Overall Optimization and Exergy Analysis of an Air Conditioning System Using a Series-Series Counterflow Arrangement of Water Chillers

When water chillers are arranged in series-series counterflow (SSCF), the compressor lift of each chiller is decreased in comparison with that of water chillers in parallel. This means that the compressor power of SSCF chillers is lower than that of parallel chillers. In this paper, models of the main components in an air conditioning system were developed and verified to predict the behaviors of the whole system with respect to SSCF chillers. The results showed that performance was maximized with three SSCF chillers when the system was operated with normal set points. The performance was further improved to 26% and decreased with the number of SSCF chillers when the system was operated with optimal set points. The SSCF chiller system also demonstrated higher exergy efficiency regardless of the number of SSCF chillers. The irreversibility of components in SSCF chillers was rather low. However, the irreversibility of the cooling tower and cooling coil was slightly higher and lower, respectively, than those in the parallel chiller system.

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Exergy Analysis of Energy Consumption for Central Air Conditioning System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.628.332 ◽

2014 ◽

Vol 628 ◽

pp. 332-337

Author(s):

Xiao Xia Xia ◽

Nai Jun Zhou ◽

Zhi Qi Wang

Keyword(s):

Energy Consumption ◽

Air Conditioning ◽

Exergy Analysis ◽

Exergy Efficiency ◽

Dew Point ◽

Exergy Loss ◽

Air Conditioning System ◽

Air Cooler ◽

Central Air Conditioning ◽

Air Conditioning Systems

The energy consumption of several central air conditioning systems in summer was researched by the method of exergy analysis. Combined with actual example,the exergy loss of all the equipments and the exergy efficiency of three systems were calculated. The results show that the exergy efficiency of three systems is very low. Relatively speaking, the exergy efficiency of primary return air conditioning system with supplying air in dew point is highest. The equipment of highest exergy loss is air-conditioned room, while the exergy loss of surface air cooler is smallest. Based on this, several improvement measures were proposed to reduce exergy loss and improve exergy efficiency.

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Exergy Analysis of an Air Conditioning System Using Air-Cooled Condenser at Different Ambient Conditions with Different Volume Flow Rates of Air

Proceedings of International Conference in Mechanical and Energy Technology - Smart Innovation, Systems and Technologies ◽

10.1007/978-981-15-2647-3_55 ◽

2020 ◽

pp. 597-605

Author(s):

Taliv Hussain ◽

Adnan Hafiz ◽

Akramuddin

Keyword(s):

Air Conditioning ◽

Exergy Analysis ◽

Volume Flow ◽

Ambient Conditions ◽

Air Conditioning System ◽

Flow Rates

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Thermal Performance Analysis of Low-GWP Refrigerants in Automotive Air-Conditioning System

Advances in Materials Science and Engineering ◽

10.1155/2020/7967812 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14 ◽

Cited By ~ 2

Author(s):

Yousuf Alhendal ◽

Abdalla Gomaa ◽

Gamal Bedair ◽

Abdulrahim Kalendar

Keyword(s):

Air Conditioning ◽

Cooling Capacity ◽

Coefficient Of Performance ◽

Exergy Destruction ◽

Air Conditioning System ◽

Capacity Coefficient ◽

Automotive Air Conditioning ◽

Automotive Air Conditioning System ◽

Compressor Power ◽

Low Global Warming Potential

The energy and exergy of low-global warming potential (GWP) refrigerants were investigated experimentally and theoretically. Refrigerants with a modest GWP100 of ≤ 150 can be sufficient for bringing down emissions which were concerned for the automotive air-conditioning system. Three types of low-GWP refrigerants, R152a, R1234yf, and R1234ze(E), were examined with particular reference to the current high-GWP of R134a. The effect of different evaporating and condensing temperatures in addition to compressor speed was considered. The purpose was to bring a clear view of the performance characteristics of possible environment friendly alternatives of R134a. The analysis was carried out with compressor power, cooling capacity, coefficient of performance, exergy destruction, and exergy efficiency. It was noted that the total exergy destruction of R1234yf was reduced by 15% compared to that of R134a. The refrigerant R1234ze(E) has the highest energetic and exergetic performance compared with the other investigated refrigerants.

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Quantification on the Effects of Liquid-Vapor Separation in Air-Conditioning System by using Advanced Exergy Analysis

Journal of Thermal Science ◽

10.1007/s11630-020-1295-1 ◽

2020 ◽

Vol 29 (3) ◽

pp. 597-608

Author(s):

Yunhai Li ◽

Jianyong Chen ◽

Xu Lin ◽

Zhi Yang ◽

Ying Chen ◽

...

Keyword(s):

Air Conditioning ◽

Exergy Analysis ◽

Air Conditioning System ◽

Liquid Vapor

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Exergy Analysis on a Split-Type Conditioner Using Ejector as an Expansion Device

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.699.828 ◽

2014 ◽

Vol 699 ◽

pp. 828-833 ◽

Cited By ~ 1

Author(s):

Sumeru ◽

Markus ◽

Farid Nasir Ani ◽

Henry Nasution

Keyword(s):

Performance Improvement ◽

System Performance ◽

Air Conditioning ◽

Exergy Analysis ◽

Energy Savings ◽

Air Conditioner ◽

Total Energy Consumption ◽

Air Conditioning System ◽

Air Conditioners ◽

Exergy Losses

Air conditioning system consumes approximately 50% of the total energy consumption of buildings. Split-type air conditioner is the most widely used in residential and commercial buildings. As a result, enhancement on the performance of the air conditioners will yield a significant energy savings. The use of ejector as an expansion device on the split-type air conditioners is one method to increase the system performance. Exergy analysis on a split-type air conditioner uses an ejector as an expansion device at room and outdoor temperatures of 24 °C and 34 °C, respectively, yielded the percentage of exergy reduction up to 40.6%. Also, the exergy losses on in the compressor had the highest impact on the performance improvement of the split-type air conditioner.

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EXERGY ANALYSIS OF THE PERFORMANCE OF A VARIABLE REFRIGERANT FLOW (VRF) AIR CONDITIONING SYSTEM

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132511000405 ◽

2011 ◽

Vol 19 (01) ◽

pp. 57-68 ◽

Cited By ~ 5

Author(s):

MIGUEL PADILLA

Keyword(s):

System Performance ◽

Air Conditioning ◽

Exergy Analysis ◽

Control Volume ◽

Hvac Systems ◽

Coefficient Of Performance ◽

Cooling Load ◽

Air Conditioning System ◽

Operational Conditions ◽

Highly Sensitive

Commercial multiple evaporators variable refrigerant flow (VRF) HVAC systems present many advantages such as being energy saving and the capability of adjusting refrigerant mass flow rate according to the change of high rises occurrence. This paper deals with an experimental control volume exergy analysis in a VRF air conditioning system. The experimental results show that the brunt of the total exergy destroyed in the whole system occurs in the outdoor unit, where the exergy destroyed in the condenser is more important. The values of coefficient of performance (COP) obtained for the tests increase as the system reaches operational conditions imposed in every indoor unit zone. The VRF system analyzed is highly sensitive to the action of the constant speed compressor. The use of an inverter compressor improves the system performance by adjusting the power consumption according to the cooling load in the evaporators.

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