam comes out, the molecules of which are immediately absorbed into the air. As a result, the body loses large volumes of water. The air takes water away from the skin of the face, as well as from other open areas of the body. That is why, after a long stay in the cold, as well as in the heat, the skin becomes dry and dehydrated.

As a rule, if the air temperature is high, but the air humidity is low, people tolerate it much more easily and have less impact on the condition of the skin. At low temperatures accompanied by high levels of air humidity, rapid hypothermia can occur.

What are the dangers of violating the humidity level?

The most comfortable indicators of air humidity for a person’s condition, his health and maintaining proper water balance in the body and in skin cells the value is from 30% to 60%. If the indicators deviate in any direction, this can lead to various negative consequences.

At low air humidity, due to strong evaporation of moisture, the skin very quickly dries out, becomes dehydrated, and begins to peel and crack. As a result, damage to the skin appears, which is not always noticeable to the eye, but, nevertheless, allows free access to the body for a variety of pathogenic microorganisms that can provoke the formation of an inflammatory process and acne, as well as infection with serious diseases.

In addition, when the humidity is too high in the hot season, the body sweats intensely, trying to cool the skin and protect it from overheating, not only losing water, but also forming a sticky film on the surface of the skin, to which dust and other contaminants stick. The result can be not only dehydration of the skin, but also a large number of acne caused by clogged pores and sebaceous ducts.

If the air humidity is high, the body begins to lose heat simultaneously with intense sweating, resulting in a serious risk of overheating. In this case, not only the human skin suffers, but the entire body. With prolonged stay in rooms with high air humidity, a person may experience a general decrease in immunity, which results in not only skin diseases, but also various diseases internal organs, and exacerbation of existing diseases occurs.

Of course, it is impossible to say unequivocally that when the level of air humidity increases or decreases, a person will definitely develop skin problems, since each organism is individual and its reaction to certain environmental changes is simply impossible to predict. Skin reaction different people changes in the environment will be different, while if a certain level of air humidity has a positive effect on the skin of one person, then it may be negative for the skin of another person.

For example, with dry skin, a high level of air humidity will be useful, since the water in the air will become an additional source of hydration of the epidermis. A low level of humidity with dry skin will provoke the appearance of peeling and dehydration. In addition, humidity helps smooth out wrinkles. However, if you have oily skin, high humidity levels can be a factor in causing acne. Therefore, quite often the condition of the skin depends on the air humidity in the apartment or other room.

In most cases, in winter, the air in apartments and houses has a low level of humidity, which is facilitated by the work of various heating devices. As a result, the skin becomes drier, thinner, and may show signs of aging. Therefore in winter period the skin needs additional care, hydration and nutrition. It is also recommended to humidify the air in the apartment, using special air humidifiers or simply placing containers with clean water, the evaporation of which will provide additional humidity.

As a rule, in order to avoid unwanted consequences and complications, cosmetologists recommend adjusting to a certain level of air humidity, providing the skin with the necessary conditions. At low humidity levels, the skin must be treated with creams and other products for deep intensive hydration and nutrition. Such products have a fairly dense structure, and their use helps prevent dehydration. However, when high level Humidity should also not be forgotten about hydration, especially in the summer. But creams with a dense structure are not suitable here. In summer, it is best to use moisturizing gels that quickly penetrate the skin and do not create unnecessary heaviness.

Video about dry air in apartments

Typically, during construction
country houses hydrogeological and relief features are not taken into account
built-up area, unsuccessful foundation design solutions are used,
waterproofing materials are selected incorrectly and, as a result, basements and
ground floors cannot be used due to incoming moisture at discretion
owners. Constant dampness and mold penetrate the load-bearing structures over the years
structures and foundation elements. Droplets of water fall into the narrowest, sometimes
invisible cracks, with the onset of cold weather the water freezes and, expanding, leads
to damage. As a result of moisture penetration into the building structure,
begins to gradually collapse. “Properly performed basement waterproofing
will ensure the durability of the entire building, protecting against the penetration of water and moisture, and
will also improve its performance characteristics,” believes Vladimir BUKIN, head of sales department
Group of companies "Kalmatron".

Basements are not only in old houses, but also
in modern cottages they are subject to waterproofing, especially those with
the construction of which did not have drainage or external waterproofing. IN
In most cases, the appearance of water in the basement is associated with water that
are divided into three main categories - soil, groundwater And
high water “Without protection, concrete will deteriorate quite quickly. You can protect it from moisture in different ways and
materials. The most advanced technologies are offered by Penetron, Kalmatron,
"Hydrotex" and "Prism" (impregnation for concrete "Monolit-20M"). "Roofing felt, bitumen -
It’s not even yesterday, but the day before yesterday. The most profitable, in our opinion
look, material for waterproofing in Western Siberia— this is the impregnation of the “Monolit-20M” series.
It is easy to apply, has no pungent odor, penetrates deeply (up to 5 cm) into concrete and
reliably waterproofs it. One application from the outside or
inside foundation. Cost of 1 sq. m of waterproofing
is about 20 rubles,” explained Yuri PUZYRNIKOV, Director of Prizma LLC.

Where
is there water coming in?

Before you start waterproofing
basement, you need to figure out where the water is coming from into the basement. "Most
probable places water penetration into the basement may be “cold”
seams" if the foundation was made in a monolithic manner with a large temporary
interval, between pours and between poured layers there are soil particles
or debris that prevent adhesion (adhesion) concrete layers. Also
Interblock seams may also be insufficiently protected if the foundation
made of blocks, and places where communications enter the basement. In addition to this, in
concrete contains pores, capillaries and microcracks through which
the possibility of through filtration of water into the basement,” added Vladimir BUKIN. When inspecting the basement
Before waterproofing, you should mark all leakage points and be especially careful
perform waterproofing in them. Having determined the places of leaks,
The problem of choosing a waterproofing material arises.

Basement waterproofing work in
old building structures should be carried out together with the removal of salts
and bioflora from all surfaces. Even if groundwater does not rise to
level of the basement floor, capillary
waterproofing. When the cause of flooding is high water or groundwater
water, the water level may rise above the basement floor. To combat this
Due to this phenomenon, drainage systems are built on the site. As explained Vladimir BUKIN, "horizontal tubular drainage used in
cottage construction, can be of a perfect and imperfect form - then
there is one that cuts through the aquifer completely and cuts through it only partially.
The drainage is cut-off in shape (it intercepts the flow of groundwater from the top
sides of the building and from the sides) or circular (borders the building on all sides).
Last option more reliable and therefore preferable.”

Water penetration problem is often
remains despite design changes basements (attempts to raise the floor to
15-20 cm, fill the basement completely with soil and other similar solutions). Sun? This
does not lead to the desired result - the basement walls may not dry even in
hot season due to constantly seeping water. The situation is sometimes not
water reduction also saves - creating drainage: the groundwater level can
be higher than the base of the foundation, and then water can flood the drainage
system, and the pumps will not be able to pump out water. Thus, even
creating an expensive drainage system, it is also necessary to carry out work with
using high-quality waterproofing materials.

Protection of the underground part of the building
provides complex system waterproofing foundations and other underground
parts of buildings and structures, which include different kinds horizontal and
vertical waterproofing, as well as drainage.

Types of waterproofing

Horizontal waterproofing
foundations are usually made from rolled waterproofing materials and
laid on the marks of the bottom of the basement floor, just above the blind area of ​​the house
and in the area where the basement floor adjoins the foundation. Last time
Developers are increasingly using penetrating waterproofing. Fast, inexpensive,
reliable, and, most importantly, allows you to do without the weight of a concrete screed. Vertical
waterproofing is applied to the external and internal surfaces of the foundation. She
can be coating, pasting, penetrating or screen. "For execution
For coating waterproofing, bitumen-polymer mastics and also (less commonly) cement-polymer compositions are used.

Mastics are liquid polymer-bitumen
cold and hot application compositions intended for waterproofing
construction seams, protection and restoration of waterproofing coatings.
Hot mastics acquire waterproofing properties after cooling, and
cold - after drying. Advantages liquid materials- education
seamless enveloping waterproofing film on any surface and
good grip on it. Regular bitumen should not be used for this purpose - as a result of natural aging, it quickly
will become brittle and crack,” comments Vladimir BUKIN.

It must be remembered that in the event
if used coating waterproofing, any mastic should be applied as
in at least two layers, and between the layers of mastic a reinforcing material must be laid
gasket, for example, made of fiberglass or fiberglass mesh.

Penetrating waterproofing is applied to
the inner and outer sides of the foundation. Penetrating waterproofing composition
is a mixture of Portland cement, finely ground quartz or
silicate sand and active chemical elements. When applied to damp
surface active ingredients react with cement components
concrete (mortar) and form insoluble crystalline complexes, tightly
filling pores and cracks throughout the entire volume of the material. "Laboratory
research and application practice have shown that the usual penetration depth
crystals, for example KALMATRON - about 15 cm. Strength characteristics of building
materials increase by 18-20%, water resistance (W) increases
by four steps. Crystalline neoplasms, not allowing water to pass through, at the same time
time do not interfere with the movement of air, allowing the concrete to “breathe”. designs,
treated with such waterproofing, resist the effects of most
aggressive environments, preventing corrosion and penetration of unwanted chemicals
V environment. The material is inert, does not contain solvents and does not emit
fumes. The service life of the material is equal to the life of the concrete itself. Processed
similar material concrete structures: resistant to aggressive environments, have
better strength characteristics, more frost-resistant, no drying required
surface, no surface leveling required
protection during backfilling and placement of metal reinforcement, not dangerous
punctures, tears or separation from the surface are waterproof. Waterproofing
KALMATRON materials not only provide a long service life, but also
significantly reduce the cost of hydro insulation works", explained Vladimir BUKIN. In progress
during basement construction, waterproofing is carried out with outside foundation.
Basements in old buildings are insulated from the inside.

Screen waterproofing is used in
conditions close to extreme, for example, under the pressure influence of soil
water It is made in the form of a clay castle, the role of which can be played by special
bentonite clay panels or special geotextile membranes. At
device adhesive waterproofing rolled materials glued to external
foundation surfaces - by fusing (submelting) with burner flames
or using a special adhesive mastic. If the material fits
by melting, the base should be primed with a primer before laying.

“Also for “treating” old basements
technologies for injecting compositions on mineral minerals may be proposed
base, polyurethane, epoxy and other bases. But when it's destructive
the effect of groundwater, technogenic and surface water on the walls is quite large,
many of the injection materials mentioned above are ineffective
due to insufficient elasticity, poor adhesion to wet surfaces,
inability to bridge internal kinks, - believes Vladimir BUKIN. — There are also methacrylate gels that are quite effective,
but the cost of such waterproofing is often around 6 thousand rubles / sq. m. They
popular in the West, especially in Holland, where a third of the country's territory
is below sea level and the use of methacrylates is more
preferable in conditions of high moisture pressure compared to others
injection waterproofing compounds, such as polyurethanes and epoxy
resins."

Technology
waterproofing basements

As practice shows, the majority
errors leading to damage to the waterproofing layer are allowed precisely on
preparatory stage. A significant number of buildings in Russia suffer from problems
zero cycle, where lack of attention or unprofessional choice of materials
and technologies lead to the emergence of indoor high humidity, What
poses an immediate threat to both health and the integrity of the structure.
Errors encountered when performing insulation work are especially dangerous because
that the work to eliminate them in compliance with all construction rules costs
not cheap, and all subsequent improvements and alterations do not always provide
obtaining waterproofing of appropriate quality.

With all the variety of waterproofing
materials, almost all of them are used on the water pressure side, outside,
when groundwater puts pressure on the waterproofing layer that protects the walls
foundation. Penetrating waterproofing allows waterproofing
work from inside the premises. " Internal waterproofing basements apply if
the construction of the facility was carried out without taking into account the impact of ground and surface
water, the external waterproofing of the basement is damaged or completely missing, and its
repairs cannot be carried out due to extremely high excavation costs
outer wall foundation or other objectively existing reasons,” noted Vladimir BUKIN.

Penetrating
waterproofing

Penetrating waterproofing was
developed yet? in the 40s of the last century by VANDEX. It is based on the effect
capillary conductivity of concrete. Penetrating materials are classified into two types −
applied with a brush and applied with a spatula or spray gun.

"The principle of action of chemically active
substances are the same. The result of quality work will also be
is the same. But with not very high quality.... For example, when using
With KALMATON you, in addition to penetrating into concrete, get an additional layer
1.5-2 mm from the same. This hard layer is completely fused with
concrete. You can see it by eye: no cracks, no chips, no bubbles - that means it’s grown together
and penetrated. Is it so easy to guarantee the continuity of the coating and
continuity of penetration with the brush method of application? It looks like something
is on the surface (I mean stains of material), but has it penetrated, have the builders prepared it well?
concrete surface and have the pores opened? This is not a fact. Traces of material may
may be, but there may not be a guaranteed continuous carpet. From this conclusion
suggests itself - surface preparation for brush penetrating materials
- this is not just important, but extremely important! At the same time, it is also necessary to keep in mind that
brush materials should be used with extreme caution on old concrete, where
as experts know, there is no free lime, i.e., a medium for germination
crystals. But “spatula” penetrating materials, for example KALMATRON,
They are not afraid of this, since they themselves carry a nutrient medium. At the same time, if
However, you have damaged this layer by 1.5-2 mm, the waterproofing will still work, so
how it “sits” in the very pores of the concrete,”
added Vladimir BUKIN.

General condition for working with penetrating
materials - the temperature of the concrete and the temperature in the room itself should not be
lower than +5 °C. The first stage is preparatory. Chemically active components
must penetrate into the body of the concrete, so the concrete must be cleared of cement
“milk” (its pores are opened), bioflora, various organic contaminants.
It is necessary to remove weak fragments, any cement dust that is in
may further negatively affect the adhesion of the material to the concrete
surfaces. Saturate the concrete generously with water. Chemicals penetrate into the body of concrete through
water, how deep the water will penetrate, to the same depth in the pores of concrete
Crystals will grow that will not allow water to pass through. The second stage is working with seams,
junctions, cracks, cavities and sinks. Please note:
“cold” seams, places where the old and new fills border in a monolithic wall.
Since seams are always the most susceptible to leaking, they receive special attention.
attention when working with penetrating materials. The third stage - waterproofing
concrete surface. The fourth stage is caring for the waterproofing layer,
keeping it moist for three days.

“If work takes place in the open
air, when there is active evaporation of moisture from concrete, it is necessary to organize
covering works. If required by the situation, then protection should also be provided
from capillary ground moisture (even if the groundwater is below
basement), for which horizontal cut-off of capillary moisture is carried out using the
injection (for example KALMATRON-D). With this method it is possible
plug capillaries for effective waterproofing of basements. If all
associated factors are taken into account if settlement of the foundation walls has already occurred and
no further progress is expected, penetrating waterproofing is a good chance
solve the problem from inside the room, without digging up the foundation, especially since it is not
limits the time of work to a certain season. You can spend
waterproofing works even in winter. Especially if you know what happened to the old one
you have problems with isolation - don’t wait for spring or autumn, when there’s an emergency
it will be necessary to eliminate both the leaks themselves and their consequences,” noted Vladimir BUKIN.

Service life of penetrating waterproofing
is equal to the life of the entire foundation, and there is no need to repair it. At
In this case, the walls remain vapor permeable. “This year we are launching production
dry mixtures based on HYDROCONCRETE SRG-2, SRG-1 and KALIMATRONA-EKONOMA with microfiber. What will add to the finished product?
even more strength, crack resistance and even water resistance. Repair data
compositions will be very relevant at sites where concrete elements have lost their
bearing capacity and close to natural wear. We use “pilot” already in
some regions, now we will launch production in our city
Novosibirsk,” comments Vladimir
BUKIN.

Trends
market

Russian waterproofing market
materials is characterized by a significant variety of domestic products
and foreign production. “The main part of the market belongs to traditional
bitumen-polymer materials - bitumen and roofing felt, which have the lowest
price, and therefore are used more often than others in construction. Many specialists
note that bitumen will not soon be replaced by innovative materials, -
added Vladimir BUKIN. - Market
today offers a huge number of both our Russian and imported
waterproofing materials. If they are not selected correctly, the problem will not be solved.
It will either succeed at all, or you can achieve a short-term effect. Trying
protect the walls of your basement with various waterproofing compounds from the inside
without consulting specialists, you can waste a lot of money and
nerves".

Among the manufacturers of penetrating
waterproofing experts highlight the following companies: Kalmatron, Schomburg (Akvafin),
“Lakhta”, “Xipex”, “Stromix”, “Penetron”, etc. Moreover, the share is precisely
domestic waterproofing exceeds the share of imported ones. At the same time almost
half of the market players produce penetrating waterproofing. By by and large,
here everything is determined by the habit of the developer. Bitumen-polymer materials
occupy a large market share, although the emergence of new technologies still pushes consumers
towards innovation. “If the economic situation is favorable, the market for this
products will grow and grow. There is still a long way to go before saturation. We're so decent
residential and industrial infrastructure was “destroyed” in the 90s, what to repair?
and we will be restoring for a long time,” concluded Vladimir BUKIN.

“It is worth noting that both customers and
clients are becoming more demanding, more informed, and this,
certainly has a very positive effect on the market building materials V
in general. The market for waterproofing materials will expand, it is far from
saturation,” comments Elena
BAGUTO, Development Director, Trading House "Stroyding", official dealer of CJSC "GC "Penetron-Russia" on
territory of the Novosibirsk region.

Evaporation of moisture from water surfaces in indoor water parks.

CEO

"Stroyinzhenerservice"

Chief Specialist

"Stroyinzhenerservice"

Professor of the VITU department

doc. tech. sciences

In indoor water parks, various pools and water attractions are the main sources of significant moisture inputs, which must be taken into account when designing their ventilation and air conditioning systems. Insufficient accounting of moisture inputs from these sources can lead to the constant occurrence of moisture condensation from the air during the operation of indoor water parks. internal surfaces various building structures and non-compliance with the permissible temperature and humidity conditions of the air environment in the area where swimmers stay. Our experience in designing ventilation and air conditioning systems for indoor water parks has shown that a thorough analysis is required to assess their moisture inputs:

– technological modes of use of swimming pools and water attractions;

In this regard, it should be noted that the greatest difficulties arose with the establishment (reasonable choice) of calculated dependencies for determining moisture inputs from water surfaces.

Currently, there are many formulas recommended for estimating moisture evaporation, which are based on the results of laboratory experiments. Doubts have arisen that laboratory experiments take into account the full extent of the conditions under which moisture evaporates from the water surfaces of pools and attractions in indoor water parks. Therefore, it was decided to analyze the calculated dependencies to determine the intensity of moisture evaporation from water surfaces, recommended by various regulatory documents existing in domestic and foreign practice. During the analysis, special attention was paid to the conditions of obtaining and possible areas application of recommended calculated dependencies for assessing evaporation from water surfaces.

In domestic practice To calculate the amount of moisture evaporating from an open water surface, the dependence proposed by the drying laboratory of the All-Union Thermal Engineering Institute (Moscow), which is based on the results of extensive experiments conducted under the following conditions, has been widely used:

– air temperature – t=40÷225 0С;

– air speed – υ=1÷7.5 m/s.

In the experiments, evaporation conditions close to the adiabatic process were provided. The dependence developed in this case was included in the “Instructions for the design of heating and ventilation” (SN 7-57), and then in the “Designer’s Handbook. Ventilation and air conditioning” book. 1, ed. 1992 (SPV) as follows:

G=7.4(аt+0.017∙υ)∙(Pн-Рв)∙∙F, (1)

where G is the amount of evaporating moisture from an open water surface with area F (m2), kg/h;

υ – relative speed of air movement over the water surface, m/s. For swimming pool halls, according to SNiP 2.08.02-89*, no more than 0.2 m/s can be recommended;

аt – coefficient depending on the water temperature in the pool (0.022÷0.028 at twater=28-40 0С);

Pv – partial pressure of water vapor in the air of the working area of ​​the room, kPa;

Pн – pressure of saturated water vapor in air at a temperature equal to the temperature of water, kPa;

As noted by Prof. in the book “Ventilation, Humidification and Heating in Textile Factories” (ed. 1953), formula (1) is a modified Dalton formula, which has the following form:

G= , (2)

where C is the evaporation coefficient (0.86 – with strong air movement; 0.71 – with moderate air movement; 0.55 – with calm air).

This dependence was obtained by Dalton as a result of his numerous experiments on the evaporation of water, which was heated in round bowls ø8.25 and ø15.24 cm on braziers to different temperatures. At the same time, in the experiments, the speed of air movement above the evaporation surface varied arbitrarily. Therefore, Dalton’s formula does not indicate quantitative characteristics of the speed of air movement above the evaporation surface. In the book “Ventilation” (ed. 1959) prof. An estimate of the possible speeds of air movement in Dalton's experiments is given:

– with strong air movement, the air speed could be 1.57 m/s;

– with moderate air movement - 1.13 m/s;

– in calm air conditions - 0.58 m/s.

Based on these data, the value of the evaporation coefficient C = 0.4 was established at an air velocity above the evaporation surface of 0.2 m/s.

In foreign practice To calculate the evaporated moisture from the water surface of swimming pools, the formulas given in the Dantherm Design Guide are used, which make it possible to take into account the influence of the occupancy of the pool by swimmers and their activity on the evaporation of moisture. The Guide notes that in Germany the formula of the VDI 2086 standard developed by the Society of German Engineers is used to calculate the evaporation of water from the water surface of indoor swimming pools:

G=ε∙F ∙(Pn-Rv)∙10-3 , (3)

where ε is the empirical coefficient of water evaporation from the water surface of the pool, g/m2∙h∙mbar, depending on the mobility of the water surface, the number of swimmers and their activity.

e=35 – for pools with slides and significant wave formation;

e=28 – with average mobility of the water surface for public swimming pools and normal activity of swimmers (pools for recreation and entertainment);

e=13 – with a low-moving water surface for small swimming pools with a limited number of swimmers;

e=5.0 – for still water in swimming pools;

e=0.5 – closed water surface in swimming pools.

It should be noted that formula (3) is also a modification of Dalton’s formula, and its empirical coefficient e reflects the influence on the process of moisture evaporation of both the speed of movement of the water surface and the speed of air movement due to the relative speed of movement of these media.

In the UK, to calculate the amount of moisture evaporating from the water surface of swimming pools, as noted in the Dantherm Design Guide, the Byazin-Krumme formulas are more often used, which are established on the basis of field measurements of the intensity of moisture evaporation carried out in existing swimming pools. For the daytime period (the period of use of the pool), the Byazin-Krumme formula is recommended in the following form:

G= ∙F , (4)

where A is the pool occupancy factor for swimmers, depending on the number of swimmers n (people) and the area of ​​the pool F (m2);

DP is the difference between the water vapor pressure of saturated air at the water temperature in the pool and the partial pressure of water vapor in the pool air, mbar.

For the night period (during the period of inactivity of the pool), the recommended Byazin-Krumme formula is:

G= [-0.059+0.0105∙]∙F (5)

We carried out calculations of the intensity of moisture evaporation from the water surface of swimming pools during the period of their use (in daytime) according to formulas (1÷4). At the same time, three types of pools and water attractions were considered depending on the temperature of the water used:

type 1 – general pools of water attractions, twater=30 0С;

type 2 – children's pools, twater=35 0С;

type 3 – Jacuzzi pools, twater=40 0С.

The following were taken as initial data in calculating the rate of moisture evaporation when using swimming pools:

Рн – pressure of saturated water vapor in the air at the water temperature in the pools (for pools of type 1 - 37.8 mbar; type 2 - 42.4 mbar; type 3 - 73.7 mbar);

Рв – partial water vapor at acceptable parameters air for all types of pools. In the warm period of the year Рв=25.4 mbar (tadd=30 0С and jadd=60%), in cold period year Рв=20.1 mbar (tadd=29 0С and jadd=50%).

Thus, the calculated values ​​DP=(Рн-Рв) for various types pools are for pools of type 1 from 12 to 18 mbar; 2 types - from 18 to 23 mbar; 3 types - from 48 to 54 mbar.

When calculating the intensity of moisture evaporation, the following were taken:

– in formula (1) the average value of the coefficient аt=0.025 at air speeds υ=0.2; 0.9; 1.5 m/s and Pbar=101.3 kPa;

– in formula (2) air speed υ=0.2; 0.9; 1.5 m/s, and the value of Pbar = 760 mm. rt. Art.;

– in formula (3) the values ​​of the coefficient e=35; 28 and 19;

– in formula (4) the values ​​of pool occupancy by swimmers: A=0.5; 1.0.

The results of calculations of the intensity of moisture evaporation from water surfaces using formulas (1÷4) are presented in the graphs in Fig. 1, a comparison of which allows us to note the following.

The results of calculations of moisture evaporation from the water surface using the formulas of the VDI standard (at e=35; 28 and 19) and SPV (at air speed over the water surface υ=1.5; 0.9 and 0.2 m/s) coincide with the results calculations using Dalton's formula (at air speeds υ=1.5, 0.9 and 0.2 m/s). This indicates that these formulas were obtained based on the results of laboratory experiments similar to Dalton’s experiments. These laboratory experiments are characterized by the following conditions:

– a calm, smooth (without wave formation) water surface of evaporation, above which, when air moves, there is always an indestructible boundary layer of air with the pressure of saturated water vapor at the temperature of the water surface;

– the temperature of the water surface is several degrees lower than the temperature of the bulk of the water, i.e., the process of heat and mass transfer between the water surface and the air moving above it “tends” to an adiabatic process.

The area of ​​results for calculating the intensity of moisture evaporation from the water surface using the Byazin-Krumme formula (at values ​​of the swimming pool occupancy factor A from 0.5 to 1.0) “lies” below the area of ​​results for the intensity of moisture evaporation established using the Dalton, SPV and VDI standard formulas . This indicates the presence of fundamental differences in the process of heat and mass transfer between the water surface and air environment operating pools from the process of heat and mass transfer when conducting experiments in laboratory conditions. These fundamental differences in the process of heat and mass transfer in operating swimming pools and water attractions include:

– constant destruction of the water surface (formation of waves, splashes and drops), the intensity of which depends on the occupancy of the pools by swimmers and their activity;

– constant destruction of the boundary layer of air above the water surface with the pressure of saturated water vapor at a temperature equal to the temperature of the water in the pool, which is established as a result of its mixing by swimmers. Therefore, the process of heat and mass transfer between the water surface and the air moving above it in this case does not “tend” to an adiabatic process, but is essentially some kind of polytropic process, “directed” at the temperature of the water established throughout its entire mass in the pool.

The results of calculations of the intensity of moisture evaporation, obtained using the formulas of Dalton, SPV and the VDI standard at an air speed of υ = 0.2 m/s, intersect the range of results of calculations of the intensity of moisture evaporation, obtained using the Byazin-Krumme formula with values ​​of the pool occupancy coefficient for swimmers A from 0.5 to 1.0. The nature of the intersection of these results emphasizes the above-mentioned fundamental difference between the conditions of moisture evaporation during laboratory experiments and the conditions of moisture evaporation in operating pools.

The above allows us to conclude that the most objective data on the intensity of moisture evaporation from the water surfaces of swimming pools and water park attractions during the period of their use can be obtained by assessing them using the Byazin-Krumme formula (formula 4). In this case, it is necessary to take the values ​​of pool occupancy by swimmers A, based on existing standards their use. In accordance with the Dantherm Design Guide, the swimming pool occupancy values ​​A are determined by the formula:

where 6.0 is the standard value of the pool area per bather (m2/person) with occupancy factor A=1.

For most public swimming pools, it is recommended to take the value of the pool occupancy factor A = 0.5 as the calculated value.

We calculated the intensity of moisture evaporation from the water surface of the pools during the period of inactivity (at night) using formulas (1÷3 and 5). In this case, the initial data were taken to be the same as for the period of use of the pools. In this case, when calculating the intensity of moisture evaporation, the following were taken:

– in formula (1) air speed υ=0;

– in formula (2) at air speed υ=0 evaporation coefficient C=0.3;

– in formula (3) the value of the evaporation coefficient is e=5.0.

The results of calculations of the intensity of moisture evaporation from the water surface using formulas (1÷3 and 5) are presented in the graphs in Fig. 2, a comparison of which allows us to note the following.

The results of calculating the intensity of moisture evaporation from the water surface using the Dalton and SPV formulas significantly exceed the results of calculating the intensity of moisture evaporation from the water surfaces of pools using the formulas of the VDI standard and Byazin-Krumme. This circumstance can be explained by the fact that the formulas of the VDI and Byazin-Krumme standard more strictly take into account the real temperature and humidity conditions of interaction of air with the surface of the water during the period of inactivity of the pools, while the Dalton and SPV formulas, based on the results of laboratory experiments, do not reflect these conditions. Therefore, to calculate the intensity of moisture evaporation from the water surfaces of pools during periods of inactivity, preference should be given to the latest formulas and, above all, the Byazin-Krumme formula.

1. For indoor water parks, the dependencies of the Designer’s Handbook cannot be recommended. Ventilation and Air Conditioning" to determine the intensity of moisture evaporation from water surfaces, based on the results of experiments that do not take into account the operating conditions of existing swimming pools and water attractions.

2. When designing ventilation and air conditioning systems for indoor water parks, to determine moisture inputs from the water surfaces of pools and water attractions (during their use and inactivity), it is advisable to use the Byazin-Krumme formulas, as they most fully reflect the processes of moisture evaporation in operating pools.