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Engineering Model To Calculate Mass Flow Rate Of A Two-Phase Saturated Fluid Through An Injector Orifice, Brian J. Solomon

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

An engineering model is developed to calculate mass flow rate of nitrous oxide, a self-pressurizing saturated oxidizer commonly used in hybrid rocket motors. While use of N_{2}0 cannot be accurately modeled using traditional ideal gas, compressible, or incompressible flow assumptions. To obtain accurate mass flow rate this one-dimensional analysis includes both incompressible fluid and homogeneous equilibrium mass flow rate models. Mass flow calculations from the two models are independently weighted and summed to obtain representative two-phase mass flow rate. Fluid properties are iterated in time by keeping track of fluid enthalpy and are propagated across the injector using either isentropic …

An Examination Of Variables Which Influence High School Students To Enroll In An Undergraduate Engineering Or Physical Science Major, Christopher Porter

All Dissertations

The purpose of this study was to examine the variables which influence a high school student to enroll in an engineering discipline versus a physical science discipline. Data was collected utilizing the High School Activities, Characteristics, and Influences Survey, which was administered to students who were freshmen in an engineering or physical science major at an institution in the Southeastern United States. A total of 413 students participated in the survey.
Collected data were analyzed using descriptive statistics, two-sample Wilcoxon tests, and binomial logistic regression techniques. A total of 29 variables were deemed significant between the general engineering and physical …

The Redesign Of Mechanical Engineering 574: An Exploration In Deductive And Inductive Methods, Alyssa Janae Walker

Theses and Dissertations

Changes in the engineering industry have motivated the redesign of engineering curriculum in recent years. This report documents the redesign of Mechanical Engineering 574, a graduate course in engineering offered at Brigham Young University. The redesign was divided into four phases and used a design narrative to report the design process. Research conducted by the instructor and designer informed the main content of the course. Although the course originally used mainly deductive methods of instruction, by the final phase of the project, the instruction evolved to be primarily inductive in strategy.

Automation Of Orthodontic Wire Tester For Performing Three Point Bending Tests, Adithya Venkatesan

Master's Theses

Abstract

Understanding the biomechanical factors in orthodontics is important in order to improve the overall effectiveness of actual clinical treatment. An accurate method to study the threedimensional (3D) force systems and the resulting movements of teeth during orthodontic treatment is needed along with the understanding of the material properties of any orthodontic wire. Until recently, most of the orthodontic biomechanics literature was limited to twodimensional experimental studies. Recent advances in threedimensional computer modeling have also been developed but have been limited to the manual control of tooth movement. Overall, there is very little published evidence in the literature on the …

Experimental Characterization Of Fuel Cell Gas Turbine Power System And Determination Of Optimal Trajectories Of Operation Using A Model Predictive Controller, Bernardo Restrepo

Graduate Theses, Dissertations, and Problem Reports

Hybrid Performance (HyPer) hardware simulation facility installed in the National Energy Technology Laboratory (NETL), U.S. Department of Energy is a hardware in the loop technology that couples a real recuperated gas turbine cycle with a Solid Oxide Fuel Cell (SOFC) Model. The system is composed of a gas turbine, two high-efficiency recuperators, three different bypasses, and several associated pressure vessels and pipes that represent the volumes and flow impedance of the fuel cell. The real-time fuel cell model is used to control a gas burner which replicates the thermal output of a SOFC. Control of thermal energy in and out …

Distributed Algorithms For Initialization And Topology Control In Wireless Ad Hoc Networks., Subhasis Bhattacharjee Dr.

Doctoral Theses

Wireless ad hoc networking is an upcoming communication technology that makes exchange of information possible without any pre-existing infrastructure. Over the last decade it has grabbed tremendous interest in the research community due to its easy deployability and high flexibility, with numerous applications to social, industrial and personal uses. In this thesis, we designed effcient light weight distributed algorithms based on minimal local information to resolve the problems related to the initialization and topology configuration of wireless ad hoc networks with special emphasis on optimal utilization of limited resources. Once the ad hoc nodes with in-built radio transceivers are deployed …

A Hemodynamic Investigation Of A Complete Arteriovenous Model Of The Arm, Arteriovenous Fistula, And Distal Revascularization And Interval Ligation, Nicole Varble

Theses

One of the largest problems facing vascular surgeons today is malfunctioning arteriovenous fistulas (AVF) in patients on hemodialysis. A radial- cephalic AVF is a vessel in the arm that directs blood flow from the high pressure arteries to the low pressure veins and is put in place so blood can be withdrawn from a patient at a point where high volume blood flow occurs. After a period of maturation, the fistula often expands to adapt for the increase flow and can therefore be accessed repeatedly for hemodialysis. However, in a small percentage of cases, access related steal can lead to …

Thermodynamic Based Model Eliciting Activities For Undergraduate Mechanical Engineering Education, Paul Nicholas Van Bloemen Waanders

Master's Theses

Undergraduate engineering education is designed to prepare students for their careers. The rise of technology in modern engineering allows for a shift in the way undergraduates are prepared for the modern workplace. Model Eliciting Activities (MEAs) allow students to think critically about their own work and allow instructors to analyze the students’ problem solving methods. To ensure that new MEAs are as effective as possible they are subject to six basic principles: model construction, reality, generalizability, self-assessment, model documentation, and effective prototype.

This document focuses on evaluating new MEAs for their adherence to the six principles from an instructor's and …

Learning To Fly: The Untold Story Of How The Wright Brothers Learned To Be The World's First Aeronautical Engineers, Daniel Lawrence Slusser

Master's Theses

This paper examines the education, events, and experiences of the Wright brothers in order to determine how they developed the necessary skills to engineer the first viable aircraft. Without high school diplomas, and with no advanced formal education, the Wright brothers were able to develop aircraft that far exceeded the capabilities of aircraft designed and built by professional engineers that had worked on the problem of flight for much longer and with substantially larger research budgets. I argue that the Wright brothers’ success resulted from their experiences in the printing and bicycle industries as well as their formal and informal …

Interaction Between Primary Resources And Root Causes In Lean Production Systems, Ernest Anene Iwuchukwu

Masters Theses

A model to analyze lean systems reliability is developed based on the premises that lean production systems require four primary resources; materials, equipment, personnel, and schedule (Sawhney, R., Subburaman, K., Sonntag, C., Capizzi, C. and Rao, P.V., 2009). The four primary lean resources were independently analyzed, without due consideration to underlying relationships within each other. In this research, relationships and interaction between root-causes and lean primary resources were conceptualized and developed. The development applied a five-phase approach: 1. review of related literature, 2. decompositions of lean primary resources, 3. selection of consensus root causes items and questionnaire construct, 4. survey …

Studies On Public Key And Identity-Based Cryptographic Primitives., Mahabir Prasad Jhanwar Dr.

Doctoral Theses

No abstract provided.

An Approach To Improve The Failure Rate Model Of A Solid State Laser By Utalizing The Physics Of Failure Methodology, Omar L. Thompson

Electronic Theses and Dissertations

The ability to predict the failure rate of any military laser is very critical. In-field laser usage does not support the troubleshooting and repairing of a complex electro optical system. The only published laser failure rate model was last updated by the Department of Defense in 1975. Consequently, the failure rate predicted is inaccurate due to model deficiencies. This dissertation has developed a laser failure rate model for diode pumped lasers with improved failure rate prediction accuracy. The model has surpassed the capabilities of the Department of Defense model by the inclusion of key performance attributes that are currently not …

Control Of A Large Scale Wind Turbine Utilizing A Fluid Drive, Matthew Foley

Master's Theses and Capstones

As wind turbines grow in size there are added strains within the mechanical structure that need to be mitigated to improve machine life. The current area of greatest concern is the premature failure of the gearbox box due to torque variations along the drive train. This thesis incorporates a fluid coupler into the turbine's drive train. Three different controllers are developed for this model with the goal of minimizing the torque variations seen by the gearbox and providing better generator speed regulation.

The result of this study shows that the addition of the fluid coupler is a major improvement to …

Synthesis Of Cadmium Selenide-Gold Hybrid Nanorods, Xiaoxiong Jia

Master's Theses and Capstones

In this work, we reported the synthesis of cadmium selenide-gold (CdSe-Au) hybrid nanorods. The growth substrates, CdSe nanorods, were synthesized using a simple mono-injection method. The growth models for CdSe with different morphologies were proposed, and validated by the experimental results. It can be briefly described as concentrated CdSe monomers were prone to forming isotropic CdSe nanoparticles; while diluted CdSe monomers were prone to forming anisotropic CdSe nanorods. The growth of Au nanoparticles on the surface of CdSe nanorods was achieved via galvanic replacement reactions between Au ions (AuCl3) and CdSe nanorods at room temperature. By adjusting the reaction times, …

Analytical And Numerical Modeling Of Performance Characteristics Of Cross-Flow Hydrokinetic Turbines, Alex J. Johnston

Master's Theses and Capstones

A model for cross-flow axis hydrokinetic turbines based on blade element theory (BET) was developed. The model combines an extensive experimental and numerical high Reynolds number data set for symmetric airfoils with governing equations to predict performance characteristics of the turbines. In this model the freestream velocity and the turbine's rate of rotation are not coupled hydrodynamically; experimental calibration of the model for a specific turbine design is necessary. The calibrated model uses velocity data from a tidal energy site to predict power and energy yield over a full tidal cycle. The experimentally calibrated model is compared to a single …

Accelerometer Calibration For Nasa's Magnetospheric Multiscale Mission Spacecraft, Benjamin M. Jenkins

Master's Theses and Capstones

This thesis presents several methods for the on-board and/or ground-based calibration of accelerometers for the spacecraft (s/c) of the NASA Magnetospheric Multi-Scale (MMS) Mission during mission operation. A lumped bias is estimated to correct for the total effect of the MMS accelerometer sensor bias, orthogonal misalignment and the shift in the s/c's center of mass.

Various estimation techniques are evaluated and compared, including both dynamically driven real-time filters/observers and post processing batch algorithms. Both methods are shown to accurately determine lumped bias, so long as the s/c inertia tensor is well known. If, however, there is any uncertainty in the …

Regional Harmonization Procedure For Prioritization Of Recycled Material Specifications, Courtney Goldstein

Master's Theses and Capstones

Widely varying recycled material requirements across state lines has been perceived as a significant barrier to greater use of recycled materials in highway construction by state contractors and industry. The goal of this thesis is to create a procedure to compile, compare, contrast and finally synthesize documents that support a priority list of recycled materials and applications for which material specifications can be harmonized among regional states in the US.

This work compiled background research on selected materials and related regulations into standardized templates. The information analyzed was communicated with EPA, FHWA, and state representatives to approve a breakdown priority …

On The Ability Of Indentation To Capture The Anisotropic Elastic Properties Of The Pyrolytic Carbon, Nikolay Timoshchuk

Master's Theses and Capstones

We used micro- and nanoindentation, macroscopic strain gage methods and FE studies to correlate the indentation modulus and the macroscopic in- and out-of-plane Young's moduli of transversely isotropic pyrolytic carbon. The out-of-plane indentation modulus of bulk PyroC was comparable with predicted values and more than a factor of two higher than the out-of-plane Young's modulus. The in-plane indentation modulus was significantly lower than predicted values which we attribute to nanobuckling of graphite-like planes. Polarized light microscopy studies on carbon-carbon composite samples infiltrated at 10, 20, 30 kPa demonstrated that the increase in pressure leads to lower texture of the PyroC …

Comparing The Sustainability Of Two Surface Water Treatment Alternatives Using Life Cycle Assessment (Lca), Michaela L. Bogosh

Master's Theses and Capstones

A sustainability assessment which combines the academic strengths of university research modeling with the practical inputs and needs of an operating utility is presented to compare two water treatment alternatives. PWN Water Supply Company is evaluating an upgrade from their current conventional coagulation and sand filtration (CSF) treatment process at WTP Andijk to Suspended Ion Exchange with Ceramic Microfiltration (SIX/CeraMac). An initial LCA was performed to determine which pretreatment is more sustainable in terms of energy consumption and carbon footprint.

The initial LCA indicated that treatment with SIX/CeraMac exhibits a lower impact as measured by kg of carbon dioxide equivalents …

Field Calibration Methodology For A Multibeam Echo Sounder Using A Split Beam Sonar System And A Standard Target, Jose Carlos Lanzoni

Master's Theses and Capstones

A method to determine the combined transmit/receive beam pattern for a ship-mounted multibeam system was developed and tested at distances of up to 8 m using a RESON 7125 MBES inside the fresh water calibration tank of the University of New Hampshire. The calibration method employed a tungsten carbide sphere of 38.1 mm diameter as the target and a SIMRAD EK60 split-beam sonar system to provide athwartship and alongship angular information of the target sphere position.

The multibeam sonar system was configured for 256 beams in equi-angle mode with an operating frequency of 200 kHz; the split-beam system was set …

Long Term Performance Of High Rap Sections---Case Studies, Evan D. Anderson

Master's Theses and Capstones

This thesis presents the summary of several case studies on the long term performance of high recycled asphalt pavement (RAP) sections. Roadway sections which contained more than 20% RAP and that had been in place for at least 10 years were identified from across the United States and Canada with the help of the local agencies. The long term performances of these various recycled sections were compared directly to mixes made with similar virgin materials via measurements of distress criteria. These distress criteria included rutting, cracking, ride quality, and any overall performance rating that the local agencies used in evaluating …

Performance Evaluations Of Hma Containing Reclaimed Asphalt Pavement And Reclaimed Asphalt Shingles, Jennifer Foxlow

Master's Theses and Capstones

The use of recycled materials in the form of Reclaimed Asphalt Pavement (RAP) and Reclaimed Asphalt Shingles (RAS) in Hot Mix Asphalt (HMA) has become regular practice; however, when compared to the supply of these materials their use is still conservative. Comparative studies on the performance effects are needed to propose guidelines for the handling, processing, and incorporation of RAS and high RAP into mix design procedures. Presented here are results of examining lab produced HMA containing RAS and RAP. The RAS study indicates no significant difference in the stiffness in RAS vs. RAP mixes across most temperatures, and that …

Patterns Of Motion: Discovery And Generalized Representation, Imran Saleemi

Electronic Theses and Dissertations

In this dissertation, we address the problem of discovery and representation of motion patterns in a variety of scenarios, commonly encountered in vision applications. The overarching goal is to devise a generic representation, that captures any kind of object motion observable in video sequences. Such motion is a significant source of information typically employed for diverse applications such as tracking, anomaly detection, and action and event recognition. We present statistical frameworks for representation of motion characteristics of objects, learned from tracks or optical flow, for static as well as moving cameras, and propose algorithms for their application to a variety …

Development Of A Semi-Automated Tobacco Stripping Machine Utilizing String Trimmers, Robert George Sperry

University of Kentucky Master's Theses

Conventional stripping of burley tobacco is labor intensive and typically requires 50 to 75 worker hours per acre (wkr•hr/ac). The goal of the project was to reduce labor by optimizing leaf removal by string trimmer heads using combinations of strings lengths and motor speeds. In tests conducted on a single grade, all leaves outside the grade were removed by hand. Plants were run through the machine for sting lengths of 5, 7 and 9 inches and associated motor speeds which were monitored and recorded. Stripping efficiencies were calculated for each plant and collectively for each set of four plants. The …

In-Situ Early Detection Of Metal Corrosion Via "Turn-On" Fluorescence In "Smart" Epoxy Coatings, Anita Augustyniak

Doctoral Dissertations

Organic coatings (e.g., epoxy coatings) have been widely used to protect metal and metal alloys against corrosion. However protective coating fails with time, leading to corrosion of the metal substrate. When localized corrosion occurs, without being detected, it can result in disastrous failure of the metal structure. The purpose of this thesis is to develop a "smart" epoxy coating system that detects early stages of metal corrosion via indicators molecules embedded in the coating that fluoresce when triggered by ions liberated from corrosion. This fluorescence can be easily and non-destructively detected and thus further material damage can be prevented by …

Analytical And Numerical Prediction Of Localized Necking In Sheet Metal Forming Processes, Raed Zuhair Hasan

Doctoral Dissertations

The goal of this research is to investigate, develop and validate analytical and numerical tools that can accurately predict failure in sheet metal forming operations. The strain-based forming limit curve (FLC) is one of the tools to predict the maximum permissible strains of thin metallic sheets which are loaded in the plane of the sheet to different states of stress. It may be used to assess forming operations in the press shops as well as unintentional deformations, such as vehicle, aircraft, or train crashes. The accurate prediction of failure in sheet metal stamping can shorten product lead times, decrease tooling …

A Computational Fluid Dynamics Study Of Two-Phase Flows In The Presence Of Surfactants, Yuanyuan Cui

Doctoral Dissertations

Drop formation in co-flowing fluids and drops rising in a tube are important in applications such as microencapsulation and enhanced oil recovery. A hybrid volume-of-fluid method with a front-tracking scheme is developed to study two-phase flows in the presence of surfactants at finite Reynolds numbers. Both fluids can be Newtonian or shear-thinning, and surfactants are soluble in the adsorption-desorption limit. A drop in the co-flowing geometry typically breaks up at the primary neck. The drop breaks faster with smaller volumes as the outer flow rate increases or the drop viscosity decreases. When surfactants are present, they accumulate in the neck …

Hydrogenation Of Nanostructured Carbon, Synthesis Of Organic Semiconductors And Progress Towards Synthesis Of Fullerenes And Nanoribbons From Polyaromatic Hydrocarbons, Jeremy T. Kintigh

Doctoral Dissertations

The hydrogenation of carbon allotropes including fullerenes, nanotubes and graphene was investigated using polyamines as hydrogenation reagents. In each case, a rapid, scalable and reversible hydrogenation was observed. The mechanism of hydrogenation was explored using several different polyamines. It was shown that a two-carbon spacer between amine groups is critical for efficient hydrogenation, as well as the presence of at least two adjacent amines that are not tertiary. The extent of hydrogenation on the fullerenes is a function of reaction temperature. C3nuC 60H18 forms preferentially at approximately 200 °C whereas C60H36 species are preferentially formed at approximately 340 °C and …

A Comparative Study Of Reactive Caps For Polycyclic Aromatic Hydrocardons In Sediment, John D. Anderson

Master's Theses and Capstones

Some of the most common byproducts from industrial production and hydrocarbon combustion are polycyclic aromatic hydrocarbons (PAHs). These compounds readily adsorb to lake and river sediment, and represent a significant problem to humans and the environment. Capping technologies work as physical barriers between the contamination in the sediment and the greater ecosystem. In this study, capping performance is analyzed based on the removal efficiency of two different organoclay-based treatments and a sand treatment, and the loading rate of PAHs onto the treatment materials. PAH loading rate and removal efficiency indicate the material's ability to sequester PAHs from the aqueous phase …

An Experimental And Analytical Study Of The Mechanism Of Material Modification When A Bias Is Applied Between Afm Tip And Gold And Highly Oriented Pyrolytic Graphite, Anjali Parkhi

Master's Theses and Capstones

The fabrication of nanostructures is of great importance for the continued development of nanodevices and molecular electronics. While field assisted tip based techniques are proposed to be versatile nanofabrication techniques that can be used for atomic-scale surface modification of wide variety of materials, the mechanism of material transport is not well understood. This research was performed to better understand the mechanisms of surface modification when the voltage bias is applied in ambient conditions; in particular, the conditions that Liu et al.1,2 proposed will cause material transport.

We studied the evolution of the current voltage behavior of a doped silicon AFM …