Mechanical Engineering Commons^™

Atmospheric Carbon Capture: A Review On Current Technologies And Analysis Of Energy Consumption For Various Direct Air Capture (Dac) Systems, Jennifer Perskin

Doctoral Dissertations and Master's Theses

Carbon dioxide (CO₂) capture is a crucial approach to reducing greenhouse gases in the atmosphere to directly combat climate change. Major components of the technology to desublimate CO₂ at cryogenic temperatures are mature and have the potential to be applied to build large Arctic/Antarctic direct-air CO₂ capture plants. Pressure swing adsorption another gas separation technique used in industry today that can be modified for atmospheric carbon capture. The discussion of energy consumption for cryogenic and combined direct air capture systems is explored in this study. The investigation of precompression of atmospheric air for a direct-air capture …

Deep Learning Of Semantic Image Labels On Hdr Imagery In A Maritime Environment, Charles Montagnoli

Doctoral Dissertations and Master's Theses

Situational awareness in the maritime environment can be extremely challenging. The maritime environment is highly dynamic and largely undefined, requiring the perception of many potential hazards in the shared maritime environment. One particular challenge is the effect of direct-sunlight exposure and specular reflection causing degradation of camera reliability. It is for this reason then, in this work, the use of High-Dynamic Range imagery for deep learning of semantic image labels is studied in a littoral environment. This study theorizes that the use HDR imagery may be extremely beneficial for the purpose of situational awareness in maritime environments due to the …

Influence Of Spray Angle And Carrier Gas Type On Micro Cold Spray Deposition Of Cu Coatings On Aln Substrates, Matthew Crocker

West Point ETD

Deposition onto conformal or angled surfaces not normal to the deposition nozzle is one of the primary impediments to implementing micro cold spray (MCS) as a film deposition technique for mass production. Increasing the ability for MCS techniques to effectively deposit on the complex geometries intrinsic to manufacturing requires understanding the effects changing deposition angles has on the film coherence, both within itself and to the substrate. In this study, deposition angle and MCS carrier gas composition are proposed and tested as variables that affect the MCS film morphology and coherence. Three gas compositions are each used to deposit MCS …

Multiscale Damage Modelling Of Notched And Un-Notched 3d Woven Composites With Randomly Distributed Manufacturing Defects, S.Z.H. Shah, Juhyeong Lee, P.S.M. Megat-Yusoff, Syed Zahid Hussain, T. Sharif, R.S. Choudhry

Mechanical and Aerospace Engineering Faculty Publications

This work proposes a stochastic multiscale computational framework for damage modelling in 3D woven composite laminates, by considering the random distribution of manufacturing-induced imperfections. The proposed method is demonstrated to be accurate, while being simple to implement and requiring modest computational resources. In this approach, a limited number of cross-sectional views obtained from micro-computed tomography (µCT) are used to obtain the stochastic distribution of two key manufacturing-induced defects, namely waviness and voids. This distribution is fed into a multiscale progressive damage model to predict the damage response of three-dimensional (3D) orthogonal woven composites. The accuracy of the proposed model was …

Steam Gasification Of Biochar To Produce Hydrogen-Rich Syngas, Nnamdi Ofuani

Honors College Theses

A key greenhouse gas (GHG) emission contributing to climate change is carbon dioxide (CO₂) emission. This emission is largely due to the use of fossil fuel as a major energy source. Biomass is an alternative energy source. Biochar, a byproduct of the pyrolysis process (of biomass), could be gasified to produce syngas (a mixture of CO and H₂). This syngas can further be used to produce different kinds of fuels like biodiesel, bio-gasoline, bioethanol, etc. In the steam gasification of biochar, the quality and yield of syngas is dependent on parameters such as temperature, particle size, …

The Future Is Now In Twisted Coil Polymer Actuators (Tcpa), Ryan Ronquillo

Electronic Theses and Dissertations

This thesis aimed to fabricate and test twisted coiled polymer actuators (TCPA) to understand the mechanical and thermal aspects of this artificial muscle fiber. The purpose of this thesis was to find a linear relationship using the LVDT sensor, fabricating TCPA fibers, and interpreting the data. The project tested whether nylon/polymer could be used as a better artificial muscle fiber.

This research accomplished three goals: (1) designing and fabricating a system capable of creating supercoiled muscle fibers consistently, (2) calibrating the Linear Variable Differential Transformer (LVDT) and Core, and (3) analyzing/interpreting the data of the Twisted Coiled Polymer Actuators (TCPA) …

Efficient Sintering Of Lunar Soil Using Concentrated Sunlight, Diprajit Biswas

Electronic Theses and Dissertations

Construction material is one crucial need for long-term habitation on the moon. When concentrated for high heat flux, solar radiation can heat lunar soil or regolith until it sinters at temperatures above 900°C. The solid, sintered soil simulant can be used as construction material. This work explores the conditions leading to effective lunar soil sintering for both direct and indirect irradiated sintering. Lunar soil simulants were sintered using concentrated light from a xenon-arc lamp with varying heat flux intensity. During direct sintering of LHS-1, a sintering range of 860°C-1140°C corresponding to a peak heat flux of 105-120 kW/m2 was identified …

Investigating The Effectiveness Of A Haptic Feedback System To Improve The Gait Speed Of Older Adults In Overground Walking, Md Tanzid Hossain

Electronic Theses and Dissertations

While the use of tactile feedback for modifying gait has recently shown promising results in a number of research studies, there has been little attention given to its ability to effect change in the gait of older adults nor has the effect of the frequency of this feedback been examined. Given the important associations of walking speed with the health of older adults, the goal of this study was to determine if a recently developed haptic feedback system could increase the walking speed of older adults and whether the frequency at which this feedback was provided would have an impact …

Mechanics And Mechanisms Of Fracture For An Eastern Spruce Subject To Transverse Loading Using Acoustic Emission, Parinaz Belalpour Dastjerdi

Electronic Theses and Dissertations

Due to its excellent structural qualities and accessibility, wood is among the most often utilized structural materials. Despite its ubiquity, wood poses numerous challenges. It is heterogeneous and anisotropic. It has a complex hierarchical ultrastructure, and the properties can have wide variation within a species, and indeed within an individual tree. This work aims to improve our understanding of the strength and fracture behavior of spruce-pine-fir (south) (SPFs), particularly in cross-grain direction. This study’s primary goal is to examine the relationship between crack propagation and cross grain morphology under the following loading configurations: compact tension, compression, and rolling shear. The …

Feasibility Of Thermoplastic Extrusion Welding As A Joining Method For Vacuum-Assisted Additively Manufactured Tooling, Chase C. Flaherty

Electronic Theses and Dissertations

In recent years, additive manufacturing (AM) has been successfully utilized for the production of large-scale composite tooling. Within these endeavors, however, limited research has focused on joining methods between printed sections. This work evaluates the feasibility of thermoplastic extrusion welding as a joining method for additively manufactured tooling structures. This joining method was assessed based on industry specifications of conventional thermoset tooling for wind blade manufacturing utilizing the vacuum-assisted resin transfer molding (VARTM) process. The specifications include requirements for the mechanical strength, vacuum integrity, roughness, and hardness of the tool surface. The feasibility of this welded polymer joint was demonstrated …

Application Of Particle Transfer By Dipping Using Polymer Binder, Md Ibrahim Khalil

Electronic Theses and Dissertations

The demand for particle transfer is increasing in various industries, such as manufacturing, metal joining, microfluidics, roller lubrication process, fuel cells, super-capacitors, hybrid coating, and protective layer applications. As a result, the importance of efficient transfer of solid micron-size particles is becoming more crucial. Submicron-sized particles can easily adhere to solid substrates due to negligible gravitational force, while micron-sized or larger particles require a binder to overcome the gravitational effects. This thesis aims to investigate the interactions between microparticles and polymer thin film on cylindrical substrates using particle transfer methods. The process parameters are optimized and demonstrated two applications of …

Investigation Into Sintered Lunar Regolith Construction Methods And Novel Usability Evaluation, Thomas A. Cox

Electronic Theses and Dissertations

Since the Apollo missions in the late 1960's, there has been a growing interest shared by many countries around the world to return to the Moon and establish a permanent Lunar settlement. The first phase of temporary Lunar bases will be established over the next several years. For a permanent human presence on the Moon, it will be necessary to use locally available resources for the construction of Lunar habitats and other infrastructure. Sintering Lunar regolith has been shown to be a promising method for producing structural material with a variety of desirable properties from strength to radiation shielding. While …

Exploring Methods For Recycling Filament Waste In 3d Printing, Max Rios Carballo

Publications and Research

The goal of the current study is to investigate cutting-edge techniques for recycling filament waste from 3D printing procedures. Appropriate waste management techniques are required to reduce this trash's harmful environmental consequences. The goal of the project is to look at new methods for recycling filament waste in order to minimize disposal and encourage reuse. To acquire data from pertinent papers and research, a thorough literature review methodology was used. The findings show that this issue may be resolved utilizing a variety of recycling techniques, including shredding, melting, and re-extrusion. The type of filament waste and the intended goal will …

A Proof-Of-Concept Study For An Elastohydrodynamic Seal Design, Cameron M. Stuart

Honors College Theses

Supercritical CO₂ (sCO₂) power cycles are superior to traditional water based, air-breathing, direct-fired, open Brayton cycles or indirect-fired, closed Rankine cycles in terms of efficiency and equipment size. They hold great potential in fossil fuel power plants, nuclear power production, solar power, geothermal power, and ship propulsion. To unlock the potential of sCO₂ power cycles, utilized technology must withstand 10–600 MWe and at sCO₂ temperatures and pressures of 350–700℃ and 20–35 MPa for nuclear industries. Amongst many challenges at the component level, the lack of suitable shaft seals for sCO₂ operating conditions needs to …

Utilization Of Machine Learning To Investigate Material State, Ana B. Abadie

Honors College Theses

The ability to predict material behavior that undergoes various loading conditions is critical to the development of reliable and safe components. Thermal and mechanical fatigue loading can cause significant damage to materials, leading to failure and potential safety hazards. Machine learning algorithms have emerged as a promising tool for improving accuracy and efficiency of predicting material behavior under such loading conditions. This research provides a comprehensive overview of a machine learning algorithm that is able to analyze and predict material state independently of the loading sequence. Unidirectional carbon fiber reinforced polymer (UD CFRP) composite which has undergone two different loading …

Multi-Mode Total Focusing Method (Mtfm) To Detect High-Temperature Hydrogen Attack (Htha) – A Review, Anjar Oktikawati, Rini Riastuti, Nursidi Yuanto

Journal of Materials Exploration and Findings (JMEF)

High temperature hydrogen attack (HTHA) is a commonly observed harm component in carbon steels exposed to high temperature and pressure in a hydrogen-rich environment. Hydrogen together with carbon responds to produce methane. The formation of methane bubbles in steel can lead to loss of fracture toughness and lead to intergranular cracking. The main challenge of this problem lies in early warning systems that can detect these bubble clusters before they reach the advanced stage. Several advanced ultrasonic inspections have been developed over the years due to the challenges of inspecting materials for defects and discontinuities. These cover time-of-flight diffraction (ToFD), …

Estimating Remaining Life And Fitness-For-Services Evaluation Of Fuel Piping Systems, Sekar Putri Purwidyasari, Ahmad Isni Kurniawan, Deni Ferdian

Journal of Materials Exploration and Findings (JMEF)

Assets life extension are required to predict the design life expiry based on condition and effects of deterioration. The remaining life assessment will answer the questions about timing of the component or equipment will lead to failure and shall be evaluated by inspection and maintenance monitoring. This study elaborates process calculation and analysis by using remaining life assessment and fitness for services method according to API 579-1/ASME FFS-1 for process piping area. The result of remaining useful life estimation and estimated life has been proposed. There are 11 piping systems based on the condition monitoring with thickness measurements. The result …

Drop Impact On Dry And Liquid Infused Substrates With Micro-Wells., Ahmed Nazrul Islam

Electronic Theses and Dissertations

Drop impact on different types of surfaces are important physical concepts that are routinely found in day-to-day life and such studies have immense application for various types of industries. One such important application of drop dynamics is in the field of aviation science which is concerned of very large freezing drizzle drops impacting on airplane wings. Such drops are known as supercooled large droplets (SLD), and they pose a great risk and have been long known to have caused notable accidents in the past. SLDs are liquid drops that can remain in the state of liquid phase and grow into …

Cycle Time Reduction In Additive Manufacturing Using Peltier Thermoelectric Cooling Devices, Trevor Carlton

Honors College Theses

Thermoelectric cooling and the Peltier effect were discovered in 1834, over 188 years ago. Additionally, the first iterations of additive manufacturing (i.e., 3D printing) began in the early 1980s, more than 40 years ago. Despite these technologies’ age and years of advancements, the application of Peltier cooling-based devices in additive manufacturing has not yet been realized. These devices can be used for the active thermal management of print beds in 3D printers. Developing a mechanism to heat and cool a print bed can reduce the cycle time to manufacture a part. In 3D printing, waiting for the heated bed to …

Study Of Different Heat Treatments And Aging Conditions For Observing Microstructures And Mechanical Properties Of Lpbf Fabricated F357 Alloy, Victor Adrian Medrano Balderas

Open Access Theses & Dissertations

Aluminum F357 is a widely used material for casting in the aerospace and additive manufacturing industry. Heat treatments are commonly applied to some aluminum alloys to modify their properties. With a further study on the aging and performance of the F357 with 3D printing technology, several industries benefit from this; military, automotive, and aerospace are some examples because of the numerous components cast in service. This work presents the mechanical properties of F357 specimens fabricated with EOS technology and subjected to heat treatments. Heat treatment conditions were applied to tensile specimens and tested. Furthermore, the specimens were subjected to artificial …