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Articles 2251 - 2280 of 30042
Full-Text Articles in Engineering
Continuing Development Of An Unmanned Vehicle For Conducting Scientific And Engineering Operations In The Littoral Zone, Peter S. Bohn
Continuing Development Of An Unmanned Vehicle For Conducting Scientific And Engineering Operations In The Littoral Zone, Peter S. Bohn
UNF Graduate Theses and Dissertations
The beach and near shore are among the most economically and environmentally important regions on earth, yet they remain poorly understood due to the challenges of surveying the surf zone and obtaining other important data during high-energy events. Traditional methods such as wading surveys, small watercraft, and specialized vehicles like the coastal research amphibious buggy (CRAB) are limited by safety risks, high mobilization costs, and restricted operating windows. The work conducted in this effort addresses these limitations by continuing development of a remotely operated vehicle (ROV) intended to be operational in harsh surf conditions to collect high-resolution bathymetric and hydrodynamic …
Identification Of Fiducial Points In Seismocardiographic Cycles Using Manual And Automated Annotation Methods, Jasmine-Vy T. Truong
Identification Of Fiducial Points In Seismocardiographic Cycles Using Manual And Automated Annotation Methods, Jasmine-Vy T. Truong
Honors Undergraduate Theses
There is currently a need for complementary methods for non-invasive cardiac monitoring. Seismocardiography (SCG), the measurement of cardiac-induced vibrations at the chest surface, has shown potential clinical utility. Improving the reliability of detecting fiducial points of electrocardiography (ECG) and SCG, which collectively capture the electro-mechanical cardiac activities, could expand ECG/SCG utility as a low-cost, accessible tool for clinical assessment. This study identifies commonly accepted criteria for fiducial point detection in SCG and ECG through an extensive literature review and signal processing techniques. The previous criteria were evaluated to identify their strengths and weaknesses. Based on the findings, an improved set …
Novel Redox Oxygen Active Materials For Solid Oxide Cells And Thermochemical Hydrogen Production, Jiaxin Lu
Novel Redox Oxygen Active Materials For Solid Oxide Cells And Thermochemical Hydrogen Production, Jiaxin Lu
Theses and Dissertations
This dissertation investigates novel materials designed to significantly enhance the performance and durability of oxygen electrodes for solid oxide cells and redox active materials for thermochemical hydrogen production. The first part of this work evaluates Ta-doped BaCoO₃₋δ (BCT) and its structural analog SrCoO₃₋δ (SCT), focusing on their catalytic performance in oxygen reduction and evolution reactions. Among BCT compositions (x = 0.1, 0.3, 0.5), the BCT10 (x = 0.1) composition exhibited the highest oxygen vacancy concentration, electronic conductivity, and lowest polarization resistance. However, SCT10 surpassed BCT10 in these critical performance parameters and also demonstrated greater stability over extended operational periods. Notably, …
From Spark To Wildfire: Predicting Wildfire Origins And The Efficacy Of “Fire Safe” Cigarettes In California Grasslands, Trevor Blackwell Haltermann
From Spark To Wildfire: Predicting Wildfire Origins And The Efficacy Of “Fire Safe” Cigarettes In California Grasslands, Trevor Blackwell Haltermann
Cal Poly Humboldt theses and projects
As wildfires in North America increase in size and frequency, the societal impacts become greater as well. With greater risk and high fire suppression costs it is pertinent to improve fire investigation methods and limit the potential for human caused ignitions. Two distinct studies were carried out to assess the accuracy of fire pattern indicators and the efficacy of “fire safe” cigarette technology in lowland grass fuel types in California. The first study utilized 24 experimental small-scale fires within a wind tunnel to examine the accuracy of microscale fire pattern indicators and the factors that influence the accuracy of predictions …
Digital Twins For Flexible Manufacturing, Drew Brandon Sander
Digital Twins For Flexible Manufacturing, Drew Brandon Sander
Theses and Dissertations
With the establishment of Digital Twins as an enabling technology for Industry 4.0, it is time to transition from the previous foundations to works that implement and highlight the capabilities Digital Twins present. The Industry 4.0 paradigm has recentered the focus on customizability, leading to reemerging goals of flexibility within manufacturing. Empowered through new cyber-physical systems, new enabling technologies are driving the revolution. To identify how Digital Twins as an enabling technology contribute to flexibility within manufacturing, a comprehensive investigation is conducted along with a detailed case study. A systematic literature review is conducted to analyze quality Digital Twin implementations …
Lunar Payload Logistics: Advancing Autonomous Control For Lunar Surface Transporter Vehicles, Liam Murray
Lunar Payload Logistics: Advancing Autonomous Control For Lunar Surface Transporter Vehicles, Liam Murray
Electronic Theses and Dissertations
No abstract provided.
Molecular Dynamics Simulations Of Key Parameters On Thermal Properties Of Carbon Nanotube Modified Epoxy Composites, Lida Najmi
Electronic Theses and Dissertations
The application of carbon nanotube (CNT)-reinforced epoxy matrix composites (CRECs) has attracted extensive attention in various industrial sectors due to the significant improvement of material properties imparted by CNTs. The thermal behavior of these nanocomposites is governed by complex heat transfer mechanisms operating at different scales, resulting in a complex relationship between the effective thermal response and the microstructural characteristics of the composite. In this study, molecular dynamics (MD) simulations were used to investigate the thermal conductivity of CRECs, focusing on the effects of key parameters such as the length and volume fraction of CNTs, the degree of cross-linking within …
Simulating Positive Ion Distribution In The Protodune Single Phase Detector, Vishnu Pfeiffer
Simulating Positive Ion Distribution In The Protodune Single Phase Detector, Vishnu Pfeiffer
Electronic Theses and Dissertations
This work covers the validation and implementation of a model to solve for argon ion (Ar+) distribution in the ProtoDUNE-SP liquid argon time projection chamber (LArTPC). ProtoDUNE-SP undergoes a constant flux of cosmic ray muons due to surface operation. The performance of the ProtoDUNE-SP provided valuable insights into single-phase technology, membrane cryostat technology, and calibration of cryogenic instrumentation. Still, challenges in achieving precise measurements persist due to the space charge effect—the distortion of the electric field within the detector due to the accumulation of positive argon ions generated from constant cosmic muon flux. The overarching goal of this thesis is …
Quantitative Assessment And Validation Of Thermal Profiles In The Protodune-Ii Horizontal Drift Detector Using Computational Fluid Dynamics, Hunter Wallster
Quantitative Assessment And Validation Of Thermal Profiles In The Protodune-Ii Horizontal Drift Detector Using Computational Fluid Dynamics, Hunter Wallster
Electronic Theses and Dissertations
The Deep Underground Neutrino Experiment (DUNE) aims to advance understanding of neutrino properties using large liquid Argon time projection chambers (LArTPCs). The ProtoDUNE-II Horizontal Drift (HD) detector, constructed at CERN in Switzerland, serves as 1:20 scale prototype to validate design and operational parameters for DUNE’s Far Detectors. Accurate prediction of cryostat thermal behavior is critical to predicting liquid Argon purity distributions and detector performance, motivating the development of a validated computational fluid dynamics (CFD) model. This research extends previous work at South Dakota State University by constructing a higher-fidelity CFD simulation of ProtoDUNE-II HD using Siemens Simcenter StarCCM+® 19.04.007. Geometry …
Mid-Scale Rover Gravity Offloader (Mrgo): Design, Implementation, And Experimental Validation, Alexander Schaar
Mid-Scale Rover Gravity Offloader (Mrgo): Design, Implementation, And Experimental Validation, Alexander Schaar
Electronic Theses and Dissertations
This thesis presents the design, implementation, and validation of the Mid Scale Rover Gravity Offloader (MRGO), a terrestrial testbed developed to simulate partial-gravity conditions for planetary rover testing within a three-dimensional environment. The MRGO enables consistent, user-defined offloading force as a rover drives freely within a 20 by 18 ft test area, while a stepper motor rail gantry autonomously tracks the rover’s motion and maintains overhead alignment. Mounted to the moving gantry is a vertical carriage column that houses the offloading mechanism, which accommodates up to 5 ft of vertical displacement without loss of force accuracy. This configuration allows realistic …
Advances In Battery Modeling And Management Systems: A Comprehensive Review Of Techniques, Challenges, And Future Perspectives, Seyed Saeed Madani, Yasmin Shabeer, Ananthu Shibu Nair, Michael Fowler, Satyam Panchal, Carlos Ziebert, Hicham Chaoui, Shi Xue Dou, Khay See, Saad Mekhilef, Françios Allard
Advances In Battery Modeling And Management Systems: A Comprehensive Review Of Techniques, Challenges, And Future Perspectives, Seyed Saeed Madani, Yasmin Shabeer, Ananthu Shibu Nair, Michael Fowler, Satyam Panchal, Carlos Ziebert, Hicham Chaoui, Shi Xue Dou, Khay See, Saad Mekhilef, Françios Allard
Electrical & Computer Engineering Faculty Publications
Energy storage systems (ESSs) and electric vehicle (EV) batteries depend on battery management systems (BMSs) for their longevity, safety, and effectiveness. Battery modeling is crucial to the operation of BMSs, as it enhances temperature control, fault detection, and state estimation, thereby maximizing efficiency and preventing malfunctions. This paper thoroughly examines the most recent advancements in battery and BMS modeling, including data-driven, thermal, and electrochemical methods. Advanced modeling approaches are explored, including physics-based models that incorporate mechanical stress and aging effects, as well as artificial intelligence (AI)-driven state estimation. New technologies that facilitate data-driven decision-making, real-time monitoring, and simplified systems include …
A Novel Intelligent Thermal Feedback Framework For Electric Motor Protection In Embedded Robotic Systems, Mohamed Shili, Salah Hammedi, Hicham Chaoui, Khaled Nouri
A Novel Intelligent Thermal Feedback Framework For Electric Motor Protection In Embedded Robotic Systems, Mohamed Shili, Salah Hammedi, Hicham Chaoui, Khaled Nouri
Electrical & Computer Engineering Faculty Publications
As robotic systems advance in autonomy and sophistication while being used in uncertain environments, the challenge of building reliable and robust electric motors that are embedded into robotic systems has never been a more important engineering problem. Thermal distress caused by extended operation or excessive loading can negatively affect a motor’s performance and efficiency and lead to catastrophic hardware failure. This paper proposes a novel intelligent control framework that includes real-time thermal feedback for hybrid electric motors that are embedded into robotic systems. The framework relies on adaptive control techniques and lightweight machine learning techniques to estimate internal motor temperatures …
Biomechanics Of Teeth Alignment Using Clear Aligners With Various Attachment Shapes And Orientations, Egon Mamboleo
Biomechanics Of Teeth Alignment Using Clear Aligners With Various Attachment Shapes And Orientations, Egon Mamboleo
Graduate Theses, Dissertations, and Problem Reports (ETD)
Clear aligners have emerged as the most popular and preferred method of treatment for patients with orthodontic malocclusions. This is greatly due to the comfort and aesthetically appealing factors when compared to fixed appliances . Clear aligners are either thermoformed or 3D direct-printed plastics that apply biomechanical forces to the surface of teeth to trigger tooth movement and bone remodeling process. Common Class I malocclusions with mild or moderate crowding can be treated with clear aligners alone. However, treatment of Class II and Class III malocclusions that require extraction of permanent teeth or correction of severe rotations, and teeth extrusions …
Framework For Development Environment Selection In Digital Twin Applications, Carlos Dodero Fernandez
Framework For Development Environment Selection In Digital Twin Applications, Carlos Dodero Fernandez
Graduate Theses, Dissertations, and Problem Reports (ETD)
Digital Twin (DT) technology, a cornerstone of Industry 4.0, facilitates real-time synchronization between virtual models and physical manufacturing systems, enhancing operational efficiency and decision-making. However, its widespread adoption is hindered by the absence of standardized methods for selecting Development Environments (DEs) for DTs, compounded by challenges in cost, interoperability, and connectivity with Industrial Internet of Things (IIoT) protocols. This thesis proposes a Systematic Selection Framework to address this gap, offering a structured methodology to evaluate DEs based-on visualization quality, scalability, interoperability, and cost-effectiveness for manufacturing applications. The framework categorizes and compares sixteen DEs into Game Engines, Robotics Engines, and Simulation …
A Generalized Coherence Framework For Quantifying Input Contributions In Multi-Input Systems With Correlated Or Uncorrelated Inputs, Nolan H. Howes, Matthew S. Allen, Dario Farina, Steven Knight Charles
A Generalized Coherence Framework For Quantifying Input Contributions In Multi-Input Systems With Correlated Or Uncorrelated Inputs, Nolan H. Howes, Matthew S. Allen, Dario Farina, Steven Knight Charles
Faculty Publications
In multi-input systems, it is often necessary to quantify the contribution of each input to an output. Such contribution analysis is frequently performed using coherence. However, when correlation is present between inputs, existing coherence measures do not accurately quantify the contribution of individual inputs, except in special cases. Here we propose an expanded coherence framework that enables contribution analysis in any multi-input system, regardless of input correlation. We bridged the gap by defining three new coherence measures: component, excluded, and isolated coherence. Component coherence is an intermediate measure that decomposes measured output power into components attributable to inputs directly vs …
Comparing The Sensitivity And Specificity Of Novel Motor Assessments For Traumatic Brain Injury, Paula K. Johnson, Ariana M. Hedges-Muncy, Erin D. Bigler, Lorie Richards, Steven Knight Charles
Comparing The Sensitivity And Specificity Of Novel Motor Assessments For Traumatic Brain Injury, Paula K. Johnson, Ariana M. Hedges-Muncy, Erin D. Bigler, Lorie Richards, Steven Knight Charles
Faculty Publications
Background: Portable technology that records movements with high accuracy provides potential for sensitive clinical movement tests for individuals who experienced a traumatic brain injury (TBI). Objective: (1)To present impairments assessed using markerless motion capture (MMC) and (2) to compare the sensitivity and specificity of the MMCmediated tests to each other and to common clinical tests. Design: Screening study, using as criterion standard the ability to classify participant with TBI versus control participant. Setting: Research laboratory. Participants: The study included 30 individuals with TBI and 101 control participants. Entry criteria included most recent head injury < 5 years old, no history of movement issues prior to injury, no movement-affecting medications, and sufficient cognitive ability to follow instructions. Interventions: Not applicable. Main Outcome Measures: Performance on MMC-mediated tests and existing clinical analogs. MMC-mediated tests included finger oscillation, simple reaction time, and visually guided movement tasks. For comparison, participants also completed the following clinical tests: Halstead–Reitan finger tapping, simple reaction time test, and Beery Visuomotor Integration test. Impairments were identified as test scores of participants with TBI that fell outside of the 95% interval of control participants’ test scores. Random forest analysis was used to calculate the sensitivity and specificity of MMC and clinical tests according to their ability to correctly classify participants with TBI and control participants. Results: MMC-mediated tests revealed impairments in more participants with TBI than clinical tests in all three TBI groups (mild, repeated, and moderate to severe). Similarly, MMC-mediated tests revealed a higher percentage of scores as impairments than clinical tests in all three groups with TBI. Furthermore, MMC-mediated tests proved more sensitive and more specific than clinical tests (70% versus 50% and 98% versus 93%, respectively). Conclusion: MMC-mediated tests are sensitive and specific (compared to traditional clinical tests) and have potential to fill a gap in clinical care of TBI.
A Framework For Biomimetic Robot Design Applied To The Development Of A Robotic Model Of Drosophila Melanogaster, Clarissa A. Goldsmith
A Framework For Biomimetic Robot Design Applied To The Development Of A Robotic Model Of Drosophila Melanogaster, Clarissa A. Goldsmith
Graduate Theses, Dissertations, and Problem Reports (ETD)
For decades, the field of biologically inspired robotics has leveraged insights from animal locomotion to improve the walking ability of legged robots. Recently, “biomimetic” robots have been developed to model how specific animals walk. By prioritizing biological accuracy to the target organism rather than the application of general principles from biology, these robots can be used to develop detailed biological hypotheses for animal experiments, ultimately improving our understanding of the biological control of legs while improving technical solutions. Much of this work involves biologically inspired walking controllers informed by the morphology and dynamics of the insect nervous system, which necessitate …
Microwave-Assisted Reduction Of Critical Metal Oxides From E-Waste Mixture, Kurundu Shavinka Jayasekera
Microwave-Assisted Reduction Of Critical Metal Oxides From E-Waste Mixture, Kurundu Shavinka Jayasekera
Graduate Theses, Dissertations, and Problem Reports (ETD)
The efficient recovery of critical metals such as tantalum (Ta), manganese (Mn), gallium (Ga), and indium (In) from electronic waste (e-waste) is essential for resource sustainability and environmental protection. This research uses microwave-assisted treatment to investigate the carbothermal reduction of these four specific metals from their oxides in a simulated e-waste mixture, with carbon black serving as both a microwave coupling and reduction agent. Microwave processing is used specifically because it offers a rapid and energy-efficient alternative to conventional thermal methods, with the benefits of intrinsic heating and selective heating of materials. The first experiments centered on understanding the effects …
La2nio4+Δ-Based Solid Oxide Electrolysis Cell (Soecs) Electrodes Enhanced With Complex Perovskite Nanocatalyst Processed By Surfactant-Enabled Infiltration, Cole Samuel Klemstine
La2nio4+Δ-Based Solid Oxide Electrolysis Cell (Soecs) Electrodes Enhanced With Complex Perovskite Nanocatalyst Processed By Surfactant-Enabled Infiltration, Cole Samuel Klemstine
Graduate Theses, Dissertations, and Problem Reports (ETD)
As the world seeks to reduce its reliance on hydrocarbons, the demand for sustainable hydrogen production methods has become increasingly critical. Hydrogen is a versatile energy carrier that can be produced from various sources, including water, natural gas, and biomass. Replacing the burning of hydrocarbons with hydrogen could significantly reduce greenhouse gas emissions, contributing to global climate goals like those set by the US H2NEW program. The joint technologies of solid oxide fuel and electrolysis cells present the ability to both produce and process clean hydrogen to meet these goals. Development into solid oxide fuel cells has been met with …
Finite Element Modeling And Experimental Characterization Of Overmolded Gold-Palladium Composite Leads And Their Mechanical Behavior Under Cyclic Fatigue For Long-Term Implant Applications, Tanner Davis
Graduate Theses, Dissertations, and Problem Reports (ETD)
Auditory Nerve Interface (ANI) devices, currently in developmental stages, represent an emerging neuroprosthetic approach to restore hearing in severe sensorineural loss patients by directly stimulating the auditory nerve via the Utah Slanted Electrode Array (USEA). Conventional implant leads are comprised of multiple wires made from materials such as platinum-iridium and MP35N stainless steel that are overmolded in an insulative material. These materials are not possible to bond with to electrode array used in the ANI device, necessitating the evaluation of a new material like Au-Pd to ensure its functionality and durability under cyclic stresses. This gap necessitates characterization of alternative …
Reactive Model-Free Control For Underactuated Vehicles Operating In Resource-Constrained Environments, Austin Lane Sponaugle
Reactive Model-Free Control For Underactuated Vehicles Operating In Resource-Constrained Environments, Austin Lane Sponaugle
Graduate Theses, Dissertations, and Problem Reports (ETD)
Buoyancy-driven, underactuated vehicles offer a compelling solution for long-duration autonomous operations in constrained environments. By leveraging buoyancy to generate lift, these vehicles can remain aloft for extended periods with minimal power requirements, making them well-suited for applications in atmospheric monitoring, planetary exploration, and communications. However, their limited actuation authority, strong coupling with environmental forces, and operating domains introduce significant control challenges, including nonlinearity, sensitivity to external disturbances, and limited observability.
This work investigates the design and implementation of lightweight, reactive model-free control strategies that enable robust autonomy in such constrained settings. A digital Extremum Seeking Controller (ESC) is first implemented …
Assessing And Predicting The Impact Of A Retrofitted Methane Mitigator On Non-Road Large Natural Gas Engines Using Artificial Neural Networks, Augustine Thomas Ojo
Assessing And Predicting The Impact Of A Retrofitted Methane Mitigator On Non-Road Large Natural Gas Engines Using Artificial Neural Networks, Augustine Thomas Ojo
Graduate Theses, Dissertations, and Problem Reports (ETD)
Abstract
ASSESSING AND PREDICTING THE IMPACT OF A RETROFITTED METHANE MITIGATOR ON NON-ROAD LARGE NATURAL GAS ENGINES USING ARTIFICIAL NEURAL NETWORKS
Augustine Thomas Ojo
Methane emissions from the oil and gas sector present a pressing environmental and economic challenge, given methane’s high global warming potential and the considerable volumes of unutilized gas lost from industrial processes. This study investigates the impact of a retrofitted methane mitigation system, the Methane Mitigator (M²), on fuel consumption and engine-out emissions in non-road, four-stroke natural gas-powered, lean-burn engines and develops predictive Artificial Neural Network (ANN) models to estimate the resulting engine-out emissions and fuel …
Dynamic Force Feedback Controller Improves Metrics Of Stepping In A Biomimetic Robot Leg, Isabella Mae Kudyba
Dynamic Force Feedback Controller Improves Metrics Of Stepping In A Biomimetic Robot Leg, Isabella Mae Kudyba
Graduate Theses, Dissertations, and Problem Reports (ETD)
Force feedback is a type of robotic control where forces are measured, fed back into the control system, and actuation is adjusted to compensate for environmental forces, with the goal of quick and precise limb positioning in walking. Robots of today use single force sensors (e.g. pressure sensitive pads, load cells) per leg which are often bulky, expensive, and susceptible to crosstalk. Walking robots often employ model predictive controllers or policy controllers trained through reinforcement learning (RL) to actuate their limbs, but these methods are time and energy consuming. Biomimetic robots offer an alternative approach, investigating biological theories with the …
Fundamental And Applied Investigation Of Ammonia Combustion: Characteristics And Emissions At Relevant Ic Engine Conditions, Luis Fernando Alvarez Correa
Fundamental And Applied Investigation Of Ammonia Combustion: Characteristics And Emissions At Relevant Ic Engine Conditions, Luis Fernando Alvarez Correa
Graduate Theses, Dissertations, and Problem Reports (ETD)
Ammonia (NH3) is regarded as a promising fuel for future carbon-free power and propulsion systems due to its high hydrogen content, ease of storage, and existing infrastructure. Despite these advantages, NH3 exhibits inherently poor combustion characteristics, including low laminar burning velocity, high ignition energy, narrow flammability limits, and sluggish chemical kinetics. These limitations were solved in prior research by blending NH3 with hydrogen (H2) or hydrocarbons, which improved reactivity but introduced trade-offs such as increased complexity, safety concerns, or carbon emissions. Consequently, there remains a significant lack of fundamental and applied research on neat NH3 combustion, particularly under engine-relevant conditions …
Characterization Of Properties And Defects Of Alternative Matrix Materials For 3d Printed Continuous Carbon Fiber Reinforced Composites, Noah Darren Osborne
Characterization Of Properties And Defects Of Alternative Matrix Materials For 3d Printed Continuous Carbon Fiber Reinforced Composites, Noah Darren Osborne
Graduate Theses, Dissertations, and Problem Reports (ETD)
Additive manufacturing, commonly known as 3D printing, has the potential to transform the production of end-use parts by facilitating the creation of complex shaped, low-volume components that are expensive to manufacture using traditional methods. However, thermoplastic polymer matrices currently utilized in 3D printing of carbon fiber composites, often lack the mechanical properties needed for aerospace applications. To address this issue, researchers have developed fiber-reinforced 3D-printed composites using an innovative two-step process which involves printing 3D preforms using fused deposition modeling, followed by compression molding. However, most previous work involves the use of nylon-based polymer matrices while there are a number …
Development Of A Model To Estimate Engine Crankcase Methane Vent Emission Rates, Juan Pablo Rincon
Development Of A Model To Estimate Engine Crankcase Methane Vent Emission Rates, Juan Pablo Rincon
Graduate Theses, Dissertations, and Problem Reports (ETD)
The primary focus of this research is the modeling and validation of crankcase methane emissions stemming from natural gas combustion engines commonly deployed in the natural gas compression industry. The models employed rely on equations predicting the flow rate and composition of losses, typically generated within reciprocating piston-cylinder systems. Since crankcase emissions originate in a piston–cylinder arrangement, multiple variables were considered in this study, including displaced volume, pressure, temperature, flow, and viscosity (with corrections applied to account for the thermal and compositional effects on the mixture of fluids). The initial data for this research was collected during three measurement campaigns …
Actuator Disk Model For Aeropropulsive Coupling Effects In Vortex Particle Method, Eduardo Alvarez, Vineet Ahuja, Vinod Lakshminarayan, Aaron Perry, Ryan Anderson, Andrew Ning
Actuator Disk Model For Aeropropulsive Coupling Effects In Vortex Particle Method, Eduardo Alvarez, Vineet Ahuja, Vinod Lakshminarayan, Aaron Perry, Ryan Anderson, Andrew Ning
Faculty Publications
Blown lift and distributed electric propulsion aircraft pose strong aeropropulsive coupling effects that cannot be ignored during the early stages of design. In this study, we develop an advanced actuator disk model (ADM) for aeropropulsive coupling effects of ducted fans with the vortex particle method (VPM). The advanced ADM consists of (1) an actuator disk at the rotor plane, (2) a surface vortex sheet modeling the mixing and convection of blade tip vorticity along walls, and (3) a powered wake at the exhaust. With these three components, a propulsion jet with an arbitrary velocity profile is formed and interactions with …
Mill Power Consumption And Fuel Particle Size Distribution While Co-Milling Bituminous Coal With Steam-Exploded Woody Biomass In A Conventional Bowl Mill, Brian Schoof, Rajarshi Roy, Regan Kuttler, Parker Latour, Scott Montgomery, Jacob Tuttle, Gwendolyn Bennett Bennett, Brian D. Iverson, Andrew Fry
Mill Power Consumption And Fuel Particle Size Distribution While Co-Milling Bituminous Coal With Steam-Exploded Woody Biomass In A Conventional Bowl Mill, Brian Schoof, Rajarshi Roy, Regan Kuttler, Parker Latour, Scott Montgomery, Jacob Tuttle, Gwendolyn Bennett Bennett, Brian D. Iverson, Andrew Fry
Faculty Publications
The mill behavior of a 312 Combustion Engineering Raymond Bowl Mill was studied with five blends of Utah bituminous coal and steam-exploded woody biomass, ranging from 100 % coal to 100 % biomass. Mill power consumption increased with biomass content, peaking at 187 % of the power required for 100 % coal before the mill faulted at 100 % biomass. After repositioning the rollers, power consumption for 100 % biomass decreased by 13 % compared to 100 % coal. SEM images revealed that milled biomass particles were non-spherical, indicating some fibrous structure remained post steam-explosion. The particle size distribution (PSD) …
Drop Dynamics During Condensation On Superhydrophobic Surfaces In Vapor Shear Flow, Shaur Humayun, R. Daniel Maynes, Julie Crockett, Brian D. Iverson
Drop Dynamics During Condensation On Superhydrophobic Surfaces In Vapor Shear Flow, Shaur Humayun, R. Daniel Maynes, Julie Crockett, Brian D. Iverson
Faculty Publications
Accurate models for predicting drop dynamics, such as maximum drop departure sizes, are crucial for estimating heat transfer rates during condensation on superhydrophobic (SH) surfaces. Previous studies have focused on examining the heat transfer rates for SH surfaces under the influence of gravity or vapor flowing over the surface. This study investigates the impact of surface solid fraction and texture scale on drop mobility in a condensing environment with a humid air flow. Experiments recorded condensation with varying surface feature sizes from micro- to nano scale under different flow rates. Video analysis detected the drop-size distribution and maximum drop departure …
Development And Deployment Of In Situ Fiber Optic Distributed Temperature Sensing Systems And Data Processing Workflows For Oceanographic Observatories In Coastal And Deep-Sea Environments, Johann Sebastian Becker
Development And Deployment Of In Situ Fiber Optic Distributed Temperature Sensing Systems And Data Processing Workflows For Oceanographic Observatories In Coastal And Deep-Sea Environments, Johann Sebastian Becker
Open Access Dissertations
Over the last two decades, fiber optic distributed temperature sensing (DTS) has emerged as a transformative technology capable of providing unprecedented spatiotemporal resolution observations of temperature in a broad range of environmental sensing, industrial, and civil engineering monitoring applications. DTS uses a single interrogator unit to measure temperature continuously along an optical fiber, effectively turning the fiber into the equivalent of an array of temperature probes that can be interrogated synoptically. Modern commercially-available DTS systems are capable of continuous sensing with sampling frequencies up 5 sec, spatial resolution of 0.25 m, and temperature precision up to 0.01 °C) observations, on …