scholarly journals Investigating Applicability of Evaporative Cooling Systems for Thermal Comfort of Poultry Birds in Pakistan

2020 ◽  
Vol 10 (13) ◽  
pp. 4445
Author(s):  
Hafiz M. U. Raza ◽  
Hadeed Ashraf ◽  
Khawar Shahzad ◽  
Muhammad Sultan ◽  
Takahiko Miyazaki ◽  
...  
Keyword(s):  
Heat Stress ◽  
Thermal Comfort ◽  
Developing Economies ◽  
Low Cost ◽  
Evaporative Cooling ◽  
Ambient Air ◽  
Climatic Conditions ◽  
Maximum Temperature ◽  
Poultry Birds ◽  
The City

In the 21st century, the poultry sector is a vital concern for the developing economies including Pakistan. The summer conditions of the city of Multan (Pakistan) are not comfortable for poultry birds. Conventionally, swamp coolers are used in the poultry sheds/houses of the city, which are not efficient enough, whereas compressor-based systems are not economical. Therefore, this study is aimed to explore a low-cost air-conditioning (AC) option from the viewpoint of heat stress in poultry birds. In this regard, the study investigates the applicability of three evaporative cooling (EC) options, i.e., direct EC (DEC), indirect EC (IEC), and Maisotsenko-cycle EC (MEC). Performance of the EC systems is investigated using wet-bulb effectiveness (WBE) for the climatic conditions of Multan. Heat stress is investigated as a function of poultry weight. Thermal comfort of the poultry birds is calculated in terms of temperature-humidity index (THI) corresponding to the ambient and output conditions. The heat production from the poultry birds is calculated using the Pederson model (available in the literature) at various temperatures. The results indicate a maximum temperature gradient of 10.2 °C (MEC system), 9 °C (DEC system), and 6.5 °C (IEC systems) is achieved. However, in the monsoon/rainfall season, the performance of the EC systems is significantly reduced due to higher relative humidity in ambient air.

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.

scholarly journals Experiments on Energy-Efficient Evaporative Cooling Systems for Poultry Farm Application in Multan (Pakistan)

2021 ◽  
Vol 13 (5) ◽  
pp. 2836
Author(s):  
Khawar Shahzad ◽  
Muhammad Sultan ◽  
Muhammad Bilal ◽  
Hadeed Ashraf ◽  
Muhammad Farooq ◽  
...  
Keyword(s):  
Heat Stress ◽  
Low Cost ◽  
Evaporative Cooling ◽  
Thermal Exposure ◽  
Climatic Conditions ◽  
The Body ◽  
Dew Point ◽  
Sweat Glands ◽  
Cooling Systems ◽  
Humidity Index

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.

scholarly journals Effect of the Evaporative Cooling on the Human Thermal Comfort and Heat Stress in a Greenhouse under Arid Conditions

2013 ◽  
Vol 2013 ◽  
pp. 1-9
Author(s):  
A. M. Abdel-Ghany ◽  
I. M. Al-Helal ◽  
M. R. Shady
Keyword(s):  
Heat Stress ◽  
Thermal Comfort ◽  
Thermal Sensation ◽  
Evaporative Cooling ◽  
Climatic Conditions ◽  
Human Thermal Comfort ◽  
Solar Radiation Flux ◽  
Different Types ◽  
Greenhouse Workers ◽  
Globe Temperature

Thermal sensation and heat stress were evaluated in a plastic greenhouse, with and without evaporative cooling, under arid climatic conditions in Riyadh, Saudi Arabia. Suitable thermal comfort and heat stress scales were selected for the evaluation. Experiments were conducted in hot sunny days to measure the required parameters (i.e., the dry and wet bulb temperatures, globe temperature, natural wet bulb temperature, and solar radiation flux) in the greenhouse. The results showed that in the uncooled greenhouse, workers are exposed to strong heat stress and would feel very hot most of the day time; they are safe from heat stress risk and would feel comfortable during night. An efficient evaporative cooling is necessary during the day to reduce heat stress and to improve the comfort conditions and is not necessary at night. In the cooled greenhouse, workers can do any activity: except at around noon they should follow a proposed working schedule, in which the different types of work were scheduled along the daytimes based on the heat stress value. To avoid heat stress and to provide comfort conditions in the greenhouses, the optimum ranges of relative humidity and air temperature are 48–55% and 24–28°C, respectively.

scholarly journals The influence of the climatology of the semi-arid from Alagoas-Brazil on the raw milk microbiota

2017 ◽  
Vol 3 (1) ◽  
pp. 27
Author(s):  
Ticiano Gomes do Nascimento ◽  
Euridice Farias Falcão ◽  
Maria Cristina Delgado da Silva ◽  
Josicleide Nascimento Oliveira Silvino ◽  
Pierre Barnabé Escodro ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Thermal Comfort ◽  
Vegetation Index ◽  
Raw Milk ◽  
Climatic Conditions ◽  
The State ◽  
Maximum Temperature ◽  
Climatic Data ◽  
Microbiological Analysis ◽  
Semi Arid

This study aimed to evaluate the influence of the climatology of the semi-arid from Alagoas-Brazil on the raw milk microbiota in semi-arid area of the 07 micro-regions of the State of Alagoas of Alagoas, Brazil. The climatic data were extracted from National Institute of Meteorology from the Brazilian government. The raw milk was collected after the dairy cow milking process in 12 small rural associations of the semi-arid from the State of Alagoas, during the 4 seasons and the raw milk was carried out procedures of sampling, transportation and microbiological analysis. A total of 58 samples were counted coliforms at 45°C, <em>Escherichia coli</em> and coagulase-positive <em>Staphylococcus</em>. Only 02 rural associations presented low levels of microbiological contamination, which were located in areas of climatic conditions and parameters of thermal comfort index and vegetation index favorable, but 10 rural associations presented high counting of coliforms at 45°C, <em>Escherichia coli</em>. The climatologic parameters (maximum temperature, atmospheric pressure), bovine comfort thermal index and vegetation index have showed to influence the growth of the coliforms at 45°C and <em>Escherichia coli</em> with high incidence during the summer weather. The precipitation parameter, bovine thermal comfort and vegetation index have displayed to influence coagulase-positive<em> Staphylococcus</em> counting especially during the period between the summer end and the autumn beginning seasons. New Actions, and Rural Education and Health Programs should be implemented as politics of Food Safety. New strategies and programs for dissemination more effective on the risks of transmission of pathogens and Foodborne Diseases are necessary as the part of emergence politics of the health and education areas. Regulatory Actions should be encouraged within the processes that improve the quality control of raw milk as well its bioproducts, with professional assistance relevant in agriculture area.

Commercial Use of Nonmotorized Transport: Evidence from Accra, Ghana

1996 ◽  
Vol 1563 (1) ◽  
pp. 1-7
Author(s):  
Fred Amponsah ◽  
Jeff Turner ◽  
Margaret Grieco ◽  
Andrews Kwablah ◽  
Paul Guitink
Keyword(s):  
World Bank ◽  
Low Income ◽  
Developing Economies ◽  
Low Cost ◽  
Commercial Use ◽  
Small Load ◽  
Transportation Modes ◽  
Mode Of Transport ◽  
The City ◽  
World Bank Project

The traders of Accra, Ghana, continue to make use of hand-pushed and hand-pulled carts for moving their stock across the city. These non-motorized forms of transport play a key role in a low-income economy; developing economies, with their large informal sectors and plentiful supply of petty-trading enterprises, contain a preponderance of enterprises having restricted capital bases, a condition that requires the use of low-cost transportation. The bicycle, although well suited to the small-load requirements of much petty trading, is not regarded as a suitable mode of transport for women, who make up the majority of Ghana's traders. A World Bank project designed to support and promote models of nonmotorized transportation is being implemented. The practices and prospects of the commercial use of nonmotorized transport in Ghana is discussed, the World Bank project that supports and promotes these transportation modes is described, and the appropriateness of nonmotorized transportation modes for developing economies is discussed.

scholarly journals Thermophysics Analysis of Office Buildings with a Temperature–Humidity Coupling Strategy Under Hot-Arid Climatic Conditions

2021 ◽  
Vol 42 (8) ◽  
Author(s):  
Mohammed Bensafi ◽  
Houari Ameur ◽  
Noureddine Kaid ◽  
Siamak Hoseinzadeh ◽  
Saim Memon ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Ambient Air ◽  
Arid Environment ◽  
Considerable Effect ◽  
Climatic Conditions ◽  
Thermal Fields ◽  
Northwestern Region ◽  
Coupling Strategy ◽  
American Society ◽  
The University

AbstractThis study investigates the determining parameters of thermal comfort of office in an arid hot-arid environment of Bechar, located in the northwestern region of Algeria, in which the vertical walls of the room and the roof are subjected to solar irradiations and the floor is considered to be adiabatic. The solar flux is calculated by the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) method. The predicted results are validated against the experimental results of the meteorological station of the ENERGARID research laboratory at the University of Bechar (Algeria). The characteristics of the ambient air flow are performed by using the computational fluid dynamics (CFD) software (Fluent). The flow fields, thermal fields, and humidity are investigated. An elaborated computer program (with Delphi language) is utilized to evaluate the temperature–humidity coupling as the most essential factors of the thermal comfort. A significant impact of dynamic temperatures and humidity on thermal comfort has been observed, especially in this hot-arid environment. Besides, a considerable effect of the flow velocity has been remarked. From the obtained results and to provide the best thermal comfort in such arid regions, the range of air velocity inside the building is recommended to be between 0.2 m·s−1 and 0.3 m·s−1.

scholarly journals What is the most threatening for citizens of a mid-latitude city: cold stress or heat stress?

2021 ◽  
Author(s):  
Sara Top ◽  
Dragan Milošević ◽  
Steven Caluwaerts ◽  
Stevan Savić
Keyword(s):  
Heat Stress ◽  
Cold Stress ◽  
Thermal Comfort ◽  
Heat Wave ◽  
Outdoor Thermal Comfort ◽  
Belgian Society ◽  
Human Thermal Comfort ◽  
Summer Heat ◽  
Heat And Cold Stress ◽  
The City

&lt;p&gt;Both heat and cold waves cause extreme human thermal discomfort and a clear excess in mortality. This shows the importance of knowing the prevailing thermal comfort conditions and how thermal comfort conditions vary in various environments so measures can be taken. Microclimatic and outdoor human thermal comfort conditions are investigated in various built-up and green areas in the city of Ghent (Belgium) using meteorological measurements of six weather stations of the MOCCA (Monitoring the Cities Climate and Atmosphere) network in combination with calculations done by RayMan.&lt;/p&gt;&lt;p&gt;Normal to extreme summer heat wave periods show that dangerous strong heat stress prevails during the daytime periods at all locations. Comparison of thermal comfort during normal and extreme summer heat wave periods showed that heat stress is more extreme when a heat wave is more intense. Overall the urban park in Ghent was the most comfortable location during heat waves since it effectively mitigates heat stress in the city. These results should be taken into account in urban planning and design to keep mid-latitude cities livable.&lt;/p&gt;&lt;p&gt;Further, a one year data series revealed that outdoor cold stress was more apparent during 2017 in the mid-latitude city of Ghent that experiences a mild maritime climate. During spring and summer, both heat stress and cold stress occurred due to the larger diurnal temperature range compared to the other seasons. Even though high Physiological Equivalent Temperatures (PET) were obtained during a heat wave in summer, heat stress did not occur as intensely and as frequently compared to cold stress on annual level. It could thus be stated that outdoors, cold stress is a bigger threat than heat stress. However, one should keep in mind that the study was executed for outdoor thermal heat comfort and that people will take shelter or take measures when feeling uncomfortable. The question is thus rather, how are citizens protected against heat and cold stress? Currently, the Belgian society is better adapted to cold stress since most buildings contain central heating, while air conditioning is not standard. Future projections predict an increase in temperature, causing more occurrence of extreme heat stress, while extreme cold stress will be reduced. Additionally, the urban heat island effect currently has mainly a positive effect on the average annual outdoor thermal comfort conditions, while it will become a negative effect in the warmer future. Measures should thus be taken to reduce the threat of future heat stress.&lt;/p&gt;

scholarly journals Preservation of Postharvest Quality of Leafy Amaranth (Amaranthus spp.) Vegetables Using Evaporative Cooling

2017 ◽  
Vol 2017 ◽  
pp. 1-6
Author(s):  
Jane Ambuko ◽  
F. Wanjiru ◽  
G. N. Chemining’wa ◽  
W. O. Owino ◽  
Eliakim Mwachoni
Keyword(s):  
Vitamin C ◽  
Low Cost ◽  
Evaporative Cooling ◽  
Storage Period ◽  
Ambient Air ◽  
Leafy Vegetables ◽  
Postharvest Quality ◽  
Rapid Decline ◽  
Time Changes

Leafy vegetables are very highly perishable and must be utilized immediately after harvest. Their fast deterioration is attributed to various biological and environmental factors with temperature playing a central role. Evaporative cooling is a low-cost temporary storage technology that offers smallholder vegetable farmers an alternative to expensive cold rooms. The present study sought to determine the effectiveness of evaporative cooling using zero energy brick cooler (ZEBC) and evaporative charcoal cooler (ECC), to preserve the postharvest quality of leafy amaranth vegetables. Freshly harvested vegetables were separated into bundles weighing 300 grams and stored under ZEBC, ECC, and ambient room conditions (control). Real time changes in temperature and relative humidity (RH) as well as changes in quality attributes (physiological weight loss (PWL), wilting index, hue angle, and vitamin C) were determined during the storage period. The temperature difference between the ZEBC and ECC versus the ambient air ranged between 4 and 10°C. Significantly higher RH (80–100%) was recorded in both evaporative cooling chambers. At the end of storage, higher PWL (47.6%) was recorded at ambient room conditions compared to 10.5 and 6.7% under ZEBC and ECC, respectively. A rapid decline in vitamin C (51%) was reported in vegetables stored at ambient room conditions. Overall, there was better vegetable quality preservation under ECC and ZEBC.

Comparative Study of Solar Water Heating Systems - Flat Plate Collector (FPC) with Evacuated Tube Collector

2016 ◽  
Vol 26 ◽  
pp. 76-85 ◽  
Author(s):  
Jefferson Stanley David ◽  
Jayaraman Viveckraj ◽  
Sivamani Seralathan ◽  
K. Varatharajan
Keyword(s):  
Low Cost ◽  
Heating System ◽  
Climatic Conditions ◽  
Maximum Temperature ◽  
Water Heating ◽  
Solar Water Heating ◽  
Solar Water ◽  
The Difference ◽  
Solar Water Heating System ◽  
Flat Plate Collector

Solar energy is one of the alternatives to replace the use of conventional energy sources to heat water for domestic use. This paper focuses on the design and fabrication of a second generation indigenized FPC with locally available low cost material and compares its performance with existing costlier ETC solar water heating system. Readings of FPC and ETC are taken on different days at different time intervals having varied climatic conditions and humidity levels. Analysis of data showed that the rate of temperature rise in ETC is higher than FPC. The maximum temperature reached by these two solar water heating system varies from 2°C to 4°C. The difference between ETC and the indigenized FPC is the time taken to reach the peak temperature. This is due to a better conversion factor and a comparatively low thermal loss factor of ETC. Considering the energy saving involved, as the difference in temperature between FPC and ETC ranges from 0.10°C to 6.80°C, FPC is better suited to heat water for domestic uses given the climatic conditions prevailing in Coimbatore city, India.

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