Engineering Commons^™

The Effect Of Sample Placement In The Furnace During The Heat Treatment Process Of 7075-T6 Aluminum Alloy On Microstructure, Hardness, And Electrical Conductivity, Donanta Dhaneswara, Hardi Rindharto, Muhammad Syauqi Aqilafif

Journal of Materials Exploration and Findings

This paper reports the effects of sample placement during the heat treatment on the microstructural morphology and mechanical properties of 7075 Al alloy such as hardness value and electrical conductivity. The material was in the formed of Al alloy sheets where samples were machined into a square with dimensions of 1.5 x 1.5 inch. The 7075-T0 Al alloy as samples were given heat treatment by precipitation hardening (aging) at temperature 120°C for 24 hours, so it becomes 7075-T6 Al alloy. Samples were subjected to some mechanical tests and the morphology of the resulting microstructures were characterized by optical microscopy. The …

Contents, Jaka Fajar Fatriansyah

Journal of Materials Exploration and Findings

No abstract provided.

Droplet Dynamics And Heat Transfer During Condensation On Lubricant-Infused Surfaces, Jianxing Sun

McKelvey School of Engineering Graduate Student Theses & Dissertations

Inspired by pitcher plants, a micro/nano- structured solid surface infused with low-surface-tension lubricant constitutes a novel class of biomimetic surfaces—lubricant-infused surfaces (LISs). Unlike solid hydrophobic and superhydrophobic surfaces, a LIS is “hemi-solid and hemi-liquid”. The thin lubricating film can extraordinarily decrease adhesion and avoid contact line pinning between the working fluid and the underlying solid, displaying many desirable properties, such as excellent liquid repellency, suppression of fouling, and self-healing. Hence, LISs are ideal for applications where liquids or contaminants must be efficiently removed from surfaces in harsh environments. For example, LISs can promote stable dropwise condensation of water or low-surface-tension …

Modeling, Analysis, And Simulation To Reveal The Mechanisms Of Ciliary Beating, Louis Woodhams

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cilia are microscopic cellular appendages that help us breathe by clearing our airways, maintain the health of our central nervous system by circulating cerebrospinal fluid, and allow us to reproduce by transporting eggs and propelling sperm cells. Cilia even determine the asymmetry of our internal organs during embryonic development. However, the mechanisms underlying ciliary beating are not fully understood. Questions remain as to how arrays of the motor protein dynein generate the propulsive waveforms observed in cilia and how structural elements within the cilium and its connection to the cell deform during beating. In the current work, mathematical modeling, analysis, …

Testing Oxygenated Microbubbles Via Intraperitoneal And Intrathoracic Routes On A Large Pig Model Of Lps-Induced Acute Respiratory Distress Syndrome, Riaz Ur Rehman Mohammed, Nathaniel T. Zollinger, Andrea R. Mccain, Roser Romaguera-Matas, Seth P. Harris, Keely L. Buesing, Mark A. Borden, Benjamin S. Terry

Department of Mechanical and Materials Engineering: Faculty Publications

With a mortality rate of 46% before the onset of COVID-19, acute respiratory distress syndrome (ARDS) affected 200,000 people in the US, causing 75,000 deaths. Mortality rates in COVID-19 ARDS patients are currently at 39%. Extrapulmonary support for ARDS aims to supplement mechanical ventilation by providing life-sustaining oxygen to the patient. A new rapid-onset, human-sized pig ARDS model in a porcine intensive care unit (ICU) was developed. The pigs were nebulized intratracheally with a high dose (4 mg/kg) of the endotoxin lipopolysaccharide (LPS) over a 2 h duration to induce rapid-onset moderate-to- severe ARDS. They were then catheterized to monitor …

A Physics-Based Modeling Of A Hydraulically Amplified Electrostatic Actuator, Alexandrea Washington, Zakai Olsen, Ji Su, Kwang J. Kim

Mechanical Engineering Faculty Research

The focus of this study is to understand the physical phenomenon of the liquid-based electroactive polymer (EAP) actuator known as the Hydraulically Amplified Self-Healing Electrostatic (HASEL) actuator. Specifically, this study provides data in several areas, including the deformation of the film material, the dynamics of the dielectric liquid, and the electrical conditions within the actuator body. A two-dimensional model was developed in the finite element software, COMSOL Multiphysics, to create a generalized physics-based framework that describes the actuation mechanism. Much of the predictive data agreed well with the experimental data, such as the electrode pull-in occurring at ∼4.5 kV and …

Strain And Strain Rate In Friction Extrusion, Xiao Li, Md Reza-E- Rabby, Anthony Guzman, Glenn Grant, Suveen Mathaudhu, Michah Hinton, Anthony P. Reynolds

Faculty Publications

Friction extrusion is a metal forming process that generates large plastic strains and deformation-induced heating through friction between a rotating die and the material to be extruded. The final deformation state in friction extruded wire has been visualized in previous studies but the distribution and evolution of strain and strain rate inside the solid material have yet to be elucidated. This paper develops an approach that reveals the deformation during the process by visualizing the shape change of the pre-embedded markers in the remnant billet. For the first time, the distribution of steady-state strain and strain rate in friction extrusion …

The Temperature Dependent Mechanical Response Of M250 Maraging Steel And Its Implications On Wire Arc Additive Manufacturing, Frank M. Brinkley Iii

Theses and Dissertations

Wire-arc additive manufacturing (WAAM) is becoming increasingly common for large scale additive manufacturing (AM) applications because of its high deposition rate (2-3 kg/hr.). The rapid temperature changes and subsequent evolution of mechanical properties during AM can lead to large distortion and residual stresses. Finite element modeling of the AM process shows promise to minimize part distortion and residual stresses through improved path planning and process parameter optimization. However, accurate material properties of M250 before and after heat treatment are needed to properly characterize the property evolution from annealed to AM, to aged. Due to limited data on annealed M250, this …

An Investigation Into The Velocity-Dependence Of The Coefficient Of Friction Between Concrete And Maraging Steel, Trace A. Duncan

Theses and Dissertations

This work investigates the velocity-dependent coefficient of friction between concrete and 300 Maraging steel over short displacements. A modified torsional Hopkinson bar is utilized for rotating thin-walled steel rings in contact with a concrete disk under static precompression. Rotational velocity is varied between tests to determine the velocity dependence of the friction coefficient. Normal force is varied between certain tests to determine the pressure dependence of the friction coefficient between the concrete and steel. Three different types of concrete are tested to deduce any composition effect on the friction coefficient. Dry and greased conditions’ impact on the friction coefficient are …

The Effect Of Heat Treatment On Mechanical Properties Of Additively Manufactured 17-4 Ph Stainless Steel, Nicholas Aaron Hopkins

Theses and Dissertations

Additive manufacturing (AM) is used to create geometries otherwise impossible to machine. Topology optimization, microstructural texture control, and the use of lattices could be created through AM to increase performance of systems. Currently research focuses on solution aging of printed 17-4 PH, while other heat treatments are not as heavily studied. This study identifies different heat treatments applied to additively manufactured 17-4 precipitation hardened (PH) and the effects on mechanical properties. This study used quasi-static tension, quasi-static compression, and Charpy V-notch testing to analyze the effects of heat treatment as well as the effectiveness of additive manufacturing compared to traditional …

Ferrous Alloy Manufacturing For The Martian Surface Through In-Situ Resource Utilization With Ionic Liquids Harvested Iron And Bosch Process Carbon, Blake C. Stewart

Theses and Dissertations

As research continues for the habitation of the Lunar and Martian surfaces, the need for materials for construction of structural parts, mechanical components, and tools remains as a major milestone. The use of in-situ resource utilization (ISRU) techniques is critical due to the financial, physical, and logistical burdens of sending supplies beyond low-Earth orbit. The Bosch process is currently in development as a life support system at the National Aeronautics and Space Administration’s (NASA) Marshall Space Flight Center (MSFC) to regenerate oxygen (O2) from metabolic carbon dioxide (CO2) with the byproduct of elemental carbon (C). The Bosch process presents a …

Flow And Thermal Transport In Additively Manufactured Metal Lattices Based On Novel Unit-Cell Topologies, Inderjot Kaur

Theses and Dissertations

The emergence of metal Additive Manufacturing (AM) over the last two decades has opened venues to mitigate the challenges associated with stochastic open-cell metal foams manufactured through the traditional foaming process. Regular lattices with user-defined unit cell topologies have been reported to exhibit better mechanical properties in comparison to metal foams which extend their applicability to multifunctional heat exchangers subjected to both thermal and mechanical loads. The current study aims at investigating the thermal-hydraulic characteristics of promising novel unit cell topologies realizable through AM technologies. Experimental investigation was conducted on four different topologies, viz (a) Octet, (b) Face-diagonal (FD) cube, …

Biodiesel Production From A Non-Edible Source Of Royna (Aphanamixis Polystachya) Oil, Md. Wasikur Rahman, Asim Kumar Mondal, Md Shakil Hasan

Mechanical Engineering Faculty Publications

Background

Rapid consumption of fossil fuels as well as rising environmental deterioration caused by extreme CO2 emissions has become crucial in searching for a clean and renewable energy source such as biodiesel. The current work is an attempt to produce biodiesel from a potential non-edible feedstock of Aphanamixis polystachya, locally known as ‘Royna’ seed oil in Bangladesh.

Methods

Royna oil was extracted from the seed by Soxhlet extraction method. Biodiesel was synthesized by a three-step process: saponification of oil, followed by acidification of the soap, and esterification of the free fatty acid (FFA).

Results

The result presented showed that …

28 Ghz Patch Antenna Array With Reduced Mutual Coupling For 5g Communications Systems, Rahabu F. Mwang’Amba, Hashimu Uledi Iddi

Tanzania Journal of Engineering and Technology (TJET)

A 28 GHz patch antenna array with reduced mutual coupling for 5G communication systems is presented in this paper. Two elements antenna array was simulated with a periodic boundary to represent an infinity array. The antenna array is attached with a pair of the coupled directional coupler with a coupling value of -3.47 dB, and transmission lengths of 3.40 mm and 7.62 mm depending on the antenna array's magnitude and phase coefficient were designed and simulated. A reduced mutual coupling of -31.86 dB compared to -10.75 dB for an array without a decoupling network was observed. The wide scanning angle …

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

Open Educational Resources

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

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

ETD Archive

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

Mechanical Actuation Via Resorbable Materials, Bethany Parkinson

Undergraduate Honors Theses

Resorbable materials—or materials which diffuse into their surroundings—present a promising means of actuating mechanical systems. In current practice, such as in the realm of in vivo surgical devices, resorbable materials are often intended to perform a temporary function and completely dissolve when that function is completed (e.g. resorbable sutures). In this paper, resorbable materials are proposed for use in a different way: as a means for actuating mechanical systems. We create several prototypes which demonstrate that resorbable materials, combined with stored energy, can be used to actuate mechanical systems under several loading conditions and in various applications. We also present …

A Primer On The Factories Of The Future, Noble Anumbe, Clint Saidy, Ramy Harik

Faculty Publications

In a dynamic and rapidly changing world, customers’ often conflicting demands have continued to evolve, outstripping the ability of the traditional factory to address modern-day production challenges. To fix these challenges, several manufacturing paradigms have been proposed. Some of these have monikers such as the smart factory, intelligent factory, digital factory, and cloud-based factory. Due to a lack of consensus on general nomenclature, the term Factory of the Future (or Future Factory) has been used in this paper as a collective euphemism for these paradigms. The Factory of the Future constitutes a creative convergence of multiple technologies, techniques, and capabilities …

Design And Performance Of A Directional Permeability Membrane, Hamidreza Bayat

Mechanical Engineering Research Theses and Dissertations

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

Planning Of Air Conditioner Cooling Load In The Dean Room Of The Faculty Of Engineering And Information Technology University Of Pgri Semarang, Slamet Supriyadi, Irna Farikhah, Suhartono Suhartono

Journal of Materials Exploration and Findings

The specification of the cooling load or chiller in the FTI UPGRIS dean's room currently requires a review of the distribution of cooling air in the room due to the number of electronics and occupants in the room and the size of the air conditioner. Therefore, the room must be taken into account to prevent insufficient cooling load, As a result, it is impossible to reach the desired temperature and humidity set. The FTI Dean's room has an air conditioner with a cooling capacity of 1 unit. It should be able to cover the amount of cooling in the room. …

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Power And Voltage Modelling Of A Proton-Exchange Membrane Fuel Cell Using Artificial Neural Networks, Tabbi Wilberforce, Mohammad Biswas, Abdelnasir Omran

Mechanical Engineering Faculty Publications and Presentations

A proton exchange membrane fuel cell (PEMFC) is a more environmentally friendly alternative to deliver electric power in various applications, including in the transportation industry. As PEMFC performance characteristics are inherently nonlinear and involved, the prediction of the performance in a given application for different operating conditions is important in order to optimize the efficiency of the system. Thus, modelling using artificial neural networks (ANNs) to predict its performance can significantly improve the capabilities of handling the multi-variable nonlinear performance of the PEMFC. However, further investigation is needed to develop a dynamic model using ANNs to predict the transient behavior …

Energy Consumption Analysis Using Measured Data From A Net-Zero Energy Commercial Building In A Cold And Dry Climate, Sukjoon Oh, John F. Gardner

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Zero-energy buildings have a critical role in reducing global energy use and greenhouse gas emissions. However, few studies have analyzed net-zero energy commercial buildings using measured energy use such as whole-building level and end-use level data. This paper presents an energy consumption analysis for the first net-zero energy commercial building in Idaho, U.S., in a cold and dry climate using measured end-use data from this building as well as measured whole-building energy use. Monthly bill data analysis, end-use data analysis, and Energy Use Intensity (EUI) analysis were conducted. The combined analysis of this study shows that the HVAC system was …

Out-Of-Plane Load-Bearing And Mechanical Energy Absorption Properties Of Flexible Density-Graded Tpu Honeycombs, Ibnaj Anamika Anni, Kazi Zahir Uddin, Nicholas Pagliocca, Nand Singh, Oyindamola Rahman, George Youssef, Behrad Koohbor

Henry M. Rowan College of Engineering Departmental Research

Honeycomb structures are widely used in applications that require excellent strain energy mitigation at low structural weights. The load-bearing and energy absorption capacity of honeycomb structures strongly depend on their cell wall thickness to edge ratios. This work studies the mechanical response and strain energy absorption characteristics of hexagonal honeycomb structures with various cell wall thicknesses in response to out-of-plane loading conditions. Honeycomb structures with various nominal densities are first additively manufactured from flexible thermoplastic polyurethane (TPU). A comprehensive experimental study characterized the mechanical strength, energy absorption performance, and the strain recoverability of the structures. Density-graded structures are then fabricated …

Data-Driven Research On Engineering Design Thinking And Behaviors In Computer-Aided Systems Design: Analysis, Modeling, And Prediction, Molla Hafizur Rahman

Graduate Theses and Dissertations

Research on design thinking and design decision-making is vital for discovering and utilizing beneficial design patterns, strategies, and heuristics of human designers in solving engineering design problems. It is also essential for the development of new algorithms embedded with human intelligence and can facilitate human-computer interactions. However, modeling design thinking is challenging because it takes place in the designer’s mind, which is intricate, implicit, and tacit. For an in-depth understanding of design thinking, fine-grained design behavioral data are important because they are the critical link in studying the relationship between design thinking, design decisions, design actions, and design performance. Therefore, …

Geometric Analysis Of Insect Wing Vein Network, Jacob White, Ying Hu, Sangjin Ryu, Seunghee Kim, Haipeng Zhang

Department of Mechanical and Materials Engineering: Faculty Publications

An insect wing consists of a thin membrane supported by a system of veins, and flow of blood through the system of veins is critical for maintaining healthy insect wings. Better understanding of the insect wing vein circulation requires to know how the efficiency of blood flow in an insect wing relates to the geometric shape of the vein. Our investigation of the wing vein network of a dragonfly Anax junius follows the idea of Murray’s law, which is established in the study of efficiency of the vein network and the geometric shape of the vein. Instead of using the …

Infrared And Fluorescent Thermal Imaging And Thermal Transport Characterization Of Engineering Devices And Systems, Swapnil Suryakant Salvi

Mechanical and Aerospace Engineering Dissertations - Archive

Infrared (IR) thermal imaging is widely used for non-contact temperature measurement in engineering. IR camera detects thermal emissions from the target surface in a certain wavelength range, which, using the known surface emissivity, can be converted to a pixel-by-pixel temperature map. Fluorescence imaging also works along similar lines. This Ph.D. dissertation contributes towards thermal imaging and thermal transport characterization in engineering devices/systems using infrared and fluorescence imaging. In the first two parts of this work, infrared thermal imaging is used for measuring thermal conductivity of thin wires and for spotting unusual activities in a three-dimensional integrated circuit (3D IC). In …

In-Situ Observation Of Extrusion Process In Thermoplastic Material Extrusion Based Additive Manufacturing, Ye Hong

Mechanical and Aerospace Engineering Dissertations - Archive

In thermoplastic material extrusion-based additive manufacturing, solid polymer filaments are fed into extruders to generate extrudates that are needed to build 3D plastic products. There is a finite gap between the inner surface of an extruder and the edge of a filament. This gap facilitates the insertion and translation of the filament inside the extruder. However, it is still not clear how the gap is filled during the extrusion. The lack of this information makes it difficult to model the temperature distribution and flow profile during the extrusion. In this work, we built experimental apparatus to directly observe the gap-filling …

Multi-Objective Aero/Mechanical Design Optimization Of Gp Turbine Blades Platform Contour Using Adjoint Solver And Impact On Secondary Losses, Mostafa Soliman

Mechanical and Aerospace Engineering Dissertations - Archive

Gas Turbines Hot Gas Path components represent the major contribution to generating power in Gas Turbines They are the components that mainly extract power from hot gasses that come out of the combustion Chamber (Combustor). Due to harsh temperature and environment, these components are vulnerable to high thermal and mechanical stresses which affect its durability, life, and efficiency. Hot Gases go through these components can reach very high max temperature. Max blade alloy metal temp in Gas Path blades can reach 1800-1900 F. Because of these severe operation conditions, a very careful prediction of stresses, thermal distribution, losses and flow …