Mechanical Engineering Commons^™

The Sources Of Heat Generation In Vibrothermography, Jeremy Renshaw, John Chen, Stephen Holland, R. Bruce Thompson

Mechanical Engineering

Vibrothermography, or sonic IR, is a nondestructive evaluation technique used to find surface and near surface defects—such as cracks and delaminations—through observations of vibration-induced heat generation. This method has significant interest as an industrial inspection method, however, a lack of understanding of the fundamental physics governing the heat generation process has limited its application despite extensive theoretical, numerical simulation, and experimental work. Significant theoretical and numerical simulation work has been performed, but has yet to be rigorously verified experimentally. This paper presents experimental verification of the sources of heat generation in vibrothermography; specifically friction, plasticity, and viscoelasticity. Specific experimental evidence …

Strength Of Polycrystalline Ceramics Under Shock Compression, Jianbin Zhu

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Determinations of Some polycrystalline ceramics’ strength properties and inelastic deformation mechanisms in the shocked state are critically important to the design and optimization of armor structures involving these materials. In this work, multiscale modeling and simulations have been carried out to study strength of the effects of polycrystalline microstructure, crystal anisotropy, porosity, and their interactions with microscopic deformation/damage mechanisms on the responses of several polycrystalline ceramics under shock compression and to extract their shock strengths from the wave profiles measured in the related plate impact shock wave experiments.

With a mesoscopic computational model, the roles of intragranular microplasticity and deformation …

Design, Analysis, And Testing Of In Vivo Surgical Robots, Tyler David Wortman

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Advances in technology have shaped the history of surgical procedures. Recent developments have allowed surgical procedures to become less invasive than traditional open procedures. The transition to Minimally Invasive Surgery (MIS) has resulted in decreased recovery times, improved cosmetic results, and reduced costs. For these reasons, there is interest in further reducing the invasiveness of surgical procedures by accessing the abdominal cavity through a single incision, such as with Laparoendoscopic Single-Site (LESS) surgery. Added complexities, such as unintuitive controls and limited dexterity, prevent the widespread adoption of LESS for complex surgical procedures. Multi-functional in vivo surgical robots have been designed …

Feasibility Analysis And Concept Development Of A Crash Cushion Diaphragm Structure For High-Speed Race Tracks, Curt Lee Meyer

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

A new diaphragm and dual guide rail system was designed for use in a crash cushion for high-speed race tracks. These structural components were designed to provide sufficient lateral support to redirect impacting vehicles and compress the energy-absorbing elements of the crash cushion. The primary design criteria stated that the diaphragm/guide rail system should be capable of withstanding a 100-kip lateral impact load. The guide rail was to be configured in order to not require replacement after a design impact event. Initial design and modeling resulted in two candidates for guide rail sections which were evaluated during physical testing. The …

Understanding Svocs, Ying Xu, Jianshun Zhang

Mechanical and Aerospace Engineering - All Scholarship

Semi-volatile organic compounds (SVOCs) are an important class of indoor pollutants that are of great health concern. However, they have not received much attention within the ASHRAE community. This column provides an overview of the sources, sinks, transport mechanisms, and potential health effects, and discusses how HVAC systems may affect occupants’ exposure to SVOCs.

Dynamic Botanical Filtration System For Indoor Air Purification, Zhiqiang Wang

Mechanical and Aerospace Engineering - Dissertations

A dynamic botanical air filtration (DBAF) system was developed, tested and modeled for indoor air purification. The DBAF system consisted of an activated-carbon/hydroculture-based root bed for potted-plant, a fan for driving air through the root bed for purification, and an irrigation system for maintaining proper moisture content in the root bed. Results from test conducted in a full-scale open office space indicated that the filtration system had ability to supply clean air equivalent to 80% of required outdoor air supply for the space. The DBAF was effective for removing both formaldehyde and toluene at 5 to 32% volumetric water content …

In Vitro Study Of Fluid Diodes In The Pulmonary Valve Position, John Porcher

All Theses

Every year many people suffer from severe chronic pulmonary insufficiency. Problems that can be incurred include the valve becoming stenotic, where it inhibits antegrade flow, and incompetent, allowing retrograde flow. When either of these conditions occurs with great severity, it is often necessary for the native valve to be replaced. There are no acceptable, permanent solutions currently available for a pulmonary valve replacement. Previous research, based on regurgitant fraction and transvalvular gradient, has indicated that a fluid diode could possibly serve as a permanent valve replacement solution. This study investigated the effectiveness of a diode to reduce the workload of …

An Early Warning Monitoring System For Cnc Spindle Bearing Failure, Andrew Werner

All Theses

Equipment employed in a manufacturing environment must be able to operate as long as possible having as little downtime as possible. Therefore, maintenance is crucial in order to allow for the equipment to perform its designated tasks without failure, especially on critical systems. In a CNC machine, if the spindle fails, the machine is useless. Having the ability to detect spindle degradation to the point where a replacement spindle installation can be planned, via condition monitoring, is invaluable to a manufacturer who utilizes these types of machines.
An early warning monitoring system for CNC spindle bearing failure has been developed …

Fabrication And Characterization Of Multi-Functional Non-Spherical Particles Via Mechanical Deformation, Venkata Shilpa Varahagiri

All Theses

Nanoparticles bridge the gap between bulk materials and molecules. They possess exciting but contrasting mechanical, chemical, magnetic and optical properties when compared to their bulk counterparts due to their shape and size. When the size of noble metal nanoparticles is reduced to less than the wavelength of light, the particles intensely absorb and scatter light at wavelengths that depend on the particle size, shape, and local dielectric environment due to Localized Surface Plasmon Resonance (LSPR) modes. Recently, plasmonic particles have been used in a wide variety of sensor and optical device applications including immunoassays and surface enhanced Raman spectroscopy substrates. …

Product And Process Based Assembly Time Estimation In Engineering Design, Michael Miller

All Theses

This thesis presents the research and development of two assembly time estimation techniques for the automotive industry. Both of these techniques are capable of being implemented early in the product life-cycle of a vehicle and require information available in this phase. Currently, assembly time estimation is performed after production has begun and is a tedious manual process requiring hours of motion-time method studies for each assembly activity. The techniques proposed in this thesis can both be performed prior to the start of production and are capable of being performed automatically after the initial mapping.
The first assembly time estimation technique …

Development Of Spray Cooling For High Heat Flux Electronics, Jeremy Scott Junghans

Graduate Theses and Dissertations

The thermal demands of modern day electronic systems require innovative thermal solutions. Spray cooling has proven to be able to cool heat fluxes orders of magnitude higher than traditional cooling methodologies. This work includes a comparison of spray cooling to standard thermal management methodologies. Key system parameters and considerations are discussed. The properties of available packaging materials and their effect on the reliability of a spray cooled system are presented. Parameters such as fluid temperature, droplet size, fluid velocity and flow rate all directly impact performance and are detailed in this work. Finally, results from of a wide range of …

Wireless Solar-Powered Thermal Imaging Camera, Andy Bonk, Billy Mcvicker, Jacob Richardson

Mechanical Engineering

Creation of a mounted wireless self-powered thermal imaging camera system.

Robotic Turret, Daniel Romero, Matthew (Matt) Martelle, Scott Mullens, Rachel Diamant

Mechanical Engineering

No abstract provided.

Ergonomic Lifter, Bejan Brian Banihashemi, Dylan James Schockemoehl, Andrew Ouellet

Mechanical Engineering

No abstract provided.

Wiihopp, Jeff Christian, Ben Hoselton, Derek Simon

Mechanical Engineering

Childhood obesity is becoming a growing problem in the United States. According to the CDC, childhood obesity has more than tripled in the past 30 years [7]. It can lead to health problems previously reserved for adults, such as diabetes, high blood pressure, and high cholesterol. For the team WiiHopp project, we plan to turn a JumpSport mini-trampoline into a controller for the Nintendo Wii console. The hope is to help turn the problem of video games and the laziness surrounding them into an active solution to combat the problem of childhood obesity.

Our goal is to produce an add-on …

Access|Closure Balloon Catheter Redesign Project, Keenan Bamburg, Yvette Castillo, Elizabeth Eskildsen

Mechanical Engineering

No abstract provided.

Strider, George Cummings, Brian Kreidle, Ricky Lee, Clark Steen

Mechanical Engineering

No abstract provided.

Investigation On Interactions Of Unsteady Wakes And Film Cooling On An Annular Endwall, Matthew J. Golsen

HIM 1990-2015

In recent decades, greater interest in the effect of rotational wakes on gas turbine film cooling applications has produced increasing numbers of studies on these unsteady phenomena. Wakes are primarily shed from upstream components such as transition duct walls, stator vanes, and rotors. Studies have shown that in areas of unsteady flow, the best performing parameters in conventional steady investigations may not be the best for unsteady applications. One common method of modeling the unsteady wake interaction in subsonic flows is the use of spoke wheel type wake generators using cylindrical rods to produce the velocity detriment and local increase …

High Temperature Thermodynamic Properties Of Znte(S), Robert F. Brebrick

Mechanical Engineering Faculty Research and Publications

We have gathered the partial pressure, Knudsen cell, and emf measurements on ZnTe(s) from which the Gibbs energy of formation can be calculated. Published partial pressures of diatomic tellurium have been adjusted to take account of a subsequently published third law analysis of tellurium. The equation used to calculate the total pressure from the rate of mass loss from an extensive set of Knudsen cell measurements has been corrected to give a 5% increase in total pressure and the Gibbs energy of formation has been recalculated. A high temperature heat capacity for ZnTe(s) has been selected from the published data. …

Efficient Uncertainty Quantification In Multidisciplinary Analysis Of A Reusable Launch Vehicle, Benjamin R. Bettis, Serhat Hosder, Tyler Winter

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The objective of this study was to apply a recently developed uncertainty quantification framework to the multidisciplinary analysis of a reusable launch vehicle (RLV). This particular framework is capable of efficiently propagating mixed (inherent and epistemic) uncertainties through complex simulation codes. the goal of the analysis was to quantify uncertainty in various output parameters obtained from the RLV analysis, including the maximum dynamic pressure, cross-range, range, and vehicle takeoff gross weight. Three main uncertainty sources were treated in the simulations: (1) reentry angle of attack (inherent uncertainty), (2) altitude of the initial reentry point (inherent uncertainty), and (3) the Young's …