Multiple high-fidelity, time-accurate computational fluid dynamics simulations were performed to investigate the effects of upstream stator loading and rotor shock strength on vortex shedding characteristics in a single stage transonic compressor. Various configurations of a transonic axial compressor stage, including three stator/rotor axial spacings of close, mid, and far in conjunction with three stator loadings of decreased, nominal, and increased were simulated in order to understand the flow physics of transonic blade-row interactions. Low-speed compressors typically have reduced stator/rotor axial spacing in order to decrease engine weight, and also because there is an increase in efficiency with reduced axial spacing. The presence of a rotor bow shock in high-speed compressors causes additional losses as the shock interacts with the upstream stator trailing edge. This research analyzes the strength of shock-induced vortices due to these unsteady blade-row interactions. The time-accurate URANS code, TURBO, was used to generate periodic, quarter annulus simulations of the Blade Row Interaction compressor rig. Both time-averaged and time-accurate results compare well with experimentally-observed trends. It was observed that vortex shedding was synchronized to the passing of a rotor bow shock. Normal and large shock-induced vortices formed on the stator trailing edge immediately after the shock passing, but the large vortices were strengthened at the trailing edge due to a low-velocity region on the suction surface. This low velocity region was generated upstream of mid-chord on the suction surface from a shock-induced thickening of the boundary layer or separation bubble, due to the rotor bow shock reflecting off the stator trailing edge and propagating upstream. The circulation of the shock-induced vortices increased with shock strength (decreased axial spacing) and stator loading. Most design tools do not directly account for unsteady effects such as blade-row interactions, so a model is developed to help designers account for shock-induced vortex strength with varying shock strength and stator loading. An understanding of the unsteady interactions associated with blade loading and rotor shock strength in transonic stages will help compressor designers account for unsteady flow physics early in the design process.

High fidelity measurements are necessary to validate existing and future turbulence models for the purpose of producing the next generation of more efficient gas turbines. The objective of the present study is to conduct several different measurements of multi-row film cooling arrays in order to better understand the physics involved with injection of coolant through multiple rows of discrete holes into a flat plate turbulent boundary layer. Adiabatic effectiveness distributions are measured for several multi-row film cooling geometries. The geometries are designed with two different hole spacings and two different hole types to yield four total geometries. One of the four geometries tested for adiabatic effectiveness was selected for flowfield measurements. The wall and flowfield are studied with several testing techniques, including: particle image velocimetry, hot wire anemometry, pressure sensitive paint and discrete gas sampling.

The present work studies the relationship between target and sidewall surfaces of a multirow, narrow impingement channel at various jet heights with one impingement hole per row. Temperature sensitive paint and constant flux heaters are used to gather heat transfer data on the target and side walls. Jet-to-target distance is set to 1, 2, 3, 5, 7 and 9 jet diameters. The channel width is 4 jet diameters and the jet stream wise spacing is 5 jet diameters. All cases were run at Reynolds numbers ranging from 5,000 to 30,000. Pressure data is also gathered and used to calculate the channel mass flux profiles, used to better understand the flow characteristics of the impingement channel. While target plate heat transfer profiles have been thoroughly studied in the literature, side wall data has only recently begun to be studied. The present work shows the significant impact the side walls provide to the overall heat transfer capabilities of the impingement channel. It was shown that the side walls provide a significant amount of heat transfer to the channel. A channel height of three diameters was found to be the optimum height in order to achieve the largest heat transfer rates out of all channels.

<p> In Part I the one-electron charge distribution in the water molecule is obtained by demanding that this distribution balance the nuclear forces of repulsion and reproduce the observed dipole moment. Parameters contained in the molecular orbital description are then related to such concepts as hybridisation and bond polarities. </p> <p> In Part II the electronic forces of attraction and the one-electron charge distribution, calculated from near Hartree-Fock wave functions, are used to interpret the binding in the first-row diatomic hydrides. </p> / Thesis / Doctor of Philosophy (PhD)

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Great architecture exists by creating an equilibrium between the experiential world and the intellectual world. On one hand these two worlds operate at polar opposites, while on the other hand these two worlds are totally dependent on one another’s existence. Through the conscious pursuit of reconciling these differences, the creation process is open to its fullest realm of possibilities and complexities. Le Corbusier used the intellectual world to gain the experiential. Although, in his later years, this process began to reverse itself. Alvaro Siza uses the experiential world to gain the intellectual. While these processes are pursued from opposite extremes, the final works reach a common goal. That goal being a complete fusion of the experiential and intellectual worlds which allows these works to procure a vital new spirit. One other case needs to be mentioned here. This being the case of Alvar Aalto. Aalto was pure genius in his understanding the significance and consequences of unifying the experiential and intellectual worlds. As a result, I believe Aalto's starting point was where the reconciliation of these two worlds occurs. By starting at this point, Aalto allowed himself the enormous freedom of reaching out simultaneously to both the experiential and intellectual worlds, extracting whatever components were necessary to create his wonderful works of art. A major objective for me is to simultaneously reconcile the experiential and intellectual worlds into a harmonious equilibrium. The moment this harmonious equilibrium occurs is the point where architecture is on the threshold of beauty / Master of Architecture

In the past 30 years the size of new houses has varied considerably with a general trend to larger houses. These larger houses use more materials in their construction and consume more energy to heat and cool than a more compact house would. Meanwhile, the amount of resources that are available have not increased, and the environmental condition of the planet has become more and more tenuous. To end this trend of larger houses that make inefficient use of natural resources, architects need to design houses that are smaller and use energy more efficiently. By building houses more in tune with the natural rhythms of the sun and seasons the home becomes more energy efficient and can take better advantage of the natural energy supply available from the sun. Such a house will have less of an impact on the environment and keep the residents in touch with natural cycle of life. With this project I have addressed these issues and have designed a row of houses that provide a meaningful place to live that is also in tune with the environment. As with any project, I have found the answers to many questions and I have also discovered new ideas to develop further / Master of Architecture

This thesis explores an architectural housing solution for the middle income sector of the United States. The impetus for this exploration is founded in the conviction that housing must respond to the desires and needs of its occupants. An understanding of these desires and needs was discerned through studying the background of housing. Based on this background and current observations, clustering houses is an appropriate and necessary strategy for the middle-income sector. To investigate this strategy, a design was executed and used as a vehicle to explore the architecture of cluster housing. The success of this strategy and my opinions on issues raised in this design response are discussed. Neither this discussion, nor this thesis, is intended to be a definitive statement on housing. / Master of Architecture

The investigation of the Spirit of a historic place, Alexandria, Virginia to acquire an understanding of it’s identity; the unique patterns, language, structure, rhythm, and character, which has led to its development as a meaningful place. To respect the Spirit of this place through the design of a place to dwell within Alexandria which is sensitive to, and evolves from, this living tradition. An architecture which achieves meaning through its relation to, and reinterpretation, transformation, and revelation of the inherent qualities of the historic artifact. / Master of Architecture