Mechanical Engineering Commons^™

Parametric Study Of Residual Stresses In Wire And Arc Additive Manufactured Parts, Hisham Khaled Jamil Abusalma

Mechanical & Aerospace Engineering Theses & Dissertations

Wire and Arc Additive Manufacturing (WAAM) is a cost-effective additive manufacturing process due to its capability to fabricate large metal parts with high deposition rate and low equipment cost. Although this method is gaining popularity in manufacturing industry, more research is needed to understand process parameters’ effects on residual stress (RS) distribution and part distortion. As such, a 3D thermo-elastic-plastic transient model was established in ABAQUS and employed to investigate the effect of process parameters such as the torch speed, the deposition power and the interlayer dwell time on RS distribution and distortion in WAAM part. The numerical model utilized …

Sustainable Smouldering For Waste-To-Energy: Scale, Heat Losses, And Energy Efficiency, Tarek L. Rashwan

Electronic Thesis and Dissertation Repository

Applied smouldering combustion is emerging as a highly energy efficient approach towards waste-to-energy. This thesis aims to better understand this potential by addressing a critical knowledge gap between laboratory scale smouldering research and large-scale applications. Altogether, new understanding in provided on the complex and dynamic interactions between the reaction zone (smouldering front) and the cooling zone (treated inert porous media) by integrating theory, experiments, analytical modelling, and global energy balance calculations. The experiments spanned a range of reactor sizes and smouldering conditions (from weak to robust) with dry (carbon) and wet (sludge) fuels mixed in sand. This work revealed that …

Robust And Sustainable Energy Pathways To Reach Mexico’S Climate Goals, Rodrigo Mercado Fernandez

Doctoral Dissertations

As countries set climate change goals for adaptation and mitigation efforts, there are many questions regarding to how to reach these targets. These efforts will necessitate the transition of our electricity infrastructure from relying on conventional electricity generation technologies including natural gas, coal and oil, to clean energy generation with renewables. Through the three essays presented in this dissertation, we explore various pathways of development for the electricity system to reach long term climate change goals. We are interested in identifying: Is there a unique optimal development option or are there various? How do different mixes of electricity generation technologies …

Modeling Of Electrical Grid Systems To Evaluate Sustainable Electricity Generation In Pakistan, Muhammad Mustafa Amjad

Masters Theses

Pakistan has always had a history of severe energy shortfalls, which rose up to an alarming 33% in 2013. This situation was countered by investments in the energy sector through the China Pakistan Economic Corridor (CPEC), which were unfortunately largely based on brown fuels. Although beneficial in the short term, these investments do not bode well for the climate scenario of Pakistan, with various parts of the country already having experienced temperatures rise of 1-3°C. To ensure that the current situation doesn’t exacerbate and is tackled in a timely manner, this research aims to examine how the untapped potential of …

Towards A Cyber-Physical Manufacturing Cloud Through Operable Digital Twins And Virtual Production Lines, Md Rakib Shahriar

Graduate Theses and Dissertations

In last decade, the paradigm of Cyber-Physical Systems (CPS) has integrated industrial manufacturing systems with Cloud Computing technologies for Cloud Manufacturing. Up to 2015, there were many CPS-based manufacturing systems that collected real-time machining data to perform remote monitoring, prognostics and health management, and predictive maintenance. However, these CPS-integrated and network ready machines were not directly connected to the elements of Cloud Manufacturing and required human-in-the-loop. Addressing this gap, we introduced a new paradigm of Cyber-Physical Manufacturing Cloud (CPMC) that bridges a gap between physical machines and virtual space in 2017. CPMC virtualizes machine tools in cloud through web services …

Development Of Water Coning Control Design Metrics In Naturally Fractured Reservoirs, Samir Prasun

LSU Doctoral Dissertations

Naturally fractured reservoirs (NFRs) with bottom-water are known for their instant water breakthrough and severe water coning that reduces oil recovery. This is because water channels through the highly permeable fractures easily connecting the well to the aquifer bypassing the oil contained in the matrix. Remedial techniques such as producing below critical-oil rate, optimizing the well spacing and installing the downhole water sink (DWS)/ downhole water loop (DWL) technology, have already been successfully tested in single-porosity reservoirs (SPR). However, applicability of these techniques in NFRs are unknown since only a few studies have been performed on their feasibility in NFRs, …

Designing An Adjustable And Transportable Staircase, Allison Currey

Undergraduate Honors Thesis Projects

People climb stairs every day, whether it is at work, a store, or at home; however, there are populations such as people who are elderly, with pathologies, with Parkinson’s disease, or have suffered from a stroke that see climbing the stairs as a challenging task and it decreases their mobility and quality of life. Factors such as muscle weakness, strategy, and balance have been previously investigated in these populations during stair climbing. However, few studies have researched how stair climb ability, balance, and perception of difficulty are influenced by step height. The objective of this thesis is to design a …

Aerial Screw Vtol Rotorcraft, Macale Rielly, Alexa Culp, Thomas Osteen, Adeline Perry

Senior Design Project For Engineers

Known as the “Renaissance Man,” DaVinci’s impressive knowledge of mechanics and inventive prowess would influence engineers and innovators hundreds of years later to make human flight a reality. However, due to the limited capacity of engineering and manufacturing at the time, his invention had been shallowly investigated in a production setting. This project strove to properly acknowledge DaVinci’s invention by thorough examination and critical analysis of his concept with the hopes of gaining a better understanding of why it is considered the “foundation of vertical flight”.

An iterative design approach was employed, utilizing faculty and university resources, team knowledge from …

Utilization And Standardization Of Beverage Based Containers, Michael T. Bobke, Jack C. Maughan, Kenia Vargas

Industrial and Manufacturing Engineering

The purpose of this document is to formally describe and explain all of the decisions associated with the data collection and analysis for this Cal Poly Senior Project. Throughout the project, we will utilize and hone the skills that each team member has developed during our time in Cal Poly's Engineering program. In addition, this document will briefly describe some of Blue Diamond’s history as one of the biggest almond companies in the world. The statement of work will introduce and describe the current status of the beverage base container process and international beverage container design. Next it will discuss …

Rebar Impalement Safety, Spencer C. Nefores, Steven M. Hoover

Industrial and Manufacturing Engineering

This project is sponsored by Webcor with the purpose of finding a better solution to rebar impalement safety. The current rebar impalement safety caps being used by Webcor were found to frequently fall off after being installed. This results in workers being exposed to the hazard for longer than desired. The research that has been done by the team showed that rebar impalement is a serious hazard and results in injury or death every year. Site visits and interviews were performed to aid in understanding the problem and designing solutions. The customer needs, current state of the problem, existing solutions, …

Parklets San Luis, Owen Kenny, Preston Jag Stebel, Leonidas Goodman, Lukas Braun

Industrial and Manufacturing Engineering

Downtown San Luis Obispo has been a popular destination for tourists, students, families, and roadtrippers. However, according to Ryan Betz, Interim Assistant to the City Manager, foot traffic and retail business revenue has been decreasing. Downtown SLO does not have enough free public spaces. Recent projects such as sidewalk bump outs and lighted crosswalks have aimed at making SLO more pedestrian accessible, but they have not actually made downtown more pleasurable. These projects have not seemed to drive any more business or traffic downtown. There are a myriad of ways to rectify this; studies show that having a free place …

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …

Human Powered Vehicle Internal Systems Design, Zachary Broadbent, Jordan Boos, Patrick Gaertner, Caleb Miner

Williams Honors College, Honors Research Projects

The objective of this design project is to redesign the seat and steering system for the Human Powered Vehicle Team. The goal of the seat design is too improve ergonomics by making it more comfortable and adjustable. In making the seat adjustable, it will be easier for drivers to achieve an optimal efficiency when pedaling. The aim for steering will be to improve the ergonomics as well as performance by analyzing steering systems in the past and evaluating how each design was successful and for what reason. Another main goal of the steering system will be improving the stability and …

Numerical Analyses And Integration Of Split Lot Sizing Using Lean Benchmark Model For Small Lot Manufacturing In High Mix Low Volume Production, Omkar Bhosale

Theses and Dissertations--Manufacturing Systems Engineering

As the global demand for automobiles has increased rapidly over the last fifty years, customers have become more particular about the characteristics of the autos they want. This change in demand, in part has pushed manufacturing to become more flexible and created a demand for alternative, more efficient processes like the High Mix Low Volume (HMLV) production of vehicles. During HMLV, manufacturers create production lot sizes and schedule to synchronize the production processes to meet customer demand on time. The demand for the automobile parts may not be uniform or parts may not be consumed by the customer immediately, Due …

Route Planning For Long-Term Robotics Missions, Christopher Alexander Arend Tatsch

Graduate Theses, Dissertations, and Problem Reports

Many future robotic applications such as the operation in large uncertain environment depend on a more autonomous robot. The robotics long term autonomy presents challenges on how to plan and schedule goal locations across multiple days of mission duration. This is an NP-hard problem that is infeasible to solve for an optimal solution due to the large number of vertices to visit. In some cases the robot hardware constraints also adds the requirement to return to a charging station multiple times in a long term mission. The uncertainties in the robot model and environment require the robot planner to account …

Evaluation Of Control Strategies For Overhead Work Using Electromyography Of Rotator Cuff Muscles, Hossein Motabar

Graduate Theses, Dissertations, and Problem Reports

Work-related musculoskeletal disorders (MSDs) of shoulder have a significant impact on overall health and economics in the industrialized nations. Rotator cuff is the most frequently injured region in the shoulder complex. Overhead work is considered as one of the most predominant causes of rotator cuff injuries. The workers in construction, automotive, and aerospace industries are routinely exposed to overhead exertions. Elimination of overhead work is nearly impossible due to various task and technology constraints. Therefore, appropriate intervention strategies based on the engineering and administrative controls opt to be used to prevent the hazardous impact of overhead exertions. The objective of …

Solar-Powered Exploration Of The Venus Atmosphere, Marc Migliozzi, Cory Everman, Rebecca Buerhle, Umar Muhammed, Steven Abbate, Chase Champagne

Williams Honors College, Honors Research Projects

The objective of this study was to design a solar powered, unmanned aircraft to orbit in the upper Venus atmosphere and search for signs of alien life. Topics of flight conditions, signs of life, basic mission plan, source of power, design process, instrumentation, and final designs are covered. Solar energy is ideal for this type of mission because it is the only reliable and abundant energy source accessible for long term space travel. The target altitude, being 60 to 70 km, has winds of up to 95 m/s. The aircraft will need to remain stable under such conditions. Due to …

Rinse Tank Salinity Automation, George Pahoundis

Williams Honors College, Honors Research Projects

Manufacturing processes are often consisted of many different processes and sub-processes. Each of these carries its own level of importance and impact to the overall picture. In this particular sub-process, salt is rinsed from a product via a rinse tank: a tank whose salinity may not exceed a certain level and whose temperature must not fall below a certain level. This setting is a prime opportunity to implement an automated control system to allow these parameters to be met with upmost efficiency. With potential savings in excess of $20,000 per year and an estimated payback period of 8 weeks, the …

Design Of Experiments Analysis Of Powder Removal Methods For Ebm Manufactured Ti-6al-4v Parts, Luis Cesar Ramos Castañeda

Open Access Theses & Dissertations

Additive Manufacturing is a technology that allows the on-demand manufacturing of complex geometries that cannot be fabricated through traditional subtractive manufacturing methods. Powder Bed Fusion is one of the seven categories of Additive Manufacturing with two subcategories, the Laser Beam Melting and the Electron Beam Melting. Freedom of design, rapid prototyping, and customization are some of the benefits that this technology provides. Like any technology, there are limitations for each category and subcategory. The Electron Beam Melting uses the electron beam to pre-heat the powder bed, reducing the temperature difference between the build part and powder bed, causing the surrounding …