Wind Barriers to Mitigate Wind Effects on Air-Cooled Condensers
As more power plants in California and elsewhere are increasingly choosing air-cooled equipment to conserve water, it is imperative that a more rigorous and reliable approach to mitigating wind effects be available.
Menlo Park, CA
This study evaluated the effects of wind protection screens and barriers used to minimize damage from ambient wind on air-cooled condensers in thermal power plants, based on field testing, physical modeling, and computational modeling. Field test measurements demonstrated a significant reduction in wind-induced stress on the fan blades when the windscreens were deployed compared to that experienced when screens were retracted. Over most of the ambient wind conditions, the position of the wind screens showed little effect on the air-cooled condenser thermal performance.
The use of air-cooled condensers (dry cooling) can facilitate energy deployment by significantly reducing power plant water demand, but increases costs and reduces power plant efficiency. Wind is one factor that can significantly reduce air-cooled condenser performance and can lead to reductions in generation or actual plant shutdown. There is a need to improve our understanding of how air flows around and through an air-cooled condenser and how condenser performance can be improved through the use of wind barriers.
To develop guidance on the design and siting of wind barriers on power plant air-cooled condensers, this project included data collection on air velocity and temperature under a variety of wind conditions at an operating power plant with an air-cooled condenser. The collected data was used to validate mathematical (computational fluid dynamics) and physical (wind tunnel) modeling. These modeling efforts allowed the simulation of a range of conditions to develop correlations of wind barrier effectiveness with barrier characteristics and wind conditions.[br/][br/][br/][br/][br/]
Results from the physical and analytical modeling suggest that modeling can provide valuable predictive information in selecting the most suitable design and positioning of wind barriers for air-cooled condensers..
High cross winds over 20 mph on a hot day can reduce steam turbine output by 10 percent or more. Even if these conditions occur for only five percent of the year, for a 500 MW power plant, this represents an annual loss of over 6,000 MWh. Careful design and placement of wind barriers, however, can reduce this loss by over 50 percent
University of California - Davis