Blade configuration and depth ratio impact on undershot waterwheel in compact irrigation for sustainable off-grid electrification

Undershot waterwheel turbines (USWWs) are promising renewable energy sources for off-grid electrification in developing countries, especially for low-head applications. This study aimed to compare the performance of wide-blade and large-diameter USWW designs for compact irrigation infrastructure. Two USWW configurations were tested: one with a large diameter and one with a wide blade. Numerical simulations using computational fluid dynamics were performed, and the results were validated with experimental data. The wide-blade design achieved significantly higher torque and power output than the large-diameter design did, demonstrating the importance of blade configuration for efficient energy transfer. This study also developed an empirical equation for the relationship between blade depth ratio and efficiency, highlighting the effect of this parameter on USWW performance. Finally, tip speed ratio and hydrostatic force were investigated, providing valuable insights into the hydraulic behavior of USWWs and their optimal operation. This study offers valuable insights for designing efficient and environmentally friendly USWWs for remote areas, paving the way for broader adoption of this renewable energy technology.