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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Design and Development of an Apparatus to Study Aviation Jet Fuel Thermal Stability

Wong, Owen 30 December 2010 (has links)
A single tube flow heat exchanger was designed and built to thermally stress Jet A-1 with air-saturated and deoxygenated levels of dissolved oxygen over a range of fuel temperatures, pressures, and flow rates. Liquid samples of thermally degraded Jet A-1 were analyzed using various physical and optical methods to determine which methods were sensitive enough to measure compositional changes in thermally degraded liquid fuel and to correlate these changes to the measured amount of deposits produced. Temperature programmed oxidation (TPO) was shown to be successful in measuring deposit quantity and structure, while UV-visible absorption and UV-visible fluorescence were sensitive enough to quickly measure the relative population growth of large aromatic compounds that lead to deposit formation in thermally stressed Jet A-1.
142

The effect of synthetic jet driving parameters on heat transfer in microchips cooling channels

Li, Dan, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2009 (has links)
With the growing power dissipation and more densely packed circuits, the issue of efficient thermal management has become crucial. The safe and reliable operations of microchips have a requirement on a junction temperature below 85??C. In order to meet the heat dissipation requirement at the level of 1 MW m???? of the next generation microchips, a new cooling approach has been proposed by combining the merits from forced convection in the microchannel and the synthetic jet impingements. A parametric study has been carried out on the operating conditions on the synthetic jet actuator, these parameters including: the frequency of the diaphragm in the actuator, the jet outlet velocity both in magnitude and the wave shape as well as the pressure difference between the channel two ends. It was found that these parameters have combined effect on the flow structure as well as the heat transfer rate in the microchannel. When the average jet velocity was at 2.36 ms??¹(Rej= 130), with a fixed pressure difference at 750 Pa, the maximum temperature in the silicon wafer has been reduced to about 343 K at both 560 and 1120 Hz, which was 2 K lower than when 280 Hz was used. However when the average jet velocity was increased by 50 %, the optimal heat transfer then occurred at 1120 Hz, the maximum temperature was reduced to 337 K, with 4 K and 5K difference of 280 and 560 Hz, respectively. Furthermore when the average jet velocity was doubled from Rej= 130, the frequency at 280 Hz achieved the lowest maximum temperature in the wafer at 336 K that was 5 K and 3 K lower than 560 Hz and 1120 Hz. The flow temperature in the actuator is an important factor which affects the heat transfer in the microchannel. In order to lower the cavity temperature and avoid the ingestion of the already mixed flow, the time portion of the ingestion and ejection phases has been altered, by reducing the ejection time and increasing the ingestion time. However this approach did not show any significant effect in the heat transfer process or decreasing the flow temperature in the cavity. However in a later study by increasing the pressure difference across the channel, the flow temperature in the cavity has been substantially reduced and the heat transfer in the channel changed significantly according to the flow structure. It was found that the high pressure in the channel could deliver the vortical structure to the hotter part of the wafer thus decreasing the maximum temperature in the silicon effectively, especially when high jet velocity was used. When high jet velocity has been used, irregular variation of the flow was found The unrepeatable feature of the flow is related to the frequency, jet velocity as well as the channel pressure difference.
143

The enhanced mixing burner / submitted by Graham Jerrold Nathan for the Degree of Doctor of Philosophy

Nathan, Graham Jerrold, University of Adelaide. Dept. of Mechanical Engineering January 1988 (has links)
Cased / Bibliography: p. 210-219 / xx, 239 leaves : ill. (some col.) ; 30 cm. + 1 16mm film / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Mechanical Engineering, 1989
144

Analysis of intense sub-tropical moisture transports into high latitudes of western North America

Roberge, Alain. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Atmospheric and Oceanic Sciences. Title from title page of PDF (viewed 2008/07/30). Includes bibliographical references.
145

Parametric study of liquid fuel jet in crossflow at conditions typical of aerospace applications

Reichel, Jonathan R. January 2008 (has links)
Thesis (M. S.)--Aerospace Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Ben Zinn; Committee Member: Eugene Lubarsky; Committee Member: Jerry Seitzman.
146

Simulation of tri-axially braided composites half-cylinder behavior during balistic [sic] impact

Staniszewski, Marcin. January 2007 (has links)
Thesis (M.S.)--University of Akron, Dept. of Civil Engineering, 2007. / "May, 2007." Title from electronic thesis title page (viewed 4/28/2009) Advisor, Wieslaw K. Binienda; Committee members, Craig C. Menzemer, Ala Abbas; Department Chair, Wieslaw K. Binienda; Dean of the College, George K. Haritos; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
147

Nonlinear six degree of freedom simulation of a twin jet engine transport aircraft

Wozniak, Jason G. January 1997 (has links)
Thesis (M.S.)--Ohio University, August, 1997. / Title from PDF t.p.
148

Gloss development of spray-coated systems /

Clark, Aaron W., January 2004 (has links)
Thesis (M.S.) in Chemical Engineering--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 77-79).
149

Computational fluid dynamic model of steam ingestion into a transonic compressor

Hedges, Collin R. January 2009 (has links) (PDF)
Thesis (M.S. in Mechanical Engiineering)--Naval Postgraduate School, June 2009. / Thesis Advisor(s): Gannon, Anthony J. "June 2009." Author(s) subject terms: Computational Fluid Dynamics, Transonic, Compressor, Steam Ingestion, Sanger Rotor. Description based on title screen as viewed on July 10, 2009. Includes bibliographical references (p. 61). Also available in print.
150

A numerical investigation on the influence of engine shape and mixing processes on wave engine performance

Erickson, Robert R. January 2004 (has links) (PDF)
Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2005. / Ben T. Zinn, Committee Chair ; Jeff Jagoda, Committee Member ; Suresh Menon, Committee Member ; Tim Lieuwen, Committee Member ; Rick Gaeta, Committee Member. Vita. Includes bibliographical references.

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