Autumn 2016 Seminars and Abstracts Autumn 2016 Seminars and Abstracts

Unsteady Free-Surface Flow Cased by a Moving Circular Cylinder

Date: Monday 24th October, 3pm, (SCI 3.05)
Speaker: Dr Vasil Kostikov (Novosibirsk State University, Russia)
Abstract: A problem on non-stationary free surface flow of an infinitely deep ideal fluid generated due to the motion of a submerged body is considered. The initial formulation of the problem is reduced to an integral-differential system of equations for the functions defining the free surface shape, the normal and tangential components of velocity on the free boundary. Small- time asymptotic solution is constructed for the case of circular cylinder that moves with a constant acceleration from rest. The role of non-linearity is clarified by the analysis of this solution in the context of formation mechanism of added mass layers, splash jets and finite amplitude surface waves.

Modulation Instability of Finite Amplitude Periodic Travelling Waves: Theme and Variations

Date: Monday 14th November, 2pm, (LT4)
Speaker: Prof. Tom Bridges (University of Surrey)
Abstract: To be advised

To Be Advised

Date: Monday 21st November, 2pm, (SCI 1.20)
Speaker: Dr Jason Laurie (Aston University)
Abstract: To be advised

Variational Modelling of Water Waves and Their Impact on Moving Ships

Date: Monday 28th November, 2pm, (EFRY 1.01)
Speaker: Dr Anna Kalogirou (University of Leeds)
Abstract: The study of water waves has been an important area of research for years; their significance becomes obvious when looking at ocean and offshore engineering or naval architecture. Local weather and sea conditions can often lead to extreme wave phenomena, e.g. waves with irregular height. Waves with anomalously high amplitudes relative to the ambient waves are called rogue waves and can appear either at the coast or in the open ocean. The aim of this study is to investigate mathematically the generation and interaction of such waves and their impact on wave-energy devices and moving ships. The modelling is demonstrated by analysing variational methods asymptotically and numerically.

A reduced potential flow water-wave model is derived, based on the assumptions of waves with small amplitude and large wavelength. This model consists of a set of modified Benney-Luke equations describing the deviation from the still water surface and the velocity potential at the bottom of the domain. A novel feature in our model is that the dynamics are non-autonomous due to the explicit dependence of the equations on time. Numerical results obtained using a (dis)continuous Galerkin finite element method

(DGFEM) are compared to a soliton splash experiment in a long water channel with a contraction at its end, resulting after a sluice gate is removed at a finite time. The removal of the sluice gate is included in the variational principle through a time-dependent gravitational potential.

The Benney-Luke approximation for water waves is also adapted to accommodate nonlinear ship dynamics. The new model consists of the classical water-wave equations, coupled to a set of equations describing the dynamics of the ship. We will first investigate the dynamics of the coupled system linearised around a rest state. For simplicity, we also consider a simple ship structure consisting of V-shaped cross-sections. The model is solved numerically using a DGFEM and the numerical results are compared to observations from experiments in wave tanks that employ geometric wave amplification to create nonlinear rogue-wave effects.

Shock Waves in Non-Convex Dispersive Hydrodynamics

Date: Monday 12th January, 2pm, (LT3)
Speaker: Dr Gennady El (Loughborough University)
Abstract: To be advised

To Be Advised

Date: Monday 16th January, 2pm, (TBA)
Speaker: Dr Eric Lauga (University of Cambridge)
Abstract: To be advised

To Be Advised

Date: Monday 6th February, 2pm, (TBA)
Speaker: Dr Matthew Turner (University of Surrey)
Abstract: To be advised

To Be Advised

Date: Monday 6th March, 2pm, (TBA)
Speaker: Prof. Daniele Faccio (Heriot-Watt University)
Abstract: To be advised

To Be Advised

Date: Monday 20th March, 2pm, (TBA)
Speaker: Dr Konstantin Ilin (University of York)
Abstract: To be advised


For further details about the seminars, or to join our mailing list, please contact Davide Proment. For details of previous talks, please use the menu links on the left.