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Articles 151 - 180 of 1130
Full-Text Articles in Mechanical Engineering
Treadle Driven Lathe, Eleanor B. Mullard, Daniel Kronthal, Aaron Cohn, Robert Borovsky
Treadle Driven Lathe, Eleanor B. Mullard, Daniel Kronthal, Aaron Cohn, Robert Borovsky
Mechanical Engineering Design Project Class
The main objective of this senior design project was to design and build a treadle-driven, metal-cutting lathe that has the ability to cut 3/4" diameter material and produce small parts up to 3" long. The main challenge in this project was to successfully generate enough power through the treadle driven system to successfully cut metal at the proper specifications, while simultaneously meeting all of the user-needs. The entire system needed to be operated and pedaled by a single person, which put constraints on the location of the treadle relative to the lathe itself so the user could comfortably operate both …
Wind Walking Machine, Sam N. Lazechko, Taylor A. Justman, Will Nocka, Isaac Goldenthal
Wind Walking Machine, Sam N. Lazechko, Taylor A. Justman, Will Nocka, Isaac Goldenthal
Mechanical Engineering Design Project Class
Design a machine that walks using wind power.
Treadle Driven Can Opener, Chris Lowery, Stewart Martens, Dom Quaranta
Treadle Driven Can Opener, Chris Lowery, Stewart Martens, Dom Quaranta
Mechanical Engineering Design Project Class
Given the task to build a treadle driven can opener that opened a can in under 5 seconds, met cost requirements, and was robust.
Orthopedic Screwdriver Design, Tiffany M. Ewing, Ryan F. Blumenstein, Beenish Qayum
Orthopedic Screwdriver Design, Tiffany M. Ewing, Ryan F. Blumenstein, Beenish Qayum
Mechanical Engineering Design Project Class
Design an adjustable mechanical clutch screwdriver suitable for driving Orthopedic Screws into bones. The clutch would prevent over tightening and damaging bone material. The prototype design must demonstrate the function and ergonomics of the device and it must be suitable for modification into a medical device. Specify material changes and design details that would be needed for the ultimate production model.
Stress Amplification During Development Of The Tendon-To-Bone Attachment, Y. Liu, A. G. Schwartz, Victor Birman, S. Thomopoulos, G. M. Genin
Stress Amplification During Development Of The Tendon-To-Bone Attachment, Y. Liu, A. G. Schwartz, Victor Birman, S. Thomopoulos, G. M. Genin
Mechanical and Aerospace Engineering Faculty Research & Creative Works
No abstract provided.
Team Nathan Suspension, Frankie J. Wiggins, Alex D. Seitz, Justin P. Bautista
Team Nathan Suspension, Frankie J. Wiggins, Alex D. Seitz, Justin P. Bautista
Mechanical Engineering
Nathan Cooper is an 8-year old boy with Spinal Muscular Atrophy (SMA). SMA has affected Nathan’s muscle development and requires him to use the Standing Dani™ mobility device. The Standing Dani is a motorized standing wheelchair, or Wheelstand. Nathan controls and uses it to get around. Though the Standing Dani performs well for most functions, it has some distinct issues. The primary issue that this project addresses is its lack of suspension and the discomfort that Nathan feels as a result. After talking with our client, we developed several specifications generally related to geometry, safety, vehicle dynamics, and reliability. Many …
A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan, David Jonathan Gonzalez Campos
A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan, David Jonathan Gonzalez Campos
Master's Theses
A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan
David Jonathan González Campos
For many engineers that use finite element analysis or FEA, it is very important to know how to properly model and obtain accurate solutions for complicated loading conditions such as shock loading. Transient acceleration loads, such as shocks, are not as common as static loads. Analyzing these types of problems is less understood, which is the basis for this study. FEA …
Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie
Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie
Master's Theses
Hardware configurations, a control law, and a steering law are developed for a mixed hardware spacecraft that uses both control moment gyros and reaction wheels. Replacing one or more gyros in a spacecraft with a reaction wheel has potential for cost savings while still achieving much greater performance than using reaction wheels alone. Several simulated tests are run to compare the performance to a traditional all reaction wheel or all control moment gyro spacecraft, including analysis of failure modes and singular configurations. The mixed system performed similarly to all gyro systems, responding within 6% of the gyro system’s time for …
Leveraging Students’ Passion And Creativity: Ethos At The University Of Dayton, Margaret Pinnell, Malcolm Daniels, Kevin P. Hallinan, Gretchen Berkemeier
Leveraging Students’ Passion And Creativity: Ethos At The University Of Dayton, Margaret Pinnell, Malcolm Daniels, Kevin P. Hallinan, Gretchen Berkemeier
Mechanical and Aerospace Engineering Faculty Publications
The Engineers in Technical Humanitarian Opportunities of Service-learning (ETHOS) program was developed in the spring of 2001 by an interdisciplinary group (electrical, chemical, civil and mechanical) of undergraduate engineering students at the University of Dayton (UD). ETHOS was founded on the belief that engineers are more apt and capable to appropriately serve our world if they have an understanding of technology’s global linkage with values, culture, society, politics, and the economy. Since 2001, the ETHOS program at UD has grown and changed.
From conceptualization, to implementation, to maturation and national recognition, the program has addressed challenges of academic acceptance, programmatic …
Passive Phase Separation Of Microgravity Bubbly Flows Using Conduit Geometry, Ryan M. Jenson, Andrew Paul Wollman, Mark M. Weislogel, Lauren Sharp, Robert Green, Peter J. Canfield, Jörg Klatte, Michael E. Dreyer
Passive Phase Separation Of Microgravity Bubbly Flows Using Conduit Geometry, Ryan M. Jenson, Andrew Paul Wollman, Mark M. Weislogel, Lauren Sharp, Robert Green, Peter J. Canfield, Jörg Klatte, Michael E. Dreyer
Mechanical and Materials Engineering Faculty Publications and Presentations
The ability to separate liquid and gas phases in the absence of a gravitational acceleration has proven a challenge to engineers since the inception of space exploration. Due to our singular experience with terrestrial systems, artificial body forces are often imparted in multiphase fluid systems aboard spacecraft to reproduce the buoyancy effect. This approach tends to be inefficient, adding complexity, resources, and failure modes. Ever present in multiphase phenomena, the forces of surface tension can be exploited to aid passive phase separations where performance characteristics are determined solely by geometric design and system wettability. Said systems may be readily designed …
Evaluation Of Heat Recovery Options For Improved Energy Efficiency Of A Manufacturing Facility, Allison Chouinard
Evaluation Of Heat Recovery Options For Improved Energy Efficiency Of A Manufacturing Facility, Allison Chouinard
Master's Theses (2009 -)
Nationwide process heating in the manufacturing sector accounts for 7,815 trillion BTU of energy use annually; this is roughly one-third of the sector's total energy consumption [Energetics Incorporated, 2014]. The U.S. Department of Energy estimates that seventy percent of process heating is fueled by the onsite burning of fossil fuels [Energetics Incorporated, 2014]. These fuel-fired process heating applications are prime opportunities for heat recovery projects capable of saving energy and, consequently, reducing operating costs. This thesis evaluates different methods for heat recovery in the Milwaukee manufacturing facility of STRATTEC Security Corporation. As a basis for this work, the overall energy …
Application Of Variation Of Parameters To Solve Nonlinear Multimode Heat Transfer Problems, Travis J. Moore
Application Of Variation Of Parameters To Solve Nonlinear Multimode Heat Transfer Problems, Travis J. Moore
Theses and Dissertations
The objective of this work is to apply the method of variation of parameters to various direct and inverse nonlinear, multimode heat transfer problems. An overview of the general method of variation of parameters is presented and applied to a simple example problem. The method is then used to obtain solutions to three specific extended surface heat transfer problems: 1. a radiating annular fin, 2. convective and radiative exchange between the surface of a continuously moving strip and its surroundings, and 3. convection from a fin with temperature-dependent thermal conductivity and variable cross-sectional area. The results for each of these …
Characterization Of Postural Tremor In Essential Tremor Using A Seven-Degree-Of-Freedom Model, Daniel William Geiger
Characterization Of Postural Tremor In Essential Tremor Using A Seven-Degree-Of-Freedom Model, Daniel William Geiger
Theses and Dissertations
Essential Tremor (ET), a condition characterized by postural and kinetic tremor in the upper limbs, is one of the most prevalent movement disorders. While pharmaceutical and surgical treatment options exist, they are not ideal. Assistive devices have the potential to provide relief to patients but are largely unexplored for ET. Furthermore, prior characterizations of essential tremor have focused on endpoint tremor and provide insufficient detail for designing such a device. We propose and demonstrate a novel method for characterizing essential tremor in the 7 proximal degrees of freedom (DOF) of the upper limb in various postures. In addition, we provide …
Bio-Inspired Robotic Fish With Vision Based Target Tracking, Eric Anderson
Bio-Inspired Robotic Fish With Vision Based Target Tracking, Eric Anderson
Open Access Theses
The lionfish is an invasive species that out-competes and overcrowds native sh species along the eastern seaboard of the United States and down into the Caribbean. Lionfish populations are growing rapidly. Current methods of monitoring lionfish populations are costly and time intensive. A bio-inspired robotic fish was built to use as an autonomous lionfish tracking platform. Lionfish are tracked visually using an onboard processor. Five different computer vision methods for identification and tracking are proposed and discussed. These include: background subtraction, color tracking, mixture of Gaussian background subtraction, speeded up robust feature (SURF), and CamShift based tracking. Each of these …
Experimental Characterization Of Cu Free-Air Ball And Simulations Of Dielectric Fracture During Wire Bonding, Sai Sudharsanan Paranjothy
Experimental Characterization Of Cu Free-Air Ball And Simulations Of Dielectric Fracture During Wire Bonding, Sai Sudharsanan Paranjothy
Open Access Theses
Wire bonding is the process of forming electrical connection between the integrated circuit (IC) and its structural package. ICs made of material with low dielectric constant (low-k) and ultra low-k are porous in nature, and are prone to fracture induced failure during packaging process. In recent years, there is increasing interest in copper wire bond technology as an alternative to gold wire bond in microelectronic devices due to its superior electrical performance and low cost. Copper wires are also approximately 25% more conductive than Au wires aiding in better heat dissipation. At present, validated constitutive models for the strain rate …
Investigation Of Microstructural Alterations In M50 And 52100 Steel Using Nanoindentation, Kristin R. Paulson
Investigation Of Microstructural Alterations In M50 And 52100 Steel Using Nanoindentation, Kristin R. Paulson
Open Access Theses
Bearing steels are used in rolling elements and are designed to withstand heavy loads for an extended period of time. At the end of life, microstructural alterations within the material have been observed and are linked to failure. In this study, a three ball-on-rod fatigue tester was used to test M50 and 52100 steel cylindrical rods at differing loads of 4.0 GPa, 4.5 GPa, and 5.0 GPa and in lubricated and unlubricated conditions to 10 8 cycles in an attempt to produce microstructural alterations. Microstructural alterations characterized as butterflies were observed and investigated further in two M50 samples that were …
Optical Properties Of Silicon Core/Multi-Shell Nanowires Using Fdtd And Ema Methods, Tae Kon Kim
Optical Properties Of Silicon Core/Multi-Shell Nanowires Using Fdtd And Ema Methods, Tae Kon Kim
Open Access Theses
Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon core/multi-shell nanowires (SiNWs) are under active investigation for PV and solar water splitting applications because they offer novel approaches for solar to electric energy or fuel conversion leading to high efficiency devices. ^ Theoretical studies using the finite-different time-domain method have been performed to investigate the optical properties of many nanostructure arrays, however, they are computationally intensive and require periodic condition, which may not be satisfied with most fabricated samples. In the present study, effective medium approximation …
Modeling Of High Pressure Radial Piston Pumps, Pulkit Agarwal
Modeling Of High Pressure Radial Piston Pumps, Pulkit Agarwal
Open Access Theses
Agarwal, Pulkit. M.S.M.E., Purdue University, December 2014. Modeling of High Pressure Radial Piston Pumps. Major Professor: Andrea Vacca, School of Mechanical Engineering A comprehensive multi-domain simulation tool for investigating the operation of radial piston machines has been developed in the present study. The simulation tool is capable of analyzing the displacing action of the machine parts as well as the power losses occurring in the lubricating interfaces which makes it useful for supporting the design process of radial piston units. The reference machine analyzed in this study is a radial piston pump of rotating cam type design used for high …
Dropwise Condensation Dynamics In Humid Air, Julian Eduardo Castillo Chaco
Dropwise Condensation Dynamics In Humid Air, Julian Eduardo Castillo Chaco
Open Access Theses
Dropwise condensation of atmospheric water vapor is important in multiple practical engineering applications. The roles of environmental factors and surface morphology/chemistry on the condensation dynamics need to be better understood to enable efficient water-harvesting, dehumidication, and other psychrometric processes. Systems and surfaces that promote faster condensation rates and self-shedding of condensate droplets could lead to improved mass transfer rates and higher water yields in harvesting applications. The thesis presents the design and construction of an experimental facility that allows visualization of the condensation process as a function of relative humidity. Dropwise condensation experiments are performed on a vertically oriented, hydrophobic …
Effects Of Hip And Ankle Moments On Running Stability: Simulation Of A Simplified Model, Rubin C. Cholera
Effects Of Hip And Ankle Moments On Running Stability: Simulation Of A Simplified Model, Rubin C. Cholera
Open Access Theses
In human running, the ankle, knee, and hip moments are known to play different roles to influence the dynamics of locomotion. A recent study of hip moments and several hip-based legged robots have revealed that hip actuation can significantly improve the stability of locomotion, whether controlled or uncontrolled. Ankle moments are expected to also significantly affect running stability, but in a different way than hip moments. Here we seek to advance the current theory of dynamic running and associated legged robots by determining how simple open-loop ankle moments could affect running stability. We simulate a dynamical model, and compare it …
High Voltage Rear Electric Drivetrain Design For A Parallelthrough-The-Road Plug-In Hybrid Electric Vehicle, Adam Garrett Fogarty
High Voltage Rear Electric Drivetrain Design For A Parallelthrough-The-Road Plug-In Hybrid Electric Vehicle, Adam Garrett Fogarty
Open Access Theses
Purdue University was selected as one of 15 universities to participate in a three year Advanced Vehicle Technology Competition (AVTC) called EcoCar2: Plugging Into the Future. The vehicle built by the Purdue team was a Parallel-Through-The-Road Plug-in Hybrid Electric Vehicle (PTTR PHEV). The vehicle utilized a B20 diesel powertrain to power the front wheels, as well as a custom electric drivetrain to power the rear wheels. Using this vehicle during the final year of the competition, the team was successful in placing 4th overall as well as 2nd in the category of Well-To-Wheel (WTW) Greenhouse Gas Emissions. A stock 2013 …
Design And Analysis Of A Cable-Driven Test Apparatus For Flapping-Flight Research, Stephen J. Musick
Design And Analysis Of A Cable-Driven Test Apparatus For Flapping-Flight Research, Stephen J. Musick
Open Access Theses
The biology, physiology, kinematics, and aerodynamics of insect flight have been a longstanding fascination for biologists and engineers. The former three are easily obtained through the observation of the organic species. The latter though, is very difficult to study in this fashion. In many cases, aerodynamic forces and fluid-body interactions can be simulated with computational fluid dynamics; another option is to use dynamically-scaled, experimental set-ups to measure physically these values.
An archetypal, experimental set-up may include one or two scaled wings, where each wing is actuated to achieve upwards of three degrees of freedom. The three degrees of freedom correspond …
Algorithm Development And Analysis For Advanced Enginetechnologies Including Piezoelectric Fuel Injection And Variablevalve Actuation, Bradley W. Pietrzak
Algorithm Development And Analysis For Advanced Enginetechnologies Including Piezoelectric Fuel Injection And Variablevalve Actuation, Bradley W. Pietrzak
Open Access Theses
As vehicle emissions standards and fuel economy constraints become increasingly strict, the automotive industry must employ the use of advanced engine technologies to overcome these challenges. Fuel injection rate shaping and cylinder deactivation (CDA) are two such technologies, and both of them require the design and implementation of algorithms using various hardware and software tools.
Fuel injection rate shaping is one path towards cleaner and more efficient diesel engines. Piezoelectrically-actuated fuel injectors are well-suited for rate shaping operation, but are difficult to control. Control-related challenges arise primarily due to the lack of measurements available in a fuel injection system on-engine, …
Analysis Of The Impact Of Early Exhaust Valve Opening And Cylinder Deactivation On Aftertreatment Thermal Management And Efficiency For Compression Ignition Engines, Leighton Edward Roberts
Analysis Of The Impact Of Early Exhaust Valve Opening And Cylinder Deactivation On Aftertreatment Thermal Management And Efficiency For Compression Ignition Engines, Leighton Edward Roberts
Open Access Theses
In order to meet strict emissions regulations, engine manufacturers have implemented aftertreatment technologies which reduce the tailpipe emissions from diesel engines. The effectiveness of most of these systems is limited when exhaust temperatures are low (usually below 200°C to 250°C). This is a problem for extended low load operation, such as idling and during cold start. Use of variable valve actuation, including early exhaust valve opening (EEVO) and cylinder deactivation (CDA), has been proposed as a means to elevate exhaust temperatures. This thesis discusses a research effort focused on EEVO and CDA as potential enablers of exhaust gas temperature increase …
Development Of Sound Quality Metrics For Gear Rattle In Diesel Engines, Brandon Sobecki
Development Of Sound Quality Metrics For Gear Rattle In Diesel Engines, Brandon Sobecki
Open Access Theses
Sound quality is an important factor in the design of competitive diesel engines. The noise produced by specific components and mechanisms in the engine can play a significant role in determining the perceived quality of the overall noise and in turn the perceived quality of the engine. The goal of the present research is to characterize the sounds produced by the phenomenon known as gear rattle and to develop a model that can be used to assess gear rattle levels in a way that connects directly with human perception of rattle. Most previous work in this area has been focused …
Measurement Of The Responses Of Polyurethane And Confortm Foams And The Development Of A System Identification Technique To Estimate Polyurethane Foam Parameters From Experimental Impulse Responses, Vaidyanadan Sundaram
Measurement Of The Responses Of Polyurethane And Confortm Foams And The Development Of A System Identification Technique To Estimate Polyurethane Foam Parameters From Experimental Impulse Responses, Vaidyanadan Sundaram
Open Access Theses
Flexible polyurethane foam is the main cushioning element used in car seats. Optimization of an occupied seat's static and dynamic behavior requires models of foam that are accurate over a wide range of excitation and pre-compression conditions. Experiments were conducted to measure the response of foam over a wide range of excitation which include slowly varying uniaxial compression tests on a 3 inch cube foam sample, base excitation and impulse excitation test on a foam-mass system. The foam used was the same in all of the experiments, thus obtaining all the responses on the same foam sample which helps eliminate …
Waste Heat Recovery Options In A Large Gas-Turbine Combined Power Plant, Ularee Upathumchard
Waste Heat Recovery Options In A Large Gas-Turbine Combined Power Plant, Ularee Upathumchard
Open Access Theses
This study focuses on power plant heat loss and how to utilize the waste heat in energy recovery systems in order to increase the overall power plant efficiency. The case study of this research is a 700-MW natural gas combined cycle power plant, located in a suburban area of Thailand. An analysis of the heat loss of the combustion process, power generation process, lubrication system, and cooling system has been conducted to evaluate waste heat recovery options. The design of the waste heat recovery options depends to the amount of heat loss from each system and its temperature. Feasible waste …
Transport In Ultra-Thin Heat Pipes For Low Power Applications, Yashwanth Yadavalli
Transport In Ultra-Thin Heat Pipes For Low Power Applications, Yashwanth Yadavalli
Open Access Theses
Heat pipes and vapor chamber heat spreaders offer a potential solution to the increasing thermal management challenges in thin-form-factor mobile computing platforms, where efficient spreading is required to simultaneously prevent overheating of internal components and formation of hot regions on the device exterior surfaces. The operating conditions for such applications are also characterized by low input heat fluxes, which in combination with the geometric constraints, give rise to unique performance limitations that require examination. This thesis aims to characterize the steady-state and transient heat pipe performance limitations unique to such ultra-thin form factors, and characterizes the key heat transfer mechanisms …
Dissolution Rate And Mechanism Of Metals In Molten Aluminum Alloy A380, Hengyu Zhu
Dissolution Rate And Mechanism Of Metals In Molten Aluminum Alloy A380, Hengyu Zhu
Open Access Theses
Shot sleeve is a very easily worn out part in a high-pressure die-casting machine due to serious dissolution of the area underneath the pouring hole. It is because during a normal pouring process, the high temperature molten aluminum will impact and dissolve that area of the shot sleeve by complex chemical and physical process. Rotation experiment was carried out to H13 and four kinds of refractory metal samples. SEM and EDS pictures were taken in order to investigate the microstructure and the dissolution mechanism of these materials. This suggests a high strength niobium is an ideal material for that area …
Coupled Fluid-Thermal Analysis Of Low-Pressure Sublimation And Condensation With Application To Freeze-Drying, Arnab Ganguly
Coupled Fluid-Thermal Analysis Of Low-Pressure Sublimation And Condensation With Application To Freeze-Drying, Arnab Ganguly
Open Access Dissertations
Freeze-drying is a low-pressure, low-temperature condensation pumping process widely used in the manufacture of bio-pharmaceuticals for removal of solvents by sublimation. The goal of the process is to provide a stable dosage form by removing the solvent in such a way that the sensitive molecular structure of the active substance is least disturbed. The vacuum environment presents unique challenges for understanding and controlling heat and mass transfer in the process. As a result, the design of equipment and associated processes has been largely empirical, slow and inefficient.^ A comprehensive simulation framework to predict both, process and equipment performance is critical …