Friday, March 29, 2013

Isogeometric analysis of large deformation of a cylinder shell. Done in jem/jive C++ code. Visualization done in Paraview.

Friday, March 22, 2013

Isogeometric Analysis of a cantilever beam with large displacement and rotation. Performed with MIGFEM--an IGA FEM code that is free for download at https://sourceforge.net/projects/cmcodes/

Thursday, March 21, 2013

SIAM National Student Chapter Conference 2013




Subject: SIAM National Student Chapter Conference 2013

A reminder that Registration is now open for participation in the annual SIAM National Student Chapter Conference to take place in Warwick on the 10th of May 2013:
 
 
The abstracts for the invited lectures are already available there and look really interesting!!
 

Plenary Talks:

Sponsor Talks:

 
 
The deadline for submission of a title/abstract for a short talk (20min) or a poster is 19 April.  

Tuesday, March 19, 2013

Applied Maths/Engineering Seminar - TODAY

Seminar today - Tuesday 19th March 2013 at 16:10 in M/2.06 (MATHS)

Speaker: Prof Serafim Kalliadasis (Imperial).

Title: Recent progress on the moving contact line problem.

Abstract: The moving contact line problem is a long-standing and fundamental challenge in the field of fluid dynamics, occurring when one fluid replaces another as it moves along a solid surface. Moving contact lines occur in a vast range of applications, where an apparent paradox of motion of a fluid-fluid interface, yet static fluid velocity at the solid satisfying the no-slip boundary condition arises. In this talk we will review recent progress on the problem made by our group.

The motion of a contact line is examined, and comparisons drawn, for a variety of proposed models in the literature. We first scrutinise a number of models in the classic test-bed system of spreading of a thin two-dimensional droplet on a planar substrate, showing that slip, precursor film and interface formation models effectively reduce to the same spreading behaviour. This latter model, developed by Shikhmurzaev a few years ago, is a complex and somewhat controversial one, differentiating itself by accounting for a variation in surface layer quantities and having finite-time surface tension relaxation. Extensions to consider substrate heterogeneities in this prototype system for slip models are also considered, such as for surface roughness and fluctuations in wetting properties through chemical variability. Analysis of a solid-liquid-gas diffuse-interface model is then presented, with no-slip at the solid and where the fluid phase is specified by a continuous density field. We first obtain a wetting boundary condition on the solid that allows us to consider the motion without any additional physics, i.e. without density gradients at the wall away from the contact line associated with precursor films.

Careful examination of the asymptotic behaviour as the contact line is approached is then shown to resolve the singularities associated with the moving contact line problem. Various features of the model are scrutinised alongside extensions to incorporate slip, finite-time relaxation of the chemical potential, or a precursor film at the wall. But these are not necessary to resolve the moving contact line problem.

Tea/coffee will be available in the UCAS Room afterwards


Tuesday, March 5, 2013

Applied Maths/Engineering Workshop - TODAY



Subject: Applied Maths/Engineering Workshop - TODAY

Tuesday 5th March

16:10 Applied Mathematics/Engineering Research Workshop: Room M/2.06

Speaker: Maurice Blount (MATHS)
Title: The adhesion and desiccation of a sessile vesicle

Abstract:
Anhydrobiosis is a proposed method of preserving biological material through drying it rather than freezing it.  To understand aspects of this process, I model the cell as a semi-permeable elastic membrane (a vesicle), and first apply a long-wave approximation to describe the drying process in regimes where the vesicle is strongly adhered to a substrate.  The results of this simplified model are compared with those of boundary-integral simulations, and I analyse the latter to show how the process of vesicle adhesion depends strongly on the thin layer of fluid that is trapped between the vesicle and the substrate.