Executive Summary : | Adaptive or morphing structure plays a vital role on modifying the magnitude of drag and lift acting on the structure. One of the objectives of this proposed work is to carry out thorough computational analysis of the complex flow characteristics past morphing blades of rotating savonius turbine. Vertical axis wind turbines (VAWTs) are suitable for low wind speed applications. savonius type VAWT has many advantages. Moreover VAWTs are can be used where horizontal axis wind turbines are not suitable. But, when compared to horizontal axis wind turbines, VAWT shows low performance measured in terms of power coefficient (Cp). The Cp value of VAWT will be the maximum if the drag on the returning-blade is ideally reduced to zero. Methods to reduce the drag on the returning-blade are available in literature. We have conducted research on various methods to improve the performance of savonius type VAWT and the results are published as listed in section - 4.3. In the past study, we have taken blades of different shapes, but all are rigid. We have also considered pivoted blades which are free to move without any control. This pivot mechanism is dominated by the centrifugal force of the rotating blades even at low rotational speed. Therefore, pivoted blades are not appropriate solution to reduce drag on the returning blade. In this proposed project, the innovative morphing blades will be subjected to continuously controlled shape change. The instantaneous shape of the blade will be based on its position relative to wind direction. These morphing blades lead to performance enhancement of the savonius type VAWT. To the best of our knowledge, the proposed savonius turbine fitted with morphing blades is new and such concept is not reported in literature. In-depth details of flow characteristics captured from computational study will be used to design the morphing blades. Control of shape or geometry of the blades with respect to its angular position will be based on the computational results. Indigenous test facility will be developed in-house to carry out experimentation. The proof of concept will be established. Working model of savonius type VAWT fitted with adaptive or morphing blades will be delivered. |