{
  "id": "0912.1620",
  "version": "v1",
  "published": "2009-12-08T21:57:52.000Z",
  "updated": "2009-12-08T21:57:52.000Z",
  "title": "On bubble clustering and energy spectra in pseudo-turbulence",
  "authors": [
    "J. Martinez",
    "D. Chehata",
    "D. P. M. van Gils",
    "C. Sun",
    "D. Lohse"
  ],
  "journal": "J. Fluid Mech. 650, 287 (2010)",
  "doi": "10.1017/S0022112009993570",
  "categories": [
    "physics.flu-dyn"
  ],
  "abstract": "3D-Particle Tracking (3D-PTV) and Phase Sensitive Constant Temperature Anemometry in pseudo-turbulence--i.e., flow solely driven by rising bubbles-- were performed to investigate bubble clustering and to obtain the mean bubble rise velocity, distributions of bubble velocities, and energy spectra at dilute gas concentrations ($\\alpha \\leq2.2$%). To characterize the clustering the pair correlation function $G(r,\\theta)$ was calculated. The deformable bubbles with equivalent bubble diameter $d_b=4-5$ mm were found to cluster within a radial distance of a few bubble radii with a preferred vertical orientation. This vertical alignment was present at both small and large scales. For small distances also some horizontal clustering was found. The large number of data-points and the non intrusiveness of PTV allowed to obtain well-converged Probability Density Functions (PDFs) of the bubble velocity. The PDFs had a non-Gaussian form for all velocity components and intermittency effects could be observed. The energy spectrum of the liquid velocity fluctuations decayed with a power law of -3.2, different from the $\\approx -5/3$ found for homogeneous isotropic turbulence, but close to the prediction -3 by \\cite{lance} for pseudo-turbulence.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2009-12-08T21:57:52.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "energy spectrum",
      "bubble clustering",
      "pseudo-turbulence",
      "phase sensitive constant temperature anemometry",
      "dilute gas concentrations"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "Journal of Fluid Mechanics",
      "year": 2010,
      "month": "Mar",
      "volume": 650,
      "pages": 287
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2010JFM...650..287M"
    }
  }
}