Comparing rotor plane induction determined from full-scale measurements and CFD simulations

Amin Ghadirian*, Gunner Chr Larsen, Niels Troldborg

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

1 Downloads (Pure)

Abstract

This paper investigates the flow field in the rotor plane of a full-scale operating wind turbine using full-scale light detection and ranging (LiDAR) measurements for the first time. Comparison of the measured flow field with results from large eddy simulations (LES) combined with an actuator line approach is also presented for in-depth study of the induction field in the rotor plane. The measurements include data from two synchronized LiDAR systems—one scanning the undisturbed upstream inflow field and one measuring in the rotor plane. The standard deviation of the mean of velocity time series are and presented as a measure of reliability. The method for calculating the axial velocity based on the line-of-sight velocity is explained and the uncertainty of such method is presented. The process of calculating the yaw misalignment is described. The time-averaged and phase-averaged axial velocity and induction factors are presented relative to radius and azimuth, and the general behavior is described relative to the flow regimes around the blades, tower and nacelle. Simulations and measurements are compared with special emphasis on the flow structures in the vicinity of the individual rotor blades. A convincing agreement between measurements and simulations is demonstrated. The uncertainties originated from the imprecise positions and angles of the measurement instruments are shown. The uncertainties are limited to the middle parts of the blades between 15 m to 25 m from the root. In addition, longer selected time series show smaller uncertainties. This proves the reliability of the application of the methodology for even longer time series.

Original languageEnglish
JournalWind Energy
Volume22
Issue number1
Pages (from-to)109-123
ISSN1095-4244
DOIs
Publication statusPublished - 2019

Keywords

  • Actuator line
  • CFD
  • LiDAR
  • Rotor plane flow
  • Spinner LiDAR

Cite this

@article{e7b4440906db4df99078ebfdb1534b82,
title = "Comparing rotor plane induction determined from full-scale measurements and CFD simulations",
abstract = "This paper investigates the flow field in the rotor plane of a full-scale operating wind turbine using full-scale light detection and ranging (LiDAR) measurements for the first time. Comparison of the measured flow field with results from large eddy simulations (LES) combined with an actuator line approach is also presented for in-depth study of the induction field in the rotor plane. The measurements include data from two synchronized LiDAR systems—one scanning the undisturbed upstream inflow field and one measuring in the rotor plane. The standard deviation of the mean of velocity time series are and presented as a measure of reliability. The method for calculating the axial velocity based on the line-of-sight velocity is explained and the uncertainty of such method is presented. The process of calculating the yaw misalignment is described. The time-averaged and phase-averaged axial velocity and induction factors are presented relative to radius and azimuth, and the general behavior is described relative to the flow regimes around the blades, tower and nacelle. Simulations and measurements are compared with special emphasis on the flow structures in the vicinity of the individual rotor blades. A convincing agreement between measurements and simulations is demonstrated. The uncertainties originated from the imprecise positions and angles of the measurement instruments are shown. The uncertainties are limited to the middle parts of the blades between 15 m to 25 m from the root. In addition, longer selected time series show smaller uncertainties. This proves the reliability of the application of the methodology for even longer time series.",
keywords = "Actuator line, CFD, LiDAR, Rotor plane flow, Spinner LiDAR",
author = "Amin Ghadirian and Larsen, {Gunner Chr} and Niels Troldborg",
year = "2019",
doi = "10.1002/we.2274",
language = "English",
volume = "22",
pages = "109--123",
journal = "Wind Energy",
issn = "1095-4244",
publisher = "JohnWiley & Sons Ltd.",
number = "1",

}

Comparing rotor plane induction determined from full-scale measurements and CFD simulations. / Ghadirian, Amin; Larsen, Gunner Chr; Troldborg, Niels.

In: Wind Energy, Vol. 22, No. 1, 2019, p. 109-123.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Comparing rotor plane induction determined from full-scale measurements and CFD simulations

AU - Ghadirian, Amin

AU - Larsen, Gunner Chr

AU - Troldborg, Niels

PY - 2019

Y1 - 2019

N2 - This paper investigates the flow field in the rotor plane of a full-scale operating wind turbine using full-scale light detection and ranging (LiDAR) measurements for the first time. Comparison of the measured flow field with results from large eddy simulations (LES) combined with an actuator line approach is also presented for in-depth study of the induction field in the rotor plane. The measurements include data from two synchronized LiDAR systems—one scanning the undisturbed upstream inflow field and one measuring in the rotor plane. The standard deviation of the mean of velocity time series are and presented as a measure of reliability. The method for calculating the axial velocity based on the line-of-sight velocity is explained and the uncertainty of such method is presented. The process of calculating the yaw misalignment is described. The time-averaged and phase-averaged axial velocity and induction factors are presented relative to radius and azimuth, and the general behavior is described relative to the flow regimes around the blades, tower and nacelle. Simulations and measurements are compared with special emphasis on the flow structures in the vicinity of the individual rotor blades. A convincing agreement between measurements and simulations is demonstrated. The uncertainties originated from the imprecise positions and angles of the measurement instruments are shown. The uncertainties are limited to the middle parts of the blades between 15 m to 25 m from the root. In addition, longer selected time series show smaller uncertainties. This proves the reliability of the application of the methodology for even longer time series.

AB - This paper investigates the flow field in the rotor plane of a full-scale operating wind turbine using full-scale light detection and ranging (LiDAR) measurements for the first time. Comparison of the measured flow field with results from large eddy simulations (LES) combined with an actuator line approach is also presented for in-depth study of the induction field in the rotor plane. The measurements include data from two synchronized LiDAR systems—one scanning the undisturbed upstream inflow field and one measuring in the rotor plane. The standard deviation of the mean of velocity time series are and presented as a measure of reliability. The method for calculating the axial velocity based on the line-of-sight velocity is explained and the uncertainty of such method is presented. The process of calculating the yaw misalignment is described. The time-averaged and phase-averaged axial velocity and induction factors are presented relative to radius and azimuth, and the general behavior is described relative to the flow regimes around the blades, tower and nacelle. Simulations and measurements are compared with special emphasis on the flow structures in the vicinity of the individual rotor blades. A convincing agreement between measurements and simulations is demonstrated. The uncertainties originated from the imprecise positions and angles of the measurement instruments are shown. The uncertainties are limited to the middle parts of the blades between 15 m to 25 m from the root. In addition, longer selected time series show smaller uncertainties. This proves the reliability of the application of the methodology for even longer time series.

KW - Actuator line

KW - CFD

KW - LiDAR

KW - Rotor plane flow

KW - Spinner LiDAR

U2 - 10.1002/we.2274

DO - 10.1002/we.2274

M3 - Journal article

AN - SCOPUS:85053521378

VL - 22

SP - 109

EP - 123

JO - Wind Energy

JF - Wind Energy

SN - 1095-4244

IS - 1

ER -