A one-dimensional model for wave-induced ice-floe collisions

In this study, the collision of ice floes under the action of a monotonic wave is quantified. The lateral motion of an ice floe caused by the wave is modeled as the sliding of an object under gravity. In this case, the gravity component in the direction of motion varies with time and space as the wave progresses by the floe. Drag and added mass effects are included in the model. Two floes located at different positions are shown to have a net difference in their drift (caused only be repeated wave passages). In most cases, this differential drift eventually causes floe collision. When two floes collide, a spring and dash-pot model is adopted to calculate the contact force. A one-dimensional wave passing through a one-dimensional array of disc-shaped floes is examined. Two phenomena are apparent from the analysis. First, waves have a herding effect that forms bands of floes with the width equal to the wavelength. Secondly, the frequency of collision is sensitive to the elastic properties of the floes and the wave amplitude. With sufficient values of the damping constant, which operates when two floes collide, the floes stay in contact for prolonged periods, indicating the potential to freeze together and form composite floes, as was observed in the field studies.

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Numerical Experiments Analysis of Wave-Induced Vertical Mixing’s Effects on Sea Surface Wind-Induced Momentum Transfer

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 4 ◽

10.1115/omae2010-20739 ◽

2010 ◽

Author(s):

Bingchen Liang ◽

Ying Liu ◽

Lili Yang

Keyword(s):

Fresh Water ◽

Yellow River ◽

Vertical Section ◽

Vertical Mixing ◽

Three Dimensional ◽

Velocity Profiles ◽

Dimensional Model ◽

One Dimensional ◽

Wave Induced ◽

Sediment Model

A hydrodynamic sediment coupled model COHERENS-SED, which has been developed by the present authors through introducing wave-enhanced bottom stress, wave dependent surface drag coefficient, wave-induced surface mixing, SWAN, damping function of sediment on turbulence and sediment model to COHERENS, is modified to account for wave-induced vertical mixing. One equation k–ε turbulence model is taken into account in calculating vertical viscosity coefficient. COHERENS-SED consists of sediment model SED, current model COHERENS and wave generation model SWAN. The model can also calculate one-dimensional, two-dimensional and three-dimensional current separately. One-dimensional model and three-dimensional model are adoptted to study the wave-induced vertical mixing’s effects. The horizontal current velocity profiles given by the model, with same input conditions as what to get analytical results, are in nice agreement with analytical velocity profiles. Therefore the model can be reliable to identify wave-induced vertical mixing’s effects on horizontal velocity profiles and momentum transferring. Two group numerical experiments are built based on 130m water depth and 20m water depth for the one-dimensional model. Results show that higher wave height can generate larger vertical eddy viscosity and lower horizontal velocity generally. In order to find out such effects on fresh water flume momentum transfer towards down in vertical section of estuary, Yellow River delta is chosen to study the effects of wave-induced vertical diffusion on sediment vertical mixing and the Yellow River estuary vertical cross-section is chosen to study fresh water disperse range in vertical section. The results of fresh water shows that wave-induced vertical mixing increases the momentum of fresh water transferring ability towards down to seabed. So fresh water flume length is compressed obviously.

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One-Dimensional Model for the Combined Heat Transfer in Open-Cell Metal Foam

Proceeding of Thermal Sciences 2004. Proceedings of the ASME - ZSIS International Thermal Science Seminar II ◽

10.1615/ichmt.2004.intthermscisemin.160 ◽

2004 ◽

Author(s):

Nihad Dukhan ◽

Pablo D. Quinones ◽

Carolina Briano ◽

Jessica Fontanez

Keyword(s):

Heat Transfer ◽

Metal Foam ◽

Dimensional Model ◽

Open Cell ◽

One Dimensional ◽

Combined Heat Transfer

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A TRANSIENT ONE-DIMENSIONAL MODEL OF MIXING AND SEGREGATION OF LIQUIDS IN PIPES

Multiphase Science and Technology ◽

10.1615/multscientechn.v22.i2.50 ◽

2010 ◽

Vol 22 (2) ◽

pp. 177-196

Author(s):

R. I. Issa ◽

A. Tomasello

Keyword(s):

Dimensional Model ◽

One Dimensional

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Modelling Techniques in Applied Glaciology: Numerical Modelling of Avalanches

Annals of Glaciology ◽

10.3189/s026030550000567x ◽

1983 ◽

Vol 4 ◽

pp. 297-297

Author(s):

G. Brugnot

Keyword(s):

Finite Difference Method ◽

Transverse Velocity ◽

Longitudinal Velocity ◽

Momentum Conservation ◽

Dimensional Model ◽

One Dimensional ◽

Modelling Techniques ◽

Reference Grid ◽

The One ◽

Near Future

We consider the paper by Brugnot and Pochat (1981), which describes a one-dimensional model applied to a snow avalanche. The main advance made here is the introduction of the second dimension in the runout zone. Indeed, in the channelled course, we still use the one-dimensional model, but, when the avalanche spreads before stopping, we apply a (x, y) grid on the ground and six equations have to be solved: (1) for the avalanche body, one equation for continuity and two equations for momentum conservation, and (2) at the front, one equation for continuity and two equations for momentum conservation. We suppose the front to be a mobile jump, with longitudinal velocity varying more rapidly than transverse velocity.We solve these equations by a finite difference method. This involves many topological problems, due to the actual position of the front, which is defined by its intersection with the reference grid (SI, YJ). In the near future our two directions of research will be testing the code on actual avalanches and improving it by trying to make it cheaper without impairing its accuracy.

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