CFD investigation of unsteady three-dimensional savonius hydrokinetic turbine in irrigation channel with varying positions for hydro power application

2021 ◽  
Author(s):  
C. M. Shashikumar ◽  
Vijaykumar Hindasageri ◽  
Vasudeva Madav
Keyword(s):  
Three Dimensional ◽  
Hydro Power ◽  
Irrigation Channel ◽  
Hydrokinetic Turbine ◽  
Power Application

Performance study of twisted Darrieus hydrokinetic turbine with novel blade design

2021 ◽  
pp. 1-37
Author(s):  
Mabrouk Mosbahi ◽  
Mouna Derbel ◽  
Mariem Lajnef ◽  
Bouzid Mosbahi ◽  
Zied Driss ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Maximum Power ◽  
Power Coefficient ◽  
Speed Ratio ◽  
Small Scale ◽  
Performance Study ◽  
Hydrokinetic Turbine ◽  
Blade Shape ◽  
Water Turbine ◽  
Water Canals

Abstract Twisted Darrieus water turbine is receiving growing attentiveness for small-scale hydropower generation. Accordingly, the need for raised water energy conversion incentivizes researchers to focalise on the blade shape optimization of twisted Darrieus turbine. In view of this, an experimental analysis has been performed to appraise the efficiency of a spiral Darrieus water rotor in the present work. To better the performance parameters of the studied water rotor with twisted blades, three novel blade shapes, namely U-shaped blade, V-shaped blade and W-shaped blade, have been numerically tested using a computational fluid dynamics three-dimensional numerical model. Maximum power coefficient of Darrieus rotor reaches 0.17 at 0.63 tip-speed ratio using twisted blades. Using V-shaped blades, maximum power coefficient has been risen up to 0.185. The current study could be practically applied to provide more effective employment of twisted Darrieus turbines and to improve the generated power from flowing water such as river streams, tidal currents, or other man made water canals.

Numerical Modeling and Optimization of Hydrokinetic Turbine

2011 ◽  
Author(s):  
Nitin Kolekar ◽  
Suchi Subhra Mukherji ◽  
Arindam Banerjee
Keyword(s):  
Numerical Modeling ◽  
Transient Analysis ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Turbulence Models ◽  
Coefficient Of Performance ◽  
Speed Ratio ◽  
Turbine Performance ◽  
Design Variables ◽  
Hydrokinetic Turbine

Hydrokinetic turbines, unlike conventional hydraulic turbines are zero head energy conversion devices which utilize the kinetic energy of flowing water for power generation. The basic operational principle of the horizontal axis hydrokinetic turbine (HAHkT) is same as the wind turbine, the only difference being change in working media: water instead of air. This paper discusses the hydrodynamic design of HAHkT via numerical modeling. Presently these turbines suffer from low coefficient of performance (Cp) which is governed by several design variables such as tip-speed ratio, chord distribution, solidity and number of blades. The numerical modeling is performed for both constant and varying chord geometries using commercially available computational fluid dynamics software (CFX/FLUENT) to understand the effect of each of the design variable on turbine performance. Since the flow Reynolds number is large (≥ 105), both one- and two-equation turbulence models are applied to solve Reynolds Averaged Navier Stokes equations. In addition, a three dimensional analysis of HAHkT is performed to give a better insight into the effect of tip vortices and flow separation phenomenon on turbine performance; the results are then compared with Blade Element Momentum (BEM) theory analysis. In addition, a procedure for a multivariate optimization scheme is discussed that aims at maximizing Cp for a constant flow velocity while maintaining optimum values of critical design variables listed above. Finally, the effect of variation of angle of attack on the flow around a hydrofoil is investigate using both static and transient analysis, the transient analysis being performed by subjecting the airfoil to periodic oscillations.

Numerical Analysis of Blockage Ratio Effect on a Portable Hydrokinetic Turbine

2016 ◽  
Author(s):  
Cosan Daskiran ◽  
Jacob Riglin ◽  
Alparslan Oztekin
Keyword(s):  
Free Stream ◽  
Numerical Study ◽  
Three Dimensional ◽  
Turbine Rotor ◽  
Power Coefficient ◽  
Stream Velocity ◽  
Blockage Ratio ◽  
Ratio Effect ◽  
Turbine Performance ◽  
Hydrokinetic Turbine

Three-dimensional steady state Computational Fluid Dynamics (CFD) analyses were performed for a pre-designed micro-hydrokinetic turbine to investigate the blockage ratio effect on turbine performance. Simulations were conducted using a physical turbine rotor geometry rather than low fidelity, simplified actuator disk or actuator lines. The two-equation k-ω Shear Stress Transport (SST) turbulence model was employed to predict turbulence in the flow field. The turbine performance at the best efficiency point was studied for blockage ratios of 0.49, 0.70 and 0.98 for three different free stream velocities of 2.0 m/s, 2.25 m/s and 2.5 m/s. Distinct blockage ratio results at a free stream velocity of 2.25 were compared to a previous numerical study incorporating the same rotor geometry within an infinite flowing medium. The pressure gradient between turbine upstream and turbine downstream for blocked channel flows elevated the turbine performance. The increment in blockage ratio from 0.03 to 0.98 enhanced power coefficient from 0.437 to 2.254 and increased power generation from 0.56 kW to 2.86 kW for the present study.

scholarly journals Design and numerical analysis of an efficient H-Darrieus vertical-axis hydrokinetic turbine

2019 ◽  
Vol 13 (4) ◽  
pp. 6036-6058
Author(s):  
Ramirez D. ◽  
Rubio-Clemente A. ◽  
E. Chica
Keyword(s):  
Rural Communities ◽  
Three Dimensional ◽  
Vertical Axis ◽  
Turbine Rotor ◽  
Power Coefficient ◽  
Stream Velocity ◽  
Ansys Fluent ◽  
Electrical Grid ◽  
2D Simulation ◽  
Hydrokinetic Turbine

Hydrokinetic turbines are one of the technological alternatives to generate and supply electricity for rural communities isolated from the national electrical grid with almost zero emission. The Darrieus turbine is one of the options that can be used as a hydrokinetic turbine due to its high power coefficient (Cp) and easy manufacture. In the present work, the design and hydrodynamic analysis of a Darrieus vertical-axis hydrokinetic turbine of 500 W was carried out. A free stream velocity of 1.5 m/s was used for the design of the blades. The diameter (D) and blade length (H) of the turbine were 1.5 m and 1.13 m, respectively. The blade profile used was NACA0025 with a chord length of 0.33 m and solidity () of 0.66. Two (2D) and three dimensional (3D) numerical analyses of the unsteady flow through the blades of the turbine were performed using ANSYS Fluent version 18.0, which is based on a Reynolds-Averaged Navier-Stokes (RANS) model. A transient 2D simulation was conducted for several tip speed ratios (TSR) using a k-ω Shear Stress Transport turbulence (SST) scheme. The optimal TSR was found to be around 1.75. Main hydrodynamic parameters, such as torque (T) and CP, were investigated. Additionally, 3 geometrical configurations of the turbine rotor were studied using a 3D numerical model in order to identify the best configuration with less Cp and T fluctuation. The maximum Cp average was 0.24 and the amplitude of Cp variation, near 0.24 for the turbine model with 3 blades of H equal to 1.13 m. On the other hand, for the turbine models with 6 and 9 blades of H equal to 0.565 m and 0.377 m, respectively, the maximum Cp averages were 0.51 and 0.55, respectively, and the amplitude of Cp variation, near 0.07 for the model with 6 blades and 0.17 for the model with 9 blades. This revealed that the hydrokinetic turbine with a geometrical configuration of 6 blades greatly improves the performance of the turbine due to this model has advantages compared to models with 3 and 9 blades, in terms of the reduction of their T curve fluctuation.

scholarly journals Sustainable Development around Small Scale Mining Areas by the Development of Micro Hydro Power: Application Cases in Cameroon

2020 ◽  
Vol 08 (03) ◽  
pp. 36-48 ◽  
Author(s):  
Fanyep Nana Antoine ◽  
Gubong Takam Charles Bertrand ◽  
Kengne Signe Elie Bertrand ◽  
Claudio J. C. Blanco
Keyword(s):  
Sustainable Development ◽  
Small Scale ◽  
Hydro Power ◽  
Mining Areas ◽  
Power Application

scholarly journals Pengujian Kincir Air Hidrokinetik Undershoot Di Irigasi Limau Manis Padang

2019 ◽  
Vol 12 (1) ◽  
pp. 1-5
Author(s):  
Ruzita Sumiati ◽  
Fardinal Fardinal ◽  
Nusyirwan Nusyirwan ◽  
Adriansyah Adriansyah ◽  
Robby Novrizal
Keyword(s):  
Renewable Energy ◽  
Power Plant ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Irrigation Canal ◽  
Irrigation Channel ◽  
Hydrokinetic Turbines ◽  
Hydrokinetic Turbine ◽  
Maximum Water ◽  
The Right

The power produced by a hydrokinetic turbine depends on the interaction between the rotor and water. Therefore, the optimal rotor geometry must be designed and built to capture maximum water energy and convert it into usable energy. Hydropower is one of the potential renewable energy that can contribute to the need for electricity. Hydropower generator is pollution free so this generator can answer environmental problems and the availability of renewable energy sources. The aim to be achieved in this study is to produce a turbine hydropower with good performance if it operates on an irrigation channel and is applied as a power plant. This research was developed to get the right specifications for the use of hydrokinetic turbines in the irrigation canal area. There are several methods carried out in the design of hydrokenetic turbines, namely by designing blades based on the shape of water flow, repairing the transmission system, and selecting the right generator. In this study, we tested the sweet lemon irrigate applied and tested in the area of ​​Padang Sumbar Sweet Limes Pauh, the results obtained were that the turbine can produce power of about 12.6 watts.

Numerical Modelling of Gravel Transport during Flushing Processes in an Alpine Reservoir

2020 ◽  
Author(s):  
Gabriele Harb ◽  
Josef Schneider
Keyword(s):  
Power Plants ◽  
Dynamic Balance ◽  
Three Dimensional ◽  
Suspended Sediments ◽  
Transport Processes ◽  
Bed Load ◽  
Shear Stresses ◽  
Hydro Power ◽  
Storage Volume ◽  
Initial Storage

<p>Sedimentation processes are in a “dynamic balance” in most natural rivers, but the construction of dams and reservoirs influences these natural conditions. The flow velocities, turbulences and bed shear stresses in reservoirs are reduced compared to free flow conditions, which lead to the deposition of the transported sediment particles. As a further consequence the sediment depositions reduce the storage volume by “filling up” the reservoir. This “reservoir sedimentation” is a problem in several Alpine reservoirs.</p><p>In the case of Alpine reservoirs with a small storage volume compared to the annual inflow, such as reservoirs of run-off river power plants, the water depth are usually lower than in reservoirs of storage and pump-storage hydro power plants. A larger part of the suspended sediments is thus transported through the reservoir and deposition of bed load fractions is the main problem. The deposition of coarse sediments at the head of the reservoir may cause problems regarding flood protection by raising the bed level and thus, raising the water level too.</p><p> </p><p>This contribution focus on the bed load transport processes during a flushing event in an Alpine reservoir. The reservoir is approximately 1 km long with an initial storage volume of about 250.000 m<sup>3</sup>. The annual bed load input is rather high, thus the remobilization of the sediment in the reservoir in case of flood events was investigated.</p><p>An open source three-dimensional numerical model with an internal coupled hydrodynamic and morphological part was used to simulate the flushing process. The calibration of the hydrodynamic model was done using ACDP measurements performed at the prototype to calibrate the roughness at the river bed. Additionally an extensive sensitivity analysis was carried out and several sediment transport formulae were tested.</p>

Simulation of the Water Hammer in a Hydro Power Plant Caused by Draft Tube Surge

2003 ◽  
Author(s):  
Albert Ruprecht ◽  
Thomas Helmrich
Keyword(s):  
Power Plant ◽  
Draft Tube ◽  
Three Dimensional ◽  
Water Hammer ◽  
Tube Flow ◽  
Three Dimensional Flow ◽  
Hydro Power ◽  
One Dimensional ◽  
Water Power ◽  
Dimensional Flow

The system oscillations of a water power plant caused by the draft tube flow in part load are investigated. A coupled simulation of a one-dimensional water hammer analysis and a three-dimensional flow calculation of the draft tube vortex rope is applied. With this approach the excitations of the oscillations, frequencies and amplitudes, have not to be estimated but are obtained from the simulation. This allows an accurate prediction of the system oscillations caused by draft tube surge.

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