SCALING AND DYNAMICS OF IMPACTS INTO DENSE SUSPENSIONS

Authors
Brassard, Marc-Andre
Subjects
dense suspensions
impacts
liquid armor
non-Newtonian fluids
Advisors
Clark, Abram H., IV
Date of Issue
2020-06
Date
Publisher
Monterey, CA; Naval Postgraduate School
Language
Abstract
Dense suspensions, which consist of sub-millimeter particles suspended in a Newtonian fluid, undergo a dramatic solidification when subjected to sudden impact, as first described in M.A. Brassard et al.’s article in the 2020 Bulletin of the American Physical Society. The underlying physical mechanisms for this effect are not known. Recently, a class of added mass models has been proposed to explain this phenomenon. These models give direct predictions on the times and magnitudes associated with the peak stresses during impacts, including how these stresses vary with changes to the intruder mass and size. In this thesis, we performed impact experiments in cornflour and water dense suspensions. We varied the size, speed, mass and shape of the intruder and quantified the forces and times via high-speed imaging and acceleration sensors. We used dimensional and scaling analysis to confirm or disprove added mass models, and the aim is for our results to be used to test current theories and help derive future theories to explain impact-induced solidification in dense suspensions.
Type
Thesis
Description
Department
Physics (PH)
Organization
Identifiers
NPS Report Number
Sponsors
Funder
Format
Citation
Distribution Statement
Approved for public release. distribution is unlimited
Rights
Copyright is reserved by the copyright owner.