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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.
581

Manning and automation of naval surface combatants : a functional allocation approach using axiomatic design theory

Szatkowski, John J. (John Joseph), 1967- January 2000 (has links)
Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000. / Includes bibliographical references (p. 431-432). / The design of ships is an inherently complex process. This complexity is significantly increased when the particular ship being designed is a naval surface combatant. The ship design process is traditionally viewed as a highly coupled collection of interrelated physical attributes often determined in an ad hoc fashion. Therefore, lack of understanding and documenting the design progression frequently necessitates modification of a completely developed, functionally acceptable portion of the ship because of its undesirable effect on other functionally unrelated parameters. A methodology based on axiomatic design principles that strives to eliminate the currently accepted iterative nature of concept level ship design is proposed. Specifically, the hierarchical decomposition of a naval surface combatant based on functional requirements mapped into physical design parameters reveals physical couplings. Studying the design at each level of the hierarchy determines the logical order to fulfill each requirement such that these couplings do not adversely impact the design progression. By implementing this methodical approach, the ship design process follows a repeatable structured format in which functional relationships between physical parameters are mapped, documented, and controlled. Since functional design is the key to this methodology, it is extended to assist designers with assigning tasks between shipboard personnel and automated machines. With this proposed approach, functional allocation is not only possible, but also the overall ship effect of each manning and automation decision is readily determined. A case study demonstrating this point is presented. / by John J. Szatkowski. / S.M. / Nav.E.
582

Diesel injection of coal-water slurry

Close, Timothy Mark January 1986 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, and (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1986. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 66-67. / by Timothy Mark Close. / M.S.
583

Analytical crashworthiness methods applied to composite structures

Lehnhardt, Keith W. (Keith William), 1967- January 1999 (has links)
Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999. / Includes bibliographical references (leaves 57-58). / by Keith W. Lehnhardt. / S.M. / Nav.E.
584

Acoustic transmission through fluid-filled pipes in boreholes

Rama Rao, V. N January 1991 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1991, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1991. / by Rama Rao V.N. / M.S.
585

A time marching boundary element method for the prediction of the flow around surface piercing hydrofoils

Savineau, Cedric Marcel January 1996 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1996, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1995. / Includes bibliographical references (leaf 68). / by Cedric Marcel Savineau. / M.S.
586

The effect of vibration mount aging on machinery raft displacement and vibration isolation performance

Lavallée, Jean G., 1960- January 2000 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000. / Includes bibliographical references (p. 76). / by Jean G. Lavallée. / S.M.
587

A comparison of experimental and computational analyses of two dimensional foil sections

Fairman, Randall S. (Randall Scott), 1967- January 2000 (has links)
Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000. / Includes bibliographical references (leaves 48-49). / by Randall S. Fairman. / Nav.E. / S.M.
588

Analysis and design of developable surfaces for shipbuilding

Chalfant, Julie Steele January 1997 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1997, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1997. / Includes bibliographical references (p. 97-99). / by Julie Steele Chalfant. / M.S.
589

An experimental study of the oil evolution in critical piston ring pack regions and the effects of piston and ring designs in an internal combustion engine utilizing two-dimensional laser induced fluorescence and the impact on maritime economics

Vokac, Adam, 1978- January 2004 (has links)
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2004. / Includes bibliographical references (p. 191-194). / Faced with increasing concern for lubricating, oil consumption and engine friction, it is critical to understand the oil transport mechanisms in the power cylinder system. Lubricating oil travels through distinct regions along the piston ring pack before being consumed in the combustion chamber, with the oil distribution and dominant driving forces varying substantially for each of these regions. This experimental work focuses on specific regions in the piston ring pack. A detailed 2D LIF (Two Dimensional Laser Induced Fluorescence) study has been performed on the oil distribution observed with the LIF generated real time high-resolution images, as were changes in piston and ring design. The results reveal the third land, located between the second compression ring and the oil control ring, oil flow patterns and timing are consistent and predictable at each operating point. Speed and load variation alter the basic flow pattern and oil balance through a corresponding change in inertia and gas dragging effect respectively, with ring design variation instigating specific and repeatable phenomenon onto the consistent oil flow pattern. Second land, the region between the top two compression rings, geometric and flow patterns throughout the entire cycle of a single cylinder spark ignition engine. The impact of speed and load were experimentally changes were found to have a significant impact on inertia driven oil transport; however, their effects on oil consumption were not as clear. As the majority of lubricating oil consumed in the engine crosses the third land at some point, an understanding of the timing and magnitude of the oil transport processes will allow means to be specifically developed to reduce the net oil flow across the third land / (cont.) towards the combustion chamber. This work forms a foundation for developing oil control strategies for the third land and for identifying how and when oil reaches the upper piston ring pack regions that directly contribute to oil consumption. The ability to control, or impact, oil transport on the piston ring pack will have an impact on all engine classes, including engines in the maritime community. This experiment study is directly comparable to small marine engines, and can be used to help reduce maritime exhaust emissions related to lubrication consumption; additionally, this approach would be much more rugged and cost effective then other current technological improvements being investigated. Were a similar 2D LIF experiment to be performed on large slow speed diesel engifes, the annual savings per vessel, assuming only a 10% reduction in lube oil consumption was achieved, could amount to $30,000 as cylinder lube oil is one of the most expensive operating costs for large slow speed diesel engines. / by Adam Vokac. / S.M.
590

Propeller blade design thickness and blockage issues due to source-induced factors

Hunt, David S. (David Sheridan), 1967- January 2001 (has links)
Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, February 2001. / Includes bibliographical references (leaves 58-59). / by David S. Hunt. / Nav.E. / S.M.

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