Mechanical Engineering Commons^™

Efficient Rotation Algorithms For Texture Evolution, Mark W. Esty

Theses and Dissertations

Texture evolution is a vital component of many computational tools that link structure, properties and processes of polycrystalline materials. By definition, this evolution process involves the manipulation, via rotation, of points in orientation space. The computational requirements of the current methods being used to rotate crystalline orientations are a significant limiting factor in the drive to merge the texture information of materials into the engineering design process. The goal of this research is to find and implement a practical rotation algorithm that can significantly decrease the computation time required to rotate macroscopic and microscopic crystallographic textures. Three possible algorithms are …

Development Of A Methodology For Numerical Simulation Of A D C Arc Discharge In A Liquid Dielectric, Christopher James Lewis

Theses and Dissertations

The majority of literature regarding the numerical simulation of arc discharges in gaseous environments has used a plasma physics approach. Virtually all simulations treat the discharge as an idealized gaseous plasma, which can be described by temperature, pressure, and electric field. This approach can work well if the media is a shielding gas such as Argon; however, the approach does not work well for processes such as underwater welding, EDM, and underwater discharges used to generate high purity particles. The reason these discharges do not have many extensive simulation efforts as described in the literature is because they occur in …

Energy Dissipation Caused By Asphalt Roadway Gouges For Use In Accident Reconstruction, Charles L. Crosby

Theses and Dissertations

In reconstruction of on-roadway vehicle accidents, roadway surface gouges and the forces and energy attributed to the related vehicle components become important keys to resolving an accurate accident reconstruction. These roadway gouge forces vary depending upon such factors as surface temperature and the velocity and geometry of the gouging mechanism. Accounting for the forces applied to vehicle components and the energy dissipated from such forces can be helpful in accident reconstruction where supporting data exists. This research documents the force necessary to create a given roadway gouge geometry. Controlled pavement gouging tests were performed using roadway surface temperature and gouging …

Discrete Film Cooling In A Rocket With Curved Walls, Jonathan F. Mccall

Theses and Dissertations

This study quantified the effects of discrete wall-based film cooling in a rocket with curved walls. Simulations and experiments showed decreasing with wall radius of curvature, holding jet diameter constant, improves net heat flux reduction (NHFR) and adiabatic effectiveness (η) for 90˚ compound injected cylindrical jets, though η is reduced at the highest curvature. NHFR and η improved further with a high favorable stream-wise pressure gradient (K=2.1x10^-5) at all tested blowing ratios, but were affected little by a high density ratio (DR=1.76) using carbon dioxide as the coolant. Experiments were run at a Reynolds number of 31K and …

Investigation Into Contact Resistance And Damage Of Metal Contacts Used In Rf-Mems Switches, Kevin W. Gilbert

Theses and Dissertations

This research examines the physical and electrical processes involved in lifecycle failure of Microelectromechanical (MEMS) Radio-Frequency (RF) cantilever beam ohmic contact switches. Failures of these switches generally occur at the contact, but complete details of performance of microcontacts are difficult to measure and have not been previously reported. This study investigated the mechanics of microcontact behavior by designing and constructing a novel experimental setup. Three representative contact materials of varying microstructure (Au, Au5%Ru, Au4%V₂O₅) were tested and parameters of contact during cycling were measured. The Au4%V₂O₅, a dispersion strengthened material developed at …

Direct Cooled Ceramic Substrate For Thermal Control Of Automotive Power Electronics, Kirk Townsend Lowe

Doctoral Dissertations

As electric vehicle technology develops, manufacturers would like to move toward hotter coolants for power electronic components to reduce system level costs. Thus, unique designs of inverter designs were sought to enable operation with 105°C coolant. The proposed solution in this research incorporated flow channels into the ceramic layer of the direct-bonded copper substrate typically found in power electronic packages. The focus of this research details the design and analysis of the direct cooled ceramic substrate from the perspective of its thermal performance and innovative packaging concept.

The research was directed to pursue alumina as the substrate ceramic because of …

Formula Sae Interchangeable Independent Rear Suspension Design, Mike Mccune, Daniel Nunes, Mike Patton, Courtney Richardson, Evan Sparer

Mechanical Engineering

The Suspension Solutions design team has completely designed built and tested an independent rear suspension system for the 2008 FSAE car. The car currently features a solid rear axle, and the task of converting it to incorporate an interchangeable rear suspension has been undertaken in order to quantify the advantages and disadvantages of each design philosophy. The car has been properly tested with both the solid axle and independent rear suspension side-by-side, however more testing is suggested. After pushing both setups to their limits on a 50ft diameter skid pad, the test results were quantified, and a final comparison between …

Broccoli Floret Cutter: Gold Coast Packaging, Inc., Sean Stamm, Walter Salguero, Felipe Gomez Jr, Ruben Duenas

Mechanical Engineering

No abstract provided.

Design, Reconstruction And Evaluation Of A Dynamometer For Quarter Scale, Samuel Sanchez

BioResource and Agricultural Engineering

This project discusses the design, reconstruction, and evaluation of a dynamometer. A new test stand for the Quarter Scale team would improve the testing of the engines and the Continuously Variable Transmission (CVT). All the readings will be done electronically in order to provide the most accurate data collection. The dynamometer will be a closed hydraulic system for ease of use. This system will be able to test all of Quarter Scale engines. The data collected will be used to determine which engines are in the best condition, and which may need to be fixed. With the new design, the …

Callaway Golf: Variable Curved Impulse Sealer, Justin Cook, Ben Jones, Sean Reynolds

Mechanical Engineering

No abstract provided.

Boundary Layer Data System (Blds) Heating System, John Hauge, Drew Hutcheson, Paul Scott

Mechanical Engineering

The boundary layer data system (BLDS) is the result of a collaborative effort between Dr. Westphal, a researcher and instructor at Cal Poly, and Northrop Grumman. The BLDS is capable of measuring the boundary layer profile and characteristics of flow over aerodynamic surfaces and is intended for high altitude, high speed use. The instruments inside the BLDS malfunction at the low temperatures present when operating in flight at altitudes above 30,000 ft. To solve this problem, analysis was done on the existing BLDS which determined the heating requirements, around 50 watts, needed to keep the internal temperature within the rated …

Two-Material Cylinder Stress Response Software, Katherine Gage, Matt Highstreet, Liz Del Cid

Mechanical Engineering

No abstract provided.

Module Cover Conductivity Enhancement, Niles Dhanens, James Fortner

Mechanical Engineering

A clam shell module cover for printed circuit boards (PCB) has been designed for use in Boeing’s AECM cabinet. The cover utilizes materials with high thermal conductivity and cools the PCB by conducting the heat to a cold plate interface. Materials were compared and aluminum 6061-T6, aluminum 3003, and annealed pyrolytic graphite (APG) were chosen. A prototype was built and tested using aluminum 6061-T6 which was able to dissipate 57.7% of the projected wattage. Issues may include unforeseen complications in assembly along with components performing at lower levels than specified by manufacturers. The APG prototype was unable to be tested …

Pump Sequencing Optimization, John S. Allan, Kyle J. Nekimken, Spencer B. Weills

Mechanical Engineering

The purpose of this document is to demonstrate the design, production, and testing of optimum pump sequencing logic for variable frequency drive (VFD) pumps in commercial heating ventilating and air conditioning (HVAC) systems. The product will be developed by Pump Efficiency Solutions (PES), which is a group of Cal Poly students working on their senior project. The product is being developed for Trane, an industry leader in large scale HVAC systems. MATLAB™, Microsoft Excel, Pump System Improvement Modeling Tool™ (PSIM), and fluid mechanics hand calculations were used during software development. Next, we converted the program into Trane’s graphical programming language …

Hydraulic Hand Press Final Project Report, Nathaniel Marc Brown, Matthew Thomas Knorr

Mechanical Engineering

This report provides a thorough description of the design of a hydraulic hand-operated press by mechanical engineering students at California Polytechnic State University, San Luis Obispo, California, for the Estrella Warbirds Museum in Paso Robles, California. It begins with research into hydraulic operations, a brief study of fluid power and incompressible fluids, and a look into existing products. Specified customer requirements stipulate the loading and general size constraints. As part of the project, a schedule is laid out following industry techniques. Brainstorming and decision matrices are utilized as well, conveying our design process. A basic structure is developed using strength …

Indirect Pipe Pressure Measurement, Clayde Barkley, Mikel Betts, Anthony Olay

Mechanical Engineering

Statement of Confidentiality The complete senior project report was submitted to the project advisor and sponsor. The results of this project are of a confidential nature and will not be published at this time.

Chip Removal Tool Project, Brett Mori, John Cote, Kyle Rowland, Micah Wells

Mechanical Engineering

The Cal Poly senior project team worked with Helical Products Inc. to develop an automated method for removing swarf and chip buildup from the drill bits of their CNC milling machines. The removal methods in this report were designed for and tested using a Fanuc Robodrill while keeping the potential in mind for their use in other CNC milling machines. After extensive background research, preliminary and prototype design and testing the final chosen design is shown below. The cleaning device is made from flexible sheet metal and placed on a fixture that occupies one of the two pallet locations inside …

Air Cooling For Aecm Module, Final Project Report, Kevin Whipp, Abraham Bruno Caulk

Mechanical Engineering

Advancements in electronics have created the need for improved cooling standards. The AECM standard, created to replace the antiquated ARINC 600 specification for aircraft, draws inspiration from a cooling specification known as VITA 48.2. The ARINC standard is in early stages of development and this project researches the feasibility of using air as a convective fluid instead of a liquid, the fluid used in the VITA specification.

A performance factor calculated from the ratio of the heat dissipated by convective heat exchanger plates over the power used to cause forced convective flow over said plates helps to quantify the effectiveness …

A Fast Nir Spectrometer For Examining Explosive Events: Emission Of Petn Based Explosives And H2O Absorption Method Feasibility, Scott Piecuch

Master's Theses (2009 -)

The chemical dynamics and decomposition pathways of explosive materials are not entirely known. Measurements of chemical transients during explosive events can lead to enhanced knowledge of the detailed chemistry and eventually control of the end products; however, these measurements are often difficult to obtain due to fast time scales and harsh environments. Optical diagnostics present fast-response, minimally invasive methods for resolving properties in detonation environments and previous fast spectroscopic measurements have been recorded in the ultra-violet and visible regions. This work extends the range of such measurements to the near-infrared (NIR) through the development of a fiber-coupled NIR spectrometer utilizing …

Best-In-Class Global Bumper Reinforcement Beam, Garret Anthony Bautista, Chad Anthony Hardin, Benjamin Ray Taylor

Mechanical Engineering

Modern bumper systems are governed by laws and regulations imposed separately by various countries. Today, the regulations in China, North America, and Europe are becoming more similar, but there is not a widely accepted bumper reinforcement that meets the requirements of all markets around the globe.

A universal bumper reinforcement beam incorporating Plug-n-Play techniques was developed to meet and exceed all testing requirements and performance standards of each country. These Plug-n-Play techniques consist of adding energy absorbing attachments to the front of a base bumper beam. Simple beam analysis and FEA were the primary analysis tools in the development of …

Supermileage Team - Urban Concept Competition Vehicle Chassis Design Report, Andrew Allport, Kevin Braico, Kevin Charles, George Kyi, William Lai

Mechanical Engineering

This research and design project was proposed by the Cal Poly Supermileage team. They have requested for our team to design an Urban Concept car, a new category of vehicles to compete for fuel efficiency in the Shell Eco-marathon in 2010. The primary focus of our team is in the design and construction of a chassis the Supermileage team can use for the 2010 competition in Fontana, CA. This design must meet dimensional and functional requirements set by Shell while being designed to maximize efficiency in the competition.

There were various chassis concepts under consideration that would possibly work for …

Laboratory Generation And Physics Of Propagation Of Solitary Waves And Water Surface Depressions, Siamak Malek Mohammadi

All Dissertations

Solitary waves and water surface depressions are generated using a piston-type wavemaker. Different aspects of their propagation including profile evolution, establishment rate, stability, and celerity are examined experimentally.
Traditionally, solitary waves are generated in laboratory set-ups using a methodology developed by Goring (1979) that considers a wave of permanent form during the generation process. A New methodology for generation of solitary waves using piston-type wavemakers is proposed by considering the evolving nature of the wave during generation phase. The capability of the New methodology in generation of solitary waves is assessed by conducting a series of laboratory experiments in water …

Development Of An Air-Cycle Environmental Control System For Automotive Applications, Christopher James Forster

Master's Theses

An air‐cycle air conditioning system, using a typical automotive turbocharger as the core of the system, was designed and tested. Effects on engine performance were kept to a minimum while providing the maximum amount of cooling possible and minimizing weight and space requirements. A test stand utilizing shop compressed air was developed to measure component performance. An unmodified automotive turbocharger was tested initially as a baseline in a Reversed‐Brayton Cycle air cooling system. Once the baseline was established, another aircycle machine, assembled from commercial turbocharger components chosen individually to optimize their performance for cooling purposes, was tested to improve the …

The Cryogenic Bonding Evaluation At The Metallic-Composite Interface Of A Composite Overwrapped Pressure Vessel With Additional Impact Investigation, Eric A. Clark

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A bonding evaluation that investigated the cryogenic tensile strength of several different adhesives / resins was performed. The test materials consisted of 6061 aluminum test pieces adhered to a wet-wound graphite laminate in order to simulate the bond created at the liner-composite interface of an aluminum lined composite overwrapped pressure vessel. It was found that for cryogenic applications, a flexible, low modulus resin system must be used. Additionally, the samples prepared with a thin layer of cured resin – or prebond – performed significantly better than those without. It was found that it is critical that the prebond surface must …

Parallelization Of Performance Limiting Routines In The Computational Fluid Dynamics General Notation System Library, Kyle Horne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Computational Fluid Dynamics General Notation System provides a unified way in which computational fluid dynamics data can be stored, but does not support the parallel I/O capabilities now available from version five of the Hierarchical Data Format library which serves as a back end for he standard. To resolve this deficiency, a new parallel extension library has been written and benchmarked for this work which can write files compliant with the standard using parallel file access modes. When using this new library, the write performance shows an increase of four-fold in some cases when compared to the same hardware …

Simulation, Synthesis, And Characterization Of Hydrogels And Nanocomposite Gels., Kamleshkumar J. Suthar

Dissertations

Stimuli-responsive gels are three-dimensional, cross-linked polymeric materials that undergo large physical change in response to the environmental stimuli, like temperature, pH, electrical potential, and irradiation. Ferrogels are colloidaldispersion of magnetic nanoparticles in the hydrogel network. The magnetic nanoparticles are attached to the polymeric network by different adhesive forces; as a result, it becomes sensitive to the applied magnetic field.

The main objective of this research is the simulation, synthesis, and characterization of the hydrogel and ferrogel. Simulation of the hydrogel response was performed for various environmental stimuli using a multiphysics finite element analysis software, COMSOL. The pH and electrical response …

A Study On Gas Penetration And Fingering Behavior In Injection Molding Of Polymer And Powder Metal Feedstock, Edna I. Orozco

Theses and Dissertations - UTB/UTPA

The effect of processing variables on the level of gas penetration in parts fabricated by gas-assisted injection molding from two different materials was compared. The materials used were polypropylene and stainless steel powder metal/thermoplastic feedstock. Software simulation and physical experiments were conducted. Taguchi analysis was used to reduce the number of experiment trials and to find the optimum processing conditions. Four different variables were changed using nine different combinations. The processing variables are the pressure, the delay time before gas is injected, the temperature of the material injected, and the amount of the material injected. The results showed that the …

An Experimental Study Of Potential Residential And Commercial Applications Of Small-Scale Hybrid Power Systems, Michael Anthony Acosta

Theses and Dissertations - UTB/UTPA

The research presented in this thesis provides an understanding of small-scale hybrid power systems. Experiments were conducted to identify potential applications of renewable energy in residential and commercial applications in the Rio Grande Valley of Texas. Solar and wind energy converted into electric energy was stored in batteries and inverted to power common household and commercial appliances. Several small to medium size hybrid power systems were setup and utilized to conduct numerous tests to study renewable energy prospects and feasibility for various applications. The experimental results obtained indicate that carefully constructed solar power systems can provide people living in isolated …

Cross Sections Used To Elucidate Differences In Wavelet Transforms Of Ground Force Reactions, Wesley John Orme

Boise State University Theses and Dissertations

A study done for the Centers for Disease Control (CDC) found that over 50% of sports related injuries are to the lower extremities [1] with additional studies indicating that females, adolescent through collegiate, have a higher rate of lower extremity sports related injuries than males [2-4]. Conditions surrounding non-contact injuries can be analyzed using ground reaction force (GRF) data from force plates during unanticipated single leg drops, however, the expected gender differences in GRF may not be apparent when viewing data independently in the time or frequency domains.

Graphing the results of a wavelet transform, currently used by scientific, medical, …

Computational Fluid Dynamics Modeling Of Atmospheric Flow Applied To Wind Energy Research, Alan Russell

Boise State University Theses and Dissertations

High resolution atmospheric flow modeling using computational fluid dynamics (CFD) has many applications in the wind energy industry. A well designed model can accurately calculate wind speed, direction, and turbulence at any point in a wind farm using data from a fixed location source. The model can extend point source data over an area of several square kilometers, or map terrain influenced microclimates using remote wind data. A local flow model is critical for wind resource site assessment, and for optimizing wind farm turbine layout for maximum power production. A CFD simulation of an operating wind farm, coupled with a …