Mechanical Engineering Commons^™

Comparison Of Theoretical And Multi-Fidelity Optimum Aerostructural Solutions For Wing Design, Jeffrey D. Taylor, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

As contemporary aerostructural research for aircraft design trends toward high-fidelity computational methods, aerostructural solutions based on theory are often neglected or forgotten. In fact, in many modern aerostructural wing optimization studies, the elliptic lift distribution is used as a benchmark in place of theoretical aerostructural solutions with more appropriate constraints. In this paper, we review several theoretical aerostructural solutions that could be used as benchmark cases for wing design studies, and we compare them to high-fidelity solutions with similar constraints. Solutions are presented for studies with 1) constraints related to the wing integrated bending moment, 2) constraints related to the …

Mechanism Design And Analysis: Developing An Understanding Of Mechanism Motion Through Graphical Modeling, Andrew J. Hughes, Chris Merrill

Educational Leadership & Technology Faculty Publications

The intention of this article is to provide Technology and Engineering Educators with foundational knowledge of mechanism design and analysis and the ability to develop middle and high school students' mechanism knowledge during practical hands-on learning activities in the STEM classroom. Technology and Engineering Educators' implementation of mechanism design and analysis could promote students' increased depth of mechanical knowledge and ability to apply this knowledge during engineering design challenges. In this article, the authors present an introduction to four-bar mechanism design and analysis using CAD software to produce graphical representations. After designing mechanisms graphical, students should be allowed to produce …

Stabilization Of Energy Level Sets Of Underactuated Mechanical Systems Exploiting Impulsive Braking, Nilay Kant, Ranjan Mukherjee, Hassan Khalil

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Recent investigations of underactuated systems have demonstrated the benefits of control inputs that are impulsive in nature. Here we consider the problem of stabilization of energy level sets of underactuated systems exploiting impulsive braking. We consider systems with one passive degree-of-freedom (DOF) and the energy level set is a manifold where the active coordinates are fixed and the mechanical energy equals some desired value. A control strategy comprised of continuous inputs and intermittent impulsive braking inputs is presented. The generality of the approach is shown through simulation of a three-DOF Tiptoebot; the feasibility of implementation of impulsive control using standard …

Coalescence Characteristics Of Bulk Nanobubbles In Water: A Molecular Dynamics Study Coupled With Theoretical Analysis, Eric Bird, Eric Smith, Zhi Liang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Coalescence of Two Nanobubbles (NBs) in Water is a Process of Great Importance to Many Industrial Applications. in This Work, We Study the Coalescence of Two Equal-Sized Nitrogen NBs in Water using Molecular Dynamics (MD) Simulations and Continuum-Based Theoretical Analysis. We Vary the NB Diameter from 30 to 50 Nm and Study the Coalescence Characteristics Including the Expansion Speed of the Capillary Bridge between Two Coalescing NBs, the Dynamic Regime of NB Coalescence, the Diameter of Fully Merged NBs, and the Temperature Variation of NBs during the Coalescence Process. for All Cases, We Show the MD Simulation Results Can …

Thermal Vacuum Chamber Modification, Testing, And Analysis, Jared C. Lehmann

Master's Theses

This work discusses the modification and analysis of the Blue Thermal Vacuum Chamber (TVAC) located at the Space Environments Lab at California Polytechnic State University, San Luis Obispo. The modified design has a cylindrical test section and can accommodate 6U Cubesats or larger for educational or research purposes. The sizing process for the modified shroud cooling system and modular heating plates is discussed. The modified cooling system uses existing nitrogen plumbing into the chamber and control systems with a new copper shroud. The modified heating system uses modular heater plates, which utilize the existing three heater strips. The modified system …

Fourth-Order Adjoint Sensitivity And Uncertainty Analysis Of An Oecd/Nea Reactor Physics Benchmark: I. Computed Sensitivities, Ruixian Fang, Dan Gabriel Cacuci

Faculty Publications

This work extends the investigation of higher-order sensitivity and uncertainty analysis from 3rd-order to 4th-order for a polyethylene-reflected plutonium (PERP) OECD/NEA reactor physics benchmark. Specifically, by applying the 4th-order comprehensive adjoint sensitivity analysis methodology (4th-CASAM) to the PERP benchmark, this work presents the numerical results of the most important 4th-order sensitivities of the benchmark’s total leakage response with respect to the benchmark’s 180 microscopic total cross sections, which includes 180 4th-order unmixed sensitivities and 360 4th-order mixed sensitivities corresponding to the largest 3rd-order ones. The numerical results obtained in this work reveal that the number of 4th-order relative sensitivities that …

Deep Learning-Based Penetration Depth Prediction In Al/Cu Laser Welding Using Spectrometer Signal And Ccd Image, Sanghoon Kang, Minjung Kang, Yong Hoon Jang, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

In the laser welding of thin Al/Cu sheets, proper penetration depth and wide interface bead width ensure stable joint strength and low electrical conductance. In this study, we proposed deep learning models to predict the penetration depth. The inputs for the prediction models were 500 Hz-sampled low-cost charge-coupled device (CCD) camera images and 100 Hz-sampled spectral signals. The output was the penetration depth estimated from the keyhole depth measured coaxially using optical coherence tomography. A unisensor model using a CCD image and a multisensor model using a CCD image and the spectrometer signal were proposed in this study. The input …

Physical-Based Training Data Collection Approach For Data-Driven Lithium-Ion Battery State-Of-Charge Prediction, Jie Li, Will Ziehm, Jonathan W. Kimball, Robert Landers, Jonghyun Park

Electrical and Computer Engineering Faculty Research & Creative Works

Data-Driven approaches for State of Charge (SOC) prediction have been developed considerably in recent years. However, determining the appropriate training dataset is still a challenge for model development and validation due to the considerably varieties of lithium-ion batteries in terms of material, types of battery cells, and operation conditions. This work focuses on optimization of the training data set by using simple measurable data sets, which is important for the accuracy of predictions, reduction of training time, and application to online estimation. It is found that a randomly generated data set can be effectively used for the training data set, …

Testing And Characterization Of Polymer Laminates For Swelling, Absorption, And Cracking, Matthew W. Carlson

Master's Theses

A polymer laminate consisting of multiple layers of proprietary blends of Ethylene Vinyl Alcohol (EVOH) and Thermoplastic Polyurethane (TPU) and used in the construction of air bladders was evaluated for hygroscopic effects driving delamination and multiple layer fragmentation. These air bladders are observed to suffer delamination during a manufacturing process that involves immersion in an alcohol/water solution. A plausible underlying mechanism is differential swelling and absorption by the laminate constituents. Both room and elevated temperature swelling tests were carried out to find the absorption and swelling coefficients of the constituents. These coefficients served as input into a Finite Element Analysis …

Electrostatic Flocking Of Salt-Treated Microfibers And Nanofiber Yarns For Regenerative Engineering, Alec Mccarthy, Kossi Loic M. Avegnon, Phil A. Holubeck, Demi Brown, Anik Karan, Navatha Shree Sharma, Johnson V. John, Shelbie Weihs, Jazmin Ley, Jingwei Xie

Mechanical Engineering Faculty Publications

Electrostatic flocking is a textile technology that employs a Coulombic driving force to launch short fibers from a charging source towards an adhesive-covered substrate, resulting in a dense array of aligned fibers perpendicular to the substrate. However, electrostatic flocking of insulative polymeric fibers remains a challenge due to their insufficient charge accumulation. We report a facile method to flock electrostatically insulative poly(ε-caprolactone) (PCL) microfibers (MFs) and electrospun PCL nanofiber yarns (NFYs) by incorporating NaCl during pre-flock processing. Both MF and NFY were evaluated for flock functionality, mechanical properties, and biological responses. To demonstrate this platform's diverse applications, standalone flocked NFY …

Vacuum Infusion Of Composites: Durability Of Hybrid Large Area Additive Tooling For Vacuum Infusion Of Composites, Nathan Northrup, Jason Weaver, Andy R. George

Faculty Publications

The durability of a hybrid large area additively manufactured fiberglass ABS mold for vacuum infusion of composites was evaluated. The validation was done by designing and fabricating a mold for a custom test artifact and analyzing the surface geometry over the course of multiple infusions until tool failure. After printing and machining, the mold required a sealer to maintain vacuum integrity. The mold was able to produce 10 parts successfully before the sealed tool surface began to tangibly roughen, resulting in increased difficulty of demolding and a rougher surface finish. After the 14th infusion, the part required destructive force to …

Design And Development Of A Novel Soft Gripper Manipulated By A Robotic Arm, Derek Price

Symposium of Student Scholars

This study presents the design and development of a tendon-driven soft gripper manipulated by a 4 DOF robotic arm. The proposed robotic arm and the gripper explore the new areas focusing on increasing the grasping performance of the gripper as well as the workspace. The gripper is designed as a 3 finger and driven by tendons using two servo motors. The tension of the strings is adjusted using a pulley mechanism and a string. The opening and grasping of the soft gripper are accomplished by each motor. The wide opening allows the gripper to grasp wide objects. The parallel robotic …

Atomistic Simulation Of Desalination, Ian David Durr

Symposium of Student Scholars

Atomistic Simulation of Desalination

Ian Durr, Matheus Prates, and Jungkyu Park

Kennesaw State University

In this research, we investigate the desalination capacity of three-dimensional (3D) carbon nanostructures using molecular dynamics simulations. 3D carbon nanostructures proposed here will filter seawater efficiently because of their multiple layers with holes of tunable sizes. The structure is designed to be flexible, allowing mechanical deformation during daily use. The 3D carbon nanostructure will still possess high thermal conductivity, enabling easy recycle through a simple heating process. Here, we employ LAMMPS, Large-scale Atomic/MolecularMassively Parallel Simulator distributed by Sandia National Laboratories to measure salt ion flux through …

Using Comprehensive Finite Element Analysis To Simulate A Special Connection In Post-Tensioned Concrete, Joshuah Leljedal

Symposium of Student Scholars

Finite element analysis (FEA) uses differential equations to determine a computer-based solution that explains interactive behaviors within models of complex structural and mechanical systems, subjected to various loading and environmental conditions. Those systems are partitioned into finite elements consisting of a linear mesh with nodes at each end point, and FEA determines relationships, such as force-displacement, between each of the finite elements. This apportioned model allows systems to be evaluated under multiple loading scenarios. Computer-based FEA offers significant benefits that reduce cost and the time required to perform alternative analysis for complex structural systems. In this research project, a comprehensive …

The Influence Of Mechanical Properties Associated With Exercise Equipment Padding On Maximizing Performance And Minimizing Potential Soft-Tissue Injury When Performing High-Intensity Weight Lifting Exercises, Robert Hewston

Symposium of Student Scholars

The intention of this study is the measurement of mechanical properties such as resilience and compressibility associated with exercise equipment padding in order to determine the ability to minimize potential soft-tissue injuries while performing high-intensity weight lifting exercises. ASTM standards were used to test the resilience and compressibility of five different exercise equipment padding specimens. The specimens consisted of standard bench press foam, composite foam, polyethylene foam, a single yoga mat foam, and double yoga mat foam. The resilience and compressibility are tested to determine the amount of deformation each sample can experience and the level of energy returned back …

Contact Angle Measurement Using A Hele-Shaw Cell: A Proof-Of-Concept Study, Haipeng Zhang, Jacob Gottberg, Sangjin Ryu

Department of Mechanical and Materials Engineering: Faculty Publications

Contact angle is an important property to quantify the wettability of a solid surface with a liquid, which characterizes interactions of the solid-liquid pair. Generally, to measure contact angle, special instruments such as a goniometer are necessary, but they are not readily available in certain research settings. In this study, an alternative method to measure contact angle based on a Hele-Shaw cell, microscopy imaging, and image processing is suggested. In this method, a liquid drop is injected into a transparent Hele-Shaw cell, the meniscus of the drop is captured in the top or bottom view using a brightfield microscope, and …

Stable Thermally-Modulated Nanodroplet Ultrasound Contrast Agents, Anastasiia Vasiukhina, Javad Estraghi, Adib Ahmadzadegan, Craig J. Goergen, Pavlov P. Vlachos, Luis Solorio

School of Mechanical Engineering Faculty Publications

Liquid perfluorocarbon-based nanodroplets are stable enough to be used in extravascular imaging, but provide limited contrast enhancement due to their small size, incompressible core, and small acoustic impedance mismatch with biological fluids. Here we show a novel approach to overcoming this limitation by using a heating–cooling cycle, which we will refer to as thermal modulation (TM), to induce echogenicity of otherwise stable but poorly echogenic nanodroplets without triggering a transient phase shift. We apply thermal modulation to high-boiling point tetradecafluorohexane (TDFH) nanodroplets stabilized with a bovine serum albumin (BSA) shell. BSA-TDFH nanodroplets with an average diameter under 300 nanometers showed …

Flow Interaction Between Turbomachine Blade Row And Flow Resistance Medium, Tong Lin

Dissertations - ALL

This research investigates the fluid-dynamic interaction between close-coupled axial turbomachines and surrounding components, e.g., heat-exchangers, filters, or cooling fins in high-density computer servers, and its effects on turbomachine and system performance. The importance of this research is that the flow interaction effect occurs in every scenario that requires system compactness.

Firstly, a combined experimental and 3-D computational study on an off-the-shelf server cooling fan is performed, showing that the fan performance has little changed. However, the system performance can be very different since the server cooling has a large hub-to-tip radius ratio, which effectively blocks the high resistance media's (HRM) …

Molecular Interfaces And Heterogeneous Bubble Nucleation From Heated Surfaces At Nanoscale, Manish Gupta

Dissertations - ALL

Heat transfer from a solid surface to fluid occurs in numerous applications, such as boilers, refrigerators, power electronics, etc., and include various underlying phenomena of thin-film evaporation, boiling, condensation, surface wetting, and droplet evaporation. Several studies show that heat transfer can be enhanced significantly by incorporating micro and nanoscale features onto surfaces. Phase change heat transfer plays an important role in dissipating energy from hot surfaces and distributing it to bulk liquid due to high latent heat of liquids. Boiling, a phase change heat transfer phenomenon, happens when the surface is heated to a temperature above the saturation temperature of …

Multiple Uav Adaptive Navigation For Three-Dimensional Scalar Fields, Robert K. Lee, Christopher A. Kitts, Michael A. Neumann, Robert T. Mcdonald

Mechanical Engineering

Adaptive Navigation (AN) control strategies allow an agent to autonomously alter its trajectory based on realtime measurements of the environment. Compared to conventional navigation methods, these techniques can reduce required time and energy to explore scalar characteristics of unknown and dynamic regions of interest (e.g., temperature, concentration level). Multiple Uncrewed Aerial Vehicle (UAV) approaches to AN can improve performance by exploiting synchronized spatially-dispersed measurements to generate realtime information regarding the structure of the local scalar field, which is then used to inform navigation decisions. This article presents initial results of a comprehensive program to develop, verify, and experimentally implement mission-level …

Creation Of A Cip Method For The Heat Exchangers At Rolls-Royce, Melanie Howe, Austin Williams, Caroline Dempsey, Bethany Fralick

Journal of the South Carolina Academy of Science

Rolls-Royce produces various engines which must be tested prior to their distribution to ensure a high-quality product. The manufacturing plant contains four test cells where the engines can be subjected to high levels of torque and extreme temperatures. A heat exchanger is necessary in this testing system and over time, unwanted waste accumulates on the system’s plates. The team is tasked with developing and implementing a system mounted on a mobile cart which can provide data to determine whether the plates need to be cleaned. For this cleaning system to work, it must fully saturate the heat exchanger in cleaning …

The Effect Of Noise-Reducing Acoustic Panels On The Noise Levels And Overall Safety Of Infant Sleep Machines, Pranav Poola

Journal of the South Carolina Academy of Science

Infant sleep machines (ISMs) are devices used to help infants fall asleep faster and stay asleep for longer amounts of time, yet they can often be too loud for infantile ears, which could potentially be dangerous. This research aimed to minimize the risks of infant sleep machines without reducing the effectiveness of the infant sleep machines themselves through the use of acoustic panels. Based on previous studies, it was hypothesized that the acoustic panels would reduce the noise levels of the ISM to less than recommended limits of 50 dB-A. A specific corner of a designated room was prepared with …

Contact Angle Measurement Using A Hele-Shaw Cell: A Proof-Of-Concept Study, Haipeng Zhang, Jacob Gottberg, Sangjin Ryu

Department of Mechanical and Materials Engineering: Faculty Publications

Contact angle is an important property to quantify the wettability of a solid surface with a liquid, which characterizes interactions of the solid-liquid pair. Generally, to measure contact angle, special instruments such as a goniometer are necessary, but they are not readily available in certain research settings. In this study, an alternative method to measure contact angle based on a Hele-Shaw cell, microscopy imaging, and image processing is suggested. In this method, a liquid drop is injected into a transparent Hele-Shaw cell, the meniscus of the drop is captured in the top or bottom view using a brightfield microscope, and …

Design Of An Inexpensive Pvc Shock Tube For Educational Use, Brandon Edward Bergmann

Theses and Dissertations

Herein is described the design and function of a low-cost, easy-to-assemble, -operate, and -disassemble shock tube platform experiment that can generate shock waves approaching Mach 2 at maximum pressures of ~100 psig with a helium driver gas. The experiment uses several inexpensive (<$5), unamplified piezoelectric sensors attached to a multichannel oscilloscope to monitor the passage of key features of the flow (i.e., incident shock and reflected shock) through the tube, constructed from inexpensive and easy to work with schedule 40 PVC pipe and fittings. From the fixed sensor displacements along the tube and relative differences in respective transit times, the velocities of these flow features can be determined. This permits (1) comparison of experimental results to the theoretical predictions of 1-D transient gas dynamics and (2) a leaping off point for discussion and quantification of non-idealities in the flow, including the shock wave development length, shock attenuation and boundary layer growth, and interactions of the reflected shock and contact surface. Experimental accessories (future work) for study of shock focusing and steady 2-D high speed flows are also briefly discussed. Assuming both pressurized, conditioned air at ~80-100 psig and a modern multi-channel oscilloscope are available at most institutions, the total cost to construct this experiment is around $500.

Liquid Fuel Oil Produced From Plastic Based Medical Wastes By Thermal Cracking, Shahriar Bin Rasul, Uday Som, Md. Shameem Hossain, Md. Wasikur Rahman

Mechanical Engineering Faculty Publications

The present work is an effort to produce liquid fuel oil from plastic based medical wastes through thermal cracking process under oxidizing conditions. The mixed plastics from medical wastes were considered as a feedstock, shredded into small pieces and heated at 773 ± 10 K for 40 min with a heating rate of 20 K/min in a batch reactor for thermal cracking process. The feedstock was characterized by proximate and ultimate analysis along with thermogravimetric investigation. Moreover, chemical compositions of the liquid fuel oil were examined by FTIR and GC–MS spectroscopy. The properties of liquid product were also examined and …

Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen

LSU Doctoral Dissertations

Selective Laser Melting (SLM) is a laser powder bed fusion (L-PBF) based additive manufacturing (AM) method, which uses a laser beam to melt the selected areas of the metal powder bed. A customized SLM 3D printer that can handle a small quantity of metal powders was built in the lab to achieve versatile research purposes. The hardware design, electrical diagrams, and software functions are introduced in Chapter 2. Several laser surface engineering and SLM experiments were conducted using this customized machine which showed the functionality of the machine and some prospective fields that this machine can be utilized. Chapter 3 …

Using Artificial Neural Network And Fuzzy Inference System Based Prediction To Improve Failure Mode And Effects Analysis: A Case Study Of The Busbars Production, Saeed Na’Amnh, Muath Bani Salim, István Husti, Miklós Daróczi

Mechanical Engineering Faculty Publications and Presentations

Nowadays, Busbars have been extensively used in electrical vehicle industry. Therefore, improving the risk assessment for the production could help to screen the associated failure and take necessary actions to minimize the risk. In this research, a fuzzy inference system (FIS) and artificial neural network (ANN) were used to avoid the shortcomings of the classical method by creating new models for risk assessment with higher accuracy. A dataset includes 58 samples are used to create the models. Mamdani fuzzy model and ANN model were developed using MATLAB software. The results showed that the proposed models give a higher level of …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• ASME Hosts Seminar on ANSYS Simulation

Silk Fibroin Supraparticles Created By The Evaporation Of Colloidal Ouzo Droplets, Ashley Lamb, Fengjie He, Shengjie Zhai, Hui Zhao

Mechanical Engineering Faculty Research

Due to its high biocompatibility and biodegradability, supraparticles made from silk fibroin—produced from Bombyx mori (B. mori) cocoons—can find various applications in biomedical fields. The evaporation of Ouzo droplets by not requiring energy nor a surfactant is an environmentally friendly, easy, and cost-effective strategy to fabricate three-dimensional supraparticles, tackling the so-called “coffee ring effect” associated with droplet evaporation. Silk fibroins are dissolved into quaternary droplets, comprised of ultrapure water, ethanol, trans-anethole oil, and formic acid. The Ouzo droplet is able to form an oil ring that facilitates the droplet contraction to create a three-dimensional supraparticle. Using the Ouzo effect to …

Flow Characterization In Mine Ventilation Fan Blade Design Using Cfd, Anwar Endris Hassen

Journal of Sustainable Mining

In axial ventilation fans, the generation of a uniform flow velocity is desirable for better efficiency. To that end, different fan blade types have been developed to achieve better flow uniformity. This article aimed to characterize the flow distribution and its uniformity in four blade designs, namely constant chord, tapered blade, skewed blade, and tapered skewed blade, using Computational Fluid Dynamics (CFD). The study employs an iterative study where key study decisions are made as the study progresses. The study began with the selection of a blade profile for the study. A comparative study between the NACA seven-digit and four-digit …