Experimental and numerical investigation into effect of different blade configurations on performance of small-scale wind turbines

Abstract

Experimental investigations and numerical analysis using Ansys CFD software of the effect of different blade configurations on the performance of small-scale wind turbines are presented in this paper. A complete test rig of small-scale wind turbine is built, and three-dimensional computational model of the rotor system is created and simulated using Realizable K−εturbulent model to evaluate the performance of four types of blade configurations (Twisted blades with NACA0012, Straight (untwisted) blades with NACA0012, Twisted blades with NACA4418, Straight (untwisted) blades with NACA4418). The experimental and numerical analysis has been carried out at various wind speeds in the range of 2 m/s to 8 m/s to study the variation of power coefficient for different configurations of blades with wind speed and choose the most effective design of blades. The results show that the numerical solution over predicts the power produced compared to the experimental test field for all tested blades configurations. The maximum deviation was around 15 percent between the numerical and experimental results and decreased with increasing wind speed. Untwisted blades with NACA0012 are the most effective design of blades suitable for small scale wind turbine based on numerical and experimental results, giving an average of actual power coefficient (Cp = 0.41). Compared to all tested configuration, this design is simple in manufacturing with minimum cost.

Keywords

• Renewable energy
• CFD
• HAWT
• Twisted blades
• Untwisted blades
• NACA0012 and NACA4418