Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 215

Full-Text Articles in Engineering

Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto Mar 2024

Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto

Publications

Highly diverse agroecosystems are increasingly of interest as the realization of farms’ invaluable ecosystem services grows. Simultaneously there has been an increased use of uncrewed aerial systems (UAS) in remote sensing as drones offer a finer spatial resolution and faster revisit rate than traditional satellites. With the combined utility of UAS and the attention on agroecosystems, there exists an opportunity to assess UAS practicality in highly biodiverse settings. In this study, we utilized UAS to collect fine-resolution 10-band multispectral imagery of coffee agroecosystems in Puerto Rico. We created land cover maps through a pixel-based supervised classification of each farm and …


Immersive Framework For Designing Trajectories Using Augmented Reality, Joseph Anderson, Leo Materne, Karis Cooks, Michelle Aros, Jaia Huggins, Jesika Geliga-Torres, Kamden Kuykendall, David Canales, Barbara Chaparro Jan 2024

Immersive Framework For Designing Trajectories Using Augmented Reality, Joseph Anderson, Leo Materne, Karis Cooks, Michelle Aros, Jaia Huggins, Jesika Geliga-Torres, Kamden Kuykendall, David Canales, Barbara Chaparro

Publications

The intuitive interaction capabilities of augmented reality make it ideal for solving complex 3D problems that require complex spatial representations, which is key for astrodynamics and space mission planning. By implementing common and complex orbital mechanics algorithms in augmented reality, a hands-on method for designing orbit solutions and spacecraft missions is created. This effort explores the aforementioned implementation with the Microsoft Hololens 2 as well as its applications in industry and academia. Furthermore, a human-centered design process and study are utilized to ensure the tool is user-friendly while maintaining accuracy and applicability to higher-fidelity problems.


Experimental Analysis Of The Integrated High-Lift Propulsor, Robert W. Deters, Byron Ward, Shreyas Narsipur Jan 2024

Experimental Analysis Of The Integrated High-Lift Propulsor, Robert W. Deters, Byron Ward, Shreyas Narsipur

Publications

Wind tunnel testing was conducted to evaluate the performance of the Integrated High Lift Propulsor (IHLP), a novel Distributed Electric Propulsion (DEP) system. The IHLP integrates traditional Krueger flap/slat elements with a Distributed Electric Propulsion design, enhancing high lift performance and cruise efficiency compared to conventional pylon-mounted DEP configurations. Starting from a baseline configuration determined from pretest Computational Fluid Dynamics (CFD) analyses, a parametric study was performed to determine the influence on the aerodynamic characteristics (𝐶𝑙 , 𝐶𝑥, and 𝐶𝑚). The study involved variations in flap settings, slat angles, overlap, propeller tilt, and propeller position. The impact of Reynolds number, …


On Progress In Exploring Controlled Viscous Limit-Cycle Oscillations In Modified Glauert Airfoil, Ethan Deweese, Lap Nguyen, Erik Vataker, William Mackunis, Vladimir Golubev, Ron Efrati, Oksana Stalnov Jan 2024

On Progress In Exploring Controlled Viscous Limit-Cycle Oscillations In Modified Glauert Airfoil, Ethan Deweese, Lap Nguyen, Erik Vataker, William Mackunis, Vladimir Golubev, Ron Efrati, Oksana Stalnov

Publications

The paper reports on the progress in the development of a novel robust, nonlinear flow control technology that employs an array of synthetic-jet actuators (SJAs) embedded in 2-DOF, elastically mounted, optimized Modified Glauert (MG) airfoil design in order to control limit cycle oscillations (LCO) at low subsonic flow regimes. The focus here is on the conceptual design of the wind energy harvesting system that employs, e.g., a piezoelectric device to extract energy from plunging LCO, with the closed-loop controller being capable to sustain the required LCO amplitudes over a wide range of wind speeds. The current high-fidelity studies first include …


Experimental Environmental Profiles And Sloshing Dynamics Aboard Zero-G Aircraft, Pedro J. Llanos, Sathya Gangadharan, Kevin Crosby Jan 2024

Experimental Environmental Profiles And Sloshing Dynamics Aboard Zero-G Aircraft, Pedro J. Llanos, Sathya Gangadharan, Kevin Crosby

Publications

This study presents the results of a parabolic flight experiment to study the sloshing dynamics of the magneto-active propellant management device experiment. This device utilizes a magnetoactive membrane and magnets located external to the tank to effectively damp the liquid free surface motion. This research work establishes a benchmark with sloshing analytical formulation and sensor calibration methods that can be used to characterize future research parabolic flights while providing important environmental profiles measured during flight, such as accelerations, pitch angle, velocity, temperature, total volatile content, carbon dioxide, relative humidity, magnetic field, and radiation. Correlation between these flight variables and the …


Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik Dec 2023

Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik

Publications

A reinforced carbon composite can include a carbon sub­strate and a metal organic framework bonded to the carbon substrate. For example, a reinforced carbon composite can include a first layer, a second layer, and a resin adhered to the first layer and the second layer. The first layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate. The second layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate.


Six-Degree-Of-Freedom Optimal Feedback Control Of Pinpoint Landing Using Deep Neural Networks, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua Nov 2023

Six-Degree-Of-Freedom Optimal Feedback Control Of Pinpoint Landing Using Deep Neural Networks, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua

Student Works

Machine learning regression techniques have shown success at feedback control to perform near-optimal pinpoint landings for low fidelity formulations (e.g. 3 degree-of-freedom). Trajectories from these low-fidelity landing formulations have been used in imitation learning techniques to train deep neural network policies to replicate these optimal landings in closed loop. This study details the development of a near-optimal, neural network feedback controller for a 6 degree-of-freedom pinpoint landing system. To model disturbances, the problem is cast as either a multi-phase optimal control problem or a triple single-phase optimal control problem to generate examples of optimal control through the presence of disturbances. …


Orbital Debris Mitigation: Exploring Cubesat Drag Sail Technology, Robinson Raphael Oct 2023

Orbital Debris Mitigation: Exploring Cubesat Drag Sail Technology, Robinson Raphael

Student Works

In an era marked by remarkable advancements in space exploration and research, the advent of satellite technology has contributed accordingly to the lives of people here on Earth. Through applications that tie into broadband connectivity, weather forecasting, disaster management, etc., the occupancy in orbital domains like Low-Earth Orbit (LEO) only continues to grow. However, the presence of orbital debris emerges as a significant concern, posing threats to both operational satellites and future space missions. Resulting as a consequence due to decades of activities since the launch of Sputnik 1 in 1957, as more countries ventured into space so did the …


State Space Modeling And Estimation Of Flexible Structure Using The Theory Of Functional Connections, Carlo Lombardi, Riccardo Bevilacqua Oct 2023

State Space Modeling And Estimation Of Flexible Structure Using The Theory Of Functional Connections, Carlo Lombardi, Riccardo Bevilacqua

Student Works

In this work, we present a novel method to model the dynamics of a continuous structure based on measurements taken at discrete points. The method is conceived to provide new instruments to address the problem of flexible dynamics modeling in a spacecraft, where an effective mathematical representation of the non-rigid behavior of the is of critical importance in the design of an effective and reliable attitude estimation and control system. Both the measurements and the model that describes the structure can be affected by uncertainty. The purpose of the developed method is to estimate the position and the velocity of …


Using Machine Learning To Predict Hypervelocity Fragment Propagation Of Space Debris Collisions, Katharine Larsen, Riccardo Bevilacqua Oct 2023

Using Machine Learning To Predict Hypervelocity Fragment Propagation Of Space Debris Collisions, Katharine Larsen, Riccardo Bevilacqua

Student Works

The future of spaceflight is threatened by the increasing amount of space debris, especially in the near-Earth environment. To continue operations, accurate characterization of hypervelocity fragment propagation following collisions and explosions is imperative. While large debris particles can be tracked by current methods, small particles are often missed. This paper presents a method to estimate fragment fly-out properties, such as fragment, velocity, and mass distributions, using machine learning. Previous work was performed on terrestrial data and associated simulations representing space debris collisions. The fragmentation of high-velocity fragmentation can be modeled by terrestrial fragmentation tests, such as static detonations. Recently, stereoscopic …


Stability Of Deep Neural Networks For Feedback-Optimal Pinpoint Landings, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua Oct 2023

Stability Of Deep Neural Networks For Feedback-Optimal Pinpoint Landings, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua

Student Works

The ability to certify systems driven by neural networks is crucial for future rollouts of machine learning technologies in aerospace applications. In this study, the neural networks are used to represent a fuel-optimal feedback controller for two different 3-degree-of-freedom pinpoint landing problems. It is shown that the standard sum-ofsquares Lyapunov candidate is too restrictive to assess the stability of systems with fuel-optimal control profiles. Instead, a parametric Lyapunov candidate (i.e. a neural network) can be trained to sufficiently evaluate the closed-loop stability of fuel-optimal control profiles. Then, a stability-constrained imitation learning method is applied, which simultaneously trains a neural network …


Predicting Dynamic Fragmentation Characteristics From High-Impact Energy Events Utilizing Terrestrial Static Arena Test Data And Machine Learning, Katharine Larsen, Riccardo Bevilacqua, Omkar S. Mulekar, Elisabetta L. Jerome, Thomas J. Hatch-Aguilar Aug 2023

Predicting Dynamic Fragmentation Characteristics From High-Impact Energy Events Utilizing Terrestrial Static Arena Test Data And Machine Learning, Katharine Larsen, Riccardo Bevilacqua, Omkar S. Mulekar, Elisabetta L. Jerome, Thomas J. Hatch-Aguilar

Student Works

To continue space operations with the increasing space debris, accurate characterization of fragment fly-out properties from hypervelocity impacts is essential. However, with limited realistic experimentation and the need for data, available static arena test data, collected utilizing a novel stereoscopic imaging technique, is the primary dataset for this paper. This research leverages machine learning methodologies to predict fragmentation characteristics using combined data from this imaging technique and simulations, produced considering dynamic impact conditions. Gaussian mixture models (GMMs), fit via expectation maximization (EM), are used to model fragment track intersections on a defined surface of intersection. After modeling the fragment distributions, …


Adaptive Modified Rise-Based Quadrotor Trajectory Tracking With Actuator Uncertainty Compensation, Emmanuel Ogbanje Ijoga, William Mackunis, Krishna Bhavithavya Kidambi, Madhur Tiwari Mar 2023

Adaptive Modified Rise-Based Quadrotor Trajectory Tracking With Actuator Uncertainty Compensation, Emmanuel Ogbanje Ijoga, William Mackunis, Krishna Bhavithavya Kidambi, Madhur Tiwari

Publications

This paper presents an adaptive robust nonlinear control method, which achieves reliable trajectory tracking control for a quadrotor unmanned aerial vehicle in the presence of gyroscopic effects, rotor dynamics, and external disturbances. Through novel mathematical manipulation in the error system development, the quadrotor dynamics are expressed in a control-oriented form, which explicitly incorporates the uncertainty in the gyroscopic term and control actuation term. An adaptive robust nonlinear control law is then designed to stabilize both the position and attitude loops of the quadrotor system. A rigorous Lyapunov-based analysis is utilized to prove asymptotic trajectory tracking, where the region of convergence …


Urban Air Mobility (Uam) Flight Path: Literature Review And Conceptual Design Of Uam Corridor Virtual Lane System Using “Tracks”, Immanuel Bankole Feb 2023

Urban Air Mobility (Uam) Flight Path: Literature Review And Conceptual Design Of Uam Corridor Virtual Lane System Using “Tracks”, Immanuel Bankole

Student Works

As the Urban Air Mobility (UAM) industry grows and becomes more popular, most of the conversations in the public domain are focused on the (electric Vertical Take-off and Landing) eVTOL aircraft and the physical infrastructure that will support these eVTOL aircraft. However, there is a lack of research on UAM traffic management and flight paths taken by aircraft between locations.

The United States (U.S.) Federal Aviation Administration has proposed the use of corridors to minimize the interaction between UAM operations and traditional air traffic as eVTOL aircraft perform flight activities. The government also acknowledges the need for additional structures (such …


Solar Sailing Adaptive Control Using Integral Concurrent Learning For Solar Flux Estimation, Luis Enrique Mendoza Zambrano, Riccardo Bevilacqua Jan 2023

Solar Sailing Adaptive Control Using Integral Concurrent Learning For Solar Flux Estimation, Luis Enrique Mendoza Zambrano, Riccardo Bevilacqua

Student Works

In the interest of exploiting natural forces for propellant-less spacecraft missions, this investigation proposes an adaptive control strategy to account for unknown parameters in the dynamic modeling of a reflectivity-controlled solar sail spacecraft. A Lyapunov-based control law along with integral concurrent learning is suggested to accomplish and prove global exponential tracking of the estimated parameters and states of interest, without satisfying the common persistence of excitation condition, which in most nonlinear systems cannot be guaranteed a priori. This involves estimating the solar flux or irradiance from the Sun to account for uncertainty and variation over time in this value. To …


Dual Quaternion Relative Dynamics For Gravity Recovery Missions, Ryan Kinzie, Riccardo Bevilacqua, Seo Dongeun Jan 2023

Dual Quaternion Relative Dynamics For Gravity Recovery Missions, Ryan Kinzie, Riccardo Bevilacqua, Seo Dongeun

Student Works

A dual quaternion modeling approach is compared to traditional modeling methods for formation flying spacecraft utilized for gravity recovery missions. A modeling method that has traditionally been used for gravity recovery missions is presented which models the motion of two formation flying spacecraft and a test mass. This is followed by the dual quaternion-based formulation for the equations of motion of the twelve degree-of-freedom coupled relative dynamics of formation flying spacecraft and a test mass. Lastly, utilizing data products from the Gravity Recovery and Climate Experiment Follow-On mission, a comparison of these two modeling methods is presented which proves the …


Experimental Validation Of Inertia Parameters And Attitude Estimation Of Uncooperative Space Targets Using Solid State Lidar, Alessia Nocerino, Roberto Opromolla, Giancarmine Fasano, Michele Grassi, Spencer John, Hancheol Cho, Riccardo Bevilacqua Jan 2023

Experimental Validation Of Inertia Parameters And Attitude Estimation Of Uncooperative Space Targets Using Solid State Lidar, Alessia Nocerino, Roberto Opromolla, Giancarmine Fasano, Michele Grassi, Spencer John, Hancheol Cho, Riccardo Bevilacqua

Student Works

This paper presents an experimental activity aimed at assessing performance of techniques for inertia and attitude parameters estimation of an uncooperative but known space target. The adopted experimental set-up includes a scaled-down 3D printed satellite mock-up, a spherical air bearing and a low-cost solid-state LIDAR. The experimental facility also comprises a motion capture system to obtain a benchmark of the pose (position and attitude) parameters and an ad-hoc designed passive balancing system to keep the centre of mass as close as possible to the centre of rotation. The LIDAR-based 3D point clouds, collected while the target rotates on the spherical …


Fostering Safer Evacuations Aboard Commercial Aircraft: A Problem-Solution Analysis, George Skinner Jan 2023

Fostering Safer Evacuations Aboard Commercial Aircraft: A Problem-Solution Analysis, George Skinner

Student Works

This problem-solution analysis analyzes factors impeding safe and orderly evacuations for the Federal Aviation Administration (FAA). Although rarely used, evacuation procedures are critical for keeping passengers safe during emergency situations. However, there are flaws in these procedures and many factors exist which make aircraft evacuations slow and dangerous. During a situation in which time is of the essence, these impediments can make the difference between an incident and a fatal accident. This report focuses on data gathered through full-scale evacuation simulations and analyzes shortcomings and strengths in three accidents. This information is then compared to current procedures and regulations that …


Noise Reduction Techniques In Commercial Aircraft Cabins, Hashem Hashem Jan 2023

Noise Reduction Techniques In Commercial Aircraft Cabins, Hashem Hashem

Student Works

Main sources of noise heard inside an aircraft cabin:

  • Engines
  • Airframe & control surfaces
  • Window vibrations
  • Passenger announcements & activities.


Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo Jan 2023

Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo

Student Works

Aircraft taxiing operations in the aerodrome were identified to consume the most jet fuel apart from the cruise phase of the flight. This was also well supported by various research associating taxi operations at large, congested airports, with high jet fuel consumption, high carbon emissions, and noise pollution. Existing literature recognised the potential to address the environmental issues of aerodrome taxi operations by operating External or Onboard Aircraft Ground Propulsion Systems (AGPS). Designed to power aircraft with sources other than their main engines, external Aircraft Ground Power Systems (AGPS) have shown the potential to significantly cut jet fuel consumption and …


Certification Basis For A Fully Autonomous Uncrewed Passenger Carrying Urban Air Mobility Aircraft, Steve Price Dec 2022

Certification Basis For A Fully Autonomous Uncrewed Passenger Carrying Urban Air Mobility Aircraft, Steve Price

Student Works

The Urban Air Mobility campaign has set a goal to efficiently transport passengers and cargo in urban areas of operation with autonomous aircraft. This concept of operations will require aircraft to utilize technology that currently does not have clear regulatory requirements. This report contains a comprehensive analysis and creation of a certification basis for a fully autonomous uncrewed passenger carrying rotorcraft for use in Urban Air Mobility certified under Title 14 Code of Federal Regulations Part 27. Part 27 was first analyzed to determine the applicability of current regulations. The fully electric propulsion system and fully autonomous flight control system …


Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik Dec 2022

Metal Organic Framework Modifications Of Structural Fibers, Marwan Al-Haik

Publications

A reinforced carbon composite can include a carbon sub­strate and a metal organic framework bonded to the carbon substrate. For example, a reinforced carbon composite can include a first layer, a second layer, and a resin adhered to the first layer and the second layer. The first layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate. The second layer can include a carbon substrate and a metal organic framework bonded to the carbon substrate.


Spacecraft Systems & Navigation, Christopher Vanacore Nov 2022

Spacecraft Systems & Navigation, Christopher Vanacore

Student Works

This textbook is steered towards higher educational course entailed in Commercial Space Operations. This textbook will be covering in detail Orbital Satellites, and Spacecraft. These topics are discussed according to their application, design, and environment. The power system, shielding and communication systems are reviewed along with their missions, space, environment and limitations. Any vehicle, whether manned or unmanned, intended for space travel is a spacecraft. A spacecraft's required systems and equipment depend on the information it will acquire and the tasks it will perform. Although their levels of sophistication vary widely, they re all subject to the harsh conditions of …


A Machine Learning Approach Towards Analyzing Impact Of Surface Weather On Expect Departure Clearance Times In Aviation, Dothag Truong, Shlok Misra, Godfrey V. D'Souza Nov 2022

A Machine Learning Approach Towards Analyzing Impact Of Surface Weather On Expect Departure Clearance Times In Aviation, Dothag Truong, Shlok Misra, Godfrey V. D'Souza

Publications

Commercial air travel in the United States has grown significantly in the past decade. While the reasons for air traffic delays can vary, the weather is the largest cause of flight cancellations and delays in the United States. Air Traffic Control centers utilize Traffic Management Initiatives such as Ground Stops and Expect Departure Clearance Times (EDCT) to manage traffic into and out of affected airports. Airline dispatchers and pilots monitor EDCTs to adjust flight blocks and flight schedules to reduce the impact on the airline’s operating network. The use of time-series data mining can be used to assess and quantify …


Ramping Up For Cost And Performance Improvements, Arthur Zucchetti Lechmann, Guilherme Henrique Lima, João Paulo Lucchi, Paulo Henrique Azevedo Santana, Pedro Kamikihara Nov 2022

Ramping Up For Cost And Performance Improvements, Arthur Zucchetti Lechmann, Guilherme Henrique Lima, João Paulo Lucchi, Paulo Henrique Azevedo Santana, Pedro Kamikihara

Student Works

The objective of this Research Project was to study the possible benefits of developing an improved Metering Control System. This study identified potential cost savings and reduced emissions through the greater use of a Metering Control System. The results of this research have indicated an annual cost reduction of $720,000 in fuel burn and a significant delay time reduction caused by accumulated ground traffic. In addition, during peak hours, it was concluded that savings could be potentially higher. Therefore, by optimizing the ground movement, it is also expected a lower level of CO2 emissions, an increased safety level due to …


Sme Coffee Hour: Human Factors: Dirty Dozennorms And Complacency, Linda Vee Weiland Oct 2022

Sme Coffee Hour: Human Factors: Dirty Dozennorms And Complacency, Linda Vee Weiland

Publications

Presentation about the relevance between communication, language, complacency and norms related to flight safety.


Rocket Measurements Of Electron Energy Spectra From Earth’S Photoelectron Production Layer, Glyn A. Collinson, Alex Glocer, Dennis Chornay, Robert Mitchell, Rob Pfaff, Tim Cameron, Nasa Goddard Space Flight Center, Rudy A. Frahm, Traci Rosnack, Chris Pirner, Ted Gass, Jim Clemmons, Aroh Barjatya, Steven Martin, Hassanali Akbari, Shantanab Debchoudhury, Rachel Conway, Francis Eparvier, Eftyhia Zesta, Nikolaos Paschalidis Aug 2022

Rocket Measurements Of Electron Energy Spectra From Earth’S Photoelectron Production Layer, Glyn A. Collinson, Alex Glocer, Dennis Chornay, Robert Mitchell, Rob Pfaff, Tim Cameron, Nasa Goddard Space Flight Center, Rudy A. Frahm, Traci Rosnack, Chris Pirner, Ted Gass, Jim Clemmons, Aroh Barjatya, Steven Martin, Hassanali Akbari, Shantanab Debchoudhury, Rachel Conway, Francis Eparvier, Eftyhia Zesta, Nikolaos Paschalidis

Publications

Photoelectrons are crucial to atmospheric physics. They heat the atmosphere, strengthen 28 planetary ambipolar electric fields, and enhance the outflow of ions to space. However, 29 there exist only a handful of measurements of their energy spectrum near the peak of 30 photoproduction. We present calibrated energy spectra of pristine photoelectrons at their 31 source by a prototype Dual Electrostatic Analyzer (DESA) instrument flown on July 11 32 2021 aboard the Dynamo-2 sounding rocket (NASA № 36.357). Photopeaks arising from 33 30.4nm He-II spectral line were observed throughout the flight above 120km. DESA also 34 successfully resolved the rarely observed …


Comprehensive Review Of Heat Transfer Correlations Of Supercritical Co2 In Straight Tubes Near The Critical Point: A Historical Perspective, Nicholas C. Lopes, Yang Chao, Vinusha Dasarla, Neil P. Sullivan, Mark Ricklick, Sandra Boetcher Aug 2022

Comprehensive Review Of Heat Transfer Correlations Of Supercritical Co2 In Straight Tubes Near The Critical Point: A Historical Perspective, Nicholas C. Lopes, Yang Chao, Vinusha Dasarla, Neil P. Sullivan, Mark Ricklick, Sandra Boetcher

Publications

An exhaustive review was undertaken to assemble all available correlations for supercritical CO2 in straight, round tubes of any orientation with special attention paid to how the wildly varying fluid properties near the critical point are handled. The assemblage of correlations, and subsequent discussion, is presented from a historical perspective, starting from pioneering work on the topic in the 1950s to the modern day. Despite the growing sophistication of sCO2 heat transfer correlations, modern correlations are still only generally applicable over a relatively small range of operating conditions, and there has not been a substantial increase in predictive capabilities. Recently, …


Introduction To Aerospace Flight Vehicles, J. Gordon Leishman Aug 2022

Introduction To Aerospace Flight Vehicles, J. Gordon Leishman

OER Main

The overarching concept of this eTextbook is to give students a broad-based introduction to the aerospace field, emphasizing technical content while making the material attractive and digestible. This eTextbook is structured and split into lessons centered around a 50-minute lecture period. Each lesson includes text content with detailed illustrations, application problems, a self-assessment quiz, and topics for further discussion. In addition, hyperlinks to additional resources are provided to support students who want to delve deeper into each topic. At the end of the eTextbook, there are many more worked examples and application problems for the student. While many lessons will …


Preliminary Study Of Shape-Memory Alloy Torsional Tubes As Thermal Management Actuators Under Non-Ideal Conditions, Paula Sanjuan Espejo, Samuel Desloover, Devon Hardy, Mark Ricklick, Frederick Calkin, David Foutch Jun 2022

Preliminary Study Of Shape-Memory Alloy Torsional Tubes As Thermal Management Actuators Under Non-Ideal Conditions, Paula Sanjuan Espejo, Samuel Desloover, Devon Hardy, Mark Ricklick, Frederick Calkin, David Foutch

Publications

Shape-memory alloys (SMAs) have been used in many engineering applications because of their shape-memory effect and pseudoelasticity. SMA behavior is well understood under steady and constant temperature and loading conditions, whereas transient and non-ideal conditions effects should be further investigated. In this research, SMA torque tubes are studied for use in thermal management applications as self-regulated actuators responding to a process fluid with changes in temperature, with the goal of improved system efficiency by keeping components at an optimal temperature. When utilized in a thermal management configuration, it is likely that the SMA’s thermal environment will be different than that …