Journal ArticleDOI
Moving contact lines and rivulet instabilities. Part 1. The static rivulet
TLDR
In this paper, a linearized stability theory for small, static rivulets whose contact (common or three-phase) lines (i) are fixed, (ii) move but have fixed contact angles or (iii) have contact angles smooth functions of contact-line speeds is presented.Abstract:
A rivulet is a narrow stream of liquid located on a solid surface and sharing a curved interface with the surrounding gas. Capillary instabilities are investigated by a linearized stability theory. The formulation is for small, static rivulets whose contact (common or three-phase) lines (i) are fixed, (ii) move but have fixed contact angles or (iii) move but have contact angles smooth functions of contact-line speeds. The linearized stability equations are converted to a disturbance kinetic-energy balance showing that the disturbance response exactly satisfies a damped linear harmonic-oscillator equation. The ‘damping coefficient’ contains the bulk viscous dissipation, the effect of slip along the solid and all dynamic effects that arise in contact-line condition (iii). The ‘spring constant’, whose sign determines stability or instability in the system, incorporates the interfacial area changes and is identical in cases (ii) and (iii). Thus, for small disturbances changes in contact angle with contact-line speed constitute a purely dissipative process. All the above results are independent of slip model at the liquid–solid interface as long as a certain integral inequality holds. Finally, sufficient conditions for stability are obtained in all cases (i), (ii) and (iii).read more
Citations
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Journal ArticleDOI
Breakup of a liquid rivulet falling over an inclined plate: Identification of a critical Weber number
TL;DR: In this paper, the authors have numerically investigated the breakup of a rivulet falling over a smooth inclined plate using the volume of fluid method and the Kapitza number (Ka).
Journal Article
Simulation study of a hybrid process for the prevention of weld bead hump formation : A numerical simulation shows how formation of bead humps in high-speed GMAW is prevented by additional laser heat input
M. H. Cho,D. F. Farson +1 more
TL;DR: In this paper, a three-dimensional numerical simulation of heat and fluid flow and phase change in pulsed gas metal arc weld (GMAW-P) deposits was used to study hump formation and its suppression by a hybrid laser welding process.
Journal ArticleDOI
Capillary instabilities of liquid films inside a wedge
Li Yang,George M. Homsy +1 more
TL;DR: In this paper, a liquid meniscus inside a wedge of included angle 2β that wets the solid walls with a contact angle θ is considered, and the numerical results agree qualitatively with our results.
Journal ArticleDOI
Static rivulet instabilities: varicose and sinuous modes
Joshua Bostwick,Paul H. Steen +1 more
TL;DR: In this paper, the governing hydrodynamic equations for this inviscid, incompressible fluid are derived and then reduced to a functional eigenvalue problem on linear operators, which are parametrized by axial wavenumber and base-state volume.
Journal ArticleDOI
Tailoring Ink-Substrate Interactions via Thin Polymeric Layers for High-Resolution Printing
TL;DR: It is shown that the wetting of a substrate and, consequently, the quality of the printed pattern, can be mediated through the deposition of polymeric layers that are a few nanometers thick, which enables the inkjet printing of complex structures with a high resolution.
References
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Book
Methods of Mathematical Physics
Richard Courant,David Hilbert +1 more
TL;DR: In this paper, the authors present an algebraic extension of LINEAR TRANSFORMATIONS and QUADRATIC FORMS, and apply it to EIGEN-VARIATIONS.
Journal ArticleDOI
Methods of Mathematical Physics
TL;DR: In this paper, the authors present an algebraic extension of LINEAR TRANSFORMATIONS and QUADRATIC FORMS, and apply it to EIGEN-VARIATIONS.
Journal ArticleDOI
On the Spreading of Liquids on Solid Surfaces: Static and Dynamic Contact Lines
TL;DR: In this article, it is shown that the mutual interaction between the three materials in the immediate vicinity of a contact line can significantly affect the statics as well as the dynamics of an entire flow field.
Liquids on solid surfaces: static and dynamic contact lines
TL;DR: In this paper, it is shown that the mutual interaction between the three materials in the immediate vicinity of a contact line can significantly affect the statics as well as the dynamics of an entire flow field.