The Library
Liquid marble formation : development of a computational model from experiments
Tools
Pritchard, Jesse (2021) Liquid marble formation : development of a computational model from experiments. PhD thesis, University of Warwick.
|
PDF
WRAP_Theses_Pritchard_2021.pdf - Submitted Version - Requires a PDF viewer. Download (52Mb) | Preview |
Official URL: http://webcat.warwick.ac.uk/record=b3736801
Abstract
This thesis presents novel experimental and computational modelling investigations of liquid marble formation via drop impact onto a superhydrophobic powder bed. A mathematical model is formulated for this process, and following numerical implementation, the first reporting of simulations for liquid marble formation via drop impact is made, for a wide range of impact Weber numbers. These simulations are validated by comparison to drop impact experiments.
The adhered particle coating on the surface of the impacted drop creates energy dissipating effects, which are captured by a model based on incorporating a surface viscosity with a dominant dilatational component. Following physically-motivated simplifying assumptions, surface viscous effects appear via a spatially independent effective surface tension, which differs from the usual value only after the drop is completely encapsulated in particles. Following analysis of the experimental data, a novel relationship is identified between the maximum spreading diameter of the drop with the powder bed, and the surface area of the drop when it becomes encapsulated, and when (and if) it becomes a deformed liquid marble due to particle jamming at its interface. This relationship is used in the model to provide a constitutive equation for the surface viscous effects, and to identify encapsulation and deformed liquid marble formation in simulations.
Additionally, a novel third-order damped oscillator model is derived for a suspended inviscid oscillating drop experiencing the effects of a dilatational component of surface viscosity. This model predicts that with a sufficiently large dilatational surface viscous coefficient, a transition from overdamped to underdamped motion occurs over the course of a drop's oscillations, which is not predicted in existing (linear) approximations, and is validated following numerical simulations. For small amplitude oscillations, an analytic solution for the motion in the overdamped limit is derived, and an analogue of the effective surface tension is presented.
Item Type: | Thesis (PhD) | ||||
---|---|---|---|---|---|
Subjects: | Q Science > QA Mathematics Q Science > QC Physics |
||||
Library of Congress Subject Headings (LCSH): | Marble -- Mathematical models, Fluid dynamics -- Drops -- Mathematical models, Drops, Fluid-structure interaction, Surfaces (Technology), Solids -- Surfaces | ||||
Official Date: | January 2021 | ||||
Dates: |
|
||||
Institution: | University of Warwick | ||||
Theses Department: | Mathematics Institute | ||||
Thesis Type: | PhD | ||||
Publication Status: | Unpublished | ||||
Supervisor(s)/Advisor: | Sprittles, James E. ; Chubynsky, Mykyta | ||||
Sponsors: | Engineering and Physical Sciences Research Council | ||||
Format of File: | |||||
Extent: | xxix, 337 leaves : illustrations | ||||
Language: | eng |
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |
Downloads
Downloads per month over past year