Hadi Motawej - School of Mechanical Engineering, Iran University of Science & Technology, Tehran, Iran
Mahdi Moghimi - School of Mechanical Engineering, Iran University of Science & Technology, Tehran, Iran

Wind is considered as one of the renewable and clean energy resources. Horizontal and vertical axis wind turbines (VAWTs) are used for power generation. VAWTs are appropriate for operating under low speed wind to produce power in a small-scale manner. However, to improve performance in such a situation, many VAWT designs have been developed. In this paper, we aim to develop a low-cost model for evaluating the aerodynamic design and performance of Gorlov vertical axis wind turbine (VAWT). To this end, a double multiple stream tube (DMST) model, which is based on the blade element momentum theory (BEM) has been developed for Gorlov VAWTs. The developed model is validated by comparing the obtained results with the available results in the literature; in addition, overall evaluation on the effects of geometrical parameters, including number of blades, helical angle, chord length and aspect ratio have been performed for aerodynamic performance and the torque coefficient curves of Gorlov VAWT. Considering the results of parametrical evaluation on Gorlov turbine, it becomes evident that the number of blades and helical angle are important parameters in reducing the aerodynamic loads and improving the rotor stability. As the blade chord length or aspect ratio increases, the performance improves at low tip speed ratio ( ) values; however, it decrease at high values and peak power coefficient ( ). Moreover, self-starting behavior has been improved with increasing the blade chord length.

VAWT, Gorlov, DMST, Wind energy, Aerodynamic performance