This cooling technology is promising to develop in the near future due to its very low energy consumption and high efficiency in its range of applications. Indirect evaporative cooling does not add moisture to the primary air stream making it ideal for highly specialist manufacturing and production facilities. A national renewable energy laboratory assessment of indirect evaporative coolers found that the technology reduced energy use while maintaining thermal comfort, but it can be difficult to find favorable economic payback. When warm, dry unsaturated air is pulled through a watersoaked pad, water is evaporated and is absorbed as water vapor into the air. Evaporative cooling capacity ranges from 6,000 cfm to over 100,000 cfm. Evaporative cooling solutions, fanair, celair, indirect. Then the air continues through our direct evaporative cooler where the air is mixed with water to add a bit of moister to the air. This adiabatic cooling process is also used to create the chilled water that feeds our indirect evaporative cooling coil. With oasis, the energy required to remove heat is significantly reduced. For steam humidifiers, this energy typically comes from the electricity or gas being used to boil the water. Desiccant evaporative cooling and indirect evaporative cooling were used to increase the energy performance and reduce energy consumption.
The basic structure of the cooling chamber can be built from bricks and river sand, with a cover made from cane or other plant material and sacks or cloth. Munters systems use coolingheat rejection strategies that achieve a. Indirect evaporative cooling 80% energy usage reduction. Circulating 100% fresh air throughout your home, an aolan evaporative air conditioner will constantly refresh and change the. Evaporative cooling is the most energy efficient and cost effective form of cooling that exists. The three multistaged indirect evaporative cooling units were monitored from june 1. The main difference with an indirect system is that a heat exchanger is used to cool the air supplied to the living spa. With indirect cooling, the water is reused repeatedly by being recycled in a closed loop system. As air is drawn through this, cascading water provides evaporative cooling, similar to an open cooling system, except that the cooled water is never allowed to make direct contact with the air. Celair units are extremely heavy duty and are an excellent choice for all static pressure applications. Mar 01, 2016 28 indirect direct evaporative cooling idec with indirect direct evaporative cooling, the primary air stream is cooled first with indirect evaporative cooling and then cooled further with direct evaporative cooling.
Evaporative cooling an overview sciencedirect topics. There are two types before we go there, you must understand humidity the humidity content decides how comfortable a person feels for ex. The use of an indirect evaporative cooling system in conjunction with a mechanical ac system o. In a direct evaporative cooler, a blower forces air through a. Owing to the continuous progress in technology innovation, particularly the mcycle development and associated heat and mass transfer and material optimisation, the iec systems have obtained significantly enhanced cooling performance over those the decade ago, with the wetbulb effectiveness of greater than 90% and energy efficiency ratio eer up to 80. Direct evaporative cooling and ventilation technologies. The air supplied into a conditioned room by the main supply fan is called the primary air stream. The cooling media does not come into direct contact with the product, so no dust or emissions are created.
Equipment cost is lower than a refrigeration system, installation is simple and inexpensive, and operating costs are a fraction of refrigeration systems. Applications include 100% outside air, and multistage systems that combine indirect evaporative cooling with. Evaporative cooling code compliance brief building. The main difference with an indirect system is that a heat exchanger is used to cool the air supplied to the living space. Direct air evaporative cooling for buildings and areas that do not have a central air conditioning system, direct air evaporative cooling can be a very economical and achievable way to reduce the temperature. Indirect evaporative cooling, regenerative cooling, dew point cooling, maisotsenko cycle, energy efficiency 1. Primary air is cooled sensibly with a heat exchanger, while the secondary air carries away the heat energy from the primary air as generated vapor. Qatar national research fund a member of qatar foundation. Indirect evaporative cooling aolan evaporative air cooler. Evaporative cooling is when your body feels cool by passing air that evaporates the water on your skin.
In fact, second to information and communication technology ict equipment, the mechanical cooling system is the highest energy consumer in a data center. This conditioned air is supplied directly to the room with a high percentage of the room air being exhausted, rather than recirculated, to maintain a low humidity level in the room. It is the same cooling principle that our body uses when moisture sweat evaporates and cools the skin. Indirect evaporative cooling direct and indirect evaporative cooling are extremely energy efficient, negating the need for compressors in the cooling cycle. Munters oasis standard indirect airside economizer iase with indirect evaporative cooling iec takes advantage of evaporation to reject heat without ever adding any moisture to the data center. Another indirect cooling tower system involves a separate heat exchanger and an open cooling tower. In general, there are three types of evaporative cooling systems. Aztec indirect and indirectdirect evaporative cooling. Operating cost is an important factor when utility budgets are a major consideration.
Evaporative cooling systems evaporative air conditioning is a healthy way to keep your family cool and comfortable in our long, hot, demanding summers at a fraction of the running cost of reverse cycle air conditioning. Humidity is added to the incoming fresh air stream, reducing its temperature whilst increasing its humidity. Evaporative cooling, on the other hand, relies instead on the inherent quality of water to absorb heat when it evaporates changes from a liquid to a gas. Indirect evaporative cooling works on the same principle as direct evaporative cooling lowering air temperature by causing water to evaporate. Renewable and sustainabl e energy rev iews 16, 6823 6850.
Applied air offers direct evaporative cooling equipment with air deliveries from 3,000 cfm to 64,000 cfm and indirect or indirectdirect evaporative cooling units with air deliveries from 1,500 cfm to 37,500 cfm. To evaporate 1kg of water into an atmosphere, 680w of energy is required. Aolan evaporative air cooler,portable air cooler,indirect evaporative air cooler and liquid desiccant air conditioning,cooling pad manufacturer has been providing homes,factory,farm with the air,efficient water evaporative cooling system for over 20years. Adjustable sump water bleedoff valve assembly in cooling tower and direct evaporative section. Custom manufacturer of indirect evaporative coolers. A direct evaporative cooling system is the simplest and most popular evaporative cooling system available. Evaporative cooling differs from typical air conditioning systems, which use vaporcompression or absorption refrigeration cycles. 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. For example, while some people mind the additional ventilation required, others enjoy opening their home up to natural light and fresh air. Air drybulb temperature, rh, water flow rate, air velocity.
The evaporative cooling cycle occurs in the heat exchanger. Direct evaporative cooling adds moisture to the air stream close to saturation. However, there are other compelling reasons that make evaporative cooling a smart choice. Performance evaluation for indirect evaporative cooling etsce7 southern california edison page iii emerging products june 2015 abbreviations and acronyms 6 cooling capacity, enthalpy flow rate e. Evaporative air conditioning is a healthy way to keep your family cool and comfortable in our long, hot, demanding summers at a fraction of the running cost of reverse cycle air conditioning. Aolan evaporative air cooler,portable air cooler, indirect evaporative air cooler and liquid desiccant air conditioning, cooling pad manufacturer has been providing homes,factory,farm with the air,efficient water evaporative cooling system for over 20years. Evaporative cooling systems can significantly lower the outside air temperature, even in humid climates, and improves the ability of the ventilation air to reduce the heat in the area. Spray humidifiers deliver moisture to an atmosphere using either high pressure or compressed air to ensure evaporation. What is the difference between direct and indirect. Thus no water loss is associated with the cooling process. In addition, water ponds favouring the evaporative cooling were identified as one of the potential mitigations for uhi 5, 17, 30. Then the air is pushed into the building by the fan or blower.
Applications include 100% outside air, and multistage systems that combine indirect evaporative cooling with dx, chilled water or direct evaporative components. When evaporative processes are used to cool an element of the building, which then acts as a heat sink, this is known as indirect evaporative cooling. Refer to figure 5 for a schematic view of an indirect evaporative cooling section located upstream of a direct eac. In a direct evaporative cooler, a blower forces air through a permeable and watersoaked pad.
In hot humid climates with a high relative humidity, the air becomes fully saturated reducing the effect of evaporative cooling. Evaporative cooling is a well recognized method of cooling 40% of new mexico offices, shops, warehouses, laundries, kitchens and institutional facilities. Evaporativecooling air conditioning systems use the cooling effect of the evaporation of liquid water to cool an air stream directly or indirectly. The whole idea is simply to prevent contamination of the water in the system and it is used in food processing.
The second stage is handled by conventional air conditioning. Biggest problem facing the indirect evaporative cooling iec technology lies in its high level of dependency to ambient air condition. Evaporative cooling systems perform more efficiently with reasonable cooling capacities particularly in. 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.
Differentiating between direct and indirect evaporative coolers there are two broad types of evaporative coolers available on the market, direct and indirect, both commonly known as twostage. Evaporative cooling is one of natures fundamental methods of cooling. 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. A range of filtration products up to f7 eu7 grade are available. Evaporative cooling units are also environmentally friendly as they cool efficiently without. Evaporative cooling is based on the thermodynamics of evaporation of water, i. Applied air offers direct evaporative cooling equipment with air deliveries from 3,000 cfm to 64,000 cfm and indirect or indirect direct evaporative cooling. The dry bulb temperature is reduced, while the wet bulb temperature stays the same. Indirect evaporative cooler westaire engineering inc. Evaporative cooling design guidelines manual the benefits of using evaporative cooling in new mexico are usually perceived in terms of economy of operation.
You get 2 stages of evaporative cooling while offsetting substantial energy costs. Improved iaq, resulting from higher ventilation rates when cooling is required 3. A heat section can be added to most models to provide a. These high capacity units come in 24 cataloged formations and range in size from 6,000 cfm to over 100,000 cfm. In addition, we can design the indirect evaporative heat exchanger to be used for heat recovery when ambient conditions requiring heating. The paper presents actual knowledge concerning the indirect evaporative cooling iec. You can duplicate the principle behind direct evaporative cooling by wrapping a wet handkerchief around your neck on a hot day and standing in front of a fan. Course contents evaporative coolers, often called swamp coolers, are cooling systems that use only water and a blower to circulate air. The performance data for the ing units for the month of june indicated that the units cool were not operating correctly and that the units were not providing sufficient cooling. There are also hybrid specialist solutions that you may find interesting to explore in more detail. Evaporative cooling design guidelines ced engineering. Impacts of indirect evaporative cooling to data centers in. Ecocooling products are based on direct fresh air cooling. This eliminates the need for pollution control equipment and makes tight emission limits easier to meet.
Dec from a to e evaporates moisture and cools the air without. Despite the drawbacks listed above, evaporative cooling can still be a great solution for many homesdepending on your specific preferences. First air is drawn through westaires custom heat exchanger to provide the first stage of cooling of the outside air. Impacts of indirect evaporative cooling to data centers in gcc countries. Introduction the evaporative cooling ec technology is based on heat and mass transfer between air and cooling water. It is strongly recommended that all it cooling systems using direct evaporative cooling be designed with a minimum of g4eu4 grade filtration at both the supply and. It could be a factoryassembled packaged unit or a fieldbuilt system.
Evaporative cooling practical action 3 any part of the country using locally available materials. Equinix use oasis indirect evaporative cooling data economy. An indirect evaporative cooling system passively cools the supply air by passing over a medium that has been directly evaporatively cooled on an adjacent but isolated side. Try a new, improved swamp cooler green homes mother. It takes heat energy to change the water or any liquid from a liquid into a vapor. Direct evaporative cooling provides air washing that removes some pollen and other particulate benefits of applying direct evaporative cooling. Direct and indirect evaporative cooling strategies. The munters oasis indirect evaporative cooling systems take advantage of evaporation to reject heat without adding moisture to the data centre. These hvacs come factory assembled, prewired, and are self contained, packaged units. With direct evaporative cooling, outside air is blown through a watersaturated medium usually cellulose and cooled by evaporation. Experimental and numerical study of a heat pipe based. Pdf indirect evaporative cooling with an outdoor pond. The amount of cooling provided is driven by the dryness i.
Indirect evaporative cooling 2015 nova award nomination 25 air enthalpy h energy btu lb dry air is shown by left sloped line values for left to right down lines, and its value is determined by its wb. Evaporative cooling market growth, trends and forecast. Cooling is provided whilst keeping the evaporative process outside, which avoids elevating the indoor humidity level. By incorporating in our direct evaporative cooler with our indirect evaporative cooler you get the best of both worlds. Evaporative cooling uses the fact that water will absorb a relatively large amount of heat in. The code officialbuilding official must examine, or cause to be examined, construction documents for code compliance. 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. Cooling is provided whilst keeping the evaporative process outside. The technology can be applied in numerous applications, including data centers, factories, livestock and greenhouses.
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