{
  "abstract": "The kinetic energy budget of a laminar separation bubble on a compressor blade is formed mode by mode in frequency and spanwise wavenumber from a direct numerical simulation at a Reynolds number of $2.5\\times10^{5}$ based on the axial chord. The nonlinear transfer between modes is evaluated as a triadic tensor that gives the energy exchanged in every triad, the roles of its three modes, and the location of the exchange. Nine dominant tonal modes are identified: the flapping of the bubble, the Kelvin-Helmholtz mode with its sidebands, a pair of modes near reattachment, and their sum, difference, and harmonic. They hold 8% of the fluctuation energy, and their triads are responsible for 19% of the energy exchanged. Every tonal mode is fed by the mean shear and exports 69 to 82% of the energy it takes from the mean flow. The Kelvin-Helmholtz mode sends 45% of the energy it sheds to lower frequencies. The largest of these transfers is a triad in which it acts as a catalyst. The exchange in each triad is split into nine channels by velocity components. In every triad of spanwise-uniform modes, one channel dominates: the wall-tangential velocity of the donor advected by the wall-normal velocity of the catalyst. For a pair of oblique modes, the same advection by the two-dimensional Kelvin-Helmholtz mode exchanges their spanwise velocity, which the mean flow cannot produce. The rollers thus become three-dimensional through the advecting velocity of the Kelvin-Helmholtz mode, which supplies no energy to the exchange.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.27035",
  "author_total": 4,
  "authors": [
    {
      "name": "Gustavo Lopes"
    },
    {
      "name": "Pawel Przytarski"
    },
    {
      "name": "Daniele Simoni"
    },
    {
      "name": "Davide Lengani"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2dnjzspkhhgwh.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.27035",
  "fulltext_url": null,
  "id": "2dnjzspkhhgwh",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.27035",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.flu-dyn"
    ],
    [
      "openalex",
      "2206|Fluid Dynamics and Turbulent Flows"
    ]
  ],
  "openalex": "W7223145273",
  "pdf_url": "https://arxiv.org/pdf/2610.27035",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2dnjzspkhhgwh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:22Z",
      "native_id": "2610.27035",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.27035"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.flu-dyn",
      "subfield": "fluid-dynamics"
    }
  ],
  "title": "Triadic energy routes in a short laminar separation bubble",
  "title_text": "Triadic energy routes in a short laminar separation bubble",
  "type": "preprint",
  "updated_at": "2026-11-01T12:20:44Z",
  "url": "https://research.draconitic.com/paper/2dnjzspkhhgwh",
  "venue": "arXiv",
  "versions": []
}