Mechanical Engineering Commons^™

Surface Preparation Of Naval Ship Construction Steel (Abs-A And Ah-36) Via Bristle Blasting Process, Jorge Andres Martinez

Master's Theses (2009 -)

Bristle blasting is a new and unique corrosion-removal process that is rapidly gaining widespread acceptance among engineers and practitioners in the corrosion/ surface preparation community. Engineers from the ship construction and repair industries face a constant corrosive threat to ships' steel infrastructure and welded joints. To this end, great care is exercised in protecting the vessels' structural integrity and longevity, while maintenance engineers in the ship-building industry seek new methods to improve surface preparation that will not compromise the surface cleanliness and anchor profile required for proper adhesion of paints and coatings.

In this study, the cleanliness and texture of …

Direct Numeric Simulation Of Shock Wave Structures Without The Use Of Artificial Viscosity, Kenneth Bernard Jordan

Dissertations (1934 -)

The purpose of this work is to directly simulate shock wave structures without the use of artificial viscosity. The commonly used artificial viscosity model is replaced with an irreversibility model. Irreversibilities are not typically taken into account when modeling the shock processes because shocks are resolved in a large domain where the thickness of the shock is thin compared to the numeric grid resolution. The result is the shock is poorly resolved. In addition processes other than shock processes are adiabatic and reversible. The result is artificial viscosity, a form of irreversibility, is added to the numeric cells near the …

Virtual Prototyping Of A Mechatronics Device, Ryne P. Mchugh

Purdue Polytechnic Directed Projects

Mechanical, electrical, and embedded software engineering are being combined in modern products. This combination has come to be known as mechatronics. The high level of multidisciplinary interaction makes it difficult for collaboration and use of computers in Mechatronics’ design.

Dassault Systems’ SolidWorks and National Instruments’ LabVIEW are industrial grade softwares that can be used in the development and deployment phase of engineering design. SolidWorks is used for physical modeling and analysis of geometric parts, while LabVIEW is used as a programming language for control logic and data acquisition. National Instruments has developed a module, known as SoftMotion, which allows communication …

Refrigerant Mass Migration Modeling And Simulation For Air Conditioning Systems, Bin Li, Steffen Peuker, Predrag S. Hrnjak, Andrew G. Alleyne

Mechanical Engineering

Refrigerant mass migration and redistribution are regarded as key factors affecting the cycling performance of air conditioning and refrigeration systems. A dynamic model of an R134a automotive air conditioning system is presented as an example in this paper to capture the refrigerant migration during compressor shut-down and start-up operations. Model validation against experimental data demonstrates the capabilities of the modeling approach in predicting the refrigerant mass migration among the components during shut-down, and the resulting refrigerant redistribution behaviors during start-up. These results represent the first refrigerant mass migration prediction in a validated dynamic system model. In addition, the potential of …

Vibroacoustic Study Of Circular Cylindrical Tubes In Roller Coaster Rails, Joshua I. Davis, Charles Birdsong, Harold M. Cota

Mechanical Engineering

Excessive noise generated by roller coasters during operation is a significant issue for amusement parks located near residential and business districts. Previous work showed that filling the rails with sand and pea gravel can provide noise reduction levels of up to 10 and 15 decibels. However, using damping materials may require additional support structures to accommodate the weight increase and, consequently, raise installation costs. This paper presents field results that characterize sound and vibration of roller coasters with different rail geometry and fill. Finite element modeling is used to compute the theoretical natural frequencies and mode shapes of a typical …

Interface Circuit For A Multiple-Beam Tuning-Fork Gyroscope With High Quality Factors, Ren Wang

Mechanical & Aerospace Engineering Theses & Dissertations

This research work presents the design, theoretical analysis, fabrication, interface electronics, and experimental results of a Silicon-On-Insulator (SOI) based Multiple-Beam Tuning-Fork Gyroscope (MB-TFG). Based on a numerical model of Thermo-Elastic Damping (TED), a Multiple-Beam Tuning-Fork Structure (MB-TFS) is designed with high Quality factors (Qs) in its two operation modes. A comprehensive theoretical analysis of the MB-TFG design is conducted to relate the design parameters to its operation parameters and further performance parameters. In conjunction with a mask that defines the device through trenches to alleviate severe fabrication effect on anchor loss, a simple one-mask fabrication process is employed to implement …

Devices And Methods For Electro-Physical Transport Of Dna Across Cell Membranes, Quentin Theodore Aten

Theses and Dissertations

A novel method for charged macromolecule delivery, called nanoinjection, has been developed at Brigham Young University. Nanoinjection combines micro-fabrication technology, mechanism design, and nano-scale electrical phenomenon to transport exogenous DNA across cell membranes on a nano-featured lance. DNA is electrically accumulated on the lance, precision movements of microelectromechanical systems (MEMS) physically insert the lance into cell, and DNA is electrically released from the lance into the cell. Penetration into the cell is achieved through a two-phase, self-reconfiguring metamorphic mechanism. The surface-micromachined, metamorphic nanoinjector mechanism elevates the lance above the fabrication substrate, then translates in-plane at a constant height as the …

Guided Discovery Modules For Statics And Dynamics, Javier A. Kypuros, Horacio Vazquez, Constantine Tarawneh, Robert R. Wrinkle

Mechanical Engineering Faculty Publications and Presentations

Students struggle to conceptualize Engineering Mechanics (i.e. Newtonian Physics, Statics, and Dynamics) fundamentals because they cannot successfully visualize the effects of external loads on physical systems and/or do not intuitively comprehend the static or dynamic response. Traditionally, Engineering Mechanics courses like Statics and Dynamics have been primarily lecture-based with little experimentation. The authors contend that through the use of inquirybased, multimodal activities, lower-division engineering students can more effectively interpret Engineering Mechanics concepts. Instructors must place emphasis on engendering properly conceived engineering intuition and contextualizing concepts and fundamentals. The authors hypothesize that by utilizing often simple, multimodal, inquiry-based exercises, instructors can …

The Inside-Out Classroom: A Win-Win Strategy For Teaching With Technology, Daniel J. Waldorf, Lizabeth Schlemer

Industrial and Manufacturing Engineering

As costs of higher education soar and many universities face uncertain funding models, institutional pressures have increased to improve instructor efficiency. At the same time, U.S. industry leaders and leading educators have called for improvements in engineering education based on more interactive, hands-on student learning experiences. Although many efforts have been made to take advantage of technology to either improve student learning or to maintain student learning while increasing instructor efficiency, few approaches have been shown to improve both learning and efficiency. A teaching method is proposed to improve student learning and increase student satisfaction while also addressing the instructors’ …

Evolving A Summer Engineering Camp Through Assessment, Katherine Chen, Lizabeth Schlemer, Heather Scott Smith, Teana Fredeen

Industrial and Manufacturing Engineering

EPIC (Engineering Possibilities in College) is a one-week summer program for high school students (entering 9th-12th grades) to learn about engineering and experience hands-on labs in a university atmosphere. It's an opportunity for students to explore the different types of engineering available at many universities. The aim of EPIC is to expand the College of Engineering mission to K-12 students: "To educate students for careers of service, leadership and distinction in engineering or other fields by using a participatory, learn by doing, ‘hands-on’ approach".

Design Projects With Out-Of-Town Companies, Lizabeth Schlemer

Industrial and Manufacturing Engineering

The capstone design class in the industrial engineering department at California Polytechnic State University, San Luis Obispo (Cal Poly) includes projects with companies. The projects are large ambiguous facilities design problems that allow students to incorporate many aspects of the IE curriculum. For the past 15 years students have been participating in these projects with local companies. Over the past several years, companies from out of town (200 miles to the north in Mountain View or 200 miles to the south in Oxnard) have participated. These out of town companies have presented certain logistical issues, but they have proven to …

A Simple Lab Project Integrating Theoretical, Numerical, And Experimental Stress Analysis, Peter Schuster

Mechanical Engineering

Learning is enhanced when students consider problems from different perspectives. Unfortunately, in stress analysis courses, the depth of the mathematical analysis and limited time and resources often restricts the focus to traditional closed-form solutions occasionally supplemented with simple demonstrations. In order to enhance student engagement and understanding, a lab mini-project was developed for teaching Castigliano’s method for structural analysis in a stress analysis course.

The mini-project consists of a design evaluation task which is investigated using three different methods: closed-form analysis, finite element analysis, and simple model build and test. The task is to select the better of two alternative …

The Montana Mule: A Case Study In Interdisciplinary Capstone Design, Brock J. Lameres, Ahsan Mian, Hunter Lloyd, Robb Larson

Mechanical and Materials Engineering Faculty Publications

The Montana MULE: A Case Study in Interdisciplinary Capstone Design In May of 2010, NASA held the 1st annual Lunabotics Mining Competition at theKennedy Space Center in Florida. In this competition, 22 teams from across the nationbuilt remote-controlled, robotic excavators to mine lunar regolith simulant. The winnerof the competition was the team who could successfully deposit the most regolith into acollector in 15 minutes. The goal of this competition was to encourage multidisciplinarycapstone design projects. Of the 22 teams that participated in the competition, the“Montana MULE” from Montana State University (MSU) was the only robot tosuccessfully mine the qualifying weight …

Crash Safety In The Introductory Physics Lab, Daniel Ludwigsen, Janet Brelin-Fornari, Joseph Neal

Mechanical Engineering Presentations And Conference Materials

Crash Safety in the Introductory Physics Lab Abstract In the field of vehicle occupant protection and crash safety, the Deceleration Sled offers researchers a controlled, repeatable, and relatively cost-effective means to test interior parts such as safety restraint systems. The sled can accelerate a 2000 lb payload to achieve a speed of 40 mph before a hydraulically controlled deceleration models the deformation of the vehicle structure during a crash. Understanding the dynamics of the sled and interpreting test results incorporates many of the core concepts of a first course in introductory physics. This application of physics principles is the inspiration …

Multi-Disciplinary Project-Based Paradigm That Uses Hands-On Desktop Learning Modules And Modern Learning Pedagogies, William David Schlecht, Bernard J. Wie, Paul B. Golter, Robert F. Richards, Marc Compere, Et Al.

Publications

It has been established that traditional lectures ARE NOT best for student learning – yet that is what the community almost universally does! Furthermore, engineers work in broad multidisciplinary teams while classroom learning is individual and narrow. Yet, educators rarely invest the time and resources necessary to employ such innovations.

In this CCLI type II award we are further refining Desktop Learning Modules (DLMs) within a Cooperative, Hands-on, Active, Problem based, Learning (CHAPL) setting for Chemical, Civil, Mechanical, Bio- and Electrical Engineering courses at a diverse set of institutions, including a community college engaged through a distance learning mode. A …

An Industry-University Partnership Case Study, Peter Schuster

Mechanical Engineering

At many universities, senior undergraduate mechanical engineers work in teams on industry-sponsored capstone design projects. These projects provide an excellent opportunity for students to synthesize their courses, work with the more realistic deadlines and expectations of industry, and interact with company representatives. It also give industrial partners a chance to become educational partners with the university, preview potential new hires, and complete some noncritical projects at low cost.

This paper presents a case study of a successful six-year partnership between the Automotive Bumper Project committee of the American Iron & Steel Institute (AISI) and a mechanical engineering department. The AISI …

Reconfigurable Sampling For Enhanced Energy Efficiency In Power-Constrained Wireless Systems, Timothy Kurp

Master's Theses

Advancement in microelectronics and wireless communications has nurtured the development of low power and low cost wireless systems such as sensor networks. Each node is typically driven by a battery, which has a limited energy capacity that directly constrains node, and network lifetime. This presents a bottleneck for the widespread exploitation of wireless sensing technology. Therefore, improving the energy efficiency of wireless sensing devices is of critical importance and has attracted the attention of the research community.

In this work, a data-driven method has been proposed and systematically investigated. Specifically, this technique reconfigures, in real time, the rate of data …

An Evaluation Of Constitutive Laws And Their Ability To Predict Flow Stress Over Large Variations In Temperature, Strain, And Strain Rate Characteristic Of Friction Stir Welding, Katherine Lynn Kuykendall

Theses and Dissertations

Constitutive laws commonly used to model friction stir welding have been evaluated, both qualitatively and quantitatively, and a new application of a constitutive law which can be extended to materials commonly used in FSW is presented. Existing constitutive laws have been classified as path-dependent or path-independent. Path-independent laws have been further classified according to the physical phenomena they capture: strain hardening, strain rate hardening, and/or thermal softening. Path-dependent laws can track gradients in temperature and strain rate characteristic to friction stir welding; however, path-independent laws cannot. None of the path-independent constitutive laws evaluated has been validated over the full range …

Quantifying Multiple Types Of Damping Acting On Bronze-Wound Guitar Strings, Jonathan Christian

Purdue Polytechnic Masters Theses

The goal of this study was to quantify the contributions of multiple damping types acting on guitar strings for each mode over a wide frequency range so that design variables could be identified to one day create frequency based damping in guitar strings. Structural dynamic testing was used to obtain the time-response of a vibrating string in open air and in a vacuum. From this signal, each harmonic was filtered and the decay envelope was curve-fitted with a function that was a linear summation of decay functions. From the curve-fits, the damping coefficients for aerodynamic, friction, and material damping were …

Numerical Analysis On The Effects Of Blade Loading On Vortex Shedding And Boundary Layer Behavior In A Transonic Axial Compressor, Kenneth Phillip Clark

Theses and Dissertations

Multiple high-fidelity, time-accurate computational fluid dynamics simulations were performed to investigate the effects of upstream stator loading and rotor shock strength on vortex shedding characteristics in a single stage transonic compressor. Various configurations of a transonic axial compressor stage, including three stator/rotor axial spacings of close, mid, and far in conjunction with three stator loadings of decreased, nominal, and increased were simulated in order to understand the flow physics of transonic blade-row interactions. Low-speed compressors typically have reduced stator/rotor axial spacing in order to decrease engine weight, and also because there is an increase in efficiency with reduced axial spacing. …

Experimental Characterization Of Baffle Plate Influence On Turbulent And Cavitation Induced Vibrations In Pipe Flow, Gavin J. Holt

Theses and Dissertations

Turbulent and cavitation induced pipe vibration is a large problem in industry often resulting in pipe failures. This thesis provides an experimental investigation on turbulent flow and cavitation induced pipe vibration caused by sharp edged baffle plates. Due to large pressure losses across a baffle plate, cavitation can result. Cavitation can be destructive to pipe flow in the form of induced pipe wall vibration and cavitation inception. Incipient and critical cavitation numbers are design points that are often used in designing baffle plate type geometries. This investigation presents how these design limits vary with the influencing parameters by exploring a …

Effect Of Molecular Film Thickness On Thermal Conduction Across Solid-Film Interfaces, Zhi Liang, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Brownian Motion and Aggregation of Particles in Nanofluids Often Lead to the Formation of Solid-Film-Solid Structures. the Molecular Thin Film Confined between Nanoparticles May Have Non-Negligible Effects on Thermal Conduction among Nanoparticles. using Nonequilibrium Molecular Dynamics Simulations, We Study Thermal Conduction Across the Ag Particle-Ar Thin-Film Interface. If the Film Contains Only One Molecular Layer, We Find that the Solid-Film Interfacial Thermal Resistance RSF is About 1 Order of Magnitude Smaller Than the Solid-Liquid (Bulk) Interfacial Thermal Resistance RSL. If There Are Two or More Molecular Layers in the Film, It is Shown that RSF Increases Rapidly toward RSL …

A Comparison Of Two Headless Compression Screws For Operative Treatment Of Scaphoid Fractures, Ruby Grewal, Joseph Assini, David Sauder, Louis Ferreira, Jim Johnson, Kenneth Faber

Surgery Publications

PURPOSE: The purpose of this study was to compare the interfragmentary compression force across a simulated scaphoid fracture by two commonly used compression screw systems; the Acutrak 2 Standard and the 3.0 mm Synthes headless compression screw.

METHODS: Sixteen (8 pairs; 6 female, 2 male) cadaver scaphoids were randomly assigned to receive either the Acutrak 2 or Synthes screw with the contralateral scaphoid designated to receive the opposite. Guide wires were inserted under fluoroscopic control. Following transverse osteotomy, the distal and proximal fragments were placed on either side of a custom load cell, to measure interfragmentary compression. Screws were placed …

A Generic Bamboo-Based Carbothermal Method For Preparing Carbide (Sic, B4C, Tic, Tac, Nbc, TiXNb1-XC, And TaX Nb1-XC) Nanowires, Xinyong Tao, Yiping Li, Jun Du, Yang Xia, Yingchao Yang, Hui Huang, Yongping Gan, Wenkui Zhang, Xiaodong Li

Faculty Publications

Finding a general procedure to produce a whole class of materials in a similar way is a desired goal of materials chemistry. In this work, we report a new bamboo-based carbothermal method to prepare nanowires of covalent carbides (SiC and B₄C) and interstitial carbides (TiC, TaC, NbC, Ti_xNb_1−xC, and Ta_xNb_1−xC). The use of natural nanoporous bamboo as both the renewable carbon source and the template for the formation of catalyst particles greatly simplifies the synthesis process. Based on the structural, morphological and elemental analysis, volatileoxides or halides assisted …

Applied Control Strategies At A Cogeneration Plant, Joseph William Burns

Master's Theses

The purpose of this paper is to demonstrate the effectiveness of “classical strategies for dynamic control” on authentic cogeneration processes. These strategies are applied to several processes at the University of Connecticut’s cogeneration plant. Case studies of their applications are presented in this paper. Strategies that are applied include the following:

1) The classical SISO feedback structure

2) The First Order Plus Dead Time (FOPDT) process model

3) The Internal Model Control (IMC) correlations for PI controller tuning

4) Static feed forward with feedback trim

5) Cascade Control

Olympic Bocce Ballers, Steven Erickson, William Haley, Taylor Vaughan

Mechanical Engineering

No abstract provided.

Multiple Motors With Single Controller, Jason Eugene Barbeiro, Benjamin Erik Johnson, Abraham Garza

Mechanical Engineering

No abstract provided.

Blds Heating, Alan Cook, Jon Hsu, Robert Veasey

Mechanical Engineering

Dr. Westphal, a professor at Cal Poly San Luis Obispo, created a boundary layer data system (BLDS). This device was designed to measure the boundary layer over a wing of an airplane during flight. A problem with the BLDS is that at flight altitude of 50,000 ft, the BLDS stops functioning due to the extremely low temperatures.

Team IcePick’s objective was to design, build, and test a device which could provide heat to the BLDS so it can function.  Our team decided to continue with where the previous senior project team had left off and build upon their proof of …

Thrust-Vector Control, Dane Larkin, Harsimran Singh

Mechanical Engineering

Mission Statement

The purpose of this project is to design, build, and test a thrust-vectoring rocket nozzle which will aid in controlling the trajectory of a solid-booster rocket. The system prototype must meet the requirements set forth by the sponsoring enterprise.

The Enterprise

Stellar Exploration is a small space systems technology company located in San Luis Obispo, CA. Stellar Exploration is currently seeking a thrust-vectoring system for its Silver Sword rocket.

Project Scope

The design and analysis portion of this project accounted for a system that would be mounted on to a rocket for operational flight. Therefore, this team has …

Piedras Blancas Light Station Vista Point Improvement Plan, Larissa Heeren, Reuben Juster, Annamarie Usher, John Rossi, Nick Mitchell

Mechanical Engineering

Piedras Blancas Light station Improvement Involved the design of two separate parking lot/vista point plans as well as the creation of a concrete Iron Ranger located near the gift shop on site.