TÜRCERT engineers, which serve in the context of ventilation project, guarantee to improve your infrastructure and make your ventilation projects with the best result. For ventilation projects, let us first know the ventilation systems.
Single Channel System
Single channel feeding system arrangement; transports the air to a certain number of zones. The single-channel system provides feed to all regions to provide the required low air temperature. The temperature of each zone is controlled by means of a room thermostat in the zones and a heater in the arm separation. The smallest amount of ventilation required is made by adjusting the outside air absorbers to a minimum. In extreme cold and extremely hot weather, the external air dampers are set to the lowest value, but in warm weather they may be open.
Dual Channel System
Double-channel feeding systems, two hot-cold air to each region of the two arms goes. The desired room temperature in the area
To adjust a mixture in the room are mixed in hot and cold proportions.
Return and Exhaust Systems
In the return and exhaust system, instead of the lever exits in a supply circuit, it can be characterized by a greater number of handgrip entries. The return air portion of an air conditioning channel circuit and the exhaust duct circuit of a factory are typical examples of such systems.
Air is divided into three according to the forces that provide motion:
Natural ventilation: The movement of the air and therefore the renewal depends on the temperature differences and the wind effect. (Chimney and wind effect)
Natural-mechanical ventilation: Wind-driven flue extractors are examples.
Mechanical Ventilation: In this type of ventilation, air is supplied by a fan,
Buddha 3 can be in the form;
Natural outlet with mechanical inlet (with ventilator)
Natural inlet mechanical outlet (aspirator)
Mechanical inlet and outlet (with fan and aspirator)
Number of Change and Renewal of Ventilation Coefficients
Stables 8-15
Operating rooms 6
Analysis Lab 7-8
Bathrooms 6-10
Printing Centers 10-15
Waiting Rooms 7-8
Great Shops 7-8
Warehouses 5-10
Recreation Rooms 7-8
10 Joiners
Shower Areas 15-20
Shower Enclosures 15-20
Shops 6-15
Steakhouses 20-30
Home Toilets 10-15
Photocopiers 12
Furnaces (melting and heat treatment furnaces) 30-60
Galvanic Bathrooms 25
Night Clubs 18
Dressing Rooms 8-12
Business Locations 12
Body shops 20-40
Cellar 10
Clinics 5
Conference Rooms 10
Hairdressers 10-15
Dry Cleaners 30-40
Libraries 5
Carpenters 10
Medical Offices 2-4
Motels 10-15
Museums 5
Offices 6-7
Schools 5-7
Living Rooms 3-6
Pet Shops 15-30
Pizzeria 20-40
Pubs 8-14
Restaurants 8-15
Restaurant Kitchens 25-35
Self Service 10-20
Greenhouses 4-10
Sporting Goods 8-15
Super Market Stores 5-10
Tanneries 10
Repair shops 15-30
Theaters 6-8
Public Toilets 10-15
Veterinary Clinics 10
Dormitories 5
Bedrooms 2-4
Underground Laundries 30-40
Paint shops 30-60
Machining workshops 6-10
Banks 2-4
Hotel bars 4-6
Laundries 20-30
Bakery ovens 20-30
Offices (*) 4-6
Cafeteria and cafeteria bars 10-12
Cargo holds (in general)
In food such as meat, eggs, etc. 6-10
Containers 10-20
Canteens 4-6
Dark rooms in photo studios 10-15
Mushrooms (mushroom grown spaces) 10-20
Movie theaters (*) 10-15
Commercial kitchens or school kitchens 15-20
Home kitchens 10-15
Factories (in general) 6-10
Foundries 20-30
Fruit storage vessels 20-30
Garages (car repair and repair) 6-8
Meeting rooms (*) 4-6
Hospitals 4-6
Laboratories 4-6
Washbasins 10-15
Swimming pools 20-30
XINUMX 6
Residential areas 1-2
Restaurants 6-10
Pool hall 6-8
Boilers 20-30
Classes 2-3
Club halls 8-10
Dance halls (*) 6-8
Machine rooms 20-30
Recreation in salons 10-20
Paint shops 20-30
Theaters (*) 10-15
(*) In case of smoking inside the spaces with the sign, it is seen that the number of air regeneration or change at the time indicated in the table should be doubled.
For example ;
Assuming the height of a factory with 10 meters length 5 meters as 4 meters
10 x 5 = 50 m²
50 x 4 = 200 If the average 6 air exchange is taken as the number of air changes 10-8 in m³,
200 x 8 = 1600 is calculated in m³ / h.
Section 1. Development of Design Strategy
1. Meeting System Requirements:
In the design of the Natural Ventilation System, two important factors affecting environmental performance are taken into account.
Ventilation to maintain adequate indoor air quality,
In addition to other systems, ventilation reduces the tendency of the building to overheating, especially in summer.
The natural ventilation strategy should also be considered when designing other systems. Natural ventilation should be taken into account when building design. Factors to consider:
Adequate acoustical environment: Natural ventilation openings increase the sound penetration from the outside. This may be a decisive factor depending on the location of the building. In addition, buildings with natural ventilation contain excess bare concrete to increase the thermal capacity of the site. Large areas of this type should be carefully designed to ensure proper acoustic environment
Smoke Control: The fire safety system should be able to work integrated with the natural ventilation system, as smoke can follow the natural ventilation paths.
Health and Safety: Most natural ventilation openings will be positioned higher than the base plane. In this way, the rules of working at height shall be taken into consideration in detail.
1.1. Ventilation:
The main purpose of the ventilation is to keep the air quality at a certain level by removing the airborne pollutants in the middle or by reducing their effects.
Orientation is provided in Approved Document F to ensure the required indoor air quality. It is possible to do the ventilation above the ratios. But these high values will change the perception of freshness and show itself as an increase in energy expenditure. Approved Document F contains three strategies for adequate indoor air quality:
(a) Exiting Ventilation: In order to dispose of pollutants, the internal air is expelled and replaced by external air.
(b) Whole Building Ventilation (Feeding and ejecting): Provides distribution of other pollutants and reduction of their effects
(c) Purge ventilation: Elimination of high concentrations of pollutants. This high concentration may be, for example, by a dye modification or by accident release of fuel into the environment. Cleaning ventilation is slightly stronger than the background ventilation. In addition to reducing the amount of high pollutants, it also helps to remove excess heat from the environment. It facilitates the formation of thermal comfort in the summer months.
Example Natural Ventilation Application The recommended quantity for all building ventilation is 10lt / sec (in CİBSE Guide A and Approved Document F). This amount was determined by considering the correlation between the amount of ventilation and health. Since buildings with natural ventilation do not provide a fixed ventilation value, it should be shown that equal air quality is ensured. To demonstrate this, it should be shown that the indoor air quality provided by the natural ventilation is the same as the indoor air quality provided by the fixed ventilation of the 10lt / sec person. When this calculation and measurement is done, the times when the building is full should be considered. A similar calculation can be made for variable ventilation, which is similar to natural ventilation. In both cases, the limit values for the external CO2 concentration and the occupancy rate of the building must be equal. In addition, the maximum concentration obtained in natural ventilation should not exceed the maximum equal value. The indoor air quality (IAQ) tool is enclosed to illustrate how these calculations are to be performed. The figure is shown in 2.
1.1.1. Ventilation Control
If natural ventilation is to be applied to a system, the system must allow a level controllable ventilation, provided that the system is within a certain range. This range can vary from 0,5 (Air Change per Hour) to 5 times per hour. It should also be possible to close the ventilation completely when the building is empty. The main reason for air pollution, especially for people, may not be ventilated while the building is empty.
In addition to satisfying the required amount of ventilation, it should be designed to prevent disturbances which may occur due to drafts, especially in winter. In order to prevent this situation especially in offices, air inlet vents should be located at the top of the floor above 1,7m.
1.2. Control of Overheating in Summer:
The extreme temperature during the summer months is the most important factor affecting the feasibility of natural ventilation. The cooling potential of natural ventilation varies depending on prevailing seasons conditions and the thermal comfort condition of people in the building.
Predictably, natural ventilation systems can meet heat loads up to 30-40 W / m². If the climate change reaches significant levels, this estimate should be taken down. Adaptation of people to climate change can make this value unchanged. In order to achieve generally acceptable summer conditions, three main elements in design and operation are considered:
a. Good solar heat gain is prevented by making good solar control.
b. Internal earnings should be brought to reasonable levels. (human, devices, lighting)
c. During the hottest summer months, the indoor air temperature may exceed 25ºC.
However, in a well-designed building, this can be tolerated with the help of improved air movement and cooler mean radiant temperatures.
1.2.1. Sunlight control:
Next CIBSE TM³7: The improved solar control design will provide detailed information and guidance on solar control performance. Some measures may be taken to reduce overheating to a certain level.
Window size and direction: This factor is related to the overall organization of the building. Shading of windows by surrounding buildings or shading by other parts of the building can reduce solar gain.
Painting, film and coatings (for windows) As a result of new developments in glass technology, solar gain has been reduced with special coatings that do not affect the vision but only pass through specific wavelengths.
Venetian blinds: inside, intermediate or outside
Protrusions, side wings, shutters: This type of solar controls are direction dependent and may require different control types on each side. It also affects the aesthetics of the building.
The performance of these different systems (individually or together) can be counted with the number of effective total solar energy transmission or effective g-value. This value is calculated by the portion of the total solar heat gain passing through the window and shading element in the hottest time by the portion of the solar gain passing through an opening in the same conditions.
In addition to the possible effects of global warming, other effects can also lead to high internal temperatures. These effects should also be considered when designing natural ventilation. The most important effect is the heat room effect of the city with the growth of two cities. This raises the night temperatures in particular. As a result, pre-cooling of the building will be difficult with night ventilation. Detailed information on the heat chamber effect is given in CIBSE Guide A.
1.2.2. control of internal loads:
There are three important loads.
a. Load from people
b. Lighting load
c. Loads from devices.
1.2.3. Comfort Expectations Example of Natural Ventilation
What is important when evaluating overheating is to determine acceptable thermal comfort conditions. Thermal comfort; it differs with a combination of psychology and culture. Adoption comfort conditions vary depending on the activity at the interior, contact points, temperatures, air velocities and humidity.
In buildings with natural ventilation, a more variable air temperature is obtained compared to buildings with normal ventilation. But this does not mean that less comfort is achieved. In summer, air movement can be increased by means of large openings and changes in comfort perception can be made. However, excessive drafts must be avoided during this application. As seen in Figure 2, the 0.25 m / s air flow provides an 1K reduction in dry bulb temperature. These air velocities can only be applied in summer, but are a striking example of the effects of natural ventilation.
Night ventilation can be done to increase the cooling benefit. This application is based on the principle of providing pre-cooling of the building and lowering the average radiation temperature using the advantage of relatively low outdoor temperatures at night. By decreasing the average radiant temperature, comfort conditions are provided even if the air temperature increases in the area. By increasing the thermal capacity, the amount of heat that the building can store due to the increase in the average radiative temperature of each degree is increased, thus increasing the capacity of the site to provide thermal comfort conditions. The advantage of the thermal mass is shown in Figure 3. This figure shows the effect of thermal mass and night ventilation on the internal temperature. A building with a mild thermal mass without night ventilation and two night-ventilated buildings with high thermal masses can exhibit temperature differences up to 5K.
1.3. Acoustic Performance http://www.tesisat.com.tr/dokumanlar/100/TARSU_3.jpg
The presence of distinct external sources of sound is the most difficult factor in the implementation of natural ventilation. There are two main solutions to this problem:
Ventilation vents are made to the side away from the sound source. If the sound source is traffic, the opening of these openings to the non-traffic side also ensures that the natural air is clean.
Acoustic curtains can be added to the ventilation openings. Especially for schools, it is very important to have good acoustic performance with natural ventilation. BB93 offers recommendations for the combination of acoustic performance and natural ventilation. Fig. 4 shows that the acoustically-protected ventilation opening can be integrated with the window edge and environmental heating.
1.4. Natural Ventilation and Hybrid Mode
The above described the conditions for the application of natural ventilation in a building. In addition, all areas of a building must not be ventilated with the same system. Different sections, different strategies, can be applied at different times. This is called a mixed mode approach. CIBSE is described in detail in AM13. Several approaches for mixed mode are listed below.
a) Conditional Mixed Mode:
(Contingency mixed-mode)
This system is used if flexibility is needed in the neighborhood. In such systems, design should be done considering the cooling load which may increase depending on climate change or the tenant's wishes. The prediction to be made here should also include the gaps to be left on the floor and the ceiling for the installation of additional systems. The cost of additional flexibility should be compared and decided by the cost of operation and installation that will be caused by unnecessary air conditioning.
b) Regional Mixed Mode:
(Zoned mixed-mode)
This mode is taken into account for the different uses of different parts of the building. Air conditioning is applied where there is a real need. In places with low heat gain, heating and ventilation are done. This type of approach is applied to the areas where it is expected to have constant heat loss and gain during the life of the building. Such applications can create tension between users. Users of two sites with different conditions may think that the other is in better conditions and search for the right.
c) Recurrent Mixed Mode:
(Changeover mixed mode)
This mode considers that the cooling load of each space may vary between seasons. An example of this is mechanical ventilation which is used in extreme weather conditions (extreme heat or extreme cold). In warm weather natural ventilation is used. This usage eliminates the effect of drafts in winter. It also helps to pre-cool the building with night ventilation.
d) Simultaneous Mixed Mode:
(Concurrent mixed-mode)
Mechanical and Natural Ventilation provides simultaneous operation. While the mechanical system meets the need for fresh air, opening windows or openings help to cool down for summer. In addition, mechanical ventilation can be opened for night cooling and the safety shortage in natural ventilation can be eliminated. Excessive hot air in the extra natural ventilation will provide unnecessary fresh air can lead to energy wastage.
Figure 5 includes a surface flow diagram for users to be used in the selection phase.
1.5. Getting Started with Design:
If it is concluded that natural ventilation can be applied after the above mentioned, it is decided whether it is a uniform or mixed system. The next strategy goes into the design concept. 3 significant step takes place during the design phase.
a) Modeling of air flow from the entrances to the exits:
This model depends on the shape and organization of the building. In addition, the purpose of the building and the location of the building and the ventilation is also effective. For example, if there is an overly busy road on one side of the building, it would be pointless to make air inlets from that direction. In terms of pollution and air quality, air intakes should be placed in the other direction.
b) The main driving forces to be examined for the Desired Air Flow Model:
Many strategies take into account wind pressures while others take advantage of the temperature difference. In some cases a good design that can be used by fans to assist these natural forces is made to ensure that the dominant forces provide the desired flow.
c) Sizing of openings for the desired air flow and flow rate: This takes place in three stages.
1. Flow rates are calculated considering thermal comfort and air quality.
2. The position and size of the openings are calculated to provide these flow rates in design conditions.
3. Control system should be designed for automatic operation of the system in various occupancy rates and weather conditions.
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Section 2. Sample Of Building Tarsu AVM:
1) The shopping center we designed will be built in Tarsus.
AVM total area: 63.180 m²
Parking area: 23 380 m²
Selling areas: 27 750 m²
Total space for natural ventilation: 13.426 m²
Rooftop Unit Used in Atrium Region
Number (with single fan): 4
Fresh air openings for the atrium: 2 m² x 20 Quantity = 40 m² (Total)
Air Ground floor of the building, entering from the South section of the front of the 2 m transition area is opened to the atrium opening the space here, using the gaps, 1. Kata stands out.
1. The openings created in the floor roof ensure that the exhausted air is removed. 1 of the building. There are Foodcourt areas on the Western front and negative air pressure in these areas. Naturally, the air entering the façades is expected to be 2750 in Mall and small shops.
2750 person x 36 m³ / h / person (10 l / s) 100.000 m³ / h needs fresh air.
20 000 m³ / h needs fast food areas, in total 120 000 m³ / h is needed in the worst conditions. This need will be provided by grilles from net entry areas of 40 m². Input speeds accordingly