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Full-Text Articles in Engineering

Improving Future Vehicle Fuel Economy And Operational Design Domain Through Novel Data Pipelines, Kyle James Carow Apr 2023

Improving Future Vehicle Fuel Economy And Operational Design Domain Through Novel Data Pipelines, Kyle James Carow

Masters Theses

Modern automobiles have greatly advanced in recent years, with technological developments that enhance performance, safety, and comfort. However, there is still much room for improvement. Today’s vehicles are heavily reliant on the combustion of fossil fuels, proven to be harmful for the environment on both a local and global scale. In addition, the safety benefits of autonomous vehicles and advanced driver assistance systems are not yet fully realized due to the limited operational design domain of these technologies. In this research, these needs are addressed through the development of two novel data pipelines. In the first study, a novel methodology …


Large Eddy Simulation For Empirical Modeling Of The Wake Of Three Urban Air Mobility Vehicles, Denis-Gabriel Caprace, Andrew Ning Apr 2023

Large Eddy Simulation For Empirical Modeling Of The Wake Of Three Urban Air Mobility Vehicles, Denis-Gabriel Caprace, Andrew Ning

Faculty Publications

Recent advances in urban air mobility have driven the development of many new VTOL concepts. These vehicles often feature original designs departing from the conventional helicopter configuration. Due to their novelty, the characteristics of the super-vortices forming in the wake of such aircraft are unknown. However, these vortices may endanger any other vehicle evolving in their close proximity, owing to potentially large induced velocities. Therefore, improved knowledge about the wakes of VTOL vehicles is needed to guarantee safe urban air mobility operations. In this work, we study the wake of three VTOL aircraft in cruise by means of large eddy …


Droplet Capture In A Fiber Array, Karl Cardin, Christophe Josserand, Raúl Bayoán Cal Apr 2023

Droplet Capture In A Fiber Array, Karl Cardin, Christophe Josserand, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Droplets interacting with fiber arrays is ubiquitous in nature, textiles, microelectromechanical devices, and fog harvesting. The phenomena of droplet impact on an equidistant array of fibers is experimentally investigated. Drop tower tests are performed to characterize the droplet dynamics in the absence of the effects of gravity which could deform fibers and bias equilibrium configurations. Results show that contact line dissipation is largely responsible for arresting the droplet. Additionally, the penetration length is affected by fiber flexibility. A model is developed predicting the droplet penetration dynamics which shows good agreement with experiments.


Jpl Robotic Avionics & Sensor Kit (Rask), John Helzer Apr 2023

Jpl Robotic Avionics & Sensor Kit (Rask), John Helzer

Honors Program: Senior Projects (Public)

No abstract provided.


Thermal Boundary Condition Effects On Local Supercritical Co2 Heat Transfer Trends In Tubes, Nicholas C. Lopes Apr 2023

Thermal Boundary Condition Effects On Local Supercritical Co2 Heat Transfer Trends In Tubes, Nicholas C. Lopes

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide (sCO2) is a promising heat transfer fluid for the refrigeration and power generation industries due to its unique thermal properties and low environmental impact. To understand it as an alternative to traditional working fluids, the thermophysical and heat transfer phenomena of sCO2 are often studied using simplified geometries (tubes). Focus has been placed on investigating averaged heat transfer trends under an array of flow conditions with either a constant wall heat flux, constant wall temperature, or conjugate thermal boundary condition. Less emphasis has been placed on studying local sCO2 heat transfer developments. Tubular sCO2 numerical models that …


Experimental And Numerical Analysis Of A Commercial Phase Change Material Melting At Different Inclinations, Andrew Heiles Apr 2023

Experimental And Numerical Analysis Of A Commercial Phase Change Material Melting At Different Inclinations, Andrew Heiles

Doctoral Dissertations and Master's Theses

The study of various phase change materials (PCM), experimentally and numerically, have been completed over the past several years to address their feasibility and potential when used in latent heat thermal energy storage (LHTES) systems for a variety of potential applications. Previous studies have investigated changes into the type of PCM used in the system as well as the system configuration, ranging from boundary conditions to internal and external geometries and orientations of the system. The present study focused on conducting experiments at different inclination angles and isothermal wall temperatures with the organic PCM PureTemp37, and continued with a numerical …


Assessing High Dynamic Range Imagery Performance For Object Detection In Maritime Environments, Erasmo Landaeta Apr 2023

Assessing High Dynamic Range Imagery Performance For Object Detection In Maritime Environments, Erasmo Landaeta

Doctoral Dissertations and Master's Theses

The field of autonomous robotics has benefited from the implementation of convolutional neural networks in vision-based situational awareness. These strategies help identify surface obstacles and nearby vessels. This study proposes the introduction of high dynamic range cameras on autonomous surface vessels because these cameras capture images at different levels of exposure revealing more detail than fixed exposure cameras. To see if this introduction will be beneficial for autonomous vessels this research will create a dataset of labeled high dynamic range images and single exposure images, then train object detection networks with these datasets to compare the performance of these networks. …


Additive Manufacturing For Phase Change Thermal Energy Storage And Management, Thomas B. Freeman Apr 2023

Additive Manufacturing For Phase Change Thermal Energy Storage And Management, Thomas B. Freeman

Doctoral Dissertations and Master's Theses

Phase change materials can enhance the performance of energy systems by time shifting or reducing peak thermal loads. Certain electronic devices such as batteries, laser systems, or electric vehicle power electronics are highly transient and require pulse heat dissipation. Heat sinks, or thermal management devices made of a phase change material can absorb large heat spikes while maintaining a constant temperature. Additive manufacturing techniques hold tremendous potential to enable co-optimization of material properties and device geometry, while potentially reducing material waste and manufacturing time. Recently, a few efforts have emerged that employ additive manufacturing techniques to integrate a phase change …


Neural Network Fusion Of Multi-Modal Sensor Data For Autonomous Surface Vessels, David J. Thompson Apr 2023

Neural Network Fusion Of Multi-Modal Sensor Data For Autonomous Surface Vessels, David J. Thompson

Doctoral Dissertations and Master's Theses

Autonomous surface vessels (ASV) can potentially improve the safety of vessels traditionally operated by humans. Despite advancements in autonomous on-road vehicles, many of these advancements have yet to be realized for ASVs. This is primarily due to lacking ASV sensing platforms and public datasets for ASV-based perception research. To that end, this dissertation demonstrates the design of a synchronized multi-modal sensing platform for ASVs utilizing GPS/INS, LiDAR, LWIR cameras, HDR camera, and high-resolution cameras. The sensing platform is designed to maximize the overlap of sensors for multi-modal research and provides accurate intrinsic and extrinsic calibration between each sensor. Furthermore, the …


Soft Shell Helmet Cover, Jo Espiritu, Caleb Chiang, Jay Laborin, Serry Srouji, Mathew Franke Apr 2023

Soft Shell Helmet Cover, Jo Espiritu, Caleb Chiang, Jay Laborin, Serry Srouji, Mathew Franke

Mechanical Engineering Senior Theses

Lattice structures usage for attenuation is growing in popularity as 3D printing methods allow for the easier production of complex structures. The application of these impact attenuators allows for wider applications that can lead to better products in sports such as football to prevent head trauma. In this paper, we aim to design and test lattice structures to determine a lattice model that best prevents impacts through drop and compression testing to provide an outer layer of protection for football players. Initial validity through finite element analysis provided four potential lattice structures with a single parameter. Physical testing determined the …


Nautilus Rov Robot Manipulator, Dana Stefanides, Jenny Huynh, Andrew Stewart, Steven Reimer, Andrew Nguyen, Rebecca Walters, Matt Hayes Apr 2023

Nautilus Rov Robot Manipulator, Dana Stefanides, Jenny Huynh, Andrew Stewart, Steven Reimer, Andrew Nguyen, Rebecca Walters, Matt Hayes

Interdisciplinary Design Senior Theses

Global warming and climate change are prevalent issues in today’s society. As a result, research in the ocean, our world’s biggest ecosystem, is imperative in efforts to protect the environment. Santa Clara University’s Robotic Systems Lab contributes to this field through work and developments on remotely operated vehicles (ROVs). An existing ROV system called Nautilus consists of a robot arm, end effector, and storage system in order to collect various types of sediments at a depth of 300 feet. However, the previous system does not meet that requirement. In direct collaboration with researchers within the Monterey Bay Aquarium Research Institute, …


Portable Drinking Water Cooler And Dispenser, Gustavo Hernandez-Lerena, Erik Torres, Caleb Francis Parham, Terry Leung Apr 2023

Portable Drinking Water Cooler And Dispenser, Gustavo Hernandez-Lerena, Erik Torres, Caleb Francis Parham, Terry Leung

Mechanical Engineering

This document serves as the comprehensive report for the testing and building for the Portable Water-Cooling System by team AquaCool. Team AquaCool is comprised of four mechanical engineers with a passion to help the agricultural industry in their efforts to keep the health of the workers at their peak. The four engineers who partook in helping the farm workers are as follows: Caleb F. Parham, Erik Torres, Gustavo Hernandez-Lerena, and Terry Leung. To reduce the risk of heatstroke and other unwanted effects from the harsh working conditions during summer, a small and portable system was built to help in the …


Simulating Steam Jets Due To Rapid Plate Tectonics: A Computational Fluid Dynamics Analysis, Emilie Hatton Apr 2023

Simulating Steam Jets Due To Rapid Plate Tectonics: A Computational Fluid Dynamics Analysis, Emilie Hatton

Senior Honors Theses

According to the Bible's account of earth's physical history, the majority of geological change from creation to the Ice Age is a consequence of the global Flood cataclysm described in Genesis 6-8. The changes included large-scale tectonic activity, recycling all pre-Flood ocean floor into the mantle, and generating all present-day igneous ocean floor by seafloor spreading at mid-ocean rift zones. Along the middle of these zones, strips of newly formed seafloor were present near the melting temperature of basaltic magma. Above these strips of extremely hot rock, intense jets of steam would almost certainly form. This research seeks to investigate …


Robotic Arm Extrusion End Effector, Nicholas Viamin, David Blouin, Savannah Hunt, Nico Figueroa Apr 2023

Robotic Arm Extrusion End Effector, Nicholas Viamin, David Blouin, Savannah Hunt, Nico Figueroa

Interdisciplinary Design Senior Theses

This senior design project aims to enhance the capabilities of the Rotrics AIO Desktop Arm (Dexarm) by designing and implementing an extrusion device capable of smooth and consistent extrusion for 3D printing applications. The project focused on ensuring safety, affordability, and ease-of-use for users, while achieving precise control over the extrusion process. Various mechanical and electrical components were carefully selected to ensure compatibility with the Dexarm and to provide optimal performance. To maintain safety, extensive testing and risk assessments were conducted to minimize any potential hazards associated with the extrusion process. To achieve smooth and consistent extrusion, precise control mechanisms …


Spin Mediated Topological Black Hole In Acoustic Metamaterials Near Dirac-Like Cone Frequencies., Mustahseen Mobashwer Indaleeb Apr 2023

Spin Mediated Topological Black Hole In Acoustic Metamaterials Near Dirac-Like Cone Frequencies., Mustahseen Mobashwer Indaleeb

Theses and Dissertations

A unique bulk-boundary distinction and acoustic topological phenomena is discovered and explained in this dissertation. The overall objective was to discover the hidden physics, dynamic and mechanics of acoustic wave behavior that causes the formation of extremely rare ‘Topologically protected Black Hole’ (TBH) in acoustic microarchitecture metamaterials. This behavior is immensely valuable for numerous mechanical and civil engineering applications where acoustic insulators are required to create sound-free or vibration-free exterior surfaces. On the other hand, to contain the energy within the structure, for impact mitigation and energy absorption in vehicles, space crafts, aircrafts, and civil infrastructures such materials will be …


Hydrothermal Liquefaction Of Saccharina Latissima For The Production Of Biofuel, Mayokun A. Oke Apr 2023

Hydrothermal Liquefaction Of Saccharina Latissima For The Production Of Biofuel, Mayokun A. Oke

Mechanical Engineering Theses

We performed hydrothermal liquefaction of brown macroalga (Saccharina latissima) in the presence of homogenous and heterogenous catalysts such as KOH, Na2CO3, Pd/C, HZSM-5, Ce/HZSM-5, and Ni/SiO2-Al2O3 in hot compressed water, to investigate their effects on product yield and composition in the biocrude. To investigate hydrocarbon production, we used methanol as co-solvent (methanol-to-water 1/4 vol.%) and as the only liquefaction solvent. We carried out the experiments in a batch reactor at 330oC and 120-130 bar, and varying temperature, algae-to-water ratio, residence time, and pretreatment method. The biocrude yields …


Structural Integrity Assessment Of Shell And Tube Heat Exchanger Tube-To-Tubesheet Joints Fabricated Using Conventional And Nonconventional Manufacturing Processes, Dinu Thomas Thekkuden Apr 2023

Structural Integrity Assessment Of Shell And Tube Heat Exchanger Tube-To-Tubesheet Joints Fabricated Using Conventional And Nonconventional Manufacturing Processes, Dinu Thomas Thekkuden

Dissertations

Tubes and tubesheets, integral components of shell and tube heat exchangers, have an important role in the functioning of the heat transfer between the tube-side and shell-side fluids. Tube-to-tubesheet joints act as a barrier to prevent the mixing of the transfer fluids in addition to aiding the structural rigidity of the shell and tube heat exchanger. Tube expansion process and welding are the manufacturing processes used for fabricating structurally rigid tube-to-tubesheet joints. Many instances of tube-totubesheet joint failures leading to the complete collapse of the heat exchangers demand attention to assessing the mechanical and metallurgical characteristics of tube-totubesheet joints fabricated …


Flexible Materials And Applications For Wearable Sensors, Brock Ferrari Apr 2023

Flexible Materials And Applications For Wearable Sensors, Brock Ferrari

Senior Honors Theses

This literature review aimed to address the limitations of rigid wearable sensors in the medical community by investigating the development of flexible materials for remote health monitoring. A keyword search was conducted on Google Scholar, PubMed, and the Jerry Falwell Library, which yielded 9,102 articles. After applying filtering techniques, the results were narrowed down to 21 articles, which were categorized into "Present Market Conditions," "Flexible Materials for Medical Use," "Applications for Wearable Sensors," and "Potential Use Cases." Discussions were held on prominent materials such as substrate, nanocomposite, and liquid metal materials, exploring their potential applications for chemical and physical sensing, …


Development Of Mirror Flexures For Use In The Muvi Instrument, Colin W. Harrop Apr 2023

Development Of Mirror Flexures For Use In The Muvi Instrument, Colin W. Harrop

Master's Theses

The Miniaturized Ultraviolet Imager (MUVI), is a compact wide field UV imaging instrument in development at UC Berkeley Space Sciences Laboratory and Cal Poly, San Luis Obispo. MUVI is designed to fit in a 2U CubeSat form factor and provide wide field, high resolution images of the ionosphere at far ultraviolet wavelengths. This thesis details the design and analyses of MUVI’s deployable cover mirror mounting flexures. Three different flexure geometries were evaluated, an optimal candidate was determined based on a number of criteria including isolation of vibration and stress to the mirrors, manufacturability and cost. The design of the flexure …


Leveraging Automated Fiber Placement Computer Aided Process Planning Framework For Defect Validation And Dynamic Layup Strategies, Joshua Allen Halbritter Apr 2023

Leveraging Automated Fiber Placement Computer Aided Process Planning Framework For Defect Validation And Dynamic Layup Strategies, Joshua Allen Halbritter

Theses and Dissertations

Process planning represents an essential stage of the Automated Fiber Placement (AFP) workflow. It develops useful and efficient machine processes based upon the working material, composite design, and manufacturing resources. The current state of process planning requires a high degree of interaction from the process planner and could greatly benefit from increased automation. Therefore, a list of key steps and functions are created to identify the more difficult and time-consuming phases of process planning. Additionally, a set of metrics must exist by which to evaluate the effectiveness of the manufactured laminate from the machine code created during the Process Planning …


Timing Deterministic Structural Model Updating Considering Impact And Fatigue Damage, Jason Michael Smith Jr. Apr 2023

Timing Deterministic Structural Model Updating Considering Impact And Fatigue Damage, Jason Michael Smith Jr.

Theses and Dissertations

Naval ship structures such as support trusses, hull sections, driving machinery, and load-bearing beams are subjected to various damage states that develop on short-term (i.e. impact) and long-term (i.e. fatigue) timescales. Naval structures fitted with a structural health monitoring system with damage detection abilities will enable appropriate real-time adjustments to the ships’ posture and control policies and thus have increased survivability and lethality. A digital twin can provide real-time condition assessment of naval structures when conjoined with a decision-making framework will increase naval ship survivability through informed response management. A fundamental challenge for the development of digital twins is reliable …


Vision Controlled Autonomous Stakebot For Driving Stakes And Its Digital-Twin, Corey Lee Leydig Apr 2023

Vision Controlled Autonomous Stakebot For Driving Stakes And Its Digital-Twin, Corey Lee Leydig

Theses and Dissertations

In this thesis a novel vision-based AI driven autonomous ‘StakeBot’ is proposed to serve the agricultural 4.0 industries of the future. In recent years supply, demand and production of vegetables that are harvested from plants with weak stems like bell pepper, tomato, eggplant has been significantly up by several fold. With growing demand and new green-house establishments across the country production of vegetables will require a tremendous number of labors which will be hard to supply soon. To overcome the issues in addition to the labor shortages, automation through robotics will be the only viable solution. Plants like bell peppers …


An Autonomous Aerial Drone System For Water Fluorescence Mapping And Targeted Sampling, Kazi Ragib Ishraq Sanim Apr 2023

An Autonomous Aerial Drone System For Water Fluorescence Mapping And Targeted Sampling, Kazi Ragib Ishraq Sanim

Theses and Dissertations

At present, aerial drones, also known as Uncrewed Aircraft Systems (UAS) or Unmanned Aerial Vehicles (UAV), are increasingly used in time and effort-heavy scientific exploration applications. One such application is inspecting the physical, chemical, and biological state of water bodies. This thesis presents a novel autonomous system capable of sensing water properties and collecting up to three 250 mL water samples from multiple sampling locations. The system features a customized aerial drone with an in-house built fluorescence sensor and pumping mechanism. It can also map the gradient of fluorescent content across the body of water to determine the best sampling …


Nondestructive Damage Detection And Stress Corrosion Crack Mitigation In Stainless Steel Plates, Andrew Philip Campbell Apr 2023

Nondestructive Damage Detection And Stress Corrosion Crack Mitigation In Stainless Steel Plates, Andrew Philip Campbell

Theses and Dissertations

The ability to inspect and detect damage within a structure without permanent damage has broad appeal in a range of engineering applications from aerospace structures to nuclear facilities. Non-destructive evaluation (NDE) using guided ultrasonic Lamb waves has growing potential and popularity in these fields. Lamb waves are known for being sensitive to material properties and various defects across the thickness such as cracks in metallic structures and delamination or debonding in composite structures. Research has also been done on the development of fully non-contact system that generates and detects Lamb waves, particularly focused on the use of pulsed laser for …


Experimental Observation Of Sphere Symmetric Isolated Single Droplet Combustion In A Converging Channel, Mason Carrington Williams Apr 2023

Experimental Observation Of Sphere Symmetric Isolated Single Droplet Combustion In A Converging Channel, Mason Carrington Williams

Theses and Dissertations

Spherically symmetric isolated single droplet combustion has been observed mainly in microgravity conditions. This study sought to determine if spherically symmetric combustion can be produced in a lab-scale experiment using flow acceleration to counteract the effects of buoyancy. The experiment was conducted in a converging channel that decreased in width along its length to accelerate the flow and limit the formation of a boundary layer. The rate at which the area decreased was governed by the initial velocity condition set at the channel inlet.

The droplets were generated using a piezoelectric actuator which forced fuel out of an injector with …


An Artificial Intelligence Approach To Fatigue Crack Length Estimation From Acoustic Emission Signals, Shane T. Ennis Apr 2023

An Artificial Intelligence Approach To Fatigue Crack Length Estimation From Acoustic Emission Signals, Shane T. Ennis

Theses and Dissertations

As in service aircraft begin to age and fatigue, a method for evaluating the operational life they are currently operating under and have remaining comes into question. Structural health monitoring is (SHM) is a popular method of structural analysis with growing interest in the aerospace industry. SHM is capable of damage assessment and structural life estimations.

The ultimate goal of the research presented in this thesis is to develop a methodology of classifying the length of a fatigue crack though the use of machine learning. The thesis has three major chapters as described below.

The first chapter deals with the …


Comprehensive Process Planning Optimization Framework For Automated Fiber Placement, Alex Ryan Brasington Apr 2023

Comprehensive Process Planning Optimization Framework For Automated Fiber Placement, Alex Ryan Brasington

Theses and Dissertations

Advanced composite materials came about in 1966 and have since been widely used due to the possibility of superior structural performance while also achieving weight reductions. Such opportunities have led to composite materials being used to fabricate complex components, often in the aerospace sector. Most components, especially in aviation, are on a large scale and are outside the capabilities of traditional composite manufacturing techniques. Traditional manufacturing methods are also labor intensive, time consuming, have a high level of material scrap, and are prone to human error. This has led to the need for innovative manufacturing solutions to withstand the ever-increasing …


Development Of System Pressure Drop Calculation Methods For Dilute Phase Pneumatic Conveying, Ross Daniel Gorman Apr 2023

Development Of System Pressure Drop Calculation Methods For Dilute Phase Pneumatic Conveying, Ross Daniel Gorman

Theses and Dissertations

This work is focused on dilute and dense phase pneumatic conveying of bulk solids. The motivation of this work is to use industrial data to scale up existing models for pressure drop in pneumatic conveying systems, determine which models best predict pressure drop in full conveying systems, and find the empirical coefficients that go with these models.

Several major research objectives were accomplished by this work. First, system pressure drop methods were evaluated in this research. Other researchers have focused on single pipe section type pressure drops. Second, the data used in this research both for the machine learning evaluations …


Multidimensional Transport-Coupled Numerical Investigation Of Non-Premixed Low-Temperature Flame In Atmospheric And High-Pressure Systems, Sudipta Saha Apr 2023

Multidimensional Transport-Coupled Numerical Investigation Of Non-Premixed Low-Temperature Flame In Atmospheric And High-Pressure Systems, Sudipta Saha

Theses and Dissertations

Gas-phase chemical reactions coupled with multidimensional fluid flow and heat and mass transport are found in various applications, i.e., from conventional engine applications to novel combustion techniques. With the goal of understanding such complex coupling in reacting flow systems, this dissertation work focuses on developing multi-physics simulation frameworks to investigate the effect of multidimensional transport on flame dynamics. This study primarily focuses on the modeling and simulation of low temperature flame formation in i) a canonical experimental setting with counterflow burners and ii) a supercritical water medium (i.e., hydrothermal flame).

In the first part of the dissertation, simulations of the …


Adaptation Of High Spatio-Temporal Resolution Weather/Load Forecast In Real-World Distributed Energy-System Operation, Amir Ali Safaei Pirooz, Mohammad J. Sanjari, Young Jin Kim, Stuart Moore, Richard Turner, Wayne Weaver, Dipti Srinivasan, Josep M. Guerrero, Mohammad Shahidehpour Apr 2023

Adaptation Of High Spatio-Temporal Resolution Weather/Load Forecast In Real-World Distributed Energy-System Operation, Amir Ali Safaei Pirooz, Mohammad J. Sanjari, Young Jin Kim, Stuart Moore, Richard Turner, Wayne Weaver, Dipti Srinivasan, Josep M. Guerrero, Mohammad Shahidehpour

Michigan Tech Publications, Part 1

Despite significant advances in distributed renewable energy systems (DRES), the technology still faces several substantial challenges that prevent the large-scale adoption of these systems into a country’s energy sector. The intermittency of renewables, uncertainties associated with real-time multi-horizon weather and load forecasts, and lack of comprehensive control systems are among the main technical and regulatory challenges for the real-world adoption of DRES. This paper outlines the current state of knowledge in the real-world operation of DRES and also describes pathways and methodologies that enable and facilitate the uptake of DRES in a country’s energy sector.