Evaporative Cooler | Limitations and Applications

Evaporative Coolers | Limitations and Applications

Limitations

The evaporative coolers have some limitations and disadvantages:

1) Evaporative coolers are not effective in the humid regions.

2) High humidity conditions decreases the cooling capability of the evaporative cooler.

3) Cooled air may bring dust and pollen into the space causing discomfort for allergy sufferers. Growth of microorganisms such as molds on the cooler pads may cause allergy problems in sensitive individuals.

4) Coolers are aesthetically unattractive and if not maintained the overflow of concentrated salts can damage building envelope.

5) The vents that allow air to exit the building may pose a security risk.

6) Evaporative coolers cannot be used anytime there is freezing temperatures outside. They must be shut down before it freezes in the fall, and started up after the last freeze in the spring.

7) Since it utilizes water as the cooling medium (which is a corrosive), they can be finicky when pipes get clogged or dirty. This can create a safety issues, noise concerns or an indoor air quality problems in a heavy dust storm.

8) Evaporative coolers can be hooked up to existing forced air duct systems. Because the air delivered by an evaporative system will be warmer than the air supplied by an air conditioner. However, evaporative cooler need to produce more air flow.

9) The cooling effect of an evaporative cooler is dependent on dry air. When the ambient humidity level increases, the cooling effect of an evaporative cooler decreases.

Applications

Evaporative heat exchanger is widely used for cooling of heat process fluids in power generation plants, chemical plants, steel plants, petroleum refineries, nuclear power plants, air conditioning & refrigeration industries etc.

· Persian architectural devices used for natural ventilation of buildings by enhancing the air draught through the structure.

· People and efficiency

Sports events and exhibition halls, chillers and gas turbines all use direct evaporative cooling to achieve the goals of cooling athletes and delegates, increasing chiller efficiency by cooling the surrounding air and increasing air density to improve turbine efficiency respectively.

· Food and Drink

Food and drink manufacturing routinely creates a hot environment which can be detrimental to comfort, product quality and equipment performance and reliability. Evaporative Water Cooling can help address this in a low cost and hygienic solution:
provide cooling at a fraction of the cost of a traditional refrigeration unit with
Insect screens on all coolers.

· Factories

Factories where heat is generated by machinery and are open plan areas with large air volumes, employ direct evaporative cooling. Printers, textile factories, automotive plants etc are good examples of where high pressure water or compressed air and water systems introduce moisture at high level within the factory. This is generally where the warmest air is, so aiding evaporation of the moisture creating the cooling effect required. The cooler, heavier air drops down causing a flow of cool air towards the required zone to be controlled.

· Evaporative (wet) cooling towers

Cooling towers are structures for cooling water or other heat transfer media to near-ambient wet-bulb temperature. Wet cooling towers operate on the evaporative cooling principle, but are optimized to cool the water rather than the air. Cooling towers can often be found on large buildings or on industrial sites.