Assessment Of Evaporative Cooling System For Storage Of .
International Journal of Science and Research (IJSR)ISSN (Online): 2319-7064Index Copernicus Value (2013): 6.14 Impact Factor (2014): 5.611Assessment of Evaporative Cooling System forStorage of VegetablesB.G Jahun1, S.A. Abdulkadir2, S. M. Musa3, Huzaifa Umar41, 3, 4Agricultural and Bioresource Engineering Department, Abubakar Tafawa Balewa University, Bauchi State, Nigeria2Agricultural and Bio-environmental Engineering Department, Adamawa State Polytechnic Yola, Adamawa State, NigeriaAbstract:An evaporative cooler was developed and assessed with locally available materials. The materials were outsourced andconstructed locally within the study area. A daily monitoring of temperature and relative humidity for both ambient and the cooler wererecorded using the wet bulb and dry bulb thermometer and digital humidity–temperature meter. The weight loss was measured using adigital weighing balance. The performance of the evaporative cooler was evaluated in terms of drops in temperature, weight loss andincreased relative humidity and evaporative effectiveness. From the results it showed that the evaporative cooler can lessen the dailymaximum ambient temperature, the average temperature inside the cooling chamber varied from 20 to 23.5 0C while the ambient airtemperature varied from 25 to 280C for tomatoes and an average of 20.5 to 26.50C inside the cabinet while the ambient air temperaturewas from 28 to 30.50C for hot pepper. The mean relative humidity of the cabinet during the period of the experiment was about 51 to93%, respectively, while the mean relative humidity of the ambient environment was from 47 to 58% for tomatoes, and the mean relativehumidity for hot pepper was from 49 to 95% of the cabinet and the mean relative humidity of ambient was from 47 to 57%. Theeffectiveness of the evaporative cooler was higher during the day between the periods of 12 -14 hrs.local time when observed. Theevaporative cooler was able to preserve freshly harvested tomato and hot pepper for 8 days before color changes and mold spottingappeared and the weight was drastically reduced.Keywords: Evaporative Cooler, Temperature, Relative humidity, Weight lossthe produce will be available for longer periods; this wouldreduce fluctuation in market supply and prices [5].1. IntroductionVegetables are vital agricultural products for humanconsumption worldwide. They are rich in vitamins andminerals such as carotene (pro-vitamin A), ascorbic acid,riboflavin, iron, iodine, calcium etc. [1].Vegetables are the fresh and edible portions of herbaceousplants. They are important food and highly beneficial for themaintenance of health and prevention of diseases. Theycontain valued food ingredients which can be successfullyutilized to build up and repair the body. Vegetables arevaluable in maintaining an alkaline reserve of the body. Theyare valued mainly for their high carbohydrate, vitamin andmineral contents from different kinds of vegetables [2].The importance of fruits and vegetables is that they providevitamins and other nutrients that help for proper function ofthe body. Fruits and vegetables are essential building blocksof any diet, not only they are loaded with vitamins andminerals which are essential for healthy living, but they alsogive satisfaction as part of the balanced diet [3].Vegetables are generally regarded as an essential herbaceousplant with high moisture content in their fresh forms. Theypossess considerable quantities of vitamins A, B, C, D, E andK, which help in protecting the body against diseases andcontribute in no small measure to good health [3]. Hence,they provide maximum vitamins when consumed fresh.Evaporative cooling has been found to be an efficient andeconomical means of reducing temperatures and increasinghumidity in an enclosure where the humidity iscomparatively low [4]. Minimizing deteriorative reactions infruit and vegetables enhances their shelf lives, implying thatPaper ID: NOV152974Fruits and vegetables are highly perishable commodities thatcannot be kept for long period of time due to their perishableand seasonal nature. It is therefore important that they arepreserved in season when obtainable in order to ensure theiravailability throughout the year with their nutritional valuestill retained [6]. In addition, preservation of fruits andvegetables is of great importance because it makes provisionfor delayed use, value addition and eliminates wastage [7].Low-temperature handling and storage have been describedas the most important physical method for post-harvest losscontrol [8]. The temperature of the surrounding air andproduce can be reduced by forced air cooling, hydro-cooling,vacuum cooling, and adiabatic cooling [9].Fruits and vegetables are highly perishable commodities thatcannot be kept for a long period due to their perishablenature and, therefore, presents storage difficulties [10]. Thisstudy is to assess the storage of fresh fruits and vegetablesto reduce some of the postharvest losses and raise the valueat the glut period.Evaporative cooling is a well-known system to cool theenvironment. This is an adiabatic process, in which ambientair is cooled as a result of transferring its sensible heat to theevaporated water carried with the air. In the evaporativecooled structure, the maximum advantage of the naturalenvironment is taken for lowering down the temperature ofoutside ambient air to a considerable low level. Theevaporative cooling storage system is easy to operate,efficient and affordable most especially for peasant farmersin developing countries like Nigeria where other methods ofpreservation are quite expensive and unaffordable [11].Volume 5 Issue 1, January 2016www.ijsr.netLicensed Under Creative Commons Attribution CC BY1197
International Journal of Science and Research (IJSR)ISSN (Online): 2319-7064Index Copernicus Value (2013): 6.14 Impact Factor (2014): 5.611Evaporative cooling storage structure (ECSS) is a doublewall structure having space between the walls which is filledwith porous water-absorbing materials called pads [12-14].These pads are kept constantly moist by applying water.When unsaturated air passes through a soaked pad, transferof mass and heat takes place and the energy for theevaporation process comes from the air stream. Evaporativecooling is an adiabatic process occurring at constant enthalpy[15, 16]. This is the most economical way of reducing thetemperature by humidifying the air. It has many advantagesover refrigeration system, as it does not use refrigerant so itis environmental friendly (reduces CO2). It does not makenoise as there is no moving part. It does not use electricity soits saves energy. It does not require high initial investment aswell as operational cost in design and maintenance. It can beconstructed with locally available materials in remote areasand most importantly, it is eco-friendly as it does not needchlorofluorocarbons [17, 18]. Evaporation of moisture fromvegetables causes wilting and shriveling resulting in weightloss. The process of evaporative cooling is an adiabaticexchange of heat when ambient air is passed through asaturated surface to obtain low temperature and highhumidity, which are desirable for extending the storage lifeof vegetables [19].2.Material and Methods2.1MaterialsThe following materials were selected: Wood (Mahoganyand Akwamari), Jute bag, Wire mesh or gauzes wire,Aluminum sheet, Glue, Nail, Thermometer (wet bulb and drybulb), digital weighing balance, and calibrated bucket. Whilechoosing the materials the following factors were consideredas, availability of the materials, suitability of the materialunder working conditions, cost of materials, strength of thematerials, hardness of the materials, malleability, toughnessand reaction of the materials with food and water [20].2.2Description of the SystemThe storage chamber consists of three trays in the form ofdrawers where the fruits and vegetables are stored. The trayswere constructed from cross netted wire materials (wiremesh) with wooden edges of the storage chamber beingaccessible from the side of the structure. The structuralframework of the system is covered with jute bag whichencloses the cooling medium. Water troughs are at the topand bottom of the structure in order to provide water for thecontinuous wetting of the jute bag by gravity and capillaryaction. The water troughs were constructed from aluminumsheet. The entire structure sits inside the bottom water troughto facilitate water movement through the jute bag and also tocollect water that flows by gravity through the jute bag fromthe upper water trough as reported by[21].The storage system works on the principle of evaporativecooling. The process of cooling is based on the principle ofheat transfer from the storage chamber through the wet jutebag which causes the evaporation of the water in the jute bagthere by cooling the storage chamber. The jute bag is wettedby water from the top and bottom water troughs throughgravity and capillary action. Apart from the cooling, thePaper ID: NOV152974evaporative action results in high relative humidity of the airin the storage chamber, making the atmosphere in the storagechamber more conducive to storage of fruits and vegetables,which prevents the drying out of the fruits and vegetablesand therefore extends its shelf life. As long as evaporationtakes place the content of the cabinet will be kept at atemperature lower than that of the environment. The trays arerectangular in shape with an area of 3355cm2 and a volumeof 16775cm3 and thevolume of the top water trough is 26litres while the lower water trough is 44.6 litres.2.3 Theory and basic principle of evaporative coolingsystemEvaporative cooling is a physical occurrence in whichevaporation of a liquid, typically surrounding air, cools anobject or a liquid in contact with it. When considering waterevaporating into air, the wet-bulb temperature, as comparedto the air’s dry-bulb temperature, is a measure of thepotential for evaporative cooling [22]. Evaporation of waterproduces a considerable cooling effect and the faster theevaporation the greater the cooling. When the temperaturesare the same, no net evaporation of water in air occurs, thusthere is no cooling effect. The principle of working of thissystem is ‘when a particular space is conditioned andmaintained at a temperature lower than the ambienttemperature surrounding the space, there should be therelease of some moisture from outside the body’. Thismaintains low temperature and elevated humidity in thespace compared to the surrounding. This evaporative coolchamber fulfills all these requirements and is helpful to smallfarmers in rural areas[4].Evaporative coolers provide cool air by forcing hot dry airover a wetted pad. The water in the pad evaporates,removing heat from the air while adding moisture. Whenwater evaporates, it draws energy from its surroundings,which produced a considerable cooling effect. Coolingoccurs when air, that is not too humid, passes over a wetsurface; the faster the rate of evaporation the greater thecooling. The efficiency of a cooler depends on the humidityof the surrounding air [22]. Very dry air can absorb a lot ofmoisture so greater cooling occurs. In the extreme case of airthat is totally saturated with water, no evaporation can takeplace and no cooling occurs. The evaporative cooled storagestructures work on the principle of adiabatic cooling causedby evaporation of water, made to drip over the bricks orcooler pads. Generally, an evaporative cooler is made of aporous material that is fed with water. Hot dry air is drawnover the material. The water evaporates into the air raising itshumidity and at the same time reducing the temperature ofthe air. Cooling is provided by the evaporative heat exchangewhich takes advantage of the principles of the latent heat ofevaporation where tremendous heat is exchanged when waterevaporates. It makes use of the free latent energy in theatmosphere. The relationship between air and water is shownin the psychometric chart (Fig. 1). Air acts like a sponge towater. The key difference is that as the air increases intemperature it can hold more water.If the ambient conditions of the air are known, then theamount of cooling can be determined using this chart. For anideal evaporative cooler, which means, 100% efficient, theVolume 5 Issue 1, January 2016www.ijsr.netLicensed Under Creative Commons Attribution CC BY1198
International Journal of Science and Research (IJSR)ISSN (Online): 2319-7064Index Copernicus Value (2013): 6.14 Impact Factor (2014): 5.611dry bulb temperature and dew point should be equal to thewet-bulb temperature [23]). The psychometric chart in Figs.1 and 2 explain what happens when the air passed through anevaporative unit.of the storage chamber was taken under no load conditionprior to the introduction of the specimen. The storagechamber was tested for its ability to reduce the temperaturewhile maintaining the increased relative humidity. Theevaporative cooling system was tested under load conditionto preserve tomatoes and hot pepper for 8 days. During theperiod of the experiment, the dry bulb and the wet bulbthermometers were suspended in the storage chamber toascertain the variation of the temperature of the chamberwhile a control sample of the same quantity were spread on atray exposed to the open air.The temperature of the ambient and the evaporative coolingsystem were recorded twice daily (morning and afternoon)using the wet bulb and dry bulb thermometer.Figure 1: Psychometric chart explaining principle ofEvaporating CoolingThe weight loss was measured using a digital weighingbalance. The weight of the samples was measured daily forthe tomatoes and hot pepper until the end of the experiment.The average weight of the samples was determined and themean change in the weight of the respective fruit andvegetable with time during the storage period was calculated.During the period of the study, a periodic attention was takento refill the water in the water troughs as the level of thewater drop below half of the capacity of the water troughsand the total quantity of water used throughout the period ofthe experiment was measured using a calibrated bucketwhich is not within the scope of the study.2.5 Selection of Insulating MaterialW1 Weight of sample before storage, KgW2 Weight of sample after storage, KgAs part of the general requirements, the efficiency of anactive evaporative cooler depends on the rate and amount ofevaporation of water from the filling material. This isdependent upon the air velocity, filling material thicknessand the degree of saturation of the filling material which is afunction of the water flow rate wetting the filling material[26, 27]. Similar filling materials have been used by [24, 28].The ambient and cabinet temperature was measured using adigital thermometer and relative humidity by digitalhumidity–temperature meter. Products weight (preserved andunpreserved) was determined by digital weight balance. Theevaporative cooling system was tested over a period of 8days using 40 kg of tomatoes and 15 kg of hot pepper fruit.The chamber was tested for its suitability to reduce thetemperature while maintaining the increased relativehumidity. During the testing period, the thermometer wassuspended in the chamber through a small hole in the cabinetto ascertain the variation of temperature in the chamber,while a control sample of 40 kg of tomatoes and 15 kg of hotpepper fruit spread on a tray exposed to the open air.2.4 Methodology3. Results and DiscussionThe developed evaporative cooling system was tested usingtwo samples of fruits and vegetables viz; tomatoes and hotpepper. It was tested for a period of eight days for thetomatoes and hot pepper.3.1 Temperature and Relative Humidity VariationFigure 2: Psychometric chart explaining principle ofadiabatic cooling.2.3 Per Cent Loss in Weight (PLW)Percent loss in weight (PLW) was determined by weighingthe vegetables after 8 days interval during storage with theequation used by [24, 25].( PLW ) w1 w2w 1001The experiment was carried out at Agricultural EngineeringWorkshop of Abubakar Tafawa Balewa University BauchiNigeria using 4003 g of fresh Tomatoes and 1056 g of Hotpepper respectively. The temperature (wet bulb and dry bulb)Paper ID: NOV152974The performance of the evaporative cooling system wasevaluated from morning to afternoon at an interval of 1hourfor 8hours daily to the temperature variations for 8 days fortomatoes and hot pepper as shown in Table 1 and 2. Withinthese periods of evaluating the performance of the coolingsystem, theambient temperature kept on increasing with timechanging, the cabinet experienced drop in temperature andVolume 5 Issue 1, January 2016www.ijsr.netLicensed Under Creative Commons Attribution CC BY1199
International Journal of Science and Research (IJSR)ISSN (Online): 2319-7064Index Copernicus Value (2013): 6.14 Impact Factor (2014): 5.611thereafter maintained an appreciable constant lowtemperature value of about 220C with time for the remainingtesting period. However, the average temperature inside thecooling chamber varied from 20 to 23.5 0C while in theambient air temperature varied from 25 to 28 0C for tomatoesand an average of 20.5 to 26.50C inside the Cabinet while inthe ambient air temperature was from 28 to 30.5 0C for hotpepper. Thus, the evaporative cooling system temperatureswereconsistently lower than the ambient air temperaturesduring the hottest time of the day when insulation wasnoticeable and cooling most needed also inside theevaporative cooling chamber. Themean relative humidity ofcabinet during the period of the experimentwas from 51 to93% respectively while the mean relative humidity of theambient environment was observed from 47 to 58% fortomatoes and the mean relative humidity for hot pepper wasfrom 49 to 95% for the cabinet and the mean relativehumidity for ambient was from 47 to 57% as shown in Table2. These results clearly demonstrate that the evaporativecooling system is useful in the study area climate for shortterm preservation of farm products, especially during thehottest time of the day when cooling is most needed asshown in Fig. 1 and 2 below. The results are in agreementwith the findings of [22, 29]. Previous findings showed thatevaporative cooler maintained the temperature between 14.4and 23.50C and relative humidity between 73 and 92%during storage periods [30].Figure 1: Temperature of Cabinet and Ambient conditionagainst time for TomatoesTable 1: Relative humidity and Temperature of Cabinet andAmbient for TomatoesTime8:00 hr9:00 hr10:00 hr11:00hr12:00 hr13:00 hr14:00 hr15:00 hr16:00 hrTemp(Cabinet)23.5 %47%49%50%51%56%Table 2: Relative humidity and Temperature of Cabinet andAmbient for Hot PepperTIME8:00 hr9:00 hr10:00 hr11:00 er ID: 80CRH(Cabinet)57%55%49%48%47%50%52%53%56%Figure 2: Relative humidity of Ambient and Cabinet overTime for Hot Pepper3.2Effect of Temperature and Relative humidity onthe Shelf life of Vegetables.The performance of the evaporative cooling system at astorage period of 8 days for the tomatoes and hot pepper wasachieved as against the 3 days for the ambient storage.During the experiment, rotting was started to observe at 3days of storage for the samples kept in the ambientenvironment while rotting was started to be observed at 8days of storage for the samples kept inside the cabinetcooler, as shown in Figure 3. LalBasediya et al., and Mogajiand Fapetu,[22, 29] also observed that the storage of thesevegetables are within their findings and it was observed thatthe weight loss of tomatoes and hot pepper were minimumwhen the commodities were stored in the evaporative coolingsystem chamber while it was maximum in ambient storage aspresented in Table 3 and 4. The physiological weight lossobtained for the tested samples that is, tomatoes and hotpepper are plotted in Figures 3 and 4 respectively. Theweight of tomatoes stored in open air was maintained foronly 8 days after which there was a sharp decline in weightfrom approximately 40.00 to 15.453kg and hot pepper15.00to10.117 kg for the tested samples respectively after 8 daysof storage, resulting into a loss in weight of about 24.547 and4.883 kgfor the samples respectively. Contrary to thisobservation, tomatoes, and hot pepper kept in the evaporativecooling cabinet had their weight relatively maintained at 39and 15 kg within one weekof storage with only anapproximate 2.95 and 1.138 kg loss in weight for the testedsamples respectively after 8 daysof storage.Volume 5 Issue 1, January 2016www.ijsr.netLicensed Under Creative Commons Attribution CC BY1200
International Journal of Science and Research (IJSR)ISSN (Online): 2319-7064Index Copernicus Value (2013): 6.14 Impact Factor (2014): 5.611Table 3: Weight loss in Tomato (Kg)Days1234567Cabinet40.000 Kg39.783 Kg39.075 Kg38.694 Kg38.145 Kg37.647 Kg37.054 KgAmbient40.000 Kg35.833 Kg31.183 Kg26.946 Kg22.314 Kg19.967 Kg15.453 KgTable 4:Weight loss in Hot pepper (Kg)Days1234567Cabinet15.000 Kg15.653 Kg15.257 Kg14.473 Kg13.704 Kg13.529 Kg13.862 KgAmbient15.000 Kg14.427 Kg12.877 Kg12.134 Kg11.985 Kg11.132 Kg10.117 KgFigure 3: Weight loss of Tomatoes (Kg)The intensity of weight loss during storage depends onmaturity stage [31]. Weight lose of fresh tomatoes isprimarily due to transpiration and respiration. Cold storedfruits have low weight loss due to temperature effects onvapor pressure difference and increased water retention.Rab et al.,[32] reported that the weight loss of tomato fruit issignificantly affected by harvest stages. This finding is inaccordance with the work done by Moneruzzaman et al.,[31]who reported that storage of tomato at low temperature andhigh relative humidity decrease the early deteriorationpercentage.Figure4:Weight loss of Hot Pepper (Kg)Paper ID: NOV152974The higher percentage weight loss in pepper stored atambient conditions compared to those stored in theevaporative cooler appeared to be related to the RH andtemperature surrounding the produce. The evaporative coolerhad more air humidity as well as cooler than the ambientstorage conditions, thereby capable of reducing excessivemoisture loss from the produce as observed by Samira et al.,[33]. The types of surfaces and underlying tissues of fruitmay also have a marked effect on the rate of water loss [34]which could be seen as reasons for the differences observed.4. ConclusionNigeria is one of the humid countries in the world. Producegoes waste due to improper post-harvest operations and lackof enough storage facilities. The evaporative cooling systemhas a very large potential to provide thermal comfort. Today,the evaporative cooling storage system is increasingly beingused for on-farm storage of fruits and vegetables. Theevaporative cooling system not only lowers the airtemperature surrounding the produce, it also increases themoisture content of the air. Thishelps prevent the dryingamount of the produce, therefore, extends the shelf life of theproduce. The evaporative cooling system is well suitedwhere; temperatures are high, humidity is low, water can bespared for this use, and air movement is available. The shelflife of tomatoes and pepper stored in the evaporative coolerwas effectively improved compared with storage underambient condition.The result also showed that maintaininglower temperature and higher relative humidity duringstorage combined with selecting cultivars having long shelflife could maintain fruit quality and reduce loss. Qualityattributes were found to be best which was stored in theevaporative coolerReferences[1] A. I. Ihekoronye and P. O. Ngoddy, Integrated foodscience and technology for the tropics: Macmillan,1985.[2] R. Hanif, Z. Iqbal, M. Iqbal, S. Hanif, and M. Rasheed,"Use of vegetables as nutritional food: role in humanhealth," Journal of Agricultural and Biological Science,vol. 1, pp. 18-20, 2006.[3] E. M. G. Peter, "Vegetables Virtures: edu/howard/mg/advege.htmpp. 1-6, 1997[4] S. M. Dadhich, H. Dadhich, and R. Verma,"Comparative study on storage of fruits and vegetablesin evaporative cool chamber and in ambient,"International Journal of Food Engineering, vol. 4, 2008.[5] A. Dzivama, "Performance evaluation of an activecooling system for the storage of fruits and vegetables,"Ph. D. Thesis, Department of Agricultural Engineering,University of Ibadan, Ibadan Nigeria. 2000. Inproceeding of Nigeria Institution of AgriculturalEngineering, 2013.[6] CFNEU, "Community Food and Nutrition ExtensionUnit”." D-II /183, Kidwai Nagar (West).N.Delhi-110023511 .http:// wed.nic.in/us5.htm, 2003.[7] O. Aremu, "Storage and Preservation of Fruits andVegetable in Nigeria " First National Seminar on FruitsVolume 5 Issue 1, January 2016www.ijsr.netLicensed Under Creative Commons Attribution CC BY1201
International Journal of Science and Research (IJSR)ISSN (Online): 2319-7064Index Copernicus Value (2013): 6.14 Impact Factor (2014): 5.611and Vegetables vol. Caxton Press (West Africa)Limited, pp. 121-126, 1975[8] T. Seyoum and K. Woldetsadik, "Natural ventilationevaporative cooling of mango," J. Agric. Biotechnol.Environ, vol. 2, pp. 1-5, 2000.[9] J. F. Thompson, F. G. Mitchell, and T. R. Rumsay,Commercial cooling of fruits, vegetables, and flowers:UCANR Publications, 2008.[10] CFNEU, "Community Food and Nutrition ExtensionUnit”," D-II /183, Kidwai Nagar(West).N.Delhi-110023511 .http:// wed.nic.in/us5.htm., 2003.[11] A. I. Ihekoronye and P. O. Ngoddy, Integrated foodscience and technology for the tropics: Macmillan,1985.[12] R. Hanif, Z. Iqbal, M. Iqbal, S. Hanif, and M. Rasheed,"Use of vegetables as nutritional food: role in humanhealth," Journal of Agricultural and Biological Science,vol. 1, pp. 18-20, 2006.[13] E. M. G. Peter, "Vegetables Virtures: edu/howard/mg/advege.htmpp.1-6, 1997[14] S. M. Dadhich, H. Dadhich, and R. Verma,"Comparative study on storage of fruits and vegetablesin evaporative cool chamber and in ambient,"International Journal of Food Engineering, vol. 4, 2008.[15] A. Dzivama, "Performance evaluation of an activecooling system for the storage of fruits and vegetables,"Ph. D. Thesis, Department of Agricultural Engineering,University of Ibadan, Ibadan Nigeria. 2000. Inproceeding of Nigeria Institution of AgriculturalEngineering, 2013.[16] CFNEU, "Community Food and Nutrition ExtensionUnit”." D-II /183, Kidwai Nagar (West).N.Delhi-110023511 .http:// wed.nic.in/us5.htm, 2003.[17] O. Aremu, "Storage and Preservation of Fruits andVegetable in Nigeria " First National Seminar on Fruitsand Vegetables vol. Caxton Press (West Africa)Limited, pp. 121-126, 1975[18] T. Seyoum and K. Woldetsadik, "Natural ventilationevaporative cooling of mango," J. Agric. Biotechnol.Environ, vol. 2, pp. 1-5, 2000.[19] J. F. Thompson, F. G. Mitchell, and T. R. Rumsay,Commercial cooling of fruits, vegetables, and flowers:UCANR Publications, 2008.[20] CFNEU, "Community Food and Nutrition ExtensionUnit”," D-II /183, Kidwai Nagar (West).N.Delhi-110023511 .http:// wed.nic.in/us5.htm., 2003.[21] K. Vala, F. Saiyed, and D. Joshi, "Evaporative CooledStorage Structures: An Indian Scenario," 2014.[22] S. Jha and S. Kudos, "Determination of physicalproperties of pads for maximizing cooling in evaporativecooled store," Journal of Agricultural Engineering, vol.43, pp. 92-97, 2006.[23] S. Roy and D. Khurdiya, "Studies on evaporativelycooled zero energy input cool chamber for storage ofhorticultural produce," Indian Food Packer, vol. 40, pp.26-31, 1986.[24] R. Singh and K. Satapathy, "Performance evaluation ofzero energy cool chamber in hilly region," AgriculturalEngineering Today, vol. 30, pp. 47-56, 2006.[25] K. Vala and D. Joshi, "Development of EvaporativeCooling Transportation System for PerishablePaper ID: NOV152974Commodities," Journal of Agricultural Engineering,vol. 47, pp. 27-33, 2010.[26] E. V. Gómez, F. R. Martínez, and A. T. González, "Thephenomenon of evaporative cooling from a humidsurface as an alternative method for air-conditioning,"Journal homepage: www. IJEE. IEEFoundation. org,vol. 1, pp. 69-96, 2010.[27] S. Jha, "Development of a pilot scale evaporative cooledstorage structure for fruits and vegetables for hot and dryregion," JOURNAL OF FOOD SCIENCE ANDTECHNOLOGY-MYSORE, vol. 45, pp. 148-151, 2008.[28] uralMinistry,Govt.ofIndia," 85institutionalareasection–18 Gurgaon122015, 2015.[29] R. Khurmi and J. Gupta, A textbook of Refrigeration andAir Conditioning: S. Chand, 2006.[30] R. Kenghe, A. Magar, and K. Kenghe, "Design,Development and Testing of Small Scale MechanicalFruit Washer."[31] A. lal Basediya, D. Samuel, and V. Beera, "Evaporativecooling system for storage of fruits and vegetables-areview," Journal of food science and technology, vol.50, pp. 429-442, 2013.[32] J. R. Camargo, "Evaporative cooling: water for thermalcomfort," Ambiente & Água-An InterdisciplinaryJournal of Applied Science, vol. 3, pp. 51-61, 2008.[33] W. A. Olosunde, J. Igbeka, and T. O. Olurin,"Performance evaluation of absorbent materials inevaporative cooling system for the storage of fruits andvegetables," International Journal of Food Engineering,vol. 5, 2009.[34] R. Wijeratnam, V. Pierisl, I. Hewajulige, and N.Amarasinghe, "Development of low cost storage systemfor extending storage life of lime, tomato, mango andpapaya," CARP, CompetitiveContract Research GrantsProgramme: Proceedings, Presentations of CompletedResearch Projects, 2005, p. 14, 2005.[35] F. Wiersma, "Evaporative Cooling in Ventilation ofAgri
cooler pads. Generally, an evaporative cooler is made of a porous material that is fed with water. Hot dry air is drawn over the material. The water evaporates into the air raising its humidity and at the same time reducing the temperature of the air. Cooling is p
air-coolers using HMX's patented Indirect Direct Evaporative Cooling technology (also known as two-stage evaporative air cooling). This cooling solution consumes considerably less power than air-conditioners and provides better comfort than ducted evaporative coolers, bringing evaporative air cooling technology a step closer to air-conditioning.
Developers have moved to green cooling technique to save energy in unique way. Besides air cooling, evaporative water cooling, oil immersion cooling has gained rapid acceptance in data center cooling area. [1]. Evaporative cooling has been taking place over air-cooling system because of the cooling
The sub wet-bulb evaporative chiller (SWEC) uses an evaporative cooling process to chill water for use in building cooling systems. The SWEC utilizes a two-stage evaporative cooling system to chill water below the web-bulb temperature of the outdoor air. The theoretical limit for the supply water temperature is the dew point of the outdoor air.
Fig. 3: Indirect Evaporative Cooling 3) Combined Evaporative Cooling This type of evaporative coolers combines both direct and indirect evaporative cooling. This is accomplished by passing air inside a heat exchanger that is cooled by evaporation on the outside.In the second stage the pre cooled air is passes
air-coolers using HMX's patented Indirect Direct Evaporative Cooling technology (also known as two-stage evaporative air cooling). This cooling solution consumes considerably less power than air-conditioners and provides better comfort than ducted evaporative coolers, bringing evaporative air cooling technology a step closer to air-conditioning.
Best Practices for Wetted‐Media Evaporative Cooling August 13, 2014 Best Practices for Fogging Evaporative Cooling October 8, 2014 Best Practices for Chiller Systems December 12, 2014 . Conductivity 750 mhos Suspended Solids 5 PPM pH 6.0 to 8.5 * Need to be evaluated as a system, not in isolation. Water Quality & Management .
Scenario 3: Indirect evaporative cooling via water-to-air HX with cooling tower. In this configuration, a water-to-air HX is located upstream of the main cooling coil on the supply deck. The water-to-air HX is similar to a regular finned tube water cooling coil except that the "chilled" water comes from a cooling tower rather than a chiller. The
Two evaporative cooling systems are commonly used in greenhouses: the pad-and-fan and the fog system. Pad-and-fan systems (Figure 1) are part of a greenhouse's mechanical ventilation system. Note that swamp coolers can be considered stand-alone evaporative cooling systems, but otherwise operate
