Design and Analysis of a Large-Scale Positive Displacement Vane Pump for Wind Tower Application

An innovative combined hydraulic and gear-train power transmissions system for Mega-Watt scale wind turbines is proposed herein. The proposed concept targets large-scale wind turbines for an efficient and reliable conversion of the mechanical power of the rotating blades to electrical power. The novel hybrid system presented in this approach takes advantage of the benefits of both hydraulic and conventional gearbox systems, without introducing their potential inherent undesirable attributes at large scale. The proposed design first converts the mechanical power of the turbine blades to hydraulic power at a relatively high-pressure (about 2,500 psi) under a relatively low-speed (about 4 in/sec). The hydraulic fluid exiting the discharge port of the low-speed hydraulic pump is branched out into plurality of hydraulic lines for the purpose of dividing the total mechanical power of the wind turbine into multitude of lower hydraulic power lines. Each hydraulic line then delivers its hydraulic power into the corresponding intake port of a hydraulic motor having a low-speed-high-torque output shaft. The output shaft of each of the hydraulic motors then drives the input shaft of a mechanically matched gearbox to increase the rotary speed. Finally, the high-speed output shaft of each gearbox (about 1800 RPM) drives a corresponding matched electric generator. A preliminary design for a variable displacement vane pump has been proposed in this paper. This work includes a theoretical analysis of the overall efficiency of the system. The combined volumetric, mechanical, and overall efficiency of a typical proposed system was shown to be about 98%.

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Scaling 3D Low-Pressure Turbine Blades for Low-Speed Testing

Volume 2B: Turbomachinery ◽

10.1115/gt2015-42176 ◽

2015 ◽

Author(s):

Matteo Giovannini ◽

Michele Marconcini ◽

Filippo Rubechini ◽

Andrea Arnone ◽

Francesco Bertini

Keyword(s):

Turbine Blade ◽

High Speed ◽

Large Scale ◽

Mechanical Design ◽

General Procedure ◽

Turbine Blades ◽

Low Pressure ◽

Low Speed ◽

Open Rotor ◽

Inlet Conditions

The present activity was carried out in the framework of the Clean Sky European research project ITURB (“Optimal High-Lift Turbine Blade Aero-Mechanical Design”), aimed at designing and validating a turbine blade for a geared open rotor engine. A cold-flow, large-scale, low-speed (LS) rig was built in order to investigate and validate new design criteria, providing reliable and detailed results while containing costs. This paper presents the design of a LS stage, and describes a general procedure that allows to scale 3D blades for low-speed testing. The design of the stator row was aimed at matching the test-rig inlet conditions and at providing the proper inlet flow field to the blade row. The rotor row was redesigned in order to match the performance of the high-speed one, compensating for both the compressibility effects and different turbine flow paths. The proposed scaling procedure is based on the matching of the 3D blade loading distribution between the real engine environment and the LS facility one, which leads to a comparable behavior of the boundary layer and hence to comparable profile losses. To this end, the datum blade is parameterized, and a neural-network-based methodology is exploited to guide an optimization process based on 3D RANS computations. The LS stage performance were investigated over a range of Reynolds numbers characteristic of modern low-pressure turbines by using a multi-equation, transition-sensitive, turbulence model.

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A Coupled CFD/Multibody Dynamics Analysis Tool for Offshore Wind Turbines With Aeroelastic Blades

Volume 10: Ocean Renewable Energy ◽

10.1115/omae2017-61062 ◽

2017 ◽

Cited By ~ 1

Author(s):

Yuanchuan Liu ◽

Qing Xiao ◽

Atilla Incecik

Keyword(s):

Wind Turbine ◽

Multibody Dynamics ◽

Wind Turbines ◽

Large Scale ◽

Turbine Blades ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Analysis Tool ◽

Dynamics Analysis ◽

Offshore Wind Turbines

Aero-elasticity is an important issue for modern large scale offshore wind turbines with long slender blades. The behaviour of deformable turbine blades influences the structure stress and thus the sustainability of blades under large unsteady wind loads. In this paper, we present a fully coupled CFD/MultiBody Dynamics analysis tool to examine this problem. The fluid flow around the turbine is solved using a high-fidelity CFD method while the structural dynamics of flexible blades is predicted using an open source code MBDyn, in which the flexible blades are modelled via a series of beam elements. Firstly, a flexible cantilever beam is simulated to verify the developed tool. The NREL 5 MW offshore wind turbine is then studied with both rigid and flexible blades to analyse the aero-elastic influence on the wind turbine structural response and aerodynamic performance. Comparison is also made against the publicly available data.

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Modeling and Experimental Study of a Novel Power Split Hydraulic Transmission

BATH/ASME 2018 Symposium on Fluid Power and Motion Control ◽

10.1115/fpmc2018-8921 ◽

2018 ◽

Author(s):

Haoxiang Zhang ◽

Feng Wang ◽

Bing Xu

Keyword(s):

Flow Rate ◽

Experimental Studies ◽

Friction Torque ◽

Output Shaft ◽

Mechanical Power ◽

Vane Pump ◽

Input Shaft ◽

Power Split ◽

Outlet Flow ◽

Shaft Torque

The characteristics of a novel power split hydraulic transmission are studied in this paper. The new hydraulic transmission is built from a balanced vane pump with a floating ring. By coupling the floating ring to the output shaft, it becomes a hydraulic transmission, converting the mechanical power on the input shaft into the hydraulic power at the outlet and the mechanical power on the output shaft. By controlling the pressure at the outlet (control pressure), the power ratio transferred through mechanical and hydraulic path can be adjusted. One important feature of the new transmission is that the internal friction torque of the transmission, e.g., friction torque between vane tips and floating ring, helps to drive the output shaft whereas is wasted and turned into heat in a conventional vane pump. This increases the transfer efficiency from input shaft to output shaft. In this study, the characteristics of the input shaft torque, output shaft torque and the outlet flow rate are investigated through experimental studies. Results show that the shaft torques and the outlet flow rate are functions of control pressure and differential shaft speed. The mathematical models have been developed from the analytical and experimental results. The study provides a comprehensive understanding of the new transmission.

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Structural Optimization on Composite Blades of Large-Scale Wind Turbines

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.958 ◽

2013 ◽

Vol 284-287 ◽

pp. 958-962

Author(s):

Kun Nan Chen ◽

Wei Hsin Gau

Keyword(s):

Wind Turbine ◽

Turbine Blade ◽

Wind Turbines ◽

Large Scale ◽

Turbine Blades ◽

Weight Ratio ◽

Spanwise Direction ◽

Second Phase ◽

Wind Turbine Blades ◽

Composite Blade

Turbine blades used in large-scale, horizontal-axis wind turbines are usually made from composite materials to reduce the weight while attaining a reasonable strength to weight ratio. The design of large wind turbine blades must consider both their aerodynamic efficiency and structural robustness. This paper presents an optimum design scheme for composite wind turbine blades. The first optimization phase produces the aerodynamic outer shape of a blade framed by airfoils with optimum cord lengths and twist angles along the blade spanwise direction. The second phase provides optimal material distribution for the composite blade. Loadings on the blade are simulated using wind field and wind turbine dynamics codes. The maximum loads on the turbine blade are then extracted and applied to a parameterized finite element model. A design example of a 3 MW wind turbine blade considering one critical load case with a mean wind speed of 25 m/s is demonstrated. The optimization result shows that although the initial blade model is an infeasible design, the optimization process eventually converges to a feasible solution with an optimized mass of 8750.2 kg.

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Geometric nonlinear dynamic response of wind turbines with different power performance

E3S Web of Conferences ◽

10.1051/e3sconf/202127101005 ◽

2021 ◽

Vol 271 ◽

pp. 01005

Author(s):

Xiaohang Qian ◽

Zhiteng Gao ◽

Zhiyong Zhang ◽

Tongguang Wang

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Nonlinear Dynamic ◽

Geometric Nonlinearity ◽

Large Scale ◽

Turbine Blades ◽

Dynamic Responses ◽

Analysis Model ◽

Wind Turbine Blades ◽

Geometrically Exact Beam

As the size of wind turbine blades increases, the influence of geometric nonlinearity on aerodynamic, structural and design of blades becomes more and more serious. In this work, the efficient aero-elastic calculation of large flexible blades is studied. In order to solve the problem of efficient aeroelastic caculation of large flexible blades, this work applied the geometrically exact beam theory based on Legendre spectral finite element and coupled with the blade element momentum theory to establish the aero-elastic analysis model of large flexible blades. This model can efficiently calculate the deformation and load on the blade under aerodynamic loading and fully consider the influence of geometric nonlinearity caused by deformation on aeroelastic ability. Taking NREL 5MW and IEA 15MW wind turbines as examples, the linear and nonlinear dynamic responses of these two wind turbine blades are calculated. The result shows that the neglect of nonlinear effect will bring error. From 5MW wind turbine to 15MW wind turbine, the numerical error increased by 27.88%. The influence of geometric nonlinearity of blades on dynamic responses is analysed, which is of great significance to improve the design level of large-scale wind turbines.

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Scaling Three-Dimensional Low-Pressure Turbine Blades for Low-Speed Testing

Journal of Turbomachinery ◽

10.1115/1.4033259 ◽

2016 ◽

Vol 138 (11) ◽

Cited By ~ 2

Author(s):

Matteo Giovannini ◽

Michele Marconcini ◽

Filippo Rubechini ◽

Andrea Arnone ◽

Francesco Bertini

Keyword(s):

Turbine Blade ◽

High Speed ◽

Large Scale ◽

General Procedure ◽

Turbine Blades ◽

Three Dimensional ◽

Low Pressure ◽

Low Speed ◽

Scaling Procedure ◽

Inlet Conditions

The present activity was carried out in the framework of the Clean Sky European Research Project ITURB (optimal high-lift turbine blade aeromechanical design), aimed at designing and validating a turbine blade for a geared open-rotor engine. A cold-flow, large-scale, low-speed (LS) rig was built in order to investigate and validate new design criteria, providing reliable and detailed results while containing costs. This paper presents the design of an LS stage and describes a general procedure that allows to scale three-dimensional (3D) blades for LS testing. The design of the stator row was aimed at matching the test-rig inlet conditions and at providing the proper inlet flow field to the blade row. The rotor row was redesigned in order to match the performance of the high-speed (HS) configuration, compensating for both the compressibility effects and different turbine flow paths. The proposed scaling procedure is based on the matching of the 3D blade loading distribution between the real engine environment and the LS facility one, which leads to a comparable behavior of the boundary layer and hence to comparable profile losses. To this end, the datum blade is parameterized, and a neural-network-based methodology is exploited to guide an optimization process based on 3D Reynolds-averaged Navier–Stokes (RANS) computations. The LS stage performance was investigated over a range of Reynolds numbers characteristic of modern low-pressure turbines (LPTs) by using a multi-equation, transition-sensitive, turbulence model. Some comparisons with experimental data available within the project finally proved the effectiveness of the proposed scaling procedure.

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Optimal Design of Wind Boosters for Low Speed Vertical Axis Wind Turbines

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.798.195 ◽

2015 ◽

Vol 798 ◽

pp. 195-199 ◽

Cited By ~ 3

Author(s):

Natapol Korprasertsak ◽

Thananchai Leephakpreeda

Keyword(s):

Wind Speed ◽

Optimal Design ◽

Wind Turbines ◽

Optimization Technique ◽

Vertical Axis ◽

Mechanical Power ◽

Original Design ◽

Guide Vanes ◽

Low Speed ◽

Vertical Axis Wind Turbines

Although Vertical Axis Wind Turbines (VAWTs) are designed for performing mechanical works acceptably at medium wind speed, Standalone VAWTs are still unable to generate mechanical power satisfactorily for best practice at low speed wind. This study presents optimal design of wind booster, by utilizing Computational Fluid Dynamics (CFD). A wind booster is proposed to be implemented with a VAWT in order to not only harvest energy with low availability at low wind speed but also enhance performance of a VAWT at higher wind speed. In CFD-based experiments, guiding and throttling effects of the wind booster are able to increase mechanical power of a VAWT. Optimal alternatives of number and leading angle of guide vanes are determined by maximizing the coefficient of power from the alternating direction method as an optimization technique. The VAWT coupled with the optimal wind booster, which consists of 8 guide vanes and leading angle of 55o, is cable of producing mechanical power higher up to the coefficient of power of 4.8 % than the original design.

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Optimal Design of Novel Blade Profile for Savonius Wind Turbines

Energies ◽

10.3390/en14123484 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3484

Author(s):

Tai-Lin Chang ◽

Shun-Feng Tsai ◽

Chun-Lung Chen

Keyword(s):

Wind Energy ◽

Drag Force ◽

Wind Turbines ◽

Rural Areas ◽

Large Scale ◽

Design Method ◽

Angular Position ◽

Vertical Axis ◽

Blade Profile ◽

Main Concept

Since the affirming of global warming, most wind energy projects have focused on the large-scale Horizontal Axis Wind Turbines (HAWTs). In recent years, the fast-growing wind energy sector and the demand for smarter grids have led to the use of Vertical Axis Wind Turbines (VAWTs) for decentralized energy generation systems, both in urban and remote rural areas. The goals of this study are to improve the Savonius-type VAWT’s efficiency and oscillation. The main concept is to redesign a Novel Blade profile using the Taguchi Robust Design Method and the ANSYS-Fluent simulation package. The convex contour of the blade faces against the wind, creating sufficient lift force and minimizing drag force; the concave contour faces up to the wind, improving or maintaining the drag force. The result is that the Novel Blade improves blade performance by 65% over the Savonius type at the best angular position. In addition, it decreases the oscillation and noise accordingly. This study achieved its two goals.

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Novel Application and Validation of a Method to Assess Visual Impacts of Rotating Wind Turbine Blades Within Woodland Areas

PFG – Journal of Photogrammetry Remote Sensing and Geoinformation Science ◽

10.1007/s41064-021-00141-4 ◽

2021 ◽

Vol 89 (1) ◽

pp. 1-14

Author(s):

U. Nopp-Mayr ◽

F. Kunz ◽

F. Suppan ◽

E. Schöll ◽

J. Coppes

Keyword(s):

Environmental Impact ◽

Wind Turbine ◽

Wind Turbines ◽

Power Plants ◽

Laser Scanning ◽

Forest Canopy ◽

Turbine Blades ◽

Wind Turbine Blades ◽

Environmental Impact Assessments ◽

Independent Field

AbstractIncreasing numbers of wind power plants (WPP) are constructed across the globe to reduce the anthropogenic contribution to global warming. There are, however, concerns on the effects of WPP on human health as well as related effects on wildlife. To address potential effects of WPP in environmental impact assessments, existing models accounting for shadow flickering and noise are widely applied. However, a standardized, yet simple and widely applicable proxy for the visibility of rotating wind turbines in woodland areas was largely lacking up to date. We combined land cover information of forest canopy extracted from orthophotos and airborne laser scanning (LiDAR) data to represent the visibility of rotating wind turbines in five woodland study sites with a high spatial resolution. Performing an in-situ validation in five study areas across Europe which resulted in a unique sample of 1738 independent field observations, we show that our approach adequately predicts from where rotating wind turbine blades are visible within woodlands or not. We thus provide strong evidence, that our approach yields a valuable proxy of the visibility of moving rotor blades with high resolution which in turn can be applied in environmental impact assessments of WPP within woodlands worldwide.

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