Wind energy is becoming one of the key renewable sources of energy in the United States and the world due to its environmental and economic... Show moreWind energy is becoming one of the key renewable sources of energy in the United States and the world due to its environmental and economic advantages and absence of water requirements. The performance of a wind turbine is largely affected by surrounding environments and the total power output of a wind farm is closely related to meteorological phenomena such as rain and icing. Investigating the effects of these phenomena is necessary to improve the design and performance of the wind turbines. In this research, we focused on the study of wind turbine performance in rainy conditions as the stepping stone to the future study of icing. We applied Computational Fluid Dynamics (CFD) technology to investigate the impact of rain on wind turbines. A novel model coupling the Lagrangian method with the Eulerian method was developed. The rain droplet was tracked in the Lagrangian frame due to its discrete nature, and the film formed on the wind turbine was simulated with the Eulerian Volume of Fluid Model (VOF). The performance loss and impact on the flow field were also studied. Numerical studies have been conducted on 2-Dimensional S809 airfoils and 3- Dimensional Horizontal Axial Wind Turbines (HAWT). The performance loss under heavy rain conditions was observed and the flow field was analyzed. The impact of air moisture content on wind turbine performance was also studied using our 3-D model. Due to the lack of experimental data on wind turbine performance under heavy rain conditions, our coupled two phase flow model was applied to a NACA 64-210 airfoil to compare with the experimental data in rainy conditions. Simulation results using our model showed good agreement with the experimental data. M.S. in Chemical and Biological Engineering, May 2012 Show less
