The effects of shape and size on duct-augmented horizontal axis turbine performance

2020 ◽  
pp. 0309524X2093883
Author(s):  
Aditya Rachman ◽  
Andrew Johnstone ◽  
Buyung Kosasih
Keyword(s):  
System Performance ◽  
Horizontal Axis ◽  
Geometric Features ◽  
Analytic Model ◽  
Element Analysis ◽  
Turbine Performance ◽  
Expansion Angle ◽  
Shape And Size ◽  
Horizontal Axis Turbine ◽  
Blade Element

This article seeks to contribute to knowledge on duct-augmented turbines by investigating the influence of the key geometric parameters of the duct on the turbine performance: (i) duct expansion angle and length, (ii) position of the duct relative to the rotor and (iii) added geometric features to the duct. A new analytic model is proposed for the duct-augmented turbine and used for the investigation. The proposed analytic model used in this study was developed with existing momentum and blade element analysis methodologies serving as its basis. Using the proposed analytic model, the duct length is found to be more influential on the duct turbine system performance than the duct expansion angle. In addition, the performance can be enhanced by addition of a flange to the duct trailing edge. The study also highlights that the optimum rotor location within a duct is slightly behind the minimum duct area.

scholarly journals Horizontal Axis Wind Turbine Performance Analysis

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
N. Asmuin ◽  
◽  
Basuno B. ◽  
M.F. Yaakub ◽  
N.A. Nor Salim ◽  
...  
Keyword(s):  
Wind Turbine ◽  
Horizontal Axis ◽  
Power Coefficient ◽  
Horizontal Axis Wind Turbine ◽  
Thrust Coefficient ◽  
Blade Element Momentum Theory ◽  
Blade Element Theory ◽  
Momentum Theory ◽  
Turbine Performance ◽  
Blade Element

The present work uses the method of Blade Element Momentum Theory as suggested by Hansen. The method applied to three blade models adopted from Rahgozar S. with the airfoil data used the data provided by Wood D. The wind turbine performance described in term of the thrust coefficient C_T, torque coefficient C_Q and the power coefficient C_p . These three coefficient can be deduced from the Momentum theory or from the Blade element Theory(BET). The present work found the performance coefficient derived from the Momentum theory tent to over estimate. It is suggested to used the BET formulation in presenting these three coefficients. In overall the Blade Element Momentum Theory follows the step by step as described by Hansen work well for these three blade models. However a little adjustment on the blade data is needed. To the case of two bladed horizontal axis wind

Wind Tunnel Tests of a Model Small-scale Horizontal-axis Wind Turbine Developed from Blade Element Momentum Theory

2021 ◽  
pp. 1-16
Author(s):  
Ojing Siram ◽  
Niranjan Sahoo ◽  
Ujjwal K. Saha
Keyword(s):  
Wind Tunnel ◽  
Horizontal Axis ◽  
Superior Performance ◽  
Speed Ratio ◽  
Small Scale ◽  
Blade Design ◽  
Horizontal Axis Wind Turbine ◽  
Blade Element Momentum Theory ◽  
Momentum Theory ◽  
Blade Element

Abstract The small-scale horizontal-axis wind turbines (SHAWTs) have emerged as the promising alternative energy resource for the off-grid electrical power generation. These turbines primarily operate at low Reynolds number, low wind speed, and low tip speed ratio conditions. Under such circumstances, the airfoil selection and blade design of a SHAWT becomes a challenging task. The present work puts forward the necessary steps starting from the aerofoil selection to the blade design and analysis by means of blade element momentum theory (BEMT) for the development of four model rotors composed of E216, SG6043, NACA63415, and NACA0012 airfoils. This analysis shows the superior performance of the model rotor with E216 airfoil in comparison to other three models. However, the subsequent wind tunnel study with the E216 model, a marginal drop in its performance due to mechanical losses has been observed.

Finite Element Analysis of Metal Flow of Finishing Groove in Hot Continuous Rolling Bar

2012 ◽  
Vol 510 ◽  
pp. 667-672
Author(s):  
Jia Lin Zhou ◽  
Chen Gang Pan ◽  
Xiao Yong Zhang
Keyword(s):  
Strain Distribution ◽  
Metal Flow ◽  
Dimensional Accuracy ◽  
Stress And Strain ◽  
Fe Model ◽  
Element Analysis ◽  
Iron And Steel ◽  
Expansion Angle ◽  
The Stability ◽  
Stress And Strain Distribution

This article established 3D FE model of dual-radius arc finishing groove and tangent expansion angle finishing groove using ANSYS / LS-DYNA software for Wuhan Iron and Steel plant Ф16 hot continuous bar, and analyzed metal flow pattern, stress and strain distribution of two types finishing grooves. The results show that surface stress and strain distribution of dual-radius arc finishing groove have better uniform than them of tangent expansion angle finishing groove, and dual-radius arc finishing groove ensures the stability of the rolled piece in finishing groove, improve the dimensional accuracy and surface quality of rolled finishing product.

scholarly journals Modeling and simulation of forces applied to the horizontal axis wind turbine rotors by the vortex method coupled with the method of the blade element

2021 ◽  
Vol 12 (1) ◽  
pp. 413
Author(s):  
Ibtissem Barkat ◽  
Abdelouahab Benretem ◽  
Fawaz Massouh ◽  
Issam Meghlaoui ◽  
Ahlem Chebel
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Wind Farms ◽  
Vortex Method ◽  
Operating Conditions ◽  
Horizontal Axis ◽  
Rotor Blades ◽  
Good Representation ◽  
Horizontal Axis Wind Turbine ◽  
Blade Element

This article aims to study the forces applied to the rotors of horizontal axis wind turbines. The aerodynamics of a turbine are controlled by the flow around the rotor, or estimate of air charges on the rotor blades under various operating conditions and their relation to the structural dynamics of the rotor are critical for design. One of the major challenges in wind turbine aerodynamics is to predict the forces on the blade as various methods, including blade element moment theory (BEM), the approach that is naturally adapted to the simulation of the aerodynamics of wind turbines and the dynamic and models (CFD) that describes with fidelity the flow around the rotor. In our article we proposed a modeling method and a simulation of the forces applied to the horizontal axis wind rotors turbines using the application of the blade elements method to model the rotor and the vortex method of free wake modeling in order to develop a rotor model, which can be used to study wind farms. This model is intended to speed up the calculation, guaranteeing a good representation of the aerodynamic loads exerted by the wind.

A Study on Durability Enhancement of Band Brake for Mooring Winch

2011 ◽  
Vol 201-203 ◽  
pp. 314-317
Author(s):  
Dong Seop Han ◽  
Geun Jo Han ◽  
Dong Hwan Choi
Keyword(s):  
Brake System ◽  
Analytic Model ◽  
Uniform Thickness ◽  
Element Analysis ◽  
Brake Shoe ◽  
The Finite Element Analysis ◽  
Brake Lining ◽  
Different Thickness ◽  
Ansys Workbench ◽  
Excessive Stress

The brake system is very important part of the machine working. The mooring winch brake holds the ship on the harbor. But sometimes it appeared the excessive stress and brake lining would be broken. So it is necessary to change the shape of brake system with improve the durability of brake band. In this research, three models, such as a single brake shoe with a uniform thickness, a dual brake shoe with a uniform thickness, and a dual brake shoe with different thickness, are adopted as analytic model. In order to evaluate the strength of band brake according to the shape of brake shoe, the finite element analysis for three models is carried out by using ANSYS Workbench.

scholarly journals Comparison of the Stator Step Skewed Structures for Cogging Force Reduction of Linear Flux Switching Permanent Magnet Machines

Energies ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 2172 ◽  
Author(s):  
Wenjuan Hao ◽  
Yu Wang
Keyword(s):  
Finite Element Analysis ◽  
System Performance ◽  
Thrust Force ◽  
Low Cost ◽  
Good Choice ◽  
Permanent Magnet Machines ◽  
Maximum Difference ◽  
Element Analysis ◽  
Rotary Machines ◽  
Force Reduction

Linear flux switching permanent magnetic (LFSPM) machines, with the armature windings and magnets both on the mover in addition to a robust stator, are a good choice for long stoke applications, however, a large cogging force is also inevitable due to the double salient structure, and will worsen the system performance. Skewing methods are always employed for the rotary machines to reduce the cogging torque, and the rotor step-skewed method is a low-cost approximation of regular skewing. The step skewed method can also be applied to the linear machines, namely, the stator step skewed. In this paper, three stator step skewed structures, which are a three-step skewed stator, a two-step skewed stator and an improved two-step skewed stator, are employed for the cogging force reduction of two types of LFSPM machines. The three structures are analyzed and compared with emphasize on the influence of the skewed displacement on the cogging force and the average thrust force. Based on finite element analysis (FEA), proper skewed displacements are selected according to maximum difference between the reduction ratio of the cogging force and the decrease ratio of the average thrust force, then, the corresponding results are compared, and finally, valuable conclusions are drawn according to the comparison. The comparison presented in this paper will be useful to the cogging force reduction of LFSPM machines in general.

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.

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