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Full-Text Articles in Engineering
Hydrodynamic Ram Analysis Of Bonded Composite Fuel Tanks, Teddy Sedalor
Hydrodynamic Ram Analysis Of Bonded Composite Fuel Tanks, Teddy Sedalor
Theses and Dissertations
Military aircraft are tested against a variety of ballistics threats as part of their design to assess their vulnerability. One aspect of this approach/requirement is Hydrodynamic Ram testing which accounts for projectile impact into fuel tanks. Hydrodynamic Ram (HRAM), which occurs due to overpressure created in an enclosed fluid as a result of the transfer of energy and momentum from a penetrating projectile, can be quite destructive to the enclosing structure, which makes testing expensive. Therefore the need arises for numerical methods to supplement the testing and provide more test data than can be obtained directly from the article test. …
Numerical Simulations Of Comprehensive Hydrodynamic Performance Of Darpa Suboff Submarine, Kenshiro Takahashi
Numerical Simulations Of Comprehensive Hydrodynamic Performance Of Darpa Suboff Submarine, Kenshiro Takahashi
Theses and Dissertations
A numerical study of the DARPA SUBOFF model using computational fluid dynamics (CFD) has been presented for developing a CFD application procedure to compute the hydrodynamic performance of underwater vehicles, including submarines. Several configurations, such as bare hull, fairwater, sterns, and/or ringwing-appended hulls, were examined for the straight-ahead, steady translation and turning, and self-propelled conditions. A systematic study was conducted to ensure an adequate computational domain expansion and reasonable prism layer mesh properties for solutions independent of the parameters. The hydrodynamic forces exerted on the hull and the appendages were verified and validated in accordance with a published methodology under …
Integration Of Inboard Propulsion In Shock Mitigating Membrane Hull Technology, Korrey Rotkiske
Integration Of Inboard Propulsion In Shock Mitigating Membrane Hull Technology, Korrey Rotkiske
Theses and Dissertations
Membrane Hull Technology is a strength based marine vessel design concept that seeks to utilize the in-plane properties of fiber reinforced composites to generate a lighter weight vessel with inherent shock mitigation benefits. MHT has been applied on several Naval crafts yet the design features of inboard propulsion systems have not been addressed. Inboard propulsion systems are a very common form of propulsion used in many types of marine vessels especially larger vessels. This thesis seeks to overcome the inboard engine mounting challenges of MHT which limits use of this technology in the marine industry. The fundamental design elements of …
Semantic And Qualitative Physics-Based Formal Reasoning For Functional Decomposition In Mechanical Design, Xiaoyang Mao
Semantic And Qualitative Physics-Based Formal Reasoning For Functional Decomposition In Mechanical Design, Xiaoyang Mao
Theses and Dissertations
Function modeling plays an essential role in academy design studies, yet a lack of acceptance in industry. A possible reason is that the designer must have well understand of the controlled vocabularies and grammars to utilize this method. The research presented in this dissertation is to fill this gap so that designers can use function-based design method without relevant knowledge. In graph-based function models, the function verbs and flow nouns are usually chosen from predefined vocabularies. The vocabulary class definitions, combined with function modeling grammars defined at various levels of formalism, enable function-based reasoning. However, the text written in plain …
Numerical Modeling Of Phase Transition In Shock Tube Problem, Man Minh Le
Numerical Modeling Of Phase Transition In Shock Tube Problem, Man Minh Le
Theses and Dissertations
In this work, we developed a numerical model for phase transition in shock-tube problem. This work focused on simulating shock-tube problem and the numerical framework is based on a two-phase flow model. Our simulation tool is an in-house FORTRAN multiphase compressible flow solver, RocSDT [31]. Specifically, this involves the Euler equations along with the Stiffened Gas Equation of State (EOS), an interface of liquid-gas type, and the effects of heat and mass transfer due to phase transition. This thesis described the implementation and incorporation of a phase transition model into a system of five partial differential equation model and the …
A Coastal Estuarine Ensemble Forecasting System, Peyman Taeb
A Coastal Estuarine Ensemble Forecasting System, Peyman Taeb
Theses and Dissertations
This research has been conducted in an effort to reduce the computational costs associated with high-resolution coastal estuarine modeling in ADCIRC. It was proposed that model scalability will be significantly enhanced if the conventional single-domain technique is replaced by a nesting method. Preliminary testing indicated the potential for 50% to more than 80% simulation runtime reduction (depending on the study site) by implementing a nesting technique. Once the concept was proved, the development of an operational, ensemble-based forecasting system, exclusively for the east coast of Central Florida and the IRL system, was implemented. The system, referred to as Ensemble Multistage, …
Advancing Numerical Calculation Of Mixed Sized Sediment Transport And Morphology Change, Irene Margaret Watts
Advancing Numerical Calculation Of Mixed Sized Sediment Transport And Morphology Change, Irene Margaret Watts
Theses and Dissertations
Numerical modeling of sediment transport and morphologic change has become a powerful tool for studying and working in the coastal zone. Numerical calculation can assist in a broad range of projects from regional sediment management to beach nourishment as well as evaluating environmental aspects of dredging and placement and implications to water quality and turbidity. Success in application of these tools is partially dependent on the quality of characterization of the sediments in the field. These parameters could include grain size, mineralogical composition, specific gravity and fall velocity. Sediment transport formulations are sensitive to the spatial representation of the sediments …
Developing An Interview Protocol For An Engineering Design Capstone Course To Measure Student Motivation And Engineering Identity, Mckenzie Clark
Developing An Interview Protocol For An Engineering Design Capstone Course To Measure Student Motivation And Engineering Identity, Mckenzie Clark
Theses and Dissertations
This thesis examines the process of developing an effective in-depth interview protocol to measure student motivation and engineering identity. Several methods were employed during the creation, refining, and analysis portions of this study to ensure reliability and validity of the qualitative research instrument. In a multifaceted course such as senior capstone design, it is integral to ensure students are receiving a value adding experience. In most universities across the United States, senior capstone design is a multiple semester sequence where design is heavily emphasized and students are encouraged to test their skills, both technical and nontechnical, by solving and implementing …
Performance Analysis Of A Parabolic Trough Solar Collector, Feras Abdullah Mohammed Alghamdi
Performance Analysis Of A Parabolic Trough Solar Collector, Feras Abdullah Mohammed Alghamdi
Theses and Dissertations
Solar energy technologies are growing vastly in both developed and developing countries. The parabolic trough solar collector (PTSC) technology is the most widely used system among concentrated solar technologies. In this thesis, three models were developed to investigate the performance of the PTSC; these models are 2D & 3D numerical models and 1D analytical model. Each model considers three absorber tube configurations, vacuum annulus, air-filled annulus, and bare absorber tube. The specifications of the Luz LS-2 PTSC were used throughout the study. Since the study considers the 3D model, a realistic non-uniform heat flux distribution around the receiver tube was …
Redeployment And Demonstration Of The Video Guidance Sensor For Proximity Maneuvers, Xiangyi Li
Redeployment And Demonstration Of The Video Guidance Sensor For Proximity Maneuvers, Xiangyi Li
Theses and Dissertations
This paper presents the redeployment and demonstration of the Photogrammetric Video Guidance Sensor (PVGS) as a position and attitude sensor for proximity maneuvers and formation flight of small spacecraft. The original PVGS was developed to use a smartphone as its hardware and an Android application as its software; however, this paper provides a possibility for using a smaller and cheaper single-board computer, Raspberry Pi as new hardware, and for using a Java program run in Linux as its software. We finally achieved the approximate performance compared to the original PVGS. At the current stage, a PID controller was supposed to …
A Mixed Method Study On The Impact Of Industry Sponsored Projects On Senior Capstone Design Student’S Motivational Factors, Devanshi Shah
A Mixed Method Study On The Impact Of Industry Sponsored Projects On Senior Capstone Design Student’S Motivational Factors, Devanshi Shah
Theses and Dissertations
This thesis examines the change in student motivation through a yearlong senior capstone design course with respect to their choice of project type. The senior capstone design projects offered at the university fall into one of two major project types: industry sponsored and nonindustry sponsored. The students opt for either of the two major project types based on their interest and future career goals. The students were given an adapted version of Motivated Strategies for Learning Questionnaire (MSLQ) to self-identify their motivation levels by rating various questions on a 7-point Likert scale. The surveys were conducted at two different points …
Hardware-In-The-Loop Testbed For The Dynamics Of Spacecraft Rendezvous And Capture, Stephen Thiam Choy Kwok Choon
Hardware-In-The-Loop Testbed For The Dynamics Of Spacecraft Rendezvous And Capture, Stephen Thiam Choy Kwok Choon
Theses and Dissertations
As more satellites are launched into orbit, the amount of space debris objects and defunct satellites in orbit that pose a risk to existing operational space systems is expected to grow. In addition, the risk of collision with defunct systems and space debris increase operational fuel cost for active satellites that have to perform avoidance maneuvers. When a satellite’s propulsion or attitude navigation system malfunction, this may cause the satellite to become defunct, potentially becoming a risk to other active space systems. A way to counter defunct satellite systems, is through robotic on-orbit servicing and active space debris removal as …
A Game Theory Motivated Approach To Analyzing Modularity In Automotive Systems, David John Thiess Jr.
A Game Theory Motivated Approach To Analyzing Modularity In Automotive Systems, David John Thiess Jr.
Theses and Dissertations
This paper examines the effect of integrated and modular design on consumers and manufacturers and seeks to determine if there is an optimal design that benefits both. Some consumers perceive the automotive industry to design vehicles with only the company’s benefit in mind, rather than the desires of the consumer. However, the automotive industry seeks to please consumers, while minimizing the cost of production. A game-theoretic based model was developed that was used to determine if there existed a level of modularity for a system that optimized for both the manufacturer and consumer. The game model consisted of two players, …
Acceleration, Braking, And Steering Controller For Polaris Gem E2, Matthew Benton Salfer-Hobbs
Acceleration, Braking, And Steering Controller For Polaris Gem E2, Matthew Benton Salfer-Hobbs
Theses and Dissertations
This paper discusses the design and simulation of lane keeping and velocity controllers for a Polaris GEM e2. The controllers were designed to be implemented in Florida Institute of Technology’s entry for the Intelligent Ground Vehicle Competition self-drive challenge. The software and physical implementation of actuators were included to control the acceleration, braking, and steering. The accelerator pedal was replaced with a set of digitally controlled potentiometers, the brake pedal was replaced with a linear actuator, and the steering column was replaced with a stepper motor. Each actuator was controlled by a Raspberry Pi 3. A sliding mode controller was …
Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan
Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan
Theses and Dissertations
Membrane Hull Technology (MHT) was initially developed for the United States Navy Rigid-Hull Inflatable Boats (RHIB) as an alternative structure design to provide weight savings and shock mitigation. MHT accomplishes this by veering away from traditional hull design and utilizing a grid like system with an increased number of longitudinal stringers and transverse frames with a significantly lower moment of inertia when compared to traditional stringers and bulkheads. The decrease in stiffness allows for increased deflection in the hull during high load events with the added benefit of shock absorption. This technology, developed by Structural Composites Inc., has been successfully …
Feasibility Study And Hydrodynamics Of Transformable Submersible Hydrofoil Trimaran, Yipeng Pan
Feasibility Study And Hydrodynamics Of Transformable Submersible Hydrofoil Trimaran, Yipeng Pan
Theses and Dissertations
It has been the endeavor of naval architects to design innovative hull forms to address the political, socio-economic climate and sustainability around the world. It is imperative that countries be able to protect their sea lanes and coastal zones from surveillance and infiltration from hostile foreign entities. Hence there is a need to develop radically different hull form, which possess the elusive ability and are capable of high-speed. In order to fulfill the idea, the hypothesis envisioned in this thesis is: the Transformable Submersible Hydrofoil Trimaran (TSHT) as an innovative and ground breaking hull form would address the feasibility of …
Energy, Exergy And Economic Analysis Of A Micro-Cchp System, Ganesh Vinayak Doiphode
Energy, Exergy And Economic Analysis Of A Micro-Cchp System, Ganesh Vinayak Doiphode
Theses and Dissertations
Combined cooling, heating and power generation (CCHP) systems can be utilized for commercial or multi-family residential buildings as efficient and reliable means to satisfy building power requirements and thermal loads. In the present study, a CCHP system consist of a Bryton cycle, an Organic Rankine cycle (ORC) and an absorption Ammonia-water cycle is considered. A detailed model is developed via MATLAB to assess the performance of the considered cycle from energy, exergy and economic perspectives. Appropriate ranges for inputs are considered and the first law efficiency, second law efficiency and ECOP of the cycle are determined as 77.17%, 33.18% and …
Tuning Of The Zero Dispersion Point For Micro Electrical Mechanical Systems, Rebekah Mercedes Blackwell
Tuning Of The Zero Dispersion Point For Micro Electrical Mechanical Systems, Rebekah Mercedes Blackwell
Theses and Dissertations
Resonant micro-electromechanical systems (MEMS) are increasingly common in applications, including inertial sensors and frequency sources. These devices operate at resonance and take advantage of their size, ability to integrate with electronics, and light damping. The performance of these devices can be improved by operation at higher vibration amplitudes, but they often begin to exhibit frequency shifts near resonance as the amplitude is increased, due to nonlinear stiffness effects. Previous works have sought to balance nonlinearities in order extend the linear dynamic range (LDR) of these resonators. The focus of this thesis is to characterize, for design purposes, another possible operating …
Experimental And Numerical Analysis Of The Drag Force On Surfboards With Different Shapes, Omar Lahlou
Experimental And Numerical Analysis Of The Drag Force On Surfboards With Different Shapes, Omar Lahlou
Theses and Dissertations
The aim of the present study is to define the hydrodynamic resistance of surfboards with different designs. Decreasing the drag acting on a board helps the surfer to attain higher surfing performances. It helps to attain higher speeds and maneuvering for the surfer. In this thesis, theoretical, experimental and computational approaches are used to explain how the drag changes with different surfboard shapes. Four surfboards with varying shapes were towed at different speeds and the resulting force was recorded. Two computational models were developed using Star CCM and Flowsquare to confirm the experimental results. The drag force on the boards …
Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov
Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov
Theses and Dissertations
The thesis analyzes a flight software of a new free flying robot Astrobee, that will change the current Synchronized Position Hold Engage Reorient Experimental Satellites (SPHERES) on International Space Station (ISS). First, the main components of the flight software were examined: Robotic Operating System (ROS), Gazebo and MATLAB. During that phase, functionalities of ROS, Gazebo and MATLAB were analyzed, and it was found how these components integrate between each other to build Astrobee flying software. Next, simulation of two Astrobees performing “in-home” and “torque” maneuvers was executed. After a successful completion of simulation, results of Astrobee’s trajectory was recorded. Then, …
Numerical Study On Seakeeping Performance Of Hydrofoil Assisted Submersible Trimaran (Hast), Yuchen Lin
Numerical Study On Seakeeping Performance Of Hydrofoil Assisted Submersible Trimaran (Hast), Yuchen Lin
Theses and Dissertations
The present study focuses on the seakeeping characteristics of Hydrofoil Assisted Submersible Trimaran (HAST). The seakeeping performance is an important part in ship design because it effects the comfort, control, resistance and safety. The motions in wave will reduce the performance of ship which is designed and optimized in calm water. The heave and pitch motions of HAST in calm water and regular waves have been investigated by STAR CCM+, a CFD analysis program. The theory of numerical simulation based on STAR CCM+ has been presented. The basic theory of seakeeping performance studies has been discussed. A series of simulations …