Session: 08-15-01: Wind and Water Power

Paper Number: 94744

94744 - Investigation of the Leading-Edge Erosion of Wind Turbine Blades Using Multivariant Analysis Method 

With the increase in greenhouse gas production from fossil fuel sources, investing in alternative sources with minimal carbon footprint has become necessary to compact global warming. Wind energy has seen steady growth for the last 40 years. With the vast development in the wind energy industry, new climates that might be considered harsh on wind turbines are being investigated. One such harsh climate is the desert and arid climates with the high frequency of sandstorm occurrences. During a sandstorm, sand particles of different sizes and shapes collide with wind turbine blades at different angles of attack and different impact velocities, causing an enormous amount of damage, especially at the leading edge area of the wind turbine blade. The leading edge erosion causes a drastic decrease in the turbine's overall efficiency and consequently the amount of energy produced. The decline in efficiency occurs due to altering the original shape of the wind turbine blade’s airfoil, which changes optimum aerodynamic performance by increasing the aerodynamic drag and decreasing the aerodynamic lift. Also, the erosion damage causes a mass imbalance in the turbine and can lead to the destruction of the blades if left unrepaired. In this paper, a statistical study is conducted to investigate the effects of multiple variables such as air pressure (consequently the particle impact velocity), which was varied from 100 kPa to 125 kPa to 200 kPa. The second variable was erosion duration, which was varied from 180 seconds to 360 seconds. The last variable angle of attack was varied from -5˚ to 10˚ in 5˚ increments. These three variables were used to closely imitate the conditions during sandstorms. The outcome of the erosion process is measured in terms of mass loss and depth of erosion scars. Using the three variables and the erosion process outcomes, the erosion pattern of the leading edge of wind turbine blades has been characterized. Afterward, the resulting damage of the erosion process was analyzed using the Analysis of Variables (ANOVA) method. It has been found that the angle of attack has a significant effect on the erosion behavior, with the most severe damage occurring at a 0˚ angle of attack for both the amount of mass loss and the depth of erosion scars, while the lowest amount of damage occurring at a 10˚ angle of attack. Similarly, increasing impact velocity and erosion duration caused the most severe damage, and these variables were used to characterize the behavior of the leading edge erosion of wind turbine blades.  

Presenting Author: Abdullah F. Alajmi Kuwait University

Presenting Author Biography: I'm an Assistant Professor at Kuwait University interested in developing methods and solutions to implement renewable energy technologies in harsh environments. I recently graduated from the University of Washington, where my Ph.D. work focused on investigating the leading edge erosion of wind turbine blades due to sand particles impingement and the effects of different protective coatings (especially graphene) in minimizing the damage caused by particles impact.

Authors:

Abdullah F. Alajmi Kuwait University
M. Ramulu University of Washington