Review on Evaporative Cooling Systems

Poultry are one of the most vulnerable species of its kind once the temperature-humidity nexus is explored. This is so because the broilers lack sweat glands as compared to humans and undergo panting process to mitigate their latent heat (moisture produced in the body) in the air. As a result, moisture production inside poultry house needs to be maintained to avoid any serious health and welfare complications. Several strategies such as compressor-based air-conditioning systems have been implemented worldwide to attenuate the heat stress in poultry, but these are not economical. Therefore, this study focuses on the development of low-cost and environmentally friendly improved evaporative cooling systems (DEC, IEC, MEC) from the viewpoint of heat stress in poultry houses. Thermodynamic analysis of these systems was carried out for the climatic conditions of Multan, Pakistan. The results appreciably controlled the environmental conditions which showed that for the months of April, May, and June, the decrease in temperature by direct evaporative cooling (DEC), indirect evaporative cooling (IEC), and Maisotsenko-Cycle evaporative cooling (MEC) systems is 7–10 °C, 5–6.5 °C, and 9.5–12 °C, respectively. In case of July, August, and September, the decrease in temperature by DEC, IEC, and MEC systems is 5.5–7 °C, 3.5–4.5 °C, and 7–7.5 °C, respectively. In addition, drop in temperature-humidity index (THI) values by DEC, IEC, and MEC is 3.5–9 °C, 3–7 °C, and 5.5–10 °C, respectively for all months. Optimum temperature and relative humidity conditions are determined for poultry birds and thereby, systems’ performance is thermodynamically evaluated for poultry farms from the viewpoint of THI, temperature-humidity-velocity index (THVI), and thermal exposure time (ET). From the analysis, it is concluded that MEC system performed relatively better than others due to its ability of dew-point cooling and achieved THI threshold limit with reasonable temperature and humidity indexes.

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Performance Characteristics of Solid-Desiccant Evaporative Cooling Systems

Energies ◽

10.3390/en11102574 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2574 ◽

Cited By ~ 4

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.

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Calculation of Water Evaporative Cooling Systems in Animal Husbandry

Machinery and Equipment for Rural Area ◽

10.33267/2072-9642-2020-11-35-38 ◽

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.

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A review of desiccant evaporative cooling systems in hot and humid climates

Advances in Building Energy Research ◽

10.1080/17512549.2018.1508364 ◽

2018 ◽

pp. 1-42 ◽

Cited By ~ 2

Author(s):

Ismanizam Abd Manaf ◽

Faisal Durrani ◽

Mahroo Eftekhari

Keyword(s):

Evaporative Cooling ◽

Cooling Systems ◽

Hot And Humid Climates

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Impact of integrated hot water cooling and desiccant-assisted evaporative cooling systems on energy savings in a data center

Energy ◽

10.1016/j.energy.2014.10.023 ◽

2014 ◽

Vol 78 ◽

pp. 384-396 ◽

Cited By ~ 20

Author(s):

Min-Hwi Kim ◽

Sang-Woo Ham ◽

Jun-Seok Park ◽

Jae-Weon Jeong

Keyword(s):

Data Center ◽

Energy Savings ◽

Evaporative Cooling ◽

Hot Water ◽

Water Cooling ◽

Cooling Systems

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The Use of Ejector Refrigeration Systems for Turbine Inlet Air Cooling: A Thermodynamic and CFD Study

ASME 2007 Energy Sustainability Conference ◽

10.1115/es2007-36044 ◽

2007 ◽

Cited By ~ 1

Author(s):

Hany A. Al-Ansary

Keyword(s):

Power Consumption ◽

Power Output ◽

Waste Heat ◽

Evaporative Cooling ◽

Published Data ◽

Air Cooling ◽

Refrigeration System ◽

Compressor Blades ◽

Cooling Systems ◽

Turbine Inlet

Cooling turbine inlet air is a proven method of increasing turbine power output, especially during peak summer demand. It is estimated that turbine power output can increase by as much as 0.7% for every 1°C drop in inlet air temperature. Two inlet air cooling systems are widely used: evaporative cooling systems and chiller systems. Evaporative cooling is economical and uncomplicated, but its efficiency can significantly drop if the relative humidity is high. There is also a potential for excessive wear of compressor blades if water droplets are carried into the compressor section. On the other hand, chiller systems have the advantage of being independent of humidity and do not have the potential to cause damage to compressor blades. However, chiller systems consume power and cause a larger pressure drop than evaporative coolers. In this work, the possibility of using an ejector refrigeration system to cool turbine inlet air is explored. These systems are low-maintenance, fluid-driven, heat-operated devices that can use part of the turbine exhaust flow as the heat source for running the cycle. These systems require only pump power to feed liquid refrigerant to the vapor generator, making the power consumption potentially lower than conventional chiller systems. Using thermodynamic analysis, this paper compares the performance of ejector refrigeration systems with that of chiller systems based primarily on their power consumption. Performance characteristics for the ejector system are obtained through a CFD model that uses a real-gas model for R-134a. Published data on the performance of a commercial gas turbine is also considered. The power consumption of ejector refrigeration systems is found to be significantly smaller than that of vapor compression systems, with savings ranging from 19% to 80%. Power consumption is also found to be small compared to the boost in turbine power that is obtained. The percentage of waste heat needed to operate the ejector refrigeration system is found to be generally less than 25%.

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