Modelling and Simulation of High-viscosity, Non Iso-thermal Fluids with a Free Surface

A combined numerical and experimental investigation of coalescence of droplets of highly viscous liquids dropped on a surface has been carried out. Droplets of 87 wt% glycerin-in-water solutions with viscosity 110 centistokes were deposited sequentially in straight lines onto a flat, solid steel plate and droplet impact photographed. Impacting droplets spread on the surface until liquid surface tension and viscosity overcame inertial forces and the droplets recoiled, eventually reaching equilibrium. Droplet center-to-center distance was varied and droplet line length was measured from photographs. As droplet spacing was increased there was less interaction between the droplets. A three dimensional parallel code has been developed to simulate fluid flow and free surface interaction by solving the continuity, momentum and volume-of-fluid (VOF) equations. The two-step projection method was employed to solve the governing equations for the whole domain including both liquid and air phases. The continuum-surface-force (CSF) scheme was applied to model surface tension and the piecewise-linear-interface-construction (PLIC) technique used to reconstruct the free surface. Computer generated images of impacting droplets modeled droplet shape evolution correctly and compared well with photographs taken during experiments. Accurate predictions were obtained for droplet line length during spreading and at equilibrium.

Download Full-text

Flow regimes of a high-viscosity polymer mass bounded by the free surface in the region of drastic expansion of a channel

Journal of Applied Mechanics and Technical Physics ◽

10.1007/s10808-008-0009-3 ◽

2008 ◽

Vol 49 (1) ◽

pp. 64-70

Author(s):

A. N. Kozloborodov ◽

G. R. Shrager

Keyword(s):

Free Surface ◽

Flow Regimes ◽

High Viscosity ◽

Viscosity Polymer

Download Full-text

Simulation of Solid-Liquid Interaction in Presence of a Free Surface

ASME-JSME-KSME 2011 Joint Fluids Engineering Conference: Volume 1, Symposia – Parts A, B, C, and D ◽

10.1115/ajk2011-09019 ◽

2011 ◽

Cited By ~ 1

Author(s):

Iman Mirzaii ◽

Mohammad Passandideh-Fard

Keyword(s):

Free Surface ◽

Rigid Motion ◽

Free Fall ◽

Free Surface Flow ◽

High Viscosity ◽

Surface Flow ◽

Computational Domain ◽

Solid Object ◽

Solid Liquid Interface ◽

Solid Liquid

In this study, a numerical algorithm is developed for simulating the interactions between a liquid and solid object in presence of a free-surface flow. The presented model is that of the fast-fictitious-domain method integrated into the volume-of-fluid (VOF) technique used for tracking the free surface motion. The developed model considers the solid object as a fluid with a high viscosity resulting in a rigid motion of the object and solves the governing equations everywhere in the computational domain including the solid object. In this methodology, the application of the no-slip condition on the solid-liquid interface and the evaluation of the acting forces on the solid object are performed implicitly. The developed model is validated by a comparison of the simulation results with those of the available experiments in the literature for the free fall of one and two circular disks in a liquid domain and a sphere during its entry into a more dense liquid through a free surface. For all cases considered, the results are in good agreement with those of the experiments and other numerical studies. The model is then used to simulate the complex liquid-solid interaction during the entry of a spinning disk into a liquid free surface.

Download Full-text

Modelling and Simulation of the Three-Dimensional Hydrodynamic Problem

Thermal Hydraulic Problems, Sloshing Phenomena, and Extreme Loads on Structures ◽

10.1115/pvp2002-1142 ◽

2002 ◽

Author(s):

Matthieu Tourbier ◽

Bernard Peseux ◽

Bundi Donguy ◽

Laurent Gornet

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Free Surface ◽

Variational Formulation ◽

Three Dimensional ◽

Rigid Bodies ◽

Modelling And Simulation ◽

Hydrodynamic Problem ◽

Plastic Deformations ◽

Deformable Structure

This paper deals with slamming phenomenon (impact between bow ship and water free surface). Slamming loads on ship may be sufficiently important so as to create plastic deformations of the hull external structure. In extreme cases, they have been recognised for being responsible for the loss of ships. The problem to solve is transient and highly non-linear due to the character of the flow. In the present paper, the three-dimensional Wagner problem is solved numerically using a variational formulation together with a Finite Element Method. Three-dimensional results for simple rigid bodies such as a cone and an ellipsoid are successfully compared with analytical results. Results for deformable structure will be presented.

Download Full-text

Development of a Lagrangian-Lagrangian Coupling Method in Solid-Liquid Flows Involving Free Surface

ASME-JSME-KSME 2011 Joint Fluids Engineering Conference: Volume 1, Symposia – Parts A, B, C, and D ◽

10.1115/ajk2011-09016 ◽

2011 ◽

Author(s):

Y. Yamada ◽

M. Sakai ◽

S. Mizutani ◽

S. Koshizuka ◽

T. Nonoue ◽

...

Keyword(s):

Free Surface ◽

Numerical Simulations ◽

Multiphase Flows ◽

Industrial Area ◽

High Viscosity ◽

Coupling Method ◽

Complex Flows ◽

Numerical Studies ◽

Liquid Flows ◽

Solid Liquid

In the industrial area, handling solid-liquid multiphase flows involving free surface is one of the most important problems. However, numerical studies on these complex flows have not been done so far. In this study, we develop a new method to simulate the solid-liquid flows with high viscosity. Lagrangian approaches were employed in the liquid and solid coupling method. Numerical simulations were performed to show the adequacy of this model.

Download Full-text

On the role of tin underlays for the prevention of thermal grooving in thin gold films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145030 ◽

1986 ◽

Vol 44 ◽

pp. 732-733

Author(s):

Jin Young Kim ◽

R. E. Hummel ◽

R. T. DeHoff

Keyword(s):

Thin Film ◽

Free Surface ◽

Grain Boundary ◽

Beneficial Effect ◽

Failure Mechanism ◽

Failure Mechanisms ◽

Distinct Advantage ◽

Gold Films ◽

Gold Thin Film

Gold thin film metallizations in microelectronic circuits have a distinct advantage over those consisting of aluminum because they are less susceptible to electromigration. When electromigration is no longer the principal failure mechanism, other failure mechanisms caused by d.c. stressing might become important. In gold thin-film metallizations, grain boundary grooving is the principal failure mechanism.Previous studies have shown that grain boundary grooving in gold films can be prevented by an indium underlay between the substrate and gold. The beneficial effect of the In/Au composite film is mainly due to roughening of the surface of the gold films, redistribution of indium on the gold films and formation of In2O3 on the free surface and along the grain boundaries of the gold films during air annealing.

Download Full-text