Mechanical Engineering Commons^™

Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells, Juan P. Herrera, Jules Freeman, Achyuth Ravilla, Ilke Celik

Student Research Symposium

Perovskite solar cells (PSCs) have emerged as a promising option for solar energy generation. However, it is essential to consider the environmental impact of these innovative photovoltaic (PV) technologies as the industry moves towards commercialization. Researchers are currently exploring ways to recycle PSCs to recover valuable materials and reduce their environmental impact at the end of their life. To ensure the sustainability of PSCs, this study evaluates and compares the environmental impacts of five recently developed recycling approaches. The Tool for Reduction and Assessment of Chemicals (TRACI) method was utilized to measure environmental impacts in categories such as acidification (kg …

Pulse Modulation In Braided Pneumatic Actuators Mimics Contractile Behavior Of Biological Muscles, Mohamad Elzein

Student Research Symposium

Advancements in robotics and bioengineering aim to emulate biological muscle systems through robotic actuators, blending mechanical strength with biological adaptability. A lesser-explored aspect is mimicking the pulse-like control characteristic of biological muscles, which contract in response to action potentials from motoneurons, with muscle contractile force relying heavily on the timing between these potentials. This study explores the effect of pulse lengths and the gaps between pulses on braided pneumatic actuators (BPAs), which mimic the nonlinearity and dynamic response of biological muscles. It hypothesizes that artificial muscles utilizing pulse-based control will exhibit a similar force dependency on the intervals between pulses …

Deriving Analytical Design Constraints For Absolute & Relative Encoding Schemes In Functional Subnetworks, Cody W. Scharzenberger-Braet, Alexander Hunt

Student Research Symposium

As neural networks have become prolific solutions to modern problems, there has been a congruent rise in the popularity of the numerical machine learning techniques used to design them. While they are highly generalizable, numerical methods tend to produce networks that act as inscrutable “black boxes,” making it difficult to interpret their behavior. One solution to the problem of network transparency is to use analytical techniques, but these methods are underdeveloped compared to their numerical alternatives. In order to enhance the viability of analytical techniques, this work extends previous efforts to quantify the impact that non-spiking neural encoding schemes have …

Studying The Production Of Nanocelluloses, Shohzodbek Abduvahobovich Rashidov, Elmurod Abduqodirovich Egamberdiev, Sadritdin Maxamatdinovich Turabdjanov

Technical science and innovation

Nanoscience is a broad field that includes nanophysics and nanochemistry. Nanotechnologies are aimed at obtaining nanoparticles with new properties and creating materials and devices based on them. This is one of the modern trends in the development of science in the 21st century.

Based on the study of information about nano-sized materials, the mechanisms of their production and changes in their properties, we will consider the technology for producing nanocellulose from organic substances, i.e. from cellulose. The article describes a technology that examines devices for producing nanocellulose and the principles of their operation, as well as a combined method of …

The Results Of Hydrodynamic Studies On Stationary And Non-Stationary Filtration Modes On The Example Of The Kruk Deposit, Nazirila Maxmudov, Nargiza Akhmedova, Saodat Shukurullaeva

Technical science and innovation

The article presents the results of gas-hydrodynamic studies at the Kruk field, using methods of steady selection and pressure recovery based on stationary and unsteady modes, which were carried out according to the well research methodology, which prescribes the separation into phases of the entire productive flow of the gas-liquid mixture in the separator, in which, under various separation modes, the amount of liquid phase, namely gas condensate and formation water, was separated and measured.. A mobile full-flow separation installation was used as a separator. The condensate output was measured in a calibrated container using a measuring ruler, which made …

Modeling Of Continuous Stirred Tank Reactor For Esterification Process, Olimjon Rikhsiboyevich Maksudov, Abdulaziz Nodirbek Ogli Bakhtiyorov, Orifjon Olimovich Zaripov, Аdhаm Tilovovich Norkobilov

Technical science and innovation

This paper presents a comprehensive study on the synthesis of ethyl acetate through the esterification of acetic acid with ethanol using a continuous stirred tank reactor (CSTR). Ethyl acetate is a significant solvent in various industries due to its eco-friendly characteristics and economic efficiency. The study develops a detailed mathematical model focusing on the operating of the CSTR to enhance the understanding of the reaction kinetics and thermodynamics in a continuous processing environment. The reactor model was validated with experimental data to optimize process parameters, aiming to improve yield and selectivity. Key variables such as reactant ratios, and operational temperatures …

Presence Of Atheromatous Plaques And Theirs Effects On The Blood Flow, Belhocine Mostefa Bm, Amrani Hichem Ah, Fedaoui Kamel Dr, Mazouz Hammoudi Mh

Emirates Journal for Engineering Research

The paper utilizes a finite element method to study both the blood flow and atheromatous plaques. Specifically, the COMSOL finite element package is employed to achieve a fluid model. COMSOL is a powerful finite element tool commonly used in various research and industrial domains to study multiphysics problems. The focus of the investigation is on the geometric aspects of the atheromatous plaques. The study considers different forms and arrangements of stenosis, taking into account the irregularities formed by various shapes of the plaques and the resulting flow patterns. The key findings of the research suggest that the pressure and velocity …

Application Of Biochar / Bentonite Based Admixtures In Reinforced Concrete For Corrosion Prevention, Jacob Fleury

Graduate Theses & Non-Theses

Reinforced concrete systems are in many sectors of infrastructure. Due to a combination of elevated compressive strength from the cement and aggregates and tensile strength from the reinforcing steel, reinforced systems are favorable in construction applications where high strength is desired. However, while reinforced concrete is in service, it can be introduced to contaminants that cause corrosion. Contaminants can leach through the porous matrix of the concrete structure and influence initiation of corrosion products on reinforcement. Corrosion is the primary cause for advanced deterioration of concrete structures. Concrete deterioration has promoted research efforts for the protection of future systems. This …

Analyzing Heat Generated From Electro-Osmotic Flow Utilizing Computational Fluid Dynamics, Jordan Elizabeth Grothe

Honors Thesis

Without extensive vascularization, the transfer of fluid and nutrients through human tissue is limited to diffusion and weak interstitial flow. Electroosmosis, or the flow of fluid driven by an electrical field, has become a promising solution. Scientists have begun applying electricity to human tissue to promote stronger interstitial flow; however, optimization of this process has proven to be a challenge due to ohmic heating. Cells function within a small range of temperatures and exposure to voltages exceeding the threshold will cause cells to degrade and die prematurely. This research seeks to better understand and quantify the range of voltage where …

A Redox-Reversible A/B-Site Co-Doped Bafeo3 Electrode For Direct Hydrocarbon Solid Oxide Fuel Cells, Haixia Li, Wanhua Wang, Kai Zhao, Ka-Young Park, Taehee Lee, Ramin Babazadeh Dizaj, Andreas Heyden, Dong Ding, Fanglin Chen

Faculty Publications

Solid oxide fuel cells (SOFCs) can directly convert the chemical energy in fuel to electrical energy with fuel flexibility; however, the conventional nickel-based anodes face great challenges due to coking upon direct oxidation of hydrocarbon fuels and redox instability. Thus, developing new anode materials which can provide high coking resistance as well as redox stability is crucial. In this work, Ba_0.6La_0.4Fe_0.8Mo_0.1Ni_0.1O_3−δ (BLFMN) has been synthesized in air using a sol–gel combustion method, resulting in a dual phase consisting of a cubic BLFMN main phase and scheelite BaMoO_{4 …}

Comparative Analysis Of Cutting Forces In Axial-Compliant And Rigid Chamfering Tools, Sultonmurod Bekpulatovich Normatov, Oybek Tuyboyov, Azimjon Axror O'G'Li Pardayev, Alisher G‘Ayratjon Ogli Boratov, Shohjahon Tuxtasin Ogli Abdullayev

Technical science and innovation

This study delves into the analysis of cutting forces in axial-compliant systems, focusing specifically on the comparison between axially spring-compensated 90° conical tools and rigid chamfering tools. The research incorporates a predictive model for chamfer size calculation in the axially spring-compensated tools, verified through experimental tests on representative parts. The study aims to control chamfer size within tolerances by adjusting process conditions and optimizing processing efficiency. By exploring the fundamentals of the chamfering process, this research offers insights into breaking sharp edges on components with positional errors and shape deformations, with a particular emphasis on aero-engine casings. The integration of …

Data-Driven And Cell-Specific Determination Of Nuclei-Associated Actin Structure, Nina Nikitina, Nurbanu Bursa, Matthew Goelzer, Madison Goldfeldt, Chase Crandall, Sean Howard, Janet Rubin, Anamaria Zavala, Aykut Satici, Gunes Uzer

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Quantitative volumetric assessment of filamentous actin (F-actin) fibers remains challenging due to their interconnected nature, leading researchers to utilize threshold-based or qualitative measurement methods with poor reproducibility. Herein, a novel machine learning-based methodology is introduced for accurate quantification and reconstruction of nuclei-associated F-actin. Utilizing a convolutional neural network (CNN), actin filaments and nuclei from 3D confocal microscopy images are segmented and then each fiber is reconstructed by connecting intersecting contours on cross-sectional slices. This allows measurement of the total number of actin filaments and individual actin filament length and volume in a reproducible fashion. Focusing on the role of F-actin …

Bottling Automation System, Dylanie Tippit

Honors College Theses

This report details the complete design of an automated bottling system. Each bottle is 5.97 centimeters tall and has an outer diameter of 3.81 centimeters. The goal of the project is to successfully fill and cap twelve bottles in under three and a half minutes. The system will have two conveyors in series, a water dispenser, an electrolyte dispenser, capping station, Human Machine Interface (HMI) and Allen Bradley programmable logic controller (PLC). The water and electrolyte dispenser will have two ball valves in series, with the desired amount of volume to dispense the designated liquid. The capping station will be …

Non-Contact Wind Turbine Blade Crack Detection Using Laser Doppler Vibrometers, Ali Zabihi, Farhood Aghdasi, Chadi Ellouzi, Nand Kishore Singh, Ratneshwar Jha, Chen Shen

Henry M. Rowan College of Engineering Departmental Research

In response to the growing global demand for both energy and a clean environment, there has been an unprecedented rise in the utilization of renewable energy. Wind energy plays a crucial role in striving for carbon neutrality due to its eco-friendly characteristics. Despite its significance, wind energy infrastructure is susceptible to damage from various factors including wind or sea waves, rapidly changing environmental conditions, delamination, crack formation, and structural deterioration over time. This research focuses on investigating non-destructive testing (NDT) of wind turbine blades (WTBs) using approaches based on the vibration of the structures. To this end, WTBs are first …

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Physics Undergraduate Honors Theses

Mechanical Exfoliation

Dna/Carbon Nanotube Hybrid Structure And Their Translocation Through A Nanochannel, Daniel Christoffel Viljoen

Graduate Theses and Dissertations

DNA sequencing is of major importance as it is used in fields such as species differentiation, personalized medicine and food safety. Currently sequencing by synthesis is the most popular commercial method of sequencing DNA while Oxford nanopore’s protein based nanopores are the only portable commercial method. Current nanopore based devices have three main issues: Spacial resolution, translocation rate versus sensor strength and dealing with the persistence length of ssDNA. This thesis contributes to ongoing research that aims to create a nanochannel with integrated sensor based sequencing device. The project has two main objectives. The first objective is to improve the …

Environment And Response Of 3d-Encapsulated Mesenchymal Stem Cells To Mechanical Loading, Augustus Greenwood

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis explores the micromechanical environment induced when cyclically compressing hydrogels via finite element modeling and experimentally on the impact of loading on mesenchymal stem cells (MSCs) when encapsulated withing 3D hydrogel matrices. Degenerative joint diseases, characterized by cartilage degradation, present significant challenges due to cartilage's limited self-repair capacity. Innovative approaches, including stem cell-based therapies and engineered biomaterials, have emerged as promising strategies for cartilage repair and regeneration. This work specifically investigates the calibration of a bioreactor, the uniformity of load response across the hydrogel constructs via finite element modeling (FEM), and the stress response of MSCs subjected to various …

Numerical Investigation Of Supersonic Flow Over A Wedge By Solving 2d Euler Equations Utilizing The Steger–Warming Flux Vector Splitting (Fvs) Scheme, Mitch Wolff, Hashim H. Abada, Hussein Awad Kurdi Awad Kurdi Saad

Mechanical and Materials Engineering Faculty Publications

Supersonic flow over a half-angle wedge (θ = 15°) with an upstream Mach number of 2.0 was investigated using 2D Euler equations where sea level conditions were considered. The investigation employed the Steger–Warming flux vector splitting (FVS) method executed in MATLAB 9.13.0 (R2022b) software. The study involved a meticulous comparison between theoretical calculations and numerical results. Particularly, the research emphasized the angle of oblique shock and downstream flow properties. A substantial iteration count of 2000 iteratively refined the outcomes, underscoring the role of advanced computational resources. Validation and comparative assessment were conducted to elucidate the superiority of the Steger–Warming flux …

Rasc-Al Large Scale Lunar Crater Prospector, Austin Arnold, Coleman Alvarez, Mark Suberu

Senior Design Project For Engineers

The purpose of this project is to design a conceptual layout of a lunar rover capable of exploring craters at the lunar south pole. The rover should be autonomous and capable of self-sustainment for at least one year in extreme cold and darkness. While determining the location and accessibility of water ice and other volatiles within the crater. This document will contain all information related to the team's conceptual design. Including research, component selection, electrical design, and mechanical design.

Lunar Rascals Video: https://www.youtube.com/watch?v=MdcjzVMtzaI

Emulsion Stability, Rheological Properties, And Combustion Characteristics Of Water-Jojoba Biofuel Emulsion, Ihab Mohamed Helal

Theses

This thesis comprehensively investigates the stability, rheological properties, and engine performance implications of Water in Jojoba Biodiesel (WJBD) emulsion. The research delves into multiple aspects, including the influence of diverse surfactants and water concentrations on emulsion stability. It also yields valuable insights into the development of stable water in jojoba biodiesel emulsions, specifically tailored for diesel engines. These insights contribute significantly to the body of knowledge of positioning emulsion fuels as viable alternative to traditional diesel fuels. The anticipated benefits include notable reductions in emissions, improvement in combustion efficiency, and lower production cost. Importantly, this study underscores the critical importance …

Heat Sink Integrating Phase Change Materials (Pcms) For Cooling High Power Electronic Devices, Mohammad Sameer Qasem

Theses

This research explores the numerical analysis of phase change materials (PCMs) heat sinks, focusing on high heat flux dissipation applications, e.g. electronics cooling. Both 2D and 3D numerical models using gallium and paraffin RT31 as PCMs are considered within a heat sink design framework featuring a rectangular cavity and dual opposing vertical copper walls serving as fins to dissipate heat from the hot sink base that receives heat from the heat source. The inclusion of a Triply Periodic Minimal Surface (TPMS) ‘Primitive’ structure as an in-fill thermal conductivity enhancer (TCE) in the case of the gallium heat sink, and a …

Transfer-Learning-Enhanced Regression Generative Adversarial Networks For Optimal Evtol Takeoff Trajectory Prediction, Shuan Tai Yeh, Xiaosong Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric vertical takeoff and landing (eVTOL) aircraft represent a crucial aviation technology to transform future transportation systems. The unique characteristics of eVTOL aircraft include reduced noise, low pollutant emission, efficient operating cost, and flexible maneuverability, which in the meantime pose critical challenges to advanced power retention techniques. Thus, optimal takeoff trajectory design is essential due to immense power demands during eVTOL takeoffs. Conventional design optimizations, however, adopt high-fidelity simulation models in an iterative manner resulting in a computationally intensive mechanism. In this work, we implement a surrogate-enabled inverse mapping optimization architecture, i.e., directly predicting optimal designs from design requirements (including …

Implementation Of Explainable Ai For Bearing Fault Classification, Mohammad Mundiwala

Honors Scholar Theses

It is difficult to overstate the impact of artificial intelligence (AI) over the past decade. The rapid expansion of machine learning has stimulated a race to deploy AI in all facets of life, one such domain being machine health monitoring. There is no doubt that machine learning excels in prediction accuracy, but oftentimes, these models are cryptic and fail to provide valuable insight into their decisions. This paper presents an overview of a neural network and what it means to learn. Next, two distinct Explainable AI (XAI) techniques will be presented: Gradient Class Activation Mapping and SimplEx . Finally, these …

Development Of A Multi-Use Modular Microfluidic Platform Using 3d Printing, Carson Emeigh

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Microfluidic lab-on-a-chip (LoC) technology has driven numerous innovations due to their ability to perform laboratory-scale experiments on a single chip using microchannels. Although LoC technology has been innovative, it still suffers from limitations related to its fabrication and design flexibility. Typical LoC fabrication, with photolithography, is time consuming, expensive, and inflexible. To overcome the limitations of LoC devices, modular microfluidic platforms have been developed where multiple microfluidic modules, each with a specific function or group of functions, can be combined on a single platform. Modular microfluidics have overcome some of the limitations of LoC devices, but currently, their fabrication is …

Flow Characterization With Acoustic Emission Sensing, Jackson Marsh

Mechanical Engineering Undergraduate Honors Theses

Acoustic emissions (AE) allow for non-intrusive sensing into many types of systems. In systems where there is flow of some type, AE is very useful as these types of systems can be characterized in many ways from the collisions or creation of the flow. Correctly setting up the AE system is extremely important. Failure to do so results in imprecision and inaccurate data being collected. Because of this synchronization techniques, sensor configurations, and data acquisition systems must all align. This can be done with off-the-shelf, commercial systems, but this does not allow for customization and the ability to tailor the …

Effects Of Process-Induced Defects On The Corrosion Of Additively Manufactured Stainless Steel 304l, Leila Saberi, Frank W. Liou, Mehdi Amiri

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This Study Investigates the Impact of Process-Induced Defects Such as Gas Pores, Lack of Fusions, and Surface Roughness on Corrosion Behavior of Stainless Steel 304L (SS304L) Fabricated by Laser Powder Bed Fusion Additive Manufacturing. Specimens Are Printed with Optimized Process Parameters but Selected from Different Locations on the Build Plate. Parallel and Perpendicular Surfaces to the Build Direction Are Investigated and Compared with Corrosion Properties of Wrought SS304L in 5 Wt% NaCl. the Results Reveal Significant Difference in Corrosion Behavior among Specimens Due to Variations in their Defect Features. Pitting Potential, Pit Initiation, and Growth Rates Are Found to Be …

Effect Of Pre-Heating On Residual Stresses And Deformation In Laser-Based Directed Energy Deposition Repair: A Comparative Analysis, Usman Tariq, Sung Heng Wu, Muhammad Arif Mahmood, Michael M. Woodworth, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser-Directed Energy Deposition (DED), a Metal Additive Manufacturing Method, is Renowned for its Role in Repairing Parts, Particularly When Replacement Costs Are Prohibitive. Ensuring that Repaired Parts Avoid Residual Stresses and Deformation is Crucial for Maintaining Functional Integrity. This Study Conducts Experimental and Numerical Analyses on Trapezoidal Shape Repairs, Validating Both the Thermal and Mechanical Models with Experimental Results. Additionally, the Study Presents a Methodology for Creating a Toolpath Applicable to Both the DED Process and Abaqus CAE Software. the Findings Indicate that Employing a Pre-Heating Strategy Can Reduce Residual Stresses by over 70% Compared to No Pre-Heating. However, Pre-Heating …

Thermal Conductivity Of Thin Porous Ceramic Coatings: An Analytical And Experimental Study, Lei Zhao

Theses and Dissertations

An analytical model of the thermal conductivity of the porous yttrium-stabilized zirconia (YSZ) layer used in the thermal barrier coatings (TBCs) is presented. Such high-temperature resistant coatings are essential to protect the metallic components of gas turbine engines. The model calculates the conductivity based on the coating's porosity, pore size distribution, and pore morphology, including the individual pore cross-section area, aspect ratio, and orientation, which are extracted from the scanning electron microscopy images. The model was verified through comparisons with numerical simulation results from a multiphysics software tool. A laser temperature gradient test was performed to validate the analytical model …

Summonable Construction Delivery Robot, Kevin M. Lewis

Honors Capstones

In many different construction industries, there is a need for tools, parts, and other necessary items to be transported quickly and efficiently over various types of terrain. Human resources have often been used to address these needs, which can become very time and cost inefficient over long periods. The design proposal here is aimed at addressing this need by developing an autonomous outdoor mobile robot based on a quadrupedal robot design. This approach differs by incorporating a wheeled and quadrupedal hybrid actuation system that provides terrain negotiation and speed at the appropriate times. The team uses Robot Operating System (ROS) …

Novel Vector Assignment Approach For Inherent Strain Modeling Of Laser Powder Bed Fusion Manufacturing, Lucas M. Morand

All Dissertations

The expansion of the design space due to additive manufacturing (AM) has been a large motivator for the success of this family of processes. Despite the complexity of the physics in metal laser powder bed fusion AM causing significant stresses and strains in finished parts, the design advantages and subsequent performance improvements continue to drive the expansion of AM. Because the trial-and-error approach to AM part development is cost prohibitive, simulation of prints has become crucial. However, full thermo-mechanical simulation is susceptible to the same pitfall of time and computational cost in order to attain part-scale results. The development of …