Computational study of hydrodynamic performance of vertical axis water turbines

2012 ◽  
Author(s):  
Yang Sun ◽  
Liang Zhang
Keyword(s):  
Computational Study ◽  
Vertical Axis ◽  
Hydrodynamic Performance ◽  
Water Turbines

Mean Wave Drift Force on a Barge-Type Floating Wind Turbine With Moonpools

2021 ◽  
Author(s):  
Lei Tan ◽  
Tomoki Ikoma ◽  
Yasuhiro Aida ◽  
Koichi Masuda
Keyword(s):  
Wind Turbine ◽  
Vertical Axis ◽  
Offshore Wind ◽  
Hydrodynamic Performance ◽  
Vertical Axis Wind Turbine ◽  
Rotating Speed ◽  
Wave Drift ◽  
Floating Offshore Wind Turbines ◽  
Drift Force ◽  
Gyroscopic Effects

Abstract The barge-type foundation with moonpool(s) is a promising type of platform for floating offshore wind turbines, since the moonpool(s) could improve the hydrodynamic performance at particular frequencies and reduce the costs of construction. In this paper, the horizontal mean drift force and yaw drift moment of a barge-type platform with four moonpools are numerically and experimentally investigated. Physical model tests are carried out in a wave tank, where a 2MW vertical-axis wind turbine is modelled in the 1:100 scale. By varying the rotating speed of the turbine and the mass of the blades, the gyroscopic effects due to turbine rotations on the mean drift forces are experimentally examined. The wave diffraction and radiation code WAMIT is used to carry out numerical analysis of wave drift force and moment. The experimental results indicate that the influence of the rotations of a vertical-axis wind turbine on the sway drift force is generally not very significant. The predictions by WAMIT are in reasonable agreement with the measured data. Numerical results demonstrate that the horizontal mean drift force and yaw drift moment at certain frequencies could be reduced by moonpool(s).

scholarly journals Darrieus vertical-axis water turbines: deformation and force measurements on bioinspired highly flexible blade profiles

2020 ◽  
Vol 61 (6) ◽  
Author(s):  
Stefan Hoerner ◽  
Cyrille Bonamy ◽  
Olivier Cleynen ◽  
Thierry Maître ◽  
Dominique Thévenin
Keyword(s):  
Vertical Axis ◽  
Force Measurements ◽  
Water Turbines

scholarly journals Experimental and Computational Study of a Micro Vertical Axis Wind Turbine

2012 ◽  
Vol 49 ◽  
pp. 254-262 ◽  
Author(s):  
Abdulkadir Ali ◽  
Steve Golde ◽  
Firoz Alam ◽  
Hazim Moria
Keyword(s):  
Wind Turbine ◽  
Computational Study ◽  
Vertical Axis ◽  
Vertical Axis Wind Turbine

Investigation on Flow Characteristics and Performance of a Vertical Axis Wind Turbine With Deflector Plates

2019 ◽  
Author(s):  
K. Karthik Selva Kumar ◽  
Vinayak Kulkarni ◽  
Niranjan Sahoo
Keyword(s):  
Wind Turbine ◽  
Computational Study ◽  
Flow Characteristics ◽  
Vertical Axis ◽  
Vertical Axis Wind Turbine ◽  
Near Wake ◽  
Flow Phenomenon ◽  
Sliding Mesh ◽  
And Performance ◽  
Accelerated Flow

Abstract In this article, a 3D computational study has been performed to understand the flow phenomenon over the vertical axis wind turbine with a three-bladed NACA0021. The rotary motion of the VAWT simulated with sliding mesh techniques with reference to the SST-Kω turbulence model using the CFD software. The observed results were found to be having a significant improvement in the enhancement of the power output. Also, the investigation was move forwarded to understand the flow characteristics of the VAWT with the presence of deflector plates in different orientation at the upstream conditions. The present of deflector plates creates an augmented flow phenomenon which creates an accelerated flow at the near wake region, causing a significant improvement in the coefficient of power of the wind turbine.

6-DOF Numerical Simulation of the Vertical-Axis Water Turbine

2011 ◽  
Author(s):  
Xin Wang ◽  
Xianwu Luo ◽  
Baotang Zhuang ◽  
Weiping Yu ◽  
Hongyuan Xu
Keyword(s):  
Vertical Axis ◽  
Hydrodynamic Performance ◽  
Power Coefficient ◽  
Speed Ratio ◽  
Test Model ◽  
Tip Speed Ratio ◽  
Water Turbine ◽  
Tidal Stream ◽  
Static Head ◽  
Tidal Stream Turbine

Recent years, the vertical-axis water turbine (VAWT) is widely used for converting the kinetic energy of the moving water in open flow and with low static head like river and tidal sites. Conventional numerical methods such as disk-stream tube method and vortex panel method have some drawbacks to predict the behaviors and characteristics of the vertical-axis tidal stream turbine. This paper had treated the hydrodynamic performance of a VAWT model experimentally and numerically. Based on the present research, a 6-DOF method coupled with CFD suitable to simulate the rotor movement and predict the hydraulic performance for a VAWT was proposed. Compared with the experiments, the numerical results for the performance of the VAWT model were reasonable. It is also noted that there is a maximum power coefficient near tip speed ratio of 2.5 for the test model.

Numerical Investigation to Assess an Optimal Blade Profile for the Drag Based Vertical Axis Wind Turbine

2013 ◽  
Author(s):  
Sukanta Roy ◽  
Ujjwal K. Saha
Keyword(s):  
Renewable Energy ◽  
Wind Energy ◽  
Wind Turbines ◽  
Energy Demand ◽  
Computational Study ◽  
Flow Behavior ◽  
Renewable Energy Sources ◽  
Vertical Axis ◽  
Small Scale ◽  
Vertical Axis Wind Turbine

Rapid depletion rate of fossil fuels with an increasing energy demand and their high emission are imposing the evolution activities in the arena of renewable energy. To meet the future demands of renewable energy sources, wind energy is a very promising concept. In this feature, the drag based vertical axis wind turbines (VAWTs) are suitable for small scale wind energy generation for decentralized locations. However, these turbines have low power and torque coefficients as compared to other wind turbines. Numerous blade shapes have been proposed till now to improve the performance of these turbines. In the present paper, a computational study has been performed to simulate the air-flow over different blade profiles using shear stress transport (SST) k–ω turbulence model. The results obtained are validated with the available experimental data. In the dynamic simulations, the power and torque coefficients are calculated considering the blade arc angle as the variable shape parameter. The effects of drag and lift forces on the variable blade shapes are also studied in static simulations at various angular positions. The present paper tries to demonstrate an effective computational methodology to predict the flow behavior around a drag based VAWT. Through this study, it has been found possible to select an optimal blade shape from the point of its aerodynamic performance.

Sign in / Sign up

Export Citation Format

Share Document