scholarly journals Simulation Analysis of the Four Configurations of Solar Desiccant Cooling System Using Evaporative Cooling in Tropical Weather in Malaysia

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
M. M. S. Dezfouli ◽  
S. Mat ◽  
G. Pirasteh ◽  
K. S. M. Sahari ◽  
K. Sopian ◽  
...  
Keyword(s):  
Air Conditioning ◽  
Simulation Analysis ◽  
Cooling System ◽  
High Energy ◽  
Coefficient Of Performance ◽  
Humidity Ratio ◽  
Two Stage ◽  
One Stage ◽  
Temperature And Humidity ◽  
Ventilation Modes

A high demand for air conditioning systems exists in hot and humid regions because of the warm climate during the year. The high energy consumption of conventional air conditioning system is the reason for our investigation of the solar desiccant cooling system as an energy-efficient cooling system. Four model configurations were considered to determine the best configuration of a solar desiccant cooling system: one-stage ventilation, one-stage recirculation, two-stage ventilation, and two-stage recirculation. These models were stimulated for 8,760 hr of operation under hot and humid weather in Malaysia. Several parameters (i.e., coefficient of performance or COP, room temperature and humidity ratio, and the solar fraction of each system) were evaluated by detecting the temperature and humidity ratio of the different points of each configuration by TRNSYS simulation. The latent and sensible loads of the test room were 0.875 kW and 2.625 kW, respectively. By investigating the simulation results of the four systems, the ventilation modes were found to be higher than the recirculation modes in the one- and two-stage solar desiccant cooling systems. The isothermal dehumidification COP of the two-stage ventilation was higher than that of the two-stage recirculation. Hence, the two-stage ventilation mode desiccant cooling system in a hot and humid area has higher efficiency than the other configurations.

Performance Test on a Solar Powered Two-Stage Solid Wheel Desiccant Air Conditioning System

2013 ◽  
Vol 732-733 ◽  
pp. 609-614
Author(s):  
Tong Hua Zou ◽  
Gu Jia ◽  
Fa Li Cao ◽  
Rong Yu
Keyword(s):  
Relative Humidity ◽  
Air Conditioning ◽  
Performance Test ◽  
Cooling System ◽  
Coefficient Of Performance ◽  
Outlet Temperature ◽  
Thermal Coefficient ◽  
Two Stage ◽  
Air Conditioning System ◽  
Solar Powered

In the paper, changes of both outlet temperature and relative humidity of solar powered two-stage wheel desiccant air conditioning system are tested with time under the typical Tianjin summer condition. It is found that supply air temperature of the solar driven desiccant cooling system could steady below 21 degrees Celsius, and the relative humidity of it is more than sixty percent in most of time of the actual operation. When operating, the thermal coefficient of performance of the whole air conditioning unit is about 0.5, and the reliability of two-stage wheel desiccant air conditioning system is verified.

scholarly journals A New Design of an Integrated Solar Absorption Cooling System Driven by an Evacuated Tube Collector: A Case Study for Baghdad, Iraq

2020 ◽  
Vol 10 (10) ◽  
pp. 3622 ◽  
Author(s):  
Adil Al-Falahi ◽  
Falah Alobaid ◽  
Bernd Epple
Keyword(s):  
Thermal Performance ◽  
Air Conditioning ◽  
Cooling System ◽  
Electrical Power ◽  
Energy Performance ◽  
Coefficient Of Performance ◽  
Solar Absorption ◽  
Air Conditioning System ◽  
Solar Fraction ◽  
Design Variables

The electrical power consumption of refrigeration equipment leads to a significant influence on the supply network, especially on the hottest days during the cooling season (and this is besides the conventional electricity problem in Iraq). The aim of this work is to investigate the energy performance of a solar-driven air-conditioning system utilizing absorption technology under climate in Baghdad, Iraq. The solar fraction and the thermal performance of the solar air-conditioning system were analyzed for various months in the cooling season. It was found that the system operating in August shows the best monthly average solar fraction (of 59.4%) and coefficient of performance (COP) (of 0.52) due to the high solar potential in this month. Moreover, the seasonal integrated collector efficiency was 54%, providing a seasonal solar fraction of 58%, and the COP of the absorption chiller was 0.44, which was in limit, as reported in the literature for similar systems. A detailed parametric analysis was carried out to evaluate the thermal performance of the system and analyses, and the effect of design variables on the solar fraction of the system during the cooling season.

scholarly journals System Design of Solar Absorption Cooling : A Case Study in Building of Engineering Physics Department UGM

KnE Energy ◽  
2015 ◽  
Vol 2 (2) ◽  
pp. 22
Author(s):  
Andang Widiharto ◽  
Didit Setyo Pamuji ◽  
Atik Nurul Laila ◽  
Fiki Rahmatika Salis ◽  
Luthfi Zharif ◽  
...  
Keyword(s):  
Global Warming ◽  
Solar Collector ◽  
Air Conditioning ◽  
Cooling System ◽  
Renewable Energy Sources ◽  
Coefficient Of Performance ◽  
Thermal Coefficient ◽  
Solar Absorption ◽  
Absorption Cooling ◽  
Solar Absorption Cooling

<p>Air conditioning (AC) is one of the most building’s energy consumer, included in building of Engineering Physisc’s Departement, Universitas Gadjah Mada (UGM). The declining of fossil fuel reserves and the increasing effects of global warming, forcing the world to switch to renewable energy sources. This paper discusses the design of solar absorption cooling system to replace conventional AC in seven lecture halls of Engineering Physic’s Departement, UGM. There are some steps that have been done to design the solar absorption cooling, i.e. do a study of the potential availability of solar energy, calculate the cooling loads, analyze the thermodynamic process of the system, determine the type of collector to be used and calculate area of solar collector needed. The thermal coefficient of performance (COP) of the system designed was about 0.84 which could use some types of flat plate solar collector with each area corresponding to each efficiency values. </p><p><strong>Keyword</strong> : Air conditioning; global warming; solar absorption cooling; solar collector</p>

Solid desiccant dehumidification-based air-conditioning system for agricultural storage application: Theory and experiments

2019 ◽  
Vol 234 (4) ◽  
pp. 534-547 ◽  
Author(s):  
Muhammad H Mahmood ◽  
Muhammad Sultan ◽  
Takahiko Miyazaki
Keyword(s):  
Air Conditioning ◽  
Evaporative Cooling ◽  
Ambient Air ◽  
Coefficient Of Performance ◽  
Postharvest Quality ◽  
Thermal Coefficient ◽  
Humidity Ratio ◽  
Factors Affecting ◽  
Experimental Apparatus ◽  
Quality Of Products

This study experimentally investigates desiccant dehumidification and indirect evaporative cooling for agricultural products' storage. Thermodynamic advantages of the proposed system are highlighted and compared to vapor compression systems. Significance of proposed system is discussed in relation to agricultural storage application. Factors affecting the postharvest quality of products are discussed, and consequently, the psychrometric zones are established for optimum storage. Hydrophilic polymeric sorbent-based desiccant units are used for the experimental investigation. An open-cycle experimental apparatus is setup by which desiccant dehumidification and regeneration processes are analyzed at various conditions. Thereby, a novel correlation is developed by which desiccant dehumidification process can be simulated precisely. The correlation is successfully validated against the experimental data of various conditions. Desiccant air-conditioning cycle is analyzed for two cases (i.e. case-A: dry-bulb temperature = 31 ℃, humidity-ratio = 6 g/kg-DA; and case-B: dry-bulb temperature = 13 ℃, humidity-ratio = 6 g/kg-DA) to investigate the proposed system's applicability for agricultural storage. The results show that the thermal coefficient of performance is highly influenced by ambient air conditions and decreases with the increase in regeneration temperature. The thermal coefficient of performance for case-A is higher as compared to case-B, and for both cases, it increases with the increase in wet-bulb effectiveness of the evaporative cooling unit.

scholarly journals Effect of Desiccant Solution Temperature on Regeneration Performance of a Cross-Flow Regenerator

2019 ◽  
Vol 111 ◽  
pp. 01086
Author(s):  
Hye-Won Dong ◽  
Hye-Jin Cho ◽  
Jae-Weon Jeong
Keyword(s):  
Aqueous Solution ◽  
Cross Flow ◽  
Optimal Solution ◽  
Experimental Tests ◽  
Coefficient Of Performance ◽  
Solution Temperature ◽  
Inlet Temperature ◽  
Humidity Ratio ◽  
Temperature And Humidity ◽  
The Cross

The purpose of this study is to investigate the effect of the inlet solution temperature on the performance of an adiabatic cross-flow regenerator using a lithium chloride (LiCl) aqueous solution, and to propose the optimal inlet solution temperature when operating this type of regenerator. In the experimental tests, the inlet solution temperature range varied from 50 to 90°C. The tests were carried out at 10°C intervals while the other conditions remained constant. The measurement parameters for the test were the inlet air dry-bulb temperature and humidity ratio, outlet air dry-bulb temperature and humidity ratio, air volume flow, solution density, and inlet and outlet solution temperatures. The regeneration effectiveness and coefficient of performance (COP) were selected to assess the heat and mass transfer performance of the cross-flow regenerator. The most important finding of this research was to determine the optimal solution inlet temperature in the cross-flow regenerator with the LiCl aqueous solution considering both the regenerator performance and energy consumption. The test results show that the recommended inlet solution temperature is 60°C, considering both regeneration effectiveness and COP.

Investigation of optimization of solar energy refrigerator with natural humidifier

2021 ◽  
Vol 8 (2) ◽  
Author(s):  
Santosa I D. M. C. ◽  
Waisnawa I N. G. S. ◽  
Sunu P. W. ◽  
Wirajati I G. A. B.
Keyword(s):  
Solar Energy ◽  
Cooling System ◽  
Ambient Air ◽  
Operating Conditions ◽  
Cold Chain ◽  
Coefficient Of Performance ◽  
Good Reliability ◽  
Tropical Country ◽  
Temperature And Humidity ◽  
Horticultural Products

Cold chain processes of horticultural products in tropical countries is very urgent to maintain product quality. In Indonesia, the temperature and humidity are relatively high, so that the deterioration of horticultural products is very fast. Because of the high humidity, this condition can highly possibly use a natural humidifier for a cold room by purging humid ambient air to the refrigerator cabin with the best certain time. Meanwhile, as a tropical country, solar energy has good reliability to be developed. This study aims to determine the performance of the medium temperature refrigerator with a natural humidifier using solar energy as energy source. This research was conducted as an experimental investigation. The rig has been built completely with measurements and instrumentation for precise temperature and humidity control. The results showed that the system reached a quite good coefficient of performance (COP), with the thermodynamically COP of 3.6. However, humidifiers contribute a cooling load which can affect the temperature increase of 1o C - 1.5o C in the cooling system. Further studies will examine the optimization of the refrigerator system with natural humidifiers with low electricity consumption and eco-operating conditions with the best combination of temperature and humidity to keep the product of good quality in a long storage time.

Thermoelectric Air-Conditioning System: Building Applications and Enhancement Techniques

2019 ◽  
Vol 27 (02) ◽  
pp. 1930002 ◽  
Author(s):  
Aklilu Tesfamichael Baheta ◽  
Kar Kin Looi ◽  
Ahmed Nurye Oumer ◽  
Khairul Habib
Keyword(s):  
Air Conditioning ◽  
Phase Change Materials ◽  
Cooling System ◽  
High Reliability ◽  
Coefficient Of Performance ◽  
Working Fluid ◽  
Future Research ◽  
Thermoelectric Cooling ◽  
Air Conditioning System ◽  
System Building

The high reliability, the absence of working fluid and auxiliary pipes in the thermoelectric cooling application have attracted the attention of researchers in the last two decades. However, the use of thermoelectric air-conditioning system for building application has not been entirely explored due to its low coefficient of performance (COP) compared to the conventional air conditioning system. To overcome this primary limitation, different COP enhancement techniques of thermoelectric for air conditioning system building application are made available. This paper provides the recent development of thermoelectric air conditioning system in building applications, such as thermoelectric radiant panel ceiling, thermoelectric air duct system and thermoelectric cooling facades. It also provides the different strategies to enhance its performance in order to fit this technology in real building applications such as the integration of water-cooling system, phase change materials, evaporator cooling system and nanofluid micro-channel heat sinks. Lastly, the challenges of thermoelectric air-conditioning systems and future research directions are discussed.

Hybrid Desiccant Cooling System Using Condensing Heat as the Regeneration Source. Part II: Energy Saving Potential

2011 ◽  
Vol 383-390 ◽  
pp. 6431-6435 ◽  
Author(s):  
Xing Han ◽  
Xu Zhang
Keyword(s):  
Energy Consumption ◽  
Cooling System ◽  
High Energy ◽  
System Model ◽  
Electrical Heating ◽  
Outdoor Air ◽  
Humidity Ratio ◽  
Air Conditioning System ◽  
Energy Saving Potential ◽  
High Energy Consumption

Based on the system model of hybrid desiccant cooling system using condensing heat as the regeneration source, the solution is given to investigate the system characteristic. The result showed that, when the outdoor air humidity ratio is below 18.5g/kg and indoor dehumidification load is below 1.5kg/h, the energy consumption of this system is lower than the enthalpy recovery air-conditioning system. If not, due to the high energy consumption of electrical heating, the desiccant wheel using condensing heat and electrical heat is not suitable for the humid areas.

Experimental Study on a Hybrid Desiccant Dehumidification and Air Conditioning System

2005 ◽  
Vol 128 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Li Yong ◽  
K. Sumathy ◽  
Y. J. Dai ◽  
J. H. Zhong ◽  
R. Z. Wang
Keyword(s):  
Air Conditioning ◽  
Experimental Tests ◽  
Electrical Energy ◽  
Primary Energy ◽  
Coefficient Of Performance ◽  
Air Flow Rate ◽  
Energy Usage ◽  
Humidity Ratio ◽  
Air Conditioning System ◽  
Air Conditioning Systems

This paper presents the experimental tests on hybrid desiccant dehumidification and air conditioning systems. Experimental tests are carried out with LiCl desiccant at typical operative ranges for air conditioning applications, particularly for high humid regions like Hong Kong. Results are reported in terms of coefficient of performance (COP) based on primary energy usage and electrical energy usage, respectively. Experiments have demonstrated consistent reduction in humidity ratio satisfying the sensible as well as latent load through a respective subsystem and thereby resulting in a higher COP based on primary energy usage. Also, results show that the regeneration temperature as well as process air flow rate have a significant role on the system performance. It is found that the hybrid system can achieve a higher part load performance, and hence can assure of its effective operation all year around in hot humid regions.

Performance Analysis of Heat Pipe Heat Exchanger for Solar Hybrid Desiccant Air-Conditioning System

2015 ◽  
Vol 1115 ◽  
pp. 488-493
Author(s):  
Zuraini Mohd Enggsa ◽  
Arfidian Rachman ◽  
Lisa Nesti ◽  
Sohif Mat ◽  
Kamaruzzaman Sopian
Keyword(s):  
Heat Exchanger ◽  
Heat Pipe ◽  
Air Conditioning ◽  
Cooling System ◽  
Energy Performance ◽  
Coefficient Of Performance ◽  
Air Conditioning System ◽  
External Power ◽  
Set Up ◽  
Pipe Heat

This paper reports the development of a novel solar hybrid desiccant cooling system with heat pipe heat exchanger (HPHE). The aim is to achieve higher efficiency to reduce the use of electricity by utilizing the desiccant dehumidification system to remove latent load, while the vapour-compression and heat pipe heat exchanger meet the sensible load. Novelty comes as the heat pipe heat exchanger in the system operates efficiently without external power. Experimental set-up has been built by combining the rotary desiccant wheel, heat pipe heat exchanger with a compressive cooling system. Tests are carried out at typical operative ranges for air-conditioning applications, specifically for high hot and humid locations in Bangi, Malaysia. Acetone is used as refrigerant in the HPHE. Performance of HPHE are tested and proven to have direct impact on Coefficient of performance (COP). The results shows good performance of heat pipe heat exchanger efficiency with average efficiency and capacity of 0.65 and 2kw respectively. It is found that the hybrid system can achieve a higher energy performance in hot humid regions.

Sign in / Sign up

Export Citation Format

Share Document