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SUMMARY:Investigations on wind turbine wakes: wind tunnel tests and field 
 experiments with LiDARs
DTSTART:20111018T161500
DTSTAMP:20260916T225821Z
UID:82f7a73b19dac92f94c53dff4a5c6736e1db8af20d59741e07d5b491
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr Valerio Iungo\, WIRE-ENAC\nWind energy has been growing rap
 idly in the last few decades and is becoming one of the most profitable so
 urce of renewable energy\, thus more efficient and optimized wind energy s
 ystems are needed. Investigations on wake flows produced from the interact
 ion between atmospheric boundary layer and wind turbines can be carried ou
 t with numerical simulations\; however\, all numerical tools need a signif
 icant amount of experimental data for their assessment and validation. Exp
 erimental investigations on wind turbines mainly consist of wind tunnel te
 sts and field measurements of real wind turbines: the former presents the 
 advantage of reproducing a broad range of well characterized wind conditio
 ns\, but the down-scaled models used for these investigations can represen
 t a strong limitation due to a lower Reynolds number with respect to real 
 conditions. On the other hand field measurements of real wind turbines sti
 ll represent a challenging task due to the large measurement volumes invol
 ved and to the high financial effort. In this study wind tunnel investigat
 ions carried out by using hot-wire anemometry and multi-hole pressure prob
 es are presented. Analysis of the development of wind turbine wakes by mov
 ing downstream and of the evolution of turbulence highlights that wind tur
 bine wakes are characterized by a strong velocity defect in the proximity 
 of the rotor\; moreover\, the wake velocity defect and the cross-dimension
  of the wake are found to be related to wind turbine performance. Besides 
 wind tunnel tests\, field measurements of wake flows produced from two 2 M
 W wind turbines located in Valais\, Switzerland\, are performed with three
  wind LiDARs. Bi-dimensional scans are performed in order to analyse wind 
 turbine wakes and simultaneous measurements with two or three LIDARs allow
  the reconstruction of multi-component velocity fields.  Interestingly\, b
 oth LiDAR and wind tunnel measurements highlight the presence of an increa
 sed turbulence level at the top-tip of the wind turbine blades\, which can
  represent dangerous fatigue loads on following wind turbines within a win
 d farm.
LOCATION:GR C0 01
STATUS:CONFIRMED
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