Investigation of Savonius turbines in terms of performance

In this thesis study, Savonius wind turbines, one of the vertical axis wind turbines that have been the subject of literature studies in recent years, have been examined in terms of performance. These turbines, which have many advantages over horizontal axis wind turbines, are mainly used to meet personal energy needs in rural and urban areas. The turbine blades of the vertical axis Savonius wind turbine have a lower efficiency compared to horizontal axis turbines because they produce both negative and positive torque during operation. In order to improve these low efficiencies, which are seen as a disadvantage in Savonius wind turbines, many innovative designs have been developed and therefore the performance of these turbines has been increased. It is possible to collect these innovative designs in two main design groups: in the form of structural design changes on the turbine and in the form of external design assemblies made outside the turbine, without making any changes to the shape of the classic Savonius wind turbine. Due to the fact that the performance studies of the Savonius wind turbine with structural design changes have been made quite extensively in the literature, in this thesis, the performance studies obtained with the additional external design devices of the Savonius wind turbine, especially in recent years, have been discussed. With this thesis, various exterior designs have been reviewed in a comprehensive way and information about current exterior design techniques has been provided. It has been determined that the turbine performances and thus the power coefficients have increased quite well with the external design techniques. It has been determined that the power coefficient values of Savonius wind turbines are between 0,054 and 0,400 with structural design changes. It has been determined that these power coefficient values have been increased at various levels up to 0,520 levels with additional external design devices. These external designs, which are used to increase the wind speed and reduce the negative torque generated in the Savonius wind turbine, have been discussed in detail. Thus, with this thesis study, a systematic reference for Savonius wind turbines, which have been of great interest in recent years, is presented.