Thesis (Ph. D.)--Mississippi State University. Department of Computational Engineering. / Title from title screen. Includes bibliographical references.

Thesis--Auburn University, 2009. / Abstract. Includes bibliographic references (p.70-72).

Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 23, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Anthony R. Lupo. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (p. 219-228).

Thesis (Ph. D.) York University, 2001. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 222-227). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ67894.

Thesis (M.S. in Physical Oceanography)--Naval Postgraduate School, June 2003. / Thesis advisor(s): Timothy P. Stanton, Edward B. Thornton. Includes bibliographical references (p. 77-79). Also available online.

low about a periodic array of quasi-random distributed roughness is examined using an immersed boundary spectral method. Verification of the code used in the simulations is obtained by comparing solutions to LDA wake survey and flow visualization experiments for a periodic array of cylinders at a roughness height-based Reynolds number of 202 and a diameter to spanwise spacing d/[lambda] of 1/3. Direct comparisons for the quasi-random distributed roughness are made with experiments at roughness height-based Reynolds numbers of 164, 227, and 301. Near-field details are investigated to explore their effects upon transition. Vortices formed as the flow moves over the roughness patch create three distinct velocity deficit regions which persist far downstream. Simulated streamwise velocity contours show good agreement with experiments. Additional geometries are simulated to determine the effects of individual components of the full roughness geometry on near-field flow structures. It was found that the tallest regions of roughness determine the overall wake profile. / text

The proper scaling and prediction of the streamwise Reynolds stress in turbulent boundary layers has been a controversial issue for more than a decade as its Reynolds Number dependence can not be removed by normal scaling. One issue that may explain the unusual behavior of the streamwise Reynolds stress is that it is affected by both active and inactive motions per the Townsend hypothesis. The goal of this research is to develop a composite expansion for the streamwise Reynolds stress in turbulent boundary layers that considers active and inactive motions, explains various Reynolds Number dependencies, and agrees with available data. Data for the Reynolds shear stress and the streamwise Reynolds stress from six sources are evaluated and as appropriate plotted on inner and outer scales. A new asymptotic representation for the Reynolds shear stress, <uv>+, that meets the requirements for a proper composite expansion is developed and applied. This new Reynolds shear stress composite expansion agrees with data and allows predictions of <uv>+ for any Reynolds Number. The streamwise Reynolds stress, <uu>+, can be separated into active and inactive parts and the Reynolds shear stress can be used to represent the active part. The inactive streamwise Reynolds stress, <uIuI>#, is separated from the complete <uu>+ in part of this work. An outer correlation equation with the correct asymptotic limits for the inactive streamwise Reynolds stress is developed and shown to fit the outer part of the <uIuI># data. A separate inner correlation equation for inner inactive streamwise Reynolds stress is developed and fit to data. Together these two equations form a composite expansion for the inactive streamwise Reynolds stress for flat plate boundary layers. This composite expansion for the inactive streamwise Reynolds stress can be combined with the Reynolds shear stress expansion to produce predictions for <uu>+ that agree with data. Thus a composite expansion for predicting the streamwise Reynolds stress in turbulent boundary layers is developed and shown to reproduce the correct trends, to agree with the available data, and to explain the Reynolds Number dependence of the streamwise Reynolds stress. / text

A three dimensional viscous/inviscid interactive boundary layer method for predicting the effects of fluid viscosity on the performance of fully wetted propellers is presented. This method is developed by coupling a three dimensional low-order potential based panel method and a two dimensional integral boundary layer analysis method. To simplify the solution procedures, this method applies a reasonable assumption that the effects of the boundary layer along the span wise direction (radially outward for propeller blades) could be negligible compared with those along the stream wise direction (constant radius for propeller blades). One significant development of this method, compared with previous work, is to completely consider the effects of the added sources on the whole blades and wakes rather than evaluate the boundary layer effects along each strip, without interaction among strips. This method is applied to Propeller DTMB4119, Propeller NSRDC4381 and DTMB Duct II for validation. The results show good correlation with experimental measurements or RANS (ANSYS/FLUENT) results. The method is further used to develop a viscous image model for the cases of three dimensional wing blades between two parallel slip walls. An improved method for hydrofoils and propeller blades with non-zero thickness or open trailing edges is presented as well. The method in this thesis follows the idea of Pan (2009, 2011), but applies a new extension scheme, which uses second order polynomials to describe the extension edges. A improved simplified search scheme is also used to find the correct shape of the extension automatically to ensure the two conditions are satisfied. / text

A two-dimensional viscous-inviscid interactive boundary layer method is applied to three dimensional problems of flow around ducts and ducted propellers. The idea is to predict the effects of fluid viscosity on three dimensional geometries, like ducts, using a two-dimensional boundary layer solver to avoid solving the fully three dimensional boundary layer equations, assuming that the flow is two-dimensional on individual sections of the geometry. The viscous-inviscid interactive method couples a perturbation potential based inviscid panel method with a two-dimensional viscous boundary layer solver using the wall transpiration model. The boundary layer solver used in the study solves for the integral boundary layer characteristics given the edge velocity distribution on the geometry. The viscous-inviscid coupling is applied in a stripwise manner but by including the interaction e ffects from other strips. An important development in this thesis is the consideration of eff ects of other strips in a more rational and accurate manner, leading to improved results in the cases examined when compared to the results of a previous method. In particular, the effects of potentials due to other strips arising out of the three dimensional formulation are considered in this thesis. The validity of assuming two-dimensional flow along individual sections for application of viscous-inviscid coupling is investigated for the case of an open propeller by calculating the boundary layer characteristics in the direction normal to the assumed direction of two-dimensional flow from data obtained by RANS simulations. Also, a previous method which models the flow around the trailing edge of blunt hydrofoils has been improved and extended to three dimensional axisymmetric ducts. This method is applied to ducts with blunt and sharp trailing edges and to a ducted propeller. Correlations of results with experiments and simulations from RANS are shown. / text