CALCULATION OF THEIR POWER AND HEATING SURFACE IN IMPROVING THE EFFICIENCY OF AIR HEATING SYSTEMS Текст научной статьи по специальности «Строительство и архитектура»

INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7 UIF-2022: 8.2 | ISSN: 2181-3337

CALCULATION OF THEIR POWER AND HEATING SURFACE IN IMPROVING THE EFFICIENCY OF AIR HEATING SYSTEMS Yorkin Sodikovich Abbasov

Ferghana Polytechnic Institute Ferghana 86 Mavlonbek Alimatjon ugli Usmonov

Ferghana Polytechnic Institute Ferghana 86 https://doi.org/10.5281/zenodo.7315808

Abstract. This article presents the formulas used in the selection of air heaters used in the heating systems of residential and public buildings according to their parameters, their structural structure, capacity, and calculation of the heating surface. In addition, the advantages and disadvantages of heating with heaters are also described.

Keywords: heaters, heat, bladder, density, flow, power, coolant, water, steam, pipe, air flow, air density.

РАСЧЕТ ИХ МОЩНОСТИ И ПОВЕРХНОСТИ НАГРЕВА ПРИ ПОВЫШЕНИИ ЭФФЕКТИВНОСТИ СИСТЕМ ВОЗДУШНОГО ОТОПЛЕНИЯ

Аннотация. В данной статье представлены формулы, применяемые при выборе воздухонагревателей, применяемых в системах отопления жилых и общественных зданий, по их параметрам, конструктивному устройству, мощности, расчету поверхности нагрева. Кроме того, также описаны преимущества и недостатки отопления обогревателями.

Ключевые слова: нагреватели, тепло, камера, плотность, расход, мощность, теплоноситель, вода, пар, труба, расход воздуха, плотность воздуха.

INTRODUCTION

Heaters are devices designed for air heating. According to the type of coolant used, there are the following groups of these devices: water-electric and steam

It is logical to use electrical equipment for rooms whose area does not exceed 100 m2 A more reasonable choice for buildings with large areas are water heaters, which work only when there is a heat source.

MATERIALS AND METHODS

The most popular steam and water heaters, surfaces of the first and second form are divided into 2 subtypes: ribbed and smooth tube. According to the geometry of the ribs, the lamellae and spiral are wound on the ribbed heaters.

The operation of heaters operating on a refrigerant such as steam is regulated by means of special valves installed in the inlet pipe.

By design, these devices can be disposable. If the cooling water in them moves through pipes, it will follow a constant direction and will be multi-pass. There are divisions in their cover, as a result of which the direction of movement is determined. And the cooling water is constantly changing.

Figure 1.

Smooth tube heaters

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During operation, water heaters can withstand large temperature changes. That is: 70-110oC. For this type of heater to work well, the water circulating in the system should be heated to a maximum of 180OC. In the hot season, the heater can also be used as a cooler to cool the rooms of the building.

The smooth tube design consists of heating elements in the form of hollow thin tubes with a diameter of 20 to 32 mm, located at a distance of 0.5 cm from each other. Cooling water circulates through them. The air washing the heated surfaces of the tubes is heated due to convective heat exchange.

Pipes in the air heater are arranged in a checkerboard or corridor pattern. Their ends are welded to the collectors - upper and lower. The coolant enters the distribution box through the inlet pipe, then after passing through the pipes and heating them, it leaves the outlet pipe in the form of condensate or chilled water.

RESULTS

More stable heat transfer is provided by devices that arrange pipes in series, but here the resistance to air flow is higher. To know the real capabilities of the device, it is very important to calculate the power of the device.

Certain requirements are imposed on the air - there should be no fibers, suspended particles, sticky substances. The amount of fixed dust is less than 0.5 mg/m. The inlet temperature should be at least 20OC

Calculation of heater power.

The calculation of the heater is carried out in several stages.

The following are defined in sequence:

Determining the size of the front part, choosing a ready-made device

- Calculation of carrier consumption

- Since the air flow is known from the characteristics of the ventilation system, it is not necessary to calculate it. The formula for determining the heat capacity of the device:

Qm L • Pe • Ce • (tm tHap)

(1)

Qm— heat output of the heater L — air flow (value of supply flow)

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Pe — air density, table value

Ce —SNiP specific heat capacity of air available in the tables (ti — t0) — difference between indoor and outdoor temperature

The indoor temperature is the sanitary norm for a given room, and the outdoor temperature is determined by the average value of the five coldest days of the year for a given area.

We define the front part:

ip

F = T (2)

F — front part. L — air flow. P — air density.

V — a mass flow rate of about 3-5 kg/m2*s is assumed. Then we find the coolant flow rate:

3.6■Qт

G =

(3)

Ce'iPen ^нар)

here:

G - coolant flow rate

3.6 is a correction factor to obtain the required units of measurement Qn - heat capacity of the device Ce -specific heat capacity of the medium

(ti — t0) ) - temperature difference of cooling water at the inlet and outlet of the device Knowing the flow rate of the carrier, it is possible to determine the diameter of the pipes and choose the necessary equipment.

Calculation of the heating surface 1- table

Марка калорифера П р оизводительн ость Площадь поверхности теплообмена, м2 Площадь фронтального сечения, м2 Площадь сечения [среднее значение) для прохода теплоносителя, м2 Число ХОДОВ по теплоносителю, мг Масса, кг

по воздуху, MJ/4 по теплу, кВт

КСк-2-1 2000 24,2 6,7 0,197 0,00056 4 19

КСк-2-2 2500 31,0 8,3 0,244 22

КСк-2-3 3150 39,5 9,9 0,290 25

КСк-2-4 4000 49,8 11,5 0,337 27

КСк-2-5 5000 65,4 14,8 0,430 33

КСк-2-6 2500 32,9 9,0 0,267 0,00076 25

КСк-2-7 3150 42,8 11,2 0,329 28

КСк-2-Э 4000 54,7 13,4 0,392 32

КСк-2-9 5000 68,4 15,6 0,455 35

КСк-2-10 5300 90,0 20,0 0,581 42

КСк-2-11 16000 241,2 58,7 1,660 0,00156 114

КСк-2-12 25000 374,0 88,7 2,488 0,00236 166

The area of the heating surface determines the efficiency of the device. The larger it is the higher the heat transfer coefficient, the stronger the device heats the air flow. It is determined by the following formula:

Q

Fk =

к'(?ср.т ^ср.в)

(4)

Here:

INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7 UIF-2022: 8.2 | ISSN: 2181-3337

Q - heat capacity k - coefficient

tcp.m —average coolant temperature (between the values at the inlet and outlet of the

device)

t

ср.в

— average air temperature (outdoor and indoor).

The obtained data is compared with the passport characteristics of the selected device. Ideally, the difference between the actual and calculated values should be 10-20% more than the actual value.

Pros and cons of heating with a heater.

The home heating system, which is based on the direct delivery of heated air to the specified temperature, is of particular interest to the owners of their houses.

This design of the heating system consists of the following important components:

-a heater that works as a heat generator that warms the air

- channels through which heated air masses enter the house (air ducts)

- a heater that directs well-heated air throughout the entire volume of the room

DISCUSSION

The advantages of this type of system are many. These include high efficiency and the absence of auxiliary elements for heat exchange in the form of radiators, pipes, and the ability to combine it with the climate system and low inertia, as a result of which large volumes are heated very quickly.

CONCLUSION

In the improvement of heating systems of residential and public buildings, it is possible to reduce excess energy consumption as a result of the correct selection of heating equipment and its use taking into account its technical parameters.

REFERENCES

1. Abbasov, Y. S., & ugli Usmonov, M. A. (2022). Design of an Effective Heating System for Residential and Public Buildings. CENTRAL ASIAN JOURNAL OF THEORETICAL & APPLIED SCIENCES, 3(5), 341-346.

2. Умурзакова, М. А., Усмонов, М. А., & Рахимов, М. Н. (2021). АНАЛОГИЯ РЕЙНОЛЬДСА ПРИ ТЕЧЕНИЯХ В ДИФФУЗОРНО-КОНФУЗОРНЫХ КАНАЛАХ. Экономика и социум, (3-2), 479-486.

3. ugli Mo'minov, O. A., Maqsudov, R. I., & qizi Abdukhalilova, S. B. (2021). Analysis of Convective Finns to Increase the Efficiency of Radiators used in Heating Systems. Middle European Scientific Bulletin, 18, 84-89.

4. Mo'minov, O. A. O'tbosarov Sh. R."Theoretical analysis of the ventilation emitters used in low-temperature heat supply systems, and heat production of these emitters" Eurasian journal of academic research, 495-497.

5. Рашидов, Ю. К., Орзиматов, Ж. Т., Эсонов, О. О. У., & Зайнабидинова, М. И. К. (2022). СОЛНЕЧНЫЙ ВОЗДУХОНАГРЕВАТЕЛЬ С ВОЗДУХОПРОНИЦАЕМЫМ МАТРИЧНЫМ АБСОРБЕРОМ. Scientific progress, 3(4), 1237-1244.

INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7 UIF-2022: 8.2 | ISSN: 2181-3337

6. Рашидов, Ю. К., Орзиматов, Ж. Т., & Исмоилов, М. М. (2019). Воздушные солнечные коллекторы: перспективы применения в условиях Узбекистана. ББК 20.1 я43 Э 40.

7. Madaliev, M. E. U., Maksudov, R. I., Mullaev, I. I., Abdullaev, B. K., & Haidarov, A. R. (2021). Investigation of the Influence of the Computational Grid for Turbulent Flow. Middle European Scientific Bulletin, 18, 111-118.

8. Hamdamalievich S. A. Determination of the deposition of particles contained in the water passing through the sump well //Central asian journal of theoretical & applied sciences. -2022. - Т. 3. - №. 6. - С. 244-251.

9. Maqsudov, R. I., & qizi Abdukhalilova, S. B. (2021). Improving Support for the Process of the Thermal Convection Process by Installing. Middle European Scientific Bulletin, 18, 5659.

10. Усаров, Махаматали Корабоевич, and Гиёсиддин Илхомидинович Маматисаев. "КОЛЕБАНИЯ КОРОБЧАТОЙ КОНСТРУКЦИИ КРУПНОПАНЕЛЬНЫХ ЗДАНИЙ ПРИ ДИНАМИЧЕСКИХ ВОЗДЕЙСТВИЯХ." Научный форум: технические и физико-математические науки. 2019.

11. Usmonova, N. A., & Khudaykulov, S. I. (2021, April). SPATIAL CAVERNS IN FLOWS WITH THEIR PERTURBATIONS IMPACT ON THE SAFETY OF THE KARKIDON RESERVOIR. In E-Conference Globe (pp. 126-130

12. Nosirov A.A., №sirov I.A. Simulation of Spatial Own of Vibrations of Axisymmetric Structures EUROPEAN MULTIDISCIPLINARY JOURNAL OF MODERN SCIENCE http s://emjms.academicj ournal .i o

13. Shavkatjon o'g'li, T. B. (2022). SOME INTEGRAL EQUATIONS FOR A MULTIVARIABLE FUNCTION. Web of Scientist: International Scientific Research Journal, 3(4), 160-163.

14. Abobakirovich, A. B., Sodikovich, A. Y., & Оgli, M. I. I. (2019). Optimization of operating parameters of flat solar air heaters. Вестник науки и образования, (19-2 (73)), 6-9.

15. Usmonova, N. A. (2021). Structural Characteristics of the Cavern at a Fine Bubbled Stage of Cavitation. Middle European Scientific Bulletin, 18, 95-101.

16. Nasirov Ismail Azizovich. On The Accuracy of the Finite Element Method on the Example of Problems about Natural Oscillations. EUROPEAN MULTIDISCIPLINARY JOURNAL OF MODERN SCIENCE https://emjms.academicjournal.io

17. Nosirov A.A., №sirov I.A. Simulation of Spatial Own of Vibrations of Axisymmetric Structures EUROPEAN MULTIDISCIPLINARY JOURNAL OF MODERN SCIENCE http s://emjms.academicj ournal .i o

18. Madaliev, E. U., & qizi Abdukhalilova, S. B. (2022). Repair of Water Networks. CENTRAL ASIAN JOURNAL OF THEORETICAL & APPLIED SCIENCES, 3(5), 389-394.

19. . Malikov, Z. M., & Madaliev, E. U. (2019). Mathematical simulation of the speeds of ideally newtonovsky, incompressible, viscous liquid on a curvilinearly smoothed pipe site. Scientific-technical journal, 22(3), 64-73.

20. Мадхадимов, М. М., Абдулхаев, З. Э., & Сатторов, А. Х. (2018). Регулирования работы центробежных насосов с изменением частота вращения. Актуальные научные исследования в современном мире, (12-1), 83-88.

INTERNATIONAL SCIENTIFIC JOURNAL VOLUME 1 ISSUE 7 UIF-2022: 8.2 | ISSN: 2181-3337

21. Hamdamalievich S. A., Nurmuhammad H. Analysis of Heat Transfer of Solar Water Collectors //Middle European Scientific Bulletin. - 2021. - Т. 18. - С. 60-65.

22. Xamdamaliyevich, S. A., & Rahmankulov, S. A. (2021, July). Investigation of heat transfer processes of solar water, air contact collector. In E-Conference Globe (pp. 161-165).

23. Madaliev, M. E. U., Rakhmankulov, S. A., & Tursunaliev, M. M. U. (2021). Comparison of Finite-Difference Schemes for the Burgers Problem. Middle European Scientific Bulletin, 18, 76-83

24. Abdullayev, B. X., & Rahmankulov, S. A. (2021). Modeling Aeration in High Pressure Hydraulic Circulation. CENTRAL ASIAN JOURNAL OF THEORETICAL & APPLIED SCIENCES, 2(12), 127-136.

25. Abdukarimov, B. A., O'tbosarov, S. R., & Tursunaliyev, M. M. (2014). Increasing Performance Efficiency by Investigating the Surface of the Solar Air Heater Collector. NM Safarov and A. Alinazarov. Use of environmentally friendly energy sources.

26. Rashidov, Y. K., & Ramankulov, S. A. (2021). Improving the Efficiency of Flat Solar Collectors in Heat Supply Systems. CENTRAL ASIAN JOURNAL OF THEORETICAL & APPLIED SCIENCES, 2(12), 152-159

27. Madraximov, M. M., Nurmuxammad, X., & Abdulkhaev, Z. E. (2021, November). Hydraulic Calculation Of Jet Pump Performance Improvement. In International Conference On Multidisciplinary Research And Innovative Technologies (Vol. 2, pp. 20-24).

28. Akramov, A. A. U., & Nomonov, M. B. U. (2022). Improving the Efficiency Account Hydraulic of Water Supply Sprinklers. Central Asian Journal of Theoretical and Applied Science, 3(6), 364-370.

29. Сатторов, А. Х., Акрамов, А. А. У., & Абдуразаков, А. М. (2020). Повышение эффективности калорифера, используемого в системе вентиляции. Достижения науки и образования, (5 (59)), 9-12.

30. Усаров, М. К., and Г. И. Маматисаев. "Вынужденные колебания коробчатой конструкции панельных зданий при динамических воздействиях." Проблемы механики 2 (2010): 23-25.

31. Shavkatjon o'g'li, T. B. (2022). Proving The Inequalities Using a Definite Integral and Series. Texas Journal of Engineering and Technology, 13, 64-68.