INVESTIGATION OF THE AERODYNAMIC FORCES OF A TRIANGULAR WIND TURBINE BLADE FOR THE LOW WIND SPEEDS

Abstract

This article investigates the aerodynamic characteristics and finds the critical angle of attack of a triangular sail blade of a wind turbine for low wind speeds. For this purpose, a triangular sail blade of various parameters has been developed. The prototype is made of metal frame rods, the material of the triangular sail blade consists of a light and durable material (silk), one end of which is fixed to the top of the frame with a strong thread and support rods and bearing with an inner diameter of 8 mm. A sail blade differs from other blades in that the sails are made with the ability to change the angle of attack using a movable thread. To determine the critical angle of attack, the aerodynamic forces of the sail blade were investigated at different angles of attack 00 ; 150 ; 300 ; 450 , 600 ; 750 ; 900 . From the data analysis, it was found that the critical angle of attack is 150 , at which the value of the lift is maximum. Furthermore, at the critical angle of attack, the dependences of the lift and drag force on the air flow velocity were established, the value of which varied from 4 to 12 m/s.