Improvement aerodynamic performance of a wind turbine using injecting air jet and Taguchi optimization.

Improvement of flow separation around the horizontal axis of the sixth phase wind turbine was investigated by installing air jets. Using Taguchi method and using control parameters, the optimal combinations, and the level of importance of the parameters in increasing torque production were obtained by analyzing the signal-to-noise ratio and variance, and the torques were optimized. It was found that the importance of the parameters on increasing the torque includes the ratio of speed, chord position and longitudinal position, respectively .So a turbine consisting of twelve jets with a width of 0.04 local chord was simulated and numerically solved in the chord positions of 0.1-0.3-0.5 and 0.7 with Fluent software 18.2 and kω-SST turbulence model. Longitudinal places consist of three parts: outer, middle and inner. The velocity ratios for the output jet are 0.2, 1.2, 2.2, 2.8 and 3.2. The results showed that torque changes are dependent on changes in dimensionless parameters such as jet velocity ratio, chord position and longitudinal position. The aerodynamic effects of double, triple and quadruple jets were compared with single jets and the increase in torque was observed due to the improvement of the flow pattern due to the reconnection of the current separated from the blade surface, especially at the blade tip. Exterior jets were more effective in increasing torque, and at best, the torque produced by the T1 jet increased by 132%, or more than double, and was reported as the peak of torque increase.