TY - JOUR

T1 - Hierarchical four-step global sensitivity analysis of offshore wind turbines based on aeroelastic time domain simulations

AU - Hübler, Clemens

AU - Gebhardt, Cristian Guillermo

AU - Rolfes, Raimund

N1 - Funding information: We gratefully acknowledge the financial support of the European Commission (research project IRPWIND, funded from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement number 609795) that enabled this work. This work was supported by the compute cluster which is funded by Leibniz Universität Hannover, the Lower Saxony Ministry of Science and Culture (MWK), and the German Research Foundation (DFG).

PY - 2017/5/4

Y1 - 2017/5/4

N2 - Although uncertainties are present in all real parameters, numerical calculations of the structural behaviour of offshore wind turbines are usually conducted with deterministic values. However, with this approach, optimisation processes can be misleading and reliability levels cannot be calculated. The reasons for deterministic calculations are high computing times of probabilistic approaches and the lack of knowledge about the scatter of data. For deterministic approaches, more complex models with higher computing times are possible, although they, are less generally valid. Therefore, it is useful to identify the most influential parameters that have to be treated in a probabilistic manner using sensitivity analyses is valuable. Contrary to rudimentary sensitivity approaches being used in offshore wind energy so far, this paper presents a new four-step sensitivity analysis reducing the probabilistic parameter subset step by step and aiming to achieve a compromise between computing time and complexity. It can be shown that for different substructures and different load cases, only a small parameter subset is influential and many other inputs can be regarded as deterministic without losing accuracy. However, attention must be paid to the slight differences among substructures. Therefore, it must be highlighted that not all results are general.

AB - Although uncertainties are present in all real parameters, numerical calculations of the structural behaviour of offshore wind turbines are usually conducted with deterministic values. However, with this approach, optimisation processes can be misleading and reliability levels cannot be calculated. The reasons for deterministic calculations are high computing times of probabilistic approaches and the lack of knowledge about the scatter of data. For deterministic approaches, more complex models with higher computing times are possible, although they, are less generally valid. Therefore, it is useful to identify the most influential parameters that have to be treated in a probabilistic manner using sensitivity analyses is valuable. Contrary to rudimentary sensitivity approaches being used in offshore wind energy so far, this paper presents a new four-step sensitivity analysis reducing the probabilistic parameter subset step by step and aiming to achieve a compromise between computing time and complexity. It can be shown that for different substructures and different load cases, only a small parameter subset is influential and many other inputs can be regarded as deterministic without losing accuracy. However, attention must be paid to the slight differences among substructures. Therefore, it must be highlighted that not all results are general.

KW - FAST

KW - Global sensitivity

KW - Offshore substructures

KW - Time domain simulations

KW - Wind energy

UR - http://www.scopus.com/inward/record.url?scp=85019049140&partnerID=8YFLogxK

U2 - 10.1016/j.renene.2017.05.013

DO - 10.1016/j.renene.2017.05.013

M3 - Article

AN - SCOPUS:85019049140

VL - 111

SP - 878

EP - 891

JO - Renewable energy

JF - Renewable energy

SN - 0960-1481

ER -