Mechanical Engineering Commons^™

Blade Design And Validation Of Hydrokinetic Turbine To Harvest Water Current Energy, Setare Sadeqi

University of New Orleans Theses and Dissertations

The innovative aspect of this research lies in the careful integration of cutting-edge technologies throughout the entire process of designing, fabricating, and testing the carbon fiber propeller for the 3-bladed horizontal axis ocean current turbine (OCT). SolidWorks software played a pivotal role in the initial design phase, enabling a meticulous and precise modeling of the propeller's geometry. The utilization of SolidWorks allowed for a detailed exploration of various design parameters, ensuring that the propeller's structure and form were optimized for performance in ocean current conditions. Moving beyond the realm of virtual design, the choice of carbon fiber as the fabrication …

Towing Tank Trials Of Hydrokinetic Turbine Scale Model To Support Marine Energy System Verification, Shahab Rouhi

University of New Orleans Theses and Dissertations

In response to the escalating demand for sustainable energy solutions and the critical reevaluation of conventional fossil fuels due to environmental concerns, this dissertation embarks on a comprehensive exploration of hydrokinetic energy as a promising alternative. The study delves into the underexplored domain of hydrokinetic energy, leveraging innovative methodologies for effective utilization and harnessing, particularly through the development and investigation of hydrokinetic turbines.

In the realm of hydrokinetic energy conversion, our research has exclusively concentrated on horizontal-axis turbines, distinct from other turbine configurations. Noteworthy is the adaptation of a conventional horizontal-axis wind turbine for water currents, revealing enhanced performance through …

Investigation On The Effects Of Biofouling On The Boundary Layer, Adam N. Bacon

University of New Orleans Theses and Dissertations

This study is an investigation of the effect of biofouling on the boundary layer of a flat plate and a NACA 4-digit series foil. Three identical hydrofoils made of resin were placed in the Gulf of Mexico at Grand Isle, Louisiana, and observed and analyzed by marine biologists at the University of New Orleans for their species composition. The resulting biofouling that grew was primarily made up of barnacles and bryozoans. The foils were submerged in an open channel flume at zero incidence and subjected to a series of experiments whose arc-length Reynolds numbers ranged from approximately 13000 to 32000. …

Investigating The Application Of Flettner Rotors On The Great Lakes, Garrett C. Bond

Senior Honors Theses

Climate change is quickly becoming one of the leading problems of the twenty-first century, and the maritime transportation sector is beginning to react. Wind propulsion technologies have been making a comeback led by the Flettner rotor. The deck-mounted, vertical, spinning cylinder generates a lift (or thrust) force perpendicular to the wind by utilizing the Magnus effect. Rotor performance has been studied extensively on many ocean shipping routes, but has not been on the Great Lakes, a region with a large maritime industry. This study aims to assess whether or not Flettner rotors are practical in the region by calculating propulsive …

Numerical Study On Oscillating Flow Over A Flat Plate Using Pseudo-Compressibility In Intermittent Turbulent Regime, Shivank Srivastava Mr.

University of New Orleans Theses and Dissertations

A Computational Fluid Dynamic (CFD) in-house code is developed to study unsteady characteristics of incompressible oscillating boundary layer flow over a flat plate under laminar and intermittently turbulent condition using pseudo-compressible unsteady Reynolds Averaged Navier- Stokes (RANS) model. In the in-house code, the two-dimensional, unsteady conservation of mass and momentum equations are discretized using finite difference techniques which employs second order accurate (based on Taylor series) central differencing for spatial derivatives and second order Runge-Kutta accurate differencing for temporal derivatives. The in-house code employs Fully Explicit-Finite Difference technique (FEFD) to solve the governing differential equations of the mathematical model. In …

Design Of An Ice-Class Propeller For The Mv Yahtse, An Icebreaking, Car And Cargo, Roro Ferry, Mara Kramer

Senior Honors Theses

During early-stage ship design, a propulsion system must be matched with data from a resistance and propulsion analysis to determine the propulsion power required for the vessel to run at its design speed. Typically, this process is completed within NavCAD; however, NavCAD does not have a method to calculate icebreaking resistance or design a propeller to meet the ice-class criteria stipulated by the International Association of Classification Societies (IACS). This paper displays and discusses Python scripts written to complete the resistance and propulsion analysis, propeller optimization, and propeller structural design meeting IACS criteria for an icebreaking, RoRo car and cargo …

Experimental Investigation Into The Boundary Layer Of A Robotic Anguilliform Propulsor, Jonathan R. Eastridge

University of New Orleans Theses and Dissertations

Boundary layer information local to three longitudinal positions has been characterized for a 130 cm long biomimetic self-propulsor known as NEELBOT-1.1 that swims with undulatory anguilliform-like motions, via analysis of stereo particle image velocimetry (PIV) measurements for key moments in the undulation cycle and for numerous combinations of swimming conditions and motion parameters, ideal and non-ideal. No obvious turbulent flow structures or indications of boundary layer separation were observed at nonzero advance speeds, and skin friction coefficients were subsequently estimated for magnitude relative to the dynamic pressure associated with operation at the design swimming speed of U_o = 0.25 …

Deficiencies In The Physics Of Existing Operational Wave And Surge Models, D. T. Resio

Ocean Waves Workshop

No abstract provided.

A New Real-Time Ocean Observing Station On Ship Shoal On Louisiana Shelf, Chunyan Li, Peter Luo, Brian Milan, Wei Huang

Ocean Waves Workshop

One of the major challenges that we are facing in the northern Gulf of Mexico coastal area is the need of a better and reliable offshore met-ocean real time data collection system that supports the mission of Bureau of Ocean Energy Management (BOEM) and other federal and local agencies for coastal management, protection, and restoration, especially along the Louisiana coast. This area has a suite of environmental problems that require the acquisition of real time data for immediate assessment or model-based assessment and predictions that rely on this kind of data. One such system providing this kind of data is …

Update In Us Navy Global Wave Model Forecasting, J. D. Dykes, W. E. Rogers, D. Wang

Ocean Waves Workshop

No abstract provided.

Ocean Waves Workshop 2019 Session 2 Notes, Kaus Raghukumar, Sam Mcwilliams

Ocean Waves Workshop

No abstract provided.

Directional Spectrum Measurements By The Spotter: A New Developed Wave Buoy, Kaus Raghukumar, Grace Chang, Frank Spada, Tim Jannsen

Ocean Waves Workshop

The Spotter is an accurate, low-cost, easily deployable and robust solar powered wave buoy recently developed by Sofar Technologies (formerly Spoondrift). Spotter reduces costs and complexity of surface wave and current measurements, which can be useful for academic, military, and commercial research into surface wave and wave-driven dynamics. We performed a series of validation tests and research experiments with the Spoondrift Spotter. The low-cost and compact Spotter makes it easy to deploy arrays of wave buoys which was previously not feasible (or cost prohibitive) with traditional wave buoys. A well-designed array can provide a direct measurement of the directional wave …

Innovations In Metocean Sensors, Pieter Smit, T. T. Janssen

Ocean Waves Workshop

Real-time observations are critical to understand, predict and estimate the impact of extreme weather events such as extratropical hurricanes and storms. Remote sensing, moored wave buoys and advances in predictive models have greatly advanced understanding and predictive capability of extreme ocean weather. However, due to cost and complexity of traditional moored buoys, in-situ networks are typically sparse and often close to shore and not well suited to drive predictive models over meaningful geophysical scales. Here we will discuss ongoing efforts to extend the capability of the Sofar Spotter to measure marine boundary layer dynamics. With the advancement to more portable …

Ndbc Ocean Wave Observation System Update, Rodney Riley, Randy Stewart, Steven Dinapoli

Ocean Waves Workshop

The U.S. National Oceanic and Atmospheric Administration’s (NOAA) National Data Buoy Center (NDBC) is modifying its ocean wave observation system due to parts obsolescence. The modified system is named Ocean Wave Linux (OWL). OWL will replace the NDBC’s older and now obsolete Digital Directional Wave Module (DDWM). Once OWL completes operational verification, the DDWM will be phased out of the NDBC’s operational weather buoy network.

Feasible Form Parameter Design Of Complex Ship Hull Form Geometry, Thomas L. Mcculloch

University of New Orleans Theses and Dissertations

This thesis introduces a new methodology for robust form parameter design of complex hull form geometry via constraint programming, automatic differentiation, interval arithmetic, and truncated hierarchical B- splines. To date, there has been no clearly stated methodology for assuring consistency of general (equality and inequality) constraints across an entire geometric form parameter ship hull design space. In contrast, the method to be given here can be used to produce guaranteed narrowing of the design space, such that infeasible portions are eliminated. Furthermore, we can guarantee that any set of form parameters generated by our method will be self consistent. It …

Hydrodynamics Of An Anguilliform Swimming Motion Using Morison’S Equation, Naga Sasi Devarakonda

University of New Orleans Theses and Dissertations

In this study, the hydrodynamic performance of anguilliform swimming motion is computed using Morison’s equation. This method was shown to predict the servo motor torques well. The anguilliform swimming motion is sinusoidal with increasing amplitude from head to tail. A “wakeless” swimming motion proposed by Vorus and Taravella (2011) with zero net circulation is considered.

This method is compared to the existing slender body theory and is validated with reference to the experimental results of NEELBOT-1.1 (Potts, 2015). The results for the study indicates that self-propulsion speed of the motion is independent of the oscillating tail amplitude at a constant …

Risk Assessment Of Dropped Cylindrical Objects In Offshore Operations, Adelina Steven

University of New Orleans Theses and Dissertations

Dropped object are defined as any object that fall under its own weight from a previously static position or fell due to an applied force from equipment or a moving object. It is among the top ten causes of injuries and fatality in oil and gas industry. To solve this problem, several in-house tools and guidelines is developed over time to assess the risk of dropped objects on the sub-sea structures. This thesis focuses on compiling and comparing those methods in hope to improve the recommended practices available in the market. A simple modification is done on the in-house tools …

Motion Dynamics Of Dropped Cylindrical Objects, Gong Xiang

University of New Orleans Theses and Dissertations

Dropped objects are among the top ten causes of fatalities and serious injuries in the oil and gas industry. Objects may be dropped during lifting or any other offshore operation. Concerns of health, safety, and the environment (HSE) as well as possible damages to structures require the prediction of where and how a dropped object moves underwater. This study of dropped objects is subdivided into three parts. In the first part, the experimental and simulated results published by Aanesland (1987) have been successfully reproduced and validated based on a two-dimensional (2D) theory for a dropped drilling pipe model. A new …

Numerical Computation Of Transient Response Of 2d Wedge Impact, Naresh Kumar Koyyapu

University of New Orleans Theses and Dissertations

The diverse applications of advanced marine craft ascribed to their high speed and technological advancements has led to the use of stronger and lighter metals in such crafts. High speed, in effect also increases slamming loads as higher speed increases frequency of wave encounter while operating in waves. The present study is limited to wedge impact models. Fundamentally, the study is thus about two-dimensional (2D) wedge impact in water. In an attempt to predict the structural response to impact hydrodynamic force, a beam element based finite element (FE) computer program is written and the results of the code are presented …

Developing And Testing An Anguilliform Robot Swimming With Theoretically High Hydrodynamic Efficiency, John B. Potts Iii

University of New Orleans Theses and Dissertations

An anguilliform swimming robot replicating an idealized motion is a complex marine vehicle necessitating both a theoretical and experimental analysis to completely understand its propulsion characteristics. The ideal anguilliform motion within is theorized to produce ``wakeless'' swimming (Vorus, 2011), a reactive swimming technique that produces thrust by accelerations of the added mass in the vicinity of the body. The net circulation for the unsteady motion is theorized to be eliminated.

The robot was designed to replicate the desired, theoretical motion by applying control theory methods. Independent joint control was used due to hardware limitations. The fluid velocity vectors in the …

Electromechanics Of An Ocean Current Turbine, Vasileios Tzelepis

University of New Orleans Theses and Dissertations

The development of a numeric simulation for predicting the performance of an Ocean Current Energy Conversion System is presented in this thesis along with a control system development using a PID controller for the achievement of specified rotational velocity set-points. In the beginning, this numeric model is implemented in MATLAB/Simulink® and it is used to predict the performance of a three phase squirrel single-cage type induction motor/generator in two different cases. The first case is a small 3 meter rotor diameter, 20 kW ocean current turbine with fixed pitch blades, and the second case a 20 …

Cruise Ship Preliminary Design: The Influence Of Design Features On Profitability, Justin Epstein

University of New Orleans Theses and Dissertations

This thesis provides a means to estimate the physical and performance characteristics of a preliminary cruise ship design. The techniques utilized to estimate these characteristics are showcased in the user-friendly interface known as the Cruise Ship Analysis Tool (CSAT). Using the CSAT, the implications that design feature decisions in the preliminary design stage have on a cruise ship’s profitability is analyzed. Then, the most profitable design feature assemblage among a finite number of varying design feature combinations is estimated and compared among cruise ship designs with different passenger carrying capacities. Profitability is analyzed using the measure of merit (MOM) known …

Reducing Vortex-Induced Vibration Of Drilling Risers With Marine Fairing, Aswin Janardhanan

University of New Orleans Theses and Dissertations

Since the offshore drilling for oil and gas is venturing into ever greater water depths, drilling risers face problems of vortex-induced vibrations due to the currents. Vortexinduced vibrations are a major fluid load and fatigue component on the long, smooth, and slender bodies placed in a fluid flow and measures must be taken to suppress the shedding of the Karman vortex sheets from its edges. One of the ways to reduce the vibration is to use marine fairings which are attached to the drilling risers with the help of weather vanes. In this thesis, CFD analysis based on solving RANS …

Damage Stability Of Inland Towboats, Kyle Stephen Tyson

Senior Honors Theses

The focus of this report is to investigate whether a towboat would be able meet damaged stability requirements. In order to evaluate what type of damage stability requirements could be considered, two damage stability criteria were selected for this investigation: Offshore Supply Vessel and Passenger Vessel Damage Criteria. Two vessels are then evaluated using General Hydrostatic Software (GHS) to find the maximum allowable vertical center of gravity allowed by each set of criteria. These values are then compared to the vessels’ operating conditions to show if the vessels would currently be able to operate. Ultimately it is found that the …

A Wedge Impact Theory Used To Predict Bow Slamming Forces, Ashok Benjamin Basil Attumaly

University of New Orleans Theses and Dissertations

The pressures and impact forces acting on a hull while experiencing bow wave slamming is analyzed using Vorus' Impact Theory. The theory extends the hydrodynamic analysis of planing hulls from simple wedges to irregular shapes using a Boundary Element Method. A Fortran-based code developed by the Author is used to analyze hullforms. Linear strip theory is used to extend the analysis over a three dimensional hull. Post-processing of output data gives hull pressure distributions at different time steps and is visually presentable.

Impact pressure, Impact force, Planing, Wave slamming, Bow impact, Vorus' theory, Boundary Element Method, Linear strip theory

Numerical Modeling Of Lifting Flows In The Presence Of A Free Surface, Leonardo R. Carmona Vasquez

University of New Orleans Theses and Dissertations

This thesis work started as an attempt to create a computational tool to model hydrodynamics problems involving lifting flows. The method employed to solve the problem is potential flow theory.

Despite the fast evolution of computers and the latest developments in Navier-Stokes solvers, such as the Ranse methods; potential flow theory offers the possibility to create or use existing computational tools, which allow us modeling hydrodynamics problems in a simpler manner. Navier-Stokes solver can be very expensive from the computational point of view, and require a high level of expertise in order to achieve reliable models.

Based on the above, …

Correlation Of Shear Strength Between Longitudial And Transverse Specimens, Erasto A. Fernandez

University of New Orleans Theses and Dissertations

In this thesis, new methods for shear strength are proposed and backed up through extensive experimentation, ABAQUS models and data analysis of Titanium welds of three different alloys. The results are compared with those obtained by using the procedure outlined by AWS B4 for calculating Shear Strength in the transverse and longitudinal directions; this equation is widely used by the American Welding Society (AWS) and all those in search of more efficient designs involving welding.

It is a well-documented issue that the equation provided by AWS yields a large discrepancy between the values for shear strength of longitudinal and transverse …