A Comparative Study on Horizontal and Vertical Savonius Rotor Alignment for Efficient Energy Generation and Minimal Impact on Flow Condition

Authors: Manoj Sood, Upendra Bajpai, Sunil Kumar Singal

Abstract:

Extracting kinetic energy from small streams and canals in off-grid and remote areas offers a modern approach to energy generation using water current turbines. The Savonius water current turbine, a drag-based cross-flow turbine, is particularly suited for its self-starting characteristics at low flow velocities. This study numerically examines the impact of rotor alignment (horizontal vs. vertical) on the performance of the Savonius rotor and its impact on flow condition across velocities ranging from 0.5 to 2.0 m/s, with the tip speed ratio (TSR) maintained between 0.2 and 1.6. The Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations, along with a scalable wall function, has been solved to account for wall effects. Additionally, velocity and pressure contours are generated to analyze and discuss the wake recovery distance. The turbine’s performance is evaluated in terms of power coefficient and its influence on flow velocity. Results indicate that the horizontally aligned turbine demonstrates superior performance compared to the vertically aligned configuration. These findings provide valuable insights for researchers and industry professionals in selecting optimal turbine orientation for site-specific installations.

Keywords: Flow velocity, Savonius rotor, tip speed ratio, wake recovery distance.

References:

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