Accession Number:

ADA478647

Title:

Experimental Investigation of Rapid Interface Dynamics in Particulate Media

Descriptive Note:

Final rept. Jun-Nov 2007

Corporate Author:

CHICAGO UNIV IL

Personal Author(s):

Report Date:

2008-02-28

Pagination or Media Count:

8.0

Abstract:

This research investigated nonlinear structural deformations driven by dynamic coupling of mechanical and fluid components in particulate media. The understanding of such deformations is of importance for the performance of Air Force systems. In particular, the interactions with the interstitial fluid, typically air, have been largely neglected in prior studies, yet are likely to become important at high strain rates. Using non-invasive high-speed x-ray and video imaging techniques, the dynamics of rapidly moving interfaces in three-dimensional particulate systems were tracked. Key research objectives achieved were a the development of quantitative x-ray radiography techniques for tracking the local packing density variations inside granular beds, b the detailed characterization of the interactions between moving interface, particulate bed material and interstitial gas, and c the measurement of the drag experienced by fast-moving objects inside fine-grained granular beds both in the presence and the absence of interstitial gas.

Subject Categories:

  • Nuclear Physics and Elementary Particle Physics
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE