Numerical simulation of flow in hydro turbines channel to improve its efficiency by using of Lattice Boltzmann Method

摘要

The aim of the present work is to study the influence of channel geometry and its assemble gap on the efficiency improvement of hydro turbine. Raising flowing velocity and the control of the pressure drop of the inlet fluid of hydro turbines are the most important hydrodynamic factors for improving their efficiency. To study these and obtain the best hydrodynamic conditions of conducting channels, channels' simulations in seven different geometrical shapes and four different assemble gabs (1, 1.25, 1.5 and 2 m) using of Lattice Boltzmann Method (LBM) were carried out. The simulation indicates that using a conducting channel which hydro turbine is installed inside can play a significant role in turbine efficiency. In addition, the type of the channel shape and assemble gap have different effects on the flow parameters such as velocity and pressure drop, and consequently can have different effects on hydro turbine efficiency too. Considering the velocity ratio and the pressure drop, it is possible to select the Airfoil-like channel as the most efficient channel. Moreover, according to the illustrations, the stream in this channel is more stable than the other channels. Likewise, one-meter assemble gap was chosen as the most efficient one than the other ones. Therefore, Airfoil-like channel with one-meter assemble gap was considered as the best channel design for increase efficiency in hydro turbine constructions. (C) 2019 Elsevier B.V. All rights reserved.