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Articles 1141 - 1170 of 1209
Full-Text Articles in Mechanical Engineering
Discovery Learning Experiments In A New Machine Design Laboratory, Mark L. Nagurka, Fernando Rodriguez Anton
Discovery Learning Experiments In A New Machine Design Laboratory, Mark L. Nagurka, Fernando Rodriguez Anton
Mechanical Engineering Faculty Research and Publications
A new Machine Design Laboratory at Marquette University has been created to foster student exploration with hardware and real-world systems. The Laboratory incorporates areas for teaching and training, and has been designed to promote “hands-on” and “minds-on” learning. It reflects the spirit of transformational learning that is a theme in the College of Engineering.
The goal was to create discovery learning oriented experiments for a required junior-level “Design of Machine Elements” course in mechanical engineering that would give students practical experiences and expose them to physical hardware, actual tools, and real-world design challenges. In the experiments students face a range …
Biogeography-Based Optimization For Hydraulic Prosthetic Knee Control, Tim Wilmot, George Thomas, Berney Montavon, Rick Rarick, Antonie J. Van Den Bogert, Steve Szatmary, Daniel J. Simon, William Smith, Sergey Samorezov
Biogeography-Based Optimization For Hydraulic Prosthetic Knee Control, Tim Wilmot, George Thomas, Berney Montavon, Rick Rarick, Antonie J. Van Den Bogert, Steve Szatmary, Daniel J. Simon, William Smith, Sergey Samorezov
Electrical and Computer Engineering Faculty Publications
We discuss open-loop control development and simulation results for a newly-developed cyber-physical system (CPS) used as a semi-active, above-knee prosthesis. The control signal of our CPS consists of two hydraulic valve settings that control a linear cylinder actuator and provide torque to the prosthetic knee. We develop open-loop control using biogeography-based optimization (BBO), which is a recently developed evolutionary algorithm. The research contributes to the field of cyber-physical systems by showing that it is possible to find effective open-loop control signals for our newly proposed semi-active hydraulic knee prosthesis through a dual-system optimization process which includes both human and robot …
Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox
Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox
Undergraduate Honors Capstone Projects
Team Hot Stuff designed a thermal capacitor for Senior Design I at Utah State University. This thermal capacitor is intended for use in the food service industry as a low-cost alternative to chafers. Chafers are platters which use oil burners to keep food warm. The client for this thermal capacitor is Thermal Management Technologies (TMT), a company specializing in thermal science solutions whose mission is “to provide simple, practical thermal science solutions to a wide range of platforms including: Industry, Defense, and Space”1. The founder and president of TMT, Dr. J. Clair Batty, serves as a mentor for …
Assess The Accuracy Of The Variational Asymptotic Plate And Shell Analysis Using The Generalized Uni, Luciano Demasi, Wenbin Yu
Assess The Accuracy Of The Variational Asymptotic Plate And Shell Analysis Using The Generalized Uni, Luciano Demasi, Wenbin Yu
Mechanical and Aerospace Engineering Faculty Publications
The accuracy of the Variational Asymptotic Plate and Shell Analysis (VAPAS) is assessed against several higher order, zig zag and layerwise theories generated by using the invariant axiomatic framework denoted as Generalized Unified Formulation (GUF). These theories are also compared against the elasticity solution developed for the case of a sandwich structure with high Face to Core Stiffness Ratio. GUF allows to use an infinite number of axiomatic theories (Equivalent Single Layer theories with or without zig zag effects and Layerwise theories as well) with any combination of orders of the displacements and it is an ideal tool to precisely …
Dnad, A Simple Tool For Automatic Differentiation Of Fortran Codes Using Dual Numbers, Wenbin Yu, Maxwell Blair
Dnad, A Simple Tool For Automatic Differentiation Of Fortran Codes Using Dual Numbers, Wenbin Yu, Maxwell Blair
Mechanical and Aerospace Engineering Faculty Publications
DNAD (dual number automatic differentiation) is a simple, general-purpose tool to automatically differentiate Fortran codes written in modern Fortran (F90/95/2003) or legacy codes written in previous version of the Fortran language. It implements the forward mode of automatic differentiation using the arithmetic of dual numbers and the operator overloading feature of F90/95/2003. Very minimum changes of the source codes are needed to compute the first derivatives of Fortran programs. The advantages of DNAD in comparison to other existing similar computer codes are its programming simplicity, extensibility, and computational efficiency. Specifically, DNAD is more accurate and efficient than the popular complex-step …
Thermal Conductivity Profile Determination In Proton-Irradiated Zrc By Spatial And Frequency Scanning Thermal Wave Methods, C. Jensen, M. Chirtoc, N. Horny, J. S. Antoniow, H. Pron, Heng Ban
Thermal Conductivity Profile Determination In Proton-Irradiated Zrc By Spatial And Frequency Scanning Thermal Wave Methods, C. Jensen, M. Chirtoc, N. Horny, J. S. Antoniow, H. Pron, Heng Ban
Mechanical and Aerospace Engineering Faculty Publications
Using complementary thermal wave methods, the irradiation damaged region of zirconium carbide (ZrC) is characterized by quantifiably profiling the thermophysical property degradation. The ZrC sample was irradiated by a 2.6 MeV proton beam at 600 °C to a dose of 1.75 displacements per atom. Spatial scanning techniques including scanning thermal microscopy (SThM), lock-in infrared thermography (lock-in IRT), and photothermal radiometry (PTR) were used to directly map the in-depth profile of thermal conductivity on a cross section of the ZrC sample. The advantages and limitations of each system are discussed and compared, finding consistent results from all techniques. SThM provides the …
The Determination Of Drag And Lift Forces Of A Rigid Beam Located Within A Turbulent Boindary Layer By Means Of Large Eddy Simulation Modeling, Santiago Helman
The Determination Of Drag And Lift Forces Of A Rigid Beam Located Within A Turbulent Boindary Layer By Means Of Large Eddy Simulation Modeling, Santiago Helman
Dissertations and Theses
"Recent studies such as those conducted by Akaydin, Elvin and Andreopoulos in [1] have described and quantified the electrical power that can be extracted from a moving flow by the implementation of energy harvesters. In such study, a flexible cantilevered beam was fitted with a cylindrical prism at the free end and placed within a uniform flow field. Due to the vortex shedding generated by the prism (e.g. Von Karman vortices) the beam was found to oscillate about the undisturbed position. The beam in question was then outfitted with a piezoelectric material in order to translate the transient strain energy …
Simulating Large Deformation Of Intraneural Ganglion Cyst Using Finite Element Method, Sachin Lokhande
Simulating Large Deformation Of Intraneural Ganglion Cyst Using Finite Element Method, Sachin Lokhande
Dissertations, Master's Theses and Master's Reports - Open
Intraneural Ganglion Cyst is disorder observed in the nerve injury, it is still unknown and very difficult to predict its propagation in the human body so many times it is referred as an unsolved history. The treatments for this disorder are to remove the cystic substance from the nerve by a surgery. However these treatments may result in neuropathic pain and recurrence of the cyst. The articular theory proposed by Spinner et al., (Spinner et al. 2003) considers the neurological deficit in Common Peroneal Nerve (CPN) branch of the sciatic nerve and adds that in addition to the treatment, ligation …
Influence Of Mechanical And Thermal Boundary Conditions On Stabilizing/Destabilizing Mechanisms In Evaporating Liquid Films, Aneet Dharmavaram Narendranath
Influence Of Mechanical And Thermal Boundary Conditions On Stabilizing/Destabilizing Mechanisms In Evaporating Liquid Films, Aneet Dharmavaram Narendranath
Dissertations, Master's Theses and Master's Reports - Open
Liquid films, evaporating or non-evaporating, are ubiquitous in nature and technology. The dynamics of evaporating liquid films is a study applicable in several industries such as water recovery, heat exchangers, crystal growth, drug design etc. The theory describing the dynamics of liquid films crosses several fields such as engineering, mathematics, material science, biophysics and volcanology to name a few.
Interfacial instabilities typically manifest by the undulation of an interface from a presumed flat state or by the onset of a secondary flow state from a primary quiescent state or both. To study the instabilities affecting liquid films, an evaporating/non-evaporating Newtonian …
Development Of The Ecocar 3 Proposal And Guidelines For Modeling And Design In Year One Of Ecocar 3, Tyler B. Daavettila
Development Of The Ecocar 3 Proposal And Guidelines For Modeling And Design In Year One Of Ecocar 3, Tyler B. Daavettila
Dissertations, Master's Theses and Master's Reports - Open
This report summarizes the work done for the Vehicle Powertrain Modeling and Design Problem Proposal portion of the EcoCAR3 proposal as specified in the Request for Proposal from Argonne National Laboratory.
The results of the modeling exercises presented in the proposal showed that:
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An average conventional vehicle powered by a combustion engine could not meet the energy consumption target when the engine was sized to meet the acceleration target, due the relatively low thermal efficiency of the spark ignition engine.
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A battery electric vehicle could not meet the required range target of 320 km while keeping the vehicle weight below …
Lattice Boltzmann Method And Cellular Automata Simulation Of Particle Motion And Deposition In 2-D Case, Yichao Deng
Lattice Boltzmann Method And Cellular Automata Simulation Of Particle Motion And Deposition In 2-D Case, Yichao Deng
Dissertations, Master's Theses and Master's Reports - Open
This technical report discusses the application of the Lattice Boltzmann Method (LBM) and Cellular Automata (CA) simulation in fluid flow and particle deposition. The current work focuses on incompressible flow simulation passing cylinders, in which we incorporate the LBM D2Q9 and CA techniques to simulate the fluid flow and particle loading respectively. For the LBM part, the theories of boundary conditions are studied and verified using the Poiseuille flow test. For the CA part, several models regarding simulation of particles are explained. And a new Digital Differential Analyzer (DDA) algorithm is introduced to simulate particle motion in the Boolean model. …
A Novel Method For Prediction Of Mobile Robot Maneuvering Spaces, Patrick N. Currier, Alfred L. Wicks
A Novel Method For Prediction Of Mobile Robot Maneuvering Spaces, Patrick N. Currier, Alfred L. Wicks
Mechanical Engineering - Daytona Beach
As the operational uses of mobile robots continue to expand, it becomes useful to be able to predict the admissible maneuvering space to prevent the robot from executing unsafe maneuvers. A novel method is proposed to address this need by using force-moment diagrams to characterize the robot’s maneuvering space in terms of path curvature and curvature rate. Using the proposed superposition techniques, these diagrams can then be transformed in real-time to provide a representation of the permissible maneuvering space while allowing for changes in the robot’s loading and terrain conditions. Simulation results indicate that the technique can be applied to …
A Novel Resistance Exercise Machine For Use In A Lower Body Negative Pressure Box To Counteract The Effects Of Weightlessness, Christine M. Dailey
A Novel Resistance Exercise Machine For Use In A Lower Body Negative Pressure Box To Counteract The Effects Of Weightlessness, Christine M. Dailey
Doctoral Dissertations and Master's Theses
Physiological deconditioning is a critical problem in space, especially during long-term missions. Resistance exercise coupled with lower body negative pressure (LBNP) has been shown to be effective in counteracting some of the deconditioning related problems. This thesis describes the development of a compact and effective resistance exercise machine that works within an existing environmentally controlled LBNP Box and is designed to simulate both exercise and sitting, to prevent microgravity-induced deconditioning by simulating physiological and biomechanical features of upright exercise and daily activities. Theoretical calculations are carried out to determine whether kinematics, musculoskeletal loadings, and metabolic rate during supine exercise within …
Developing Defect-Tolerant Demolding Process In Nanoimprint Lithography, Alborz Amirsadeghi
Developing Defect-Tolerant Demolding Process In Nanoimprint Lithography, Alborz Amirsadeghi
LSU Doctoral Dissertations
Demolding, the process to separate stamp from molded resist, is most critical to the success of ultraviolet nanoimprint lithography (UV-NIL). In the present study we first investigated adhesion and demolding force in UV-NIL for different compositions of a model UV-curable resist containing a base (either tripropyleneglycol diacrylate with shorter chain length or polypropyleneglycol diacrylate with longer chain length), a cross-linking agent (trimethylolpropane triacrylate) and a photoinitiator (Irgacure 651). The demolding force was measured using a tensile test machine after imprinting the UV resist on a silicon stamp. In general, the shorter monomer shows a larger demolding force. Decreasing the cross-linking …
Numerical Modeling Of Heat Transfer And Fluid Flow In Laser Metal Deposition By Powder Injection, Zhiqiang Fan
Numerical Modeling Of Heat Transfer And Fluid Flow In Laser Metal Deposition By Powder Injection, Zhiqiang Fan
Doctoral Dissertations
"Laser metal deposition is an additive manufacturing technique which allows quick fabrication of fully-dense metallic components directly from Computer Aided Design (CAD) solid models. A self-consistent three-dimensional model was developed for the laser metal deposition process by powder injection, which simulates heat transfer, phase changes, and fluid flow in the melt pool, The governing equations for solid, liquid and gas phases in the calculation domain have been formulated using the continuum model. The free surface in the melt pool has been tracked by the Volume of Fluid (VOF) method, while the VOF transport equation was solved using the Piecewise Linear …
Approximate Dynamic Programming Based Solutions For Fixed-Final-Time Optimal Control And Optimal Switching, Ali Heydari
Approximate Dynamic Programming Based Solutions For Fixed-Final-Time Optimal Control And Optimal Switching, Ali Heydari
Doctoral Dissertations
"Optimal solutions with neural networks (NN) based on an approximate dynamic programming (ADP) framework for new classes of engineering and non-engineering problems and associated difficulties and challenges are investigated in this dissertation. In the enclosed eight papers, the ADP framework is utilized for solving fixed-final-time problems (also called terminal control problems) and problems with switching nature. An ADP based algorithm is proposed in Paper 1 for solving fixed-final-time problems with soft terminal constraint, in which, a single neural network with a single set of weights is utilized. Paper 2 investigates fixed-final-time problems with hard terminal constraints. The optimality analysis of …
Bio-Inspired Design, Fabrication And Testing Of Bipolar Plates For Pem Fuel Cells, Nannan Guo
Bio-Inspired Design, Fabrication And Testing Of Bipolar Plates For Pem Fuel Cells, Nannan Guo
Doctoral Dissertations
"The flow field of a bipolar plate distributes reactants for polymer electrolyte membrane (PEM) fuel cells and removes the produced water from the fuel cells. It greatly influences the performance of fuel cells, especially the concentration losses. Two approaches were developed to improve flow field designs in this dissertation. One is inspired by the biological circulatory structures and called bio-inspired designs, which have great potential to transport reactant efficiently and hence improve fuel cell performance. Another way is using a network-based optimization model to optimize the conventional flow field configurations, i.e., pin-type, parallel and serpentine designs, to improve flow distributions …
Measurement Of Continuum Breakdown Using A Disc Spin-Down Experiment In Low Pressure Air, Tathagata Acharya
Measurement Of Continuum Breakdown Using A Disc Spin-Down Experiment In Low Pressure Air, Tathagata Acharya
LSU Doctoral Dissertations
As flow becomes rarefied, a quantity called as the tangential momentum accommodation coefficient (TMAC) becomes important because it is a measure of the momentum transport from a gas molecule to a surface. Very few experimental measurements of continuum breakdown in boundary layer flows exist. All experimental measurements of the TMAC in macro-scale boundary layer flows have been done in the continuum slip and the transition flow regimes. Moreover the experimental apparatus used by previous researchers cannot accommodate for materials that are planar by nature such as those used in the field of aerospace and microfabrication. The objectives of this research …
Multiscale Analysis Of Contact In Smooth And Rough Surfaces: Contact Characteristics And Tribo-Damage, Ali Beheshti
Multiscale Analysis Of Contact In Smooth And Rough Surfaces: Contact Characteristics And Tribo-Damage, Ali Beheshti
LSU Doctoral Dissertations
This dissertation is comprised of two major interrelated foci. The first focus is to investigate the effect of surface roughness on the behavior of dry contacting bodies through both deterministic and statistical approaches. In the current research, different statistical micro-contact models are employed together with the bulk deformation of the bounding solids to predict the characteristics of the dry rough line-contact and elliptical point-contact including the apparent pressure profile, contact dimensions and real area of contact. Further, based on the results of numerical simulations, useful relationships are provided for the contact characteristics. In addition, a robust approach for the deterministic …
Micro & Nano Scale Mechanical Testing And Assembly With Applications To Metal Based Microsystems, Ke Chen
Micro & Nano Scale Mechanical Testing And Assembly With Applications To Metal Based Microsystems, Ke Chen
LSU Doctoral Dissertations
Metal-based high-aspect-ratio microscale structures (HARMS) are fundamental building blocks for functional metallic micro devices. This dissertation focuses on addressing several problems in fabrication and assembly of metal based microchannel devices. First, the materials’ responses to mechanical deformation at micro & nano scales, namely the mechanical “size effect”, have been explored by molding single crystal Al with long rectangular diamond punches and long wedge shaped indenters. It is noticed that the contact pressure of rectangular punches pressed into single crystal Al strongly depends on the punch width, while that of long wedge shaped indenters depends on the included wedge angle. We …
Automated Extraction And Classification Of Time-Frequency Contours In Humpback Vocalizations, Hui Ou, Whitlow W.L. Au, Lisa M. Zurk, Marc O. Lammers
Automated Extraction And Classification Of Time-Frequency Contours In Humpback Vocalizations, Hui Ou, Whitlow W.L. Au, Lisa M. Zurk, Marc O. Lammers
Electrical and Computer Engineering Faculty Publications and Presentations
A time-frequency contour extraction and classification algorithm was created to analyze humpback whale vocalizations. The algorithm automatically extracted contours of whale vocalization units by searching for gray-level discontinuities in the spectrogram images. The unit-to-unit similarity was quantified by cross-correlating the contour lines. A library of distinctive humpback units was then generated by applying an unsupervised, cluster-based learning algorithm. The purpose of this study was to provide a fast and automated feature selection tool to describe the vocal signatures of animal groups. This approach could benefit a variety of applications such as species description, identification, and evolution of song structures. The …
Development Of Dynamic Thermal Performance Metrics For Eco-Roof Systems, Seth Sinclair Moody
Development Of Dynamic Thermal Performance Metrics For Eco-Roof Systems, Seth Sinclair Moody
Dissertations and Theses
In order to obtain credit for an eco-roof in building energy load calculations the steady state and time-varying thermal properties (thermal mass with evapotranspiration) must be fully understood. The following study presents results of experimentation and modeling in an effort to develop dynamic thermal mass performance metrics for eco-roof systems. The work is focused on understanding the thermal parameters (foliage & soil) of an eco-roof, further validation of the EnergyPlus Green Roof Module and development of a standardized metric for assessing the time-varying thermal benefits of eco-roof systems that can be applied across building types and climate zones. Eco-roof foliage, …
Generalizable Methods For Modeling Lumbar Spine Kinematics, Craig Joseph Simons
Generalizable Methods For Modeling Lumbar Spine Kinematics, Craig Joseph Simons
Electronic Theses and Dissertations
A more complete understanding of lumbar spine kinematics could improve diagnoses and treatment of low back pathologies and may advance the development of biomechanical models. Kinematics describes motion of the five lumbar vertebrae without consideration for the forces that cause the motion. Despite considerable attention from researchers and clinicians, lumbar spine kinematics are not fully understood because the anatomy is not accessible for direct observation and the complex governing biomechanics produce small magnitude, coupled intervertebral movements.
The overall goal of this project was to develop a descriptive model of intervertebral lumbar spine kinematics that is applicable to a generalizable subject …
Modeling Ultrasonic Field Emanating From Scanning Acoustic Microscope For Reliable Characterization Of Pathogens (Biological Materials), Rowshan Ara Rima
Modeling Ultrasonic Field Emanating From Scanning Acoustic Microscope For Reliable Characterization Of Pathogens (Biological Materials), Rowshan Ara Rima
Theses and Dissertations
Acoustic microscopy provides extraordinary advantages over state-of-the-art invasive imaging techniques to determine the mechanical properties of living colonies of pathogens and micro-organisms. It is possible to obtain the morphomechanical parameters of the pathogenic colonies e.g. variation of thickness, stiffness and the coefficients of attenuation, using scanning acoustic microscope (SAM). However, the process requires an expert with extensive understanding of SAM and ultrasonic signals which is very time consuming and expensive for complex form of analysis. Due to lack of a suitable computational tool, presently the ultrasonic wave scattering, reflection and transmission through the biological specimens cannot be properly visualized. Without …
Dual-Phase Mixed Ion And Electron Conducting Co2-Selective Permeation Membranes, Lingling Zhang
Dual-Phase Mixed Ion And Electron Conducting Co2-Selective Permeation Membranes, Lingling Zhang
Theses and Dissertations
Fossil fuels are the dominant energy source powering our modern society. However, burning fossil fuels emits carbon dioxide (CO2), a greenhouse gas that can cause climate change and ultimately threaten the survival of humanity. Effectively mitigating CO2 emissions from the use of fossil fuels has become an intense subject of scientific research as well as political debate in recent years. The current mainstream technical approach to achieving that goal is to curb the emission of CO2 by capturing CO2 at point-sources and geologically storing it. The CO2 separation and capture process, the first step toward the ultimate storage of CO2, …
A New Class Of Solid Oxide Metal-Air Redox Batteries For Advanced Stationary Energy Storage, Xuan Zhao
A New Class Of Solid Oxide Metal-Air Redox Batteries For Advanced Stationary Energy Storage, Xuan Zhao
Theses and Dissertations
Cost-effective and large-scale energy storage technologies are a key enabler of grid modernization. Among energy storage technologies currently being researched, developed and deployed, rechargeable batteries are unique and important that can offer a myriad of advantages over the conventional large scale siting- and geography- constrained pumped-hydro and compressed-air energy storage systems. However, current rechargeable batteries still need many breakthroughs in material optimization and system design to become commercially viable for stationary energy storage.
This PhD research project investigates the energy storage characteristics of a new class of rechargeable solid oxide metal-air redox batteries (SOMARBs) that combines a regenerative solid oxide …
Environmental Effects On Mechanical And Thermal Behaviors Of Zinc Oxide Nanobelts And Dispersion Of Carbon Nanostructures, Yingchao Yang
Environmental Effects On Mechanical And Thermal Behaviors Of Zinc Oxide Nanobelts And Dispersion Of Carbon Nanostructures, Yingchao Yang
Theses and Dissertations
One-dimensional (1-D) nanostructures, such as nanowires, nanobelts, and nanotubes of different materials, have significant applications as nanoscale interconnects and active/functional components of electronic and optoelectronic devices, sensors, actuators, nanoelectromechanical systems (NEMS), and energy generation/conversion systems. The thermal and mechanical stabilities of those nanodevices and nanoenabled energy systems are of both theoretical and practical interests. Thermodynamic properties of nanomaterials are different from those of bulk materials. As the size of a solid particle reduces to the nanometer scale, the surface-to-volume ratio increases and the melting temperature may remarkably decrease. The functionality and/or reliability of those nanodevices and nanoenabled energy systems are …
Structural Health Monitoring Of Composite Laminates Using Piezoelectric And Fiber Optics Sensors, Catalin Roman
Structural Health Monitoring Of Composite Laminates Using Piezoelectric And Fiber Optics Sensors, Catalin Roman
Theses and Dissertations
This research proposes a new approach to structural health monitoring (SHM) for composite laminates using piezoelectric wafer active sensors (PWAS) and fiber optic bragg grating sensors (FBG). One major focus of this research was directed towards extending the theory of laminates to composite beams by combining the global matrix method (GMM) with the stiffness transfer matrix method (STMM). The STMM approach, developed by Rokhlin et al (2002), is unconditionally stable and is more computationally efficient than the transfer matrix method (TMM). Starting from theory, we developed different configurations for composite beams and validated the results from the developed analytical method …
Multi-Physicochemical Modeling Of Solid Oxide Fuel Cells And Electrolyzer Cells, Yuanyuan Xie
Multi-Physicochemical Modeling Of Solid Oxide Fuel Cells And Electrolyzer Cells, Yuanyuan Xie
Theses and Dissertations
Multi-physicochemical models are developed for solid oxide fuel cells and electrolysis cells. The models describe the complicated transport processes of charge (electron/ion) conservation, mass/species conservation, momentum conservation, and energy conservation. Transport processes are coherently coupled with chemical reforming processes, surface elementary reaction processes, as well as electro-oxidation processes of both hydrogen and carbon monoxide. The models are validated with experimental data and utilized for fundamental mechanism studies of SOFCs fueled with different type of fuels, such as hydrogen, hydrocarbon, e.g., methane, H2S, and their mixtures. The fundamental mechanisms associated with syngas generation using electrolysis cell are also extensively investigated using …
Welding Parameters, Distortion And Mechanical Properties Of Aa7075 Lap Joints In Ssfsw, Hejun Yu
Welding Parameters, Distortion And Mechanical Properties Of Aa7075 Lap Joints In Ssfsw, Hejun Yu
Theses and Dissertations
Friction Stir Welding (FSW), first invented by The Welding Institute of UK (TWI) in 1991, is a solid state welding process which was initially applied to welding Aluminum Alloy. FSW has wide application in industrial sectors. Stationary shoulder friction stir welding (SSFSW) was first developed to weld low thermal conductivity Ti-based alloys, which are hard to weld using conventional friction stir welding. Previous literatures showed SSFSW can produce uniform temperature distribution through thickness during the welding process. Since SSFSW is still under study phase, its advantages and disadvantages are not yet well defined. It is important to study the characteristics …