The limitations of the evaporative cooling capability are analyzed and formulated in terms of the characteristic dimensions involving the temperature ratio, the power gain ratio pgr, thermal efficiency change, and humidity ratio. Pdf performance investigation of evaporative cooling. Pdf performance investigation of evaporative cooling pads. The concepts of trombe wall, solarium, evaporative cooling, ventilation, radiative cooling, wind tower, earth air heat exchanger, roof pond, solar shading for buildings, and building. The limitations of the evaporative cooling capability are analyzed and formulated in terms of the characteristic dimensions involving the temperature ratio, the power gain ratio pgr, thermal efficiency. The temperature of dry air can be dropped significantly through the phase transition of liquid water to water vapor, which requires much less energy than refrigeration. A new approach to analysis and optimization of evaporative cooling system i. This paper aims to investigate the evaporative cooling limitations of compressor intakeair for improving the performance of gas turbine power plants. This type of evaporative coolers combine indirect with direct evaporative cooling. What are the advantages and disadvantages of evaporative. Evaporative cooling is an energy efficient and environmentally friendly air conditioning technology. Indirect evaporative cooling works on the same principle as direct evaporative cooling lowering air temperature by causing water to evaporate. Evaporative cooling occurs when air, that is not too humid, passes over a wet. Performance evaluation of alternative evaporative cooling media.
Direct evaporative cooling is an adiabatic process where the dry bulb temperature is lowered without changing the amount of heat idec dec dec idec in the air. Performance evaluation of alternative evaporative cooling. One of the most energyintensive processes in the ventilation and airconditioning is the process of air cooling. According to the literature published so far, most of the researcher hold view that the iecs are suitable for. Oxygen 21% nitrogen 78% different gases 0,9% carbonic gas 0,03% water vapour 0,05 1,50% psychometrics. Pdf a new mathematical model of a mechanical draft cooling tower performance has been developed.
The primary responsibility of a business man is to provide the secure and comfortable feeling to the clients who visit their office. Theoretical performance analysis of direct evaporative cooler in hot and dry climates ibrahim u. Although the analytical solution compares well with previous literature data, it does not account for the effect of the evaporative cooling. Nero, the emperor, was using ice for cooling beverages.
Modeling, indirect evaporating coolers, thermal comfort, performance. Different types of evaporative cooler have been reported in the literature, some of. We have examine the work related to concept of evaporative cooling published in referred journals. The main difference with an indirect system is that a heat exchanger is used to cool the air supplied to. The process of evaporation naturally lowers ambient air temperatures. Evaporative cooling is a physical phenomenon in which evaporation of a liquid, typically into surrounding air, cools an object or a liquid in contact with it. Study, design and analysis of two stages evaporative cooling system prof. The following texts are the property of their respective authors and we thank them for giving us the opportunity to share for free to students, teachers and users of the web their texts will used only for. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Analysis of the effects of evaporative cooling on the. A short presentation about the definition of evaporative cooling and how it compares to traditional air conditioning. This simple, yet most efficient, law of nature has been used by humans for comfort cooling systems since the days of ancient egypt and the persian empire. Cooling air temperatures that can be achieved by a direct evaporative cooler at various outdoor conditions image courtesy of calcsplus. The use of evaporative cooling is another application of.
Experimental analysis of cellulose cooling pads used in. Biggest problem facing the indirect evaporative cooling iec technology lies in its high level of dependency to ambient air condition. Earth air pipe heat exchanger eaphe and solar chimney sc. This is accomplished by passing air inside a heat exchanger that is cooled by evaporation on the outside. Evaporative cooling uses the fact that water will absorb a relatively large amount of heat in. Hence, a detailed literature survey has been made on the various studies carried out by the researchers on the different passive cooling techniques, free cooling potential.
During the process of perspiration, it absorbs heat to cool the body. Aug 27, 2009 a short presentation about the definition of evaporative cooling and how it compares to traditional air conditioning. This evaporative cooling design guidelines manual for new mexico schools and commercial. Further, the east indians were able to produce refrigeration by dissolving salt in water as early as 4 th century a. Experimental study of cooling tower performance using. Performance analysis of an indirect evaporative cooling. Evaporative cooling an overview sciencedirect topics. His theory of adiabatic saturation and the standard psychrometric chart are its roots. One must know them to understand the operation of evaporative coolers. Pdf evaporative cooling of water in a mechanical draft cooling tower. The results obtained for relative humidity from the greenhouses with different types of evaporative cooling pads, as well as for the conditions outside the greenhouses, at 8 am are shown in table 2 and fig. Evaporative cooling differs from typical air conditioning systems, which use vaporcompression or absorption refrigeration cycles.
Precooling the air by using evaporative cooling increased the cop from 6. This cools the air by extracting from it the latent heat of vaporization and the fan circulates the cooled air though the building. Its material is chemically impregnated with special compounds to prevent rot and ensure a long service life. A general mathematical model of evaporative cooling devices 6. To evaporate one gallon of water requires almost 8,700 btus of heat. Limitations of inlet air evaporative cooling system for. A cooling tower is a heatrejection device, which discharges warm air from the cooling tower to the atmosphere through the cooling of water. Evaporative cooling is based on the thermodynamics of evaporation of water, i. Three different types of evaporative cooling pads were used, namely. In this paper different cooling pads have been studied. There are two basic types of evaporative air coolers eacs. When warm, dry unsaturated air is pulled through a watersoaked pad, water is evaporated and is absorbed as water vapor into the air. The use of evaporative cooling is another application of refrigeration used olden days. An evaporative cooler also swamp cooler, swamp box, desert cooler and wet air cooler is a device that cools air through the evaporation of water.
Stoxstell ii unit 16 condensers flashcards quizlet. Parker hannifin corporation precision cooling business. The analysis of variance showed that there were significant differences p 0. Theory qun chena,b, kangding yanga, moran wangc, ning panb, zengyuan guoa akey laboratory for thermal science and power engineering of ministry of education, department of engineering mechanics, tsinghua university, beijing 84, china b biological and agricultural. This adiabatic cooling process is also used to create the chilled water that feeds our indirect evaporative cooling coil. In case of cabinet type evaporative coolers, the type of pad material. For better human comfort, cooling of living or work environment is vital in tropical climates. Evaluation of evaporative cooling systems in industrial buildings article pdf available in international journal of heat and technology 333. The theory of direct evaporative cooling owes much to dr. Traditional systems based on the compressor cycle consume a lot of energy. Evaporative cooling systems use the same principle as perspiration to provide cooling for machinery and buildings.
Therefore, this paper intends to present a comprehensive summary on them. Study, design and analysis of two stages evaporative. In maisotsenko cycle both the direct evaporative cooling and indirect evaporative cooling is couple together. Evaporative cooling uses the fact that water will absorb a. A thorough search of the current literature showed that there were many studies on the. An evaporative cooler has a fan which blows air through a wetted pad, where water evaporates into the air. Evaporative cooling 3 introduction to the evaporative cooling system for easily understanding the evaporative cooling process you shall know the following basic concepts. Review of passive heatingcooling systems of buildings. Install on the ground or wall, rather than the roof, in order to make maintenance easier for the homeowner. Furnish proof satisfactory to the owner or his representative, of.
Duan, zhiyin 2011 investigation of a novel dew point. Bac evaporative condensers models cxv, cxvt, vc2, vxmc, vc1, vc1c, vcl brochure. Course contents evaporative coolers, often called swamp coolers, are cooling systems that use only water and a blower to circulate air. The driving force of either direct or indirect evaporative cooling is the temperature difference between the drybulb table 1 a general comparison between the currently available air conditioning systems. Ijsrd international journal for scientific research. These heat and mass transfer devices are based on the evaporative cooling of water in contact with ambient air. Overview all internal combustion engines are equipped with cooling and lubricating systems that work in conjunction with each other to promote efficient engine operation and performance. Theoretical efficiency of 100% can be realized when dry bulb.
They claimed that evaporative cooling is more efficient where the climate is hot. Taufiq et al 2007 have conducted an energy analysis of. It is not successful in the areas where the dampness is high. The following texts are the property of their respective authors and we thank them for giving us the opportunity to share for free to students, teachers and users of the web their texts will used only for illustrative educational and scientific purposes only. Evaporative cooling occurs when air, that is not too humid, passes over a wet surface. Nowadays, there are two types of evaporative cooling. Evaporative cooling design guidelines ced engineering. This paper is an attempt to theoretically analyse the performance of direct evaporative cooler in hot and dry climate with kano being the study area. For evaporative cooling, this heat is taken from the air, cooling it as it evaporates. Jul 02, 2014 drawbacks of evaporating cooling system. Experimental study on two type of indirect evaporative cooling heat. View evaporative cooling research papers on academia.
An investigation of indirect evaporative coolers, iec with respect to. Evaporative cooling design guidelines cedengineering. An experimental performance investigation of evaporative cooling pads of different materials based on weather data of ahmedabad, india has been carried out. Evaporative cooling evaporative cooling is a very efficient means of heat dissipation, as one litre evaporated sweat removes 672 wh from the body at a temperature of 35 c. Researches carried out till date in evaporative air cooling process focus mainly on reducing the dry bulb temperature of the incoming air. International journal of engineering research and general. Evaporative cooler engineering specification 598 1. Cooling through evaporation is the natural occurrence.
The following is an example of how wetbulb temperature impacts an evaporative coolers cooling ability. The following table 1 from manufacturers literature can be used to estimate leaving. Theory qun chena,b, kangding yanga, moran wangc, ning panb, zengyuan guoa akey laboratory for thermal science and power engineering of ministry of education, department of engineering mechanics, tsinghua university, beijing 84, china. Effectiveness of evaporative cooling weve all walked through water misters on hot summer days and immediately felt the cooling effect. At the point when considering evaporative cooling, one ought to figure out the wet knob and dry globule temperatures of the region. What are the advantages and disadvantages of evaporative cooling.
Bac evaporative condensers models cxv, cxvt, vc2, vxmc. Student 2assistant professor 1,2shri sad vidya mandal institute of technology, bharuch392001, gujarat, india abstractthis paper aims to improve the performance of. Research and application of evaporative cooling in china have been very fruitful. It will consist of the component parts as listed in the following sections. The most common example in human is the process of perspiration.
The main disadvantage of this kind of particular cooling is that it is only applicable in dry atmospheres. Performance analysis of an indirect evaporative cooling system using m cycle devang s. This phase change requires energy, which is called latent heat of evaporation this is the energy required to change a substance from liquid phase to the gaseous one without temperature change. A new approach to analysis and optimization of evaporative. This system complements direct evaporative cooling, as it consumes low energy to provide cold water, and is able to fulfil the comfort conditions, whereas direct.
Eaphe, energy, evaporative cooling cavity, passive cooling, solar chimney, thermal energy 1. In the hvac industry, the term cooling tower is used to describe both open and. Experimental study of cooling tower performance using ceramic. Evaporative cooling system for storage of fruits and vegetables a. Evaporative cooling, effectiveness, performance, energy saving. A concept of an evaporative cooling utilized with the help of maisotsenko cycle. The primary idea of the indirect evaporative coolers is cooling by decreasing air sensible heat without changing its humidity, which is a distinctive advantage over dec systems. Introduction cooling towers are used for cooling large amounts of water in chemical industry, thermal power plants, nuclear power plants and petroleum industry. Theory and basic principle of evaporative cooling system.
A general mathematical model of evaporative cooling devices. They measured several thermal parameters such as relative humidity rh, dry and wet bulb temperature to evaluate the effect of evaporative cooling on cop. Research and application of evaporative cooling in china. Direct evaporative cooling dec keeps the primary product air in direct contact with water, which causes evaporation of the water and so the reduction of temperature. The evaporative cooling module shall be selfcontained. A schematic illustration and photo of the used experimental apparatus are shown in fig. Performance evaluation of three different types of local. Types of evaporative cooling evaporative cooling works by employing waters large. Oct 05, 2015 this paper aims to investigate the evaporative cooling limitations of compressor intakeair for improving the performance of gas turbine power plants. Sources of literature numerous articles dealing with theory and working of evaporative cooling have been published over last 5 years, but topic is still under considerable development.
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