Cryogenic Rf Test Of The First Srf Cavity Etched In An Rf Ar/Cl2 Plasma, J. Upadhyay, A. Palczewski, S. Popovic, A.-M. Valente-Feliciano, Do Im, H. L. Phillips, L. Vuskovic

Physics Faculty Publications

An apparatus and a method for etching of the inner surfaces of superconducting radio frequency (SRF) accelerator cavities are described. The apparatus is based on the reactive ion etching performed in an Ar/Cl₂ cylindrical capacitive discharge with reversed asymmetry. To test the effect of the plasma etching on the cavity rf performance, a 1497 MHz single cell SRF cavity was used. The single cell cavity was mechanically polished and buffer chemically etched and then rf tested at cryogenic temperatures to provide a baseline characterization. The cavity's inner wall was then exposed to the capacitive discharge in a mixture of …

Simulations Of Impinging Jet With A Range Of Configuration, Devansh Singh

Electronic Theses and Dissertations

Impinging jet technique is widely increasing across the globe due to its ability to produce high heat and mass transfer as compared to other traditional methods. Three cases of impinging jets related to cooling technologies for a gas turbine were investigated. The first case involves a single jet impinging on a flat plate. The second case has an array of jets impinging on a curved surface. The third case deals with simulating impinging jet in crossflow. The first case was used for validation and shows the effect of mesh and inlet boundary conditions. After careful observation, it was seen that …

Cfd Analysis Methods For Systems Driven By Natural Convection, Aaron Propst

Electronic Theses and Dissertations

Natural convection driven flows are present in many engineering applications such as HVAC, electronics cooling, and cryogenic systems. Predicting the flow behavior of such systems requires experimentation or numerical simulation through Computational Fluid Dynamics due to the complex interactions of natural convection. Recent advances in computing resources have made CFD increasingly popular for engineering analysis of fluid dynamics and heat transfer. CFD simulation has several advantages over experimentation including: 1) cost, 2) ease of changing design parameters, and 3) time required to obtain results. These advantages lead to an increased likelihood of discovering an optimal design. However, systems with complex …

Evaluating Discretization Errors With Numerical Experiments, David Dodoo-Amoo, Julio Cesar Mendez, Dehau Feng, Frederick Ferguson

Early Career Technical Journal (ECTJ)

Section 5: Materials; pp. 134-141

Lighted Ear Curette, Kaitlin Klotzle, Kelsey Ashmore, Crysta Yamamoto, Katrina Elfrink, Cynthia Stoller

Williams Honors College, Honors Research Projects

The ear canal is a sensitive and small part of the human body that is prone to accumulate cerumen or lodge foreign bodies. In order to clean the ear canal or remove foreign bodies, three hands are required: one to brace the patient's head, one to maneuver the curette that is used to clean the ear, and one to hold a light source in order to make the small, dark area visible. Therefore, a design is needed that can allow a doctor to safely clean an ear with an instrument that only requires two hands. Furthermore, the design must have …

Water Jet Cutting Head Actuator, Jacob D. Augustynovich

Williams Honors College, Honors Research Projects

In an effort to increase efficiency and productivity, WARDJet was seeking a better actuation method for the cutting head on their waterjets. Current actuation methods were, for the most part, purely mechanical, relying on compressed air, springs, and water pressure to open and close the valve to 60,000 psi of water. Increasing the speed of the on/off cycle times of the waterjet would allow for faster movements of the cutting head from one cut to the next, increasing the overall amount of products cut in a day, week, and year. This obviously points to increased sales, increased profit, and increased …

Wardjet Waterjet Cutting Head Actuator Design, Micah Steiner, Jacob D. Augustynovich, Benjamin Heckert

Williams Honors College, Honors Research Projects

In an effort to increase efficiency and productivity, WARDJet was seeking a better actuation method for the cutting head on their waterjets. Current actuation methods were, for the most part, purely mechanical, relying on compressed air, springs, and water pressure to open and close the valve to 60,000 psi of water. Increasing the speed of the on/off cycle times of the waterjet would allow for faster movements of the cutting head from one cut to the next, increasing the overall amount of products cut in a day, week, and year. This obviously points to increased sales, increased profit, and increased …

The Design And Testing Of A High Performance Formula Sae Powertrain, Ryan T. Harty

Williams Honors College, Honors Research Projects

Every year the Society of Automotive Engineers (SAE) tasks collegiate students with designing, constructing, testing, and competing with an open wheel formula style racecar. This vehicle has to meet stringent technical requirements that are provided in a rule book published by SAE. The Formula SAE (FSAE) rule book is a very comprehensive set of requirements that are centered on safety of the driver of the vehicle and the safety of the track workers. The students are required to read and understand the rulebook in order to use sound engineering practices to build not only a high performing vehicle but a …

Optimization Of Acoustic Soundboard Through Modal Analysis And Material Selection, Noah C. Nicholas, Cody Gruber, Nicholas Hartman

Williams Honors College, Honors Research Projects

The purpose of this design project was to determine if it is plausible to design an acoustic top plate assembly made of a non-traditional material which is equivalent in sound quality to that of a standard wooden guitar. Since wood must be crafted by skilled luthiers, the overall cost of producing the completed product is fairly high. To reduce the cost of a finished acoustic guitar, we proposed to alter the material to that of one that is easier to manufacture, such as plastics and composites.

Based on our research, our team chose to test both ABS plastic and carbon …

Swagelok's Hand Tube Bender, Chapin Hutama, Seth Bills, William Mcconnell, Tyler Brown

Williams Honors College, Honors Research Projects

In our project, we are assigned to develop a hand tube bender that is able to bend medium, high pressure, and standard 1/4” and 3/8” tubing. The bender also shall be capable of being used with two hands without the aid of a bench vise and have provisions for use in a bench vise for convenience. The bender shall not damage the tube during bending and induce a maximum of 8% ovality in the bent tubing. In addition, the cost of the bender shall be less than the existing hand tube bender and be resistant to rusting from ordinary use. …

Analysis And Sensitivity Study Of Zero-Dimensional Modeling Of Human Blood Circulation Network, Roussel Rahman

Browse all Theses and Dissertations

The systemic circulation has a large number of vessels; therefore, 3-D simulation of pulse-wave propagation in the entire cardiovascular system is difficult and computationally expensive. Zero-Dimensional (Zero-D) and One-Dimensional (1-D) models are simplified representations of the cardiovascular network; they can be coupled as supplements to regional 3-D models for closed-loop multi-scale studies or be simulated as self-sufficient representations of the blood-flow network. Unlike Zero-D models, 1-D models can provide linear space-wise information for the vessels. However, Zero-D models can prove to be more useful in particular cases; as flexibility in adjusting parameters facilitate in tailoring the model to specific needs. …

An Investigation On The Stress Intensity Factor Of Surface Micro-Cracks, Sirisha Divya Arli

Browse all Theses and Dissertations

The contact fatigue failure in the form of micro or macro-scale pitting is an important failure mode for rolling mechanical elements, such as bearings and gears that are widely used in the automotive, aerospace and wind turbine fields. The micro-pitting process in some cases, gradually removes the surface material through fatigue wear, altering the geometry of the contact surfaces to alleviate the contact pressure decelerating the continued pitting rate. The propagation of the micro-cracks in other cases, goes deep into the material along a shallow angle, turns parallel to the surface at a certain depth, where the maximum shear or …

One Dimensional Computer Modeling Of A Lithium-Ion Battery, Ashwin S. Borakhadikar

Browse all Theses and Dissertations

Renewable energy storage is vitally important to many applications for which batteries are the finest choice. As energy storage technology may be applied to a number of areas that differ in power and energy requirements, modeling of battery performance is required. In recent years, a lot of research has been done in this area but, the earliest model was designed by Marc Doyle, T. F. Fuller, and J. Newman in 1993. This work involves the development of a one-dimensional computer model of a lithium-ion battery which consists of three domains: the negative electrode, the separator, and the positive electrode. The …

Dynamic Modeling Of Thermal Management System With Exergy Based Optimization, Marcus J. Bracey

Browse all Theses and Dissertations

System optimization and design of aircraft is required to achieve many of the long term objectives for future aircraft platforms. To address the necessity for system optimization a vehicle-level aircraft model has been developed in a multidisciplinary modeling and simulation environment. Individual subsystem models developed exclusively in MATLAB-SimulinkTM, representing the vehicle dynamics, the propulsion, electrical power, and thermal systems, and their associated controllers, are combined to investigate the energy and thermal management issues of tactical air vehicle platforms. A thermal vehicle level tip-to-tail model allows conceptual design trade studies of various subsystems and can quantify performance gains across the aircraft. …

Nfpa Fluid Power Vehicle Challenge, Ean H. Dickerhoof

Williams Honors College, Honors Research Projects

Every year the National Fluid Power Association hosts a Fluid Powered Vehicle Challenge, this exposes students from universities all around the United States to the power and possibilities of hydraulics. This year the University of Akron’s team of engineers set out to design a bicycle that would be competitive and innovative in all aspects of the competition. In order to accomplish this, the designed bicycle must excel in three categories of competition; a sprint race, an endurance race, and an efficiency challenge.

To accomplish this task the University of Akron’s team of engineers used a lightweight bicycle frame with many …

Chocolate Bar Wrapping Machine, Austin M. Hoff, Daniel R. Trepke, Caleb B. Krichbuam

Williams Honors College, Honors Research Projects

Gilbert Chocolates has proposed to manufacture a machine to wrap chocolate bars. This machine is intended to replace two people wrapping the chocolate bars by hand, which is a time consuming method. This is especially apparent between October and January when the workers are working long hours in preparation for the Christmas rush of customers. Currently wrapping a bar takes about a minute and Gilbert Chocolates wants this time reduced down to 20-30 seconds. The budget for this project is set at $1000, and is being funded by the company. This machine needs to fit in a cubic foot of …

Instruction Pamphlet Insertion Machine, Jim Griggs, Scott Miller, Michael Kubala

Williams Honors College, Honors Research Projects

Weaver Industries in Akron, Ohio provided us with our senior design project. Weaver Industries seeks individuals with disabilities and provides them with job opportunities. One of their products is a “Kong” dog toy. As of now, the instruction pamphlet that comes with this dog toy is placed into each piece of packaging individually by hand. We are tasked with automating this process. Two years ago, a group of students worked on this project, but the reliability of their prototype was only around 60-70%. Then last year, another group of students worked on this project, but again, the reliability of their …

Lawn Mower Lift, Randall E. Schelcher

Williams Honors College, Honors Research Projects

Our team of engineers were given the task of coming up with a design project and designing the system, creating calculations, and brainstorming ideas. We set out to design a riding lawn mower lift. The purpose of this design was to assist in general maintenance like replacing blades, oil changes, etc.

To accomplish this task, our team started to brainstorm ideas and make sketches to look at all the options. We then did research and looked at different size lawn mowers and looked at the specifications. This helped our team to be able to design the size of platform needed …

Study Of Periodical Flow Heat Transfer In An Internal Combustion Engine, Xi Luo

Wayne State University Dissertations

In-cylinder heat transfer is one of the most critical physical behaviors which has a direct influence on engine out emission and thermal efficiency for IC engine. In-cylinder wall temperature has to be precisely controlled to achieve high efficiency and low emission. However, this cannot be done without knowing gas-to-wall heat flux. This study reports on the development of a technique suitable for engine in-cylinder surface temperature measurement, as the traditional method is “hard to reach.” A laser induced phosphorescence technique was used to study in-cylinder wall temperature effects on engine out unburned hydrocarbons during the engine transitional period (warm up). …

Flexural Creep Behavior Of Adhesively Bonded Metal And Composite Laminates, Hasan M. Nuwayer

Wayne State University Dissertations

Adhesively bonded structures exhibit time dependent behavior when subjected to constant load (creep). In this investigation, long-term creep behavior of adhesively bonded aluminum and carbon fiber composite beams under flexural loading was investigated. Three point bending test was selected because of its simplicity and the fact that bending stresses are quite common. In this study, two types of adhesively bonded beam specimens were tested: specimens prepared by adhesively bonding two aluminum beams and specimens prepared by adhesively bonding two unidirectional carbon fiber laminated beams. Accelerated creep tests were performed at higher temperatures up to 60 °C and deflection was measured …

Additive Manufacturing Of Al 4047 And Al 7050 Alloys Using Direct Laser Metal Deposition Process, Amrinder Singh

Wayne State University Dissertations

Additive manufacturing (AM) of metals is finding numerous applications in automotive and aerospace industry. In 21st century, aluminum is second to steel in automotive sector, because of its high strength to weight ratio. In current era, casted components of Al-Si alloy and high strength Al 7xxx series alloys are being used from low load to high load components. The primary study of this research was to achieve the defect free deposition of Al-Si and Al 7050 alloy. Al-Si alloys samples have been manufactured at lab scale using various additive manufacturing processes, but so far there is no literature available to …

Atomically Informed Nonlocal Semidiscrete Variational Peierls-Nabarro Model For Planar Core Dislocations, Guisen Liu, Xi Cheng, Jian Wang, Kaiguo Chen, Yao Shen

Department of Mechanical and Materials Engineering: Faculty Publications

Prediction of Peierls stress associated with dislocation glide is of fundamental concern in understanding and designing the plasticity and mechanical properties of crystalline materials. Here, we develop a nonlocal semi-discrete variational Peierls-Nabarro (SVPN) model by incorporating the nonlocal atomic interactions into the semi-discrete variational Peierls framework. The nonlocal kernel is simplified by limiting the nonlocal atomic interaction in the nearest neighbor region, and the nonlocal coefficient is directly computed from the dislocation core structure. Our model is capable of accurately predicting the displacement profile, and the Peierls stress, of planar-extended core dislocations in face-centered cubic structures. Our model could be …

Photoluminescence From Radiative Surface States And Excitons In Methylammonium Lead Bromide Perovskites, Dengyang Guo, Davide Bartesaghi, Haotong Wei, Eline M. Hutter, Jinsong Huang, Tom J. Savenije

Department of Mechanical and Materials Engineering: Faculty Publications

In view of its band gap of 2.2 eV and its stability, methylammonium lead bromide (MAPbBr₃) is a possible candidate to serve as a light absorber in a subcell of a multijunction solar cell. Using complementary temperature-dependent time-resolved microwave conductance (TRMC) and photoluminescence (TRPL) measurements, we demonstrate that the exciton yield increases with lower temperature at the expense of the charge carrier generation yield. The low-energy emission at around 580 nm in the cubic phase and the second broad emission peak at 622 nm in the orthorhombic phase originate from radiative recombination of charges trapped in defects with …

Helium Irradiation And Implantation Effects On The Structure Of Amorphous Silicon Oxycarbide, Qing Su, Shinsuke Inoue, Manabu Ishimaru, Jennifer A. Gigax, Tianyao Wang, Hepeng Ding, Michael J. Demkowicz, Lin Shao, Michael Nastasi

Department of Mechanical and Materials Engineering: Faculty Publications

Despite recent interest in amorphous ceramics for a variety of nuclear applications, many details of their structure before and after irradiation/implantation remain unknown. Here we investigated the short-range order of amorphous silicon oxycarbide (SiOC) alloys by using the atomic pair-distribution function (PDF) obtained from electron diffraction. The PDF results show that the structure of SiOC alloys are nearly unchanged after both irradiation up to 30 dpa and He implantation up to 113 at%. TEM characterization shows no sign of crystallization, He bubble or void formation, or segregation in all irradiated samples. Irradiation results in a decreased number of Si-O bonds …

Suspended Graphene-Based Gas Sensor With 1-Mw Energy Consumption, Jong-Hyun Kim, Qin Zhou, Jiyoung Chang

Department of Mechanical and Materials Engineering: Faculty Publications

This paper presents NH₃ sensing with ultra-low energy consumption for fast recovery and a graphene sheet based on a suspended microheater. Sensitivity and repeatability are important characteristics of functional gas sensors embedded in mobile devices. Moreover, low energy consumption is an essential requirement in flexible and stretchable mobile electronics due to their small dimension and fluctuating resistivity during mechanical behavior. In this paper, we introduce a graphene-based ultra-low power gas detection device with integration of a suspended silicon heater. Dramatic power reduction is enabled by a duty cycle while not sacrificing sensitivity. The new oscillation method of heating improves …

Vorticella: A Protozoan For Bio-Inspired Engineering, Sangjin Ryu, Rachel E. Pepper, Moeto Nagai, Danielle C. France

Department of Mechanical and Materials Engineering: Faculty Publications

In this review, we introduce Vorticella as a model biological micromachine for microscale engineering systems. Vorticella has two motile organelles: the oral cilia of the zooid and the contractile spasmoneme in the stalk. The oral cilia beat periodically, generating a water flow that translates food particles toward the animal at speeds in the order of 0.1–1 mm/s. The ciliary flow of Vorticella has been characterized by experimental measurement and theoretical modeling, and tested for flow control and mixing in microfluidic systems. The spasmoneme contracts in a few milliseconds, coiling the stalk and moving the zooid at 15–90 mm/s. Because the …

Remote Control Of The Ece Smart Kart, Sarah Dangelo

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Implementation Of A Self Leveling Controller On A Legged Rover, Rahul Rameshbabu

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

On A Time Domain Boundary Integral Equation Formulation For Acoustic Scattering By Rigid Bodies In Uniform Mean Flow, Fang Q. Hu, Michelle E. Pizzo, Douglas M. Nark

Mathematics & Statistics Faculty Publications

It has been well-known that under the assumption of a uniform mean flow, the acoustic wave propagation equation can be formulated as a boundary integral equation. However, the constant mean flow assumption, while convenient for formulating the integral equation, does not satisfy the solid wall boundary condition wherever the body surface is not aligned with the assumed uniform flow. A customary boundary condition for rigid surfaces is that the normal acoustic velocity be zero. In this paper, a careful study of the acoustic energy conservation equation is presented that shows such a boundary condition would in fact lead to source …

Design And Implementation Of An Air Multiplier Fan For Pc, George Demian

Williams Honors College, Honors Research Projects

Mechanical engineering student (B.S.) senior design project. Conception, design (SolidWorks), 3D printing & processing, testing of a scaled down air multiplier "bladeless" fan within a computer chassis as a cooling solution.