Faculty Publications
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Item Numerical studies on the performance of Savonius hydrokinetic turbines with varying blade configurations for hydropower utilization(Elsevier Ltd, 2024) Shanegowda, T.G.; Shashikumar, C.M.; Gumtapure, V.; Madav, V.Hydrokinetic turbines harness the kinetic energy of flowing water to generate sustainable power, offering a promising avenue for clean and renewable energy. An effective turbine design is necessary for optimizing power extraction even in scenarios with minimal head. Among the various hydrokinetic turbine designs, the Savonius hydrokinetic turbine holds prominence. Over the past century, numerous studies have aimed to refine the design of the Savonius rotor, yet there remains no consensus on the ideal configuration for these turbines. Addressing this, the current study introduces a novel approach with detailed 3D transient simulations to enhance the water turbine performance via blade modifications, transitioning from traditional analyses that primarily focus on wind turbines. This research develops and analyzes five unique turbine geometries, each varying in blade number, diameter, and angular positions. A detailed numerical analysis was conducted using the sliding mesh technique to assess their impact on turbine efficiency and output, using an inlet water velocity of 0.5 m/s and a tip speed ratio ranging from 0.7 to 1.3. Findings indicate that a two-blade turbine configuration achieves the highest torque coefficient of 0.295, which is 2.41 times higher than that of a four-bladed design with equal blade diameter at a tip speed ratio of 0.7. It also reaches a maximum power coefficient of 0.217, marking a 155 % increase over four-bladed designs with equal blade diameter at a tip speed ratio of 0.9. © 2024 Elsevier LtdItem Comprehensive analysis of blade geometry effects on Savonius hydrokinetic turbine efficiency: Pathways to clean energy(Elsevier Ltd, 2024) Shanegowda, T.G.; Shashikumar, C.M.; Gumtapure, V.; Madav, V.The rising global demand for clean and renewable energy has intensified interest in hydrokinetic energy harvesting, with Savonius turbines gaining attention due to their simplicity and low cost. While numerous studies have focused on refining blade designs for wind turbines, limited research has been conducted on water turbines to identify the best design. This study investigates the effect of blade geometry on the efficiency of Savonius hydrokinetic turbines to identify the optimal configuration. Three new blade designs were tested, incorporating inner blades and varying blade numbers. These designs were experimentally evaluated to identify the optimal turbine configuration for maximum efficiency, and the findings were then validated through numerical studies. Rotational analysis was conducted to investigate torque variations across a full turbine rotation from 0° to 360°, and flow characteristic analysis was performed by utilizing pressure and contour plots at critical positions, including 0°, minimum torque coefficient (CT Min), and maximum torque coefficient (CT Max). Results indicate that the 2-blade Savonius turbine achieved the highest efficiency, with a maximum torque coefficient of 0.29 and a power coefficient of 0.22. It demonstrated 63.5 % greater power efficiency compared to the 3-Blade Savonius Turbine, 2.65 times greater than the Segmented Quarter Savonius Turbine, and 2.26 times greater than the Concentric Arc Savonius Turbine. These findings highlight the importance of blade geometry optimization in improving the performance of Savonius turbines for efficient hydrokinetic energy generation. © 2024 The AuthorsItem Numerical analysis of Savonius hydrokinetic turbine performance in straight and curved channel configurations(Elsevier Ltd, 2025) T G, S.; Shashikumar, S.; Gumtapure, V.; Madav, V.The global shift towards renewable energy has driven research into efficient hydrokinetic energy harvesting, particularly using Savonius turbines for their simplicity and adaptability to low-flow environments. While previous studies have focused primarily on straight channels, the impact of channel bends, commonly found in agricultural canals, rivers, and irrigation channels, remains underexplored. The present 3D transient numerical study addresses this gap by investigating the performance of Savonius hydrokinetic turbines in channels with 30°, 60°, and 90° bends, evaluating their efficiency under varying flow conditions. The research aims to evaluate the impact of these channel bends on key performance parameters such as the tip speed ratio (TSR), torque coefficient (CT) and power coefficient (CP), supported by detailed pressure and velocity contour analyses. The turbine positioned in the 30° bend emerged as the most efficient configuration, achieving a CTmax of 0.29 at 0.7 TSR and CPmax of 0.24 at 1.0 TSR. The 60° and 90° bends exhibited efficiency reductions of 15 % and 30 %, respectively, due to adverse pressure gradients and increased turbulence. Velocity contour plots demonstrated reduced wake regions and optimized flow reattachment for the 30° bend, while pressure contour analysis indicated lower drag forces on the advancing blades. This study highlights the potential of using Savonius turbines in agricultural channels, recommending the 30° bend as the optimal channel configuration to maximize turbine efficiency, providing a sustainable solution for energy generation in rural and low-flow environments. © 2025
