Impact Response Of Fluid-Saturated Granular Beds And Dense Suspensions
Abstract
Systems of sub-millimeter solid particles immersed in a simple fluid can exhibit a dramatic increase inflow resistance when they are rapidly sheared, often called discontinuous shear thickening (DST). A related process is impact-induced solidification, which occurs when an intruder is driven into a particle-fluid mixture. The resultant hardening is sufficient to dampen the movement of the intruder to essentially stop it in a distance much shorter than it would in other fluids. However, the fundamental physical processes that give rise to these behaviors are not well understood. An improved description would have several military applications, such as under-vehicle armor and pipe jacketing. It also could provide a better understanding of how mines interact with wet soils. This thesis presents a fundamental experimental and theoretical study of low-speed impacts into systems of glass beads of varying sizes mixed with water. Our results show that current models fail to capture many aspects of the behavior (e.g., how the peak stresses during impact depend on the initial impact speed and the particle diameter), suggesting that new theoretical descriptions are needed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2020
- Accession Number
- AD1114629
Entities
People
- Neil A. Causley
Organizations
- Naval Postgraduate School