Mechanical Engineering Commons^™

Origami: Numerical Solutions Of Apparent Absorptivity In Origami Folds, Michael Farnsworth, Brian Iverson

Journal of Undergraduate Research

There are three major types of heat transfer: conduction, convection, and radiation. In many cases, radiation is ignored due to the fact that the amount of heat transferred by this method tend to be small compared to conduction and convection. However, in space and in some settings on earth, radiation is dominant and important. Absorptivity is a measure of an object’s ability to absorb radiation, and apparent absorptivity is a measure of how the shape of an object affects the amount of radiation that it absorbs. For example, if you were to shine a flashlight on a mirror, the light …

Fabrication And Study Of The Structure And Magnetism Of Rare-Earth Free Nanoclusters, Bhaskar Das

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

No abstract provided.

Design And Development Of A High Altitude Wind Tunnel (Hat), David Ritchie

Research Horizons Day Posters

No abstract provided.

Size Distribution Of Carbon Nanoparticles From A Methane/Argon Hv Pulsed Dc Ampj, Steven Doyle

Research Horizons Day Posters

No abstract provided.

Turbulent Boundary Layer Features Via Lagrangian Coherent Structures, Proper Orthogonal Decomposition And Dynamic Mode Decomposition, Naseem Ali, Murat Tutkun, Raul Bayoan Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

High-speed stereo PIV-measurements have been performed in a turbulent boundary layer at Reθ of 9800 in order to elucidate the coherent structures. Snapshot proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) are used to visualize the flow structure depending on the turbulent kinetic energy and frequency content. The first six POD and DMD modes show the largest and the lowest amount of energy and frequency, respectively. Lagrangian coherent structure (LCS) based on the algorithm developed using the variational theory is also applied to track the flow via attracting and repelling trajectories. The shapes and the length of the trajectories …

Characterization Of A Small Electro-Mechanical Contact Using Non-Conventional Measurement Techniques, Kelsey M. Johnson

Mechanical Engineering ETDs

Currently there are limitations in computing chatter behavior of small electrical contacts embedded in components using finite element models. Reduced order models (ROM) have been developed of such electrical contact sub-assemblies to assess the chatter behavior of the contacts during vibration and shock environments. The current ROM method requires experimental validation. This ROM also neglects the damping effects of the viscous fluid that typically surrounds such sub-assemblies. Dynamic ring-down testing of the electrical contacts in air was performed and will provide a validation data set for the current ROM. Additionally, dynamic ring-down testing of the electrical contact was performed in …

Satellite Sequencing Optimization Using A Genetic Algorithm, Andrew Verstraete

Research and Creative Activities Poster Day

The problem of mission design for a robotic servicing satellite in geosynchronous Earth orbit (GEO) was investigated. A representative set of potential client satellites was selected, and operational needs were randomly assigned based on the average number of GEO retirements, anomalies, and repositioning maneuvers that currently occur each year. An objective function was developed to represent the value of servicing mission sequences, including client fees, time penalties, and operational risk. A genetic algorithm was then used to find sequences of operations on the potential client set that maximized the objective function’s value. Scenarios were analyzed with the database of satellites …

Turbulence Analysis For The Improvement Of Internal Combustion Engine Efficiency, James R. Macdonald, Claudia Fajardo-Hansford

Research and Creative Activities Poster Day

Developing a complete understanding of the structure and behavior of the near-wall region (NWR) in reciprocating, internal combustion (IC) engines and of its interaction with the core flow is needed to support the implementation of advanced combustion and operating strategies to improve engine efficiency. The NWR in IC engines is fundamentally different from the canonical steady-state turbulent boundary layers (BL), which have been extensively researched. Motivated by this need, this poster presents results from the analysis of two-component velocity data measured with particle image velocimetry near the head of a single-cylinder, optical engine. The interaction between the NWR and the …

An Interactive Web-Based Tool For Fatigue Analysis And Life Prediction, Daniel Kujawski

Faculty Research and Creative Activities Award (FRACAA)

• Interactive web-based tool creates a modern approach to fatigue analysis and life prediction for use in engineering classrooms.
• Bridge the gap between theory and reality.
• The unique attributes of this software allows engineering students to learn and gain more insight to fatigue analysis in a given semester.

The Mathematical Theory Of Deformation Arrest In Large-Strain Dynamic Plasticity, Brendan A. Kullback

Mechanical Engineering ETDs

Ductile structural components subjected to explosive loadings exhibit a large range of behaviors. The response of beams, walls, and blast doors is estimated using two methods. The engineering level approaches are highly simplified and neglect much of the relevant physics while the use of finite element or shock-code simulation is expensive and not suited to rapid problem solving and parameter studies. In this dissertation, a medium fidelity reduced order modeling approach has been derived to capture the most relevant physics governing rupture of ductile bodies dynamically deforming in tension.

Solution of the inertially stretching jet is used to reveal the …

Effect Of Thickness On Fatigue Life On Creased Thin Pla, Peter Schleede, Larry Howell

Journal of Undergraduate Research

Origami-based engineering creates products that solve problems inherent in other designs. For example, they can compress into smaller volumes, achieve new and unique motions, and lessen or mitigate numbers of welds, fasteners, or other joining methods. However, a weakness of these designs is the necessity of folding them and seams that result from that folding. If viable, 3D printing these designs would eliminate the need for complicated folding machinery or adhesives to close the seams. Since origami is, by its nature, dynamic, this research aims to help designers predict fatigue lives (number of cycles until failure) of thin, printed PLA …

Safety Of Tubular Nylon Webbing: The Effect Of Wet And Cold Environments, Caleb Duncan, Landon Wright, John Salmon

Journal of Undergraduate Research

Tubular nylon webbing is an effective and relatively inexpensive anchoring solution for search and rescue groups, fire departments, canyoners, and rock climbers. As an anchoring solution nylon webbing is vital to the safety of anyone who uses it. Serious injury or death will often occur if an anchor fails.

All commercially available webbing is labeled with a breaking strength so that the end user is aware of its limits. This breaking strength value is obtained by the manufacture after running many tensile pull tests of dry webbing. While the dry breaking strength is reported by the manufacture no information, other …

Droplets Rolling On Superhydrophobic Inclines Simulating Real World Application Environments, Braquel Burnett, Julie Crockett

Journal of Undergraduate Research

Superhydrophobic surfaces offer unique characteristics such as extreme water repellency, drag reduction and enhanced condensation rates. These effects are possible due to a combination of micro/nano-texturing and a hydrophobic chemical coating. With the advent of micro/nano-fabrication, research and development on superhydrophobic surfaces has sky-rocketed due to the potential advantages across multiple industries including lab-on-a-chip technology, micro-electronic cooling and anti-icing applications.

The Influence Of Crystallographic Constraints On Percolation, Jarrod Lund, Oliver Johnson

Journal of Undergraduate Research

Within polycrystalline materials (e.g. metals and ceramics), grain boundary networks (GBN) influence the effective properties such as diffusion, conductivity, and crack and creep propagation¹. In precision applications such as jet engine turbine blades and solid oxide fuel cells, understanding and characterizing GBN are essential for better design. Modeling GBN allow for better exploration of the complex space of possible networks (figure 1d)². By modeling grains in a honeycomb lattice (figure 1a), grain boundaries can be identified by their misorientation angle (figure 1b). This can be a key indicator of the grain boundary’s properties. By combining information …

High-Throughput Tensile Testing Reveals Stochastic Properties In Additively Manufactured Steel, Bradley C. Salzbrenner

Mechanical Engineering ETDs

An adage within the Additive Manufacturing (AM) community is that “complexity is free”. Complicated geometric features that normally drive manufacturing cost and limit design options are not typically problematic in AM. While geometric complexity is usually viewed from the perspective of part design, this advantage of AM also opens up new options in rapid, efficient material property evaluation and qualification. This Thesis demonstrates how 100’s of miniature tensile bars can be produced and tested for comparable cost and in comparable time to a few conventional tensile bars. With this technique, it is possible to evaluate the stochastic nature of mechanical …

Residential Code Review For The 2017 Florida Building Energy Code, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

The project reviews provisions of the proposed 2017 residential Florida building energy code in order to make a determination if it meets or exceeds the 2015 IECC code.

Method And Shear-Driven Micro-Fluidic Pump, Nihad E. Daidzic

Aviation Department Publications

United States Patent Application, Publication Number US 2017/0096990 A1, Publication Date April 6, 2017.

An example includes an apparatus to pump a fluid. The apparatus includes a housing extending along a length defining an elongate interior, an actuator in the housing, conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 10 to 200 micrometers across and an actuator configured to oscillate the actuator in the actuator housing along the length of the elongate interior with a rate differential between movement in a first …

Simulation And Analysis Of A Drilling Fluid Using A Herschel-Bulkley Model, Daniel Powell

Mechanical Engineering ETDs

In the study, a drilling fluid with known properties is analyzed and simulated in the laminar regime through a pipe with dimensions of 1.5m in length and 0.02m in diameter. The purpose of the conducted analysis is to demonstrate the advantages of the Herschel-Bulkley model currently used in the oil and gas industry for analyzing non-Newtonian drilling fluids.

For comparison, the analysis is also performed using more simple models for non-Newtonian fluids such as the Bingham Plastic model and the Power Law model and for a Newtonian fluid (water). In addition to analytical models, computations are conducted using …

Experimental Evaluation Of Cooling Effectiveness And Water Conservation In A Poultry House Using Flow Blurring® Atomizers, Rafael M. Rodriguez

USF Tampa Graduate Theses and Dissertations

Increases in population as well as economic improvements in developing countries are generating a larger demand for animal protein products. Current animal growth processes inherently, require the use of water in many forms throughout the growth cycle. Water is the most important natural resource on earth to sustain life, and in many developing countries is a scarce resource that must be used wisely. Studies have revealed that poultry growth can take place with less water consumption, when compared with other sources of animal protein (e.g., cattle, pork). In this research, an evaporative Flow Blurring^® cooling system was considered as …

Thermal Characterization Of Natural And Synthetic Spider Silks By Both The 3Ω And Transient Electrothermal Methods, Troy Munro, Changhu Xing, Heng Ban, Cameron G. Copeland, Randolph V. Lewis, Colby Jensen

Faculty Publications

Thermal conductivity, thermal diffusivity and volumetric heat capacity of three spider silks are measured in this paper as a benchmark for further studies. These silks include the major and minor ampullate silks of the Nephila clavipes spider, and a synthetic spider silk fiber made from recombinant dragline silk proteins purified from transgenic goats’ milk. Two complementary measurement techniques are employed in the thermal characterization of these microscale single fibers for self-verification. One is the transient electrothermal technique (TET) and the other is the 3ω method. Experimental measurements indicate that thermal properties of the dragline silk are very close to those …

Investigation Of Synthetic Spider Silk Crystallinity And Alignment Via Electrothermal, Pyroelectric, Literature Xrd, And Tensile Techniques, Troy Munro, Tristan Putzeys, Michael Wubbenhorst, Christ Glorieux, Cameron G. Copeland, Randolph V. Lewis, Changhu Xing, Heng Ban

Faculty Publications

The processes used to create synthetic spider silk greatly affect the properties of the produced fibers. This paper investigates the effect of process variations during artificial spinning on the thermal and mechanical properties of the produced silk. Property values are also compared to the ones of the natural dragline silk of the N. clavipes spider, and to unprocessed (as-spun) synthetic silk. Structural characterization by scanning pyroelectric microscopy is employed to provide insight into the axial orientation of the crystalline regions of the fiber and is supported by XRD data. The results show that stretching and passage through liquid baths induce …

Instructional Learning Aids For Gear Train Analysis In Machine Dynamics, William M. Bartholomew

Thinking Matters Symposium Archive

In this project, a few instructional aids to teach gear train analysis to students are designed and manufactured. The system will progressively be more complex in order to help students understand the concepts first, and then the applications which are based on those concepts. The project involves theoretical, simulation and manufacturing (3D printing or CNC) components.

Engine Analysis, Thomas Gaier

The University Honors Program

Engines were invented two hundred years ago but early dynamometers did not benefit from the technological advances until the last hundred years. A John Deere Model E hit-and-miss engine has a nominal power of3hp. The purpose of this project was to analyze this engine, including verifying power.

Outcomes of the analysis of this engine include brake horsepower and thermal efficiency. The first step was to put the engine under a load. This was done with a water pump system. Pressure, water flow, and rotation were measured from tests using the system.This type of system is analogous to a water brake …

Distillation-Resolved Evolution Of Key Combustion Properties, Francis Haas, Jay A. Lefkowitz

Henry M. Rowan College of Engineering Departmental Research

Many studies demonstrate successful emulation of pre-vaporized real fuel combustion through use of fuel surrogates. These surrogates may be described by a multiplicity of non-unique multicomponent formulations, each with pre-vaporized combustion behaviors that are essentially equivalent to the target real fuel and each other. However, many combustion applications employ fuel sprays, leaving some question as to the validity of pre-vaporized assumptions for these conditions. In the present work, a batch distillation model for ideal liquids is developed to predict the evolution of surrogate fuel combustion properties such as autoignition propensity (represented by an effective RON or DCN), hydrogen-carbon-oxygen atomic ratios, …

Room Acoustics: Measurement And Correction With A Portable Digital Signal Processor, Azad Jalali

Thinking Matters Symposium Archive

The frequency response of a listening space is often of great interest to anyone pursuing an accurate and undistorted listening experience. Here we successfully implement sine- sweep deconvolution on a hardware platform to demonstrate an easy, digitized way to measure and guide improvements to the audio dynamics of a room.

Tracking Characteristics Of Tracer Particles For Piv Measurements In Supersonic Flows, Fang Chen, Hong Liu, Zifeng Yang, Hui Hu

Mechanical and Materials Engineering Faculty Publications

The tracking characteristics of tracer particles for particle image velocimetry (PIV) measurements in supersonic flows were investigated. The experimental tests were conducted at Mach number 4 in Multi-Mach Wind Tunnel (MMWT) of Shanghai Jiao Tong University. The motion of tracer particles carried by the supersonic flow across shockwaves was theoretically modelled, and then their aerodynamic characteristics with compressibility and rarefaction effects were evaluated. According to the proposed selection criterion of tracer particles, the PIV measured results clearly identified that the shockwave amplitude is in good agreement with theory and Schlieren visualizations. For the tracer particles in nanoscales, their effective aerodynamic …

Design Optimization And Motion Planning For Pneumatically-Actuated Manipulators, Daniel Mark Bodily

Theses and Dissertations

Soft robotic systems are becoming increasingly popular as they are generally safer, lighter, and easier to manufacture than their more rigid, traditional counterparts. These advantages allow an increased sense of freedom in both the design and operation of these platforms. In this work, we seek methods of leveraging this freedom to both design and plan motions for two different serial-chain, pneumatically actuated manipulators developed by Pneubotics, a small startup company based in San Francisco. In doing so, we focus primarily on two related endeavors: (1) the optimal kinematic design of these and other similar robots (i.e., choosing link lengths, base …

Automated Impact Device, Jason Montavon

The University Honors Program

This report outlines the progress and development ofan automated impact device (AID). This device was designed to be inexpensive, user-friendly, and modular. Developed with the parameters of vibration analysis. the AID can perform a variety of experimental procedures. Using simple C code and components that are both affordable and easy to obtain, the AID was designed to perform the same task as its more expensive counterparts. With this thought-process, the device was engineered to easily and quickly interchange components depending on the required task. Outlined in the report is the code used to operate the AID and the basic components …

Fabrication And Characterization Of Alₓcofenicu₁₋ₓ High Entropy Alloys By Laser Metal Deposition, X. Chen, L. Yan, S. Karnati, Y. Zhang, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Effect Of Design Parameters On Thermal Performance Of A Vane Type Disc Brake Rotor, Yogesh Satish Dalal

Masters Theses

The ever-increasing need of effective transportation puts automobile manufacturers in a situation of continuous improvement and innovate the safety systems. The brake system of an automobile has always been considered as one of the most critical active safety systems. Thermal characteristics of the brake are an important aspect to consider for brake disc durability and performance. The convective cooling of a brake disc is an important factor since design changes in the brake rotor can significantly improve cooling characteristics. The focus of this research is to study and optimize the disc brake rotor for a given heat dissipation rate and …