A comparative study of turbulence models in a trapezoidal open channel for potential turbine installation site selection

Abstract

With large-scale projects being installed all over the world, the hydrokinetic (HK) sector has been considered as zero-head power scheme. When site conditions are adequate but ideal velocities are unavailable, choosing an installation location might be challenging. For identifying a potential hydrokinetic turbine (HKT) installation site, a comparative numerical assessment of various turbulence models is carried out at a trapezoidal open canal situated on the Tapi River, Surat, Gujarat, India. Various flow parameters, like longitudinal velocity along the depth and width, as well as secondary vectors, were utilized with different turbulence models, such as k–ɛ standard, k–ɛ renormalization group (RNG), k–ɛ realizable, k–ω standard and k–ω shear stress transport (SST). For predicting the potential HKT installation and understanding the flow physics phenomena, velocity vectors and water power density were analysed. The simulation results were validated using the experiments performed at the selected locations. Based on the error analysis, the k–ω SST model was found to be more accurate, providing the potential site for HKT installation. The potential site is capable enough to provide the flow velocity of 0.42 m/s, with an estimated power generation of 1.2 kW. The conclusion includes a more thorough comparison with deployed HKTs worldwide for the existing site.