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Simulation Of Different Rib Shapes In Square Channel, Md Sahedul Islam 2018 South Dakota State University

Simulation Of Different Rib Shapes In Square Channel, Md Sahedul Islam

Electronic Theses and Dissertations

This study investigates heat transfer and pressure drop for rib-roughened square channel without bleed. To optimize the shape of rib, CFD tools were used to model and simulate channel flow with a variety of rib angles and geometries. To validate simulations and determine the turbulence model, experimental results for two-pass channels with ribs at 45˚ angles with BR = 0 and Re = 25,000 was compared. It was found after conducting simulations with different turbulence models that SST turbulence model gave the best results.


Effect Of Poisson’S Ratio On Young's Modulus Characterization Using Ultrasonic Technique By Modeling, Michael Onyetube 2018 South Dakota State University

Effect Of Poisson’S Ratio On Young's Modulus Characterization Using Ultrasonic Technique By Modeling, Michael Onyetube

Electronic Theses and Dissertations

The past 27 years has witnessed a revolutionary growth in the progress of material development and application in almost all industry and business sectors, and this seems to be continuing even today. So many material-driven innovations have enabled the global spread in technology and improvements in capability, ranging from communications to aerospace and healthcare, to automotive and agriculture. Mechanical behavior of elastic materials is modeled by two main independent constants; Young’s modulus and Poisson’s ratio. An accurate measurement of both constants is necessary in most engineering applications, for example, the standard materials used for the calibration of some equipment, quality …


Development Of Material For 3d Printed Habitats With Extraplanetary Applications, Taylor Wait 2018 South Dkaota State University

Development Of Material For 3d Printed Habitats With Extraplanetary Applications, Taylor Wait

Electronic Theses and Dissertations

3D printing, also called Additive Manufacturing, has increasingly become a focus for research because of the potential to replace complicated assemblies or complex parts with a single printed item. The space industry is very interesting in studying 3d printing with parts being tested and used on rockets, a 3D printer being installed at the International Space Station and is being developed for use in manned exploration of extraplanetary bodies to build habitats. To encourage teams from around the world to develop technologies and materials for autonomous habitat construction using minimal Earth exports, NASA created the 3D Printed Habitat Challenge. NASA …


Simulation Of Gas Dynamic Cold Spray Process, Sai Rajkumar Vadla 2018 South Dakota State University

Simulation Of Gas Dynamic Cold Spray Process, Sai Rajkumar Vadla

Electronic Theses and Dissertations

The utilization of computational fluid dynamics (CFD) as a study tool in the aerodynamics and turbomachinery industry reinforces efficiency in the design of aircraft or for understanding the flow through pipes. CFD offer tools to model different geometries and perform a more extensive study of the flow phenomena. This gives the opportunity to model a variety of geometries and analyze their behavior under different operating conditions. A similar approach can be applied to coating technologies. Coating technologies play an essential role in the manufacturing industry. Their ability to form layers of specific materials onto engineering components to enhance mechanical and …


Testing Of A 1n Af-M315e Thruster, Daniela Ivette Aguilar 2018 University of Texas at El Paso

Testing Of A 1n Af-M315e Thruster, Daniela Ivette Aguilar

Open Access Theses & Dissertations

The Center for Space Exploration and Technology Research (cSETR) at the University of Texas at El Paso (UTEP) is currently pursuing various space propulsion and small satellite projects. One of these projects is called Orbital Factory X (OFX), which mission is to design a 2U Cube-Satellite (Cube Sat) with 4 green mono-propellant thrusters along with multiple micro-cathode arc thrusters. A CubeSat is a small-scale version of a satellite that is usually placed in orbit for near earth missions. However, they have a relative short life and limited maneuverability due to their limited source of power and restricted payload. Now, technologies …


Combustion Joining Of Regolith Tiles For The Construction Of Launch And Landing Pads On The Moon And Mars, Robert Edwin Ferguson 2018 University of Texas at El Paso

Combustion Joining Of Regolith Tiles For The Construction Of Launch And Landing Pads On The Moon And Mars, Robert Edwin Ferguson

Open Access Theses & Dissertations

Combustion-based methods are attractive for space manufacturing because the use of chemical energy stored in reactants dramatically decreases the required external energy input. Recently, a sintering technique has been developed for converting lunar/Martian regolith into ceramic tiles, but it is unclear how to build a reliable launch/landing pad from these tiles with small amounts of energy and materials. Here the feasibility of joining regolith tiles using self-propagating high-temperature reactions between two metals powders is explored. Combustion of a 1:1 molar aluminum/nickel mixture placed in a gap between two tiles, made of JSC-1A lunar regolith simulant, was studied in an argon …


An Adaptive Creep Modeling Approach Using Metamodeling, Mohammad Shafinul Haque 2018 University of Texas at El Paso

An Adaptive Creep Modeling Approach Using Metamodeling, Mohammad Shafinul Haque

Open Access Theses & Dissertations

Recent drives to increase the efficiency of existing fossil energy power plants and the development of Advanced Ultrasupercritical power plants, have led to designs with steam pressures above 4000 psi and temperatures exceeding 1400°F. The complexity of the applied thermo-mechano chemical boundary conditions makes it critically important to consider creep and creep related failures. A primary concern to FE practitioners is the determination of which constitutive models are the "best", capable of reproducing the mechanisms expected in an intended design accurately; as well as what experimental data sets are proper or "best" to use for fitting the constitutive parameters needed …


Analysis Of Aluminum-Air Battery By Physics-Based Mathematical Model, Chong Zhou 2018 Northern Illinois University

Analysis Of Aluminum-Air Battery By Physics-Based Mathematical Model, Chong Zhou

Graduate Research Theses & Dissertations

The demand of electrical energy system is increasing rapidly these days for diverse applications from portable electronics and electrical vehicles to grid-scale energy storage. Lithium-ion battery has been utilized for most of those applications, but due to high cost (about $600/ kWh) and lower energy density (0.37 kWh/kg), the advent of low cost and high performing battery system is required. In this study, we will revisit aluminum-air battery as a promising system which has excellent features such as high energy density of 2.8 kWh/kg, low cost, and safe in nature, but it was abandoned due to challenging issues. One of …


Neuromuscular Reflex Control For Prostheses And Exoskeletons, Sandra K. Hnat 2018 Cleveland State University

Neuromuscular Reflex Control For Prostheses And Exoskeletons, Sandra K. Hnat

ETD Archive

Recent powered lower-limb prosthetic and orthotic (P/O) devices aim to restore legged mobility for persons with an amputation or spinal cord injury. Though various control strategies have been proposed for these devices, specifically finite-state impedance controllers, natural gait mechanics are not usually achieved. The goal of this project was to invent a biologically-inspired controller for powered P/O devices. We hypothesize that a more muscle-like actuation system, including spinal reflexes and vestibular feedback, can achieve able-bodied walking and also respond to outside perturbations. The outputs of the Virtual Muscle Reflex (VMR) controller are joint torque commands, sent to the electric motors …


Human Activity Tracking And Recognition Using Kinect Sensor, Roanna Lun 2018 Cleveland State University

Human Activity Tracking And Recognition Using Kinect Sensor, Roanna Lun

ETD Archive

The objective of this dissertation research is to use Kinect sensor, a motion sensing input device, to develop an integrated software system that can be used for tracking non-compliant activity postures of consented health-care workers for assisting the workers' compliance to best practices, allowing individualized gestures for privacy-aware user registration, movement recognition using rule-based algorithm, real-time feedback, and exercises data collection. The research work also includes developing a graphical user interface and data visualization program for illustrating statistical information for administrator, as well as utilizing cloud based database system used for data resource.


Non-Intrusive Optical Measurement Of Electron Temperature In Near Field Plume Of Hall Thruster, Peter J. Urban 2018 Cleveland State University

Non-Intrusive Optical Measurement Of Electron Temperature In Near Field Plume Of Hall Thruster, Peter J. Urban

ETD Archive

Currently there is a large interest in the use of more efficient means of propulsion in long term missions due to the costs and difficulties associated with placing and maintaining the needed fuel for conventional chemical systems in orbit. Mass reduction of upper stages will return large returns due to the great reduction in required lower stage fuel. Due to these factors, alternatives are undergoing active research, though this paper is concerned with the area of electrical propulsion. Electric propulsion is broadly defined as propulsion where the energization of the exhaust occurs via application of electromagnetic fields as opposed to …


Predictive Simulations Of Gait And Their Application In Prosthesis Design, Anne D. Koelewijin 2018 Cleveland State University

Predictive Simulations Of Gait And Their Application In Prosthesis Design, Anne D. Koelewijin

ETD Archive

Predictive simulations predict human gait by solving a trajectory optimization problem by minimizing energy expenditure. These simulations could predict the effect of a prosthesis on gait before its use. This dissertation has four aims, to show the application of predictive simulations in prosthesis design and to improve the quality of predictive simulations. Aim 1 was to explain joint moment asymmetry in the knee and hip in gait of persons with a transtibial amputation (TTA gait). Predictive simulations showed that an asymmetric gait required less effort. However, a small effort increase yielded a gait with increased joint moment symmetry and reduced …


Advanced Manufacturing Of Titanium Alloys For Biomedical Applications, Nicholas C. Mavros 2018 Cleveland State University

Advanced Manufacturing Of Titanium Alloys For Biomedical Applications, Nicholas C. Mavros

ETD Archive

In metallurgy, Titanium has been a staple for biomedical purposes. Its low toxicity and alloying versatility make it an attractive choice for medical applications. However, studies have shown the difference in elastic modulus between Titanium alloys (116 GPa) and human bone (40-60 GPa) contribute to long term issues with loose hardware fixation. Additionally, long term studies have shown elements such as Vanadium and Aluminum, which are commonly used in Ti-6Al-4V biomedical alloys, have been linked to neurodegenerative diseases like Alzheimers and Parkinsons. Alternative metals known to be less toxic are being explored as replacements for alloying elements in Titanium alloys. …


An Anisotropic Constitutive Model For Nuclear Grade Graphite, James Christopher 2018 Cleveland State University

An Anisotropic Constitutive Model For Nuclear Grade Graphite, James Christopher

ETD Archive

Graphite material is used extensively in nuclear reactors however the material has a limited strain range for elastic behavior. This provides the motivation to derive a constitutive model that captures the inelastic deformations exhibited by this material. This dissertation first presents details of an isotropic constitutive model derived using continuum principles of engineering mechanics that accounts for different inelastic behavior in tension and compression. An inelastic dissipation function was developed using an integrity basis proposed by Green and Mkrtichian (1977) for the isotropic version of the model. This isotropic model was then extended to capture anisotropic stress-strain behavior using directional …


Comparative Study Of The Microstructure And Mechanical Properties Of Mechanically Alloyed And Spark Plasma Sintered Alxcocrfeni (0≤X≤2)High Entropy Alloys, David Mikhail 2018 Cleveland State University

Comparative Study Of The Microstructure And Mechanical Properties Of Mechanically Alloyed And Spark Plasma Sintered Alxcocrfeni (0≤X≤2)High Entropy Alloys, David Mikhail

Undergraduate Research Posters 2018

High entropy alloys are a new class of material systems that have promising potential in high temperature structural applications. Mechanical alloying (MA) has gained special attention as a powerful non-equilibrium process for fabricating amorphous and nanocrystalline materials, whereas spark plasma sintering (SPS) is a unique technique for processing dense and near net shape bulk alloys with homogenous microstructure. This research paper discusses novel mechanically alloyed followed by spark plasma sintering approach for assessing composition-microstructure-microhardness relationship in AlxCoCrFeNi (0≤x≤2) high entropy alloy as a candidate system. With increasing Al content, there was a gradual change from a fcc-based microstructure to a …


Spark Plasma Sintering Of Soft Magnetic Materials, Harnavdeep Kaur, Taban Larimian, Javier Esquivel 2018 Cleveland State University

Spark Plasma Sintering Of Soft Magnetic Materials, Harnavdeep Kaur, Taban Larimian, Javier Esquivel

Undergraduate Research Posters 2018

Over the past 3 decades, iron-based soft magnetic alloys such as Finemet (Fe73.5Si13.5B9Nb3Cu1 (at%)) have attracted great interest due to their exceptional magnetic properties like high magnetization, low coercivity, and high curie temperature. However, the production of amorphous precursor requires very high cooling rates, and thus only wires, powders, and thin ribbons are achievable, yet these are not suitable in industrial applications where large volume of bulk magnetic components is required. Mechanical alloying (MA) has gained special attention as a powerful non-equilibrium process for fabricating amorphous and nanocrystalline materials, whereas spark plasma sintering (SPS) is a unique technique for processing …


Evaluation Of Wind Energy Forecasts: The Undervalued Importance Of Data Preparation, Gianni Goretti, Aidan Duffy 2018 Technological University Dublin

Evaluation Of Wind Energy Forecasts: The Undervalued Importance Of Data Preparation, Gianni Goretti, Aidan Duffy

Conference papers

The evaluation of wind energy forecasts is a key task for those involved in the wind power sector, and the accurate evaluation of forecasts is fundamental to make informed decisions both in business and research. To evaluate the accuracy of a forecast, observed values must be compared against forecast values over a test period. At times, however, the actual generation of a wind farm can be affected by factors that are outside the scope of the forecast model. Evaluating a forecast using a data set that includes such out-of-scope observations might give a biased or inconsistent assessment. In the data …


Task Complexity, And Operators’ Capabilities As Predictor Of Human Error: Modeling Framework And An Example Of Application, Maria Chiara Leva, Alberto Caimo, R. Duane, Micaela Demichela, Lorenzo Comberti 2018 Technological University Dublin

Task Complexity, And Operators’ Capabilities As Predictor Of Human Error: Modeling Framework And An Example Of Application, Maria Chiara Leva, Alberto Caimo, R. Duane, Micaela Demichela, Lorenzo Comberti

Conference Papers

This paper presents the initial framework adopted to assess human error in assembly tasks at a large manufacturing company in Ireland. The model to characterize and predict human error presented in this paper is linked conceptually to the model introduced by Rasch (1980), where the probability of a specified outcome is modelled as a logistic function of the difference between the person capacity and item difficulty. The model needs to be modified to take into account an outcome that is not dichotomous and feed into the interaction between two macro factors: (a) Task complexity: that sum-marises all factors contributing to …


Effect Of High- And Low-Molecular-Weight Hyaluronic-Acid-Functionalized-Az31 Mg And Ti Alloys On Proliferation And Differentiation Of Osteoblast Cells, Sankalp Agarwal, Brendan Duffy, James Curtin, Swarna Jaiswal 2018 Technological University Dublin

Effect Of High- And Low-Molecular-Weight Hyaluronic-Acid-Functionalized-Az31 Mg And Ti Alloys On Proliferation And Differentiation Of Osteoblast Cells, Sankalp Agarwal, Brendan Duffy, James Curtin, Swarna Jaiswal

Articles

The quality of patient care has increased dramatically in recent years because of the development of lightweight orthopedic metal implants. The success of these orthopedic implants may be compromised by impaired cytocompatibility and osteointegration. Biomimetic surface engineering of metal implants using biomacromolecules including hyaluronic acid (HA) has been used an effective approach to provide conditions favorable for the growth of bone forming cells. To date, there have been limited studies on osteoblasts functions in response to metal substrates modified with the hyaluronic acid of different molecular weight for orthopedic applications. In this study, we evaluated the osteoblasts functions such as …


Evaluating Augmented Reality For Space Telerobotics Training, John Karasinski 2018 Florida Institute of Technology

Evaluating Augmented Reality For Space Telerobotics Training, John Karasinski

Link Foundation Modeling, Simulation and Training Fellowship Reports

Despite the extensive previous research into manual tracking, to the author’s knowledge there exists no study in the literature addressing human performance or workload changes in manual tracking tasks between traditional computer monitors and mobile, augmented reality headsets. The aim of this study was to investigate the effect of several factors on human performance and workload in a three-axis manual tracking task. Recent advances in computing hardware have enabled a new generation of augmented reality stereoscopic devices, such as the Microsoft HoloLens, which have yet to be evaluated in the literature. The Microsoft HoloLens provides depth cues to the user …


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