Dr Ian Halliday

Ian_Halliday.jpg
Job title: 
Reader

Phone 0114 225 3045 
E-mail i.halliday@shu.ac.uk

Research interests

  • Lattice Boltzmann equation (lBe)
  • lBe for hydrodynamics
  • lBe nematodynamics
  • Multi—component lBe
  • Modelling of blood flow

Current activity

PhD supervision

I currently have three excellent Phd students - Mike Dupin (supported by fluent) and Rachael Law (supported by BNFL) and (writing-up) Lee Hammond (supported by Rolls Royce Associates).

Research

My research project involves modelling liquid crystalline fluids in a slab geometry in order to study the surface induced structural changes on the system. Several surface models ranging from simplistic to realistic are used and the anchoring transitions between the stable surface arrangements are studied. Specifically I am interested bistable anchoring. Flexoelectric particles with a shape anisotropy (pear shaped) are also used. The ultimate goal is to be able to model a thin display cell were switching between two states can be surface induced, using the combined effect of a bistable anchoring and the flexoelectric effect.

Project

I am currently working on lattice Boltzmann equation hydrodynamics. The essentially applied areas described under the heading “research interests” are all pretty active but I am also interested in a number of fundamental issues around lattice Boltzmann equation hydrodynamics and in particular around multi—phase lattice Boltzmann. In particular, high density contrast interfaces, stability and the link to classical kinetic theory and hydrodynamics.

I am involved in the following projects

  • Lattice Boltzmann Model
    Fundamantals viscous incompressible multi-component lattice Boltzmann (lB) fluid models. Here our primary concern is the essential method by which surface tension in the model is activated and regulated: specifically, the extent to which interfacial behaviour in lB fluids a) is hydrodynamic and b) may be adjusted (made isotropic, ranged etc.), are the primary focus of our activities [7,9]. Recent theoretical work on calculating (as opposed to mesuring) Laplace Law surface tension and on new algorithms capable of producing a more singular, isotropic interface are providing exciting results. Issues relating to application of the method (to e.g. the simulation of microemulsions) are also generating results [8]. This programme has recently (2001) undergone an expansion, with the advent of backing from market--leading CFD software supplier Fluent. The current programme should raise the profile of the method, especially in the emerging field of bio-medical applications.
  • Multi-component fluid flow
    We have very recently generalized the multi—component lattice Boltzmann equation algorithm to bring multiple immiscible species within the range of the method. This opens applications in internal complex flow at (possibly) very high volume fraction. By modelling deformable objects on mutually immiscible, relatively viscous drops, suspended in an ambient fluid several potential applications emerge: sludge flow and certain regimes of blood flow (veinule microcirculation) become accessible.
  • Engineering flows using Lattice Boltzmann
    We have very recently generalized the multi—component lattice Boltzmann equation algorithm to bring multiple immiscible species within the range of the method. This opens applications in internal complex flow at (possibly) very high volume fraction. By modelling deformable objects on mutually immiscible, relatively viscous drops, suspended in an ambient fluid several potential applications emerge: sludge flow and certain regimes of blood flow (veinule microcirculation) become accessible.

  • Nematodynamics
    By introducing an internal (orientational) degree of freedom into a minimalist model we have generated a “world— leading” derivative lB technique which provides access to mesosciopic length scales in comple fluids (nematics) which contain an interaction between the local flow and orientational order in the lattice fluid tuned to recover physically correct governing equations. Renewed funding has allowed technique to be applied to complex geometry of a seminal device.

 

Recent Publications 

All of Ian's papers can be accessed at SHURA.

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