{
  "abstract": "Accurate prediction of low-frequency responses is important for the dynamic assessment of floating offshore wind turbines (FOWTs), as second-order difference-frequency wave loads can contribute substantially to platform motions and mooring loads. Their relative importance, however, remains less well established when aerodynamic and hydrodynamic low-frequency excitations coexist under operating conditions. This study develops an efficient time-domain formulation for full difference-frequency quadratic transfer function (QTF) loading using bandwidth truncation and integrates it into a fully coupled model of the IEA 15 MW turbine on the VolturnUS-S semi-submersible platform. Numerical predictions are compared with 1:70-scale real-time hybrid wave-basin experiments covering both irregular wave-only and combined turbulent wind-wave conditions. Three hydrodynamic formulations are compared: linear wave excitation, Newman's approximation, and the full-QTF model. Under wave-only conditions, second-order difference-frequency loading substantially improves the prediction of surge and the associated mooring response, particularly in energetic sea states, with the full-QTF model generally providing the closest agreement with measured low-frequency spectra and peak-amplitude distributions. Under combined wind-wave conditions, low-frequency thrust fluctuations dominate near rated wind speed, reducing the relative importance of difference-frequency wave excitation, whereas its contribution becomes more apparent at higher wind speeds as thrust fluctuations diminish. Overall, the full-QTF model provides the most consistent improvement over the linear and Newman models, with maximum surge standard deviation discrepancy from measurement under the most energetic wave conditions less than 18%, with smaller discrepancies for heave, pitch, and mooring tensions.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.27940",
  "author_total": 4,
  "authors": [
    {
      "name": "Yi Zhang"
    },
    {
      "name": "Tom Tosdevin"
    },
    {
      "name": "Tianning Tang"
    },
    {
      "name": "Peter Stansby"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bwpz7nrsqv7gb.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.27940",
  "fulltext_url": null,
  "id": "bwpz7nrsqv7gb",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.27940",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.flu-dyn"
    ],
    [
      "openalex",
      "2212|Wave and Wind Energy Systems"
    ]
  ],
  "openalex": "W7223147903",
  "pdf_url": "https://arxiv.org/pdf/2610.27940",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-20",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bwpz7nrsqv7gb.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:34:04Z",
      "native_id": "2610.27940",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.27940"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.flu-dyn",
      "subfield": "fluid-dynamics"
    }
  ],
  "title": "Second-order difference-frequency effects on floating wind turbine responses: full-QTF modelling and experimental comparison",
  "title_text": "Second-order difference-frequency effects on floating wind turbine responses: full-QTF modelling and experimental comparison",
  "type": "preprint",
  "updated_at": "2026-10-30T12:34:04Z",
  "url": "https://research.draconitic.com/paper/bwpz7nrsqv7gb",
  "venue": "arXiv",
  "versions": []
}