scholarly journals Investigation of Desiccant and Evaporative Cooling Systems for Animal Air-Conditioning

2020 ◽  
Author(s):  
Muhammad Sultan ◽  
Hassan Niaz ◽  
Takahiko Miyazaki
Keyword(s):  
Air Conditioning ◽  
Evaporative Cooling ◽  
Cooling Systems

scholarly journals Performance Characteristics of Solid-Desiccant Evaporative Cooling Systems

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2574 ◽  
Author(s):  
Ramadas Narayanan ◽  
Edward Halawa ◽  
Sanjeev Jain
Keyword(s):  
Air Conditioning ◽  
Natural Ventilation ◽  
Waste Heat ◽  
Numerical Study ◽  
Evaporative Cooling ◽  
Peak Load ◽  
Dew Point ◽  
Low Grade ◽  
Subtropical Climate ◽  
Cooling Systems

Air conditioning accounts for up to 50% of energy use in buildings. Increased air-conditioning-system installations not only increase total energy consumption but also raise peak load demand. Desiccant evaporative cooling systems use low-grade thermal energy, such as solar energy and waste heat, instead of electricity to provide thermal comfort. This system can potentially lead to significant energy saving, reduction in carbon emissions, and it has a low dew-point operation and large capacity range. Their light weight, simplicity of design, and close-to-atmospheric operation make them easy to maintain. This paper evaluates the applicability of this technology to the climatic conditions of Brisbane, Queensland, Australia, specifically for the residential sector. Given the subtropical climate of Brisbane, where humidity levels are not excessively high during cooling periods, the numerical study shows that such a system can be a potential alternative to conventional compression-based air-conditioning systems. Nevertheless, the installation of such a system in Brisbane’s climate zone requires careful design, proper selection of components, and a cheap heat source for regeneration. The paper also discusses the economy-cycle options for this system in such a climate and compares its effectiveness to natural ventilation.

scholarly journals Calculation of Water Evaporative Cooling Systems in Animal Husbandry

2020 ◽  
pp. 35-38
Author(s):  
N.N. Novikov ◽  
Keyword(s):  
Air Conditioning ◽  
Evaporation Rate ◽  
Evaporative Cooling ◽  
Animal Husbandry ◽  
Water Evaporation ◽  
Cooling Systems ◽  
Temperature And Humidity ◽  
Hot Weather ◽  
Livestock Building ◽  
Air Exchange

A method for calculating the parameters of the microclimate in a livestock building using water-evaporative air conditioning is described. It makes it possible to choose a rational temperature and humidity conditions for a room in hot weather, calculate the required air exchange, water evaporation rate and select the appropriate equipment.

Solar Assisted Desiccant Cooling Simulation for Different Climate Zones

2011 ◽  
Author(s):  
Wendell Concina ◽  
Suresh Sadineni ◽  
Robert Boehm
Keyword(s):  
Air Conditioning ◽  
Cooling System ◽  
Evaporative Cooling ◽  
The United States ◽  
Economic Benefits ◽  
Climatic Conditions ◽  
Hot Water ◽  
Low Grade ◽  
Cooling Systems ◽  
Climate Zones

Evaporative cooling is among the most cost effective methods of air conditioning, but is less efficient in humid climates. An evaporative system coupled with a desiccant wheel can operate effectively in broader climatic conditions. These cooling systems can substitute traditional vapor compression air conditioning systems as they involve environmentally friendly cooling processes with reduced electricity demand (which is commonly generated from fossil fuels) along with no harmful CFC based refrigerant usage. Furthermore, direct utilization of low grade energy sources such as solar thermal energy or flue gas heat can drive the desiccant regeneration process, thus providing economic benefits. This study presents the results of simulations of desiccant cooling system performance for different climate zones of the United States. Solar assisted desiccant air conditioning is particularly useful where there are abundant solar resources with high temperature and humidity levels. Building energy simulations determined cooling energy requirements for the building. Simulation of an evacuated solar hot water collector model provided the heat energy available for regeneration of the desiccant. Solid desiccant of common material such as silica gel used in a rotary wheel is simulated using established validated computer models; this is coupled with evaporative cooling. Transients of the overall system for different cooling loads and solar radiation levels are presented. Finally, feasibility studies of the desiccant cooling systems are presented in comparison with traditional cooling system. Further analysis of the data presents optimization opportunities. Energy savings were achieved in all climatic conditions with decreased effectiveness in more humid conditions.

scholarly journals Temperature and Humidity Control for the Next Generation Greenhouses: Overview of Desiccant and Evaporative Cooling Systems

2021 ◽  
Author(s):  
Muhammad Sultan ◽  
Hadeed Ashraf ◽  
Takahiko Miyazaki ◽  
Redmond R. Shamshiri ◽  
Ibrahim A. Hameed
Keyword(s):  
Molecular Sieves ◽  
Air Conditioning ◽  
Activated Carbons ◽  
Evaporative Cooling ◽  
Next Generation ◽  
Cooling Systems ◽  
Humidity Control ◽  
Climatic Regions ◽  
Multi Stage ◽  
Temperature And Humidity

Temperature and humidity control are crucial in next generation greenhouses. Plants require optimum temperature/humidity and vapor pressure deficit conditions inside the greenhouse for optimum yield. In this regard, an air-conditioning system could provide the required conditions in harsh climatic regions. In this study, the authors have summarized their published work on different desiccant and evaporative cooling options for greenhouse air-conditioning. The direct, indirect, and Maisotsenko cycle evaporative cooling systems, and multi-stage evaporative cooling systems have been summarized in this study. Different desiccant materials i.e., silica-gels, activated carbons (powder and fiber), polymer sorbents, and metal organic frameworks have also been summarized in this study along with different desiccant air-conditioning options. However, different high-performance zeolites and molecular sieves are extensively studied in literature. The authors conclude that solar operated desiccant based evaporative cooling systems could be an alternate option for next generation greenhouse air-conditioning.

scholarly journals Energy - Saving Potential of Evaporative Cooling System for Building Application - A Review

2020 ◽  
pp. 14-17
Keyword(s):  
Air Conditioning ◽  
Cooling System ◽  
Evaporative Cooling ◽  
Cooling Systems ◽  
Energy Saving Potential ◽  
The Earth ◽  
Direct Evaporative Cooling ◽  
Evaporative Cooling System ◽  
Air Conditioning Systems ◽  
Vapour Compression

The function of air conditioning systems has seen impressive development over the most recent couple of decades everywhere throughout the world, particularly in commercial buildings in ensuring the occupant thermal comfort. All the same, it is followed to have bad effects on the earth as well as increased power consumption in buildings. Hence, there has been extensive research to recognize options, in contrast to conventional vapour compression air conditioning systems. This account intends to review the ongoing improvements concerning evaporative cooling advancements that might give adequate cooling comfort, reduce environmental impact and lower energy consumption in buildings. Researches have done as on date in evaporative cooling systems centre predominantly around mainly on drawing down the dry bulb temperature of the incoming air. The theoretical efficiency of 100% can be achieved when the room dry bulb temperature is equal to the wet-bulb temperature of the outside atmospheric air. A wide literature review has been carried out and mapped out the best evaporative cooling systems. The review covers direct evaporative cooling, indirect evaporative cooling, and combined direct-indirect cooling systems.

scholarly journals A Study on Thermal Effectiveness of Multi-Stages Evaporative Air Cooling

2020 ◽  
Vol 8 (2) ◽  
pp. 1-14
Author(s):  
Alaa R. Al-Badri ◽  
Zahraa Mohsin Farhan
Keyword(s):  
Air Temperature ◽  
System Performance ◽  
Air Conditioning ◽  
Evaporative Cooling ◽  
Experimental Tests ◽  
Weather Conditions ◽  
Air Cooling ◽  
Air Velocity ◽  
Cooling Systems ◽  
Continuous Increase

The air conditioning system performance is significantly affected by temperature rise which causes continuous increase in electricity consumption and pollution problems to environment. Evaporative cooling systems are characterized by their low energy consumption so that they represent successful potential alternatives to traditional vapor compression air conditioning systems. This study investigates the performance of multi-stages evaporative cooling systems experimentally and theoretically. The experimental set-up is mainly composed of two parts: indirect unit to decrease the air temperature and direct unit to moisturize the air. The system is installed and equipped with temperatures, humidity, and air velocity sensors. The experimental tests were run continuously to monitor the system performance at various weather conditions between  to  in June and July months. A mathematical model for the system components was developed and implemented in the Engineering Equation Solver (EES) program to simulate the performance of multi-stages evaporative cooling systems. The results showed that the heat flux  increases with the increase in the Reynolds number Re of inlet air, velocity fraction  extracted air for sensible cooling, air temperature at the product-in , air velocity at the product-in , and the adiabatic efficiency . But, it is decreasing with increasing the spacing between the heat exchanger plates  and the relative humidity at the product-in . Optimum performance was obtained with very small space between plates which was bout 5mm. Good agreement have been shown between experimental and predicted data, where the  results. Uncertainty of experimental data was within the range 4.14 to 6.15.

scholarly journals Artificial Intelligence for the Prediction of the Thermal Performance of Evaporative Cooling Systems

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3946
Author(s):  
Hafiz M. Asfahan ◽  
Uzair Sajjad ◽  
Muhammad Sultan ◽  
Imtiyaz Hussain ◽  
Khalid Hamid ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Deep Learning ◽  
Thermal Performance ◽  
Air Conditioning ◽  
Learning Algorithm ◽  
Evaporative Cooling ◽  
Cooling Systems ◽  
Ground Truth Data ◽  
Deep Learning Algorithm ◽  
Air Conditioning Systems

The present study reports the development of a deep learning artificial intelligence (AI) model for predicting the thermal performance of evaporative cooling systems, which are widely used for thermal comfort in different applications. The existing, conventional methods for the analysis of evaporation-assisted cooling systems rely on experimental, mathematical, and empirical approaches in order to determine their thermal performance, which limits their applications in diverse and ambient spatiotemporal conditions. The objective of this research was to predict the thermal performance of three evaporation-assisted air-conditioning systems—direct, indirect, and Maisotsenko evaporative cooling systems—by using an AI approach. For this purpose, a deep learning algorithm was developed and lumped hyperparameters were initially chosen. A correlation analysis was performed prior to the development of the AI model in order to identify the input features that could be the most influential for the prediction efficiency. The deep learning algorithm was then optimized to increase the learning rate and predictive accuracy with respect to experimental data by tuning the hyperparameters, such as by manipulating the activation functions, the number of hidden layers, and the neurons in each layer by incorporating optimizers, including Adam and RMsprop. The results confirmed the applicability of the method with an overall value of R2 = 0.987 between the input data and ground-truth data, showing that the most competent model could predict the designated output features (Toutdb, wout, and Eoutair). The suggested method is straightforward and was found to be practical in the evaluation of the thermal performance of deployed air conditioning systems under different conditions. The results supported the hypothesis that the proposed deep learning AI algorithm has the potential to explore the feasibility of the three evaporative cooling systems in dynamic ambient conditions for various agricultural and livestock applications.

New corrosion inhibitors for evaporative cooling systems

2013 ◽  
Vol 44 (1) ◽  
pp. 39-54
Author(s):  
A. Wehlmann ◽  
W. Hater ◽  
F. Wolf ◽  
R. Lunkenheimer ◽  
C. Foret ◽  
...  
Keyword(s):  
Corrosion Inhibitors ◽  
Evaporative Cooling ◽  
Cooling Systems

scholarly journals Evaporative Cooling Options for Building Air-Conditioning: A Comprehensive Study for Climatic Conditions of Multan (Pakistan)

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3061 ◽  
Author(s):  
Shazia Noor ◽  
Hadeed Ashraf ◽  
Muhammad Sultan ◽  
Zahid Mahmood Khan
Keyword(s):  
Thermal Comfort ◽  
Co2 Emissions ◽  
Air Conditioning ◽  
Evaporative Cooling ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Maximum Temperature ◽  
Human Thermal Comfort ◽  
Work Input ◽  
System Configurations

This study provides comprehensive details of evaporative cooling options for building air-conditioning (AC) in Multan (Pakistan). Standalone evaporative cooling and standalone vapor compression AC (VCAC) systems are commonly used in Pakistan. Therefore, seven AC system configurations comprising of direct evaporative cooling (DEC), indirect evaporative cooling (IEC), VCAC, and their possible combinations, are explored for the climatic conditions of Multan. The study aims to explore the optimum AC system configuration for the building AC from the viewpoints of cooling capacity, system performance, energy consumption, and CO2 emissions. A simulation model was designed in DesignBuilder and simulated using EnergyPlus in order to optimize the applicability of the proposed systems. The standalone VCAC and hybrid IEC-VCAC & IEC-DEC-VCAC system configurations could achieve the desired human thermal comfort. The standalone DEC resulted in a maximum COP of 4.5, whereas, it was 2.1 in case of the hybrid IEC-DEC-VCAC system. The hybrid IEC-DEC-VCAC system achieved maximum temperature gradient (21 °C) and relatively less CO2 emissions as compared to standalone VCAC. In addition, it provided maximum cooling capacity (184 kW for work input of 100 kW), which is 85% higher than the standalone DEC system. Furthermore, it achieved neutral to slightly cool human thermal comfort i.e., 0 to −1 predicted mean vote and 30% of predicted percentage dissatisfied. Thus, the study concludes the hybrid IEC-DEC-VCAC as an optimum configuration for building AC in Multan.

Sign in / Sign up

Export Citation Format

Share Document