CC BY
9
https://doi.org/10.21122/2227-1031-2021-20-5-445-448 UDC 621.57
Automobile Absorption Conditioner
A. Р. Ilyin 1), A. N. Terentiev1), F. R. Arslanov2)
1)Kalashnikov Izhevsk State Technical University (Izhevsk, Russian Federation),
2)Izhevsk State Agricultural Academy (Izhevsk, Russian Federation)
© Белорусский национальный технический университет, 2021 Belarusian National Technical University, 2021
Abstract. The purpose of this study is to develop a circuit for an automobile air conditioner, which will reduce the consumption of power developed by the engine. This paper proposes the design of an automobile absorption air conditioner. A description of the principle of operation of an automobile absorption air conditioner operating on a cycle of a one-stage absorption refrigeration machine has been given in the paper. It consists of a stripper (generator), a condenser, an absorber, an evaporator. Lithium bromide (LiBr) solution has been used as an absorbent, which has a low boiling point, is non-toxic and safe. 3D-models of the absorber and generator of an automobile absorption air conditioner has been developed in the course of the research. The absorber is designed to form a weak absorbent solution. This solution is supplied to the generator heat exchanger using a liquid pump. There it is heated by the exhaust gases to the boiling point. The solution evaporates and water vapor enters the condenser (evaporator). In the generator, the solution is concentrated from 52 to 60 %. After that, water vapor is supplied to the absorber from the condenser, and a concentrated absorbent solution is supplied from the generator. It should be noted that the generator is a key element of an automobile absorption air conditioning system. Inside it is a strong LiBr solution that feeds the absorber. The design of the air conditioning system does not provide for the use of a compressor and allows to reduce the power loss of the power plant to the drive of the liquid pump. According to calculations, the pump drive power was 0.17 kW. For comparison, the compressor of a modern car air conditioner consumes 7-11 kW. An absorption car air conditioner provides the following advantages: additional engine cooling, environmental friendliness, fuel economy, efficient use of the heat of vehicle exhaust gases. A distinctive feature of this design is that it is proposed to use the heat of the exhaust gases for the process of heating the absorbent. This design can fully compete with the existing modern car air conditioners.
Keywords: automobile conditioner, absorption bromide-lithium refrigerating machine, absorption, absorber, desorber, lithium bromide, exhaust gases
For citation: Ilyin A. Р., Terentiev A. N., Arslanov F. R. (2021) Automobile Absorption Conditioner. Science and Technique. 20 (5), 445-448. https://doi.org/10.21122/2227-1031-2021-20-5-445-448
Автомобильный абсорбционный кондиционер
Кандидаты техн. наук, доценты А. П. Ильин4, А. Н. Терентьев1), Ф. Р. Арсланов2)
1)Ижевский государственный технический университет имени М. Т. Калашникова (Ижевск, Российская Федерация),
2)Ижевская государственная сельскохозяйственная академия (Ижевск, Российская Федерация)
Реферат. Целью исследования являлась разработка схемы автомобильного кондиционера, позволяющего снизить потребление развиваемой двигателем мощности. Предложена конструкция и приведено описание принципа действия автомобильного абсорбционного кондиционера, работающего по циклу одноступенчатой абсорбционной холодильной
Адрес для переписки Address for correspondence
Ильин Алексей Петрович Ilyin Alexey P.
Ижевский государственный технический университет Kalashnikov Izhevsk State
имени М. Т. Калашникова Technical University
ул. Студенческая, 7, 7, Studencheskaya str.,
426069, г. Ижевск, Российская Федерация 426069, Izhevsk, Russian Federation
Тел.: +79 090 67-22-71 Tel.: +79 090 67-22-71
ilalp@inbox.ru ilalp@inbox.ru
■■ Наука
итехника. Т. 20, № 5 (2021)
машины. Она состоит из десорбера (генератора), конденсатора, абсорбера, испарителя. В качестве абсорбента использовали раствор бромида лития (УБг), который имеет низкую температуру кипения, не токсичен и безопасен. В процессе исследования разработаны 3D-модели абсорбера и генератора абсорбционного автомобильного кондиционера. Абсорбер предназначен для образования слабого раствора абсорбента, который при помощи жидкостного насоса поступает в теплообменник генератора, где нагревается отработавшими газами до температуры кипения. Раствор испаряется, и пар идет в конденсатор (испаритель). В генераторе раствор концентрируется от 52 до 60 %. После этого в абсорбер из конденсатора поступает водяной пар, а из генератора - концентрированный раствор абсорбента. Следует заметить, что генератор является ключевым элементом системы абсорбционного автомобильного кондиционера. Внутри него находится крепкий раствор LiBг, питающий абсорбер. Конструкция системы кондиционера не предусматривает использование компрессора и позволяет снизить потери мощности силовой установки на привод жидкостного насоса. Согласно расчетам, мощность привода насоса составила 0,17 кВт. Для сравнения, компрессор современного автомобильного кондиционера потребляет 7-11 кВт. Абсорбционный автомобильный кондиционер имеет следующие преимущества: дополнительное охлаждение двигателя, экологичность, экономию топлива, эффективное использование теплоты выхлопных газов автомобиля. Отличительная особенность данной конструкции в том, что для процесса нагрева абсорбента используется теплота отработавших газов. Такая конструкция может составить полноценную конкуренцию имеющимся современным автомобильным кондиционерам.
Ключевые слова: автомобильный кондиционер, абсорбционная бромисто-литиевая холодильная машина, абсорбция, абсорбер, десорбер, бромид лития, отработавшие газы
Для цитирования: Ильин, А. П. Автомобильный абсорбционный кондиционер / А. П. Ильин, А. Н. Терентьев, Ф. Р. Арсланов // Наука и техника. 2021. Т. 20, № 5. С. 445-448. https://doi.org/10.21122/2227-1Q31-2Q21-2Q-5-445-448
The car air conditioning system is actively progress. A lot of research is implement to improve the design. Much attention is pay to improving the evaporator heat exchanger and other details of existing systems [1, 2]. In addition, new air conditioning systems are being developed. For example, using an ejector [3]. Research is being conducted to select a new, more efficient type of refrigerants [4, 5]. The results of these studies, to one degree or another, solve the problem of improving the efficiency of the vehicle air conditioning system.
Air conditioning systems based on new principles are of great interest. These include systems based on an absorption refrigeration cycle. Ammonia or lithium bromide solution is considered as a refrigerant [6, 7].
A modern automobile conditioner averagely consumes from 3 up to 6 kW of power produced by the engine. The significant decrease of the mechanical losses on the conditioner drive can be achieved removing the compressor, which drives the cold carrier in the cooling system, from the system.
The conditioner adapted for the cycle of absorption bromide-lithium refrigerating machine (ABRM) can be used to produce cold, apart from the compression-type conditioner. In contrast to the compression method, where the single-phase cold carrier (freon) circulates in the refrigerating loop, in the absorption one the mixture of water and absorbent is used. Lithium bromide with low
boiling temperature (90 0C) is used as an absorbent. When moving along the refrigerating loop, this mixture splits into the components and then mixes again [8]. There is no compressor in ABRM design, the engine power is only consumed for the liquid pump drive providing the transport of strong and concentrated solution. ABRM functional scheme is given in Fig. 1.
m
Absorber pump
Fig. 1. Absorption bromide-lithium refrigerating machine functional scheme
The main elements of this device are: desor-ber (generator), condenser, absorber and evaporator. There are also auxiliary elements providing the reliability and safety of the refrigerating machine operation. These are different shutoff, throttle, solenoid valves and automation system.
Наука
итехника. Т. 20, № 5 (2021)
The water vapor, formed under the action of cooled medium, comes from the evaporator to the absorber with the strong lithium bromide solution. As a result of water vapor and solution absorption, the concentration of the latter decreases [9, 10]. With the help of the liquid pump the weak solution is fed through the heat exchanger fixed on the exhaust pipe of the outlet header. Going through the heat exchanger, the solution is heated up and gets into the generator where it boils. The water vapor formed is fed into the condenser where it is condensed. The solution obtains low concentration again in the generator and gets into the absorber with the help of the bypass valve. Along the system pipes the condensate is fed into the evaporator. Thus the process cyclicality is provided.
The absorber (Fig. 2) is of closed type placed in one body with the evaporator. The desor-ber (generator) (Fig. 3) is the key element of the absorption automobile conditioner system. Strong LiBr solution, feeding the absorber, is inside the body.
Water vapor from the evaporator
Absorbent
strong
solution
Outlet
of the absorbent weak solution
Fig. 2. Absorber 3D-model
Water vapor
from the boiling weak
solution
1
Feed
of the weak solution
Feed of the strong solution to the absorber
Fig. 3. Desorber 3D-model
The condenser (Fig. 4) consists of copper U-pipes, aluminum plates and brackets of galvanized steel. U-pipes are interconnected by the method of copper U-bends soldering. The couples in the heat exchanger pipes are permanently and uniformly blown by the outer air, which is fed by the fan.
Copper pipe
Mounting bracket Aluminum lamella
Fig. 4. Air-cooled condenser
The evaporator (Fig. 5) in absorption automobile conditioner is a starting point of the whole process. In the hot season, the warm outer air flows through the evaporator pipes with the help of the fan. As a result, the water circulating along the pipes starts evaporating producing water vapor, which is fed to the absorber via the special nozzle where it gets absorbed with LiBr solution.
Cold carrier outlet
Cold carrier inlet
Warm air from the fan
Fig. 5. Evaporator
Exhaust Gas Recirculation (EGR) is used in modern vehicles. This system is designed to improve engine efficiency and reduce fuel consumption [11]. One of the elements in the EGR-system is a shell-and-tube heat exchanger (Fig. 6), through the tubes of which the exhaust gases pass from the exhaust manifold of the engine.
Fig. 6. Exhaust Gas Recirculation heat exchanger
HayKa
uTexHMKa. T. 20, № 5 (2021)
In this paper, it is proposed to introduce the EGR-system heat exchanger into the absorption cycle of the vehicle air conditioning system.
The liquid pump provides the forced cold carrier circulation in the absorption conditioner system. With its help, a weak LiBr solution is fed to the generator from the absorber. The automobile absorption conditioner design is given in Fig. 7.
a
Fig. 7. Automobile absorption conditioner design: a - schematic diagram; b - 3D-model of the conditioning system; 1 - absorber; 2 - desorber; 3 - evaporator; 4 - condenser; 5 - liquid pump; 6 - heat exchanger;
7 - evaporator fan; 8 - condenser fan; 9 - bypass valve
CONCLUSION
Thus, the design of an automobile absorption air conditioner has been developed. The main elements of this device are: desorber (generator), condenser, absorber and evaporator. Lithium bromide is proposed to be used as an absorbent. It has a low boiling point. Lithium bromide is non-toxic and safe. The resulting design of the air conditioner reduces the power loss of the power plant to drive the liquid pump. According to calculations, the pump drive power was 0.17 kW. For comparison, the compressor of a modern car air conditioner consumes 7-11 kW. An absorption car air conditioner provides the following advantages: additional engine cooling, environmental friendliness, fuel economy, efficient use of heat from vehicle
exhaust gases. This design can compete well with existing modern car air conditioners.
REFERENCES
1. Kaynakli O., Horuz 1. (2003) An Experimental Analysis of Automotive Air Conditioning System. International Communications in Heat and Mass Transfer, 30 (2), 273-284. https://doi.org/10.1016/s0735-1933(03)00038-1.
2. Lee G. H., Yoo J. (2000) Performance Analysis and Simulation of Automobile Air Conditioning System. International Journal of Refrigeration, 23 (3), 243-254. https:// doi.org/10.1016/S0140-7007(99)00047-X.
3. Arifianto E. S., Berman E. T., Mutaufiq M. (2018) Investigation on the Improvement of Car Air Conditioning System Performance Using an Ejector. MATEC Web of Conferences, 197, 08013. https://doi.org/10.1051/matecconf/ 201819708013.
4. Santoso Budi, Tjahjana D. D. D. P. (2017) Performance Analysis of the Electric Vehicle Air Conditioner by Replacing Hydrocarbon Refrigerant. AIP Conference Proceedings, 1788, 030015. https://doi.org/10.1063/L4968268.
5. Steven Brown J., Yana-Motta Samuel F., Domanski Piotr A. (2002) Comparative Analysis of an Automotive Air Conditioning Systems Operating with CO2 and R134a. International Journal of Refrigeration, 25 (1), 19-32. https:// doi.org/10.1016/s0140-7007(01 )00011-1.
6. Vicatos G., Gryzagoridis J., Wang S. (2008) A Car Air-Conditioning System Based on an Absorption Refrigeration Cycle Using Energy from Exhaust Gas of an Internal Combustion Engine. Journal of Energy in Southern Africa, 19 (4), 6-11. https://doi.org/10.17159/2413-3051/ 2008/v19i4a3331.
7. Patel M. (2017) Experimental Setup of Automotive Air-Conditioning Based on Vapor Absorption Refrigeration System. International Journal of Advance Engineering and Research Development, 4 (4). https://doi.org/10.210 90/ijaerd.me072.
8. Dantex Conditioners for a Metropolis. Available at: https://dantex.ru/ articles/absorbtsionnye-chillery (in Russian).
9. Voitekunas R. P., Ilyin A. P. (2018) Development of Passenger Compartment Conditioning Systems. Human in Natural, Social and Socio-Cultural Surroundings: Proceedings of II Regional Student Scientific-Practical Conference Dedicated to 25th Anniversary of Eastern-European University. Izhevsk, 98-106 (in Russian).
10. Electric Liquid Pump of a Cooling System. Available at: https://ustroistvo-avtomobilya.ru/ sistemy-hlazhdeniya/e-lektricheskij-zhidkostny-j-nasos (in Russian).
11. Purpose of the EGR-System and Features of its Operation. Available at: https://techautoport.ru/dvigatel/vypusknaya-sistema/sistema-egr.html (in Russian).
Received: 08.10.2019 Accepted: 10.12.2019 Published online: 30.09.2021
Наука
итехника. Т. 20, № 5 (2021)
