Ocean Engineering Commons^™

Experimental Material Analysis And Load Monitoring Of Polyurethane–Steel Belts Subjected To Static And Cyclic Dynamic Loading: Implications For Continuous Mooring Line Systems In Wave Energy Converters, Youssef Mohamed

Electronic Theses and Dissertations 2020 - Present

This study experimentally investigates the mechanical and viscoelastic behavior of a steel-cord-reinforced polyurethane synchronous belt capable of withstanding continuous cyclic loading as a potential compliant mooring element for WEC applications. Quasi-static and cyclic tensile tests were conducted to characterize the belt's mechanical response. The quasi-static determined that the belt behaved as a stiff, low-strain tensile member. Under approximately 100 kgf, the belt extended by about 0.107mm over a 250mm gauge length, apparent tensile modulus of 5.41GPa, an axial rigidity of 2.44MN, and an equivalent line stiffness of 9.75MN/m. Cyclic tensile testing showed high dynamic stiffness with stiffness-transfer ratio of 0.924. …

Object Avoidance Onboard An Autonomous Underwater Vehicle In Support Of Geomagnetic Based Navigation System, Eric Benavidez

Electronic Theses and Dissertations 2020 - Present

The objective of this thesis was to collect and analyze magnetic field data in the vicinity of the Mercy, Tracey, and Jay Scutti with an autonomous underwater vehicle (AUV) and a forward mounted magnetometer. The collected data was used to develop geomagnetic contour maps and magnetic thresholds of known anomalies to compare the results with validated sources such as NOAA.

In addition, this collected data was used to develop a Gazebo simulation which accurately modeled the magnetic field data and ocean effects of the Fort Lauderdale Shipwreck Trail. This Gazebo simulation allowed for proper testing and refinement of object avoidance …

Characterization Of Various Corrosion-Resistant Rebars Embedded In Concrete After 20 Years Of Exposure, Samantha Mavrak

Electronic Theses and Dissertations 2020 - Present

In aggressive marine environments, the deterioration of reinforced concrete structures is primarily caused by chloride-induced corrosion of embedded carbon steel reinforcement, resulting in concrete cracking, spalling, and costly maintenance or premature replacement. Corrosion-resistant reinforcement has been developed to mitigate these effects; however, long-term field performance data remain limited. This study evaluates the long-term corrosion performance of several corrosion-resistant rebars embedded in simulated deck slab concrete specimens following approximately 20 years of chloride exposure.

Concrete specimens containing 304SS, 316SS, and 2304 duplex SS, two types of clad reinforcement (316SS with carbon steel core), and an intermediate alloy with 12% Cr were …

Enhancement Of A Copolyester’S Impact Resistance Via Inorganic Reinforcement, David Felipe Gonzalez

Electronic Theses and Dissertations 2020 - Present

Thermoplastic copolyester elastomers (TPEEs) are widely used in engineering applications because of their flexibility, toughness, and chemical resistance. However, prolonged exposure to marine environments can reduce their mechanical performance through moisture-induced degradation. This research investigated the use of titanium dioxide (TiO2) nanoparticles and APTES-functionalized TiO2 nanoparticles to improve the mechanical, thermal, and environmental durability of Hytrel 5556. Nanocomposites containing 1 wt.% and 2 wt.% TiO2 were fabricated through melt blending and compression molding. Mechanical properties were evaluated through tensile, compression, flexural, and impact testing, while thermal behavior was characterized using differential scanning calorimetry (DSC). Nanoparticle dispersion was examined using scanning …

Aquaculture Ecosystem Modeling Aeration Efficiency Optimization Using Cfd, Gabriela Reyes Gomez

Electronic Theses and Dissertations 2020 - Present

The Harbor Branch Oceanographic Institute (HBOI) is developing the Intelligent and Resource Efficient Pond Aquaculture (IREPA) project, which aims to improve aquaculture management through the integration of predictive models and automated technologies. This approach seeks to transition traditional practices toward data-driven systems capable of supporting informed decision-making for aeration management.

This study investigates the effectiveness of different aerator configurations on hydrodynamic circulation and dissolved oxygen (DO) distribution in aquaculture ponds using computational fluid dynamics (CFD). A model was developed in ANSYS Fluent, where the aerator was represented using a power-based formulation and implemented as a moving wall boundary condition. Dissolved …

Optimization Of A Point Absorber Wave Energy Converter (Wec), Rutwa Dilipkumar Nagar

Electronic Theses and Dissertations 2020 - Present

This study examines the performance and optimization of a point absorber wave energy converter with a partially submerged spherical float. A comprehensive open-source computational framework integrates frequency-domain hydrodynamic analysis with time-domain simulation using Capytaine, BEMIO, and WEC-Sim. Hydrodynamic coefficients such as added mass, radiation damping, and excitation forces are calculated and integrated into the governing equation of motion using the Cummins formulation. A parametric analysis varies the float diameter and geometric configurations across several cases. Hydrodynamic coefficients and response amplitude operators are assessed to analyze system behavior and resonance characteristics. Results indicate consistent trends in normalized added mass, with radiation …

Acoustic Response Of The Cnt-Reinforced Multilayered Acoustic Foam Composites (Mafc), Trey Brauch

Electronic Theses and Dissertations 2020 - Present

Acoustic metamaterials are engineered materials designed to control and manipulate sound propagation. Many such systems incorporate acoustic foams due to their porous structure, low density, and high specific surface area, which promotes efficient sound absorption. However, a major limitation of conventional acoustic foams -particularly open-cell varieties- is their lack of waterproofing, rendering them unsuitable for underwater or moisture-prone environments. To address this limitation, a multilayered acoustic foam composite (MAFC) was developed as a lightweight, waterproof structure with enhanced sound absorption performance. The MAFC consists of five layers: the first and fifth layers are aluminum foam, providing structural integrity; the second …

On The Drainage Vortices Of Liquid In A Container With Two Outlets, Radivoje Stankovic

Electronic Theses and Dissertations 2020 - Present

Vortices that form over multiple drainage ports may exhibit a distinct, periodic alternating behavior, whereby the air core moves periodically between different drainage ports. The physical processes which govern this behavior have not yet been explained, despite the widespread and thorough attempts to describe the flow of water through single or multiple outlets. Early experiments on the alternating behavior of this vortex resulted in a nondimensional relation between the alternating frequency and water height and container geometry with an R2 = 0.91. Subsequent 2D PIV measurements of the flow were performed at different laser heights of 25 mm and 128 …