Mechanical Engineering Commons^™

Rheological Properties Of Two Stainless Steel 316l Powders For Additive Manufacturing, Haijun Gong, Xiaodong Xing, Hengfeng Gu

Manufacturing Engineering: Faculty Publications (2015-2023)

This study measures the rheological properties of two stainless steel 316L powders which are used for the powder-bed-fusion based additive manufacturing process. The purpose is to evaluate the newly acquired powder in comparison with the used and recycled powder, so that both powders can be mixed with each other to supplement the powder usage. The powder rheology properties, such as dynamic property, bulk property, and shear property, are tested and compared. The results and analysis confirm the compatibility of powder mixing.

Hydrogen Fuel Cell Gasket Handling And Sorting With Machine Vision Integrated Dual Arm Robot, Devin C. Fowler

College of Graduate Studies: Theses & Dissertations

Recently demonstrated robotic assembling technologies for fuel cell stacks used fuel cell components manually pre-arranged in stacks (presenters), all oriented in the same position. Identifying the original orientation of fuel cell components and loading them in stacks for a subsequent automated assembly process is a difficult, repetitive work cycle which if done manually, deceives the advantages offered by automated fabrication technologies of fuel cell components and by robotic assembly processes. We present an innovative robotic technology which enables the integration of automated fabrication processes of fuel cell components with robotic assembly of fuel cell stacks into a fully automated fuel …

Blade Design And Analysis Of Horizontal-Axis Wind Turbine: Cfd And Experimental Investigation Of Blades Design, Relwinde Fabrice Zongo

College of Graduate Studies: Theses & Dissertations

The present thesis focuses on the investigations of the computational fluid dynamics analysis and the experimental study of small scales Horizontal Axis Wind Turbine (HAWT) blades. The initial steps are taken; in the process of this research were the selection of the airfoil type to be used in each blade design and the creation of a blade design with high efficiency operating in a low wind speed zone. For the mentioned blade design process, the following airfoils were selected respectively NACA 0010, NACA 0012, NACA 1412, NACA 2412, NACA 2414, NACA 4412 and NACA 6412. This selection intends to provide …

Energy And Exergy Analysis Of A Thermosiphon And Forced-Circulation Flat-Plate Solar Collector Using Mwcnt/Water Nanofluid, Mahmoud Eltaweel, Ahmed A. Abdel-Rehim

Mechanical Engineering

The scientific community has focused on the use of nanofluids to enhance solar collectors' thermal efficiency. Solar energy is considered an extensively available energy resource with a weak effect on the environment. The flat-plate solar collector is considered to be the most common collector used, but the efficiency of the collector has limitations, such as the low effectiveness of the absorber in terms of energy absorption and the transmission of that energy to the working fluid. The flat-plate solar collector can be enhanced by replacing the working fluid with a nanofluid. Nanofluids are considered new media that exhibit thermophysical properties …

Energy Lesson Design, Jessica Lyons

ENgaging Educators in Renewable enerGY (ENERGY): Lesson Plans & Slideshows (2017-2019)

No abstract provided.

Solar Tracker Renewable Energy, Stephanie Christie, Annabeth Helmly, Matthew Smith, Katrina Vaughan

ENgaging Educators in Renewable enerGY (ENERGY): Lesson Plans & Slideshows (2017-2019)

No abstract provided.

Analysis Of Horizontal Axis Wind Turbine Array Optimization, Peter-Claver Nwanze, Keith Bazemore, Jessica Lyons, J. Ann Mitchem

ENgaging Educators in Renewable enerGY (ENERGY): Lesson Plans & Slideshows (2017-2019)

Wind energy is the fastest growing form of renewable energy, with a multitude of possibilities for expansion. This, as well as other forms of renewable energy, will facilitate understanding of the growing concerns regarding global warming by decreasing our dependence on fossil fuels. Wind energy requires wind speeds of at least six miles per hour; therefore, only certain geographical areas are suitable for the use of this technology. The purpose of this experiment was to determine whether the orientation of an array of wind turbines increases or decreases energy production and efficiency. In this study, various arrays consisting of five …

Design, Fabrication, And Characterization Of Functionally Graded Materials, Sreekar Karnati

Doctoral Dissertations

“The aim of this research was to investigate the feasibility of fabricating custom designed, graded materials using Laser Metal Deposition (LMD) that will cater for functionality and unconventional repair. The ultimate goal of the project is to establish the versatility of LMD for fabricating advanced materials and tackling problems that have been conventionally difficult or in cases infeasible. In order to accomplish these goals, this research involved investigations into, the feasibility of using elemental powders as modular feedstocks, the feasibility of fabricating tailored gradients with these custom compositions, and finally leveraging the advantages of grading materials using LMD to successfully …

Cmas/Volcanic Ash Infiltration Performance Of Yttria Rich-Zirconia Thermal Barrier Coatings Produced By Electron Beam Physical Vapor Deposition, Juan Jose Gomez Chavez

Open Access Theses & Dissertations

For many years the use of thermal barrier coatings (TBC) in gas turbine engines has allowed a significant increase in engine operating temperatures which are above the Ni-based super alloys' melting point. The base material for TBCs is the state of the art 7 wt % yttria stabilized zirconia (YSZ) which provides the thermal protection. Current industry demands for increased engine efficiency has pushed TBCs to the limits where significant technological constrains have been identified. One of the main ones represents the high temperature corrosion of the TBC material due to the ingestion of silicate based airborne particles commonly referred …

Small Satellite Development At Utep, Emily Herzog

Open Access Theses & Dissertations

The small satellite industry has seen tremendous growth in recent years. A CubeSat is a particular type of standardized small satellite that follows the CubeSat specifications. These specifications define the structural, testing, and operational requirements of the satellite. This standard facilitates cheaper design, integration, and launch of satellites, allowing smaller organizations to participate in the normally costly area of space exploration.

The University of Texas at El Paso has recognized the opportunity and has begun developing several CubeSats. The two that are the topic of this Thesis are called Orbital Factory II (OFII) and Orbital Factory X (OFX). An on-orbit …

Pressureless Sintering Of Zirconium Diboride Obtained By Combustion Synthesis, Gabriel Llausas

Open Access Theses & Dissertations

Magnetohydrodynamic (MHD) direct power generation has the potential to significantly increase the thermal efficiency of coal fired power plants. Materials for MHD electrodes should have high melting points, high electrical and thermal conductivities, and excellent thermal shock and corrosion resistance. Zirconium diboride (ZrB2), which belongs to the class of ultra-high temperature ceramics (UHTC), is a promising material for this application. Mechanically activated self-propagating high-temperature synThesis (MASHS) is an attractive method for its fabrication. Previous studies have shown that zirconium diboride can be fabricated from inexpensive oxides of zirconium and boron (ZrO2 and B2O3) using magnesium as a reducing agent and …

Compressive And Rheological Deformation Analysis Of Large Area Pellet-Fed Material Extrusion 3d Printed Parts In Relation To In Situ Thermal Imaging, Eduardo Meraz Trejo

Open Access Theses & Dissertations

In large area pellet extrusion additive manufacturing, the temperature of the substrate just prior to the deposition of a new subsequent layer has an effect on the overall structure of the part. Warping and cracking occur if the substrate temperature is below a specific threshold, but also deformation and deposition adhesion failure occur if the substrate temperature is above a certain threshold just prior to deposition of a new layer. Currently, Big Area Additive Manufacturing (BAAM) machine users mitigate this problem by trial and error, which is costly and may result in decreased mechanical properties, monetary losses and time inefficiencies. …

Additive Manufactured Ear Pinna For Spatial Cue Preservation In Custom Hearing Devices, Carlos Felipe Acosta Carrasco

Open Access Theses & Dissertations

Advancements in additive manufacturing/3D printing technologies has permitted the fabrication of intricate features such as the ones present in the human ear. The outer ear, also known as the pinna, allows for the spectral cues from incoming sound to be captured and identified. The hypothesis of the preservation of auditory localization and externalization relies on the fabrication of an ear pinna via additive manufacturing embedded into a headset for spectral cue preservation and hearing protection. Before exploring these custom circumaural hearing devices, a study on the fabrication process of AM pinnae was performed. The KEMAR system for acoustic research was …

Structures And Daq System For The Lox/Lch4 500 And 2000 Lbf. Rocket Engines, Rachel Pilgrim

Open Access Theses & Dissertations

With the progression of space exploration and research, new alternative fuels and fuel combinations have been discovered. The ability to produce methane from Mars' atmosphere and oxygen from Mars' regolith has led to the two becoming a great alternative propellant combination for rocket propulsion systems. To further advance LOX/LCH4 propulsion systems, a 500 and 2000 lbf rocket engine were designed and manufactured and are to be launched from the MIRO cSETR Technology Research and Innovation Acceleration Park (tRIAc) in Fabens, Texas for data collection and analysis. The objective of this thesis is to give a thorough overview of the static …

Cradle To Grave Lifecycle Process Analysis For Transuranic Waste Management Los Alamos National Laboratory, Cesar Enrique Dominguez

Open Access Theses & Dissertations

Amid World War II, in the late 1930s, nuclear fission was discovered. This revolution gave way to the development of nuclear technologies, including the world's first atomic bomb; these advancements in nuclear research left behind radioactive waste. Radioactive waste is known as the byproduct of nuclear reactors, fuel processing plants, hospitals, nuclear research facilities, as well as the result from the decommissioning and dismantling of radiation-exposed buildings and materials. This byproduct may be dangerous to workers, the public, and the environment and must, therefore, be handled with utmost safety. Given this, radioactive waste must be processed, stored, and disposed of …

Development Of An Iridium-Ceramic Substrate Catalyst Bed For The Decomposition Of Ionic Green Liquid Monopropellants, Alejandro Andre Vazquez

Open Access Theses & Dissertations

In an effort to advance green monopropellant propulsion using ionic liquids, the Center for Space Exploration and Technology Research (cSETR) has developed a pellet based catalyst bed for the decomposition of AF-M315E. The present paper will go over some of the fundamental research conducted towards the development of a catalyst bed and some of its applications. Three different catalyst bed designs were produced where each uses a different ceramic substrate material. The three different substrates are aluminum oxide, tungstated zirconia, silicon carbide each coated with iridium as the catalyst material. An experimental setup for testing the catalytic decomposition AF-M315E was …

Thermal Characterization Of Abs/Carbon Fiber, Abs/ Glass Fiber And Petg/Glass Fiber Reinforced Composites Used In Large Area Additive Manufacturing, Fernando Adrian Rodriguez Lorenzana

Open Access Theses & Dissertations

Additive manufacturing has seen continuous advancements, such as the inclusion of large-area additive manufacturing extrusion systems. These systems precede small-scale 3D printing by means of research and technological development for the manufacturing of plastic and fiber industries. Big Area Additive Manufacturing (BAAM), a material extrusion process, is capable of 3D printing large parts using thermoplastic composites by adding fiber reinforcements. The incorporation of fibrous materials, carbon fiber (CF) or glass fiber (GF), is a common practice in which percentage nominal ratios of fiber reinforcement by weight are implemented to the polymer matrix. In general, this enables warpage reduction during printing, …

Cfd Dem Analysis Of A Dry Powder Inhaler, Antara Badhan

Open Access Theses & Dissertations

Dry powder inhalers (DPIs), used as a means for pulmonary drug delivery, typically contains a combination of an Active Pharmaceutical Ingredient (API) and significantly larger carrier particles. The micro-sized drug particles - which have a strong propensity to aggregate and a poor aerosolization performance - are mixed with significantly large carrier particles that are unable to penetrate the mouth-throat region to deagglomerate and entrain the smaller API particles in the inhaled airflow. The performance of a DPI, therefore, depends on entrainment the carrier-API combination particles and the time and thoroughness of the deagglomeration of the individual API particles from the …

Numerical Investigation Of Molten Metal Infiltration And Pillared Cooling Systems At Microscale, Shaikh Tanveer Tanveer Hossain

Open Access Theses & Dissertations

Flow-through porous media at pore-scales is one of the less explored sides of fluid mechanics due to the complexity associated with highly irregular pore geometry. Most of the established methods that try to quantify such flow are based on statistical observations of flow through numerous porous specimens. Such understandings may satisfy the need for applications where micro-level details are not a concern. Some numerical approaches did try to analyze the micro-level flow, but the analysis was confined to small sample sizes due to the intensive computation challenge. There are several applications of porous media flow where analyzing the large-scale flow …

Investigating Using Titanium Zirconium Molybdenum For Additively Manufacturing Aerospace Components, Justin Hunter Vanhoose

Open Access Theses & Dissertations

Mankind throughout history has possessed an innate characteristic to explore, migrating to new frontiers.The requirement for this travel is most broadly associated with the need to pursue more resources. Rockets have been used as a means of weapons since the Sung Dynasty in the thirteenth empire and have now been integrated for travel/transport. The sophistication of rocketry and propulsion has reached a level to where it is plausible that mankind will be a multi-planetary species. The space industry has grown significantly with the advancement of the sophistication of these rocket technologies. However, a specific challenge to overcome in the space …

Sediment Patterns From Fluid-Bed Interactions: A Direct Numerical Simulations Study On Fluvial Turbulent Flows, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications

We present results on the initial formation of ripples from an initially flattened erodible bed. We use direct numerical simulations (DNS) of turbulent open channel flow over a fixed sinusoidal bed coupled with hydrodynamic stability analysis. We use the direct forcing immersed boundary method to account for the presence of the sediment bed. The resolved flow provides the bed shear stress and consequently the sediment transport rate, which is needed in the stability analysis of the Exner equation. The approach is different from traditional linear stability analysis in the sense that the phase lag between the bed topology, and the …

Nurturing Brilliance In Engineering: Creating Research Venues For Undergraduate Underrepresented Minorites In Engineering As An Initiative From Faculty Members That Foster Academic Inclusion, Development, And Postgraduation Instruction, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

In this study, a new model for attracting, advancing, and advocating for the participation of underrepresented minorities in research venues is proposed with the intention of fostering academic inclusion, development, and post-graduation mentorship. It involves developing and nurturing a disposition from faculty by proactively identifying students via classroom interaction, performance, and academic aptitude and extending a personal invitation to collaborate on the research team. Current research opportunities for engineering undergraduates at tier-one institutions are obtained by students' incentive to communicate with faculty members via email or office hours. Despite the available opportunities, only a limited number of students are selected …

The Educational Value Of Modelling Complex Thermodynamic Systems With System Dynamics Software, Stephen Crown, Constantine Tarawneh

Mechanical Engineering Faculty Publications

The solution of problems involving complex thermodynamic systems often occupies much of a students' time and can be a distraction from them developing a clear understanding of system components, interaction of subsystems, modelling simplifications and assumptions, and design optimization. Refocusing students on the fundamental concepts of thermal systems design and analysis is possible with the introduction of system modelling software that carries some of the load of repetitive calculation required for complex systems. Models of thermodynamic systems encountered in an advanced undergraduate thermodynamics course were developed by students (some provided to students) to solve homework problems of complex steam power …

Simulation Of Droplet Impacting A Square Solid Obstacle In Microchannel With Different Wettability By Using High Density Ratio Pseudopotential Multiplerelaxation- Time (Mrt) Lattice Boltzmann Method (Lbm), Wandong Zhao, Ying Zhang, Wenqiang Shang, Zhaotai Wang, Ben Xu, Shuisheng Jiang

Mechanical Engineering Faculty Publications

In this paper, a pseudopotential high density ratio (DR) lattice Boltzmann Model was developed by incorporating multi-relaxation-time (MRT) collision matrix, large DR external force term, surface tension adjustment external force term and solid-liquid pseudopotential force. It was found that the improved model can precisely capture the two-phase interface at high DR. Besides, the effects of initial Reynolds number, Weber number, solid wall contact angle (CA), ratio of obstacle size to droplet diameter ( 1 χ ), ratio of channel width to droplet diameter ( 2 χ ) on the deformation and breakup of droplet when impacting on a square obstacle …

In Situ Selective Nitriding Using An Open Source Laser Powder Bed Fusion System, Andres Gerardo Navarro

Open Access Theses & Dissertations

Conventional forms of nitriding titanium limit the locations to surfaces, limiting applications to simple coatings. Additive manufacturing methods provide the opportunity for surface coating methods to be utilized in a layer by layer fabrication method and increase the uses of nitrides. Laser powder bed fusion (LPBF) in particular, provides a fabrication environment with sufficient energy to allow for material nitriding as well as the flexibility of being able to utilize a variety of materials and shielding gases for processing. This project utilizes an AconityONE open source LPBF system with custom laser parameter settings to fabricate and nitride Ti-6Al-4V substrates. This …

Development Of Actuators Using Material Extrusion Additive Manufacturing With Embedded Shape Memory Alloy Wire, Alfonso Fernandez

Open Access Theses & Dissertations

Over the past several decades, the advancements in Additive Manufacturing (AM) technologies have opened a wide variety of applications where AM can be used. Some examples of these advancements are the introduction of automatic wire embedding capabilities, the introduction of multi-material processing and the printing of thermoplastic elastomers. With the availability of these advancements, it is now possible to create spark-free, dust-free actuation mechanisms for applications where it is crucial that no spark is generated (i.e. space shuttle fuel valve).

In this research, a Lulzbot TAZ 6 desktop material extrusion system was utilized to print parts out of Plasticized Copolymer …

A Modified Wilshire Model For Creep Deformation And Damage Prediction, Jaime Aaron Cano

Open Access Theses & Dissertations

In this work, a new constitutive model, the WCS model, is derived that combines the Wilshire equations with continuum damage mechanics (CDM) for the long-term prediction of creep deformation, damage, and rupture. Long-term creep data is expensive and time-consuming to obtain because conventional creep testing is real-time. There is a need to extrapolate long-term creep behaviors from short-term data. Models that can accurately predict long-term creep behavior over a wide range of boundary conditions are vital for design engineers. The classic Wilshire equations can accurately extrapolate the long-term stress-rupture, minimum-creep-strain-rate, and time-to-strain of various alloys as their functional form has …

Development Of An Ionic Green Monopropellant 1 Newton Thruster For Small Satellite Application, Jaclyn Mona Mejia

Open Access Theses & Dissertations

In effort to advance green monopropellant propulsion using AF-M315E, a 1N thruster was developed to demonstrate the propellant capabilities for low thrust requirement missions. The current study presents the development of a 1 Newton thruster. The thruster was designed based on available literature for initial parameters. In house developed catalyst was packed into the 1 Newton thruster, and mounted onto a thrust stand for testing. Two configurations of catalyst were used for this testing campaign. As a result, temperature peaks from AF-M315E decomposition gases reached up to 1400°C with an iridium loading factor of 25% by mass with both catalyst …

Direct Write 3d Printing Of Functional Ceramics, Jorge Angel Diaz

Open Access Theses & Dissertations

Humidity sensors are used in many industries and are important for ensuring quality and safety. Ceramic sensors are preferred because of their quick response time, ability to withstand high temperatures and excellent Chemical and mechanical stability. The manufacturing world has been moving toward additive manufacturing which is a form of synthesizing 3D tangible layer by layer in witch minimal waste is produced. Additive manufacturing also is known as 3D printing has opened new possibilities to design engineers by giving them design freedom and access to the layers of a part to allow embedded sensors. There is a category of ceramics …

Materials Characterization In The Development Of Combustion-Based Methods For Synthesis Of Niobium Silicides, Edgar Maguregui

Open Access Theses & Dissertations

The use of characterization techniques is essential for a better understanding of novel manufacturing processes and for investigating how the process parameters affect the products. Mechanically activated self-propagating high-temperature synthesis (MASHS) is an attractive method for the production of high-temperature structural materials. In the present work, it was used to fabricate Nb5Si3 compound and Nb5Si3/Nb composites. It has been shown that for mechanical activation of Nb/Si mixtures, a planetary ball mill is more effective than a shaker ball mill used in prior research on MASHS of Nb5Si3. The influence of mixture composition and experimental parameters, such as milling time and …