Case Study: Evapco, Cooling Nozzle, Uniform Flow Distribution
Evapco High Performance Cooling Nozzle
Key features
- Large spray area -- 4-8 sq ft from 12" away
- 25-60 gpm
- 1-6 psi operating pressure
- 1" minimum opening
- Up to 3.5% increased efficiency
Increasing the efficiency of cooling tower nozzle through better spray distribution. By producing a better cooling nozzle, we were able to greatly improve uniform flow distribution.
Since its founding in 1976, EVAPCO Inc., headquartered in Taneytown, MD, has become an industry leader in the engineering and manufacture of quality heat transfer products for commercial HVAC, industrial processes, power, and industrial refrigeration. They are a global provider of both factory-installed and field-erected cooling towers.
Challenge
Cooling towers remove waste heat from water by spraying it over a media surface. A counterflow of cool air is induced through channels in the media. Within the channels, air comes in contact with water film on the media, resulting in cooling evaporation.
The water film on the media should be as uniform as possible-- heavy loading of water in some parts of the media and light loading in others will lead to highly inefficient cooling.
Evapco approached Bowles in 2004, looking to improve uniform flow distribution in their cooling nozzles for their factory-installed cooling towers. In addition, the current nozzles, which had been in the market for about 25 years, would frequently clog or foul. Evapco wanted to increase the minimum dimension from 3/8” to 1” -- making their nozzles virtually clog free!
This is an especially challenging task because it involved a large spray area, high flow rates, and a relatively low operating pressure.
Solution
Bowles developed the Evapjet high performance fluidic nozzle for this application. During development, we emphasized uniform spray distribution and large minimum dimensions. The development process included full scale cooling tower thermal efficiency testing. The resulting nozzles have 1” openings, over 3% improvement in thermal efficiency and replaces approximately 2 to 3 of the existing nozzles with each Evapjet nozzle. The Evapjet nozzle flows about 40gpm at 3psi. This technology was eventually extended for Evapco’s field-erected cooling towers as well.
Links
More information
Contact Dr. Sri Sridhara at ssridhara@bowlesfluidics.com or (410) 381-0400 x 273
