Master Student , Alexandria University
Increasing the performance of Savonius turbine by using a novel blades which it designed by us.
The growing of energy nowadays is very notable particular which cares about the alternative energy when it comparing with the consuming one such as, fuels etc. Wind energy has the most common because it doesn’t have the effects of the burning results in our society which the fossil fuels have. Many Modifications have been studied in Savonius wind turbines (vertical axis wind turbine) particular in the blade shape to improve the power efficiency. The rotor blade modifications in this research numerically by using Ansys software and investigated by two ways which begging with three choices of combining blades between conventional and elliptical curves where the power efficiency increasing 5.41 %, 2.89 % and 5.47 % for those three blades, the other way it’s the blades created by using Fluent Adjoint solver where call it Adjoint blades and the percentage of increasing reached 14.7%, finely the efficiency rise up to 35.9% by a novel blade and it designed by modified the Adjoint blades. Moreover, the influence of shaft, overlap ration, and blades number carried out.
Abstract: In the quest for renewable energy sources, kinetic energy available in small water streams, river streams or human-made canals may provide new avenue which can be harnessed by using hydrokinetic turbines. Savonius hydrokinetic turbine is vertical axis turbine having drag based rotor and suitable for a lower flow velocity of the water stream. In order to enhance the efficiency of the turbine, this paper aims to analyze the performance of twisted blade Savonius hydrokinetic turbine. Using CFD analysis, an attempt has been made to optimize blade twist angle of Savonius hydrokinetic turbine. The simulation of a twisted Savonius hydrokinetic turbine having two blades has been carried out to investigate the performance. Commercial unsteady Reynolds-Averaged Navier-Stokes (URANS) solver in conjunction with realizable k-ε turbulence model has been used for numerical analysis. Fluid flow distributions around the rotor have been analyzed and discussed. It has been found that Savonius hydrokinetic turbine having a twist angle of 12.5° yields a maximum coefficient of power as 0.39 corresponding to a TSR value of 0.9 for a given water velocity of 2 m/s.
Pub.: 03 Mar '17, Pinned: 07 Jan '18
Abstract: The aim of our study is to project an optimized wind turbine Darrieus type capable to start at low wind speeds. This type of the turbine is characterized by a low starting torque compared with the Savonius rotor. To allow them, to operate for a long period, we consider a system enabling a self-start at low wind speeds. The study consist in three parts: first, a system of monitoring and control of the angle of attack that allows a self-starting at low wind speeds is presented, second part presents a general method for obtaining a profile with good starting torque and third part presents experimental study of the impacts of the angle of attack, the solidity and the wind velocity on the lift, grad forces and torque. The study continues to extend to other configurations namely that parabolic shape.
Pub.: 01 Jun '17, Pinned: 07 Jan '18