Behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud

Shuhei Takahashi, Yuya Hata, Yuji Ohya, Takashi Karasudani, Takanori Uchida

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

To clarify the behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud, called a "Wind-Lens turbine", we conducted a three-dimensional numerical simulation using a large eddy simulation (LES). Since this unique wind turbine consists of not only rotating blades but also a diffuser shroud with a broad-ring brim at the exit periphery, the flow field around the turbine is highly complex and unsteady. Previously, our research group conducted numerical simulations using an actuator-disc approximation, in which the rotating blades were simply modeled as an externalforce on the fluid. Therefore, the detailed flow patterns around the rotating blades and the shroud, including the blade tip vortices, could not be simulated. Instead of an actuator-disc approximation, we used a moving boundary technique in the present CFD simulation to simulate the flow around a rotating blade in order to focus especially on blade tip vortices. The simulation results showed a pair ofvortices consisting of a blade tip vortex and a counter-rotating vortex which was generated between the blade tip and the inner surface of the diffuser. Since these vortices interacted with each other, the blade tip vortex was weakened by the counter-rotating vortex. The results showed good agreement with past wind tunnel experiments.

Original languageEnglish
Pages (from-to)5229-5242
Number of pages14
JournalEnergies
Volume5
Issue number12
DOIs
Publication statusPublished - Jan 1 2012

Fingerprint

Diffuser
Wind Turbine
Blade
Wind turbines
Turbomachine blades
Vortex
Vortex flow
Rotating
Actuator disks
Turbine
Turbines
Actuator
Computer simulation
Large eddy simulation
Numerical Simulation
CFD Simulation
Flow patterns
Wind Tunnel
Moving Boundary
Wind tunnels

All Science Journal Classification (ASJC) codes

  • Computer Science(all)
  • Renewable Energy, Sustainability and the Environment
  • Energy Engineering and Power Technology
  • Energy (miscellaneous)

Cite this

Behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud. / Takahashi, Shuhei; Hata, Yuya; Ohya, Yuji; Karasudani, Takashi; Uchida, Takanori.

In: Energies, Vol. 5, No. 12, 01.01.2012, p. 5229-5242.

Research output: Contribution to journalArticle

Takahashi, Shuhei ; Hata, Yuya ; Ohya, Yuji ; Karasudani, Takashi ; Uchida, Takanori. / Behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud. In: Energies. 2012 ; Vol. 5, No. 12. pp. 5229-5242.
@article{b77bb995422a49d68f64af9c07d91075,
title = "Behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud",
abstract = "To clarify the behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud, called a {"}Wind-Lens turbine{"}, we conducted a three-dimensional numerical simulation using a large eddy simulation (LES). Since this unique wind turbine consists of not only rotating blades but also a diffuser shroud with a broad-ring brim at the exit periphery, the flow field around the turbine is highly complex and unsteady. Previously, our research group conducted numerical simulations using an actuator-disc approximation, in which the rotating blades were simply modeled as an externalforce on the fluid. Therefore, the detailed flow patterns around the rotating blades and the shroud, including the blade tip vortices, could not be simulated. Instead of an actuator-disc approximation, we used a moving boundary technique in the present CFD simulation to simulate the flow around a rotating blade in order to focus especially on blade tip vortices. The simulation results showed a pair ofvortices consisting of a blade tip vortex and a counter-rotating vortex which was generated between the blade tip and the inner surface of the diffuser. Since these vortices interacted with each other, the blade tip vortex was weakened by the counter-rotating vortex. The results showed good agreement with past wind tunnel experiments.",
author = "Shuhei Takahashi and Yuya Hata and Yuji Ohya and Takashi Karasudani and Takanori Uchida",
year = "2012",
month = "1",
day = "1",
doi = "10.3390/en5125229",
language = "English",
volume = "5",
pages = "5229--5242",
journal = "Energies",
issn = "1996-1073",
publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",
number = "12",

}

TY - JOUR

T1 - Behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud

AU - Takahashi, Shuhei

AU - Hata, Yuya

AU - Ohya, Yuji

AU - Karasudani, Takashi

AU - Uchida, Takanori

PY - 2012/1/1

Y1 - 2012/1/1

N2 - To clarify the behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud, called a "Wind-Lens turbine", we conducted a three-dimensional numerical simulation using a large eddy simulation (LES). Since this unique wind turbine consists of not only rotating blades but also a diffuser shroud with a broad-ring brim at the exit periphery, the flow field around the turbine is highly complex and unsteady. Previously, our research group conducted numerical simulations using an actuator-disc approximation, in which the rotating blades were simply modeled as an externalforce on the fluid. Therefore, the detailed flow patterns around the rotating blades and the shroud, including the blade tip vortices, could not be simulated. Instead of an actuator-disc approximation, we used a moving boundary technique in the present CFD simulation to simulate the flow around a rotating blade in order to focus especially on blade tip vortices. The simulation results showed a pair ofvortices consisting of a blade tip vortex and a counter-rotating vortex which was generated between the blade tip and the inner surface of the diffuser. Since these vortices interacted with each other, the blade tip vortex was weakened by the counter-rotating vortex. The results showed good agreement with past wind tunnel experiments.

AB - To clarify the behavior of the blade tip vortices of a wind turbine equipped with a brimmed-diffuser shroud, called a "Wind-Lens turbine", we conducted a three-dimensional numerical simulation using a large eddy simulation (LES). Since this unique wind turbine consists of not only rotating blades but also a diffuser shroud with a broad-ring brim at the exit periphery, the flow field around the turbine is highly complex and unsteady. Previously, our research group conducted numerical simulations using an actuator-disc approximation, in which the rotating blades were simply modeled as an externalforce on the fluid. Therefore, the detailed flow patterns around the rotating blades and the shroud, including the blade tip vortices, could not be simulated. Instead of an actuator-disc approximation, we used a moving boundary technique in the present CFD simulation to simulate the flow around a rotating blade in order to focus especially on blade tip vortices. The simulation results showed a pair ofvortices consisting of a blade tip vortex and a counter-rotating vortex which was generated between the blade tip and the inner surface of the diffuser. Since these vortices interacted with each other, the blade tip vortex was weakened by the counter-rotating vortex. The results showed good agreement with past wind tunnel experiments.

UR - http://www.scopus.com/inward/record.url?scp=84872158884&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84872158884&partnerID=8YFLogxK

U2 - 10.3390/en5125229

DO - 10.3390/en5125229

M3 - Article

VL - 5

SP - 5229

EP - 5242

JO - Energies

JF - Energies

SN - 1996-1073

IS - 12

ER -