Mechanical Engineering Commons^™

On The Development Of Part-Scale Fem Modeling For Laser Powder Bed Fusion Of Aisi 316l Stainless Steel With Experimental Verification, Muhammad Arif Mahmood, Asif Ur Rehman, M. Mustafa Azeem, Abedalkader Alkhouzaam, Marwan Khraisheh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In laser powder bed fusion (LPBF), the effects of operating conditions on thermal gradients and residual stresses are the utmost challenges that require significant attention. The magnitudes of residual stress in the printed layers, as well as the distribution along the printed components, have not been well explained for LPBF parts. In this study, a 3D finite element thermo-mechanical model has been established to investigate the effect of operating conditions on thermal distribution, melt pool evolution, residual stress distribution, and part distortion. The printed AISI 316L stainless steel cubes have been characterized experimentally. The results showed a proportional correlation among …

Jme 4110: Gearbox Design, Nichols Drabb, Steven Nelson, Brian Sniezak

Washington University / UMSL Mechanical Engineering Design Project JME 4110

This team was tasked with designing or replacing an external gearbox for an electric-motor driven train car. A suitable replacement was sought for, but none was found; so, a complex set of gears, or compound gear train was designed. This gear train allowed for a smaller electric motor to drive the large rail car at appreciable speeds.

Enhancement Of Interlaminar Shear Strength Of Carbon Fiber Reinforced Polymer Composites With Freeform 3d Printing Using Magnetic Compaction & Zt-Cfrp Technologies, Mohammad Rakibul Islam

Graduate Theses and Dissertations (2019 - present)

Carbon Fiber Reinforced Polymer (CFRP) laminates often exhibit matrix-sensitive weaknesses and flaws when produced via conventional additive manufacturing (AM) techniques due to the introduction of voids and defects during the AM process. This thesis employs a new approach called Magnetic Compaction Force Assisted-Additive Manufacturing (MCFA-AM) to fabricate Carbon Nanofibers (CNF)Z-threaded CFRP (i.e., ZR-CFRP) composite laminates. This novel method utilized a magnetic force to simultaneously levitate, deposit, and compact Continuous Carbon Fiber Reinforced Polymer (C-CFRP) composites in free space and rapidly solidifies the CFRP part without any mold; and effectively reduces the voids. Previous studies have demonstrated that the incorporation of …

Effect Of Surface Fluid Entrapment In A Laminar Flat Plate Boundary Layer, Abigail Hays

Mechanical Engineering Research Theses and Dissertations

For streamlined objects in laminar flow, the drag is dominated by friction drag. To counteract this, the boundary condition of the object can be changed to introduce an apparent slip on the surface. A number of approaches have been proposed for introducing surface slip to reduce drag and viscous resistance in fluid flows. This work investigates a novel approach to providing slip via fluid entrapment in a perforated domain embedded in the surface. The fluid entrapment system uses a cavity underneath the domain to allow entrapment of fluid of the same type, or supply air to the surface perforations in …

Jme 4110: Automated Railway Decoupler, Optimized, Robert Murphy, Grace Stonner, Adam Young, Matt Stokes

Washington University / UMSL Mechanical Engineering Design Project JME 4110

Disconnecting freight cars from one another in trains that may be many thousands of feet long involves the dangerous and inefficient operation of manual decoupling. We have produced a system that enables freight cars to disconnect remotely, streamlining rail operations and boosting efficiency.

Jme 4110: Upgraded Refrigeration Door Cycling System, Keenan Bland, Kelvin Woods, Tyler Mclaughlin

Washington University / UMSL Mechanical Engineering Design Project JME 4110

This project focuses on improvements to a door cycling system. Both a fortified rope for the pulley system, ensuring extended operation, and the integration of a support track. This track is designed to bolster the clevis linked to an air piston that facilitates smooth piston rod travel without deflection. With these advancements, our door cycling system attains a new level of reliability, durability and functionality.

A Review Of Solar Hybrid Photovoltaic-Thermal (Pv-T) Collectors And Systems, Todd Otanicar

Mechanical and Biomedical Engineering Faculty Publications and Presentations

In this paper, we provide a comprehensive overview of the state-of-the-art in hybrid PV-T collectors and the wider systems within which they can be implemented, and assess the worldwide energy and carbon mitigation potential of these systems. We cover both experimental and computational studies, identify opportunities for performance enhancement, pathways for collector innovation, and implications of their wider deployment at the solar-generation system level. First, we classify and review the main types of PV-T collectors, including air-based, liquid-based, dual air–water, heat-pipe, building integrated and concentrated PV-T collectors. This is followed by a presentation of performance enhancement opportunities and pathways for …

The Plastics Collection Reference Packet, Special Collections Research Center

Special Collections Research Center

This reference packet is an informational tool to support further research into the history of plastics—whether interested in companies, individuals within the plastics industry's history, historical plastics materials, essays, and more. All content featured within this packet was previously published on the former plastics.syr.edu website as part of a Syracuse University Libraries and Special Collections Research Center (SCRC) partnership established in 2007 with the Plastics Pioneers Association (PPA)—an association of plastics industry professionals interested in preserving the plastics industry's past.

Kinetic Particle Simulations Of Plasma Charging At Lunar Craters Under Severe Conditions, David Lund, Xiaoming He, Daoru Frank Han

Mathematics and Statistics Faculty Research & Creative Works

This paper presents fully kinetic particle simulations of plasma charging at lunar craters with the presence of lunar lander modules using the recently developed Parallel Immersed-Finite-Element Particle-in-Cell (PIFE-PIC) code. The computation model explicitly includes the lunar regolith layer on top of the lunar bedrock, taking into account the regolith layer thickness and permittivity as well as the lunar lander module in the simulation domain, resolving a nontrivial surface terrain or lunar lander configuration. Simulations were carried out to study the lunar surface and lunar lander module charging near craters at the lunar terminator region under mean and severe plasma environments. …

Modeling, Control, And Hardware Development Of A Thrust-Vector Coaxial Uav, Andrew North

Doctoral Dissertations and Master's Theses

This thesis introduces a unique thrust vector coaxial unmanned aerial vehicle (UAV) configuration and presents a comprehensive investigation encompassing dynamics modeling, hardware design, and controller development. Using the Newton-Euler method, a dynamic model for the UAV is derived to gain in-depth insights into its fundamental flight characteristics. A simple thrust model is formulated and modified by comparing it with data obtained from vehicle testing. The feasibility of manufacturing such a vehicle is assessed through the development of a hardware prototype. Finally, a linear state feedback controller is designed and evaluated using the non-linear dynamics model. The results demonstrate successful validation …

Aeroponic System Optimization For Butterhead Lettuce Growth And Future Sustainability Using Flow Blurring Atomization, Taylor J. Johnson

Doctoral Dissertations and Master's Theses

The global population has grown by 6 billion people over the last century and is trending toward 9.7 billion people by the year 2050. Agriculture accounts for 70% of global fresh water usage. Technology must be developed to accommodate the increase of food production demanded by the growing global population and the subsequent increase in water usage. Aeroponic technology is a water-efficient vertical farming technology that can reduce water usage by 90% by suspending plant roots in air within a controlled chamber and supplying atomized droplets of a water-nutrient solution directly to the roots.

This study simultaneously tests six droplet …

Tribological Behavior Of Polydopamine/Polytetrafluoroethylene Coating On Laser Textured Stainless Steel With Hilbert Curves, Firuze Soltani-Kordshuli, Nathaniel Harris, Min Zou

Mechanical Engineering Faculty Publications and Presentations

Shallow Hilbert curve patterns with easily programmable texture density were selected for laser texturing of stainless steel substrates. Two different texture path segment lengths (12 and 24 mu m) and four different laser power percentages (5%, 10%, 15%, and 20%) were investigated. The textured and smooth substrates were coated with thin polydopamine/polytetrafluoroethylene (PDA/PTFE) coatings for tribological property assessment. The effects of texture density (texture area coverage) and laser power on the durability and friction of the coated surfaces were studied. Laser texturing the substrates improved the coating durability up to 25 times, reduced the friction coefficient, and prevented coating global …

Development Of Atomistic Machine Learning Approaches For Thermal Properties Of Multi-Component Solids And Liquids, Alejandro David Rodriguez

Theses and Dissertations

Currently, heat transfer in many industries is the limiting factor for innovation, especially in the energy sector. For example, maximizing thermal conductivity of ceramic coatings in power plant devices improves the overall electrical to thermal energy ratio, whereas minimizing thermal conductivity is required for desirable heat-to-electricity conversion in thermoelectric devices. As such, rapid discovery of new materials with extreme thermal conductivity values is quintessential for the near-future deployment of current and developing energy applications.

The vibrational properties of crystalline materials are essential for their ability to conduct heat. Fundamentally, the restorative atomic forces of displaced atoms are sufficient to represent …

Pectus Carinatum Patient Brace Data, Brandon Scott Sargent, Katie Varela, Dennis Eggett, Emily Mckenna, Christina Bates, Rebeccah Brown, Victor Garcia, Larry Howell

ScholarsArchive Data

Data for the journal article "Modeling of the chest wall response to prolonged bracing in pectus carinatum" submitted to PLOS One in 2023 by Sargent et al. The data is a recording of prescribed brace pressures, patient reported hours of wear, and clinician recorded pressure to correct through the treatment process. The data file was compiled via Microsoft Excel as part of the Microsoft 365 Office Suite. The top row of each sheet within the file is the header line with the data in all subsequent rows. The journal article contains an in-depth definition of the variables used in the …

Tio2 Coating Methods On Sb2o3 And Their Use As Anode Material In Lithium-Ion Batteries, Kithzia Czarina Gomez

Theses and Dissertations

The following thesis is concentrated on the development of TiO2Sb2O3 composite material through the hydrolysis of TiCl4 to be applied as anode material for lithium-ion batteries. Antimony (Sb) has been a material of interest due to its high capacity and good chemical properties. The TiO2 accommodated the harsh volume expansion that Sb encounters during the alloying process while still preserving the high capacity offered by Sb. Its electrochemical performance exhibited a stabilized capacity of 523 mAhg-1 after reaching 40 cycles with a capacity loss of 2.4% till reaching 100 cycles. High reversible capacity characteristics were present with an initial capacity …

Construction Of A Real-Time Forecast Model With Deep Learning Techniques For Coastal Engineering & Processes: Nested In Basin Scale Suite Of Models, Md Ahsan Habib

Theses and Dissertations

The study aims to develop a robust and adaptable real-time forecasting system for coastal and estuarine regions, considering the challenges of limited or unavailable forecast data. To address the challenge of data unavailability, this study proposes the application of a deep learning model (DLM). This research involves the development of a high-resolution numerical model nested within global models. Calibration and validation are performed by comparing the model with observed data. The study explores the effects of various parameters, such as vertical resolution, wind variability, and bottom roughness, on model performance. It finds that the 10-layer model improves vertical stratification and …

Image Segmentation With Human-In-The-Loop In Automated De-Caking Process For Powder Bed Additive Manufacturing, Vincent Opare Addo Asare-Manu

Theses and Dissertations

Additive manufacturing (AM) becomes a critical technology that increases the speed and flexibility of production and reduces the lead time for high-mix, low-volume manufacturing. One of the major bottlenecks in further increasing its productivity lies around its post-processing procedures. This work focuses on tackling a critical and inevitable step in powder-bed additive manufacturing processes, i.e., powder cleaning or de-caking. Pressing concerns can be raised with human involvement when performing this task manually. Therefore, a robot-driven automatic powder cleaning system could be an alternative to reducing time consumption and increasing safety for AM operators. However, since the color and surface texture …

Effect Of Nanoparticle Loading And Magnetic Field Application On The Thermodynamic, Optical, And Rheological Behavior Of Thermoresponsive Polymer Solutions, Christopher A. P. Neal, Grace V. Kresge, Michelle C. Quan, Valeria León, Nondumiso O. Chibambo, Michelle A. Calabrese

Mechanical Engineering Faculty Publications

Although processing via external stimuli is a promising technique to tune the structure and properties of polymeric materials, the impact of magnetic fields on phase transitions in thermoresponsive polymer solutions is not well-understood. As nanoparticle (NP) addition is also known to impact these thermodynamic and optical properties, synergistic effects from combining magnetic fields with NP incorporation provide a novel route for tuning material properties. Here, the thermodynamic, optical, and rheological properties of aqueous poly(N-isopropyl acrylamide) (PNIPAM) solutions are examined in the presence of hydrophilic silica NPs and magnetic fields, individually and jointly, via Fourier-transform infrared spectroscopy (FTIR), magneto-turbidimetry, …

A Direct Fiber Approach To Model Sclera Collagen Architecture And Biomechanics, Fengting Ji, Manik Bansal, Bingrui Wang, Yi Hua, Mohammad R. Islam, Felix Matuschke, Markus Axer, Ian A. Sigal

Mechanical Engineering Faculty Publications

Sclera collagen fiber microstructure and mechanical behavior are central to eye physiology and pathology. They are also complex, and are therefore often studied using modeling. Most models of sclera, however, have been built within a conventional continuum framework. In this framework, collagen fibers are incorporated as statistical distributions of fiber characteristics such as the orientation of a family of fibers. The conventional continuum approach, while proven successful for describing the macroscale behavior of the sclera, does not account for the sclera fibers are long, interwoven and interact with one another. Hence, by not considering these potentially crucial characteristics, …

Automated Fiber Placement Through Thickness Defect Stacking Optimization, Noah Christopher Swingle

Theses and Dissertations

In its 2022 commercial market outlook, Boeing forecasted an 80% increase in the global fleet through 2041 compared to 2019 pre-pandemic levels. This sharp rise in demand will drive pressure onto airframe manufacturers to ramp up production and find more efficient ways to design and manufacture airplanes. Complicating this challenge is the industry’s recent transformation from traditional metal-based airframes towards hybrid composite-metal aircraft. While composites have been used in aviation for decades, aircraft manufacturers are still struggling to design and manufacture quality parts at a high rate. Automated Fiber Placement (AFP) is one of the main manufacturing techniques used to …

Gpu-Enabled Genetic Algorithm Optimization And Path Planning Of Robotic Arm For Minimizing Energy Consumption, Yichuan Cao

Theses and Dissertations

The robotic arm represents a complicated mechanical system and advanced engineering principles in robotics, enabling precise and efficient manipulation and interaction with objects in a variety of applications, such as manufacturing, healthcare, space exploration, and other industries. In most cases, energy consumption of robotic tools has been given little consideration due to their perceived insignificance compared to the benefits they offer. However, the increasing capacity demands of factories and the expanding use of robotic arms necessitate careful evaluation and reduction of energy consumption. In this regard, given a task configuration, adjusting the arm's movement path emerges as one of the …

Liquid Cooling System For A High Power, Medium Frequency, And Medium Voltage Isolated Power Converter, Hooman Taghavi

Theses and Dissertations

Controlling and transforming electrical power from one form into another is the Primary function of the power electronics systems that are employed today. These systems have a wide variety of applications and are utilized in things like industrial automation, electric cars, consumer electronics, and renewable energy systems, among other things. The functioning of power electronics systems results in the production of a substantial quantity of heat, despite the fact that these systems are very dependable and efficient. This heat must be dispersed to preserve system performance and avoid component damage. By ensuring that the working temperature of the components stays …

Jme 4110: Door Cycling Station, Briana Kagy, Alexander Clark, William Todd, Seth Flamm

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The objective of this project was to design and build a door cycling station to be used for fatigue testing commercial refrigerator doors, including the door gaskets, hinges, and handles. The system must be low maintenance and reliable for at least two million cycles, and it must fit within the provided budget. The design concept includes a rodless pneumatic cylinder and a system of wear-resistant ropes, eyebolts, and pulleys.

Cu2o Heterojunction Solar Cell With Photovoltaic Properties Enhanced By A Ti Buffer Layer, Binghao Wang, Zhiqiang Chen, Feng Zhao

Center for Electron Microscopy and Nanofabrication Publications and Presentations

In this study, semiconductor oxide cuprite (Cu2O) and indium tin oxide (ITO) heterojunction solar cells with and without a 10 nm thick titanium (Ti) thin film as the buffer layer were fabricated and characterized for comparison. The Cu2O film was formed by low-cost electrodeposition, and Ti and ITO layers were deposited on a glass substrate by sputtering. The interfacial microstructures, surface topology, and electrical and photovoltaic properties of both solar cells were investigated. The test results showed that the Ti buffer layer changed the surface morphology, resistivity, and contact potential of the electrodeposited Cu2O film. With these changes, the photovoltaic …

An Empirical Investigation Of The Behavior And Cognition Of Engineering Designers While Describing Domains Of Design Problems, John Kochenberger

Theses and Dissertations

This thesis presents a protocol study that examines the behavioral and cognitive patterns in human designers when they describe a problem domain of engineering interest through constructing concept maps. Understanding various design problem domains usually comes in design projects before the start of the formal design process and is crucial for discovering the pain points of given scenarios and identifying opportunities for creating value to improve them. Thus, this activity relies on the entrepreneurial aspects of engineering design that leads to identifying the right design problem to solve. While concept maps have been used to examine various research questions in …

Algorithms For The Generalized Inverse Solution And Direct Solution: Using An Algebra Computer-Based System To Obtain Meridian Arc Length, Wei-Kuo Tseng, King-Cheng Tsai, Chian Liou, Jiunn-Liang Guo, Yi-Jia Sun

Journal of Marine Science and Technology–Taiwan

In this study, the idea employed in the article of [1] to treat the problem of the arc-length of meridian is applied to the arc-length determined by the third flattening (n) instead of the eccentricity (e) of an Earth-reference ellipsoid . With WGS 84 ellipsoid datum used in modern navigation, the meridian arc-length is a crucial factor for map projections and geodetic and distance calculations such as Mercator charts, the universal transverse Mercator, great circle (ellipse), rhumb line, and geodesic. Because navigation software lacks officially standardized calculation methods, these “black box solutions” used in navigational systems are unknown. Therefore members …

Three-Dimensional Higher-Order Compressive Sensing For Raypath Separation In An Acoustic Waveguide, Fengyan Zhong

Journal of Marine Science and Technology–Taiwan

In an acoustic waveguide, the separation of multiple raypaths, especially close raypaths, is a challenging task in the presence of colored noise due to interference in the acoustic eld. In this paper, a three-dimensional higher-order compressive sensing method for raypath separation is proposed. The method is applied on an array-to-array experimental conguration where both emitter and reception arrays are used. With the array-to-array conguration, the raypaths are characterized by three parameters including arrival direction, departure direction, and arrival time. Furthermore, the performance of the proposed algorithm is illustrated by simulations and experiments. The numerical results based on simulation illustrate that …

Projection Of Sea Surface Temperature Based On Empirical Mode Decomposition And Its Application In Typhoon Number Forecast, Wen-Cheng Huang, Jung-Chen Lee

Journal of Marine Science and Technology–Taiwan

The primary objective of this paper is to demonstrate the applicability of empirical mode decomposition (EMD) in projecting non-stationary daily sea surface temperature (SST) series, and the other is to apply the projected series of SST to estimate the number of typhoons. The study focuses on an area ranging from 5°N~25°N and 110°E~170°E, collecting daily sea temperature data and typhoons records within this region. The findings conclusively indicate that the EMD-based data generation method proposed in this paper can effectively addresses the limitations of previous hydrological models in generating non-stationary series, signifying a significant advancement in hydrological time series modeling …

Nitric Oxide: Physiological Functions, Delivery, And Biomedical Applications, Syed Muntazir Andrabi, Navatha Shree Sharma, Anik Karan, S. M. Shatil Shahriar, Brent Cordon, Bing Ma, Jingwei Xie

Department of Mechanical and Materials Engineering: Faculty Publications

Nitric oxide (NO) is a gaseous molecule that has a central role in signaling pathways involved in numerous physiological processes (e.g., vasodilation, neurotransmission, inflammation, apoptosis, and tumor growth). Due to its gaseous form, NO has a short half-life, and its physiology role is concentration dependent, often restricting its function to a target site. Providing NO from an external source is beneficial in promoting cellular functions and treatment of different pathological conditions. Hence, the multifaceted role of NO in physiology and pathology has garnered massive interest in developing strategies to deliver exogenous NO for the treatment of various regenerative and biomedical …

Smart Grid In Tanzania: Research Opportunities, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

reinvigorated its power generation capacity significantly to ensure smooth execution of its industrialization agenda and cope with the fourth industrial revolution. To ensure reliable availability of power to sustain its growing economy, Tanzania embarked on a deliberated measure to forge an energy mix. This deliberate measure encompasses the use of renewable energy technologies such as wind, solar, biomass, wastes, and micro hydro; natural gas; and other energy sources which are locally available including coal and geothermal. To effectively and efficiently manage such a growing power system and make electricity accessible to all for higher levels of industrial investment and services, …