Engineering Commons^™

Development Of A Solidworks Simulation Toolkit For A Sophomore Level Biomedical Engineering Course, Jordan Crosby

Biomedical Engineering Undergraduate Honors Theses

In the engineering industry, computer-aided design (CAD) programs are used to create models and create virtual experiments or studies that allow engineers to observe the real behavior of parts or assemblies under certain conditions. Companies hire students with experience in CAD, as professionals believe that CAD experience is beneficial [1,2]. SolidWorks is among the most popular CAD software used by engineers. SolidWorks has multiple functionalities that also allow for finite element analysis dependent on the license. Users can create simulation studies in SolidWorks Simulation that can be used as an accurate approximation for real results.

The goal of this study …

Development And Characterization Of Nanofiber-Based Thermoelectric And Piezoelectric Composites, Julio Enrique Trevino

Theses and Dissertations

This study focuses on the development and characterization of nanofiber-based composites with the goal of developing flexible, lightweight, and cost effective thermoelectric and piezoelectric devices. The following materials were used in the development of the composites: polyvinylidene fluoride (PVDF) with polyaniline (PANI), polypyrrole (PPY), polyindole (PIN), polyanthranilic acid (PANA), polycarbazole (PCZ), polyacrylonitrile (PAN), functionalized multi-walled carbon nanotubes (MWCNT-COOH), and camphorsulfonic acid (CSA). Blends and in-situ polymerization techniques were utilized to increase the desired thermoelectric/piezoelectric response. Nanofiber systems were produced utilizing the Forcespinning® technique. The morphology, structure, electrochemical, thermal stability, thermoelectric, and piezoelectric performance was analyzed. All of the nanofiber PVDF/CP …

Assessing The Feasibility Of A Biofilter In Medium-To-High Scale Industries, Javier A. Garcia

Theses and Dissertations

The removal of volatile organic compounds, VOCs, from contaminated sources of air stream has become a major air pollution risk. Excessive amounts discharged to the atmosphere are highly risky to human health and to the environmental system. Demand for sustainable VOC control technologies has become crucial for the reduction of emissions. Biological treatments of waste gas streams, such as biofiltration, have proven to be cost effective and environmentally friendly compared to conventional pollution control technologies. The goal of this research is to simulate data for a given biofilter model, and to evaluate if it is economically and environmentally feasible to …

Multi-Degree Of Freedom Position And Attitude Control Of Rings Dipoles Using Electromagnetic Forces And Torques, David Andres Alvarez

Theses and Dissertations

Satellite formation flight (SFF) is likely to transform and advance the scope of space missions in the near future. Some considerable benefits of SFF to a mission include robustness, adaptability, and potential cost savings. However, satellite formations face a fuel expenditure issue: the more spacecraft there are to control, the more fuel will be expended on alignment and maneuvering. A solution to this problem is Electromagnetic Formation Flight (EMFF), which is the application of conductive coils in producing electromagnetic fields that can interact with the fields of other coils in a formation to exchange forces and torques. With three orthogonal …

Modeling And Energy Simulation Of A Zero Energy Building: A Case Study For Florida, Mariana Migliori Favaretto

Theses and Dissertations

The study of energy consumption in buildings is an important area of research given the large share of building sector in the worldwide energy usage. The energy consumption of buildings has a high impact on carbon emissions, a greenhouse gas which has proved to play a major role in global warming. In the last decades, global warming has become an increasing concern and worldwide high energy demand have awaken a pressing quest towards improving building energy efficiency. Reducing buildings’ energy usage by implementing energy efficiency measures is one way towards a sustainable future for any country in the world. This …

Inverse Methods For Near-Real Time Estimation Of Surface Heat Flux In Thermal Protection Systems For Space Vehicles, Obinna Oluchukwu Ugochukwu Uyanna

Theses and Dissertations

With the increased goal of manned explorations to outer space, safety during the atmospheric entry/reentry process is paramount as the incident heat fluxes on the surface of vehicle can reach critical values. Thermal Protection Systems (TPS) are therefore essential components in space vehicles as they ensure the safety and protection of the payload and cargo. In order to ensure improved active control capabilities and prolonged used of the vehicle, TPS surface conditions need to be known and determined. Since direct measurement of the surface heat flux using sensors is not feasible, one alternative involves the use of temperature sensors located …

Flagellation Testing Of Composite Finger Skirts For Surface Effect Ship (Ses) Application, Natalie Marie Holliday

Theses and Dissertations

The objective of this research is to create flagellation data for SES finger skirts. The SES design allows it to have a high tonnage with low draft, little drag, low wavemaking resistance, remarkable carrying capacity, and incredible propulsive efficiency. A SES is a sidehull hovercraft, with air cavity sealing components at the bow and stern. The fingers at the bow collectively make up an elastic, flexible full sealing skirt, dissipating oncoming waves and allowing for the vessel to be self-stabilizing. The problem with SES vessels is that the bow finger skirts wear significantly over a short period of time (~ …

Feasibility Study Of Portable Solar Powered Blood Storing Refrigerator, Saroj Subedi

Honors Theses

This report is focused on the preliminary feasibility of portable solar-powered blood-storing refrigerators primarily based on calculations of energy required to maintain the temperature of the refrigerator, the electricity required throughout the day, calculating sufficiency of power supplied by the solar panel, and selection of battery for power storage. The method and the trend of a feasibility study involve the study of blood properties, separation of blood components after donation, and their storage conditions. Then, the portable size of the refrigeration has been proposed with three different compartments for storage of each blood component. The further methods involve the selection …

Apiary Wagon Frame, Katelyn Franklin, Ryoma Thomas

Honors Theses

The objective of this thesis to demonstrate how our senior capstone project team took a product from a concept to a mass production manufacturing operation, using the knowledge and experience gained through our four years in the Haley Barbour Center for Manufacturing Excellence (CME). Our product, the Apiary Wagon Frame, is an opportunity to reduce the barrier to entry into the hobbyist beekeeping community. In the design process for the Apiary Wagon Frame, we tested several prototypes and different fabrication methods, ending with a product capable of holding twenty hive frames. After building our final prototype, the group created a …

Introduction Of New Value Stream Through Vermicomposting Process, James Spalding, Joseph Harris

Honors Theses

The purpose of our project is to analyze whether a waste byproduct can be monetized into a viable profit stream for Wonderbird Spirits. Spent grain, a waste byproduct created by the distillation process, is currently the company’s biggest source of material waste. The CME project team designed and built a trommel to aid liquid-solid separation of the spent grain so that the solid portion can be repurposed as feedstock for a vermicomposting setup. We also suggest vermicomposting setup for the distillery based on the needs and capabilities of Wonderbird Spirits. We present financial analyses detailing the cost of creating the …

Creation Of A Wooden Model Toy Car As A Learning Module For Students Enrolled In Manufacturing 152, Patrick Brown

Honors Theses

This project involved the design and manufacture of a children’s wooden model toy car constructed on the CME factory floor. Apart from building a children’s toy, the purpose of this project was to introduce younger CME students to a high-quality product made efficiently in regards to manufacture time and total cost. The design for the car required the inclusion of principles from different manufacturing philosophies taught in the CME such as LEAN Manufacturing, which works to eliminate waste from a process, and Design for Manufacture and Assembly, which seeks to reduce cost and cycle time for a product. Through the …

Microstructural Evolution And Mechanical Properties Of L-Pbf Aerospace Alloys: Hydride- Dehydride Ti-6al-4v And Experimentally Heat-Treated Inconel 718, Jaime Varela

Open Access Theses & Dissertations

Experimental HIP and heat treatment cycles were applied to Laser Powder Bed Fusion fabricated Inconel 718 parts. Recent advances allow for rapid cooling in the HIPing chamber allowing one unit to perform HIP along with other heat treatment cycles such as solution annealing and ageing. Different cycles yield various effects on the porosity reduction as well as the growth of grain in the microstructure, consequently presented different mechanical properties. Specimens were therefore analyzed for density, microstructure, and tensile properties.

In addition, the mechanical and microstructural analysis of HDH Ti-6Al-4V was performed. The high cost of GA Ti64 material is a …

Development Of A Variable Extensometer Method For Measuring Ductility Scaling Parameters, Adam J. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ductility is the measure of how much a material can stretch before separation. It is usually measured in percent elongation, which is the amount a material stretches divided by its original length before stretching. This is an important property to understand for both the design for performance and safety. A material’s ductility can be influenced by several factors including heat treatment, machining, temperature, and radiation dose. Materials used in nuclear energy facilities are often exposed to all these factors, and it is important to be able to understand ductility at each possible combination.

Ductility is usually characterized through tension tests …

Multiscale And Multimaterial 3d Printing: Impact Of Feedstock Properties And Processing Parameters On Printed Parts, Kazi Md Masum Billah

Open Access Theses & Dissertations

Material extrusion additive manufacturing (AM) technology is one of the most commonly used technology to fabricate functional prototypes and end-use application parts with custom design. The evolution of the extrusion technology led this particular AM process to grow in many aspects such as new materials development, new design thinking, fabrication of parts in multiscale length, and manufacturing of monolithic parts with multiple functionalities. The research presented in this Dissertation results in the creation of knowledge in material extrusion AM technology with the length scale of production-grade to large-scale 3D printing machine those were used to enable the fabrication of multimaterial …

Fabrication And Testing Of Advanced Composites For Extreme Environments, Victoria Centeno

Open Access Theses & Dissertations

The following research focuses on the additive manufacturing and characterization of epoxy syntactic foams that utilize hollow carbon microspheres (CMS) and graphene-coated hollow carbon microspheres (GCMS) as fillers. The matrix that is utilized in this study is a thermoset epoxy resin, chosen for its high strength, low shrinkage, excellent adhesion to various substrates, effective electrical properties, chemical and solvent resistance, low cost, and low toxicity.1 CMS and GCMS were used as fillers for the properties they contribute to the overall epoxy syntactic foam, and can be seen in Fig.1.1. CMS consist of outer stiff carbon and inner gas, giving the …

Image Analysis Of Charged Bimodal Colloidal Systems In Microgravity., Adam J. Cecil

Electronic Theses and Dissertations

Colloids are suspensions of two or more phases and have been topics of research for advanced, tunable materials for decades. Stabilization of colloids is typically attributed to thermodynamic mechanisms; however, recent studies have identified transport or entropic mechanisms that can potentially stabilize a thermodynamically unstable colloidal system. In this study, suspensions of silsesquioxane microparticles and zirconia nanoparticles were dispersed in a nitric acid solution and allowed to aggregate for 8-12 days in microgravity aboard the International Space Station. The suspensions were subsequently imaged periodically at 2.5x magnification. Due to the inadequacy of existing image analysis programs, the python package “Colloidspy” …

Additive Manufacturing And Mechanical Properties Of The Dense And Crack Free Zr-Modified Aluminum Alloy 6061 Fabricated By The Laser-Powder Bed Fusion, Abhishek Mehta, Le Zhou, Thinh Huynh, Sharon Park, Holden Hyer, Shutao Song, Yunali Bai, D. Devin Imholte, Nicolas E. Woolstenhulme, Daniel M. Wachs, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

For additive manufacturing such as laser powder bed fusion (LPBF), commercial aluminum alloy (AA) 6061 is typically considered unsuitable due to formation of solidification cracking and/or excessive porosity. In this study, to improve buildability/printability of AA6061, 1 wt% of Zr was alloyed to produce Zr-modified AA6061 by LPBF. Powders of unmodified and Zr-modified AA6061 were produced by gas atomization, and utilized as a feed-stock for the LPBF to fabricate specimens for microstructural examination and mechanical testing. The as-built unmodified AA6061 exhibited poor printability due to formation of cracks and porosity in the microstructure regardless of LPBF parameters. However, the Zr-modified …

High Strength We43 Microlattice Structures Additively Manufactured By Laser Powder Bed Fusion, Holden Hyer, Le Zhou, Qingyang Liu, Dazhong Wu, Shutao Song, Yuanli Bai, Brandon Mcwilliams, Kyu Cho, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

WE43 is a high strength, high creep resistant Mg-alloy containing Y, Nd, and Zr, and has potential for many lightweight structural applications in the automotive, aerospace, and biomedical industries. Additive manufacturing technology such as laser powder bed fusion (LPBF) brings an opportunity to produce complex geometries such as lattice structures. In this study, fabrication, compressive behavior, and fracture modes of 24 different microlattice structures were investigated by varying unit cell type, strut diameter, and number of unit cells. These complex lattice structures were produced by LPBF using the parameter set: laser power = 200 W, scan speed = 1100 mm/sec, …

Automated Bottling Station - Packaging System, Lauren Nicole Zinzilieta

Honors College Theses

This report focuses on the packaging system used at the end of the FESTO bottling station that is located in EP 2355. The system will be made up of an x-y 300 mm x 300 mm gantry system, an Arduino, two micro-stepping stepper drivers, and two 152.4 mm (6 in) single acting cylinders with a 3D printed bracket attached to both. The gantry system will be located at the end of the conveyor belt and will be programmed to pick up three bottles at a time and then will move a specified number of steps in both the x and …

Aloe Vera Extract-Based Composite Nanofibers For Wound Dressing Applications, Raul Barbosa, Alexa Villarreal, Cristobal Rodriguez, Heriberto De Leon, Robert Gilkerson, Karen Lozano

Mechanical Engineering Faculty Publications

Natural, biocompatible, and biodegradable composite nanofibers made of Aloe vera extract, pullulan, chitosan, and citric acid were successfully produced via Forcespinning® technology. The addition of Aloe vera extract at different weight percent loadings was investigated. The morphology, thermal properties, physical properties, and water absorption of the nanofibers were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The developed nanofiber membranes exhibited good water absorption capabilities, synergistic antibacterial activity against Escherichia coli, and promoted cell attachment and growth. Its porous and high surface area structure make it a potential candidate for wound dressing …

Design And Optimization Of An Array Of Hollow Micropillar Structures For Enhanced Evaporative Cooling, Zhikai Yang

McKelvey School of Engineering Graduate Student Theses & Dissertations

With the increasing demand for higher-performance chips, the architecture of these semiconductor devices becomes more complex, leading to the need for higher-performance cooling technologies. For example, 3D stacked chips offer several advantages, including mixed functionality, reduced signal delay, and a smaller footprint. However, these devices yield higher heat densities due to the heat compounded from one stacked die to the next. While traditional single-phase cooling technologies can dissipate large heat fluxes, its performance is inversely proportional to its hydraulic diameter leading to larger required pumping powers. Two-phase cooling is a promising technique for dissipating high heat fluxes by utilizing the …

Analysis Of Fluid Flow In Redox Flow Batteries, Erfan Asadipour

McKelvey School of Engineering Graduate Student Theses & Dissertations

Redox flow batteries (RFB) hold great potential for large-scale stationary energy storage. However, their low energy density compared to other energy storage systems must improve for feasibility. Electrolyte flow distribution affects current density distribution and providing a uniform current density distribution is one way to improve RFB performance. Additionally, reducing the power consumption of the electrolytes’ pump as a source of energy loss in RFB systems increases their efficiency. Investigating both subjects requires analysis of the fluid dynamics in RFB cells.

In this thesis, a novel, computationally cost-effective hydraulic-electrical analogous model (HEAM) was developed to study fluid dynamics by implementing …

Plasma Aerodynamics: Experimental Quantification Of The Lift Force Generated On An Airfoil Using Plasma Actuation To Estimate Power Requirements In Small Uav Applications, Getachew Ashenafi

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research addressed the amount of electric power required to induce specific changes in lift force using a NACA 2127 airfoil with a chord length of ~28 mm, connected to a micro load cell, in a wind tunnel of 103 square centimeter cross-section. A DBD plasma actuator supplied by a ZVS driven high voltage pulsed DC circuit, operating at a frequency of 17.4 kHz, was utilized for voltages of up to 5000 V. Two configurations of electrode gapping were compared to determine the efficient use of power. The configuration with a gap of ~1 mm between the upstream and downstream …

Healthy Aging In Place: An Integrated Smart Home Using Alexa-Compatible Technology, Tyler Kryst

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research was to address current healthcare concerns among the aging population. Around the globe, the average life expectancy is projected to continue increasing resulting in a higher prevalence of age-related disease. With the ever-increasing capabilities of modern technology, it is necessary to apply this technology to increase the health and safety of older adults. This work had three objectives. The first objective was the establishment of an integrated smart home aimed at creating a healthy aging-in-place environment through the use of Alexa. The second objective was the development and integration of a completely custom health device …

A Hyperelastic Porous Media Framework For Ionic Polymer-Metal Composites And Characterization Of Transduction Phenomena Via Dimensional Analysis And Nonlinear Regression, Zakai J. Olsen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ionic polymer-metal composites (IPMC) are smart materials that exhibit large deformation in response to small applied voltages, and conversely generate detectable electrical signals in response to mechanical deformations. The study of IPMC materials is a rich field of research, and an interesting intersection of material science, electrochemistry, continuum mechanics, and thermodynamics. Due to their electromechanical and mechanoelectrical transduction capabilities, IPMCs find many applications in robotics, soft robotics, artificial muscles, and biomimetics. This study aims to investigate the dominating physical phenomena that underly the actuation and sensing behavior of IPMC materials. This analysis is made possible by developing a new, hyperelastic …

Patient-Specific Finite Element Analysis For Mandibular Fracture Fixation, Ethan Snyder

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis proposes an approach for Finite Element Analysis (FEA) of mandibular fracture fixation. Using a Computerized Tomography (CT) scan of mandible obtained from a specific person, the material characteristics, density and modulus of elasticity, were determined from a set of discrete points within the mandible that are 1mm spaced based on the Hounsfield Units of these points. The mandible geometry was sectioned to simulate a fracture. Muscle and mastication forces were added to replicate post-surgery loading. Using a standard linear miniplate, this material model was compared with two commonly used mandibular cortical shell bone models: isotropic and orthotropic. A …

The Effect Of Simulated Mangrove Forest Width On Shoreline Stabilization At Multiple Tidal Water Levels, James Edward Austin

Theses and Dissertations

Red mangrove (Rhizophora mangle) forests protect hundreds of miles of Florida’s shorelines from erosion and wave damage associated with severe storms and daily wave action. Shorelines are often protected from erosion with man-made structures such as seawalls, revetments, and breakwaters. However, these man-made structures disrupt natural ecosystems and cause scour and erosion in surrounding areas. The presence of mangroves not only prevents erosion but shelters marine life and filters water, promoting ecological health. Mangroves are now being implemented for wave energy reduction and shoreline stabilization, but there is little quantitative data about the precise sediment transport induced or prevented by …

Centrifugally-Spun Ceramic/Carbon Composite Fibers And Their Use As Anode Materials In Li-Ion Batteries, Gabriel Gonzalez

Theses and Dissertations

The work in this thesis focuses in the study of Centrifugally Spun Short Fiber Composites and their Implementation as Alternate Anode Material in Li-Ion Batteries. Due to their high theoretical capacity, abundance, and environmental friendliness, metal oxides have been widely studied as alternate anode materials for lithium ion batteries (LIBs). In this research work, the processing of SnO2 and SnO2/TiO2 ceramic short fibers as well as flexible and porous metal oxide carbon fibers (FPMOCFs) by centrifugal spinning followed by an optimized coating technique is reported. In addition, the electrochemical performance of the composites was also investigated and is provided.

Study Of Particle Size Effect On The Performance Of Tio2 Nanoparticles As Lubricant Additives On Vegetable Oil-Based Nanolubricants, Dario F. Rodriguez

Theses and Dissertations

Recently there has been an increase in concern regarding the use of petroleum-based lubricants. This has created an interest in readily available biodegradable lubricants such as vegetable oils. This work evaluates the rheological and tribological performance of grapeseed, and sunflower oils altered with 5, 18, and 40 nanometer titanium dioxide (TiO2) nanoparticles at differing concentrations. Block-on-ring tests were performed using the ASTM G-077-05 standard procedure. The effect of nanoparticle size and concentration and shear rate on the viscosity were evaluated and the experimental data was compared to conventional models. Roughness tests were performed on the wear scar of the blocks …

Secondary Resonances Of Electrostatically Actuated Mems And Nems Circular Plates, Julio S. Beatriz

Theses and Dissertations

Two methods are used in the investigation, which are the Method of Multiple Scales (MMS) and the Reduced order Model (ROM) with up to 6 modes of vibration. The MMS is done in three ways, one based on soft excitation and the other models based on the usage of the bookkeeping parameter, ε, in the electrostatic term. These are referred to as the 1 term no ε, and the 2 term no ε, which allow it to model hard excitation. The influence of the number of terms in the Taylor expansion is explored.

These methods are used to investigate the …