Effect of Air-Ducted Blade Design on Horizontal Axis Wind Turbine Performance

Abstract

Wind turbines without pitch control are more preferable from economical point of view but aerodynamic stall affects them more and after a critical wind speed local boundary layer separation occurs. Consequently, their power production is relatively low. In this study, air ducts added on the blade and using the airflow from them the kinetic energy of the low-momentum fluid behind the surface was increased and delay of separation of the boundary layer from the surface was examined The Response Surface Optimization method was utilized in order to get the best possible design under the constraints and targets arranged for the parameters termed the diameter, slope, number and angle of attack of the air ducts. By using computational fluid dynamics analysis, optimum parameter values were obtained and air-ducted and air-duct free blade designs were compared. An improvement in power coefficient between 3.4–4.4% depending on wind speed was achieved with the new design. Due to increase in viscous forces, more power from the rotor obtained by opening air ducts up to a critical number. However, the results showed that after the critical number of air duct addition of more duct on the blade reduced the power coefficient.

Design, Manufacturing and Testing of Inversed Taper NACA 4412 Airfoil with Blade Made of Hybrid Empty Fruit Bunch Bio-composites

“…Its selection requirements for blade profile design were chosen from large CL/CD values based on the angle of attack (α) [22]. The force of the component perpendicular to the direction of flow is called the lift force (FL), while the force of the component in the direction of flow is called the drag force (FD) [28]. Therefore, the selected airfoil was NACA 4412 [29].…”

Parametric Study on Ducted Micro Wind Energy Harvester

“…In addition, studies on improving the performance of diffuser-augmented wind turbines and Energies 2022, 15, 727 2 of 12 CFD analysis have been conducted. The research to derive the optimal shape through CFD analysis of rotor blade contours in wind turbines with ducts was presented [17][18][19][20]. It was confirmed that the performance of the diffuser type duct varies depending on the yaw angle of the inlet [21][22][23][24].…”

Optimal Design and Aerodynamic Performance Prediction of a Horizontal Axis Small-Scale Wind Turbine

“…Typically, a wind turbine blade needs a far-field domain of 10-20 times the rotor diameter [45]. However, considering the calculation cost, area immediately adjacent to the wake of the wind turbine [46], 3D helical vortex structure [47], empirical value [48][49][50], and comparison of the calculation zones of different sizes, the rotation and stationary domains are finally modeled into a cylinder shape with diameters of 1.1 and 4D and heights of 0.22 and 7.22D, respectively. e distance from the inlet to the rotation domain is 2D, and the distance from the outlet to the rotation domain is 5D.…”