An innovative design of INVELOX wind turbine: a numerical study on the effects of implementing long flange and Venturi holes

There is a global interest in renewable energy resources such as wind energy. INVELOX (increased velocity) is an innovative ducted wind turbine system. Some research has been performed to improve the efficiency of this machine by various geometrical modifications. Two ideas are presented and numerically analyzed in the present research to study their effects on the wind velocity when approaching the wind turbine, and consequently, on the wind turbine efficiency. In one of them, a relatively long flange is added to the original design, and in the other one, a pair of holes is considered in the venture to try to increase the mass flow rate of wind when reaching the turbine. Three various sizes of holes are studied here. The results reveal that using the long flange leads to an increment in the maximum wind velocity (about 15.45%) and more than 176% increase in the harvested power. In addition, the pair of holes in the Venturi with a diameter of 35 cm results in a slight improvement in the harvested power. For the first time, the turbine has been modeled inside the Venturi. A comparison between the results for the INVELOX, including the turbine, and that of the turbine in the free stream indicates that implementing INVELOX leads to 3.14 times more power generation.