Induction zone measurements and simulations at Perdigão. Alexander Meyer Forsting, Niels Troldborg, Andreas Bechmann, Nikolas Angelou

Transcription

1 Induction zone measurements and simulations at Perdigão Alexander Meyer Forsting, Niels Troldborg, Andreas Bechmann, Nikolas Angelou

2 Overview The induction zone Power curve measurements The UniTTe project SR WindScanner measurements of the induction zone CFD simulations Conclusion Future work 2 DTU Wind Energy, Technical University of Denmark

3 The induction zone Thrust 3 DTU Wind Energy, Technical University of Denmark

4 Power curve measurements Enercon E-82 What velocity should be used? 4 DTU Wind Energy, Technical University of Denmark

5 Power curve measurements What velocity should be used? 5 DTU Wind Energy, Technical University of Denmark

6 Power curve measurements IEC Free-stream reference point 2-3 D D 6 DTU Wind Energy, Technical University of Denmark

7 Power curve measurements Standard only captures the wind speed the rotor interacts with for an entirely homogenous flow-field IEC D D Assumption breaks down for: Wind turbine arrays Sites in complex terrain or surroundings Large rotor diameters 7 DTU Wind Energy, Technical University of Denmark

8 Unified Turbine Testing - UniTTe Replace met mast by a nacelle mounted lidar and measure inside the induction zone Zephir Ltd 8 DTU Wind Energy, Technical University of Denmark

9 Unified Turbine Testing - UniTTe Replace met mast by a nacelle mounted lidar and measure inside the induction zone Lidars can scan at various ranges and heights Measurements follow the wind direction Potential cost savings as masts become redundant Power curve measurements could be unified for any kind of site Needs a validated model for the induction zone 9 DTU Wind Energy, Technical University of Denmark

10 UniTTe at Perdigão Highly complex site seen as challenging validation case Short-range WindScanner provides data for model validation on a rotorscale Long-range for validating the largescale flow 10 DTU Wind Energy, Technical University of Denmark

11 SRWS - Inflow scanning pattern D = 82 m Hub Height = 78 m Scan durations: Horizontal : 47s Vertical : 26s By R. Menke 11 DTU Wind Energy, Technical University of Denmark

12 Data overview 12 DTU Wind Energy, Technical University of Denmark

13 Videos XWUpEkA 13 DTU Wind Energy, Technical University of Denmark

14 22 min average before SCADA 14 DTU Wind Energy, Technical University of Denmark

15 22 min average after SCADA 15 DTU Wind Energy, Technical University of Denmark

16 Perdigão Simulations 16 DTU Wind Energy, Technical University of Denmark

17 Perdigão site Transect 17 Source: Mann, J., Palma, J. P., Matos, J. C., Angelou, N., Courtney, M., Lea, G. and Vasiljevic, N. (2016). Experimental investigation of flow over a double ridge with several doppler lidar systems, Pres. at 96th 17 American Meteorol. Soc. Annual Meeting, URL: ams.confex.com/ams/96annual/webprogram/paper html DTU Wind Energy, Technical University of Denmark

18 Method Steady RANS-CFD with k-ε-fp turbulence model under neutral stratification Actuator disc representation of the turbine Structured O-mesh: One mesh for all wind directions Follows terrain High resolution around turbine with spacing of D/32 (2.6 m) Terrain discretised over a radius of 17 km around turbine Domain height of 10 km Terrain and roughness is smoothed with grid size 18 DTU Wind Energy, Technical University of Denmark

19 Method Effect of Turbine only 19 DTU Wind Energy, Technical University of Denmark

20 Method Effect of Turbine only Computations for : Uniform Flat Terrain Complex Terrain 20 DTU Wind Energy, Technical University of Denmark

21 Perdigão site - Transect Source: Mann, J., Palma, J. P., Matos, J. C., Angelou, N., Courtney, M., Lea, G. and Vasiljevic, N. (2016). Experimental investigation of flow over a double ridge with several doppler lidar systems, Pres. at 96th American Meteorol. Soc. Annual Meeting, URL: ams.confex.com/ams/96annual/webprogram/paper html DTU Wind Energy, Technical University of Denmark 21

22 CT = 0.89 WD = 53 u-component Uniform Flat Complex 22 DTU Wind Energy, Technical University of Denmark

23 CT = 0.89 WD = 53 u-component Uniform Flat Complex 23 DTU Wind Energy, Technical University of Denmark

24 Perdigão site - Transect Source: Mann, J., Palma, J. P., Matos, J. C., Angelou, N., Courtney, M., Lea, G. and Vasiljevic, N. (2016). Experimental investigation of flow over a double ridge with several doppler lidar systems, Pres. at 96th American Meteorol. Soc. Annual Meeting, URL: ams.confex.com/ams/96annual/webprogram/paper html DTU Wind Energy, Technical University of Denmark 24

25 CT = 0.89 WD = 233 u-component Uniform Flat Complex 25 DTU Wind Energy, Technical University of Denmark

26 CT = 0.89 WD = 233 u-component Uniform Flat Complex 26 DTU Wind Energy, Technical University of Denmark

27 Perdigão site neutral Source: Mann, J., Palma, J. P., Matos, J. C., Angelou, N., Courtney, M., Lea, G. and Vasiljevic, N. (2016). Experimental investigation of flow over a double ridge with several doppler lidar systems, Pres. at 96th American Meteorol. Soc. Annual Meeting, URL: ams.confex.com/ams/96annual/webprogram/paper html DTU Wind Energy, Technical University of Denmark 27

28 Conclusion Highly challenging validation case Overall data quality is fine, but uncertainty can be high for SRWS Might hamper detailed model validation SRWS analysis is delayed due to: Synchronisation Heat Challenging installation Despiking Simulations allow a systematic investigation of the induction zone in complex terrain The shape of the orography becomes important for strong gradients linked to Large vertical velocity component Stabilty effects 28 DTU Wind Energy, Technical University of Denmark

29 Future work Seek more interesting measurement periods and post-process Investigate if a critical terrain gradient exists Include variability of wind direction into validation methodology Include stratification Develop uncertainty model for SRWS 29 DTU Wind Energy, Technical University of Denmark

30 Thanks for your attention! Questions? 30 DTU Wind Energy, Technical University of Denmark