TY - GEN
T1 - Efficient response recovery procedures for detailed design of jacket foundations
AU - Nielsen, Martin Bjerre
AU - Jensen, Jacob Fisker
AU - Augustyn, Dawid Jakub
AU - Pedersen, Ronnie
N1 - Conference code: 6
PY - 2016/9
Y1 - 2016/9
N2 - Two efficient system reduction procedures for detailed design of jacket foundations by post-processing of aero-elastic simulation results based on reduced structural models (superelements) are presented. It is illustrated that the full foundation response can be accurately recovered either via a force-controlled approach where the interface forces from the coupled aero-elastic simulations are applied to the non-reduced jacket model along with synchronized hydrodynamic wave loads in a dynamic time simulation, or by direct expansion via the superelement reduction basis. The procedures are illustrated on a coupled aero-elastic model represented by the NREL 5 MW reference wind turbine founded on a comprehensive, high-fidelity jacket model with hydrodynamics defined in Ramboll’s in-house offshore structural analysis program, ROSAP. The performances of both the force-controlled method and the direct expansion approach are compared for superelements based on the Guyan method, the Craig-Bampton method and an augmented Craig-Bampton method. It is shown that the Craig-Bampton method is superior to the Guyan method for dynamic problems irrespective of the recovery method. In particular for cases where wave loads are govern-ing, application of the direct expansion approach calls for the Augmented Craig-Bampton method in order to accurately capture the details of the hydrodynamic loading. It is shown that a compact, yet accurate reduction basis can be obtained by replacing some of the fixed interface modes with load dependent residual vectors.
AB - Two efficient system reduction procedures for detailed design of jacket foundations by post-processing of aero-elastic simulation results based on reduced structural models (superelements) are presented. It is illustrated that the full foundation response can be accurately recovered either via a force-controlled approach where the interface forces from the coupled aero-elastic simulations are applied to the non-reduced jacket model along with synchronized hydrodynamic wave loads in a dynamic time simulation, or by direct expansion via the superelement reduction basis. The procedures are illustrated on a coupled aero-elastic model represented by the NREL 5 MW reference wind turbine founded on a comprehensive, high-fidelity jacket model with hydrodynamics defined in Ramboll’s in-house offshore structural analysis program, ROSAP. The performances of both the force-controlled method and the direct expansion approach are compared for superelements based on the Guyan method, the Craig-Bampton method and an augmented Craig-Bampton method. It is shown that the Craig-Bampton method is superior to the Guyan method for dynamic problems irrespective of the recovery method. In particular for cases where wave loads are govern-ing, application of the direct expansion approach calls for the Augmented Craig-Bampton method in order to accurately capture the details of the hydrodynamic loading. It is shown that a compact, yet accurate reduction basis can be obtained by replacing some of the fixed interface modes with load dependent residual vectors.
KW - Offshore wind turbine foundations
KW - System reduction
KW - Structural dynamics
UR - https://www.researchgate.net/publication/314253223_Efficient_response_recovery_procedures_for_detailed_design_of_jacket_foundations
U2 - 10.1201/9781315641645-341
DO - 10.1201/9781315641645-341
M3 - Article in proceeding
VL - 1
SP - 2060
EP - 2065
BT - Insights and Innovations in Structural Engineering, Mechanics and Computation
PB - Taylor & Francis
T2 - The sixth international conference on structural engineering, mechanics and computation
Y2 - 5 September 2016 through 7 September 2016
ER -