DIT PhD Project
Supervisor name & contact details:
Dr Fergal Boyle
Email: fergal.boyle@dit.ie
Supervisors Profile:
Research Centre:
Dublin Energy Laboratory
The Dublin Energy Lab is a leading energy
related research and development laboratory
which conducts research across a range of
disciplines with key efforts organised into
themes of electrical power; energy policy; solar
energy; zero emissions buildings; energy
demand analysis and forecasting; life cycle
assessment.
Research Centre website:
www.dit.ie/dublinenergylab/
Supervisors Publications List:
http://arrow.dit.ie/do/search/?q=author_lnam
e%3A%22Boyle%22%20AND%20author_fname
%3A%22Fergal%22&sort=date_desc&fq=ancest
or_key:490738
Title of the Project: High Fidelity Numerical Modelling of Red-Blood-Cell
Structural Mechanics using a Dual-Layer Membrane Model
Project Summary: Red blood cells (RBCs) are the major formed elements in whole blood,
primarily responsible for the delivery of oxygen to the microcirculation where the exchange of
nutritional and waste products takes place. RBCs are biconcave in shape, typically with a
diameter of eight microns, a thickness of two microns, and a centre thickness of one micron;
however they can squeeze through capillaries in the microcirculation with a diameter of only
three microns. The impressive flexibility of RBCs is attributed to their unique but simple structural
organisation. Physically, an RBC is a capsule enclosing a haemoglobin cytoplasm commonly
considered as a Newtonian fluid. The capsule membrane has a dual-layer structure. The outer
layer is a continuum surface about five nanometres in depth. It is composed of a phospholipid
bilayer with small amounts of proteins and carbohydrates dispersed within its structure. The
constituents of the phospholipid bilayer are free to move in the layer, and the layer exhibits no
shear but has a high dilation force. The inner layer facing the cytoplasm, known as the
cytoskeleton, has a network topology and is observable in the region 100-300 nanometres
underneath the phospholipid bilayer. The cytoskeleton network is a multi-protein complex
composed mainly of spectrin strands and actin junction complexes. The two layers of the RBC
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membrane, the phospholipid bilayer and the cytoskeleton, are linked by proteins in each layer.
A significant amount of research has been conducted to-date into RBC structural mechanics,
especially in the last three decades. This can be attributed to interest in RBC rheology and, in
particular, to interest into blood-related-disease pathology. In vivo/vitro RBC experimentation is
very difficult due to the length scales involved and, hence, numerical simulation has become
increasingly popular for investigating RBC structural behaviour. Normally, numerical models
assume the RBC membrane is a uniform material with a zero thickness. This assumption
simplifies the numerical treatment of membrane mechanics, but it also leads to inaccuracies in
membrane properties however.
This project involves the development of a three-dimensional numerical model of an RBC for
structural analyses. Specifically the model will incorporate a dual-layer membrane model. It is
envisaged that the model will combine techniques for continuum mechanics (e.g. finite element
method) with discrete-based techniques (e.g. springs) for modelling the phospholipid bilayer and
the cytoskeleton network respectively, and will leverage the processing power of general
purpose graphical processing units (GPGPUs). It is anticipated that the developed model will be
the most realistic developed to-date, and will facilitate greater understanding of the pathology of
important blood-related diseases.
Ciência sem Fronteiras / Science Without Borders Priority Area
Engineering and other technological areas
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