Mechanical Engineering Commons^™

Energy Dissipation In A Sand Damper Under Cyclic Loading, Ehab Sabi

Civil and Environmental Engineering Theses and Dissertations

Various seismic and wind engineering designs and retrofit strategies have been in development to meet structures' proper and safe operation during earthquake and wind excitation. One such method is the addition of fluid and particle dampers, such as sand dampers, in an effort to reduce excessive and dangerous displacements of structures. The present study implements the discrete element method (DEM) to assess the performance of a pressurized sand damper (PSD) and characterize the dissipated energy under cyclic loading. The idea of a PSD is to exploit the increase in shearing resistance of sand under external pressure and the associated ability …

Experimental And Numerical Studies On Laser Hot Wire Cladding By A High-Power Direct Diode Laser, Mingpu Yao

Mechanical Engineering Research Theses and Dissertations

Laser hot wire cladding is an advanced surface modification technology. It has been extensively growing during the last decades due to its high deposition rate, good metallurgical bonding between the substrate and clad layer, low dilution ratio, and small heat-affected zone. There are many kinds of lasers widely used in the laser cladding process. The high-power direct diode laser is widely welcomed because of its high energy efficiency, high electro-optic conversion efficiency, low cost, and high reliability. A rectangular-shaped direct diode laser beam combined with hot wire feeding can achieve a lower dilution depth with a uniform fusion line compared …

Novel Locomotion Methods In Magnetic Actuation And Pipe Inspection, Adam Cox

Mechanical Engineering Research Theses and Dissertations

There is much room for improvement in tube network inspections of jet aircraft. Often, these inspections are incomplete and inconsistent. In this paper, we develop a Modular Robotic Inspection System (MoRIS) for jet aircraft tube networks and a corresponding kinematic model. MoRIS consists of a Base Station for user control and communication, and robotic Vertebrae for accessing and inspecting the network. The presented and tested design of MoRIS can travel up to 9 feet in a tube network. The Vertebrae can navigate in all orientations, including smooth vertical tubes. The design is optimized for nominal 1.5" outside diameter tubes. We …

Design Practice Book Of Mt-293 Parametric Computer-Aided Design, Raymond K.F. Lam, Md. Shahadat Hossain

Open Educational Resources

The design practice book is written for students who are enrolled in the MT-293 Parametric Computer-Aided Design course at CUNY Queensborough Community College. The book provides step-by-step instructions on creating two-dimensional models and three-dimensional models using SolidWorks software. The book also include laboratory assignments.

Mechanistic Understanding Of Phase Stability, Transformation, And Strengthening Mechanisms In Lightweight High Entropy Alloys And High Entropy Ceramics, Ganesh Walunj

ETD Archive

High-entropy alloys (HEAs) are a novel family of solid-solution alloys that have gained international interest due to their exceptional characteristics. Because of the need from the transportation and defense sectors, lightweight HEAs have attracted researcher’s curiosity as prospective advanced materials. Low-weight high entropy alloy synthesizes using arc melting with a mass ratio of AlCrFeMnTix(0.1,0.15,0.2). The synthesized HEA is comprised of a mixture of body center cubic (bcc) and ordered bcc (L21) solid solution phases. The synthesized HEAs have heat treated at 650C, 800C, and 1150C for 1hr, 4hr after solutionized at 1150C for 2 hr to understand the effect of …

Design And Performance Of A Directional Permeability Membrane, Hamidreza Bayat

Mechanical Engineering Research Theses and Dissertations

A directional permeability membrane was designed, fabricated, and tested with the goal of allowing flow in one direction and preventing flow in the opposite direction. The membranes were constructed from two porous polyimide sheets with different thicknesses and bonded with double sided tape on the perimeter to create a separation in the range of 25-75 µm. Nine holes with diameter of 0.5 and 1 mm were cut in a polyimide sheet with thickness of 125 µm and four circular holes with diameter of 0.25 mm were cut in a polyimide sheet with thickness of 25 µm. The holes were cut …

Wake Bifurcations Behind Two Circular Disks In Tandem Arrangement, Jianzhi Yang, Xiaowei Wu, Minghou Liu, Changjian Wang, Yuxin Wu, Zhihe Shen

Mechanical and Materials Engineering Faculty Publications and Presentations

The wake bifurcations behind two circular disks in tandem arrangement are investigated through numerical simulations. The separation distance between the disks, S/d, is chosen at 1, 2, 4, and 6, and the Reynolds number, Re, lies in the range of 100 Re 500. The wake dynamics are examined in terms of the flow structures as well as drag and lift coefficient characteristics. Seven main wake regimes are observed in the considered (Re, S/d) space: steady state (SS), Zig-zig (Zz) mode, standing wave mode, periodic state with reflectional symmetry breaking (RSB), periodic state with double-helical (DH) structures shedding, periodic state with …

Latam Intelligent Filter For Education (Life), Andrew Lemus, Jonathan Woo, Edison Yang, Cinthya Jauregui, Daniel Mccann-Sayles

Interdisciplinary Design Senior Theses

The LIFE system is designed to inspire primary-aged students in Latin American schools to pursue higher education in STEM related fields. We hope the students educate others in their community about the public health implications stemming from the lack of clean water and grow to bring about more lasting solutions to the water crisis. Many family’s lives are stymied by the inability to access clean drinking water, with many students ending up spending hours carrying water or spending time recovering water themselves in lieu of attending school. The LIFE team created a tabletop water filter and pump system accompanied by …

Neurogen: Eeg And Near-Infrared Light Stimulation Device, Louisa Mantilla, Samantha Perez, Michelle Wong

Interdisciplinary Design Senior Theses

Neurodegenerative diseases such as Alzheimer’s, Dementia, and Parkinson’s affect hundreds of millions of people across the nation and world each year. While medications targeting disease pathways have often resulted in debilitating side effects, neurodegenerative diseases may be targeted by common pathways that promote healing of tissues via reduced inflammation, increased perfusion, and increased energy production. Photobiomodulation (PBM) targets all of these physiological processes with non-invasive near infra-red light stimulation and for this application the treatment will be applied to the head. Transcranial PBM has been used to effectively treat neurodegenerative diseases with improved cognitive and motor control outcomes. PBM applied …

Design And Nonlinear Control Of A Haptic Glove For Virtual Palpation, Matthew Galla

Mechanical Engineering Research Theses and Dissertations

This dissertation presents the design, kinematic analysis, and nonlinear control of a Haptic Glove for medical elastographic imaging virtual palpation. Of the 13 degrees of freedom present in the index finger, middle finger, and thumb of the hand, the design fixes 4, constrains 2 and controls 6 with pneumatic air cylinder actuators, allowing uncontrolled, but measured motion in the remaining 1 degree of freedom. Nearly linear bijective transfer functions between the actuator positions and joint angles are found in closed form for all 6 actuated joints. A nonlinear, sliding-mode controller that allows each actuator to be controlled by a single …

The Effect Of Surface Gas/Liquid Entrapment On Drag Reduction, Haosen Tan

Mechanical Engineering Research Theses and Dissertations

Economic globalization has made today’s world more closely linked, where transportation (e.g. shipping, pipeline) has played an important role. Approximately over 60% (in air), 80% (underwater), and 100% (in pipeline) propulsive power is used to overcome surface drag, so reducing surface drag will have a substantial impact economically and environmentally.

To develop a surface that has lower drag, the intuitive idea is to convert no-slip boundary conditions to slip or partial slip ones. To achieve that, the most promising approach is to replace the solid-liquid boundaries completely or partially with gas-liquid or liquid-liquid boundaries, because the shear stress is much …

Resistive Pulse Sensing Of Protein Unfolding And Transport In Solid-State Nanopores, Jugal Saharia

Mechanical Engineering Research Theses and Dissertations

Solid-state nanopore sensors have attracted considerable attraction as a tool for solution-based single-molecule studies and have been successfully utilized for characterization of biomolecules such as nucleic acids, proteins, glycans, viruses, etc. Among these, characterization of proteins has been more challenging due to their charge heterogeneity and the complex energy landscape associated with different protein conformations. Presented in this thesis is the fabrication of solid-state nanopores and their application for characterizing proteins and understanding their transport through nanopores. Fabrication of nanometer-sized pores in Si_xN_y membranes was achieved using the conventional controlled dielectric breakdown method as well as a …

Mechanistic Undrestanding Of Amorphization In Iron-Based Soft Magnetic Materials, Taban Larimian

ETD Archive

Iron-based magnetic alloys possess very good magnetic and mechanical properties. Among these alloys Fe-Si-B-based alloys show outstanding saturation magnetization and coercivity which makes them great candidates for many industrial applications. Addition of certain elements to the Fe-Si-B base is proven to improve the homogeneity and fineness of microstructure as well as enhance the magnetic behavior of these alloys. In this research work, we have studied the effect of adding copper and niobium to the Fe-Si-B base alloy. Previous studies have shown that magnetic alloys show better magnetic properties when their microstructure consists of nanocrystals embedded in an amorphous matrix. In …

Ballasting System For An Autonomous Underwater Vehicle, Noura Rayes, Bahram Nassersharif, Zach Champney, Kyle Alessandro, Jason Mirandou

Senior Honors Projects

NOURA RAYES (Mechanical Engineering); Ballasting System for an Autonomous Underwater Vehicle Sponsor: Bahram Nassersharif (Mechanical Engineering)

Over the last year, our Mechanical Engineering Capstone team, Nautilus, has been working to design a ballasting system for various Autonomous Underwater Vehicles (AUVs) sponsored by Raytheon Technologies. Common AUV systems are used for a wide range of applications from environmental monitoring, oceanic exploration, to data collection. AUVs also have many technical advantages that make underwater tasks more efficient, cost-effective, and generally safer. Raytheon Technology, specifically, is looking to improve their existing ballasting mechanism for their AUVs to use for military defense. For this …

Viability And Accessibility Of Urban Heat Island And Lake Microclimate Data Over Current Tmy Weather Data For Accurate Energy Demand Predictions., Irena A. Weclawiak

ETD Archive

Building Energy Simulations (BES) are necessary for designing energy-efficient systems. Open-source simulation software developed by the Department of Energy (DOE), EnergyPlus (EP) provides Typical Meteorological Year (TMY) weather data that consists of a 15-year average. Two major concerns about this data are the inability to detect extreme conditions and limited data locations. There is a greater number of Microclimate (MC) stations that can be used for simulations, but it involves time-consuming data preparation to match the EP format. This study investigated the effects of Urban Heat Island (UHI) and the MC of Lake Erie. A comparison of the MC data …

An Evaluation And Economic Analysis Of A Water Main Geothermal System In A Residential Space, Brian L. Kohut

ETD Archive

Iron-based magnetic alloys possess very good magnetic and mechanical properties. Among these alloys Fe-Si-B-based alloys show outstanding saturation magnetization and coercivity which makes them great candidates for many industrial applications. Addition of certain elements to the Fe-Si-B base is proven to improve the homogeneity and fineness of microstructure as well as enhance the magnetic behavior of these alloys. In this research work, we have studied the effect of adding copper and niobium to the Fe-Si-B base alloy. Previous studies have shown that magnetic alloys show better magnetic properties when their microstructure consists of nanocrystals embedded in an amorphous matrix. In …

Marine Robot Sample Retrieving System, Valeriya Chulyukina, Noah Villar, Kekoa Blair, Mandeep Singh, Nathan Burke

Interdisciplinary Design Senior Theses

The exploration of our underwater ecosystems is critical. The aquatic ecosystem has a significant effect on human life, yet our understanding of the oceanic environment is severely lacking. Santa Clara University’s Robotic Systems Lab contributes to subsea exploration through its investment in remotely operated vehicle (ROV) technology. This project was done with the guidance of not only professors in the Robotics Systems Lab, but also stakeholders from the US Geological Survey scientists and researchers from the Monterey Bay Aquarium Research Institute (MBARI). Our team goal was to further advance SCU’s efforts by creating a sediment sample collection system consisting of …

Design Of A Surrogate Hypersonic Inlet For The Hifire-6 Configuration, Joseph W. Mileski

Browse all Theses and Dissertations

Shock wave-boundary layer interactions can significantly impact the operability of high-speed inlets by inducing flow separation. This flow separation is difficult to visualize in three-dimensional, inward-turning inlets because of the curved surfaces that form their internal flow paths. To remedy this challenge, a surrogate test article was created. Using the results from a previously completed Computational Fluid Dynamic (CFD) analysis of the HIFiRE-6, a surrogate inlet with a rectangular isolator section was streamline-traced, allowing for the use of schlieren imagery to capture the separation bubble. This thesis discusses the process of developing the test article. Experimental results from a planned …

Demonstration Of High-Temperature Operation Of Beta-Gallium Oxide (Β-Ga2o3) Metal-Oxide-Semiconductor Field Effect Transistors (Mosfet) With Electrostatic Model In Comsol, Nicholas Paul Sepelak

Browse all Theses and Dissertations

β-Ga2O3 is a robust semiconductor material set with a large band gap of ~4.8 eV, low intrinsic carrier concentration, and high melting point that offers a stable platform for operating electronic devices at high temperatures and extreme environments. The first half of this thesis will cover the fabrication of a fixture and packaging to test electronic components at high temperatures. Then it will highlight the characterization of β-Ga2O3 field effect transistors from room temperature (RT) up to 500 °C. The devices, fabricated with Ni/Au and Al2O3 gate metal-oxide-semiconductor (MOS), demonstrate stable operation up to 500 oC. The tested device shows …

Airflow Impact Upon Remote Laser Welding Quality, Baixuan Yang

Mechanical Engineering Research Theses and Dissertations

Laser induced plasma-plume and condensed particles attenuate the laser beam energy, resulting in keyhole instability and lacking penetration. There are various airflow devices that are currently used in both industrial and laboratory laser welding settings to suppress the detrimental effect of plasma plume and hot spatters. A systematic experimental and numerical study is presented in this dissertation that investigates different external airflow effects on the remote laser welding process used in automotive manufacturing applications.

The vertical airflow impact on the remote laser welding was first studied experimentally. The airflow velocity profiles of a coaxial vertical flow device were measured using …

Simulation Of Residual Stress Generation In Additive Manufacturing Of Complex Lattice Geometries, Katie Sue Bruggeman

Browse all Theses and Dissertations

Residual stresses developed during additive manufacturing (AM) can influence the mechanical performance of structural components in their intended applications. In this study, thermomechanical residual stress simulations of the laser powder bed fusion (LPBF) process are conducted for both simplified (plate and cube-shaped) geometries as well as five complex lattice geometries fabricated with Inconel 718. These simulations are conducted with the commercial software package Simufact Additive©, which uses a non-linear finite element analysis and layer-by-layer averaging approach in determining residual stresses. To verify the efficacy of the Simufact Additive© simulations, numerical results for the plate and cube-shape geometries are analyzed for …

Vibration Bending Fatigue Analysis Of Additively Repaired Ti-6al-4v Airfoil Blades, Lucas Jordan Smith

Browse all Theses and Dissertations

Repairing airfoil blades is necessary to extend the life of turbine engines. Directed energy deposition (DED) additive manufacturing (AM) provides the ability to add material at a specific location on an existing component. In this work, AM repairs on Ti-6Al-4V airfoil blades were analyzed to determine what effect the repair will have on the blade performance in high cycle vibration fatigue testing. Targeted sections were cut out of airfoil blades near high stress locations and repaired using DED. To understand the defects that arose with this type of repair, computed tomography imaging was used to quantify the defects from the …

Refrigeration & Pressure Circuits For The Test Apparatus On Triaxial Properties Of Polymer Foams At Arctic Temperatures, Nathaniel Ackerman

Williams Honors College, Honors Research Projects

The objective of this project is to modify the previous testing apparatus used by Dr. M. Hoo Fatt for exploration of Crushing Behavior of Polymer Foams in Sandwich Structures Operating in Arctic Regions commissioned by the Office of Naval Research and performed under the University of Akron’s Mechanical Engineering testing facilities. To do this, it is required to design a system capable of operating at a constant temperature during a testing cycle, reaching down to -60⁰C. This apparatus must also be compatible with prior equipment, facilities, persons, samples, and media.

Primarily, a copper-tube refrigeration coil design was considered to lead …

Molecular Dynamics Simulation Study Of A Polymer Droplet Transport Over An Array Of Spherical Nanoparticles, Anish Thomas

Browse all Theses and Dissertations

This study uses molecular dynamics simulations to evaluate the dynamic behavior of a partially wetting polymer droplet driven over a nanostructured interface. We consider the bead-spring model to represent a polymeric liquid that partially wets a rough surface composed of a periodic array of spherical particles. Results show that at sufficiently small values of external force, the droplet remains pinned at the particle's surface, whereas above the threshold its motion consists of alternating periods of pinning and rapid displacements between neighboring particles. The latter process involves large periodic variation of the advancing and receding contact angles due to the attachment …

Printing, Characterization, And Mechanical Testing Of Additively Manufactured Refractory Metal Alloys, Brianna M. Sexton

Browse all Theses and Dissertations

Refractory metal alloys in the tungsten molybdenum rhenium ternary system were additively manufactured using laser power bed fusion. Four ternary alloys with varying concentrations of tungsten, molybdenum, and rhenium were manufactured and manufactured again with an addition of 1 wt% hafnium carbide. Samples were heat treated to heal cracks, reduce porosity, and reduce inhomogeneity. Material microstructure was characterized before and after heat treatment using microscopy, energy dispersive x-ray spectroscopy, and electron backscatter diffraction mapping. Mechanical testing was conducted on both three-point bend specimens and compression specimens, resulting in maximum bending strengths of 677.86 MPa, and maximum compression 0.2% yield strengths …

Behavior Of 3d Printed Polymeric Triply Periodic Minimal Surface (Tpms) Cellular Structures Under Low Velocity Impact Loads, Jesse James Leiffer

Browse all Theses and Dissertations

Surface-based lattice structures such as triply periodic minimal surface (TPMS) lattices are lightweight structures that are widely being investigated for applications in automotive, aerospace, military, railway, and naval structures. Due to the recent advent of three-dimensional (3D) printing (3DP) technologies, architected cellular materials such as surface- or strut-based periodic lattice cell structures have emerged as a unique class of lightweight metamaterials. These materials possess enhanced strength to weight ratio, high stiffness, exceptional capabilities in reducing noise and vibration, insulating heat, and effective impact energy absorption. Understanding the impact behavior of such materials are important so that they can be reliably …

Cool Thermal Energy Storage: Water And Ice To Alternative Phase Change Materials, Sandra K. S. Boetcher

Publications

Cool thermal energy storage has a long history dating back to ancient times with modern developments beginning in the mid-nineteenth century where blocks of ice were cut from frozen lakes for cooling applications. Today, the prevalent mode of thermal energy storage is the utilization of ice tanks in commercial buildings for peak shaving and load shifting. In this chapter, a summary of different types of water/ice thermal energy storage systems is provided; an overview of alternative phase change materials for use in cool thermal energy storage is given; and alternative phase change material thermal energy systems, their implementation, challenges, and …

Solution-Processed Flexible Broadband Zno Photodetector Modified By Ag Nanoparticles, N. P. Klochko, K. S. Klepikova, I. V. Khrypunova, V. R. Kopach, I. I. Tyukhov, S. I. Petrushenko, S. V. Dukarov, V. M. Sukhov, M. V. Kirichenko, A. L. Khrypunova

Faculty Research, Scholarly, and Creative Activity

In this work, we present flexible broadband photodetectors (PDs) fabricated by a deposition of nanostructured zinc oxide (ZnO) films on polyimide (PI) substrates by using cheap and scalable aqueous method Successive Ionic Layer Adsorption and Reaction (SILAR). In order to increase the long-wavelength absorption of the nanostructured ZnO layer, we created its intrinsic defects, including oxygen vacancies by post-treatment at 300 °C in vacuum and thus the light-sensitive material ZnO/PI was obtained. Then we applied silver nanoparticles (Ag NPs) from a silver sol onto a nanostructured ZnO film, which were visualized using SEM in the form of spheres up to …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Viking Ax Cast by Students

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Dr. Cesmeci Awarded $1.1 mil DOE Grant
• Dr. Cesmeci Seeking to Student Researchers for DOE Grant