Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
Invelox is a structure that increases the wind velocity by collecting air from the higher level of ground. Previous studies showed that Invelox has the potential to capture air and increases the speed of wind, which means more power output. Although it was claimed that Invelox can capture air from all directions, its performance greatly depends on the angle of wind. In this study, the performance of Invelox is analyzed and improved for different wind directions by changing the number of blades. The results showed, however, the aerodynamic performance of all proposed Inveloxes has decreased due to increasing the wind angle, the five-blade Invelox outperforms the original model in output power by about 7%-20% in various wind directions. Furthermore, in order to reduce air escaping from the opposite side of Invelox, the length of the upper funnel has been increased. Results showed about 12% improving performance when the length of the upper funnel is equal to its diameter. The three dimensional models were analyzed by Ansys-Fluent, under steady-state conditions.