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DOE OSTI · 1659881

Superelement reduction of substructures for sequential load calculations in OpenFAST

Branlard, E.·Shields, M.·Anderson, B.·Damiani, R.·Wendt, F.·Jonkman, J.·Musial, W.·Foley, B.
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Abstract

This article presents the superelement formulation newly implemented in OpenFAST to simulate fixed-bottom substructures with a reduced-order model similar to a common industry practice. The Guyan and Craig-Bampton methods are used to reduce the number of degrees of freedom and generate a so-called "superelement". The formulation allows manufacturers to exchange such superelements to perform load calculations without revealing sensitive information about the support structure (e.g., foundation, substructure, and/or tower) or turbine. The source code is made publicly available in the OpenFAST repository. Test cases with varying degrees of complexity are presented to validate the technique, and accuracy issues are discussed.

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Branlard, E., Shields, M., Anderson, B., Damiani, R., Wendt, F., Jonkman, J., Musial, W., Foley, B.. 2020-03-04. Superelement reduction of substructures for sequential load calculations in OpenFAST. https://doi.org/10.1088/1742-6596%2F1452%2F1%2F012033

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