A hydraulic power-take-off was designed and built for outboard
engines typical of those used on small boats and Pacific City-type
dories. An associated hydraulic system was developed for use on
these boats to provide power for fishing machinery. The power for
each system was provided by a hydraulic pump direct-drive...
The design of a more efficient waterjet system for excavation of
commercial crab pots buried in ocean sediment was undertaken. The
work resulted in the design of an improved nozzle with performance
that was shown to be significantly better than that of previously used
nozzles. Greater sand penetration and excavation...
Two types of linear random wave simulation methods are investigated;
viz., (1) Deterministic Spectral Amplitude (DSA) and (2) Nondeterministic
Spectral Amplitude (NSA). These linear simulations are extended to
second-order in a perturbation expansion in the frequency domain by
utilizing a Fast Fourier Transform (FFT).
The nonlinear interaction matrix for waves...
The purpose of this study was to ascertain the potential erosion
impacts associated with ship movements in confined waters. The flow
associated with a ship passage can be separated accordingly: (1) the
propeller wake, (2) flow about the hull, and (3) associated waves.
Each of these areas has been analyzed...
The reliability of ocean systems is dependent on organizational factors. It has been shown that low probability / high consequence system failures are overwhelmingly induced by organizational factors. However, no methodology is yet widely accepted for the evaluation of this phenomenon or its accurate quantification. A qualitative complementary approach is...
Caissons are frequently used in the coastal environment for
breakwaters, jetties, seawalls, and piers. Because a satisfactory
analytical solution to a typical caisson installation has not been
developed, design of a caisson-style structure typically is either
based on physical model testing, which is expensive, or the
structure is designed as...
The surf zone exhibits large energetic signals from wave shoaling and subsequent dissipation due to breaking, forcing circulation. The bathymetry responds to the wave and wave-induced circulation with the growth, transport, and destruction of large scale bathymetric features, such as mega ripples and sand bars. There is an obvious fluctuation...
Steep bathymetric anomalies in the beach profile, such as offshore borrow pits, submerged breakwaters, and nearshore canyons can significantly transform the wave climate through the effects of refraction, diffraction, and reflection. When located in the nearshore region the modified wave climate can also substantially change the location of breaking and...
Two types of boundary element models are developed for the interaction of waves with trenches. The first type is for a two-dimensional domain in the horizontal plane and employs the linear long wave approximations. It is shown that appropriate selection of pit geometries leads to a significant reduction in wave...
Anchors resistant to tensile loads are commonly used in civil engineering practice. Anchors in the marine environment are most frequently used for the mooring of vessels. Only recently, with the expansion of the offshore industry, has the need to develop more reliable anchor systems become necessary. Embedded plate anchors are...
This thesis presents the details of a large-scale laboratory experiment to study the runup velocity on a complex 3D bathymetry. The PIV measurements including the instrumental setup, the recording procedure, and the image processing are presented. Tsunami inundation directly affects the coastal population and is one of the most important...
The rip current field resulting from the transformation of surface gravity waves over offshore submarine canyons is studied. Employing a wave transformation model and a wave-induced circulation model over observed bathymetry we find that rip current circulation cells exist with alongshore spacing of O(1OOm) even though the nearshore bathymetry displayed...