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Full-Text Articles in Mechanical Engineering

The Development And Fabrication Of A Modular Vertical Reciprocating Conveyor System For The Transportation Of Materials To And From A Mezzanine., Matthew Paul Crum Dec 2011

The Development And Fabrication Of A Modular Vertical Reciprocating Conveyor System For The Transportation Of Materials To And From A Mezzanine., Matthew Paul Crum

Electronic Theses and Dissertations

The purpose of this developmental project was to design and fabricate a vertical reciprocating conveyor in order to eliminate the process of manually carrying 27 pound containers of plastic resin up and down a flight of offset space saver stairs. This project took place and was built for Phoenix Closures Incorporated. The conveyor was designed and built in house because there are no commercially available vertical reciprocating conveyors available that meet the necessary requirements.

The capabilities of the proposed vertical reciprocating conveyor are not limited to the carrying of the containers but designed to carry vacuum cleaners, tool boxes, and …


Innovative Design: Design Of A Press System And Molds To Produce A Skateboard Deck., George William Linke Dec 2011

Innovative Design: Design Of A Press System And Molds To Produce A Skateboard Deck., George William Linke

Electronic Theses and Dissertations

Skateboarding is a passion for many people. Homemade skateboard machinery has been fabricated throughout the country. While the demand for skateboards is steady; there is a steady growth in the homemade skateboard deck market. The desire to create a one of a kind deck that expresses a person's individualism is growing. This applied research and development effort - designing and fabricating a fluid powered press system and 2-part mold assembly for forming glue up laminations for skateboard decks - is an attempt to gain understanding of the different phases of the product design process.


Development Of A Scale Model Wind Turbine For Testing Of Offshore Floating Wind Turbine Systems, Heather Rae Martin Dec 2011

Development Of A Scale Model Wind Turbine For Testing Of Offshore Floating Wind Turbine Systems, Heather Rae Martin

Electronic Theses and Dissertations

This thesis presents the development of a 1/50th scale 5 MW wind turbine intended for wind and wave basin model testing of commercially viable floating wind turbine structures. The design is based on a popular 5 MW wind turbine designed by the National Renewable Energy Laboratory (NREL) commonly utilized in numerical modeling efforts. The model wind turbine is to accompany generic floating model platforms for basin model testing. The ultimate goal of the model development testing program is to collect data for validating various floating wind turbine simulation codes such as those developed by NREL. This thesis will present an …


Heat Transfer And Friction Augmentation In A Narrow Rectangular Duct With Symmetrical And Non-Symmetrical Wedge-Shaped Turbulators, Michelle Valentino Jan 2011

Heat Transfer And Friction Augmentation In A Narrow Rectangular Duct With Symmetrical And Non-Symmetrical Wedge-Shaped Turbulators, Michelle Valentino

Electronic Theses and Dissertations

The need for cleaner and more fuel efficient means to produce electricity is growing steadily. Advancements in cooling technologies contribute to the improvements in turbine efficiency and are used for gas turbines and for power generation in automotive, aviation, as well as in naval applications, and many more. Studies introducing turbulators on walls of internal cooling channels, which can be applied to hot gas components and in recuperative heat exchangers, have been reviewed for their ability to promote heat transfer in the channel while observing pressure loss caused by adding the features. Several types of turbulators have been studied; ribs, …


Measurements In Air-Water Bubbly Flow Through A Vertical Narrow High-Aspect Ratio Channel, Benjamin R. Patrick Jan 2011

Measurements In Air-Water Bubbly Flow Through A Vertical Narrow High-Aspect Ratio Channel, Benjamin R. Patrick

Electronic Theses and Dissertations

Two-Phase bubbly flows are encountered in a wide range of industrial applications, particularly where phase changes occur as seen in high performance heat exchangers and boiling reactors for power generation. These flows have been extensively studied in channels with circular geometries using air-water flows, though little data exists for flows through narrow rectangular channels. Measurements in thin geometries are particularly challenging since large bubbles bridge the gap, and it is difficult to compare point measurements with photographic techniques. The objective of this study is to explore the abilities of hot-film anemometry and high speed photography for taking measurements in a …


High Frequency Thermally Actuated Single Crystalline Silicon Micromechanical Resonators With Piezoresistive Readout, Amir Rahafrooz Jan 2011

High Frequency Thermally Actuated Single Crystalline Silicon Micromechanical Resonators With Piezoresistive Readout, Amir Rahafrooz

Electronic Theses and Dissertations

Over the past decades there has been a great deal of research on developing high frequency micromechanical resonators. As the two most common and conventional MEMS resonators, piezoelectric and electrostatic resonators have been at the center of attention despite having some drawbacks. Piezoelectric resonators provide low impedances that make them compatible with other low impedance electronic components, however they have low quality factors and complicated fabrication processes. In case of electrostatic resonators, they have higher quality factors but the need for smaller transductions gaps complicates their fabrication process and causes squeezed film damping in Air. In addition, the operation of …


Label-Free Biochemical Recognition Using Mems Resonators For Microarray Technology, Babak Tousifar Jan 2011

Label-Free Biochemical Recognition Using Mems Resonators For Microarray Technology, Babak Tousifar

Electronic Theses and Dissertations

Highly sensitive biosensors capable of detecting and characterizing smallest quantities of cellular and molecular targets are needed in pharmaceutical and medical diagnostics industries. In this work, the importance of biological target recognition specifically proteins through microarray technologies has been discussed and the most successful tools and techniques have been studied. Moreover, a thermally actuated Micro Electro-Mechanical Systems (MEMS) resonator has been demonstrated and fabricated in this work as an accurate, reliable and low cost biotechnology tool. As a proof of concept, amine to epoxide coupling of octadecylamine to functionalized silicon dioxide surface have been shown through resonator frequency monitoring. The …


An Integrated Platform To Increase The Range/Endurance Of Unmanned Helicopters, Roy Godzdanker Jan 2011

An Integrated Platform To Increase The Range/Endurance Of Unmanned Helicopters, Roy Godzdanker

Electronic Theses and Dissertations

Class I (kg) autonomous helicopters are becoming increasingly popular for a wide range of non-military applications such as, surveillance, reconnaissance, traffic monitoring, emergency response, agricultural spraying, and many other "eye in the sky" missions. However, an efficient landing/takeoff platform with refueling/recharging capabilities has not yet been developed to increase the endurance and decrease the cost for Class I helicopters.

This dissertation presents a three-prong approach for increasing the range and endurance of Class I autonomous helicopters, which will then spur demand by non-military organizations wanting to take advantage of such capabilities and, therefore, drop their price. The proposed Intelligent Self-Leveling …


Effects Of A Heated Turbulent Boundary Layer On Surface Pressure Fluctuations, David William Rich Jan 2011

Effects Of A Heated Turbulent Boundary Layer On Surface Pressure Fluctuations, David William Rich

Electronic Theses and Dissertations

Recent work has shown that spatial correlation of surface pressure fluctuations in a fully turbulent atmospheric boundary layer (ABL) can give information about the velocity field and turbulence. This is of particular importance to the future of wind energy to predict the incoming velocity flow field of wind turbines so as to actively control them for peak operating efficiency and damage reduction. All of the environmental effects on the surface pressure fluctuations need to be fully understood before a suitable flow prediction algorithm can be constructed. One such environmental effect which has not been previously studied is the effect of …


Quantification Of An Ultrasound Test Apparatus And Its Potential Use To Control Nuisance Species In Commercial Aquaculture Settings, Bradley T. Goodwiller Jan 2011

Quantification Of An Ultrasound Test Apparatus And Its Potential Use To Control Nuisance Species In Commercial Aquaculture Settings, Bradley T. Goodwiller

Electronic Theses and Dissertations

As one step in the investigation of using acoustics to improve aquaculture production, work was pursued on the possible use of ultrasound to control the Bolbophorus trematode in commercial catfish ponds. The trematode population can be controlled by eliminating the host ram's horn snail via exposure to high amplitude ultrasound. Initial laboratory tests indicated that a commercially available sonicator (operating at 20 kHz) is capable of killing individual snails in fish tanks. More thorough testing indicated efficiency rates of approximately 35% on batches of 10 snails. In addition to the snails killed immediately, there was evidence that the sonication technique …


Processing Parameters And Chamber Length Impact On Detached Die And Attached Die Resin Injection Pultrusion, Dinesh Raj Palikhel Jan 2011

Processing Parameters And Chamber Length Impact On Detached Die And Attached Die Resin Injection Pultrusion, Dinesh Raj Palikhel

Electronic Theses and Dissertations

Injection pultrusion is an efficient and highly automated continuous process for high-quality, low-cost, high-volume manufacturing of composites. The main objective of this study is to analyze "attached die configuration" and "detached die configuration" for the better injection pultrusion process. In this work the impact of various processing parameters on complete wet out of composite parts is investigated in the attached die and detached die injection pultrusion with various chamber length considerations. The various processing parameters considered are pull speed, fiber volume fraction, resin viscosity, injection port location and compression ratio. 3-D finite volume technique is used to simulate the liquid …


Development Of An Astm Draft Standard For The Elevated Temperature Moisture Conditioning Of Pultruded Fiber Reinforced Polymer Composites, Tunji Adejumo Jan 2011

Development Of An Astm Draft Standard For The Elevated Temperature Moisture Conditioning Of Pultruded Fiber Reinforced Polymer Composites, Tunji Adejumo

Electronic Theses and Dissertations

No abstract provided.


Study Of High Efficiency Micro Thermoelectric Energy Harvesters, Steven Michael Pedrosa Jan 2011

Study Of High Efficiency Micro Thermoelectric Energy Harvesters, Steven Michael Pedrosa

Electronic Theses and Dissertations

Thermal energy sources, including waste heat and thermal radiation from the sun, are important renewable energy resources. Thermal energy can be converted into electricity by thermoelectric phenomena; the thermoelectric phenomena can also be operated in reverse when provided an electric current, producing a temperature gradient across the device. Thermoelectric devices are scalable, renewable, and cost effective products that offer capabilities to harness waste heat or environmental heat sources, and convert the captured heat into usable electricity. The operating principle of a thermoelectric device requires that a temperature gradient be present across the device, which induces the flow of electrons from …


Modeling Of Thermal Properties Of Fiber Glass Polyester Resin Composite Under Thermal Degradation Condition, Marvin S. Tsoi Jan 2011

Modeling Of Thermal Properties Of Fiber Glass Polyester Resin Composite Under Thermal Degradation Condition, Marvin S. Tsoi

Electronic Theses and Dissertations

Composites, though used in a variety of applications from chairs and office supplies to structures of U.S. Navy ships and aircrafts, are not all designed to hold up to extreme heat flux and high temperature. Fiber-reinforced polymeric composites (FRPC) have been proven to provide the much needed physical and mechanical properties under fire exposure. FRPC notable features are its combination of high specific tensile strength, low weight, along with good corrosion and fatigue resistance. However FRPC are susceptible to thermal degradation and decomposition, which yields flammable gas, and are thus highly combustible. This property restricts polymeric material usage. This study …


Purge And Secondary Flow Interaction Control By Means Of Platform Circumferential Contouring, Melissa Harris Jan 2011

Purge And Secondary Flow Interaction Control By Means Of Platform Circumferential Contouring, Melissa Harris

Electronic Theses and Dissertations

This study presents an attempt to reduce the losses produced by the purge flow in a turbine stage by incorporating circumferential platform contouring. Two contours are proposed and compared against a baseline at different levels of swirl. The computational simulations were performed using a RANS three-dimensional Computational Fluid Dynamics code with the Shear Stress Transport turbulence model. The results of steady simulations demonstrate that for the first contour, when the flow is swirled to 50% of the rim speed, the purge flow exits the cavity with less cross flow. This in turn reduces the strength of the passage vortex. However, …


Design And Optimization Of A Wave Energy Harvester Utilizing A Flywheel Energy Storage System, Steven Alexander Helkin Jan 2011

Design And Optimization Of A Wave Energy Harvester Utilizing A Flywheel Energy Storage System, Steven Alexander Helkin

Electronic Theses and Dissertations

This thesis details the design and optimization of a buoy used to collect renewable energy from ocean waves. The proposed buoy is a point absorber—a device that transforms the kinetic energy of the vertical motion of surface waves into electrical energy. The focus of the research is on the mechanical system used to collect the energy, and methods to improve it for eventual use in an actual wave energy harvester. A flywheel energy storage system was utilized in order to provide an improved power output from the system, even with the intermittent input of force exerted by ocean waves. A …


Heat Transfer In A Coupled Impingement-Effusion Cooling System, Mark W. Miller Jan 2011

Heat Transfer In A Coupled Impingement-Effusion Cooling System, Mark W. Miller

Electronic Theses and Dissertations

Gas turbine engines are prevalent in the today’s aviation and power generation industries. The majority of commercial aircraft use a turbofan gas turbine engines. Gas turbines used for power generation can achieve thermodynamic efficiencies as high as 60% when coupled with a steam turbine as part of a combined cycle. The success of gas turbines is a direct result of a half century’s development of the technology necessary to create such efficient, powerful, and reliable machines. One key area of technical advancement is the turbine cooling system. In short, increasing the turbine inlet temperature leads to a rise in cycle …


Multi-Sensor Optimization Of The Simultaneous Turning And Boring Operation, Erick Johan Deane Jan 2011

Multi-Sensor Optimization Of The Simultaneous Turning And Boring Operation, Erick Johan Deane

Electronic Theses and Dissertations

To remain competitive in today’s demanding economy, there is an increasing demand for improved productivity and scrap reduction in manufacturing. Traditional manufacturing metal removal processes such as turning and boring are still one of the most used techniques for fabricating metal products. Although the essential metal removal process is the same, new advances in technology have led to improvements in the monitoring of the process allowing for reduction of power consumption, tool wear, and total cost of production. Replacing used CNC lathes from the 1980’s in a manufacturing facility may prove costly, thus finding a method to modernize the lathes …


Fatigue Testing And Computational Analysis Of A Spinal Implant, Timothy Helton Jan 2011

Fatigue Testing And Computational Analysis Of A Spinal Implant, Timothy Helton

Electronic Theses and Dissertations

The following study investigates the fatigue behavior of a spinal implant developed by Synthes, Inc. to provide stability and off load pressure from the discs in the lumbar region. The installation process for the StenoFix design utilizes plastic deformations to customize the device to each individual patient, but also has potential to degrade fatigue behavior. Physical testing of two titanium alloys, Ti-6Al-7Nb and Ti-15Mo, was conducted on hydraulic test frames and compared to computational simulations which were carried out for the following scenarios: cyclic excitation following plastic deformation; variation of material property definition; variation of loading location; and three modifications …


The Effect Of Static Pressure On The Inertial Cavitation Threshold And Collapse Strength, Kenneth Bryan Bader Jan 2011

The Effect Of Static Pressure On The Inertial Cavitation Threshold And Collapse Strength, Kenneth Bryan Bader

Electronic Theses and Dissertations

The amplitude of the acoustic pressure required to nucleate a gas and/or vapor bubble in a fluid, and to have that bubble undergo an inertial collapse, is termed the inertial cavitation threshold. The hydrostatic dependence of the inertial cavitation threshold was measured up to 30 MPa in ultrapure water using a high quality factor spherical resonator. The threshold increased linearly with the hydrostatic pressure and was found to be temperature dependent. The strength of the bubble collapse at the threshold was measured in terms of shock waves and light emissions. The shock amplitudes increased linearly with the hydrostatic pressure, while …


Improving Sample Collection Of Trace Particles Of Mock Explosive On Nano Coated Sensor, Daniel Woldemichael Yebo Jan 2011

Improving Sample Collection Of Trace Particles Of Mock Explosive On Nano Coated Sensor, Daniel Woldemichael Yebo

Electronic Theses and Dissertations

In protection against explosive-based terrorism, development and mass deployment of miniature sensors can play a tremendous role. In trace explosive detection, one of the challenges is bringing explosive vapor samples from the environment to the sensor element. Such collection of a selective and sufficient amount of air sample will enable the device detect the explosive at lower concentration. This can be done by adsorption of the explosive vapor on a substrate. This research implements the idea by developing a nano coated sensor on a lead zirconate titanate (PZT) substrate. The effects of varying the amount of polyethyleneimine in the nano …