dc.contributor.advisor |
Bradley, CP |
en |
dc.contributor.advisor |
Hunter, PJ |
en |
dc.contributor.author |
Ladd, David |
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dc.date.accessioned |
2017-01-24T20:03:02Z |
en |
dc.date.issued |
2016 |
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dc.identifier.uri |
http://hdl.handle.net/2292/31659 |
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dc.description.abstract |
As computing advances have made computational fluid dynamics (CFD) models of the vasculature more tractable, their corresponding adoption into clinical applications has not been equally forthcoming. Among the challenges limiting applicability are the lack of a consistent framework for the inherently multiscale problems encountered and the difficulties associated with accurately constraining models of vascular dynamics. The aim of this thesis is to develop models, methods, and tools that address aspects of both of these issues. With the recent developments in phase-contrast MRI velocimetry (PCV), clinical imaging can non-invasively measure fluid velocity in addition to geometry. In this thesis, novel methods are developed to t discontinuous in-vivo velocity measurements to continuous fields on computational domains. Fitting methods incorporate temporal spline interpolation and spatial inverse distance weighting (IDW), producing accurate velocity fields at nodal positions, independent of mesh size. Further findings suggest that the fitted velocity field data may also be used to directly estimate wall shear stress-based vascular disease indicators, which previously have only been reliably attainable with full CFD models. Open source computational models in this thesis are developed in the context of the VPH/Physiome project, which defines standards to facilitate interchange, documentation, and archival of complex models across physiological systems and scales. A residual-based variational multiscale (RBVM) model is developed for 2D and 3D CFD applications in the OpenCMISS library. A 1D formulation is also developed in OpenCMISS, allowing for rapid solution of ow and pressure over networks of distensible arteries. Coupled models that incorporate terminal vascular impedance and rheological constitutive relationships are encoded in the CellML standard, establishing a standards-based approach with "plug and play" ease of use. Multiscale approaches using these models are applied to physiologically relevant problems, including ow through a 1D systemic arterial tree, an iliac bifurcation, and an aortic aneurysm. These applications combine fitted PCV data, 3D CFD, and standards-based multiscale modelling. Results from the aortic aneurysm case also further supports the wall shear stress parameter estimation method using fitted PCV data. |
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dc.publisher |
ResearchSpace@Auckland |
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dc.relation.ispartof |
PhD Thesis - University of Auckland |
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dc.relation.isreferencedby |
UoA99264934811102091 |
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dc.rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. |
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dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
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dc.rights.uri |
http://creativecommons.org/licenses/by-nc-sa/3.0/nz/ |
en |
dc.title |
An open-source vascular modelling framework: from imaging to multiscale CFD |
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dc.type |
Thesis |
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thesis.degree.discipline |
Bioengineering |
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thesis.degree.grantor |
The University of Auckland |
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thesis.degree.level |
Doctoral |
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thesis.degree.name |
PhD |
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dc.rights.holder |
Copyright: The author |
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dc.rights.accessrights |
http://purl.org/eprint/accessRights/OpenAccess |
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pubs.elements-id |
609439 |
en |
pubs.org-id |
Bioengineering Institute |
en |
pubs.org-id |
ABI Associates |
en |
pubs.org-id |
Science |
en |
pubs.org-id |
Science Research |
en |
pubs.org-id |
Maurice Wilkins Centre (2010-2014) |
en |
pubs.record-created-at-source-date |
2017-01-25 |
en |
dc.identifier.wikidata |
Q112931175 |
|