scholarly journals Numerical Investigation of Three-Dimensional and Vortical Flow Phenomena to Enhance the Power Performance of a Wind Turbine Blade

2020 ◽  
Vol 11 (1) ◽  
pp. 72
Author(s):  
Jae-Ho Jeong ◽  
Kwangtae Ha
Keyword(s):  
Wind Turbine ◽  
Three Dimensional ◽  
Aerodynamic Performance ◽  
Vortical Flow ◽  
Intensity Level ◽  
Power Performance ◽  
Flow Angle ◽  
Vortical Flows ◽  
Investigation Methods ◽  
Blade Tip

The performance of a wind turbine generator (WTG) is highly dependent on the interaction of a rotor blade with complex fluid behaviors, especially the induced vortex structure. In this paper, vortical flows around a blade were first investigated by the unsteady Reynolds averaged Navier–Stokes (RANS) simulation with shear stress transport (SST) turbulence model. It showed that the vortical flows were strongly formed at the blade tip due to the 3D behavior of the boundary layers dominated by pressure gradient. The strong secondary flow was also formed at the near hub due to the Coriolis force and the centrifugal force. At the interacting region of the rotating blade with the tower, the power production was reduced by 22.1% due to the high-pressure fluctuation of the 3P frequency. Based on the close investigation, methods for enhancing the power performance of a WTG were explored, which included the optimization of winglet and ogee design for the blade tip and optimal layout of the nacelle anemometer. The optimized winglet achieved the increase of aerodynamic performance with 0.54%, and the optimal location of the nacelle anemometer was found with a low-turbulence intensity level of 0.003 normalized by the rotor tip speed. The results showed that the traditional anemometer needs to consider the intrinsic flow angle of 11.43° to avoid the loss of aerodynamic performance caused from yaw error.

Optimization of Aerodynamic Performance of Wind Turbine Blades

2013 ◽  
Vol 284-287 ◽  
pp. 518-522
Author(s):  
Hua Wei Chi ◽  
Pey Shey Wu ◽  
Kami Ru Chen ◽  
Yue Hua Jhuo ◽  
Hung Yun Wu
Keyword(s):  
Power Generation ◽  
Wind Turbine ◽  
Turbine Blades ◽  
Three Dimensional ◽  
Aerodynamic Performance ◽  
Wind Power Generation ◽  
Generation System ◽  
Wind Turbine Blades ◽  
Rotor Design ◽  
Power Generation System

A wind-power generation system uses wind turbine blades to convert the kinetic energy of wind to drive a generator which in turn yields electricity, the aerodynamic performance of the wind turbine blades has decisive effect on the cost benefit of the whole system. The aerodynamic analysis and the optimization of design parameters for the wind turbine blades are key techniques in the early stage of the development of a wind-power generation system. It influences the size selection of connecting mechanisms and the specification of parts in the design steps that follows. A computational procedure and method for aerodynamics optimization was established in this study for three-dimensional blades and the rotor design of a wind turbine. The procedure was applied to improving a previously studied 25kW wind turbine rotor design. Results show that the aerodynamic performance of the new three-dimensional blades has remarkable improvement after optimization.

scholarly journals Efficient contribution of partially tip cascaded horizontal-axis wind turbine

2019 ◽  
Vol 11 (11) ◽  
pp. 168781401989211
Author(s):  
Deyaa Nabil Elshebiny ◽  
Ali AbdelFattah Hashem ◽  
Farouk Mohammed Owis
Keyword(s):  
Wind Turbine ◽  
Aerodynamic Performance ◽  
Operating Conditions ◽  
Horizontal Axis ◽  
National Renewable Energy Laboratory ◽  
Horizontal Axis Wind Turbine ◽  
Ansys Fluent ◽  
Knowing That ◽  
Turbine Performance ◽  
Blade Tip

This article introduces novel blade tip geometric modification to improve the aerodynamic performance of horizontal-axis wind turbine by adding auxiliary cascading blades toward the tip region. This study focuses on the new turbine shape and how it enhances the turbine performance in comparison with the classical turbine. This study is performed numerically for National Renewable Energy Laboratory Phase II (non-optimized wind turbine) taking into consideration the effect of adding different cascade configurations on the turbine performance using ANSYS FLUENT program. The analysis of single-auxiliary and double-auxiliary cascade blades has shown an impact on increasing the turbine power of 28% and 76%, respectively, at 72 r/min and 12.85 m/s of wind speed. Knowing that the performance of cascaded wind turbine depends on the geometry, solidity and operating conditions of the original blade; therefore, these results are not authorized for other cases.

Prediction of Ice Accretion on Wind Turbine with Numerical Method

2012 ◽  
Vol 512-515 ◽  
pp. 754-757
Author(s):  
Xian Yi ◽  
Kai Chun Wang ◽  
Hong Lin Ma
Keyword(s):  
Wind Turbine ◽  
Numerical Method ◽  
Collection Efficiency ◽  
Three Dimensional ◽  
Horizontal Axis ◽  
Ice Accretion ◽  
Horizontal Axis Wind Turbine ◽  
Blade Tip ◽  
Computer Codes ◽  
Multiple Reference

A three dimensional numerical method and its computer codes, which are suitable to predict the process of horizontal axis wind turbine icing, are presented. The method is composed of the Multiple Reference Frame (MRF) method to calculate flowfield of air, an Eulerian method to compute collection efficiency and a three dimensional icing model companying with an iterative arithmetic for solving the model. Ice accretion on a 1.5 MW horizontal axis wind turbine is then computed with the numerical method, and characteristics of droplet collection efficiency and ice shape/type are obtained. The results show that ice on the hub and blade root is slight and it can be neglected comparing with ice near blade tip. From blade tip to root, ice becomes thinner and glaze ice may changes into rime ice.

The Effect of Distributed Roughness on the Power Performance of Wind Turbines

2010 ◽  
Author(s):  
G. Pechlivanoglou ◽  
S. Fuehr ◽  
C. N. Nayeri ◽  
C. O. Paschereit
Keyword(s):  
Steady State ◽  
Wind Tunnel ◽  
Numerical Simulations ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Power Production ◽  
Aerodynamic Performance ◽  
Power Performance ◽  
Turbine Performance ◽  
Wind Tunnel Measurements

The effects of distributed roughness on wind turbines are extensively investigated in this paper. The sources of roughness are identified and analyzed and their effects on airfoil are estimated from simulations and measured with wind tunnel measurements. In addition to the environmental and manufacturing induced roughness, several forms of roughness-related shape deviations are investigated and their effects on the aerodynamic performance of airfoils is qualitatively predicted through numerical simulations. The actual effects of roughness on wind turbine performance are also presented through power production measurements of wind turbines installed in sandy environments. These measurements are correlated with simulated power predictions, utilizing a steady state BEM code.

scholarly journals Design of Wind Turbine Blade with Thick Airfoils and Flatback and its Aerodynamic Characteristic

2015 ◽  
Vol 9 (1) ◽  
pp. 910-915 ◽  
Author(s):  
Lijun Xu ◽  
Lei Xu ◽  
Lei Zhang ◽  
Ke Yang
Keyword(s):  
Wind Turbine ◽  
Power Output ◽  
Aerodynamic Characteristic ◽  
Aerodynamic Performance ◽  
Parameter Design ◽  
Speed Ratio ◽  
Original Design ◽  
Tip Speed Ratio ◽  
Blade Tip ◽  
The Relationship

large-scaled blade has posed many problems related to design and production. After introducing the features of blade with thick airfoils and flatback, based on relevant parameters of Huaren 100 kW wind turbine, the paper designed blade with thick airfoils and flatback, introduced blade parameter design, and analyzed the aerodynamic performance of blades using GH bladed software, obtaining the relationship between power output of wind turbine with blade tip speed ratio Cp. Furthermore, it analyzed the aerodynamic performance of original design blades, modified blades and Huaren 100 kW blades, and assessed the aerodynamic performance of modified blade.

scholarly journals Evaluation of Wind Flow Characteristics by RANS-Based Numerical Site Calibration (NSC) Method with Met-Tower Measurements and Its Application to a Complex Terrain

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5121 ◽  
Author(s):  
Jae-ho Jeong ◽  
Kwangtae Ha
Keyword(s):  
High Resolution ◽  
Wind Turbine ◽  
Complex Terrain ◽  
Cfd Simulation ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Vortical Flow ◽  
Wind Flow ◽  
Rans Simulation ◽  
Resolution Scheme

The performance of wind turbines is not only dependent on the wind turbine design itself, but is also dependent on the accurate assessment of wind resources at the installation site. In this paper, the numerical site calibration (NSC) method using three-dimensional Reynolds-averaged Navier–Stokes (RANS) simulation was proposed to accurately forecast the wind flow characteristics of wind turbine sites with complex terrains, namely Methil in Scotland, and Haenam in South Korea. From NSC at the Methil and Haenam sites, it was shown that the complicated and vortical flow fields around hills and valleys were captured using the three-dimensional RANS CFD simulation in Ansys CFX software based on a high-resolution scheme with a renormalization group (RNG)-based k-ε turbulence model. It was also shown that topographically induced wind profile and turbulence intensity over a local-scale complex terrain are remarkably dominated by flow separation after passing hills. It was concluded that the proposed NSC method using three-dimensional RANS simulation with a high-resolution scheme was an economically useful method for evaluating wind flow characteristics numerically to assess wind turbine sites with complex terrains and designing the wind farm layout.

Numerical Study of Effects of AJVG on Aerodynamic Performance and Speed Control of Small-Scale Fixed-Pitch HAWT

2014 ◽  
Author(s):  
Xiang Gao ◽  
Jun Hu ◽  
Zhiqiang Wang ◽  
Chenkai Zhang
Keyword(s):  
Flow Field ◽  
Wind Turbine ◽  
Output Power ◽  
Vortex Generator ◽  
Speed Control ◽  
Aerodynamic Performance ◽  
Small Scale ◽  
Air Jet ◽  
Blade Tip ◽  
Fixed Pitch

Due to the feature of structure simplicity, lower production cost and maintenance ease, fixed pitch variable speed wind turbine has been widely used in non-grid-connected wind power systems. The calculation of wind turbine performance plays an important part in the design of wind turbines. Aerodynamic performance calculation is particularly significant in the fixed pitch stall-regulated wind turbine aerodynamic design process. To enhance the output power and power coefficient of wind turbine, active flow control technologies such as vortex generator are adopted in recent years. In this paper, a small wind turbine with air jet vortex generator (AJVG) on the blade tip is designed, and the output power of the wind turbine gets changed by operating the air jet. Computational Fluid Dynamics method is chosen to obtain aerodynamic characteristics of the wind turbine with/without AJVG and these features are furtherly integrated with speed control method to get speed control strategy under full-speed circumstance. It can be found after complete comparison that through setting AJVG at the blade tip, the new speed control features can help make it operate more stably in a wide range of wind speed without changing the existing wind turbine blades profiles and pitch angle. Also details of the flow field are obtained when solving the three-dimensional Navier-Stokes Equations. By analyzing the flow field of wind turbine with/without AJVG, the influence mechanism of the AJVG is demonstrated in this paper.

Three Dimensional Modeling and Aerodynamic Analysis of MW Wind Turbine Blade

2011 ◽  
Vol 305 ◽  
pp. 274-278
Author(s):  
Hong Pan ◽  
Wen Lei Sun ◽  
Lian Ying He
Keyword(s):  
Wind Turbine ◽  
Turbine Blade ◽  
Three Dimensional ◽  
Aerodynamic Performance ◽  
Wind Turbine Blade ◽  
Transformation Theory ◽  
Aerodynamic Analysis ◽  
Blade Element Theory ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling

Wind turbine blade is one of the key components of wind turbine, and its aerodynamic performance largely determine the reliability of wind turbine. This paper use the momentum - blade element theory, and correction by Prandtl, Wilson correction, Glauert correction and other methods to modify the model of the blade to come to the aerodynamic model, then using the point of the coordinate transformation theory each the airfoil two dimensional coordinate will conversion into space coordinates, using UG of three-dimensional modeling software to model, and finally the aerodynamic performance of airfoil is analyzed. Through modeling and aerodynamic analysis, for the following structure optimization and control strategy laid a foundation.

Navier–Stokes Analysis of Turbine Blade Heat Transfer and Performance

1992 ◽  
Vol 114 (4) ◽  
pp. 795-806 ◽  
Author(s):  
D. J. Dorney ◽  
R. L. Davis
Keyword(s):  
Heat Transfer ◽  
Turbine Blade ◽  
Three Dimensional ◽  
Numerical Approach ◽  
Aerodynamic Performance ◽  
Navier Stokes ◽  
Approximate Factorization ◽  
Absolute Level ◽  
Flow Angle ◽  
And Performance

A three-dimensional Navier–Stokes analysis of heat transfer and aerodynamic performance is presented for a low-speed linear turbine cascade. The numerical approach used in this analysis consists of an alternate-direction, implicit, approximate-factorization, time-marching technique. An objective of this investigation has been to establish the computational grid density requirements necessary to predict blade surface and endwall heat transfer accurately, as well as the exit plane aerodynamic total pressure loss and flow angle distributions. In addition, a study has been performed to determine the importance of modeling transition as well as a viable implementation strategy for the three-dimensional turbulence model in the turbine blade passage. Results are presented demonstrating that the present procedure can accurately predict three-dimensional turbine blade heat transfer as well as the absolute level and spanwise distribution of aerodynamic performance quantities.

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