The Influence of Zigzag Position on The Concave Surface of a Savonius Turbine on Its Performance

Abstract

One potential strategy for reducing carbon dioxide (CO₂) emissions from fossil fuel consumption is the adoption of renewable energy sources. One of these green sources is wind energy, which is captured by wind turbines. The Savonius wind turbine, a vertical-axis wind turbine, was designed for small-scale energy conversion and is especially right for Indonesia's low wind speeds. This study aims to investigate the influence of the zigzag position applied to the concave blade on the performance of the Savonius turbine. This objective was accomplished through the application of 3D computational fluid dynamics simulations, conducted at a tip-speed ratio of 0.6, a zigzag height of 2 mm, and velocity (U) of 5 meter per second. Based on the results of numerical analysis, the data obtained for turbines with the full zigzag model (model 1) and the zigzag at the blade tip model (model 2) show higher maximum moment data compared to the model with the zigzag in the middle of the blade (model 3), namely 0.06 Nm for model 1, 0.052 Nm for model 2, and 0.036 Nm for model 3. However, model 3 exhibits more stable rotation due to its smaller torque amplitude and lack of negative moment.