Study on the influence of an axial distance between rotors on a performance of a small counter-rotating wind turbine

Abstract

In this paper, results of the investigation on the performance of a small counter-rotating wind turbine has been presented. Computational Fluid Dynamics methods have been used for wind turbine simulations. Rotors representation were introduced into computational domain by means of Actuator Line Model. Influence of an axial distance of CRWT rotors has been investigated. In all studied configurations rotors were counter-rotating with exactly the same rotational speed. Results of a study revealed noticeable increase in power coefficient for optimal configuration. Dynamic interaction between rotors has been investigated exposing significant interference in both torque and power in part of considered cases. Reasonable rotors distances, as well as rotors placements on tower's sides have been proposed. Used calculation method has been found to be appropriate for counter-rotating wind turbine simulation.