Boron Nitride Nanotubes: Force Field Parameterization, Epoxy Interactions, And Comparison With Carbon Nanotubes For High-Performance Composite Materials,
2023
Michigan Technological University
Boron Nitride Nanotubes: Force Field Parameterization, Epoxy Interactions, And Comparison With Carbon Nanotubes For High-Performance Composite Materials, Swapnil S. Bamane, Michael B. Jakubinek, Krishan Kanhaiya, Behnam Ashrafi, Hendrik Heinz, Gregory Odegard
Michigan Tech Publications
Boron nitride nanotubes (BNNTs) are a very promising reinforcement for future high-performance composites because of their excellent thermo-mechanical properties. To take full advantage of BNNTs in composite materials, it is necessary to have a comprehensive understanding of the wetting characteristics of various high-performance resins. Molecular dynamics (MD) simulations provide an accurate and efficient approach to establish the contact angle values of engineering polymers on reinforcement surfaces, which offers a measure for the interaction between the polymer and reinforcement. In this research, MD simulations and experiments are used to determine the wettability of various epoxy systems on BNNT surfaces. The reactive …
Automatic Dispersion, Defect, Curing, And Thermal Characteristics Determination Of Polymer Composites Using Micro-Scale Infrared Thermography And Machine Learning Algorithm,
2023
The University of Texas Rio Grande Valley
Automatic Dispersion, Defect, Curing, And Thermal Characteristics Determination Of Polymer Composites Using Micro-Scale Infrared Thermography And Machine Learning Algorithm, Md Ashiqur Rahman, Mirza Masfiqur Rahman, Ali Ashraf
Mechanical Engineering Faculty Publications and Presentations
Infrared thermography is a non-destructive technique that can be exploited in many fields including polymer composite investigation. Based on emissivity and thermal diffusivity variation; components, defects, and curing state of the composite can be identified. However, manual processing of thermal images that may contain significant artifacts, is prone to erroneous component and property determination. In this study, thermal images of different graphite/graphene-based polymer composites fabricated by hand, planetary, and batch mixing techniques were analyzed through an automatic machine learning model. Filler size, shape, and location can be identified in polymer composites and thus, the dispersion of different samples was quantified …
Biogas Combustion Characteristics In A Concentric Flow Slot Burner: Effects Of Co2 Concentration On Stability And Flame Structure,
2023
American University in Cairo
Biogas Combustion Characteristics In A Concentric Flow Slot Burner: Effects Of Co2 Concentration On Stability And Flame Structure, Maged Kiriakos
Theses and Dissertations
Biogas combustion is affected by the concentration of carbon dioxide. The successful applications of Biogas as a sustainable renewable alternative fuel produced from waste depend on its combustion stability, heat release, and pollution level. The aim of the current study is to apply new combustion technology and study the stability and combustion characteristics of natural gas with different percentages of carbon dioxide from 0 to 40% simulating biogas fuel. The stability characteristics and the temperature profiles of turbulent planar flames at different levels mixture inhomogeneity are investigated and presented in this work. The flames are created in a newly developed …
Simulation Of Natural Tornado Genesis And Evolution From An Initial Instability Profile,
2023
Missouri University of Science and Technology
Simulation Of Natural Tornado Genesis And Evolution From An Initial Instability Profile, Kakkattukuzhy M. Issac
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A likely mechanism for the little-understood tornado genesis is proposed and its numerical implementation is presented. The Burgers-Rott vortex with its axis in the vertical direction is introduced as an instability mechanism, and the flow field then evolves under the influence of the atmospheric pressure, temperature and density variations with altitude. Buoyancy effects are implemented using the Boussinesq model. Results are presented and discussed for a set of conditions including mesh type and size, different turbulence models, and a few different boundary conditions. Post-processed results of the transient simulations including animations contain a wealth of information to help analyze tornado …
Changes In The Mechanical Performance Of An Ortho-Planar Spring After Aging Tests,
2023
Pontifical Catholic University of Rio de Janeiro (PUC-Rio)
Changes In The Mechanical Performance Of An Ortho-Planar Spring After Aging Tests, Lucas F. L. Santos, Larry L. Howell, Jose J. R. D’Almeida
Faculty Publications
This paper analyzed an ortho-planar spring (OPS) compliant mechanism and evaluated its mechanical performance after hygrothermal and ultraviolet radiation aging tests. The aging analysis performed here addresses the performance of compliant mechanisms after aging processes which can help inform the design of future compliant mechanisms. ASTM D638 tensile test type I samples were also submitted to aging to serve as a comparison for OPS samples. The samples were submitted to three different kinds of aging conditions, namely water immersion, oil immersion, and ultraviolet radiation. In conclusion, tensile samples showed significant statistical changes in Young's modulus and elongation at break, whereas …
Estimation Of The Response, Power Spectra, And Whirling Patterns Generated From Mud Circulating Along The Annulus During Drilling Procedures: An Alternative Mathematical Representation Via Finite Element Modelling,
2023
The University of Texas Rio Grande Valley
Estimation Of The Response, Power Spectra, And Whirling Patterns Generated From Mud Circulating Along The Annulus During Drilling Procedures: An Alternative Mathematical Representation Via Finite Element Modelling, Eleazar Marquez
Mechanical Engineering Faculty Publications and Presentations
In this study, an alternative mathematical representation of a drill-string is proposed to provide an alternative assessment on BHA dynamic alterations. Lateral vibrations remain the focal point of drill-string breakdowns given their high frequency characterization and ability to deviate perforation trajectories from the subsurface target. In this paper, the proposed model consists of an anisotropic rotor subjected to distinct RPMs, an axial force, and a bidirectional harmonic excitation with specified amplitude and assorted duration to simulate annulus motion generated from the mud fluid. In this regard, Euler-Bernoulli beam theory was adopted to establish a complete MDOF mathematical expression and thus …
Study Of The Graphene Energy Absorbing Layer And The Viscosity Of Sodium Alginate In Laser-Induced- Forward-Transfer (Lift) Bioprinting,
2023
The University of Texas Rio Grande Valley
Study Of The Graphene Energy Absorbing Layer And The Viscosity Of Sodium Alginate In Laser-Induced- Forward-Transfer (Lift) Bioprinting, Shuqi Zhou, Jianzhi Li, Ben Xu
Manufacturing & Industrial Engineering Faculty Publications and Presentations
Laser induced forward transfer (LIFT) bioprinting has been viewed as a new and actively developed three-dimensional bioprinting technology due to its high accuracy and good cell viability. The printing quality is highly dependent on the jet formation and its stability in the LIFT bioprinting process. The objective of this study is to investigate the effect of a graphene Energy Absorbing Layer (EAL) and alginate hydrogel (SA) (w.t. 1% and 2%) viscosity on jet generation in the LIFT bioprinting process. Since SA exhibits a shear-thinning behavior, it is a non-Newtonian fluid. The effect of EAL thickness and SA’s viscosity were addressed …
A Probabilistic Analysis In Vibration-Assisted Drilling To Measure Dynamic Behavior During Drilling And Understand Risk Factors,
2023
The University of Texas Rio Grande Valley
A Probabilistic Analysis In Vibration-Assisted Drilling To Measure Dynamic Behavior During Drilling And Understand Risk Factors, Eleazar Marquez, Samuel Garcia
Mechanical Engineering Faculty Publications and Presentations
In this paper, a mathematical representation is proposed to further understand the dynamic behavior and risk factors associated with vibration-assisted drilling (VAD) technology. The proposed Timoshenko beam model, which characterizes VAD technology, consists of two passive, counter-rotating coaxial rotors operating simultaneously, subjected to a stochastic excitation. In this regard, a finite element technique was incorporated to determine the physical parameters of the governing equation of motion, where the shear and rotary effects, as well as the gyroscopic couples generated perpendicular to the axis of rotation, were accounted for. Further, the relative velocity between the coaxial rotors was accounted in the …
Quadcopter Control Using Single Network Adaptive Critics,
2023
The University of Texas Rio Grande Valley
Quadcopter Control Using Single Network Adaptive Critics, Alberto Velazquez, Lei Xu, Tohid Sardarmehni
Mechanical Engineering Faculty Publications and Presentations
In this paper, optimal tracking control is found for an inputaffine nonlinear quadcopter using Single Network Adaptive Critics (SNAC). The quadcopter dynamics consists of twelve states and four controls. The states are defined using two related reference frames: the earth frame, which describes the position and angles, and the body frame, which describes the linear and angular velocities. The quadcopter has six outputs and four controls, so it is an underactuated nonlinear system. The optimal control for the system is derived by solving a discrete-time recursive Hamilton-Jacobi-Bellman equation using a linear in-parameter neural network. The neural network is trained to …
Development Of An Improved Mathematical Representation Which Captures The Nonlinear Dynamic Behavior Of A Drill-String Assembly,
2023
The University of Texas Rio Grande Valley
Development Of An Improved Mathematical Representation Which Captures The Nonlinear Dynamic Behavior Of A Drill-String Assembly, Eleazar Marquez
Mechanical Engineering Faculty Publications and Presentations
In this study, an improved mathematical representation of a drill-string assembly is developed to provide an alternative assessment on vibration irregularities proliferating downhole due to bit-rock interference. Lateral vibrations receive particular attention due to their high frequency content which alter the dynamic response of the drill-string, instigate casing damage, and impede optimal penetration rates. The response of the drill-string is captured by synthesizing compatible stationary bit excitations, via an auto-regressive digital filter, and implementing Monte Carlo simulation, while the power spectral density function is approximated to elucidate the dynamic characteristics during drilling. Formulating adequate physical parameters for the equation of …
Session 11: Can Machine Learning Predict Particle Deposition At Specific Intranasal Regions Based On Computational Fluid Dynamics Inputs/Outputs And Nasal Geometry Measurements?,
2023
South Dakota State University
Session 11: Can Machine Learning Predict Particle Deposition At Specific Intranasal Regions Based On Computational Fluid Dynamics Inputs/Outputs And Nasal Geometry Measurements?, Mohammad Mehedi Hasan Akash, Zachary Silfen, Diane Joseph-Mccarthy, Arijit Chakravarty, Saikat Basu
SDSU Data Science Symposium
Along with machine learning modeling, numerical simulations of respiratory airflow and particle transport can be used to improve targeted deposition at the upper respiratory infection site of numerous airborne diseases. Given the need for more patient data from varied demographics, we propose a machine learning-enabled protocol for determining optimal formulation design parameters that may match nasal spray device settings for successful drug delivery. We measured 11 anatomical parameters (including nasopharyngeal volume, nostril heights, and mid-nasal cavity volume) for 10 CT-based nasal geometries representative of the population for this aim. We also ran 160 computational fluid dynamics simulations of drug delivery …
Session 2: The Effect Of Boom Leveling On Spray Dispersion,
2023
South Dakota State University
Session 2: The Effect Of Boom Leveling On Spray Dispersion, Travis A. Burgers, Miguel Bustamante, Juan F. Vivanco
SDSU Data Science Symposium
Self-propelled sprayers are commonly used in agriculture to disperse agrichemicals. These sprayers commonly have two boom wings with dozens of nozzles that disperse the chemicals. Automatic boom height systems reduce the variability of agricultural sprayer boom height, which is important to reduce uneven spray dispersion if the boom is not at the target height.
A computational model was created to simulate the spray dispersion under the following conditions: a) one stationary nozzle based on the measured spray pattern from one nozzle, b) one stationary model due to an angled boom, c) superposition of multiple stationary nozzles due an angled boom, …
Symmetric Equations For Evaluating Maximum Torsion Stress Of Rectangular Beams In Compliant Mechanisms,
2023
Xi’an Jiaotong University
Symmetric Equations For Evaluating Maximum Torsion Stress Of Rectangular Beams In Compliant Mechanisms, Guimin Chen, Larry L. Howell
Faculty Publications
There are several design equations available for calculating the torsional compliance and the maximum torsion stress of a rectangular cross-section beam, but most depend on the relative magnitude of the two dimensions of the cross-section (i.e.,the thickness and the width). After reviewing the available equations, two thickness-to-width ratio independent equations that are symmetric with respect to the two dimensions are obtained for evaluating the maximum torsion stress
of rectangular cross-section beams. Based on the resulting equations, outside lamina emergent torsional joints are analyzed and some useful design insights are obtained. These equations, together with the previous work on symmetric equations …
Membrane-Enhanced Lamina Emergent Torsional Joints For Surrogate Folds,
2023
Xi’an Jiaotong University
Membrane-Enhanced Lamina Emergent Torsional Joints For Surrogate Folds, Guimin Chen, Spencer P. Magleby, Larry L. Howell
Faculty Publications
Lamina emergent compliant mechanisms (including origami-adapted compliant mechanisms) are me- chanical devices that can be fabricated from a planar material (a lamina) and have motion that emerges out of the fabrication plane. Lamina emergent compliant mechanisms often exhibit undesirable para- sitic motions due to the planar fabrication constraint. This work introduces a type of lamina emergent torsion (LET) joint that reduces parasitic motions of lamina emergent mechanisms (LEMs), and presents equations for modeling parasitic motion of LET joints. The membrane joint also makes possible one-way joints that can ensure origami-based mechanisms emerge from their flat state (a change point) into …
Halloysite Reinforced Natural Esters For Energy Applications,
2023
The University of Texas Rio Grande Valley
Halloysite Reinforced Natural Esters For Energy Applications, Jaime Taha-Tijerina, Karla Aviña, Victoria Padilla-Gainza, Aditya Akundi
Informatics and Engineering Systems Faculty Publications and Presentations
Recently, environmentally friendly and sustainable materials are being developed, searching for biocompatible and efficient materials which could be incorporated into diverse industries and fields. Natural esters are investigated and have emerged as eco-friendly high-performance alternatives to mineral fluids. This research shows the evaluations on thermal transport and tribological properties of halloysite nanotubular structures (HNS) reinforcing natural ester lubricant at various filler fractions (0.01, 0.05, and 0.10 wt.%). Nanolubricant tribotestings were evaluated under two configurations, block-on-ring, and 4-balls, to obtain the coefficient of friction (COF) and wear scar diameter (WSD), respectively. Results indicated improvements, even at merely 0.01 wt.% HNS concentration, …
Glass-Based Biodegradable Pressure Sensor Toward Biomechanical Monitoring With A Controllable Lifetime,
2023
Missouri University of Science and Technology
Glass-Based Biodegradable Pressure Sensor Toward Biomechanical Monitoring With A Controllable Lifetime, Devdatt Chattopadhyay, Jonghyun Park, Chang-Soo Kim
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A New Class of Potentially Implantable Solid-State Sensors is Demonstrated Utilizing Biodegradable Glass as the Main Structural Material. the Device Behavior is Manipulated Via Chemical Decomposition, and Then Physically Disintegrated in a Controlled Manner. It is based on the Capacitive Sensing Mechanism, Comprising an Elastic Insulator between Two Borate-Rich Glass Substrates. This Mesoscale Pressure Sensor is Characterized by a Range of Pressure of Up to 14 MPa in a Phosphate Buffer Solution Environment. the Sensor Exhibits Good Sensitivity and Reversibility Responding to Compressive Pressures and Remains Fully Functional Before a Desired, Sudden Failure Caused by Dissolution. the Operational Lifetime Can …
Selection Of Solidification Pathway In Rapid Solidification Processes,
2023
Missouri University of Science and Technology
Selection Of Solidification Pathway In Rapid Solidification Processes, Nima Najafizadeh, Men G. Chu, Yijia Gu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Rapid Solidification Processing of Alloys Enables the Formation of Exotic Nonequilibrium Microstructures. However, the Interrelationship between the Processing Parameters and the Resulting Microstructure is Yet to Be Fully Understood. in Melt Spinning (MS) and Additive Manufacturing (AM) of Rapidly Solidified Alloys, Opposite Microstructure Development Sequences Were Observed. a Fine-To-Coarse Microstructural Transition is Typically Observed in Melt-Spun Ribbons, Whereas Melt Pools in AM Exhibit a Coarse-To-Fine Transition. in This Paper, the Microstructural Evolutions during These Two Processes Are Investigated using Phase-Field Modeling. the Variation of All Key Variables of the Solid-Liquid Interface (Temperature, Composition, and Velocity) throughout the Entire Rapid Solidification …
Launching A 3d Printing Program For Students: Recommendations And Best Practices For Libraries,
2023
Georgia Southern University Libraries
Launching A 3d Printing Program For Students: Recommendations And Best Practices For Libraries, Wilhelmina Randtke, Lee Bareford
Georgia Library Quarterly
The Georgia Southern University Libraries launched a 3D printing program for students in July 2022. Prior to launch, library employees at two of Georgia Southern University’s campuses investigated options for implementing safe, affordable, and sustainable 3D printing in existing academic libraries without retrofitting costly ventilation systems into existing facilities. This article describes the reasons why the Georgia Southern University Libraries thought that a 3D printing program could fulfill a service need for students across university colleges and departments and outlines some of the challenges, best practices, and unique innovations that the library’s employees experienced throughout the program launch process. The …
Me-Em Enewsbrief, December 2022,
2023
Michigan Technological University
Me-Em Enewsbrief, December 2022, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Department of Mechanical Engineering-Engineering Mechanics eNewsBrief
No abstract provided.
Synthesizing Ti–Ni Alloy Composite Coating On Ti–6al–4v Surface From Laser Surface Modification,
2023
Missouri University of Science and Technology
Synthesizing Ti–Ni Alloy Composite Coating On Ti–6al–4v Surface From Laser Surface Modification, Yitao Chen, Joseph William Newkirk, Frank W. Liou
Materials Science and Engineering Faculty Research & Creative Works
In This Work, a Ni-Alloy Deloro-22 Was Laser-Deposited on a Ti–6Al–4V Bar Substrate with Multiple Sets of Laser Processing Parameters. the Purpose Was to Apply Laser Surface Modification to Synthesize Different Combinations of Ductile TiNi and Hard Ti2Ni Intermetallic Phases on the Surface of Ti–6Al–4V in Order to Obtain Adjustable Surface Properties. Scanning Electron Microscopy, Energy Dispersion Spectroscopy, and X-Ray Diffraction Were Applied to Reveal the Deposited Surface Microstructure and Phase. the Effect of Processing Parameters on the Resultant Compositions of TiNi and Ti2Ni Was Discussed. the Hardness of the Deposition Was Evaluated, and Comparisons with …