Mechanical Engineering Commons^™

Building Performance - Societal Drive, Programme And Symposium, Joseph Little, Patrick Daly

Articles

Society is increasingly looking at the construction industry to mitigate the environmental crisis and solve the housing crisis through wholesale embrace of three broad sets of challenges. The MSc in Building Performance (Energy Efficiency in Design) (MSc BP(EED)) was created in 2017 to provide significant upskilling in the knowledge, skills, and software applications of building design professionals so that they can meet these challenges, while creating compliant, sustainable, super-low energy, new and renovated buildings. The delivery of the programme supports upskilling of employed building design professionals at Masters level, encouraging a minority to develop their capacity and interest in research …

Calorimetric Measurements Of Lunar Regolith Simulant And Water. An Experimental Study Correlating Weight Percent Water And Temperature Change Through Periods Of Phase Change., George B. Johnson

Dissertations, Master's Theses and Master's Reports

Permanently Shaded Regions (PSRs) are cold traps located around the lunar south pole that have been confirmed to contain possible interesting quantities or volatiles such as H2O, CO2, SO2, CH4, and others. [1] The identification of these volatiles on the lunar surface was a critical step in the development of NASA’s strategic goals for scientific discoveries, sustained space travel and exploration, and re-establishing a human presence on the moon. These volatiles are vital to the future of operating in and exploring space. The LCROSS impact revealed the existence of these resources in PSRs but more information is needed about the …

Symmetric Or Asymmetric Glide Resistance To Twinning Disconnection?, Mingyu Gong, Houyu Ma, Kunming Yang, Yue Liu, Jian-Feng Nie, Jian Wang

Department of Mechanical and Materials Engineering: Faculty Publications

Successive gliding of twinning disconnections (TDs) creates three-dimensional twins in parent crystal and accommodates shear deformation. It is generally recognized that TD is subject to the same Peierls stress as it glides forward or backward because of its dislocation character and the twofold rotation symmetry of the twin plane. Based on atomistic simulations, we demonstrate that the glide of TDs may be subject to a symmetric or asymmetric resistance corresponding to step character, symmetric resistance for A/A type steps but asymmetric resistance for A/B type steps, where A and B represent crystallographic planes in twin and matrix. Furthermore, we experimentally …

A Preliminary Study Of Electrode Geometry Impact On Spark Discharge Processes, Hongyang Shangguan

Electronic Theses and Dissertations

The ever-growing demands to meet the exhaust emission regulations and fuel economy requirements have driven the development of modern spark ignition (SI) engines towards lean/diluted combustion strategies and engine downsizing. Currently, the transistor coil ignition (TCI) system is still the dominant ignition system applied in SI engines. This work investigates the effects of electrode diameters on the spark discharge characteristics.

In this study, different electrode diameters (0.2 mm, 0.7 mm, 1.5 mm, and 3.5mm) are used. The electrical waveforms of the discharge process are recorded, including the breakdown voltage, the glow voltage, and the secondary current. Results show that the …

Redesign And Benchmarking Of Electric Vehicle Batteries For Demanufacturing For Secondary Life Applications In The Circular Economy, Abhay Singh Rathaur

Electronic Theses and Dissertations

As per the latest records, the transportation sector is the second largest in energy consumption and plays a major role in air pollution and co2 emission. One solution to curb this pollution and release of hazardous gases is li-ion batteries by electrifying the vehicles. However, these batteries have one factor over here: once EV batteries reach 70-80% charge holding capacity, they are not good enough for traction in the vehicle. Therefore, replacing these batteries with a new ones is necessary. However, these discarded batteries have enough charge holding capacity, which can be used in secondary applications called second- …

อุปกรณ์ขับเคลื่อนนิ้วมือแบบยืดหยุ่นชนิดโครงข่ายโพรงอากาศโดยการพิมพ์ 3 มิติสำหรับงานกายภาพบำบัด, ชัยวัฒน์ มุสิกะปาน

Chulalongkorn University Theses and Dissertations (Chula ETD)

โดยปรกติทั่วไประบบช่วยเหลือการทำงานหลักของมือเป็นสิ่งจำเป็น และขาดไม่ได้ในการช่วยเหลือผู้ป่วยในการดำเนินกิจกรรมในชีวิตประจำวันของพวกเขา เป็นเวลาหลายปีที่ soft robot ส่วนนิ้วมือถูกนำมาใช้ช่วยเหลือผู้ป่วยที่รอดชีวิตจากโรคระบบทางเดินประสาทอันมีผลทำให้กล้ามเนื้อมีความผิดปรกติ และระบบประสาทเสียหาย เช่น โรคหลอดเลือดในสมอง และโรคพาร์กินสัน ในขณะเดียวกันมีการนำ soft robot มาใช้รองรับกับโรคการอักเสบของกล้ามเนื้อ เช่น โรคเอ็นข้อมืออักเสบ (de Quervain) และการกระตุ้นที่นิ้วมือ โดยในงานนี้ได้นำเสนอแบบชิ้นงานของ soft robot จากการพิมพ์ 3 มิติแบบเต็มชิ้นที่ปราศจากกระบวนการหล่อขึ้นรูป และใช้วัสดุเดียวในการพิมพ์ นอกจากนี้ชิ้นงานถูกออกแบบด้วยเทคนิคเครือข่ายโพรงอากาศหลายหน่วย (MC Network) ที่มีความยาว 122 มม. โดยการพิมพ์ 3 มิติแบบเต็มชิ้นเพื่อทำการเปรียบเทียบกับ soft robot อื่นโดยวิธีการหล่อขึ้นรูปที่มีความยาว 130 มม. ในขณะที่ปริมาณการปล่อยแรงดันลมในการทดลอง คือ ระหว่าง 100 kPa ถึง 200 kPa สำหรับการงอนิ้วมือ และพยุงการกำมือ ผลการทดลองแสดงประสิทธิภาพในการงอในระยะการเคลื่อนไหวของนิ้วมือ (ROM) นอกจากนี้ยังทำการทดลองควบคุมการงอของข้อต่อนิ้วมือที่สัมพันธ์กับเซนเซอร์ Electromyography (EMG) เมื่อทำงานตรวจพบการหดตัว และการยืดตัวของกล้ามเนื้อ สุดท้ายนี้งานนี้ได้เสนอแนะแนวคิดเกี่ยวกับการออกแบบ และการสร้าง soft robot ส่วนนิ้วมือเพื่อใช้ในการทำกายภาพบำบัดในการแพทย์

Human Ergonomic Simulation To Support The Design Of An Exoskeleton For Lashing/De-Lashing Operations Of Containers Cargo, Francesco Longo, Antonio Padovano, Vittorio Solina, Virginia D' Augusta, Stefan Venzl, Roberto Calbi, Michele Bartuni, Ornella Anastasi, Rafael Diaz

VMASC Publications

Lashing and de-lashing operations of containers cargo on board containerships are considered as quite strenuous activities in which operators are required to work continuously over a 6 or 8 hours shift with very limited break. This is mostly because containerships need to leave the port as soon as possible and containers loading and unloading operations must be executed with very high productivity (stay moored in a port is a totally unproductive time for a ship and a loss-making business for a shipping company). Operators performing lashing and de-lashing operations are subjected to intense ergonomic stress and uncomfortable working postures. To …

An Investigative Design Of Gas Jet Nozzles And Their Flow Field Effect On Spatial Distribution, Adam Phengsomphone

Honors Undergraduate Theses

Within this study, the presented material has the objective of providing insight and design characteristics for gas jet nozzles that experimentalists and researchers should consider when utilizing this experimental method. Firstly, this study introduces the developing history and necessity for gas jet experiments and its well-known drawbacks, eventually leading to recent studies and founded knowledge regarding the nozzle geometry dependence on the flow field. The simulation methodology of this study will be presented where the discretization of the computational domain, selection of the flow physics model, and overall design of the nozzle geometry is explained and justified. The flow field …

An Introduction To The Comparison Of Seismocardiography And Phonocardiography, Anna C. Voyatzoglou

Honors Undergraduate Theses

The intent of this thesis is to lay groundwork for examining the relationship between seismocardiography (SCG) and phonocardiography (PCG). Both are methods of measuring and describing heart mechanical function. SCG is described as chest vibrations while the heart beats, and PCG is described as acoustic chest surface signal believed to represent the heart valves opening or closing. SCG and PCG have both been used separately in clinical and research settings, but there is currently no clear comparison between the two. Therefore, there has been no way at the present to understand how one signal might inform the other. This study …

Probing The Effect Of Hyperglycemia On Endothelial Force Generation And Transmission, Jovani J. Gutierrez

Honors Undergraduate Theses

This thesis intends to utilize biomechanics to study the endothelial biomechanical response in a static hyperglycemic microenvironment. Hyperglycemia is a diabetic condition with abnormally high levels of glucose in the bloodstream. The effects of hyperglycemia over time lead to vascular complications resulting in patients being more prone to cardiovascular diseases. Current studies have focused on the molecular mechanisms affected by hyperglycemia; however, the mechanical mechanisms by which hyperglycemia causes vascular structural and functional changes are understudied. Therefore, to study the effects of hyperglycemia in the endothelium, Human Umbilical Vein Endothelial Cells (HUVEC) were cultured under three glucose conditions: normal glucose …

Design And Development Of Medical Devices For Multifaceted Applications, Madisyn Messmore

Honors Undergraduate Theses

The fields of biotechnology and biomedical sciences are rapidly evolving and involve the constant growth of knowledge. As a consequence, engineering design has to also remain at the cutting edge in order to not inhibit the growth of these fields. This study focuses on engineering design and analysis as it pertains to the field of biotechnology, at every step of the engineering process. More specifically, how the engineering design and analysis approach can assist in solving medical problems relating to bone diseases and biomaterials. The first part of the study focuses on a project to design and manufacture a novel …

Heat Transfer And Fluid Flow Analysis Of Molten Salt Heat Exchanger In A Novel Thermolysis Reactor Design For The Thermochemical Cu-Cl Cycle For Hydrogen Production, Ehsan Armoudli

Electronic Theses and Dissertations

Among the new methods for producing clean hydrogen, the thermochemical copper-chlorine (CuCl) cycle is one of the most promising due to the relatively high exergy and energy efficiencies and lower temperature requirements. However, there are challenges with regard to the thermal performance of the components of the cycle. This study focuses on designing a new heat exchanger for the thermolysis reactor, which is found to be the most critical component because of having the highest operating temperature, highest exergy destruction, and material handling difficulties. The objective is to provide the required operating temperature, of 430 to 530 °C, for the …

Effects On Vehicle Ride Comfort Of An Adaptive Suspension System Using Neural Networks, Sylvia Yin Zhixian

Electronic Theses and Dissertations

Suspension systems in the auto industry have always been a topic of interest, as they relate to so many aspects of vehicles. Various types of suspension are commonly used now, such as passive suspensions, semi-active suspensions and active suspensions. However, the current technology mainly focuses on the change of damping ratio. The aim of this thesis is to consider both spring and damper properties for suspensions of an off-road vehicle. In order to do this, a 10-degree of freedom model was built using the EoM software in Julia. The output state space matrices from EoM were used as an input …

Transient Experimental Study Of A Latent Heat Thermal Energy Storage In A Phase Change Material-Air-Liquid Heat Exchanger, Serena Askar

Electronic Theses and Dissertations

The increase in energy consumption and the demand for effective thermal management systems necessitate the search for enhanced heat exchangers with high thermal performance, lower weight, and compact sizes. Crossflow heat exchangers are a key component in the thermal management system of many industries such as HVAC, automotive, etc. Generally, heat exchangers are characterized based on their steady state operating conditions. However, a transient analysis helps predict the behavior of heat exchangers when they experience variations in their operational conditions in terms of fluid flow rate and temperature.

Thermal management and thermal comfort can be achieved through active and passive …

Bake-Hardening Of Aluminum Alloys For Automotive Applications: Influence Of Temperature, Time And Pre-Strain Parameters, Giorgio Rolle

Electronic Theses and Dissertations

An experimental evaluation of the effect of bake hardening on aluminum alloys for automotive lightweight applications is developed through tensile tests and dent tests. All the alloys belong to the 6xxx series and include high formability alloys, improved hemming types and improved bake response alloys. An experimental matrix which contains different time-temperature baking conditions is built, and two pre-strain conditions are considered: no pre-strain and 2% pre-strain. A suitable testing phase is designed to be as much representative as possible of the actual manufacturing process of an automotive panel. After a data analysis phase performed by means of MATLAB software, …

Characterization Of A Three-Way Catalyst For High Efficiency Spark Ignition Engines, Cavin Hesketh

Electronic Theses and Dissertations

The push for environmental protection and sustainability has led to strict emission regulations for automotive manufacturers as evident in EURO VII and 2026 EPA requirements set to take effect in the coming years. The modern gasoline spark ignition (SI) engine typically employs various in-cylinder emission reduction techniques along with an exhaust after-treatment system to comply with emission standards. The three-way catalyst (TWC) is wholly responsible for removing the engine-out emissions including hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx). The main objective of this thesis is to investigate the impact of extensive exhaust gas recirculation (EGR) on …

Quantitative Metallurgy Of Anisotropic Nickel-Base Superalloys Under Tensile And Fatigue Loading, Dominic Devito

Electronic Theses and Dissertations, 2020-

Nickel-base superalloys are ideal materials for application in high temperature and high stress environments. Their resistance to both heat and corrosion makes these metals well-suited for use as components in engines and turbines. There has been much interest in characterizing the mechanical properties of Ni-base superalloys under severe conditions. Either large monotonic loads or cyclic loads are the most investigated. Also, research efforts tend to focus on the influence of microstructural features of fatigue life, and they accomplish this through qualitative observation. Presented here is both quantitative and qualitative analysis done on Ni-base superalloy specimens that have been subjected to …

Generative Adversarial Networks For Extrapolation Of Corrosion In Automobile Images, Andre Von Zuben

Electronic Theses and Dissertations, 2020-

Deep learning has shown success in several applications involving pattern recognition, expert systems, and scientific discovery. However, existing methods struggle with industrial applications, which are often challenged by non-ideal datasets. In many cases, the datasets are small, poorly labeled, noisy, or have unbalanced class distribution or any combination of such problems. In this Master's research, we propose a generative adversarial network (GAN) strategy that is able to circumvent limitations imposed by tiny datasets. As a case study, we use the extrapolation of corrosion in automobiles and feed our deep learning framework with only a few dozen images instead of the …

Crystal Viscoplastic Modeling Of Single Crystal And Directionally Solidified Nickel-Base Superalloys, Navindra Wijeyeratne

Electronic Theses and Dissertations, 2020-

Nickel-base superalloys (NBSAs) are widely used in engineering applications for many turbomachinery component designs. Superior material properties at high temperatures such as high tensile strength, superior fatigue strength, excellent resistance to thermal shocks, and strong corrosion resistance are primarily responsible for their extensive application. This proposal focuses on modeling generic single crystal (SX) and directionally solidified (DS) Ni-base superalloy. Compared to polycrystal superalloys, SX superalloys exhibit superior thermal fatigue and creep resistance which is attributed to the absence of grain boundaries in the SX crystalline structure. Directional solidification procedures enable the solidification structure of the materials to be comprised of …

Industry 4.0 Remanufacturing: A Novel Approach Towards Smart Remanufacturing, Prashansa Ragampeta

Masters Theses

“Smart remanufacturing has become more popular in recent years as a result of its multiple benefits and the growing need for society to encourage a circular economy that leads to sustainability. One of the most common end-of-life (EoL) choices that can lead to a circular economy is remanufacturing. As a result, at the end-of-life stage of a product, it is critical to prioritize this choice over other accessible options because it is the only recovery option that retains the same quality as a new product. This work focuses on the numerous technologies that can aid in the improvement of smart …