Thesis (Ph.D.)--York University, 2005. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 113-120). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR11603

Thesis (M.S.)--University of Alabama at Birmingham, 2007. / Description based on contents viewed Feb. 4, 2008; title from title screen. Includes bibliographical references (p. 73-77).

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 172-183). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph.D.)--City University of Hong Kong, 2005. / "Submitted to Department of Mathematics in partial fulfillment of the requirements for the degree of Doctor of Philosophy" Includes bibliographical references (leaves 72-77)

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Mikhail M. Vishik. Vita. Includes bibliographical references.

Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xiii, 135 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 118-127).

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves [66]-68). Also available in electronic version.

This thesis concentrates on accuracy improvements for an existing software package that solves the three dimensional Reynolds Averaged Navier-Stokes equations in rotating coordinates. It is a cell centred explicit time marching code. Two topics are considered: improvement to the discretization scheme, and reduction of the artificial dissipation. The first topic is the analysis of the straight averaging process which demonstrates that the process can result in inconsistency with a skewed grid. An alternative consistent scheme is proposed which is based upon quadratic interpolation. Improved accuracy can also be obtained by modifying the grid or adopting a cell vertex scheme. The stability of the iterative process is also shown to depend on the time step. The reduction of artificial dissipation (second topic) first considers the role of the so called aspectratio and velocity functions. These are found to be limited in influence and a new function is proposed based upon the local flow gradient. Both two and three dimensional turbomachinery cases are tested and improvements demonstrated. In the second part of the analysis, the eigenvalues of the stability matrix are used to reduce the dissipation in overdamped regions. Again this method is applied to various test cases and improvements demonstrated. The management part of this Total Technology PhD Program discusses topics concerned with collaboration and technology development in the aero engine industry with particular emphasis on the role of an 'emerging' partner.

The marker and cell method is an efficient co-volume technique suitable for the solution of incompressible flows using a Cartesian mesh. For flows around complex geometries the use of an unstructured mesh is desirable. For geometric flexibility an unstructured mesh implementation is desirable. A co-volume technique requires a dual orthogonal mesh, in the triangular case the Delaunay-Voronoi dual provides the means for determining this dual orthogonal mesh in an unstructured mesh framework. Certain mesh criteria must be placed on the Delaunay-Voronoi to ensure it meets the dual orthogonal requirements. The two dimensional extension of the marker and cell method to an unstructured framework is presented. The requirements of the mesh are defined and methods in their production are discussed. Initially an explicit time stepping scheme is implemented which allows efficient simulation of incompressible fluid flow problems. Limitations of the explicit time stepping scheme that were discovered, mean that high Reynolds number flows that require the use of stretched meshes cannot produce solutions in a reasonable time period. A semi-implicit time stepping routine removes this limitation allowing these types of flows to be successfully modelled. To validate the solvers accuracy and demonstrate its performance, a number of test cases are presented. These include the lid driven cavity, flow over a backward facing step, inviscid flow around a circular cylinder, unsteady flow around a circular cylinder, flow around an SD7003 aerofoil, flow around a NACA0012 aerofoil and flow around a multi element aerofoil. The investigation although revealing a high dependence on the quality of the mesh still demonstrates that accurate results can be obtained efficiently. The efficiency is demonstrated by comparison to the in-house 2D incompressible finite volume solver for flow around a circular cylinder. For this case the unstructured MAC method produced a solution four times faster than the finite volume code.

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