Numerical studies on the performance of a drag-type vertical axis water turbine for water pipeline

Pico-hydropower attracts much attention as a clean, reliable, and cost-efficient technology to generate electricity. Pico-hydropower systems are widely used in small rivers, aquacultures, irrigation systems, water supplies, and sewage systems. However, few studies have been conducted to investigate how to harness the excess energy in water supply systems (WSSs) in cities and towns. Previously, our research group developed several inline pico-hydropower systems for WSS which can supply power for monitoring sensor networks of water pipelines and maintenance services. In this paper, we have focused on the water turbine with a vertical 50% block water baffle for further analysis and optimization. We have carried out a combination of numerical and experimental investigations with the objective of improving the performance of this turbine at a velocity of 1.5 m/s-3.5 m/s and a rotational speed of 100 RPM-1000 RPM. The numerical results have been validated by the test results. A further optimization has been conducted through the numerical methods for the angle of water baffle and blade diameter. Also, we have presented the flow field in and around the water turbine to understand the power generation mechanism. Published by AIP Publishing.