FY2011 Annual Report

Continuum Physics Unit

Professor Gustavo Gioia

Abstract

After joining the OIST faculty on 15 January 2012, Gioia pursued research on granular materials, turbulence, and tropical cyclones.

1. Staff

  • Dr. Gioia Gustavo, Professor
  • Kaori Egashira, Research Administrator

2. Collaborations

  • Theme: Turbulence
    • Type of collaboration: Scientific Collaboration
    • Researchers:
      • Professor, Pinaki Chakraborty, Fluid Mechanics, OIST
      • Professor, Nigel Goldenfeld, Physics, University of Illinois at Urbana-Champaign
      • Professor, Walter Goldburg, Physics & Astronomy, University of Pittsburgh
      • Professor, Hamid Kellay, Physics, University of Bordeaux
  • Theme: Tropical cyclones
    • Type of collaboration: Scientific Collaboration
    • Researchers:
      • Professor, Pinaki Chakraborty, Fluid Mechanics, OIST

3. Activities and Findings

3.1

We have carried out measurements of force-penetration curves and (via X-ray tomography) density fields in cohesive granular aggregates under punching. These experimental measurements are being used to test a theory in which aggregate densification by particle rearragement takes the form of a phase transition.

3.2

We have carried out frictional-drag measurements in a new soap-film channel in which for the first time it is possible to realize turbulent soap-film flows with an unambiguous spectral exponent of 5/3 (the spectral exponent that prevails in ordinary three-dimensional pipe flows). These experimental measurements are being used as part of a long-term project aimed at verifying the predictions of an unprecedented spectral theory of the frictional drag in turbulent flows. This is a collaborative project with the Fluid Mechanics Unit.

3.3

We have computed satellite-based estimates of precipitation in tropical cylones and used them to test the predictions of a thermodynamic model of tropical cyclones. This is a collaborative project with the Fluid Mechanics Unit.

3.4

We are currently building a research group and establishing a joint fluid mechanics-continuum physics laboratory at OIST.

4. Publications

4.1 Journals

R.F. Shepherd, J.C. Conrad, T. Sabuwala, G. Gioia, and J.A. Lewis, “Structural evolution of cuboidal granular media”, Soft Matter 8, 4795-4801 (2012)

4.2 Books and other one-time publications

Nothing to report

4.3 Oral and Poster Presentations

Alexei P., Tapan, S., Gustavo, G. Cohesive granular aggregates under punching: theory and experiments, American Physical Society March Meeting, Boston, Massachusetts, USA, March 1, 2012

5. Intellectual Property Rights and Other Specific Achievements

Nothing to report

6. Meetings and Events

American Physical Society March Meeting; Boston, Massachusetts, USA, March 2012

7. Other

Nothing to report.