Aerospace Engineering Commons^™

Effect Of Sulfur - Porous Carbon Cathode Morphology On The Discharge Process In Lithium-Sulfur Battery, Sabarinathan Pushparajsubramaniyan

Mechanical and Aerospace Engineering Theses - Archive

In the present era, Lithium-ion (Li-ion) batteries are most commonly used in all electronic devices, but the demand for alternative energy increases rapidly due to the catastrophic climate caused by excess use of fossil fuels in automobiles. Li-ion batteries cannot fully satisfy the need as its theoretical capacity is low, and the cathode cost is high. On the other hand, Lithium-Sulfur (Li-S) battery meets the requirement with the highest theoretical capacity of Sulfur 1672 mAh/g. Lithium anode and Sulfur cathode together form to be having the highest energy density. The highest energy capacity of Sulfur is achieved by the conversion …

Comparative Cfd Analysis Of The Effect Of Air And Liquid Cooling On The Form Factor Of Gpu Server, Ankit Bharatkumar Sutaria

Mechanical and Aerospace Engineering Theses - Archive

Artificial intelligence (AI) has becoming an important area which may significantly impact everyone’s daily life. This means a lot of high-performance chips such as high-performance CPU, GPU, FPGA (Field-programmable gate array), ASIC (application specific integrated circuit) devices may need. The thermal design power (TDP) of these chips are high, and now it is very common to see a processor TDP reaches as high as 300Watts[1]. When these high-power density processors are packaged together, the power density of the servers and compute boxes are significantly high. Traditional air-cooling is approaching its cooling capability limitation, especially when a cluster of racks is …

Design And Optimization Of Additively Manufactured Heat Sink And Heat Spreader For Microelectronics Cooling, Aditya Krishna Ganesh Ram

Mechanical and Aerospace Engineering Theses - Archive

High performance cooling is a critical requirement for modern microprocessors that generate large amounts of non-uniformly distributed heat. Metal heat spreaders and heat sinks have been traditionally used for thermal management. While the design of these components has traditionallly been restricted by manufacturability, in recent years, additive manufacturing has offered the capability to manufacture almost any design. This work analyzes and optimizes the performance of an additively manufactured heat sink and heat spreader. Computational heat transfer simulations were carried out to understand the variation of chip temperature and pressure drop for various designs. Discussion of key findings include the thermal …

Molecular Dynamics (Md) Thermal Simulations Of Molecular Bridging Across The Cathode-Separator Interface In Li-Ion Cell, Abhijeet Sundarrao Dhakane

Mechanical and Aerospace Engineering Theses - Archive

While Li-ion cells show outstanding electrochemical performance, their poor thermal transport characteristics results in reduced performance as well as significant safety concerns. The heterogeneous interface between cathode and separator plays a vital role in the dissipation of heat within a Li-ion cell. Previous studies showed that the cathode-separator interfacial thermal resistance contributes around 88% of total thermal resistance within the cell. In this research, thermal conductance across the cathode-separator interface is calculated using molecular dynamics simulations. Thermal transport in a pristine heterogeneous interface as well as interfaces functionalized with monolayers of APTES, nBTMS and MPTMS molecules is studied. The impact …

Computational Fluid Dynamics Analysis Of Inverted, Multi-Element Airfoils In Ground Effect, Michael Grabis, Ramesh K. Agarwal

McKelvey School of Engineering Graduate Student Theses & Dissertations

Formula SAE cars are formula-styled race cars designed to race on an autocross circuit. The autocross circuit is mostly comprised of turning sections as well as a limited amount of straight sections for passing other cars. Highly competitive cars in the competition implement aerodynamic devices to generate negative lift for the race car. This negative lift, or downforce, increases the amount of traction between the race car’s tires and the ground ultimately allowing the drivers to turn at faster speeds. Commonly used aerodynamic devices are a front and rear wing; the wing cross sections are defined by configurations of multiple …

Wireless Antenna Detection Of Electrostatic Discharge Events, Allen Andersen, Jr Dennison

Journal Articles

Wireless intraspacecraft communication technology is being developed for signal transfer on space missions to save weight and simplify the design. One consideration for this new technology is its interaction with space environmentinduced electrostatic discharges (ESDs). The short time scales of spacecraft ESD events result in broad frequency band signals that can interact with high-frequency wireless antennas. These interactions present a source of signal noise. However, they also present a possibility of in-flight wireless ESD monitoring. We present laboratory measurements of arcing on common spacecraft insulators using commercially available single-band 2.4-GHz and dual-band 2.4-/5.8-GHz Wi-Fi antennas. These wireless detections are shown …

Constellation Planning Methods For Sequential Spacecraft Rendezvous Using Multi-Agent Scheduling, Skylar A. Cox, Nathan B. Stastny, Greg Droge, David K. Geller

Space Dynamics Laboratory Publications

This paper addresses the RPO constellation assignment problem by developing a responsive utility function for tasking a constellation of LEO satellites to several spacecraft servicing tasks. The paper develops the utility function that considers both value of servicing RSO spacecraft in conjunction with the associated ΔV cost. A highly-capable and operationally-relevant task allocation method, called the consensus-based bundle algorithm (CBBA), is leveraged for distributed processing and task allocation. This paper demonstrates that this methodology provides a robust technique for RPO constellation management.

Comparative Rack Level Cfd Analysis Of Air To Hybrid Cooling Data Center, Jay Umeshkumar Parekh

Mechanical and Aerospace Engineering Theses - Archive

The demand of data storage in the world is increasing, with this increase, demand for large data centers is growing. In response, we need to look for energy-efficient solutions to reduce the energy consumptions of the data centers. We want to reduce the energy used for cooling while keeping the data center equipment temperature in allowable range in high power density data center. The liquid or hybrid cooled servers are the alternatives that may be used instead of traditional air-cooled servers at Rack Level for the cooling power - different inlet temperatures and different percentage of hybrid cooling. This will …

Feasibility Of Circular Orbits For Proximity Operations In Strongly Perturbed Environments Around Uniformly Rotating Asteroids, Nicholas Peter Liapis

Doctoral Dissertations and Master's Theses

Asteroids have been mapped and observed since 1801 when an Italian astronomer Guiseppe Piazzi discovered Ceres (Serio, Manara, & Sicoli, 2002). Since then, asteroids have been growing in popularity throughout the scientific community because they are thought to hold the information we need to understand how the solar system developed and why life exists on earth, as well as potential precious resources. This research studies different types of orbits that have been performed to date around asteroids and how they can be reworked to require less control effort. Different types of missions that have been sent to asteroids are discussed, …

Angles-Only Ekf Navigation For Hyperbolic Flybys, Iggy Matheson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Space travelers in science fiction can drop out of hyperspace and make a pinpoint landing on any strange new world without stopping to get their bearings, but real-life space navigation is an art characterized by limited information and complex mathematics that yield no easy answers. This study investigates, for the first time ever, what position and velocity estimation errors can be expected by a starship arriving at a distant star - specifically, a miniature probe like those proposed by the Breakthrough Starshot initiative arriving at Proxima Centauri. Such a probe consists of nothing but a small optical camera and a …

Multiple Imu Sensor Fusion For Suas Navigation And Photogrammetry, Matthew Givens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Inertial measurement units (IMUs) are devices that sense accelerations and angular rates in 3D so that vehicles and other devices can estimate their orientations, positions, and velocities. While traditionally large, heavy, and costly, using mechanical gyroscopes and stabilized platforms, the recent development of micro-electromechanical sensor (MEMS) IMUs that are small, light, and inexpensive has led to their adoption in many everyday systems such as cell phones, video game controllers, and commercial drones. MEMS IMUs, despite their advantages, have major drawbacks when it comes to accuracy and reliability. The idea of using more than one of these sensors in an array, …

Control And Stability Of Upper Stage Launch Vehicle With Hybrid Arc-Ignition Attitude Control System, Steven Russell Bennett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah State University Propulsion Research Laboratory (USUPRL) has recently made significant developments in the area of hybrid rocket systems. This type of propulsion system incorporates a solid fuel and a gas or liquid oxidizer. Hybrid rocket systems are known for their inherent safety, reliability, and restart capability. Over the last several years, the USUPRL has successfully built and tested a hybrid rocket system comprising acrylonitrile butadiene styrene (ABS) plastic and gaseous oxygen (GOX). The system was demonstrated to be fully functional during ground, vacuum, and sub-orbital flight testing. Continuing forward, the USUPRL endeavors to extend the capabilities of this …

Advanced Photogrammetric Modeling Of Dranoc Kullas Using Small Unmanned Aircraft Systems, George Gebert, Liam Griffin, Justin Lawlor, Lauren Davis, Kylee Vander Velde, Sami Ali

Student Works

Small unmanned aircraft systems (sUAS), also known as drones, offer new capabilities for cultural heritage preservation activities. Student researchers from Embry-Riddle Aeronautical University have applied photogrammetric techniques based upon sUAS captured imagery to assist with historical site documentation and cultural heritage preservation in the Republic of Kosovo. Imagery from three locations -- Isniq, Dranoc and Junik -- highlight this work. Student researchers created georectified orthomosaics and 3D virtual objects. At each of these three locations the object of interest was a type of building known as a kulla. These kullas are fortified homes built for protecting large families and are …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch

PRC-Affiliated Research

Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch

PRC-Affiliated Research

In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch

PRC-Affiliated Research

In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch

PRC-Affiliated Research

Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 1. Drift And Diffusion Flux Closures, Sarma L. Rani, Vijay K. Gupta, Donald L. Koch

PRC-Affiliated Research

In this two-part study, we present the development and analysis of a stochastic theory for characterizing the relative positions of monodisperse, low-inertia particle pairs that are settling rapidly in homogeneous isotropic turbulence. In the limits of small Stokes number and Froude number such that , closures are developed for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions. The theory focuses on the relative motion of particle pairs in the dissipation regime of turbulence, i.e. for pair separations smaller than the Kolmogorov length scale. In this regime, the theory approximates the fluid …

Clustering Of Rapidly Settling, Low-Inertia Particle Pairs In Isotropic Turbulence. Part 2. Comparison Of Theory And Dns, Sarma L. Rani, Rohit Dhariwal, Donald L. Koch

PRC-Affiliated Research

Part 1 (Rani et al. J. Fluid Mech. , vol. 871, 2019, pp. 450–476) of this study presented a stochastic theory for the clustering of monodisperse, rapidly settling, low-Stokes-number particle pairs in homogeneous isotropic turbulence. The theory involved the development of closure approximations for the drift and diffusion fluxes in the probability density function (p.d.f.) equation for the pair relative positions $\boldsymbol{r}$ . In this part 2 paper, the theory is quantitatively analysed by comparing its predictions of particle clustering with data from direct numerical simulations (DNS) of isotropic turbulence containing particles settling under gravity. The simulations were performed at …

Keeping Your Library Relevant For Your Users- Engine Parts Petting Zoo, Gabriele Hysong

Midwest Business Librarian Summit (MBLS)

As corporate libraries are downsized or even closed how do information professionals keep their libraries relevant?

Comparative Analysis Of Small Unmanned Aircraft Systems Operations Manuals, Stephen M. Cigal

Student Works

With over 100,000 remote pilots in the United States, individuals and companies are rapidly incorporating unmanned aircraft system technologies into their everyday life and businesses models. The companies that use these technologies must comply with federal and state regulations in order to maintain a safe environment to operate. These operations must also be accepted by the general public. Since the FAA regulations for small unmanned aircraft systems (sUAS) went into effect in 2016, supplemented by additional state and/or local requirements, some companies have generated operations manuals (OM) to ensure consistent, safe flight that meets these requirements. By analyzing the OM’s …

How Vision Governs The Collective Behaviour Of Dense Cycling Pelotons, J. Belden, Mohammad M. Mansoor, A. Hellum, S. R. Rahman, A. Meyer, C. Pease, J. Pacheco, S. Koziol, Tadd T. Truscott

Mechanical and Aerospace Engineering Faculty Publications

In densely packed groups demonstrating collective behaviour, such as bird flocks, fish schools or packs of bicycle racers (cycling pelotons), information propagates over a network, with individuals sensing and reacting to stimuli over relatively short space and time scales. What remains elusive is a robust, mechanistic understanding of how sensory system properties affect interactions, information propagation and emergent behaviour. Here, we show through direct observation how the spatio-temporal limits of the human visual sensory system govern local interactions and set the network structure in large, dense collections of cyclists. We found that cyclists align in patterns within a ± 30° …

Computational Analysis Of 3d Lattice Structures For Skin In Real-Scale Camber Morphing Aircraft, Bashir Alsaidi, Woong Yeol Joe, Muhammad Akbar

Mechanical and Manufacturing Engineering Faculty Research

Conventional or fixed wings require a certain thickness of skin material selection that guarantees structurally reliable strength under expected aerodynamic loadings. However, skin structures of morphing wings need to be flexible as well as stiff enough to deal with multi-axial structural stresses from changed geometry and the coupled aerodynamic loadings. Many works in the design of skin structures for morphing wings take the approach either of only geometric compliance or a simplified model that does not fully represent 3D real-scale wing models. Thus, the main theme of this study is (1) to numerically identify the multi-axial stress, strain, and deformation …

Range Of Motion Evaluation Of A Final Frontier Design Iva Spacesuit Using Motion Capture, Ryan L. Kobrick, Nicholas Lopac, Chase Covello, Benjamin Banner, Theodore Southern, Nikolay Moiseev

Publications

Embry-Riddle Aeronautical University’s Spacesuit Utilization of Innovative Technology Laboratory (S.U.I.T. Lab) is focused on improving human performance in spaceflight by concentrating on spacesuit research for intravehicular activities (IVA) and extravehicular activities (EVA). The design and execution of range of motion (ROM) protocols in an experimental setting will provide insight on the functions and restrictions of spacesuits, aiding in current and future designs or modification. The S.U.I.T. Lab worked with Final Frontier Design (FFD) to provide a quantitative analysis protocol for seated arm mobility of their NASA Flight Opportunities Program (FOP) IVA spacesuit. The lab used reflective tracking markers on three …

Keeping Your Distance: The Science Of Turns-Around-A-Point And Ground Reference Maneuvers, Nihad E. Daidzic

Aviation Department Publications

Ground reference maneuvers are more important than you may think. Frequently regarded as unimportant or boring, ground reference maneuver training is often limited to a few minutes of flight instructor demonstration and brief student practice.

Manipulating Fiber Orientation For The Reduction Of Warpage In Carbon Fiber Composite Sandwich Panels, Landon Burnley, Gabrielle Correia

Materials Engineering

Safran Cabin (Santa Maria, CA), previously known as Zodiac Aerospace, designs and manufactures interior cabin components for private and commercial aircraft. Carbon fiber face sheets have recently been incorporated in their overhead luggage bin assemblies which utilize a composite sandwich panel design, in order to provide additional stiffness to the previous glass fiber sandwich panels. Since the introduction of carbon fiber in these luggage bin panels, Safran has experienced an increase in warpage during manufacturing. When inspected by quality control, the panels are tested mimicking how they are installed in aircraft. If the panels do not meet specifications, the warped …

Design Principles And Preliminary Testing Of A Micropropulsion Electrospray Thruster Research Platform, Will Alan Mcgehee

Master's Theses

The need for micropropulsion solutions for spacecraft has been steadily increasing as scientific payloads require higher accuracy maneuvers and as the use of small form-factor spacecraft such as CubeSats becomes more common. Of the technologies used for this purpose, electrospray thrusters offer performance that make them an ideal choice. Electrosprays offer high accuracy impulse bits at low power and high efficiency, and have low volume requirements. Design choice reasoning and preliminary testing results are presented for two electrospray thruster designs. The first thruster, named the Demonstration thruster, is operated in atmospheric conditions and serves as a highly visible example of …

The Effects Of Atomic Oxygen On Patch Antenna Performance And Lifetime, Max J. Barta

Master's Theses

The space environment is a volatile and challenging place for satellites to survive in. For Low Earth Orbiting (LEO) satellites, atomic oxygen (AO) is a constant corrosive effect that degrades the outer surface of satellites over long durations. Atomic oxygen exists in the atmosphere between 180 and 675 km and has a relatively high energy at 4.5 eV, which allows AO to break molecular bonds in materials on the surfaces of spacecraft. As the number and complexity of CubeSat missions increase, there is an increased risk that AO degradation on commercial off the shelf parts (COTS), such as antenna, could …

Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan

Mechanical Engineering Research Theses and Dissertations

In impact mechanics, the collision between two or more bodies is a common, yet a very challenging problem. Producing analytical solutions that can predict the post-collision motion of the colliding bodies require consistent modeling of the dynamics of the colliding bodies. This dissertation presents a new method for solving the two and multibody impact problems that can be used to predict the post-collision motion of the colliding bodies. Also, we solve the rigid body collision problem of planar kinematic chains with multiple contacts with external surfaces.

In the first part of this dissertation, we study planar collisions of Balls and …

A Set-Theoretic Model Reference Adaptive Control Architecture With Dead-Zone Effect, Ehsan Arabi, Tansel Yucelen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

By introducing a system error dependent learning rate, the recently proposed set-theoretic model reference adaptive control architecture provides user-defined worst-case performance guarantees on the system error between an uncertain dynamical system of interest and a given reference model. In this architecture, the adaptation process is always active. However, it is of practical interest to stop the adaptation process when it is not needed (i.e., in the presence of small system errors). Motivated from this standpoint, we present a new set-theoretic model reference adaptive control architecture with dead-zone effect. The key feature of our framework utilizes a modified and continuous generalized …