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The use of surface piercing propellers (SPPs) shows promise for high speed operation by virtually eliminating appendage drag, which can be as much as 30 percent of the total drag on a vehicle at high speeds. The scarcity of available systematic test data has made reliable performance prediction difficult. The primary objective of this research is to obtain experimental performance prediction data that can be used in SPP design. In a series of open water tests in a non-pressurized towing tank facility, force transducer measurements were taken at tip immersion ratios from 0.5 to .33, yaw angles from 0° to 30° and inclination angles from 0° to 15° over a range of advance ratios from 0.8 to 1.8. Force transducer measurements were taken for thrust, torque, side forces and moments. These results will help develop a baseline for the verification of SPP performance prediction. / by Justin M. Lorio. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

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Historically, the analysis of ship motion and loading responses has been performed in the frequency domain with both linear response amplitude operators and wave energy density spectra. This method, therefore, did not account for the nonlinear nature of waves. A more precise method is to obtain the response in the time domain, processing non-linear wave data with a linear response amplitude operator. Since the input is non-linear, even though the system is linear, the output will also be non-linear. This resultant data can then be used to generate a more accurate design of seaworthy vessels. Furthermore the linear frequency domain method does not account for the presence or effects of wave groups. This study shows the improved accuracy in the response obtained by accounting for non-linearities and furthermore indicates that wave groups affect the vertical relative motion of a moored ship (zero-speed).

Thesis (M.Eng.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 77-79.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003. / Thesis by Martin G. Sarch. Includes bibliographical references. Available online at two web addresses.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Fotis A. Papoulias, Charles N. Calvano. Includes bibliographical references (p. 111-112). Also available online.

Simulation techniques and a Volterra functional polynomial are applied as two alternative methods of calculating ship roll response to irregular waves. The roll motion is modeled by a single degree of freedom differential equation, with two alternative nonlinear damping functions. Estimation techniques are developed to obtain the coefficients of the damping functions from decay tests and from forced rolling tests. A linear plus quadratic form of damping function is found to be slightly preferable to a linear plus cubic form. The roll response process is found to be non-Gaussian, and characterised by negative values of the coefficient of kurtosis. Simulation results agree well with results obtained from the functional polynomial for low response levels, but show increasing disagreement as the response level increases, due to divergence of the functional polynomial representation. Analyses of results from model tests in irregular waves and from sea trials confirm the non-Gaussian nature of the roll response. A "constrained" form of the generalised gamma distribution function is found to provide an improved fit to the roll maxima and tothe roll minima, as compared to the Rayleigh distribution. The model tests also show some asymmetry in the roll response, which is not predicted by the theoretical model. It is suggested that this asymmetry may primarily be due to the combined effect of horizontal drift forces and the restraining system used to keep the model on station.

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