Experimental Test of Multi-Stage Vertical-Axis Turbines for Cellular Communication Applications

2012 ◽  
Author(s):  
John Abraham ◽  
Brian Plourde ◽  
Greg Mowry ◽  
Ephraim Sparrow
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Fluid Dynamic ◽  
Turbine Blades ◽  
Vertical Axis ◽  
Power Production ◽  
Cellular Communication ◽  
Vertical Axis Wind Turbine ◽  
Rotating Shaft ◽  
Turbine Design

A multi-year research program has generated a working prototype for a vertical-axis wind turbine that is capable of powering cellular communication equipment. The turbine is designed to be affixed to already existing communication towers and thereby has a reduced cost of installation. The turbine is driven by air drag forces rather than by lift. It has a number of novel features including venting slots that are created to reduce the thrust loading on the communication tower. In addition, contoured caps are affixed to the upper and lower edges of the turbine blades to increase power production. As previously mentioned, the turbine design itself is a drag-based concept rather than the more typical lift-driven devices. The advantages of the drag-based design are: 1. lower startup wind speed, 2. slower rotation and a lessened vibrational load on the tower, 3. less sensitive to wind direction, and 4. it can be aligned with the tower. The design of the device was carried out through a combination of numerical simulation and experimentation. The simulations have evolved from preliminary two-dimensional calculations to a fully three dimensional, unsteady, computational fluid dynamic analysis. Simultaneously, the experiments have included both in-field and wind-tunnel tests of various stages of the turbine design. An outcome of the effort is a third-generation working vertical-axis wind turbine (VAWT) that is currently being evaluated with in-field tests. The results of the tests are positive and confirm the expectations that were developed during the product design phase. The turbine, which can be constructed with various rotor stages, has the capability of producing approximately 2–3 kW of power in wind-speed environments of 12–16 m/s. These power production levels are greatly in excess of that required to fully power the electronics equipment on a typical cellular communication tower. Unfortunately, subsequent tests showed that the turbine production dropped approximately sevenfold. The cause of the decrease in performance was friction in the mechanical components which coupled the rotating shaft to the support structure. This recognition reinforces the importance of low-resistance mechanical design for VAWTs. Another aspect of the turbine design is the specialized electronics which allow the electronics to adapt to local wind speeds and consequently increase the efficiency of the power production.

Computational fluid dynamic analysis of roof-mounted vertical-axis wind turbine with diffuser shroud, flange, and vanes

2018 ◽  
Vol 42 (4) ◽  
pp. 404-415
Author(s):  
H. Abu-Thuraia ◽  
C. Aygun ◽  
M. Paraschivoiu ◽  
M.A. Allard
Keyword(s):  
Wind Turbine ◽  
Urban Areas ◽  
Guide Vane ◽  
Fluid Dynamic ◽  
Vertical Axis ◽  
Power Coefficient ◽  
Small Scale ◽  
Vertical Axis Wind Turbine ◽  
Guide Vanes ◽  
Turbine Design

Advances in wind power and tidal power have matured considerably to offer clean and sustainable energy alternatives. Nevertheless, distributed small-scale energy production from wind in urban areas has been disappointing because of very low efficiencies of the turbines. A novel wind turbine design — a seven-bladed Savonius vertical-axis wind turbine (VAWT) that is horizontally oriented inside a diffuser shroud and mounted on top of a building — has been shown to overcome the drawback of low efficiency. The objective this study was to analyze the performance of this novel wind turbine design for different wind directions and for different guide vanes placed at the entrance of the diffuser shroud. The flow field over the turbine and guide vanes was analyzed using computational fluid dynamics (CFD) on a 3D grid for multiple tip-speed ratios (TSRs). Four wind directions and three guide-vane angles were analyzed. The wind-direction analysis indicates that the power coefficient decreases to about half when the wind is oriented at 45° to the main axis of the turbine. The analysis of the guide vanes indicates a maximum power coefficient of 0.33 at a vane angle of 55°.

Stress Analysis of Various Shaped Blade of Savonius Wind Turbine

2014 ◽  
Author(s):  
Jobaidur R. Khan ◽  
Mosfequr Rahman
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Alternative Energy ◽  
Energy Requirement ◽  
Turbine Blades ◽  
Vertical Axis ◽  
Physical Models ◽  
Vertical Axis Wind Turbine ◽  
Low Wind Speed ◽  
The World

Amidst of high demand of energy, the world is seeking alternative energy sources. Wind alone can fulfill most of the energy requirement of the world by its efficient conversion into energy. On efficiency measurement, Horizontal Axis Wind Turbines (HAWT) is the popular to the researchers, but it works best in places where the wind is not disturbed and has high wind power. The inherent advantage of facing the wind direction, design simplicity, less expensive technology for construction, lower wind start-up speeds, easier maintenance, and relatively quietness are turning the focus to Vertical Axis Wind Turbine (VAWT). The low wind speed and non-smooth wind flow regions are attracted for these machines. Savonius turbine is the simplest form of VAWT and operation is based on the difference of the drag force on its blades. The main objective of this study is to analyze a perfect mixture of new and innovative designs of Savonius turbine blades, which can make VAWT more attractive, efficient, durable and sustainable. This is studied by using blade with different numbers in operating in different wind speed. A Computational Fluid Dynamics (CFD) analysis has been used. 2D CAD models of various VAWT geometries are created and tested with CFD software ANSYS/FLUENT with a similar flow-driven motion in a wind tunnel. These simulations provided the aero-dynamic characteristics like shear stress, velocity distribution and pressure distribution. Some physical models with desired properties needed to be fabricated and tested inside tunnel to find the effect of different shapes in real.

Design and Performance Prediction of Low Cost Vertical Axis Wind Turbine

2015 ◽  
Vol 813-814 ◽  
pp. 1070-1074
Author(s):  
T. Micha Premkumar ◽  
T. Mohan ◽  
Sivamani Seralathan ◽  
A. Sudheer Kumar
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Wind Power ◽  
Energy Demand ◽  
Low Cost ◽  
Turbine Blades ◽  
Three Dimensional ◽  
Vertical Axis ◽  
Load Factor ◽  
Vertical Axis Wind Turbine

The capacity of wind power generation has increased across India due to various activities encouraged by government. Moreover, onshore potential in India is in the order of 100GW. However, the plant load factor is often very low in wind power production. In most of the place, low-rated wind speed is available. Effective utilization of the wind to produce small power will reduces the grid load. There is in need to effectively utilize the available potential to meet the energy demand. The low cost vertical axis wind turbine designed for low rated wind regime has the hybrid of simple Savonius and helical Savonius. Various experimental parameters are measured to check the suitability of the vertical axis wind turbine in the low rated wind speed regions. Numerical simulation are carried out for three dimensional steady flow around the combined Savonius and helical Savonius vertical axis wind turbine blades using ANSYS Fluent(C). Numerical investigation are conducted to study the effect of hybrid combination on performance of the rotor in terms of coefficient of torque, coefficient of power, etc. Self-starting behaviour of the vertical axis wind turbine is improved by using this hybrid vertical axis wind turbine.

scholarly journals A Computational and Experimental Study of a Small-Scale Flat-Shaped Vertical Axis Wind Turbine

2018 ◽  
Vol 7 (4.35) ◽  
pp. 946
Author(s):  
NF. Kadir ◽  
H. Mohamed ◽  
A. Manap
Keyword(s):  
Experimental Study ◽  
Wind Speed ◽  
Wind Turbine ◽  
Turbine Blades ◽  
Vertical Axis ◽  
Angular Speed ◽  
Small Scale ◽  
Vertical Axis Wind Turbine ◽  
Percentage Difference ◽  
Turbine Model

This paper focuses on a computational and experimental study of flat-shaped turbine blades for a small scale Vertical Axis Wind Turbine (VAWT). In the computational analysis, a 2-Dimensional (2D) wind turbine model with three flat blades was designed using Ansys Flu-ent, which is computational fluid dynamics (CFD) software. The wind speed around the blades was simulated in a range of 3 m/s to 8 m/s. Velocity and pressure distributions of the airflow around the blades were then observed. Pressures acting on the blades surface were then averaged and used to estimate the angular speed of the wind turbine model using the principles of torque and moment of inertia. A small-scale prototype was designed, fabricated and tested to validate the simulation result. Testing results show that the wind turbine prototype can rotate with an average speed of 148.8 rpm when having a 3.27 m/s wind speed. At the similar wind speed, the simulation result has estimated the angular speed to be 119 rpm. The percentage difference of the angular speed is about 20%. .  

scholarly journals The strategy of simulation effects of wind speed, variation of turbine blades and it’s interaction to power generated by vertical axis wind turbine using NACA 2412

2017 ◽  
Vol 7 (1.2) ◽  
pp. 246
Author(s):  
Bambang Sugiyono Agus Purwono ◽  
Masroni . ◽  
Awan Setiawan ◽  
Tundung Subali Patma ◽  
Ida Bagus Suardika
Keyword(s):  
Wind Speed ◽  
Wind Energy ◽  
Wind Turbine ◽  
Turbine Blade ◽  
Turbine Blades ◽  
Clean Energy ◽  
Vertical Axis ◽  
Vertical Axis Wind Turbine ◽  
Power Capacity ◽  
Speed Variation

The objective of this paper is to simulate the effects upon the wind speed, variation of turbine blades and interaction of wind speed and variation of turbine blades to the power capacity generated by Vertical Axis Wind Turbine (VAWT) using NACA 2412 and to stratify the power capacity generated by the VAWT simulation. The research backgrounds are the wind-energy potential in Indonesia is about 9.290 MW and has already elaborated by Ministry of Mining, and Energy Resources is about 50 MW. This wind energy is environmentally (clean energy), economically (cheapest), easy to operate and easy to maintain, also renewable energy. The method of analysis is quantitative approach using two way classification (analysis of variance or design of experiments). The research variables are wind speed, variation of turbine blades and this interaction among independent variables and the power capacity as dependent variables. Data wind speed simulation vary from 3 m/s till 6 m/s. The quantity of turbine blades vary from 3 till 8 units. The finding from this research is accepted the null hypothesis or not differ significantly at 5% from each independent variable. The scenario and the parameters during the strategy development use turbine blades, wind speed and power generated by VAWT and the maximum power generated is 16.38 watt. The wind speed is 6 m/s and the number of turbine blade is 4 units. However, the minimum power generated by VAWT is 0.45 watt, the wind speed is 6 m/s and the number of turbine blade is 3 units.

Numerical Studies on the Effect of Cambered Airfoil Blades on Self-Starting of Vertical Axis Wind Turbine Part 1: NACA 0012 and NACA 4415

2015 ◽  
Vol 787 ◽  
pp. 250-254 ◽  
Author(s):  
T. Micha Premkumar ◽  
Sivamani Seralathan ◽  
T. Mohan ◽  
N.N.P. Saran Reddy
Keyword(s):  
Wind Turbine ◽  
Turbine Blades ◽  
Vertical Axis ◽  
Vertical Axis Wind Turbine ◽  
Wind Turbine Blades ◽  
Static Pressure Distribution ◽  
Numerical Studies ◽  
Airfoil Blades ◽  
Torque Values ◽  
Naca 0012

This is Part-1 of the two-part paper in considering the effect of cambered airfoil blades on self-starting of vertical axis wind turbine. Part 1 reports the numerical studies on self-starting of vertical axis wind turbine with comparative studies involving NACA 0012 and cambered airfoil NACA 4415. Part 2 of the paper deals with numerical studies of NACA 0018 and cambered air foil NACA 63415. Darrieus type VAWT is attracting many researchers attention for its inherent advantages and its diversified applications. However, a disadvantage is when the rotor is stationary, no net rotational forces arises, even at high-wind speed. The principal advantage of the vertical axis format is their ability to accept wind from any direction without yawing mechanism. However, self-starting capability is the major drawbacks. Moreover, literatures based on computational analysis involving the cambered airfoil are few only. The objective of this present study is to select the suitable airfoil blades on self-starting of VAWT at low-Reynolds number. The numerical studies are carried out to identify self-starting capability of the airfoil using CFD analysis by studying the flow field over the vertical axis wind turbine blades. The commercial CFD code, ANSYS CFX 13.0© was used for the present studies. Initially, the flow over NACA 0012 was simulated and analyzed for different angles of attacks and similarly carried out for NACA 4415. The contours of static pressure distribution and velocity as well as the force and torque were obtained. Even though the lift force for cambered airfoil NACA 4415 is higher, based on the torque values of the above blade profiles, asymmetrical airfoil NACA 0012 is found to be appropriate for self-starring of VAWT.

Design and performance evaluation of vertical axis wind turbine for wind energy harvesting at railway

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hashwini Lalchand Thadani ◽  
Fadia Dyni Zaaba ◽  
Muhammad Raimi Mohammad Shahrizal ◽  
Arjun Singh Jaj A. Jaspal Singh Jaj ◽  
Yun Ii Go
Keyword(s):  
Wind Speed ◽  
Energy Harvesting ◽  
Wind Energy ◽  
Wind Turbine ◽  
High Speed ◽  
Vertical Axis ◽  
Speed Ratio ◽  
Vertical Axis Wind Turbine ◽  
Modeling Tools ◽  
Content Type

PurposeThis paper aims to design an optimum vertical axis wind turbine (VAWT) and assess its techno-economic performance for wind energy harvesting at high-speed railway in Malaysia.Design/methodology/approachThis project adopted AutoCAD and ANSYS modeling tools to design and optimize the blade of the turbine. The site selected has a railway of 30 km with six stops. The vertical turbines are placed 1 m apart from each other considering the optimum tip speed ratio. The power produced and net present value had been analyzed to evaluate its techno-economic viability.FindingsComputational fluid dynamics (CFD) analysis of National Advisory Committee for Aeronautics (NACA) 0020 blade has been carried out. For a turbine with wind speed of 50 m/s and swept area of 8 m2, the power generated is 245 kW. For eight trains that operate for 19 h/day with an interval of 30 min in nonpeak hours and 15 min in peak hours, total energy generated is 66 MWh/day. The average cost saved by the train stations is RM 16.7 mil/year with battery charging capacity of 12 h/day.Originality/valueWind energy harvesting is not commonly used in Malaysia due to its low wind speed ranging from 1.5 to 4.5 m/s. Conventional wind turbine requires a minimum cut-in wind speed of 11 m/s to overcome the inertia and starts generating power. Hence, this paper proposes an optimum design of VAWT to harvest an unconventional untapped wind sources from railway. The research finding complements the alternate energy harvesting technologies which can serve as reference for countries which experienced similar geographic constraints.

scholarly journals Numerical Simulation of Aerodynamic Performance of Off-grid Small Vertical Axis Wind Turbine

2018 ◽  
Vol 53 ◽  
pp. 02004
Author(s):  
Qiuyun Mo ◽  
Jiabei Yin ◽  
Lin Chen ◽  
Weihao Liu ◽  
Li Jiang ◽  
...  
Keyword(s):  
Wind Turbine ◽  
Turbine Blades ◽  
Vertical Axis ◽  
Aerodynamic Performance ◽  
Velocity Fields ◽  
Compact Model ◽  
Vertical Axis Wind Turbine ◽  
Wind Turbine Blades ◽  
Rotation Domain ◽  
Rng Turbulence Model

In this paper, a 2D off-grid small compact model of vertical axis wind turbine was established. The sliding grid technology, the RNG turbulence model and the Coupld algorithm was applied to simulate the unsteady value of the model's aerodynamic performance. Through the analysis on the flow field at difference moments, the rules about velocity fields, vortices distributions and the wind turbine's total torque were obtained. The results show that: the speed around wind turbine blades have obvious gradient, and the velocity distribution at different times show large differences in the computional domain. In the rotating domain vorticity is large. With away from the rotation domain, vorticity reduced quickly. In the process of rotating for vertical axis wind turbine, the wind turbine's total torque showed alternating positive and negative changes.

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