Engineering Commons^™

Steady State And Transient Analysis Of Heat Transfer In A Porous Fin With Radially Outwards Pressure-Driven Flow, Muhammad Mehdi Abbas

Mechanical and Aerospace Engineering Theses - Archive

Thermal management and energy storage problems often utilize extended surfaces, also known as fins for enhanced heat transfer. Today fins are used in a wide range of devices including but not limited to microelectronic components and large heat exchanger. Traditional fins as well as porous fins with flow orthogonal to fin direction have been subject of past research. There is very few academic literature available on porous fins with pressure driven flow along fin direction. While thermal conduction is usually the dominant mode of heat transfer in a solid fin, the use of porous fins that include advective thermal transport …

Development Of Vortex Box (Vbox) And Vortex Tip (Vtip) Filament Free-Wake Rotor Models, Casey Will Matsler

Mechanical and Aerospace Engineering Theses - Archive

Rotor models span from simple static and first order expressions to high fidelity, numerical computations and across the spectrum each model is good for different purposes. The use of models has improved with time and technological capability but choosing the right model for the task is important. A survey of rotor models is performed to identify a rotor model flexible enough for providing high to moderately high-fidelity results without significantly sacrificing computational time. The model chosen is intended to be for general purposes and applicable across a wide range of operating conditions. From the survey, a blade element rotor model …

Evaluation Of Solder Alloys For Bga Package: A Comparative Reliability Study Using Ansys Computational Analysis, Yashvanth Muthegowda

Mechanical and Aerospace Engineering Theses - Archive

Temperature cycling failure of solder joints in Ball Grid Array (BGA) packages has become a critical issue in electronic manufacturing. This thesis specifically characterizes three different lead-free solder alloys (Pure Indium, SAC-387, and SAC-Q) in BGA solder joints using two different printed circuit board (PCB) thicknesses (1mm and 0.7 mm). The analysis considers the non-uniform temperature distribution caused by the main heat source, the die, and the resulting deformation of the package due to the mismatch in the coefficient of thermal expansion (CTE) between components used in BGA. Finite element (FE) models are created in ANSYS mechanical package environment to …

Advancement Of An Inhouse Aerospace Vehicle Design Synthesis System Through The Introduction Of A Novel Database-Knowledgebase System And By Improving The Geometry And Aerothermodynamic Disciplinary Processes, Samuel Atchison

Mechanical and Aerospace Engineering Theses - Archive

Throughout the years of aerospace vehicle design, the process in which a vehicle is designed has drastically improved from being primarily developed through trial and error, to using sophisticated synthesis systems. While the trial-and-error process had its uses with providing the fundamental knowledge of how aircraft behave and can be designed, the increase in knowledge and technology allowed the possibility of more vehicle configurations to be explored without the need to build each one. This increase should have led to a revolution of vehicle designs, and while there have been some novel ones, it seems that the general design of …

Numerical Modeling Of Damper Configuration And Arrangements For Analysing Thermal Stratification In Modular Air Handling Units, Rohit Antony Raymonds

Mechanical and Aerospace Engineering Theses - Archive

Although air handling units are well established and maturated there are opportunities to optimize and improve the overall thermal and flow performance to reduce the carbon footprint of an air-cooled data center. Airside economization (ASE) arrangement to use cold outdoor air to minimize mechanical cooling energy was substantial progress in minimizing the power usage effectiveness (PUE) for data centers. ASE is an arrangement of ducts and dampers with the necessary controls to meet the cooling requirements. Dampers play a significant role in regulating the mass flow rate of the air and in mixing the two air streams: cold outdoor air, …

Effects Of Metal Organic Frameworks In Polyether Block Amide Elastomer, Joe Alex

Mechanical and Aerospace Engineering Theses - Archive

Metal-organic frameworks (MOFs) are highly porous materials that find extensive applications in gas absorption and separation in recent years. These hybrid materials can be designed with specific pore sizes and voids to selectively filter gases. PEBAX (MV 1074) is a commercially available polyether block amide copolymer generally used in gas separation applications. In this study, we characterize two different MOFs by means of a dispersion study and create a medium for them to be evenly dispersed into the aforementioned copolymer matrix. Polymer composite fibers are extruded using a twin-screw extruder and a winding unit at pre-determined parameters for winding speed …

Impact Of Immersion Cooling On Thermo-Mechanical Properties Of Non-Halogenated Core, Mohan Sai Ramalingam

Mechanical and Aerospace Engineering Theses - Archive

The rise in demand for modern high-power systems, which require fast processing and frequent data storage, has resulted in an exceptional and unprecedented increase in power density and heat generation within data centers. This eventually led to the need for advanced cooling techniques that can address the challenges of managing the heat produced by the data centers. As per Moore's law and Dennard's scaling, the power densities of chips and the heat flux generated by servers are continuously increasing. [1] As a result, the dissipation of heat at the chip level has also increased, posing a significant challenge for thermal …

Compliant Robot Manipulator For Transurethral Diagnosis, Samson A. Adejokun

Mechanical and Aerospace Engineering Dissertations - Archive

ABSTRACT: Minimally invasive procedures employ continuum manipulators, however, the internal human anatomy presents challenges relating to size, dexterity, and workspace for these manipulators. This research presents modeling, kinematic analysis, limited prototyping, and characterization of a micro-robotic manipulator to assess viscoelastic tissue properties of the bladder through transurethral palpation towards the diagnosis of bladder dysfunction, urinary incontinence, and early-stage bladder cancer. The proposed micro-robot consists of two subsystems; a unique 4mm outer diameter tendon-driven continuum segment from assembled “vertebrae” components with male and female snap-in features for joint assembly, an elastic tube encompassing each joint for controlled compliance and structural integrity …

Development Of Femtosecond Laser Electronic Excitation Tagging (Fleet) And Femtosecond Two-Photon Absorption Laser Induced Fluorescence (Fs-Talif) Diagnostics For Species Number Density And Velocity Measurements In Arc-Jet Flows, Daniel William Palmquist

Mechanical and Aerospace Engineering Dissertations - Archive

ABSTRACT: Arc-jet flows are the only ground-test facilities that can recreate hypersonic high-enthalpy flight conditions for long durations. Characterizing these complex flow regimes, generally under thermo-chemical non-equilibrium, is crucial to establishing a relationship between the ground-test environment and flight conditions. This work presents the development of two innovative and world’s first successful application of advanced non-intrusive laser-based diagnostic techniques for characterizing the 1.6 MW ONR-UTA Arc-Heated Wind Tunnel, Leste’s plasma flow. The arc-jet flow represents a unique challenge for the application of laser-based diagnostics due to the highly emitting background across a wide spectral range. Femtosecond Laser Electronic Excitation Tagging …

Fatigue Performance Modeling In Advanced Out-Of-Autoclave Composites For Aerospace Applications, Grayson Reid Curry

Mechanical and Aerospace Engineering Theses - Archive

Increased application of composite materials in the military and civil applications renewed the interest to development of high-fidelity methodologies for predicting their performance characteristics. Besides the traditional autoclave processed structural composites such as IM7/8552 and IM7/977-3 widely used on various platforms, novel materials such IM7/5320-1 suitable for Out-of-Autoclave (OoA) cure became of interest. Static and fatigue performance prediction of Open-Hole quasi-isotropic laminates made from IM7/5320-1 was performed in this work by using the Finite Element Analysis software BSAM. Progressive failure simulation including delaminations, matrix cracks and fiber failure was performed. Regularized eXtended Finite Element Methods (RXFEM) was used for mesh …

Electrochemical Investigation Of Copperzirconium Based Metallic Glass Cu₅₁Zr₃₀Hf₁₄Ag₅, Tamim Mohammad Ahmad

Theses

This thesis is concerned with the electrochemical investigation of the copper-zirconium

based metallic glass Cu₅₁Zr₃₀Hf₁₄Ag₅. Studying the corrosion behavior of the novel melt-spun metallic glass ribbons contributes to further research on the possibility of building future bio-implants. The objectives of this thesis are to synthesize the metallic glass ribbons which are free from cytotoxic elements using melt spinning technique, verify their amorphous nature using X-ray diffraction method, study the corrosion behavior using Potentiodynamic polarization and Electrochemical Impedance Spectroscopy in different acidic, neutral and basic solutions, and finally examine the surface morphology of …

Augmented State Linear Covariance Applications For Nonlinear Missile Engagements, Jeffrey Scott Clawson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sustained actuator saturation is a common occurrence for missile engagements. The saturation nonlinearity creates some difficulty for high-fidelity linear analysis methods. This dissertation investigates three methods of modeling actuator saturation in an advanced linear analysis. The linear covariance tools from this dissertation run extremely fast and provide several advantages over other linear missile engagement analysis methods. First, a simulation is developed and validated for a target engagement scenario without actuator saturation. Next, saturations are introduced to the problem, along with the first analysis method: statistical linear covariance analysis. This method combines the augmented state linear covariance framework with the statistical …

High Efficiency Angles-Only Space-Based Approaches For Geosynchronous Orbit Catalog Maintenance With Sparse Information, Louis M. Tonc

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The thesis of this dissertation proposes a novel filter algorithm to improve tracking and catalog maintenance of uncooperative satellites and other Resident Space Objects (RSOs) in Geosynchronous Equatorial Orbit (GEO). Tracking can be supported by space-based tracking from observer satellites (OBSs). Practical limitations can lead to long time gaps between measurement updates when tracking RSOs from an OBS, which may induce a loss of fidelity or divergence of the estimation algorithm. The Extended Kalman filter (EKF) is commonly used for tracking RSOs but it diverges as a consequence of nonlinearity in the dynamics and nonlinearity in the optical measurements from …

Characterizing Energy Dissipation Of Shallow-Water Wave Breaking In A Storm Surge, Hunter Boswell, Guirong Grace Yan, Wouter Mostert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here we present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. The storm surge depth, beach slope, and wave amplitude are varied to study the dependence of energy dissipation in the breaker on wave and bathymetric parameters. We classify wave breaker types and find a separation between …

Mechanical And Thermal Performance Of Additively Manufactured Digital Materials, Layth Muayyad Ahmad

Mechanical and Aerospace Engineering Theses - Archive

Over the past decades, additive manufacturing has become a critical material processing tool. All ranges of materials including polymers, composites, metals, and ceramics can be used to fabricate structures with complex geometries that are nearly impossible to build using conventional fabrication process. Recently, additive manufacturing methods to build polymeric structures have been advanced significantly. In particular, the emergence of multi-material printers has made it possible to seamlessly print hybrid and digital materials where materials components and compositions are digitally varied to construct fully tailored material system. In this work, using a commercially available polyjet printer (Stratasys J850 Prime 3D printer), …

Parametric Multi-Objective Optimization Of Cold Plate For Single-Phase Immersion Cooling, Geevarghese Joseph Nattasseriedathil

Mechanical and Aerospace Engineering Theses - Archive

The increasing demand for high performance computing in applications such as Internet of Things, Deep Learning, Big data for crypto-mining, virtual reality, healthcare research on genomic sequencing, cancer treatment etc. has led to the growth of hyper scale datacenters. To meet the cooling energy demands of HPC datacenters efficient cooling technologies must be adopted. Traditional air cooling, direct to chip liquid cooling and immersion are some of those methods. Among all, Liquid cooling is superior compared to various air-cooling methods in terms of energy consumption. Direct on-chip cooling using cold plate technology is one such method used in removing heat …

Simulating Dielectric Barrier Plasma Actuators With Varying Geometries, Cass Wiederkehr

Mechanical Engineering Undergraduate Honors Theses

The idea of Ionic Wind Propulsion has long been a topic of research for whether or not it can be used as a practical power source for flight. MIT researchers proved in 2018 that a plane with zero moving parts powered by Ionic Wind Propulsion was possible, and sustained flight could work with an internal power supply. However, due to the thin wire electrodes required to generate the ion cloud that made such propulsion possible, large amounts of drag rendered the plane extremely inefficient and impractical. Dielectric Barrier Discharge Devices (DBDs) are being investigated as to whether they can serve …

A Systematic Study Into The Design And Utilization Of Burn Wire As A Means Of Tensioning And Releasing Spacecraft Mechanisms Through Applied Joule Heating, Chandler Dye

Mechanical Engineering Undergraduate Honors Theses

The joule heating characteristics of Nichrome burn wires, often used as a thermal cutting device in mechanisms designed to fasten and release CubeSat deployables, are examined in the following thesis. Wires ranging from 0.125 inches to 2 inches long, and diameters of 30 Ga and 40 Ga, are investigated through analytical calculations and thermal simulations based on heat transfer due to joule heating, and through physical circuitry-based experiments. The temperature data is used to generate heating curves to predict the time it takes for Nichrome wires to fail under varying testing parameters. This research aims to catalog a series of …

Innovation For The Air: A Brief History Of Worldwide Aviation, Lauren Plumley

Honors Program: Senior Projects (Public)

The purpose of this report is to present a brief but comprehensive overview of the variety of innovations related to aviation, and to discuss their impact on scientific progress over the course of human history. Relevant discoveries from the fields of physics and aerodynamics, and the numerous technologies built based upon these discoveries, are discussed over a period ranging from ancient times to the twenty-first century. The scope of this report is an overview of the development of powered and unpowered aircraft, including lighter-than-air, heavier-than-air, and aerospace technologies. Aviation developments were generally not limited to one specific country or person, …

Investigation Of Dynamic Hybrid Rans-Les Turbulence Modeling For Cfd Simulation Of A Normal Jet In Crossflow, Cole Simmonds

Mechanical Engineering Undergraduate Honors Theses

The jet in crossflow is a canonical flow feature in many natural and engineered systems, ranging from pollutant dispersal in exhaust discharge to film cooling of high-temperature components in modern propulsion systems. The ability to computationally predict the flow features of jets in crossflow accurately and efficiently is therefore important for analysis and design for a wide variety of applications. In this study the capabilities of the dynamic hybrid RANS-LES (DHRL) turbulence modeling technique are investigated and compared to an industry standard Reynolds-averaged Navier-Stokes model (k-omega SST) in order to quantify the accuracy and computational cost of the two approaches. …

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

Open Access Theses & Dissertations

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

Sealion Cubesat Mission Architecture Using Model Based Systems Engineering With A Docs As Code Approach, Kevin Yi-Tzu Chiu

Mechanical & Aerospace Engineering Theses & Dissertations

CubeSats are a growing population within the space industry. Every year, universities launch numerous amounts of CubeSats due to their inexpensive cost of development, launch, and deployment. However, this comes with numerous challenges. As the number of university-CubeSats grow, so too do the numbers that fail. With development teams consisting mainly of students with little to no training, proper and yet easy to use tools or methods should be implemented to help ensure mission success. Especially in the critical stages of planning before and during development, a technical approach to quickly track life cycle development of a CubeSat is needed. …

Smartphone Video Guidance Sensor In High-Altitude Uav Precision Landing, Joao Leonardo Silva Cotta

Theses and Dissertations

The Smartphone Video Guidance Sensor (SVGS) is an emerging technology developed by NASA Marshall Space Flight Center that uses a vision-based approach to accurately estimate the six-state position and orientation vectors of an illuminated target of known dimensions with respect to a coordinate frame fixed to the camera. SVGS is a software-based sensor that can be deployed using a host platform’s resources (CPU and camera) for proximity operations and formation flight of drones or spacecraft. The SVGS output is calculated based on photogrammetric analysis of the light blobs in each image; its accuracy in linear and angular motion at different …

Heat Transfer In Microchannel Compact Heat Exchanger, Mohammed Al-Khateri

Theses

This study aims to investigate heat transfer in a miniaturized channel heat exchanger and effectiveness for given real-life design. The main objective of the study is to develop and build a high-performance heat exchanger for thermal management in automotive application using typical radiator manufacturing techniques. This research uses experimental and model-based investigation. It conceptualizes the Miniaturized Channel Heat Exchangers (MCHX) model-based study for demonstrating the design of miniaturized channel heat exchangers, manufacture, and study the heat exchanger effectiveness by validating the developed mathematical model experimentally. The proposed design of the MCHX is to use extruded tubes containing miniaturized channels as …

2023 Spring Graduate Recognition Program, Propulsion Research Center, Robert Frederick

PRC Graduate Recognition

This program includes the graduate recognition program for spring 2023. Includes photographs, upcoming events, recent publications, and student profiles.

Multifunctional Additive Manufacturing And Multiphysics Numerical Investigations Of Carbon Fiber Structural Battery Composite Using A Drop-On-Demand Method With In-Situ Consolidation, Xiangyang Dong, Yuekun Chen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Lightweight Carbon Fiber Structural Battery Composite Has Great Potential in Increasing Structural Energy Storage Efficiency for Multifunctional Applications. However, It is Still Challenging to Design Carbon Fiber Multifunctional Composite Due to Lack of Proper Manufacturing Methods. in This Study, an Integrated Multifunctional Design and Fabrication Approach is Developed by Combining a Drop-On-Demand Additive Manufacturing Method with a Multiphysics Numerical Model to Guide the Development of the New Multifunctional Composite. through Deposition with In-Situ Consolidation, the Function and Thickness of Each Carbon Fiber Layer as Well as its Fiber Volume Fraction Are Accurately Controlled. Decreasing Layer Thickness Improves Flexural Properties. the …

Rendezvous And Proximity Operations In Cis-Lunar Space, Khalid Jebari

Theses and Dissertations

As interest in Moon exploration grows and efforts to establish an orbiting outpost intensify, accurate modeling of spacecraft dynamics in cis-lunar space is becoming increasingly important. Contrary to satellites in Low Earth Orbit (LEO) where it takes around 5 ms to communicate back and forth with a ground station, in the Moon’s orbit it can take up to 2.4 seconds to do so. This delay in communication can make the difference between a successful docking and a catastrophic collision for a remotely controlled satellite. Moreover, due to the unstable nature of trajectories in cis-lunar space, it is necessary to design …

Trajectory Energy Management For Ectol: Examination Of Battery Discharge Under Two Flight Profiles, Denner Campos Cunha

Theses and Dissertations

The expanding industry of electric airplanes presents a significant regulatory challenge for aviation authorities worldwide. The first step towards achieving a precise Trajectory Energy Management (TEM) is to understand how the powertrain behaves during the operation. Therefore, this work examined the battery performance of an eCTOL, the Pipistrel Velis Electro, under two different prescribed flight profiles and take-off weights. Flight 1, a destination trip profile, was conducted with a gross weight of 1146 lbs and a constant power setting of 22 kW during the cruise segment, while Flight 2, a local training flight profile, was conducted with a gross weight …

Flight Test Evaluation Of The B-1b Lancer For The Heavy Bomber Mission, Robert William Gates

Theses and Dissertations

Copyright held by author

The Effect Of Biodiesel Blend Composition On Jet Aircraft Airframe Fuel System Components & Materials, Elise Aurora Medhus

Theses and Dissertations

In the aviation industry, biodiesel is a clean-burning alternative to petroleum-based jet fuel and has been shown to reduce particle emissions from aircraft engines. This thesis studies the impact of biodiesel on aircraft airframe fuel system components & materials with corrosion-resistant surface treatments. The goal is to identify areas for optimization to increase the use of higher blends in jet aircraft engines to further reduce emissions. The work performed involved testing the corrosion resistance of several aluminum samples, steel samples, and non-metallic materials in numerous biodiesel blends ranging from B05 to B100. The testing method used was the Assessment of …