Geometrically nonlinear wind turbine blade reduced order model

Geometrically nonlinear wind turbine blade reduced order model based on modal derivatives Ozan Gözcü (ozgo@dtu. dk) 17/06/2019 DTU Wind Energy Science Conference 2019

Outline • Introduction • Methodology – Modal derivatives – Non-intrusive method • Results – Straight beam – NREL 5 MW turbine blade – DTU 10 MW turbine blade • Conclusion 17/06/2019 DTU Wind Energy Science Conference 2019 2

Introduction DTU Wind Blade Test Facility NREL 5 MW Blade FE model Blade beam model for load analysis 17/06/2019 DTU Wind Energy Science Conference 2019 3

Modal Derivatives 17/06/2019 DTU Wind Energy Science Conference 2019 Slide 4

Modal Derivatives 17/06/2019 DTU Wind Energy Science Conference 2019 Slide 5

Methodology • Intrusive method • Non-intrusive method 17/06/2019 DTU Wind Energy Science Conference 2019 Slide 6

Straight Beam 5 cm E = 70 Mpa 1 meter X 10 cm Z P = 10 e 3 N Y Last node displacement X [m] 17/06/2019 DTU Wind Energy Z [m] HAWC 2 0. 1892 -0. 02053 MD 0. 1900 -0. 02038 Linear 0. 1952 Linear + MD 0. 1952 -0. 02150 Wind Energy Science Conference 2019 0. 0 Slide 7

Straight Beam X Load : Px = Py = 10 e 3 N Z Y Last node displacement and torsion 17/06/2019 DTU Wind Energy X [m] Y [m] Z [m] HAWC 2 0. 1885 0. 0485 -0. 02173 0. 139 o MD 0. 1894 0. 0485 -0. 02156 0. 122 o Linear 0. 1952 0. 0492 0. 0 o Wind Energy Science Conference 2019 Torsion Slide 8

NREL 5 MW Blade 61. 5 meters Last node displacement and torsion X [m] 17/06/2019 DTU Wind Energy Y [m] Z [m] Torsion HAWC 2 0. 969 9. 928 -1. 403 0. 052 o MD 0. 950 9. 353 -1. 193 0. 077 o Linear 1. 364 12. 715 0. 0 -0. 974 o Wind Energy Science Conference 2019 Slide 9

DTU 10 MW Blade 86. 4 meters 3. 3 meters Last node displacement and torsion X [m] 17/06/2019 DTU Wind Energy Y [m] Z [m] Torsion HAWC 2 1. 957 15. 631 -1. 558 -2. 805 o MD 1. 969 14. 939 -1. 229 -2. 602 o Linear 1. 858 15. 865 1. 022 -3. 058 o Wind Energy Science Conference 2019 Slide 10

Conclusion • Static modal derivatives of the models are computed • Cubic and quadratic stiffness terms are computed by non-intrusive method • A geometrically non-linear reduced order models are constructed by modal derivatives and non-linear stiffness terms • The reduced order models are tested under static loads. Results show that the models work well under static load cases Future work • The ROM will be implemented into HAWC 2 for turbine load analysis • I will work on the possible improvements of the method 17/06/2019 DTU Wind Energy Science Conference 2019 Slide 11

Slide 12