Experimental Methodologies for the Measurement of Wind Turbines Performance

Wind Turbines are one of the most promising technologies to exploit renewable energy sources, and maybe the one which is the closest to achieve grid parity. Many modeling and experimental research activities are carried out in order to continuously improve devices performance. Another promising sector is small scale turbines, below 100kW installed power, for small installation, domestic use, and to be installed on ships. Moving within this scenario, a 1,5 kW turbine was tested inside a wind tunnel, and the following were measured: forces applied to the tower, angular speed, electric power output, mechanical power involved, and stress induced on the blades. Moreover, the cut in rotor speed and the turbine’s efficiency came as outputs of the activity. After some simple forecast calculations, to establish expected maximum values of physical quantities, the experiment was designed. The method used for acquiring all the values at one time involves a wi-fi device, attached to the rotor, in order to acquire signals coming from strain-gauges placed on the blades, avoiding long and cumbersome transmission lines towards the DAQ, coupled to anemometers, load cells, and a wattmeter. Coordination of operators during the tests had a crucial role in carrying out the procedure correctly. Since the main objects of study were blades, rotor and electric generator, the tower has been replaced with a robust support structure, designed to host and protect load cells and signal conditioners from accidental damage, thus permitting a correct measurement of axial force applied to the rotor and reacting momentum of the generator. The wi-fi device was linked to the rotor, in order to affect its mass and inertia characteristics as less as possible. This required the design of a proper linking structure, which was light and well balanced despite being mechanically resistant. Measured quantities are useful to evaluate the turbine’s performance (efficiency, power curve, cut in speed), and also to validate some fem and multi physics predictive models, that are currently under development, as possible tools for general wind turbines design. The outputs of these tests satisfy the need for a wide range of experimental data. This way of designing tests, the physical quantities involved and the schedule of experiments can be suggested as a valuable operative procedure.

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Editorial

Widening Participation and Lifelong Learning ◽

10.5456/wpll.23.1.1 ◽

2021 ◽

Vol 23 (1) ◽

pp. 1-4

Author(s):

Eva Cendon ◽

John Butcher

Keyword(s):

Further Education ◽

University Education ◽

Small Scale ◽

Widening Participation ◽

The North ◽

Research Activities ◽

International Perspectives ◽

Wide Range ◽

International Sector ◽

The Uk

This general edition of the journal provides insights and results of research employing a wide range of approaches and perspectives on widening participation and lifelong learning. Studies from across the UK and international sector utilise different methodological approaches, and as such are particularly interesting, with diverse methods and ways of analysis, including phenomenographic, narrative, and thematic analysis. Overall, the articles range from exploratory case studies and small-scale research to wider range and broad scale studies, highlighting different facets and perspectives. Furthermore, the articles in this volume cover a broad spectrum of institutions and places involved in widening participation, with an emphasis on the (higher) education sector in the UK balanced by international perspectives. The first seven empirical articles are based on research activities in a secondary school, a youth centre, in further education colleges (usually focusing on post-compulsory secondary or pre-university education), in so-called post-92 universities (new(er) universities, formerly Polytechnics and teacher training colleges), and last but not least in a research intensive Russell Group university. They reported challenges from the specific local contexts of different regions in England, from the South (Chichester) to London to the North (Carlisle), and can usefully be framed in the context of international discussions appearing later in the journal.

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Power Quality Investigation of Distribution Networks Embedded Wind Turbines

Journal of Wind Energy ◽

10.1155/2016/7820825 ◽

2016 ◽

Vol 2016 ◽

pp. 1-17 ◽

Cited By ~ 4

Author(s):

A. Elsherif ◽

T. Fetouh ◽

H. Shaaban

Keyword(s):

Power Systems ◽

Wind Energy ◽

Electric Power ◽

Power Quality ◽

Wind Turbines ◽

Distribution System ◽

Renewable Energy Sources ◽

Distribution Networks ◽

Small Scale ◽

Distributed Resources

In recent years a multitude of events have created a new environment for the electric power infrastructure. The presence of small-scale generation near load spots is becoming common especially with the advent of renewable energy sources such as wind power energy. This type of generation is known as distributed generation (DG). The expansion of the distributed generators- (DGs-) based wind energy raises constraints on the distribution networks operation and power quality issues: voltage sag, voltage swell, voltage interruption, harmonic contents, flickering, frequency deviation, unbalance, and so forth. Consequently, the public distribution network conception and connection studies evolve in order to keep the distribution system operating in optimal conditions. In this paper, a comprehensive power quality investigation of a distribution system with embedded wind turbines has been carried out. This investigation is carried out in a comparison aspect between the conventional synchronous generators, as DGs are widely in use at present, and the different wind turbines technologies, which represent the foresightedness of the DGs. The obtained results are discussed with the IEC 61400-21 standard for testing and assessing power quality characteristics of grid-connected wind energy and the IEEE 1547-2003 standard for interconnecting distributed resources with electric power systems.

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Development of Efficient Small Scale Axial Turbine for Solar Driven Organic Rankine Cycle

Volume 3: Coal, Biomass and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems ◽

10.1115/gt2016-57845 ◽

2016 ◽

Cited By ~ 5

Author(s):

Ayad Al Jubori ◽

Raya K. Al-Dadah ◽

Saad Mahmoud ◽

Khalil M. Khalil ◽

A. S. Bahr Ennil

Keyword(s):

Large Scale ◽

Renewable Energy Sources ◽

Cycle Performance ◽

Working Fluid ◽

Small Scale ◽

Cfd Simulations ◽

Axial Turbine ◽

Working Fluids ◽

Wide Range ◽

Inlet Conditions

Recently, the increase in fossil fuel consumption and associated adverse impact on the environment led to significant interest in renewable energy sources like solar. This paper presents a new methodology that integrates the ORC cycle analysis with modeling of an efficient small scale subsonic axial turbine at low temperature heat sources using wide range of organic working fluids like R123, R134a, R141b, R152a, R245fa, R290 and isobutene. The work involves detailed turbine analysis including 1D mean line approach, extensive 3D CFD simulations and ORC cycle analysis at inlet total pressure ranging from 2–5 bar corresponding to temperature range from 275K–365K to achieve the best turbine and cycle performance. This work provides a more reliable data base for small scale organic working fluids instead of using the map of large scale gas turbine. The numerical simulation was performed using 3D RANS with SST turbulence model in ANSYS-CFX. Using iterative CFD simulations with various working fluids with subsonic inlet conditions, Mach number ranging from 0.6–0.65, results showed that using working fluid R123 for a turbine with mean diameter of 70mm, the maximum isentropic efficiency was 82% and power output 5.66 kW leading to cycle efficiency of 9.5%.

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University Expertise and the Oil and Gas Industry: Development of Cost Effective Solutions to Applied Oil-Spill-Related Research Issues

ASME 1997 Turbo Asia Conference ◽

10.1115/97-aa-054 ◽

1997 ◽

Author(s):

Donald W. Davis ◽

Roland J. Guidry

Keyword(s):

Oil Spill ◽

Oil Spills ◽

Oil Pollution ◽

Selection Process ◽

Oil And Gas Industry ◽

The United States ◽

Small Scale ◽

Research Issues ◽

Research Activities ◽

Wide Range

Immediately after the Exxon Valdez incident, the United States Oil Pollution Act of 1990 was passed. This Act clarified the lines of responsibility associated with future oil spills. In addition to this Federal legislation, Louisiana lawmakers in 1991 enacted the Oil Spill Prevention and Response Act. Financial awards associated with this Act support a wide-range of research activities. Since 1993, 24 projects have been funded. The scope and nature of this research includes: • Oil Spill Awareness through Geoscience Education (OSAGE); • Used Oil Recycling in Louisiana’s Coastal Communities; • Evaluation and Characterization of Sorbents; • Landsat TM and Synthetic Aperture Radar to Facilitate Coastline Delineation; • Environmental Effects and Effectiveness of In-Situ Burning in Wetlands; • Bioremediation Protocol for Small-Scale Oil Spills; • Oil Spill Risk on Louisiana’s Largest Waterway; • River Time-of-Travel Modeling; • Composting Technology for Practical and Safe Remediation of Oil-Spill Residuals; • Predictability of Oceanic and Atmospheric Conditions off the Mississippi Delta; and • Phytoremediation for Oil Spill Cleanup and Habitat Restoration in Louisiana’s Marshes. Each of these projects, and others, are the result of the marriage of industry and university researchers in the identification and solution of applied oil-spill-related problems. The alliance is a good one. Important environmental issues are addressed because the selection process ensures each research initiative has the potential of being implemented by the response community. The work and knowledge gained from these projects is a clear indication of how industry and the university community can function in a collaborative manner to solve important issues — a significant partnership that clearly shows how both can benefit and a model for others to follow.

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Numerical Investigation to Assess an Optimal Blade Profile for the Drag Based Vertical Axis Wind Turbine

Volume 6A: Energy ◽

10.1115/imece2013-64001 ◽

2013 ◽

Cited By ~ 5

Author(s):

Sukanta Roy ◽

Ujjwal K. Saha

Keyword(s):

Renewable Energy ◽

Wind Energy ◽

Wind Turbines ◽

Energy Demand ◽

Computational Study ◽

Flow Behavior ◽

Renewable Energy Sources ◽

Vertical Axis ◽

Small Scale ◽

Vertical Axis Wind Turbine

Rapid depletion rate of fossil fuels with an increasing energy demand and their high emission are imposing the evolution activities in the arena of renewable energy. To meet the future demands of renewable energy sources, wind energy is a very promising concept. In this feature, the drag based vertical axis wind turbines (VAWTs) are suitable for small scale wind energy generation for decentralized locations. However, these turbines have low power and torque coefficients as compared to other wind turbines. Numerous blade shapes have been proposed till now to improve the performance of these turbines. In the present paper, a computational study has been performed to simulate the air-flow over different blade profiles using shear stress transport (SST) k–ω turbulence model. The results obtained are validated with the available experimental data. In the dynamic simulations, the power and torque coefficients are calculated considering the blade arc angle as the variable shape parameter. The effects of drag and lift forces on the variable blade shapes are also studied in static simulations at various angular positions. The present paper tries to demonstrate an effective computational methodology to predict the flow behavior around a drag based VAWT. Through this study, it has been found possible to select an optimal blade shape from the point of its aerodynamic performance.

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Investigation of Turbulence Model Performance in Computational Fluid Dynamics Simulations of Horizontal Axis Wind Turbines

Volume 3: Computational Fluid Dynamics; Micro and Nano Fluid Dynamics ◽

10.1115/fedsm2020-20269 ◽

2020 ◽

Author(s):

Keaton Mullenix ◽

D. Keith Walters ◽

Arturo Villegas ◽

F. Javier Diez

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Wind Turbine ◽

Wind Turbines ◽

Renewable Energy Sources ◽

Critical Role ◽

The United States ◽

Horizontal Axis ◽

Small Scale ◽

Horizontal Axis Wind Turbines

Abstract Wind turbines are critically important in the quest to decrease global dependence on non-renewable energy sources. With the space to add 5M wind turbines, the United States is at the forefront of this transition. Horizontal axis wind turbines (HAWTs) have been studied numerically and experimentally at length. The vast majority of computational fluid dynamics (CFD) studies of HAWTs documented in the open literature have been carried out using two-dimensional simulations. Currently, the available three-dimensional simulations do not provide a comprehensive investigation of the accuracy of different options for modeling of fluid turbulence. In this paper four sets of CFD simulations are carried out using four different turbulence models that are commonly used for engineering level CFD analysis: SST-k-ω, Transition k-kL-ω, Standard k-ε, and Monotonically Integrated Large Eddy Simulation (MILES). These models were compared with experimental performance and coefficient of power results for a small-scale industrial wind turbine with inverse tip speed ratios (λ−1) in the range 0.072–0.144. They were further investigated to highlight the similarities and differences for the prediction of coefficient of pressure and skin friction coefficient. The results showed that no singular model, of the four investigated, was able to consistently predict the power performance with a high degree of accuracy when compared to the experimental results. The models also exhibited both similarities and key differences for the other aspects of flow physics. The results presented in this study highlight the critical role that turbulence modeling plays in the overall accuracy of a CFD simulation, and indicate that end users should be well aware of the uncertainties that arise in CFD results for wind turbine analysis, even when other sources of numerical error have been carefully minimized.

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Informing Ecosystem-Based Fisheries Management from an Indigenous Perspective: The Mōtū Kahawai Fishery

10.26686/wgtn.17142281 ◽

2021 ◽

Author(s):

◽

Kimberley Maxwell

Keyword(s):

Decision Making ◽

Fisheries Management ◽

Large Scale ◽

River Mouth ◽

Well Being ◽

Small Scale ◽

Research Approach ◽

Research Activities ◽

Wide Range ◽

Ecosystem Interactions

<p>Despite agencies striving to manage fisheries sustainably, focusing on large-scale commercial interests and ignoring target species and their wider ecosystem interactions, has depleted or collapsed fisheries globally. Indigenous community well-being, practices, knowledge, and food supplies have also diminished as a result. Fisheries managers are now developing a more combined approach to decision-making, which recognises the social and ecological relationships of fisheries. The Ecosystem Approach to Fisheries encourages fisheries scientists and managers to engage with each other, and with the wider community, and to include information on the wider social and ecological components of fisheries systems in decision-making. This thesis explores an Indigenous fishery by demonstrating how to appropriately gather information from a wide range of sources to inform its management. We focus on a case study fishery for kahawai (Arripis trutta), from the perspective of Te Whānau-a-Hikarukutai/Ngāti Horomoana (TWAH/NH). This Hapū (sub-tribe) is part of the larger Te Whānau-a-Apanui Iwi (tribe) of New Zealand (NZ), who have strong cultural connections to, and a unique system for managing, the Mōtū kahawai fishery. This fishery is a small-scale, land-based, hand-line fishery for a medium-sized pelagic teleost fish based at the Mōtū river mouth, located at Maraenui in the eastern Bay of Plenty, NZ. This research demonstrates holistic ecosystem-based fisheries research as a template for future fisheries research activities. A transdisciplinary research approach, grounded in kaupapa Māori research principles and Māori research ethics, was taken. A strategy was developed to direct engagement with Māori for fisheries research. The existing NZ fisheries management system was defined, and Independent fishery forum plans were identified as the most proactive way to inform the system. A plan can also be used to inform fisheries through other mechanisms; therefore, it is a valuable resource to create. Information on the history, background and value of the fishery was gathered and the Mōtū kahawai fishery identified as a cultural keystone species for TWAH/NH. Kahawai trophic and ecosystem interactions were described from ecology and mātauranga studies. This information was collated in a Hapū plan to inform management of the Mōtū kahawai fishery. This fishery has existed for ca. 600 years and the Hapū wish for it to thrive indefinitely. The Hapū plan will inform wider fisheries management, of Hapū values, practices, and knowledge, to be recognised by the wider community, and to support Hapū rangatiratanga (sovereignty) over the fishery.</p>

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Urban Wind Resource Assessment: A Case Study on Cape Town

Energies ◽

10.3390/en12081479 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1479 ◽

Cited By ~ 4

Author(s):

Gough ◽

Lotfi ◽

Castro ◽

Madhlopa ◽

Khan ◽

...

Keyword(s):

South African ◽

Wind Turbines ◽

Renewable Energy Sources ◽

Cape Town ◽

Economic Benefits ◽

Electricity Demand ◽

Small Scale ◽

Levelized Cost Of Electricity ◽

Demand Profile ◽

Power Curves

As the demand for renewable energy sources energy grows worldwide, small-scale urban wind energy (UWE) has drawn attention as having the potential to significantly contribute to urban electricity demand with environmental and socio-economic benefits. However, there is currently a lack of academic research surrounding realizable UWE potential, especially in the South African context. This study used high-resolution annual wind speed measurements from six locations spanning Cape Town to quantify and analyze the city’s UWE potential. Two-parameter Weibull distributions were constructed for each location, and the annual energy production (AEP) was calculated considering the power curves of four commonly used small-scale wind turbines (SWTs). The two Horizontal Axis Wind Turbines (HAWTs) showed higher AEP and capacity factors than Vertical Axis Wind Turbine (VAWT) ones. A diurnal analysis showed that, during summer, an SWT generates the majority of its electricity during the day, which resembles the typical South African electricity demand profile. However, during winter, the electricity is mainly generated in the early hours of the morning, which does not coincide with the typical load demand profile. Finally, the calculation of Levelized Cost of Electricity (LCOE) showed that SWT generation is more expensive, given current electricity market conditions and SWT technology. The study provides a detailed, large-scale and complete assessment of UWE resources of Cape Town, South Africa, the first of its kind at the time of this work.

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Design and Simulation of a 1 DOF Planetary Speed Increaser for Counter-Rotating Wind Turbines with Counter-Rotating Electric Generators

Energies ◽

10.3390/en12091754 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1754 ◽

Cited By ~ 4

Author(s):

Mircea Neagoe ◽

Radu Saulescu ◽

Codruta Jaliu

Keyword(s):

Wind Turbines ◽

Large Scale ◽

Computing Methodology ◽

Patent Application ◽

Analytical Models ◽

Small Scale ◽

Efficient Operation ◽

Electric Generator ◽

Planetary Gearbox ◽

Electric Generators

The improvement of wind turbine performance poses a constant challenge to researchers and designers in the field. As a result, the literature presents new concepts of wind turbines (WTs), such as: counter-rotating wind turbines (CRWTs) with two coaxial wind rotors revolving in opposite directions, WTs with higher-efficiency and downsized transmission systems, or WTs with counter-rotating electric generators (CREGs). Currently, there are a few solutions of WTs, both containing counter-rotating components; however, they can only be used in small-scale applications. Aiming to extend the use of WTs with counter-rotating wind rotors (CRWRs) and CREGs to medium- and large-scale applications, this paper introduces and analyzes a higher-performance WT solution, which integrates two counter-rotating wind rotors, a 1 degree of freedom (DOF) planetary speed increaser with four inputs and outputs, and a counter-rotating electric generator. The proposed system yields various technical benefits: it has a compact design, increases the output power (which makes it suitable for medium- and large-scale wind turbines) and allows a more efficient operation of the electric generator. The kinematic and static computing methodology, as well as the analytical models and diagrams developed for various case studies, might prove useful for researchers and designers in the field to establish the most advantageous solution of planetary speed increasers for the CRWTs with CREGs. Moreover, this paper extends the current database of WT speed increasers with an innovative concept of 1 DOF planetary gearbox, which is subject to a patent application.

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