Thesis (S.M. in Ocean Systems Management)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2002. / Includes bibliographical references (leaves 135-137). / by Jan Meyer. / S.M.in Ocean Systems Management

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2005. / Includes bibliographical references (p. 67-70). / An effective physics-based model has been developed that is capable of reliably predicting the motion of a three-dimensional mine-shaped object impacting the water surface from air and subsequently dropping through the water toward the sea bottom. This deterministic model, MINE6D, accounts for six-degree-of-freedom motions of the body. MINE6D allows for physics-based modeling of hydrodynamic effects due to water impact, viscous drag associated with flow separation and vortex shedding, air entrainment, and realistic flow environments. Unlike existing tools that are limited to plane motions only, MINE6D captures the myriad of complex three-dimensional motions of cylindrical mines observed in field and laboratory experiments. In particular, accounting for the three-dimensional viscous drag and air entrainment cavity produces an accurate prediction of the velocity, trajectory, and orientation of mines freely dropping in the water. The model development and effects on body motion are presented for both viscous drag and air entrainment cavities. / (cont.) Monte Carlo simulation using MINE6D is then used to obtain statistical characterization of mine motions in practical environments. These statistical results are not only the essential input for stochastic bottom impact and burial predictions of mines but also important for the design of mines. / by Jennifer L. Mann. / S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1987. / Bibliography: v. 2, leaves 287-291. / by Mark James Gray. / M.S.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, February 1997. / Includes bibliographical references (leaves 119-123). / by Xuemei Zhu. / Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1995. / Includes bibliographical references (leaves 54-55). / by Hua-Yang Wu. / M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1999. / Includes bibliographical references (leaves 122-124). / by Roger J. Anderson. / S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1994. / Includes bibliographical references (leaves 119-122). / by Jie Zhang. / M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1997. / Includes bibliographical references (leaves 100-104). / by Paeng, Dong-Guk. / M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1998. / Includes bibliographical references (p. 88-89). / The hover actuator system is a proof of concept platform. The design models the ability of a flapping foil to assist an undersea vehicle's shallow water sea-keeping performance. Goals of this study are to demonstrate an effective regime of foil motion amplitude, frequency, pitch angle offset, pitch angle amplitude and phase angle for two types of motion. Using the time-averaged thrust coefficient, I find that the lower frequencies provide the highest thrust coefficient of 3.1 at G0=600, hdc= 1.5, and f=0.4Hz for the treading water mode. Significantly lower thrust coefficients are observed for the figure eight mode with maximum of 1.8 occurring at G0=300, hdc=1, and f-0.2Hz. In addition to finding the optimal regime of thrust coefficient, the total thrust is also analyzed to find the regimes of absolute maximum thrust. Again, for the water treading mode the peak thrust was 24Newtons at 00=600, hjc=2.5, and f=0.6Hz; and for the figure eight mode the peak thrust of 7.5Newtons occurs at 00=450, hdc=2.7, and f-0.2Hz. Finally, the rationale of using such an apparatus, arguments, and test results are discussed in conclusion. / by J. Paul Marquardt. / S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1997. / Includes bibliographical references (leaves 116-121). / by Gregory Robert Thomas. / Ph.D.