CFD-based Performance Analysis on Design Factors of Vertical Axis Wind Turbines at Low Wind Speeds

Abstract

This paper presents effects of design factors on mechanical performances of Vertical Axis Wind Turbines (VAWTs), which are suitable to low wind speeds conditions in Thailand. Potential VAWTs models are numerically analyzed within virtual wind tunnels at low wind speeds by utilizing X-FlowTM Computational Fluid Dynamics (CFD) software. Design factors include types/patterns, numbers of blades, types of materials, height-to-radius ratios and design modifications in this study. The performance curves of each VAWTs are represented by plots of power coefficients against tip speed ratios. It is found that the types/patterns, numbers of blades, and height-to-radius ratios have significant effects on mechanical performances whereas types of materials result in shifts of operating speeds of VAWTs. The proposed methodology can be used in designing VAWTs to improve mechanical performance before physical fabrication.