Investigation of response amplitude operators for floating offshore wind turbines : preprint / G.K.V. Ramachandran [and three others].

Format:

Book

Government document

Author/Creator:

Ramachandran, G. K. V., author.

Contributor:

National Renewable Energy Laboratory (U.S.), issuing body.

Series:

Conference paper (National Renewable Energy Laboratory (U.S.)) ; NREL/CP-5000-58098.

NREL/CP ; NREL/CP-5000-58098

Language:

English

Subjects (All):

Offshore wind power plants.

Offshore electric power plants.

Physical Description:

1 online resource (8 pages .) : color illustrations

Place of Publication:

[Golden, Colo.] : National Renewable Energy Laboratory, 2013.

Summary:

This paper examines the consistency between response amplitude operators (RAOs) computed from WAMIT, a linear frequency-domain tool, to RAOs derived from time-domain computations based on white-noise wave excitation using FAST, a nonlinear aero-hydro-servo-elastic tool. The RAO comparison is first made for a rigid floating wind turbine without wind excitation. The investigation is further extended to examine how these RAOs change for a flexible and operational wind turbine. The RAOs are computed for below-rated, rated, and above-rated wind conditions. The method is applied to a floating wind system composed of the OC3-Hywind spar buoy and NREL 5-MW wind turbine. The responses are compared between FAST and WAMIT to verify the FAST model and to understand the influence of structural flexibility, aerodynamic damping, control actions, and waves on the system responses. The results show that based on the RAO computation procedure implemented, the WAMIT- and FAST-computed RAOs are similar (as expected) for a rigid turbine subjected to waves only. However, WAMIT is unable to model the excitation from a flexible turbine. Further, the presence of aerodynamic damping decreased the platform surge and pitch responses, as computed by both WAMIT and FAST when wind was included. Additionally, the influence of gyroscopic excitation increased the yaw response, which was captured by both WAMIT and FAST.

Notes:

Title from title screen (viewed on Apr. 15, 2014).

"July 2013."

"To be presented at the 23rd International Ocean, Offshore and Polar Engineering Conference -- ISOPE 2013, Anchorage, Alaska, June 30-July 5, 2013."

Includes bibliographical references (page 5).

OCLC:

876733755