To see the other types of publications on this topic, follow the link: VAWT (vertical axis wind turbine).
Journal articles on the topic 'VAWT (vertical axis wind turbine)'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'VAWT (vertical axis wind turbine).'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Khudri Johari, Muhd, Muhammad Azim A Jalil, and Mohammad Faizal Mohd Shariff. "Comparison of horizontal axis wind turbine (HAWT) and vertical axis wind turbine (VAWT)." International Journal of Engineering & Technology 7, no. 4.13 (October 9, 2018): 74. http://dx.doi.org/10.14419/ijet.v7i4.13.21333.
Full textAbstract:
As the demand for green technology is rising rapidly worldwide, it is important that Malaysian researchers take advantage of Malaysia’s windy climates and areas to initiate more power generation projects using wind. The main objectives of this study are to build a functional wind turbine and to compare the performance of two types of design for wind turbine under different speeds and behaviours of the wind. A three-blade horizontal axis wind turbine (HAWT) and a Darrieus-type vertical axis wind turbine (VAWT) have been designed with CATIA software and constructed using a 3D-printing method. Both wind turbines have undergone series of tests before the voltage and current output from the wind turbines are collected. The result of the test is used to compare the performance of both wind turbines that will imply which design has the best efficiency and performance for Malaysia’s tropical climate. While HAWT can generate higher voltage (up to 8.99 V at one point), it decreases back to 0 V when the wind angle changes. VAWT, however, can generate lower voltage (1.4 V) but changes in the wind angle does not affect its voltage output at all. The analysis has proven that VAWT is significantly more efficient to be built and utilized for Malaysia’s tropical and windy climates. This is also an initiative project to gauge the possibility of building wind turbines, which could be built on the extensive and windy areas surrounding Malaysian airports.
2
Mohan Kumar, Palanisamy, Krishnamoorthi Sivalingam, Teik-Cheng Lim, Seeram Ramakrishna, and He Wei. "Review on the Evolution of Darrieus Vertical Axis Wind Turbine: Large Wind Turbines." Clean Technologies 1, no. 1 (August 7, 2019): 205–23. http://dx.doi.org/10.3390/cleantechnol1010014.
Full textAbstract:
The objective of the current review is to present the development of a large vertical axis wind turbine (VAWT) since its naissance to its current applications. The turbines are critically reviewed in terms of performance, blade configuration, tower design, and mode of failure. The early VAWTs mostly failed due to metal fatigue since the composites were not developed. Revisiting those configurations could yield insight into the future development of VAWT. The challenges faced by horizontal axis wind turbine (HAWT), especially in the megawatt capacity, renewed interest in large scale VAWT. VAWT provides a solution for some of the immediate challenges faced by HAWT in the offshore environment in terms of reliability, maintenance, and cost. The current rate of research and development on VAWT could lead to potential and economical alternatives for HAWT. The current summary on VAWT is envisioned to be an information hub about the growth of the Darrieus turbine from the kW capacity to megawatt scale.
3
Horiuchi, Kenji, Izumi Ushiyama, and Kazuichi Seki. "Straight Wing Vertical Axis Wind Turbines: A Flow Analysis." Wind Engineering 29, no. 3 (May 2005): 243–52. http://dx.doi.org/10.1260/030952405774354840.
Full textAbstract:
This research examines the flow velocity characters around lift-based straight-wing vertical-axis wind turbines (SW-VAWT) by numerical simulation. The precision of the prediction technique was confirmed. Furthermore, we estimate the flow behaviour during the wind turbine rotation by using this numerical simulation technique, and evaluate the flow around the SW-VAWT. This paper presents an outline of the work and gives the results of the calculations.
4
Guo, Jia, and Liping Lei. "Flow Characteristics of a Straight-Bladed Vertical Axis Wind Turbine with Inclined Pitch Axes." Energies 13, no. 23 (November 28, 2020): 6281. http://dx.doi.org/10.3390/en13236281.
Full textAbstract:
Currently, vertical axis wind turbines (VAWT) are considered as an alternative technology to horizontal axis wind turbines in specific wind conditions, such as offshore farms. However, complex unsteady wake structures of VAWTs exert a significant influence on performance of wind turbines and wind farms. In the present study, instantaneous flow fields around and downstream of an innovative VAWT with inclined pitch axes are simulated by an actuator line model. Unsteady flow characteristics around the wind turbine with variations of azimuthal angles are discussed. Several fluid parameters are then evaluated on horizontal and vertical planes under conditions of various fold angles and incline angles. Results show that the total estimated wind energy in the shadow of the wind turbine with an incline angle of 30° and 150° is 4.6% higher than that with an incline angle of 90°. In this way, appropriate arrangements of wind turbines with various incline angles have the potential to obtain more power output in a wind farm.
5
Mohammed, Gwani, Mamuda Buhari, Umar Muhammed Kangiwa, and John Danyaro. "Design, Fabrication and Performance Evaluation of Hybrid Vertical Axis Wind Turbine." International Journal for Modern Trends in Science and Technology 6, no. 6 (June 28, 2020): 80–86. http://dx.doi.org/10.46501/ijmtst060618.
Full textAbstract:
Vertical axis wind turbines (VAWT) have attracted a lot of attention recently as an efficient tool in harnessing wind energy; however these types of wind turbine are faced with some challenges which affect their overall performance. The Darrieus rotor has difficulty to self-start by itself while the Savonius rotor has low efficiency. The performance of these turbines can be improved by combining the two VAWTs as one system. This paper presents the design of a hybrid VAWTs turbine. The Hybrid VAWTs combines the Darrieus rotor and the Savonius rotor as a single system to produce a high starting torque and enhanced efficiency. The Savonius rotor is placed at the centre of the three vertical blades of the Darrieus H-rotor to form the hybrid VAWTs. The hybrid VAWT was tested at four different wind speed i.e. V = 4.80 m/s, 4.50 m/s, 4.30 m/s and 3.90 m/s respectively. The performance of the hybrid VAWT was compared with the conventional straight bladed VAWT under similar experimental conditions. The obtained results showed that there is substantial improvement in the self-starting ability and coefficient of power (Cp). At V = 4.80 m/s, the Cp values for hybrid VAWT increased by 92% compared to straight bladed H-rotor VAWT. Similar improvement was also observed at wind speed of V = 4.50 m/s, 4.30 m/s, and 3.90 m/s where the Cp values increases by 71%, 10%, and 67% respectively compared to the straight bladed H-rotor.
6
Junaidin, Buyung. "PERANCANGAN PURWARUPA VERTICAL AXIS WIND TUBINE (VAWT) SKALA KECIL." Angkasa: Jurnal Ilmiah Bidang Teknologi 9, no. 2 (December 14, 2017): 29. http://dx.doi.org/10.28989/angkasa.v9i2.177.
Full textAbstract:
Konsumsi energi yang berasal dari bahan bakar fosil yang semakin tinggi dan ketersediannya di alam yang terbatas sehingga jumlahnya makin lama semakin berkurang, memaksa orang untuk mencari alternatif sumber energi lain. Energi angin menjadi salah satu energi alternatif yang penting dan diperhitungkan sejak adanya krisis energi dan isu lingkungan (polusi udara) akibat penggunaan bahan bakar fosil. Energi angin dimanfaatkan dengan cara mengubah gerakan angin menjadi energi listrik dengan turbin angin (wind turbine). Banyak turbin angin dengan skala besar yang telah dibuat atau dikembangkan di berbagai negara karena terbukti sangat efektif untuk menghasilkan energi listrik. Turbin angin skala kecil juga ikut dibuat dan dikembangkan hingga saat ini karena beberapa kelebihannya jika dibandingkan dengan turbin angin skala besar. Kelebihan itu diantaranya tidak terbatasnya daerah atau lokasi pemasangan turbin angin karena ukurannya yang kecil sehingga dapat ditempatkan di daerah seperti perkotaan. Untuk turbin angin skala kecil, jenis vertical axis wind turbine (vawt) sangatlah cocok digunakan di daerah perkotaan karena karakteristik VAWT yang dapat bergerak tanpa tergantung arah angin, hal ini sesuai dengan karakteristik angin perkotaan. Selain itu, VAWT dapat bergerak dan menghasilkan energi listrik pada kondisi kecepatan angin yang rendah. Penelitian ini fokus pada perancangan VAWT skala kecil yang dapat diaplikasikan pada kecepatan angin rendah dan berubah-ubah arah seperti karakteristik angin di perkotaan Indonesia serta analisis aerodinamika menggunakan metode double-multiple stream-tube (DMS).
7
Cao, Yang, Xiao Ning Li, Guo Qing Wu, Xing Hua Chen, and Xiao Yan Tian. "Design and Optimization of Vertical Axis Wind Turbine." Applied Mechanics and Materials 150 (January 2012): 148–53. http://dx.doi.org/10.4028/www.scientific.net/amm.150.148.
Full textAbstract:
Wind power is a clean and renewable energy, and more and more countries in the world attach great importance to it and promote the development of the wind power industry. The current situation of wind turbines at home and abroad, the development, types, and characteristics were analyzed. The structural design of vertical axis wind turbine (VAWT) and aerodynamic theory of rotor blade were briefly introduced, the characteristic parameters in VAWT design were presented in this paper. Using finite element analysis method, the spindle which is the crucial component of VAWT under the extreme wind load was analyzed, and the corresponding results were obtained. Finally the wall thickness and the structure of spindle were improved and optimized to satisfy the engineering requirements of spindle.
8
Brownstein, Ian D., Nathaniel J. Wei, and John O. Dabiri. "Aerodynamically Interacting Vertical-Axis Wind Turbines: Performance Enhancement and Three-Dimensional Flow." Energies 12, no. 14 (July 16, 2019): 2724. http://dx.doi.org/10.3390/en12142724.
Full textAbstract:
This study examined three-dimensional, volumetric mean velocity fields and corresponding performance measurements for an isolated vertical-axis wind turbine (VAWT) and for co- and counter-rotating pairs of VAWTs with varying incident wind direction and turbine spacings. The purpose was to identify turbine configurations and flow mechanisms that can improve the power densities of VAWT arrays in wind farms. All experiments were conducted at a Reynolds number of R e D = 7.3 × 10 4 . In the paired arrays, performance enhancement was observed for both the upstream and downstream turbines. Increases in downstream turbine performance correlate with bluff–body accelerations around the upstream turbine, which increase the incident freestream velocity on the downstream turbine in certain positions. Decreases in downstream turbine performance are determined by its position in the upstream turbine’s wake. Changes in upstream turbine performance are related to variations in the surrounding flow field due to the presence of the downstream rotor. For the most robust array configuration studied, an average 14% increase in array performance over approximately a 50° range of wind direction was observed. Additionally, three-dimensional vortex interactions behind pairs of VAWT were observed that can replenish momentum in the wake by advection rather than turbulent diffusion. These effects and their implications for wind-farm design are discussed.
9
Khammas, Farhan Ahmed, Kadhim Hussein Suffer, Ryspek Usubamatov, and Mohmmad Taufiq Mustaffa. "Overview of Vertical Axis Wind Turbine (VAWT) is one of the Wind Energy Application." Applied Mechanics and Materials 793 (September 2015): 388–92. http://dx.doi.org/10.4028/www.scientific.net/amm.793.388.
Full textAbstract:
This paper reviews the available types of wind turbine which is one of the wind energy applications. The authors intend to give investors a better idea of which turbine is suitable for a particular setting and to provide a new outlook on vertical axis wind turbines. Wind technology has grown substantially since its original use as a method to grind grains and will only continue to grow. Vertical-axis wind turbines are more compact and suitable for residential and commercial areas while horizontal-axis wind turbines are more suitable for wind farms in rural areas or offshore. However, technological advances in vertical axis wind turbines that are able to generate more energy with a smaller footprint are now challenging the traditional use of horizontal wind turbines in wind farms. Vertical axis wind turbines do not need to be oriented to the wind direction and offer direct rotary output to a ground-level load, making them particularly suitable for water pumping, heating, purification and aeration, as well as stand-alone electricity generation. The use of high efficiency Darrieus turbines for such applications is virtually prohibited by their inherent inability to self-start.
10
Wasiati, S. W., F. A. Augusta, V. R. P. Purwanto, P. Wulandari, and A. Syahrirar. "Darrieus type vertical axis wind turbine (VAWT) design." Journal of Physics: Conference Series 1517 (April 2020): 012064. http://dx.doi.org/10.1088/1742-6596/1517/1/012064.
Full text
11
Bian, Zhong Guo, Cheng Xian Fan, and Shu Qin Liu. "The Forceanalysis of the Vertical Axis Wind Turbine Arms." Applied Mechanics and Materials 71-78 (July 2011): 4794–97. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.4794.
Full textAbstract:
The strain on the arms of the H-VAWT is complex. The article makes analysis on the moment of inertia and maximum stress of the H-VAWT arms, and calculation is made on an equilateral triangle and a rhombus which has the same perimeter with the former. The article provides a method for analyzing the designation of H-VAWT.
12
Phan, Quang The, Thị Thu Hà Phan, Ahmed Sherif El-Gizawy, and Thị Hồng Mai Phan. "A Way to Enhance the Efficiency of a Vertical Axis Wind Turbine." Applied Mechanics and Materials 889 (March 2019): 410–17. http://dx.doi.org/10.4028/www.scientific.net/amm.889.410.
Full textAbstract:
Vertical Axis Wind Turbine (VAWT) can perform better than Horizontal Axis Wind Turbine (HAWT) because VAWTs are relatively simple, quiet, and easy to install. It can take wind from any directions, and operate efficiently in urban areas where turbulent wind conditions usually happen. The weakest point for its configuration, however, is its low efficiency so more intensive research is required.Actual VAWT performance can be predicted based on a determination of the forces acting on blades that produce the turbine’s torque. Thus, this paper proposed a new model of force analysis for calculation of VAWT’s performance and a way to enhance the efficiency of VAWT through proper variations of the pitch angles. Additionally, in order to increase the efficiency of the VAWT for a given tip speed ratio, the solidity in term of blade’s number can be adjusted.Results show that right changes in the value of pitch angles and proper selection of the number of blades can considerably increase the efficiency of the turbine and reduce amplitude of turbine’s torque variation. The new model of force analysis can be helpful for aerodynamic analysis of the VAWT turbine for its better design.
13
Khairunnisa, Khairunnisa, Syaiful Rachman, Edi Yohanes, Awan Uji Krismanto, Jazuli Fadil, Soedibyo Soedibyo, Mochamad Ashari, and Mahmoud Abuzalata. "Vertical Axis Wind Turbine Improvement using DC-DC Boost Converter." E3S Web of Conferences 188 (2020): 00017. http://dx.doi.org/10.1051/e3sconf/202018800017.
Full textAbstract:
Vertical axis wind turbine (VAWT) can be operated in any direction of wind speed, but it has low rotation. To improve the performance of VAWT in which low rotation, this paper presents a simple control strategy of VAWT using a DC-DC boost converter to tap constant voltage in a standalone application. The main objective of this research is to maintain a constant output voltage of converter despite variation input voltage affected by variable wind speed. A simple proportional-integral (PI) controller has been used for a DC-DC boost converter and tested in MATLAB-Simulink environment, with the closed-loop system of the converter maintain constant output voltage although the wind speed is kept changing. The PI controller obtains the feedback from the output voltage of the boost converter to produce the correct pulse width modulation (PWM) duty cycle and trigger the metal oxide semiconductor field effect transistor (MOSFET) following the reference voltage of the turbine. This system has suppressed the value of overshoot and increased the efficiency of wind turbines as 34 %.
14
Liu, Liqun, Chunxia Liu, and Xuyang Zheng. "Modeling, Simulation, Hardware Implementation of a Novel Variable Pitch Control for H-Type Vertical Axis Wind Turbine." Journal of Electrical Engineering 66, no. 5 (September 1, 2015): 264–69. http://dx.doi.org/10.2478/jee-2015-0043.
Full textAbstract:
Abstract It is well known that the fixed pitch vertical axis wind turbine (FP-VAWT) has some disadvantages such as the low start-up torque and inefficient output efficiency. In this paper, the variable pitch vertical axis wind turbine (VP-VAWT) is analyzed to improve the output characteristics of FP-VAWT by discussing the force of the six blade H type vertical axis wind turbine (VAWT) under the stationary and rotating conditions using built the H-type VAWT model. First, the force of single blade at variable pitch and fixed pitch is analyzed, respectively. Then, the resultant force of six blades at different pitch is gained. Finally, a variable pitch control method based on a six blade H type VP-VAWT is proposed, moreover, the technical analysis and simulation results validate that the variable pitch method can improve the start-up torque of VAWT, and increase the utilization efficiency of wind energy, and reduce the blade oscillation, as comparable with that of FP-VAWT.
15
MERAD, Asmae BOUANANI, and Mama BOUCHAOUR. "MODELING AND SIMULATION OF THE VERTICAL AXIS WIND TURBINE BY QBLADE SOFTWARE." Algerian Journal of Renewable Energy and Sustainable Development 2, no. 02 (December 15, 2020): 181–88. http://dx.doi.org/10.46657/ajresd.2020.2.2.11.
Full textAbstract:
The use of wind energy has no harmful effects on the environment. This makes it a clean energy that is a real alternative to the problem of nuclear waste management and greenhouse gas emissions. Vertical axis wind turbines have prospective advantages in the field of domestic applications, because they have proven effectual in urban areas where wind flow conditions are intermittent, omnidirectional, unsteady and turbulent. The wind cannot ensure a regular energy supply without optimising the aerodynamics of the blades. This article presents a reminder about wind energy and wind turbines, especially the VAWT type wind turbines and also gives a presentation on the aerodynamic side of VAWT by studying the geometry and aerodynamic characteristics of the blade profiles with the acting forces and also the explanation of the DMS multiple flow tube model. This work also gives the different simulation methods to optimize the behaviour of the blades from the selected NACA profiles; the analysis first goes through the design of the blades by the design and simulation software Qblade which is used to calculate also the forces on the blade and the coefficients of lift, drag and fineness. At the end of this article we have the DMS simulation of the VAWT turbines, by determining the power coefficient and the power collected by the turbine to select the wind turbine adapted to a well characterized site.
16
Lv, Yong Zhe, Dong Xiang Jiang, and Yong Jiang. "Numerical Simulation on Small Scale Straight-Blade and Twisted-Blade Vertical Axis Wind Turbine." Advanced Materials Research 455-456 (January 2012): 334–38. http://dx.doi.org/10.4028/www.scientific.net/amr.455-456.334.
Full textAbstract:
This paper presents an analysis on the performance of vertical axis wind turbine of two types, namely straight-blade vertical axis wind turbine (SB-VAWT) and twisted-blade vertical axis wind turbine (TB-VAWT). An attempt of this simulation is to identify which type performs better in the same wind conditions and swept area. Three-dimensional computational fluid dynamics (CFD) was adopted in this analysis, after solid models of them were generated. Preliminary results of torque, power and aerodynamics in the fluid field were obtained for discussion. Finally, there provided some guidance for future wind tunnel tests.
17
Yao, Qi, Ying Xue Yao, Liang Zhou, and Zhi Peng Tang. "The Development of the Efficiency Enhancement Mechanism of the Vertical Axis Wind Turbine." Key Engineering Materials 499 (January 2012): 336–41. http://dx.doi.org/10.4028/www.scientific.net/kem.499.336.
Full textAbstract:
The energy issue has been the focus of world’s attention. Wind plays a crucial role in the development and application of new energy as a renewable and clean energy. Wind turbine is the core component of the wind power system. It usually can be divided into horizontal axis wind turbine (HAWT) and vertical axis wind turbine (VAWT) by the relative position of the spindle and the ground. This paper analyzes the advantages and disadvantages of VAWT and summarizes the improvement of the VAWT from the energy congregating technology and self-starting technology which can provide technical support for the research of VAWT in the future.
18
Hsiao, Yung Chia. "Control and System Integration of a Small Vertical-Axis Wind Rotor Coupled a Generator Having Two Windings." Applied Mechanics and Materials 284-287 (January 2013): 1072–76. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.1072.
Full textAbstract:
Increase in the efficiency of a small vertical-axis wind turbine (VAWT) elevates its potential that compares with a horizontal-axis wind turbine (HAWT). The efficiency does not only depend on the power coefficient of the wind rotor but also on the efficiency of the generator. A permanent magnet synchronous generator having two windings keeps high efficiency in both of low rotor speed regime and high rotor speed regime. To maximize the electricity output of the VAWT, this study directly coupled a generator having 1kW winding and 3kW winding with a straight wing vertical-axis wind rotor as a 4kW VAWT. Meanwhile, system integration and control systems of the wind power system were developed to make sure the operation and the safety of the VAWT. The average efficiency of the wind power system is 0.32 through field tests. The results demonstrated that the small VAWT has the same potential in comparison with two small HAWTs via using the electrical generator having two windings.
19
Feng, Fang, Chunming Qu, Shouyang Zhao, Yuedi Bai, Wenfeng Guo, and Yan Li. "Static Mechanical Properties and Modal Analysis of a Kind of Lift-Drag Combined-Type Vertical Axis Wind Turbine." International Journal of Rotating Machinery 2018 (August 7, 2018): 1–13. http://dx.doi.org/10.1155/2018/1840914.
Full textAbstract:
In order to explore a set of methods to analyze the structure of Lift-Drag Combined-Type Vertical Axis Wind Turbine (LD-VAWT), a small LD-VAWT was designed according to the corresponding Standards and General Design Requirements for small vertical axis wind turbines. The finite element method was used to calculate and analyze the static mechanical properties and modalities of main parts of a kind of small-scale LD-VAWT. The contours of corresponding stress and displacement were obtained, and first six-order mode vibration profiles of main parts were also obtained. The results show that the main structure parts of LD-VAWT meet the design requirements in the working condition of the rated speed. Furthermore, the resonances of all main parts did not occur during operation in the simulations. The prototype LD-VAWT was made based on the analysis and simulation results in this study and operated steadily. The methods used in this study can be used as a reference for the static mechanical properties and modal analysis of vertical axis wind turbine.
20
Shoukat, Ahmad Adnan, Adnan Aslam Noon, Muhammad Anwar, Hafiz Waqar Ahmed, Talha Irfan Khan, Hasan Koten, Muftooh Ur Rehman Siddiqi, and Aamer Sharif. "Blades Optimization for Maximum Power Output of Vertical Axis Wind Turbine." International Journal of Renewable Energy Development 10, no. 3 (March 12, 2021): 585–95. http://dx.doi.org/10.14710/ijred.2021.35530.
Full textAbstract:
Wind power is a significant and urging sustainable power source asset to petroleum derivatives. Wind machines, for example, H-Darrieus vertical pivot wind turbines (VAWTs) have increased much notoriety in research network throughout the most recent couple of decades because of their applications at destinations having moderately low wind speed. Be that as it may, it is noticed that such wind turbines have low effectiveness. The point of this examination is to plan rotor cutting edges which could create most extreme power yield and execution. Different plan factors, for instance, harmony length, pitch edge, rotor distance across, cutting edge length and pitch point are explored to upgrade the presentation of VAWT. Rotor cutting edges are manufactured using the NACA-0030 structure and tried in wind burrow office and contrast its outcomes and DSM 523 profile. Numerical simulations are performed to get best geometry and stream conduct for achieving greatest power. It is seen that for higher tip-speed-proportion (TSR), shorter harmony length and bigger distance across the rotor (i.e., lower robustness) yields higher effectiveness in NACA 0030. Nevertheless, for lower TSR, the more drawn out agreement length and slighter distance across rotor (i.e., higher strength) gives better implementation. The pitch point is - 2° for TSR = 3 and - 3° for TSR = 2.5. The most extreme power yield of the wind turbine is acquired for the sharp edge profile NACA 0030. Besides, instantaneous control coefficient, power coefficient (CP) is the greatest reason for azimuthal edge of 245° and least esteem for 180°.
21
Roy, Lalit, Kellis Kincaid, Roohany Mahmud, and David W. MacPhee. "Double-Multiple Streamtube Analysis of a Flexible Vertical Axis Wind Turbine." Fluids 6, no. 3 (March 13, 2021): 118. http://dx.doi.org/10.3390/fluids6030118.
Full textAbstract:
Vertical-axis wind turbines (VAWTs) have drawn increased attention for off-grid and off-shore power generation due to inherent advantages over the more popular horizontal-axis wind turbines (HAWTs). Among these advantages are generator locale, omni-directionality and simplistic design. However, one major disadvantage is lower efficiency, which can be alleviated through blade pitching. Since each blade must transit both up- and down-stream each revolution, VAWT blade pitching techniques are not yet commonplace due to increased complexity and cost. Utilizing passively-morphing flexible blades can offer similar results as active pitching, requiring no sensors or actuators, and has shown promise in increasing VAWT performance in select cases. In this study, wind tunnel tests have been conducted with flexible and rigid-bladed NACA 0012 airfoils, in order to provide necessary input data for a Double-Multiple Stream-Tube (DMST) model. The results from this study indicate that a passively-morphing VAWT can achieve a maximum power coefficient (Cp) far exceeding that for a rigid-bladed VAWT CP (18.9% vs. 10%) with reduced normal force fluctuations as much as 6.9%. Operational range of tip-speed ratio also is observed to increase by a maximum of 40.3%.
22
Zou, Li, Kun Wang, Yichen Jiang, Aimin Wang, and Tiezhi Sun. "Wind Tunnel Test on the Effect of Solidity on Near Wake Instability of Vertical-Axis Wind Turbine." Journal of Marine Science and Engineering 8, no. 5 (May 22, 2020): 365. http://dx.doi.org/10.3390/jmse8050365.
Full textAbstract:
Owing to the rapid development of the offshore wind power technology and increasing capacity of wind turbines, vertical-axis wind turbines (VAWTs) have experienced a great development. Nevertheless, the VAWT wake effect, which affects the power generation efficiency and rotor fatigue life, has not been thoroughly understood. In this study, the mid-span wake measurements on a VAWT in six different configurations were conducted. This study aimed to investigate the effect of solidity on near wake instability of vertical-axis wind turbine. By using the wavelet analysis method to analyse the measured velocity (or pressure) time series signals on a multi-scale and with multi-resolution, the dynamic characteristics of the coherent vortex structures in the wake evolution process were determined. The results show that with increasing solidity, the VAWT wake develops into a bluff body wake mode. In addition, a characteristic frequency that is lower than the low-frequency large-scale vortex shedding frequency occur. The wavelet transform was used to decompose and reconstruct the measured data, and the relationship between the low-frequency large-scale vortex shedding and lower frequency pulsation was established. The results provide important data for numerical modelling and new insights into the physical mechanism of the VAWT wake evolution into a bluff body wake.
23
Chougule, P. D., S. R. K. Nielsen, and Biswajit Basu. "Active Blade Pitch Control for Straight Bladed Darrieus Vertical Axis Wind Turbine of New Design." Key Engineering Materials 569-570 (July 2013): 668–75. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.668.
Full textAbstract:
As Development of smallvertical axis wind turbines (VAWT) for urban use is becoming an interestingtopic both within industry and academia. However, there are few new designs ofvertical axis turbines which are customized for building integration. These aregetting importance because they operate at low rotational speed producing veryless noise during operation, although these are less efficient than HorizontalAxis Wind Turbines (HAWT). The efficiency of a VAWT has been significantlyimproved by H-Darrieus VAWT design based on double airfoil technology asdemonstrated by the authors in a previous publication. Further, it is well knowthat the variation of the blade pitch angle during the rotation improves thepower efficiency. A blade pitch variation is implemented by active blade pitchcontrol, which operates as per wind speed and position of the blade withrespect to the rotor. A double multiple stream tube method is used to determinethe performance of the H-Darrieus VAWT. The power coefficient is compared withthat of a fixed pitch and a variable pitch double airfoil blade VAWT. It isdemonstrated that an improvement in power coefficient by 20% is achieved andthe turbine could start at low wind speed
24
Yohana, Eflita, MSK Tony Suryo U, Binawan Luhung, Mohamad Julian Reza, and M. Badruz Zaman. "Experimental Study of Wind Booster Addition for Savonius Vertical Wind Turbine of Two Blades Variations Using Low Wind Speed." E3S Web of Conferences 125 (2019): 14003. http://dx.doi.org/10.1051/e3sconf/201912514003.
Full textAbstract:
The Wind turbine is a tool used in Wind Energy Conversion System (WECS). The wind turbine produces electricity by converting wind energy into kinetic energy and spinning to produce electricity. Vertical Axis Wind Turbine (VAWT) is designed to produce electricity from winds at low speeds. Vertical wind turbines have 2 types, they are wind turbine Savonius and Darrieus. This research is to know the effect of addition wind booster to Savonius vertical wind turbine with the variation 2 blades and 3 blades. Calculation the power generated by wind turbine using energy analysis method using the concept of the first law of thermodynamics. The result obtained is the highest value of blade power in Savonius wind turbine without wind booster (16.5 ± 1.9) W at wind speed 7 m/s with a tip speed ratio of 1.00 ± 0.01. While wind turbine Savonius with wind booster has the highest power (26.3 ± 1.6) W when the wind speed of 7 m/s with a tip speed ratio of 1.26 ± 0.01. The average value of vertical wind turbine power increases Savonius after wind booster use of 56%.
25
Guo, Jia, Timing Qu, and Liping Lei. "Effect of Pitch Parameters on Aerodynamic Forces of a Straight-Bladed Vertical Axis Wind Turbine with Inclined Pitch Axes." Applied Sciences 11, no. 3 (January 24, 2021): 1033. http://dx.doi.org/10.3390/app11031033.
Full textAbstract:
Pitch regulation plays a significant role in improving power performance and achieving output control in wind turbines. The present study focuses on a novel, pitch-regulated vertical axis wind turbine (VAWT) with inclined pitch axes. The effect of two pitch parameters (the fold angle and the incline angle) on the instantaneous aerodynamic forces and overall performance of a straight-bladed VAWT under a tip-speed ratio of 4 is investigated using an actuator line model, achieved in ANSYS Fluent software and validated by previous experimental results. The results demonstrate that the fold angle has an apparent influence on the angles of attack and forces of the blades, as well as the power output of the wind turbine. It is helpful to further study the dynamic pitch regulation and adaptable passive pitch regulation of VAWTs. Incline angles away from 90° lead to the asymmetric distribution of aerodynamic forces along the blade span, which results in an expected reduction of loads on the main shaft and the tower of VAWTs.
26
Borg, M., and M. Collu. "A comparison between the dynamics of horizontal and vertical axis offshore floating wind turbines." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2035 (February 28, 2015): 20140076. http://dx.doi.org/10.1098/rsta.2014.0076.
Full textAbstract:
The need to further exploit offshore wind resources in deeper waters has led to a re-emerging interest in vertical axis wind turbines (VAWTs) for floating foundation applications. However, there has been little effort to systematically compare VAWTs to the more conventional horizontal axis wind turbine (HAWT). This article initiates this comparison based on prime principles, focusing on the turbine aerodynamic forces and their impact on the floating wind turbine static and dynamic responses. VAWTs generate substantially different aerodynamic forces on the support structure, in particular, a potentially lower inclining moment and a substantially higher torque than HAWTs. Considering the static stability requirements, the advantages of a lower inclining moment, a lower wind turbine mass and a lower centre of gravity are illustrated, all of which are exploitable to have a less costly support structure. Floating VAWTs experience increased motion in the frequency range surrounding the turbine [number of blades]×[rotational speed] frequency. For very large VAWTs with slower rotational speeds, this frequency range may significantly overlap with the range of wave excitation forces. Quantitative considerations are undertaken comparing the reference NREL 5 MW HAWT with the NOVA 5 MW VAWT.
27
Hsieh, W. C., J. M. Miao, C. C. Lai, and C. S. Tai. "Experimental Study on Performance of Vertical Axis Wind Turbine with NACA 4-Digital Series of Blades." Advanced Materials Research 488-489 (March 2012): 1055–61. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.1055.
Full textAbstract:
The experimental studies of output power performances of a vertical-axis-wind-turbine (VAWT) had been conducted in suction-type low speed wind tunnel with various free stream velocity. Torque and rotation speed of blades were measured by using torque meter and optical detector to analyze the effect of blade-section shape on the performance of wind turbine. The test model of experiments in the research was H-rotor VAWT. Three shapes of the NACA 4-digital series blade-section, NACA0022, NACA6404, and NACA6422 were taken in this work. Effects of thickness and camber of blade-section, blade numbers, and blade setting angles on the performance of VAWT have been analyzed in detail. The results show that NACA6422 blade-section has rotation speed of 42% higher than that of NACA0022 when the free stream velocity is below 12 m/s and the blade numbers are 4-blade type. Wind turbines with NACA6422 blades also showed that about 10% higher output power than that of NACA0022 blades among the tested range of free stream velocity. Results indicated that wind turbine with blades of anti-symmetric and thick blade-section was generally more suitable for applying to VAWT. All results of this study can be used the optimization design of VAWT blades in further.
28
Vu, Anh Ngoc, and Tung Nguyen Minh Huynh. "An automated analysis process for vertical axis wind turbine." Science and Technology Development Journal 18, no. 4 (December 30, 2015): 145–52. http://dx.doi.org/10.32508/stdj.v18i4.1000.
Full textAbstract:
This paper presents an automated process for analyzing the performance of vertical axis wind turbine (VAWT). The details of this process will be demonstrated, which include the airfoil geometry representation using CST method, a hybrid meshing process combining structured grids and unstructured grids, CFD calculation process and processing data results to calculate the power coefficient of VAWT. These processes are designed as separate modules. CFD methods used in this research is RANS 2D using Realizable k turbulence model. Meshing process will be done on the GAMBIT software, the CFD calculations are done on commercial ANSYS FLUENT software and these processes are controlled by mathematical software MATLAB. The formulas used to calculate the power coefficient will be also introduced in this paper.
29
Ramlee, Muhamad Fadhli, Ahmad Fazlizan, and Sohif Mat. "Performance Evaluation of H-Type Darrieus Vertical Axis Wind Turbine with Different Turbine Solidity." Journal of Computational and Theoretical Nanoscience 17, no. 2 (February 1, 2020): 833–39. http://dx.doi.org/10.1166/jctn.2020.8726.
Full textAbstract:
Among renewable energy resources, wind energy is one of the best alternative for power generation. Recently, vertical axis wind turbine (VAWT) received renewed interest as small-scale wind energy converter due to its suitability for urban application, where the wind condition is known to be unsteady and turbulence. Amongst various type of VAWTs, H-type Darrieus rotor has become more popular, thanks to its simple construction features, resulting to low manufacturing and installation cost. The aim of this paper is to evaluate numerically the power performance of straight-bladed Darrieus VAWT with different turbine solidity using computational fluid dynamic (CFD) technology. A series of two-dimensional CFD simulations of a three-bladed H-type Darrieus rotor were performed with 3 different solidities, σ (0.3, 0.5 and 0.7) to evaluate their power performance. Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations were used to calculate the instantaneous moment coefficient, Cm and power coefficient, Cp over a range of tip speed ratio, λ (0.5–4.5) with a free stream velocity of 8.0 m/s. The simulation results show that high solidity turbine performed well at low values of λ while turbine with low solidity has a wider operating range of λ and performed better at λ > 3.0 due to less blade-wake interactions between upstream and downstream halves of the turbine and lower blockage effect. The findings lend substantially to our understanding of physics flow around blades and turbine in order to optimize the power performance of small scale straight-bladed Darrieus VAWT operating in unsteady and turbulence wind condition.
30
Song, Lei, Hong-Zhao Liu, and Zong-Xiao Yang. "Orthogonal Analysis Based Performance Optimization for Vertical Axis Wind Turbine." Mathematical Problems in Engineering 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/6241360.
Full textAbstract:
Geometrical shape of a vertical axis wind turbine (VAWT) is composed of multiple structural parameters. Since there are interactions among the structural parameters, traditional research approaches, which usually focus on one parameter at a time, cannot obtain performance of the wind turbine accurately. In order to exploit overall effect of a novel VAWT, we firstly use a single parameter optimization method to obtain optimal values of the structural parameters, respectively, by Computational Fluid Dynamics (CFD) method; based on the results, we then use an orthogonal analysis method to investigate the influence of interactions of the structural parameters on performance of the wind turbine and to obtain optimization combination of the structural parameters considering the interactions. Results of analysis of variance indicate that interactions among the structural parameters have influence on performance of the wind turbine, and optimization results based on orthogonal analysis have higher wind energy utilization than that of traditional research approaches.
31
MacPhee, David, and Asfaw Beyene. "Recent Advances in Rotor Design of Vertical Axis Wind Turbines." Wind Engineering 36, no. 6 (December 2012): 647–65. http://dx.doi.org/10.1260/0309-524x.36.6.647.
Full textAbstract:
The following work represents the most recent advances in design and testing of vertical axis wind turbines (VAWT) rotors. VAWTs have received much attention as of late due to proposed advantages in small scale and off grid wind power generation. Thus, many recent works have surfaced involving analysis, design and optimization of VAWT rotors in order to more efficiently convert wind energy to electricity or other readily usable means. This paper is a collection of most of the recent literature works involving VAWT rotor design and testing, the majority of which published after 2005. We discuss research in the designing of various lift based rotors as well as some drag based rotors, hybrids, and various others. The recent work in this area suggests VAWT capacity could dramatically increase in the near future, and play a vital role in obtaining cleaner, more sustainable energy when global energy demand is increasing at an unprecedented rate. HIGHLIGHTS A review of various works involving rotor design and testing of both lift and drag Vertical Axis Wind Turbines (VAWTs) is presented; Benefits of vertical axis wind turbines in small scale and off grid wind power generation is summarized; Much of the recent work, published after 2005, has been directed towards analyzing, designing, and optimizing rotor shapes. The body of this recent work suggests that research on VAWT rotor design continues to flourish and could make VAWTs a viable competitor to more traditional Horizontal Axis Wind Turbines (HAWTs) worldwide.
32
Sun, Ke, Kang Ping Liao, Jian Hua Zhang, and Xiao Rong Ye. "Study on the Affected Factors of Aerodynamic Performance of Vertical Axis Wind Turbine." Advanced Materials Research 512-515 (May 2012): 652–56. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.652.
Full textAbstract:
The study of aerodynamic performance of vertical axis wind turbine is the basis of the VAWT design. The double disk multiple stream-tube, one of the numerical models for predicting the aerodynamic performance of the wind turbine, was used to calculate the aerodynamic performance of the Sandia DOE-17m VAWT. As shown in the comparison of the calculation results and the field test data, the DDMT model is efficient in predicting the aerodynamic performance. And then, a deep analysis of the inherent mechanisms that how the geometric parameters of wind turbine rotor like height to diameter ratio, solidity, chord and the number of blades affect the aerodynamic performance of turbine was made in the present work. The results will be the theoretical basis for the optimization of the design in aerodynamic performance of VAWT in the future work.
33
Zhang, Lidong, Kaiqi Zhu, Junwei Zhong, Ling Zhang, Tieliu Jiang, Shaohua Li, and Zhongbin Zhang. "Numerical Investigations of the Effects of the Rotating Shaft and Optimization of Urban Vertical Axis Wind Turbines." Energies 11, no. 7 (July 18, 2018): 1870. http://dx.doi.org/10.3390/en11071870.
Full textAbstract:
The central shaft is an important and indispensable part of a small scale urban vertical axis wind turbines (VAWTs). Normally, it is often operated at the same angular velocity as the wind turbine. The shedding vortices released by the rotating shaft have a negative effect on the blades passing the wake of the wind shaft. The objective of this study is to explore the influence of the wake of rotating shaft on the performance of the VAWT under different operational and physical parameters. The results show that when the ratio of the shaft diameter to the wind turbine diameter (α) is 9%, the power loss of the wind turbine in one revolution increases from 0% to 25% relative to that of no-shaft wind turbine (this is a numerical experiment for which the shaft of the VAWT is removed in order to study the interactions between the shaft and blade). When the downstream blades pass through the wake of the shaft, the pressure gradient of the suction side and pressure side is changed, and an adverse effect is also exerted on the lift generation in the blades. In addition, α = 5% is a critical value for the rotating shaft wind turbine (the lift-drag ratio trend of the shaft changes differently). In order to figure out the impacts of four factors; namely, tip speed ratios (TSRs), α, turbulence intensity (TI), and the relative surface roughness value (ks/ds) on the performance of a VAWT system, the Taguchi method is employed in this study. The influence strength order of these factors is featured by TSRs > ks/ds > α > TI. Furthermore, within the range we have analyzed in this study, the optimal power coefficient (Cp) occurred under the condition of TSR = 4, α = 5%, ks/ds = 1 × 10−2, and TI = 8%.
34
NURWICAKSANA, WAHYU AULIA, BUDHY SETIAWAN, IKA NOER SYAMSIANA, and SEPTYANA RISKITASARI. "Kontrol Angle of Attack untuk Optimasi Daya padaVertical Axis Wind Turbine Tipe Darrieus." ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika 8, no. 3 (August 27, 2020): 492. http://dx.doi.org/10.26760/elkomika.v8i3.492.
Full textAbstract:
ABSTRAKVAWT (Vertical Axis Wind Turbine) tipe Darrieus NACA0015 merupakan salah satu model dari turbin angin yang bekerja dengan menggunakan angin sebagai sumber penggerak. Namun dari hasil pengamatan, kecepatan angin yang ada tidak konstan setiap saat. Sehingga dari permasalahan ini perlu suatu kontrol yaitu dengan mengendalikan sudut kerja blade VAWT yang dikenal dengan kontrol angle of attack (AoA). Prinsip kerja kontrol AoA yaitu sudut blade diatur agar VAWT bekerja secara optimum dan dapat meningkatkan efisiensi. Metode kontrol AoA menggunakan PID (Proportional–Integral–Derivative) dengan memberikan nilai trial and error pada Kp, Ki, Kd. VAWT ini menggunakan konstanta TSR (Tip Speed Ratio) yaitu 4. Hasil dari penelitian ini yaitu daya yang dihasilkan VAWT dengan kontrol AoA mendapatkan rata-rata efisiensi sebesar 5.16%, sedangkan VAWT tanpa kontrol mendapatkan efisiensi sebesar 3.49%. Sehingga dapat disimpulkan bahwa dengan kontrol AoA, rata-rata efisiensi dayanya naik sebesar 1.67% dari yang tanpa kontrol.Kata Kunci: Kontrol Angle of Attack (AoA), VAWT, TSR, Efisiensi ABSTRACTVAWT (Vertical Axis Wind Turbine) type Darrieus NACA0015 is one model of a wind turbine that works by using wind as a source of propulsion. Conditions from observations, wind speeds that are not constant every time. So from this problem needs control VAWT by controlling the working angle of the VAWT blade is the angle of attack control (AoA). The principle AoA control is that the blade angle adjusted so that the VAWT works optimally and can improve the efficiency. AoA control method uses PID (Proportional-Integral-Derivative) by providing trial and error values for Kp, Ki, Kd. VAWT uses TSR (Tip Speed Ratio) constant which is 4. The results of this research, VAWT with AoA control get an average efficiency of 5.16%, while without control gets an average efficiency of 3.49%. So it can be concluded that with AoA control, the average power efficiency increases by 1.67% from those without control.Keywords: Angle of Attack (AoA) Control, VAWT, TSR, Efficiency
35
Difuntorum, John Keithley, and Louis Angelo M. Danao. "Improving VAWT performance through parametric studies of rotor design configurations using computational fluid dynamics." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 233, no. 4 (August 21, 2018): 489–509. http://dx.doi.org/10.1177/0957650918790671.
Full textAbstract:
Vertical axis wind turbines present several advantages over the horizontal axis machines that make them suitable to a variety of wind conditions. However, due to the complexity of vertical axis wind turbine (VAWT) aerodynamics, available literature on VAWT performance in steady and turbulent wind conditions is limited. This paper aims to numerically predict the performance of a 5 kW VAWT under steady wind conditions through computational fluid dynamics modeling by varying turbine configuration parameters. Two-dimensional VAWT models using a cambered blade (1.5%) were created with open field boundary extents. Turbine configuration parameters studied include blade mounting position, blade fixing angle, and rotor solidity. Baseline case with peak Cp of 0.31 at tip-speed ratio of 4 has the following parameters: mounting position at 0.5c, zero fixing angle, and three blades (solidity = 0.3). Independent parametric studies were carried out and results show that a blade mounting position of 0.7c from the leading edge produces the best performance with maximum Cp = 0.315 while the worst case is a mounting position of 0.15c with peak Cp = 0.273. Fixing angle study reveals a toe-out setting of −1° producing the best performance with peak Cp of 0.315 and the worst setting at toe-in of 1.5° with peak Cp of 0.287. The solidity study resulted in the best case of four blades (solidity = 0.4) with peak Cp = 0.316 and the worst case of two blades (solidity = 0.2) with peak Cp = 0.283.
36
Korprasertsak, Natapol, and Thananchai Leephakpreeda. "Optimal Design of Wind Boosters for Low Speed Vertical Axis Wind Turbines." Applied Mechanics and Materials 798 (October 2015): 195–99. http://dx.doi.org/10.4028/www.scientific.net/amm.798.195.
Full textAbstract:
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.
37
Hendriana, Dena, Eka Budiarto, Alexander Clements, and Arko Djajadi. "Design comparison of wind turbines for low wind speed." ICONIET PROCEEDING 2, no. 3 (February 13, 2019): 222–29. http://dx.doi.org/10.33555/iconiet.v2i3.36.
Full textAbstract:
Wind energy is one of the potential renewable energy, but the applications have to beadjusted to the available wind characteristic in the area. In Indonesia, the wind speed is inaverage not very high, only around 4 m/s. Therefore the wind turbine design have to be adjustedfor usage in Indonesia. In this research, two wind turbine designs are compared. One design isof the form Horizontal-Axis Wind Turbine (HAWT) and the other is of the form Vertical-AxisWind Turbine (VAWT). Both designs are optimized for wind speed of 4 m/s. The comparisonsare done using computer simulation software OpenFOAM. The result shows VAWT design canproduce similar power with smaller turbine dimension than the HAWT design.
38
Mahmood, Yaseen H., and Mahamed K. Bedewy. "Fabricated of Vertical Axis wind turbine (VAWT) and study the parameter." Tikrit Journal of Pure Science 24, no. 7 (December 22, 2019): 99. http://dx.doi.org/10.25130/j.v24i7.918.
Full textAbstract:
Due to the lack of electric power in areas away from power transmission lines and high prices of conventional fuel due to high pollution. A vertical system is used which depends on wind energy used to rotate a vertical turbine. The system is manufactured from local materials and tested. and study the number of blades with the other characterization of system we found, increasing the torque with increasing the blade of turbine, and increasing the power coefficient with increasing the tip speed ratio and low bitz limit.
http://dx.doi.org/10.25130/tjps.24.2019.135
39
Barnes, Andrew, Daniel Marshall-Cross, and Ben Richard Hughes. "Validation and comparison of turbulence models for predicting wakes of vertical axis wind turbines." Journal of Ocean Engineering and Marine Energy 7, no. 4 (July 23, 2021): 339–62. http://dx.doi.org/10.1007/s40722-021-00204-z.
Full textAbstract:
AbstractVertical axis wind turbine (VAWT) array design requires adequate modelling of the turbine wakes to model the flow throughout the array and, therefore, the power output of turbines in the array. This paper investigates how accurately different turbulence models using 2D computational fluid dynamics (CFD) simulations can estimate near and far wakes of VAWTs to determine an approach towards accurate modelling for array design. Three experiments from the literature are chosen as baselines for validation, with these experiments representing the near to far wake of the turbine. Five URANS turbulence models were chosen due to their common and potential usage for VAWT CFD: models k–ω SST, k–ω SST LRN, k–ω SSTI, transition SST, and k–kl–ω. In addition, the lifting line-free vortex wake (LLFWV) model was tested as an alternative to CFD for the far turbine wake where it was appropriate for use. The results for turbulent kinetic energy and vorticity were compared for the first experiment, whilst streamwise and cross-stream velocity were used for the other two experiments. It was found that none of the turbulence models tested or LLFVW produced adequate estimations within the methodology tested, however, transition SST produced the closest estimations. Further adjustments to the methodology are required to improve accuracy due to their large impact on results including use of 3D CFD, adjustment of surface roughness, and inlet flow characteristics.
40
Wiśniewski, Jan, Krzysztof Rogowski, Konrad Gumowski, and Jacek Szumbarski. "Wind tunnel comparison of four VAWT configurations to test load-limiting concept and CFD validation." Wind Energy Science 6, no. 1 (February 24, 2021): 287–94. http://dx.doi.org/10.5194/wes-6-287-2021.
Full textAbstract:
Abstract. The article describes results of experimental wind tunnel testing of four different straight-bladed vertical axis wind turbine model configurations. The experiment tested a novel concept of vertically dividing and azimuthally shifting a turbine rotor into two parts with a specific uneven height division in order to limit cycle amplitudes and average cycle values of bending moments at the bottom of the turbine shaft to increase product lifetime, especially for industrial-scale turbines. Testing reduction effects of simultaneously including a vertical gap between turbine rotor levels, increasing shaft length but also reducing aerodynamic interaction between rotor levels, has also been performed. Experiment results have shown very significant decreases of bending moment cycle amplitudes and average cycle values, for a wide range of measured wind speeds, for dual-level turbine configurations as compared to a single-level turbine configuration. The vertical spacing between levels equal to a blade's single chord length has proven to be sufficient, on laboratory scale, to limit interaction between turbine levels in order to achieve optimal reductions of tested parameters through an operating cycle shift between two position-locked rotor levels during a turbine's expected lifetime. CFD validation of maintaining the effect on industrial scale has been conducted, confirming the initial conclusions.
41
Deshmukh, Samir, and Sagar Charthal. "Design and Development of Vertical Axis Wind Turbine." IRA-International Journal of Technology & Engineering (ISSN 2455-4480) 7, no. 2 (S) (July 10, 2017): 286. http://dx.doi.org/10.21013/jte.icsesd201728.
Full textAbstract:
Wind energy is the kinetic energy associated with movement of large masses of air. These motions result from uneven heating of atmosphere by sun creating temperature, density, pressure differences. It is an indirect form of solar energy The device used to convert kinetic energy of wind into electrical power is called a wind turbine. Vertical Axis wind power generators, represent a very promising future for wind power generation. In present study an attempt is made to utilize at low velocity wind below 4m/s for useful power generation using magnetic levitation for vertical axis wind turbine (VAWT) termed as Maglev turbine. A single large Maglev turbine can give output more than conventional horizontal axis wind turbine (HAWT). The rotor that is designed to harness enough air to rotate the shaft at low and high wind speeds while keeping the centre of mass closer to the base of yielding stability due to Maglev effect. The efficiency of turbine is increased by replacing the conventional bearings by magnets in repulsion; the magnetic levitation helps the turbine to spin at much faster rate as it eliminates the stresses on the shaft of turbine. The major components are placed at the ground level which ensures the safety of turbine.
42
Jadallah, Abdullateef A., Sahar R. Farag, and Jinan D. Hamdi. "Performance Augmenting of a Vertical Axis Wind Turbine using Adaptable Convergent Ducting System." Al-Khwarizmi Engineering Journal 14, no. 3 (September 6, 2018): 141–48. http://dx.doi.org/10.22153/https://doi.org/10.22153/kej.2018.03.003.
Full textAbstract:
Developments are carried out to enhance the performance of vertical axis wind turbines (VAWT). This paper studies the performance of the ducted wind turbine with convergent duct (DAWT). Basically, the duct technique is utilized to provide the desired wind velocity facing the turbine. Methodology was developed to estimate the decisive performance parameter and to present the effect of the convergent duct with different inlet angles. The ducted wind turbine was analyzed and simulated using MATLAB software and numerically using ANSYS-Fluent 17.2. Result of both approaches were presented and showed good closeness for the two cases of covering angles 12 and 20 respectively. Results also showed that the convergent duct with an inlet angle 12 and 20 improved the coefficient of performance at a specified tip speed ratio by 25.8% and 33.33% respectively in the productivity of wind turbine.
43
Syawitri, Taurista Perdana, Yu-Feng Yao, Jun Yao, and Budi Chandra. "The effect of gurney flap on flow characteristics of vertical axis wind turbine." International Journal of Modern Physics B 34, no. 14n16 (June 1, 2020): 2040107. http://dx.doi.org/10.1142/s0217979220401074.
Full textAbstract:
Recently, the Gurney Flap (GF) has been used to improve the performance of Horizontal Axis Wind Turbine (HAWT) by enhancing its lift coefficient. Compared to HAWT, research on GF application for Vertical Axis Wind Turbine (VAWT) is very limited. Moreover, most works studied a GF geometry attached to the trailing edge of a stationary airfoil, without considering the rotating effect experienced by VAWT. For this reason, a three-straight-bladed VAWT rotating blade with GF is studied by transient RANS simulation together with a stress-blended eddy simulation (SBES) turbulence model to investigate the GF height effect and the flow characteristics near the blade trailing edge. Results have shown that by introducing the blade rotating, an optimum GF height is found to be 3% of the blade chord, slightly higher than 2% chord in a stationary airfoil case. In addition, the presence of GF can delay deep stall of VAWT blades, thus eliminating negative instantaneous moment coefficient and improving the turbine performance.
44
Yuan, Zheng, Qihu Sheng, Ke Sun, Jun Zang, Xuewei Zhang, Fengmei Jing, and Renwei Ji. "The Array Optimization of Vertical Axis Wind Turbine Based on a New Asymmetric Wake Model." Journal of Marine Science and Engineering 9, no. 8 (July 29, 2021): 820. http://dx.doi.org/10.3390/jmse9080820.
Full textAbstract:
With the increasing demand for wind energy, the vertical axis wind turbine (VAWT) is attracting more and more attention. In order to design the VAWT array for better performance, the VAWT wake model needs to reflect the wake characteristics well. Based on the asymmetric wake characteristic, a new VAWT wake model is proposed in this paper, which is a combination of two semi Gaussian functions with different deviations, and can be called the “double semi Gaussian functions wake model”. The model is simple and has only four parameters (mean, amplitude, left deviation and right deviation). Compared with the traditional Gaussian and Top-hat model, this model can better reflect the asymmetric characteristic of the VAWT wake. In particular, it can describe the behavior of wake merging in the case of counter-rotating twin turbines. Based on this wake model, the velocity field of VAWT array can be reproduced accurately. The goal function is mainly based on the performance of a basic array unit, and it can ensure the rapidity of the optimization process. The optimal arrangements under two different criteria are analyzed. Moreover, the truncation ratio is introduced to ensure that the downstream turbine works at the rated condition, and the optimal arrangements under different truncation ratios are analyzed. In this paper, the proposed wake model provides a good choice for the preliminary design of the VAWT array, and some relevant suggestions on the array arrangement have been put forward.
45
Wu, Guo Qing, Xinghua Chen, Yang Cao, and Jing Ling Zhou. "Simulation and Test for Two Airfoils with Wind Guide Vane of VAWT." Advanced Materials Research 148-149 (October 2010): 1199–203. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1199.
Full textAbstract:
Two airfoils of vertical axis wind turbine (VAWT) were designed, and the wind guide vane was added for VAWT. By using Fluent and the environment wind tunnel, some results were simulated and tested for two different types of airfoils and its wind guide vane. The performance data on certain condition was obtained. Research showed that utilization of wind energy with guide vane wind turbine was higher than those without guide vane structure. The performance of airfoil was more excellent than airfoil . Wind guide vane structure is a new structure for wind turbine which will have a wide prospect.
46
Admono, Tri, Yoyon Ahmudiarto, Amma Muliya Romadoni, Iman Abdurahman, Agus Salim, Teguh Tri Lusijarto, and Mochammad Agoes Mulyadi. "Numerical investigation of the effect of triangle strut in vertical axis wind turbine (VAWT)." Journal of Mechatronics, Electrical Power, and Vehicular Technology 11, no. 2 (December 22, 2020): 95. http://dx.doi.org/10.14203/j.mev.2020.v11.95-101.
Full textAbstract:
Strut is used in vertical axis wind turbine (VAWT) to restraint the framework. In this study, struts are analyzed to show the pressure losses in VAWT. ANSYS computational fluid dynamics (CFD) software is used to investigate triangle strut in VAWT. This study aims to show a CFD simulation of struts, which affects the aerodynamic of VAWT. In CFD software, the aerodynamic of VAWT can be analyzed in terms of pressure losses in the struts. The simulation method starts by making a struts model, then meshing and setting up ANSYS's boundary conditions. The last iteration runs in ANSYS until convergence. Our results show the percentage of pressure losses with the variation of the angle of wind 0°, 20°, 40°, and 60° are 0.67 %, 0.52 %, 0.48 %, and 0.52 %. The effect of triangle strut in VAWT did not affect the wind flow to the VAWT blade. The results also indicated that the triangle strut could be applied in the multi-stage of VAWT system.
47
Kadhim, H. S., G. A. Quadir, A. K. Farhan, U. Ryspek, and K. A. Ismail. "Numerical Simulation for the Aerodynamics of Vertical Axis Wind Turbine with Two Different Rotors Having Movable Vanes." Applied Mechanics and Materials 786 (August 2015): 205–9. http://dx.doi.org/10.4028/www.scientific.net/amm.786.205.
Full textAbstract:
Wind energy has seen a rapid growth worldwide. Wind turbines are typical devices that convert the kinetic energy of wind into electricity. Researches in the past have proved that Vertical Axis Wind Turbines (VAWTs) are more suitable for urban areas than Horizontal Axis Wind Turbines (HAWTs). In the present design of the VAWT, the power prodused depends on the drag force generated by the individual blades and interactions between them in a rotating configuration. Numerical simulation for the aerodynamics of VAWT with tow different rotors (Three and Foure blades ) having movable vanes are curred out. The For numerical simulation, commercially available computational fluid dynamic (CFD) softwares GAMBIT and FLUENT are used. In this work the Shear Stress Transport (SST) k-ω turbulence model was used which is better than the other turbulence models available as suggested by some researchers. The predicted results show agreement with those reported in the literature for VAWT having different blades designs.
48
Divakaran, Unnikrishnan, Ajith Ramesh, Akram Mohammad, and Ratna Kishore Velamati. "Effect of Helix Angle on the Performance of Helical Vertical Axis Wind Turbine." Energies 14, no. 2 (January 12, 2021): 393. http://dx.doi.org/10.3390/en14020393.
Full textAbstract:
The energy crisis has forced researchers to look for various non-conventional energy sources. Wind energy is one of the potential sources, and researchers have invested resources in developing different kinds of wind turbines. Vertical axis wind turbines (VAWT) have received less attention than their horizontal-axis counterparts. A helical-bladed VAWT is preferred because it makes perfect sense as an improvement in design, as they have higher azimuth angles of power generation capabilities. This paper studies the effects of the helix angle of blades in the aerodynamic performance of VAWT using 3D numerical simulations. Three different helix angles of 60°, 90°, and 120° of a three-bladed VAWT operating across different tip speed ratios were studied. Turbulence is modelled using a four-equation transition SST k-ω model (shear stress transport). The 60° helical-bladed VAWT was found to be better performing in comparison with all other helical-bladed and straight-bladed VAWT. The ripple effects on the shaft are also analysed using a standard deviation plot of the moment coefficient generated by a single blade over one complete cycle of its rotation. It was observed that the greater the helix angle, the lower the standard deviation. The paper also tries to analyse the percentage of power generated by each quartile of flow and the contribution of each section of the blade. Ansys FLUENT was employed for the entire study. A comparative study between different helical-bladed VAWT and straight-bladed VAWT was carried out along with wake structure analysis and flow contours for a better understanding of the flow field.
49
El-Sayed, A. F. Abdel Azim, C. Hirsch, and R. Derdelinckx. "Dynamics of Vertical Axis Wind Turbines (Darrieus Type)." International Journal of Rotating Machinery 2, no. 1 (1995): 33–41. http://dx.doi.org/10.1155/s1023621x95000182.
Full textAbstract:
A computing package that combines finite element methods for evaluating the resonance frequencies and modes of turbine subcomponents (blade, tower and shaft) together with the aerodynamic calculations for forces and moments taking into consideration the dynamic stall as well as the dynamic response is developed. This method was applied to a realistic VAWT; namely; the PIONEER I built in the Netherlands by Fokker company. A reasonable agreement between the calculated and field results was predicted.
50
Antar, Elie, Amne El Cheikh, and Michel Elkhoury. "A Dynamic Rotor Vertical-Axis Wind Turbine with a Blade Transitioning Capability." Energies 12, no. 8 (April 16, 2019): 1446. http://dx.doi.org/10.3390/en12081446.
Full textAbstract:
This work presents an optimized design of a dynamic rotor vertical-axis wind turbine (DR VAWT) which maximizes the operational tip-speed ratio (TSR) range and the average power coefficient (Cp) value while maintaining a low cut-in wind velocity. The DR VAWT is capable of mimicking a Savonius rotor during the start-up phase and transitioning into a Darrieus one with increasing rotor radius at higher TSRs. The design exploits the fact that with increasing rotor radius, the TSR value increases, where the peak power coefficient is attained. A 2.5D improved delayed detached eddy simulation (IDDES) approach was adopted in order to optimize the dynamic rotor design, where results showed that the generated blades’ trajectories can be readily replicated by simple mechanisms in reality. A thorough sensitivity analysis was conducted on the generated optimized blades’ trajectories, where results showed that they were insensitive to values of the Reynolds number. The performance of the DR VAWT turbine with its blades following different trajectories was contrasted with the optimized turbine, where the influence of the blade pitch angle was highlighted. Moreover, a cross comparison between the performance of the proposed design and that of the hybrid Savonius–Darrieus one found in the literature was carefully made. Finally, the effect of airfoil thickness on the performance of the optimized DR VAWT was thoroughly analyzed.