Numerical analysis of lift-based in-pipe turbine for predicting hydropower harnessing potential in selected water distribution networks for waterlines optimization

The research models and simulates in-pipe turbine hydropower harnessing possibilities in water distribution networks of the sites under investigation considering in-pipe lift-based spherical turbine. The hydrofoil profile of the turbine is generated using National Advisory Committee for Aeronautics (NACA) aerofoil generator. Consequently, a Computer-Aided Design (CAD) model of the in-line lift-based spherical turbine is then developed and simulated, based on the peak and lean period of the volumetric discharge rates using commercial computational fluid dynamics software (Autodesk Simulation CFD®). The time series of power outputs are computed from the time series of discharge variations. A lift-based spherical turbine with NACA 0020 foil cross-section appears appropriate for extraction of energy in the water distribution pipelines. Furthermore, the minimum and maximum percentage head loss due to insertion of the turbine is about 1.94% at lean flow rates and 9.70% at the peaks for 250 mm pipelines. The available power was found out to depend on the density of the turbine blades material, flow rate, and the pipe diameter. The estimated lean and the peak electric power are about 415 and 1663 W, respectively, using aluminium foil blades while stainless steel foil produces about 242 and 1080 W in the 250 mm pipe.