Influence of slat and flaps arrangement on the performance of modified Darrieus wind turbine

Due to exhausting fossil fuels and rising costs of the derivatives of fossil fuels, increasing instabilities of the energy market and global warming, the interest in the renewable sources of energy are increasing especially the wind energy. At low wind speeds and for off-grid power generation on a small scale, VAWT possesses the greatest potential than other types of wind energy conversion systems. This works aims to study the influence of auxiliary straight blades, slat and flaps arrangement configured to the micro-Darrieus style wind turbine model on its performance which is developed specifically for energy conversion on a small scale at low wind velocities. The micro-wind turbine model in the present work comprises of three sets of five airfoils. Each set comprises of an auxiliary airfoil, the main airfoil, a slat and two flaps configured at the leading edge and the trailing edge of the main airfoil with multiple chord lengths. The proposed model, the Darrieus model having standard blades configuration and auxiliary straight blades configuration are designed in Solidworks. The wind tunnel experimentations were carried out on the additive manufactured (AM) models 3D printed by SLS technique to compare their performance. The outcomes of the study were expressed in terms of dimensionless torque, moment and power coefficients for performance evaluation analysis. The proposed blades configuration showed a best self-starting ability at low wind velocity and high value of torque coefficient than the micro-Darrieus style wind turbine with standard configuration and auxiliary blades configuration. From this study, it was also found that the wind turbine with the configuration of the proposed blades showed a reduction in cut-in-speed.