Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Experimental investigation of the effects of tip-injection on the aerodynamic loads and wake characteristics of a model horizontal axis wind turbine rotor
Download
index.pdf
Date
2014
Author
Abdulrahim, Anas
Metadata
Show full item record
Item Usage Stats
295
views
131
downloads
Cite This
In this study, tip injection is implemented on a model Horizontal Axis Wind Turbine (HAWT) rotor to investigate the power and thrust coefficient variations as well as the wake characteristics. The model wind turbine has a 0.95 m diameter 3-bladed rotor with non-linearly twisted and tapered blades that has NREL S826 profile. The nacelle, hub and the blades are specifically designed to allow pressurized air to pass through and get injected from the tips while the rotor is rotating. The experiments are performed at selected tip speed ratios by placing the turbine at the exit of a 1.7 m diameter open-jet wind tunnel facility. This thesis will present a comparative study of the power and thrust coefficient distributions with Tip Speed Ratio (TSR) for the baseline (no-injection) case as well as for the injection cases. In addition, wake measurements using Constant Temperature Anemometry (CTA) system have been conducted at different axial locations downstream of the rotor plane. Results show that, when there is injection, obtained characteristics have significant differences compared to the baseline case both for the load data showing an increase in power and thrust coefficients for TSR values starting near maximum CP condition up to higher TSR levels as well as for the wake characteristics showing a tip flow region that is radially pushed outwards with increased levels of turbulence occupying wider areas compared to the baseline case. Within the wake zone, it’s observed that the boundary between the wake and the freestream gets wider and more diffused due to tip injection. Finally, tip injection shows a power deficiency in terms of increasing the load data, since we are spending more power on the injected air than we gain. Therefore, it is best used for instantaneous active load control depending on flow conditions and load requirements.
Subject Keywords
Vortex-motion.
,
Aerodynamics.
,
Wind turbines
URI
http://etd.lib.metu.edu.tr/upload/12617752/index.pdf
https://hdl.handle.net/11511/23964
Collections
Graduate School of Natural and Applied Sciences, Thesis
Suggestions
OpenMETU
Core
Experimental Investigation of the Effects of Winglets on the Tip Vortex Behavior of a Model Horizontal Axis Wind Turbine Using Particle Image Velocimetry
Ostovan, Yasar; Akpolat, M. Tugrul; Uzol, Oğuz (2019-02-01)
This study presents an experimental investigation on the effects of winglets on the near wake flow around the tip region and on the tip vortex characteristics downstream of a 0.94 m diameter three-bladed horizontal axis wind turbine (HAWT) rotor. Phase-locked 2D particle image velocimetry (PIV) measurements are performed with and without winglets covering 120 deg of azimuthal progression of the rotor. The impact of using winglets on the flow field near the wake boundary as well as on the tip vortex characte...
Experimental investigation of the effects of different helicopter rotor tip geometries on aerodynamic performance and tip vortex characteristics
Uluocak, Sinem; Hazaveh, Hooman Amiri; Perçin, Mustafa; Akpolat, M Tuğrul; Uzol, Oğuz (Netherlands Association of Aeronautical Engineers; 2018-09-05)
In this study, the effects of different tip geometries (rectangular, anhedral, swept-tapered and swept-tapered-anhedral) on the rotor hover performance and tip vortex characteristics are investigated experimentally. A scaled rotor model set-up, instrumented with thrust and torque sensors, is used for aerodynamic performance measurements in hover and a two-dimensional (2D) particle image velocimetry (PIV) is used to obtain the tip vortex characteristics such as vortex trajectory, maximum tangential velocity,...
Experimental Investigation of Aerodynamics of Flapping-Wing Micro-Air-Vehicle by Force and Flow-Field Measurements
Deng, Shuanghou; Perçin, Mustafa; van Oudheusden, Bas (2016-02-01)
This study explores the aerodynamic characteristics of a flapping-wing micro aerial vehicle (MAV) in hovering configuration by means of force and flowfield measurements. The effects of flapping frequency and wing geometry on force generation were examined using a miniature six-component force sensor. Additional high-speed imaging allowed identification of the notable different deformation characteristics of the flexible wings under vacuum condition in comparison to their behavior in air, illustrating the re...
Experimental Study on the Effects of Winglets on the Performance of Two Interacting Horizontal Axis Model Wind Turbines
Ostovan, Y.; Uzol, Oğuz (2016-10-07)
The focus of this experimental study is to investigate the effects of winglets on the performance of two interacting similar horizontal axis model wind turbines. For this purpose, a downwind winglet is designed and manufactured to be attached to the blade tips of the upstream turbine. A set of wing extensions with the same length as the winglets is also produced to be compared to the winglets. Power and thrust coefficients of both turbines are measured with winglets as well as with wing extensions attached ...
Genetic Algorithm based aerodynamic shape optimization tool for wind turbine blades and its implementation to helicopter blades
Polat, Özge; Sezer-uzol, Nilay; Tuncer, İsmail Hakkı (2014-01-01)
This study presents a methodology first built up for the aerodynamic shape optimization for wind turbine rotors and its modified version for a helicopter rotor in hover. The Genetic Algorithm (GA) coupled with an in-house Blade Element Momentum (BEM) tool is used in the design optimization process. The wind turbine blade optimization studies are performed for maximizing the power production at a given wind speed, rotor speed and rotor diameter, while for the helicopter blade optimization in hover, figure of...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
A. Abdulrahim, “Experimental investigation of the effects of tip-injection on the aerodynamic loads and wake characteristics of a model horizontal axis wind turbine rotor,” M.S. - Master of Science, Middle East Technical University, 2014.
