MODELLING AND SIMULATION OF SAVONIUS-GORLOV HYBRID HYDROKINETIC TURBINE

Abstract

The development of a nation is strongly attributed towards its energy demand and production. The present scenario seeks the high energy demand and eventually high energy production. On large scale, this demand is generally met by using the fossil fuels which are proven to be harmful to the environment. In order to preserves the environment and simultaneously fulfil the energy requirement, use of renewable energy is encouraged since last few years. Several renewable energy sources are abundantly available across the world such as solar, Wind, Hydro, Biomass, Ocean and Geothermal. India is bestowed with many rivers and their tributaries that provide water for the livelihood of many people. The conventional hydropower plants are based on the available head of water viz. potential energy of water. In the flowing rivers, the natural head sites are rarely available and most of the artificial head based feasible sites have already been exploited. However, due to flow in the rivers, canals and other manmade channels, sufficient kinetic energy based potential sites are available which can be harnessed. This kinetic energy can be harnessed by using the hydrokinetic turbine. Since, these turbines do not require the potential head, therefore, these turbines can also be termed as zero head turbines. Under the present dissertation work, an extensive literature review has been carried out on the current energy scenario and different available hydrokinetic technology. In order to tackle the energy demand and with minimal environment impact, a hybrid hydrokinetic turbine systems is proposed which is the combination of two conventional Savonius and Gorlov hydrokinetic turbine. The present study deals with the performance evaluation of hybrid turbine under different operating conditions. The numerical investigations are performed by using a commercially available ANSYS software with CFX solver. The computational domain was modelled to resemble the deployment of hybrid hydrokinetic turbine in the channel. The water having the flow velocity of 1.0 m/s/ is considered and different operating conditions were maintained by using the variable RPM by changing the TSR value. Power and torque coefficient parameters are considered to evaluate the performance of the turbine and maximum power coefficient of turbine was reported as 0.144 which is corresponding the TSR value of 1.0. Further, maximum torque coefficient as 0.175 is observed corresponding to 0.6 value of TSR. The flow field variations near the turbine along with in computational domain were visualized by using the pressure and velocity contours.