scholarly journals ВИЗНАЧЕННЯ ПРОЕКТНОЇ ХОЛОДОПРОДУКТИВНОСТІ СИСТЕМИ КОНДИЦІЮВАННЯ ПОВІТРЯ В КОНКРЕТНИХ КЛІМАТИЧНИХ УМОВАХ І РІЗНИМИ МЕТОДАМИ

2019 ◽  
pp. 15-19
Author(s):  
Євген Іванович Трушляков ◽  
Андрій Миколайович Радченко ◽  
Сергій Анатолійович Кантор ◽  
Веніамін Сергійович Ткаченко ◽  
Сергій Георгійович Фордуй ◽  
...  
Keyword(s):  
Power Plant ◽  
Fuel Consumption ◽  
Air Conditioning ◽  
Maximum Rate ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Temperate Climate ◽  
Air Cooling ◽  
Air Conditioning System ◽  
Air Conditioning Systems

The cold output for the heat-moisture treatment of ambient air in air conditioning systems depends on its parameters (temperature and relative humidity), which vary significantly during operation. To determine the installed (design) cooling capacity of air conditioning system chillers, it is proposed to use a reduction in fuel consumption of a power plant or cooling capacity generation following its current conditioning spending over a certain period, since both of these indicators characterize the efficiency of using the installed cooling capacities of the air conditioning system. To extend the results of the investigation to a wide range of air conditioning units, two methods were used to determine the design cooling capacity (refrigerating capacity): by the maximum annual value and by the maximum growth rate of the efficiency indicator. The first method allows choosing the design cooling capacity, which provides a maximum annual reduction in the specific fuel consumption due to air cooling or maximum cooling capacity generation, which is necessary for air cooling following current climatic conditions. The second method allows determining the minimum design (installed) cooling capacity of chillers, which provides the maximum rate of reduction in fuel consumption by the power plant and the increment in the annual cooling capacity generation following the installed cooling capacity of chillers. The efficiency of air conditioning systems was analyzed for different climatic conditions: a temperate climate using the example of Voznesensk city (Ukraine) and the subtropical climate of Nanjing city (China). It is shown that the design cooling capacity values calculated by both indicators of its use efficiency are the same for the same climatic conditions. Wherein, if to determine the design cooling capacity by both methods - by the maximum annual value and the maximum rate of growth of the indicator, its values turned out to be quite close for tropical climatic conditions and somewhat different for a temperate climate.

scholarly journals ХОЛОДОПРОДУКТИВНІСТЬ СИСТЕМИ КОНДИЦІЮВАННЯ ЗОВНІШНЬОГО ПОВІТРЯ ЗА ПОТОЧНИМ ТЕПЛОВИМ НАВАНТАЖЕННЯМ

2019 ◽  
pp. 51-55
Author(s):  
Євген Іванович Трушляков ◽  
Андрій Миколайович Радченко ◽  
Микола Іванович Радченко ◽  
Ян Зонмін ◽  
Анатолій Анатолійович Зубарєв ◽  
...  
Keyword(s):  
Heat Load ◽  
Air Conditioning ◽  
Maximum Rate ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Outdoor Air ◽  
Air Conditioning System ◽  
Maximum Value ◽  
Current Consumption ◽  
Air Conditioning Systems

The efficiency of the outdoor air conditioning systems application depends on how full the installed cooling capacity is applied, that is, with a more complete load and for as long as the possible yearly duration in actual climatic conditions. The production of cold is taken as a criteria of a quantitative evaluation of the efficiency of applying the cooling capacity of air conditioning systems – the amount of cold produced in accordance with its current demand for air conditioning, which in turn depends on the current consumption of cooling capacity and its duration and equals to their multiplication. It is obvious that the maximum value of the current amount of cold produced/consumed indicates an effective application of the installed cooling capacity. However, since the current demands of cooling capacity and their duration, that is, the amount of cold produced/consumed, depending on the changing current climatic conditions, they are characterized by significant fluctuations, which makes it difficult to choose the installed cooling capacity of the air conditioning system. Obviously, if we determine the amount of cold produced/consumed by its current values and summarized during the year, it is possible to significantly simplify the choice of the installed cooling capacity. At the same time, the current amount of cold produced/consumed causes a change in the rate of increment of the annual cold production with a change in the installed cooling capacity, and the maximum rate corresponds to the installed cooling capacity, which provides its efficient use. Proceeding from a different rate of increment of annual cold production with an increase in the installed cooling capacity of the air conditioning system due to a change in heat load in accordance with current climatic conditions during the year, the value of design heat load on the air conditioning system (installed cooling capacity) that provides maximum or close to it the rate of increment of the annual production of cold, and hence the maximum efficient use of installed cooling capacity is chosen

scholarly journals АНАЛІЗ ЕКОЛОГІЧНОЇ ЕФЕКТИВНОСТІ СИСТЕМ КОНДИЦІЮВАННЯ ПОВІТРЯ КОМБІНОВАНОГО ТИПУ

2019 ◽  
pp. 24-29
Author(s):  
Євген Іванович Трушляков ◽  
Андрій Миколайович Радченко ◽  
Сергій Георгійович Фордуй ◽  
Анатолій Анатолійович Зубарєв ◽  
Сергій Анатолійович Кантор ◽  
...  
Keyword(s):  
Fuel Consumption ◽  
Air Conditioning ◽  
Maximum Growth ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Maximum Growth Rate ◽  
Climatic Conditions ◽  
Air Cooling ◽  
Carbon Dioxide Co2 ◽  
Air Conditioning Systems

Since the supply air conditioning systems operation effect depends on the cooling duration and depth, it is quite justified to estimate it by the value of the specific annual cold production, which is the product of the necessary cooling capacity for cooling the air to the target temperature multiplied by duration of operation at a given cooling capacity and, thus, considers current climatic conditions. Obviously, the realization of the cooling potential (air conditioning) of the ambient air depends on the installed (design) cooling capacity of the air conditioning units, which, in turn, must considering fluctuations in thermal loads by the current variable thermal and humidity parameters of the ambient air. With an increase in the temperature of the ambient air, fuel consumption for the production of a unit capacity (mechanical/electrical energy) increases, and, accordingly, the more harmful substances are removed to the atmosphere with exhaust gases. To reduce the negative impact of unproductive fuel consumption during the operation of air conditioning systems at elevated ambient temperatures, resort to various methods for determining the installed cooling capacity of the installation, to reduce it. In the work, the ecological efficiency of air cooling is studied considering the climatic operating conditions for the Kyiv city that are variable during the year. The annual reduction in emissions of carbon dioxide CO2 and nitric oxide NOX was chosen as indicators for assessing the environmental effect of air cooling. It has been shown that when choosing the installed cooling capacity, by the method of ensuring the maximum growth rate of the annual cold production considering the increase in the installed cooling capacity of the chiller, there is a greater reduction in specific fuel consumption compared to the method of choosing the maximum annual cold production, respectively, and harmful emissions. When comparing the methods for choosing the design cooling capacity, air cooling to 15 °C provides a reduction in carbon dioxide CO2 emissions of more than 34 t for 2017 for the climatic conditions of Kiev, in favor of the method of ensuring the maximum growth rate of annual cold production, and nitric oxide NOX – about 5,8 t.

scholarly journals ПІДВИЩЕННЯ ЕФЕКТИВНОСТІ СИСТЕМ КОНДИЦІЮВАННЯ ПОВІТРЯ ШЛЯХОМ РОЗПОДІЛУ ТЕПЛОВОГО НАВАНТАЖЕННЯ ЗА СТУПЕНЕВИМ ПРИНЦИПОМ

2019 ◽  
pp. 49-53
Author(s):  
Євген Іванович Трушляков ◽  
Микола Іванович Радченко ◽  
Андрій Миколайович Радченко ◽  
Сергій Георгійович Фордуй ◽  
Сергій Анатолійович Кантор ◽  
...  
Keyword(s):  
Thermal Load ◽  
Air Conditioning ◽  
Rational Design ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Outlet Temperature ◽  
Thermal Loads ◽  
Air Conditioning System ◽  
Air Conditioning Systems

Maintaining the operation of refrigeration compressors in nominal or close modes by selecting a rational design thermal load and distributing it in response to the behavior of the current thermal load according to the current climatic conditions is one of the promising reserves for improving the energy efficiency of air conditioning systems, which implementation ensures maximum or close to it in the annual cooling production according to air conditioning duties. In general case, the total range of current thermal loads of any air-conditioning system includes a range of unstable loads caused by precooling of ambient air with significant fluctuations in the cooling capacity according to current climatic conditions, and a range of relatively stable cooling capacity expended for further lowering the air temperature from a certain threshold temperature to the final outlet temperature. If a range of stable thermal load can be provided within operating a conventional compressor in a mode close to nominal, then precooling the ambient air with significant fluctuations in thermal load requires adjusting the cooling capacity by using a variable speed compressor or using the excess of heat accumulated at reduced load. Such a stage principle of cooling ensures the operation of refrigerating machines matching the behavior of current thermal loads of any air-conditioning system, whether the central air conditioning system with ambient air procession in the central air conditioner or its combination with the local indoors recirculation air conditioning systems in the air-conditioning system. in essence, as combinations of subsystems – precooling of ambient air with the regulation of cooling capacity and subsequent cooling air to the mouth of the set point temperature under relatively stable thermal load.

scholarly journals ВИЗНАЧЕННЯ ВСТАНОВЛЕНОЇ ХОЛОДОПРОДУКТИВНІСТІ СИСТЕМИ ОХОЛОДЖЕННЯ ПОВІТРЯ НА ВХОДІ ГАЗОТУРБІННОЇ УСТАНОВКИ ЗА ПОТОЧНИМ ТЕПЛОВИМ НАВАНТАЖЕННЯМ

2019 ◽  
pp. 56-60
Author(s):  
Андрій Миколайович Радченко ◽  
Ян Зонмін ◽  
Микола Іванович Радченко ◽  
Сергій Анатолійович Кантор ◽  
Богдан Сергійович Портной ◽  
...  
Keyword(s):  
Fuel Consumption ◽  
Maximum Rate ◽  
Cooling System ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Air Cooling ◽  
Consumption Reduction ◽  
Air Cooling System ◽  
Annual Reduction

Significant fluctuations of the current temperature and relative humidity of the ambient air lead to significant changes in the thermal load on the cooling system at the inlet of gas turbine units (GTU), which acutely raises the problem of choosing their installed (design) thermal load. Calculations of ambient air cooling processes were carried out for different climatic conditions, for example, southern Ukraine (Mykolaiv) and Central China (Beijing). It is  analyzed two methods of determination of the installed (design) cooling capacity of the ambient air cooling system at the GTU inlet according to the maximum current reduction of fuel consumption and according to the maximum rate (increase) of annual reduction of fuel consumption following to increasing of the installed cooling capacity, calculated by summarizing the current values of fuel consumption reduction. It is shown that the values of the installed cooling capacity of the air cooling system at the GTU inlet, determined by both methods, are close enough but differ significantly for different climatic conditions. The advantage of the method of calculating the installed cooling capacity of the air cooling system at the GTU inlet according to the maximum rate of annual reduction in fuel consumption is the possibility of a more precise definition of it due to the absence of significant fluctuations in the annual reduction in fuel consumption, calculated by summarizing the current values of fuel consumption reduction. Since the maximum reduction in fuel consumption per year is achieved with some decrease in the rate of its increment at high values of the design cooling capacity, required in the hottest hours in the summer and excessive in somewhat cool periods (at night and in the morning even in the summer), the installed cooling capacity, determined according to the maximum rate of the reduction of fuel consumption, will be insufficient in times of increased thermal loads above their design value. In such cases, the elimination of the deficit in cooling capacity is possible by using an excess of cold accumulated during reduced thermal loads

scholarly journals МЕТОД ВИЗНАЧЕННЯ ХОЛОДОПРОДУКТИВНОСТІ УСТАНОВОК КОНДИЦІЮВАННЯ ПОВІТРЯ КОМФОРТНОГО Й ЕНЕРГЕТИЧНОГО ПРИЗНАЧЕННЯ

2019 ◽  
pp. 53-58
Author(s):  
Євген Іванович Трушляков ◽  
Андрій Миколайович Радченко ◽  
Ян Зонмін ◽  
Анатолій Анатолійович Зубарєв ◽  
Веніамін Сергійович Ткаченко
Keyword(s):  
Fuel Consumption ◽  
Air Conditioning ◽  
Mechanical Energy ◽  
Heat Engine ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
High Rate ◽  
Air Cooling ◽  
Duration Of Operation

The efficiency of applying air conditioning units for comfort and energetics for a certain period, as well as any power plant, is determined by the effect obtained, primarily in the form of reducing fuel consumption over the year or increasing the production of electrical (mechanical) energy in the case of air conditioning at the heat engine inlet and by annual cold production as an indicator of the efficiency of using the cooling capacity of comfort air-conditioning plants. Since in both cases the effect depends on the duration and depth of cooling, it is quite justified to estimate it in the first approximation by the thermal hourly potential, which is the result of summation hour by hour of air temperature drops multiplied by duration of operation at a lowered temperature and, thus, takes into account current climatic conditions. Obviously, the realization of the cooling potential (air conditioning) of the ambient air depends on the installed (design) cooling capacity of the air conditioning units, which, in turn, must take into account the fluctuations in thermal loads in accordance with the current variable thermal and humidity parameters of the ambient air. Based on the different rates of the increment of the annual thermal hourly cooling potential with an increase in the installed cooling capacity of the air conditioning unit due to a change in the heat load in accordance with current climatic conditions during the year, it is necessary to choose such a design thermal load on the air conditioning unit (its installed cooling capacity) that ensures maximum or close to it the annual thermo-hour cooling potential at a relatively high rate of its increment, respectively, and the effect of cooling in the form of a decrease in fuel consumption per year in the case of air conditioning at the inlet of heat engine and annual cold production of comfort air conditioning units. It is shown that under the same climatic conditions during the year and the depth of ambient air cooling, the rational values of the design cooling capacity of air conditioning units for comfort and energy purposes are the same.

scholarly journals МЕТОДОЛОГІЧНІ ПІДХОДИ ДО ВИЗНАЧЕННЯ ХОЛОДОПРОДУКТИВНОСТІ СИСТЕМ КОНДИЦІЮВАННЯ ПОВІТРЯ ЗА ЗМІННИХ КЛІМАТИЧНИХ УМОВ

2019 ◽  
pp. 71-75
Author(s):  
Євген Іванович Трушляков ◽  
Андрій Миколайович Радченко ◽  
Микола Іванович Радченко ◽  
Сергій Георгійович Фордуй ◽  
Сергій Анатолійович Кантор ◽  
...  
Keyword(s):  
Heat Load ◽  
Air Conditioning ◽  
Rational Design ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Stable Range ◽  
Air Conditioning System ◽  
Air Conditioning Systems ◽  
Current Heat

One of the most attractive reserves for improving the energy efficiency of air conditioning systems is to ensure the operation of refrigeration compressors in nominal or close to nominal modes by selecting a rational design heat load and distributing it within its design value according to the behavior of the current heat load under variable current climatic conditions to provide the maximum or close to maximum annual cooling capacity generation according to cooling duties of air conditioning. In the general case, the overall range of current thermal loads of any air conditioning system includes a range of unstable loads associated with the precooling of ambient air with significant fluctuations in cooling capacity according with current climatic conditions, and a relatively stable range of cooling capacity consumed to further reduce air temperature from a certain threshold temperature to the final outlet temperature. It is quite obvious that a stable range of heat load can be ensured within operating a conventional compressor in a mode close to the nominal mode while precooling the ambient air with significant fluctuations in heat load requires regulation of the cooling capacity through the use of a variable speed compressor. Thus, in response of the behavior of the change in current heat loads, any air conditioning system, whether the central air-conditioning system with its heat procession in a central air conditioner, or a combination thereof with a local recirculation system of indoor air, essentially consists of two subsystems: pre-cooling the ambient air and then cooling it to the set point temperature. The proposed method of distribution of design heat load depending on the behavior of the current heat load is useful for the rational design of central air conditioning systems and their combined versions with the local air conditioning system.

ANALYSIS OF COMPETING VARIANTS OF AIR CONDITIONING SYSTEMS WITHOUT AIR EXTRACTION FROM ENGINES AT THE STAGE OF PASSENGER AIRCRAFT ONBOARD SYSTEMS CONCEPTUAL DESIGN

2019 ◽  
Vol 6 (3) ◽  
pp. 80-85
Author(s):  
Denis Igorevich Smagin ◽  
Konstantin Igorevich Starostin ◽  
Roman Sergeevich Savelyev ◽  
Anatoly Anatolyevich Satin ◽  
Anastasiya Romanovna Neveshkina ◽  
...  
Keyword(s):  
Conceptual Design ◽  
Air Conditioning ◽  
Research University ◽  
Cooling System ◽  
Fuel Efficiency ◽  
Air Cooling ◽  
Moscow Aviation Institute ◽  
Air Conditioning System ◽  
Low Efficiency ◽  
Air Conditioning Systems

One of the ways to achieve safety and comfort is to improve on-board air conditioning systems.The use of air cooling machine determines the air pressure high level at the point of selection from the aircraft engine compressor. Because of the aircraft operation in different modes and especially in the modes of small gas engines, deliberately high stages of selection have to be used for ensuring proper operation of the refrigeration machine in the modes of the aircraft small gas engines. Into force of this, most modes of aircraft operation have to throttle the pressure of the selected stage of selection, which, together with the low efficiency of the air cycle cooling system, makes the currently used air conditioning systems energy inefficient.A key feature of the architecture without air extraction from the main engines compressors is the use of electric drive compressors as a source of compressed air.A comparative analysis of competing variants of on-board air conditioning system without air extraction from engines for longrange aircraft projects was performed at the Moscow Aviation Institute (National Research University).The article deals with the main approaches to the decision-making process on the appearance of a promising aircraft on-board air conditioning system at the stage of its conceptual design and formulated the basic requirements for the structure of a complex criterion at different life cycle stages.The level of technical and technological risk, together with a larger installation weight, will require significant costs for development, testing, debugging and subsequent implementation, but at the same time on-board air conditioning system scheme without air extraction from the engines will achieve a significant increase in fuel efficiency at the level of the entire aircraft.

Analysis of the Behavior of an Air Conditioning System Based on the Solar Energy Natural Regulation in Amazonian Climatic Conditions

2020 ◽  
Vol 143 (3) ◽  
Author(s):  
Elson C. Santos ◽  
Emanuel N. Macêdo ◽  
Marcos A. B. Galhardo ◽  
Thiago Oliveira Costa ◽  
André Felipe P. Costa ◽  
...  
Keyword(s):  
Direct Current ◽  
Air Conditioning ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Power Modeling ◽  
Frequency Converters ◽  
Industrial Buildings ◽  
Air Conditioning Systems ◽  
Solar Resource ◽  
Installed Capacity

Abstract Air conditioning systems (ACSs) represent one of the main demands for electricity in residential, commercial, and industrial buildings. The use of a photovoltaic air conditioning unit (PVACU) represents an attractive application to this demand for reasons such as environmental concerns and the match between diurnal cooling load and solar resource. A PVACU consists of a photovoltaic generator (PVG) that supply an ACS through direct current to direct current and frequency converters, without energy storage. This system considers the natural adjustment of the ACS cooling capacity according to the PVG power. Modeling the ACS, the PVG, and the thermal load (TL) makes possible to evaluate PVACU performance. For this, a small library’s TL and an ACS supplied by a PVG were used as case study. The PVG installed capacity assumes values of 700, 1000, and 1400 Wp. The simulation results show that the PVACU with a 1400 Wp PVG would be sufficient to regulate internal temperature within international comfort standards in the range of 20 °C to 24 °C. According to the data obtained in the simulations, it was possible to conclude that the PVACU has a large potential to be used in air conditioning of other environments in regions with Amazonian climatic conditions.

scholarly journals Design and Analysis of a Thermoelectric Air-conditioning System

2020 ◽  
pp. 1-11
Author(s):  
A. Anthony Adeyanju ◽  
K. Manohar
Keyword(s):  
Air Conditioning ◽  
Thermoelectric Module ◽  
Cooling Capacity ◽  
Peltier Effect ◽  
Refrigeration Cycle ◽  
Air Conditioner ◽  
Air Conditioning System ◽  
Thermoelectric Air Conditioner ◽  
Air Conditioning Systems ◽  
Dc Current

Thermoelectric devices use the Peltier effect which creates a heat flux between the junctions of two different types of materials. The thermoelectric module also referred to as a heat pump transfers heat from one side to the other when a DC current is applied. This study carried out the theoretical and experimental analysis of a thermoelectric air conditioning system. A prototype thermoelectric air conditioner of 286 W cooling capacity was built and a testing enclosure made from plywood and Styrofoam was also constructed in order to validate the theoretical result with an experimentation. It was discovered that thermoelectric air conditioning took 4 minutes to reach its desired temperature of 22℃ whereas the standard air conditioning system (Refrigeration Cycle) took 20 minutes to cool to a room temperature. Economically it was also discovered that thermoelectric air conditioning system is 50% cheaper than the refrigeration cycle air conditioning systems. The thermoelectric air conditioner has cheaper maintenance and greater estimated life span of 7 years more than the refrigeration air conditioner. This is because the air conditioner that operates on the refrigeration cycle uses a rotating compressor while the thermoelectric air conditioner uses thermometric module.

scholarly journals The Experimental Assessment of R134a and Its Lower GWP Alternative R1234yf in an Automobile Air Conditioning System

2019 ◽  
Vol 25 (12) ◽  
pp. 1-14
Author(s):  
Rafah Hussain ◽  
Issam Mohammed Ali
Keyword(s):  
Ambient Temperature ◽  
Air Conditioning ◽  
Cooling Capacity ◽  
Air Conditioning System ◽  
Automotive Air Conditioning ◽  
Nominal Capacity ◽  
Automotive Air Conditioning System ◽  
And Performance ◽  
Air Conditioning Systems ◽  
Main Operating

Reducing global warming potential (GWP) of refrigerants is needed to the decrease of ozone-depleting of refrigeration systems leakages. Refrigerant R1234yf is now used to substitute R134a inside mobile air conditioning systems. Thermodynamic properties of R1234yf are similar to R134a. Also, it has a very low GWP of 4, compared to 1430 for R134a, making it a proper choice for future automobile refrigerants. The purpose of this research is to represent the main operating and performance differences between R1234yf and R134a. Experimental analysis was carried out on the automotive air conditioning system (AACS) with 3 kW nominal capacity, to test and compare the performance of R134a with R1234yf. Experiments were accomplished for both refrigerants in almost the same working conditions and procedure with a range of ambient temperature varied from 26oC to 50oC. Parameters studied were ambient temperature, type of refrigerant in the system at compressor speed 1450 rpm, and internal thermal loads of passenger room. The performance characteristics of the system, including COP and cooling capacity, were studied by changing different parameters. The results show that COP of R134a is higher than R1234yf by 12.6%, while the refrigeration effect of R134a is higher than R1234yf by 25%. This shows that R1234yf is a suitable and good candidate for drop-in replacement of R134a in AACS.

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