Effects of rain on vertical axis wind turbine performance

The ambient atmospheric environment significantly affects the performance of wind turbines operating in different meteorological conditions. As rain is a common meteorological condition, the understanding of rain effects on the performance of wind turbines can be helpful in selecting a proper site for a new wind farm. This paper comprehensively investigates the effects of rain on a NACA 0015 airfoil, which is commonly used in VAWTs (vertical axis wind turbines). A two-way coupled Eulerian-Lagrangian multiphase approach is proposed to study the rotating and oscillating performances of the NACA 0015 airfoil in rainy conditions. It is found that the VAWT performance can seriously be deteriorated in different rain conditions. Following is an exploration of the potential physics behind the interaction between the raindrop and the airfoil. Finally, the dimensional influence on evaluating rain effects on the wind turbine performance is investigated.