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Aerospace Engineering Commons

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2022

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Articles 451 - 472 of 472

Full-Text Articles in Aerospace Engineering

Nanobubble Capillary Force Between Parallel Plates, Eric Bird, Zhi Liang Jan 2022

Nanobubble Capillary Force Between Parallel Plates, Eric Bird, Zhi Liang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Aggregation of Fine or Ultrafine Particles in Liquid Due to the Nanobubble (NB) Bridging Capillary Force is a Key Process for Many Industrial Applications. the Magnitude and Direction of the NB Capillary Force (NBCF) Are Directly Affected by the Geometry of the NB Gas Bridge between Two Adjoining Particles. Although the NBCF Can Be Accurately Measured using Experimental Techniques, It is Very Challenging to Monitor the Images of a NB Capillary Bridge in Nanoscale Spatial Resolution in NBCF Measuring Experiments. as a Result, the Capillary Force Model that Predicts the Dependence of the NBCF on the Geometry of the …


Investigations Of The Low Temperature Combustion Regions And Emissions Characteristics Of Aerospace F24 In A Constant Volume Combustion Chamber And A Common Rail Direct Injection Ci Engine, Richard C. Smith Iii Jan 2022

Investigations Of The Low Temperature Combustion Regions And Emissions Characteristics Of Aerospace F24 In A Constant Volume Combustion Chamber And A Common Rail Direct Injection Ci Engine, Richard C. Smith Iii

College of Graduate Studies: Theses & Dissertations

A study was conducted to investigate the low temperature combustion (LTC) regions of aerospace F24 and ULSD in the static setting of a CVCC and the dynamic setting of a CRDI research engine. This research is conducted to reduce in-cylinder emissions by understanding and implementing a technique to achieve an extended LTC. Emissions data for this study were collected during the operation of the CRDI research engine with a MKS 2030 FTIR and an AVL Microsoot 483. The parameters researched within the static setting of the CVCC included the determinations of the cool flames and NTC regions within the LTHR …


Modeling And Experimentation Of Buckling Of Composite Deployable Booms Under Bending, Christopher D. Rehberg Jan 2022

Modeling And Experimentation Of Buckling Of Composite Deployable Booms Under Bending, Christopher D. Rehberg

Electronic Theses and Dissertations, 2020-2023

This thesis presents experimental and finite element analysis results of eccentrically loaded carbon-fiber composite booms that can deploy solar sails. Using the collapsible tubular mast design along with the geometry from the upcoming Advance Composite Solar Sail System mission, short composite booms segments were manufactured for testing. New clamps were also designed to allow a column bending test to achieve eccentric loading. As buckling through eccentric loading has not previously seen much research, the geometry and composite layups were simplified to allow for ease of manufacturing and verification. The work presented here shows that a finite element simulation, using a …


Energy Based Diagnostics Of Cfd: Revealing New Insights To Complex Aerodynamics, George Loubimov Jan 2022

Energy Based Diagnostics Of Cfd: Revealing New Insights To Complex Aerodynamics, George Loubimov

Electronic Theses and Dissertations, 2020-2023

This thesis documents a new approach to assess the aerodynamics of complex fluid dynamic systems using modern assessment methods associated with computational fluid dynamics (CFD). The method is developed to extract novel and additional insight in the context of a higher-fidelity modeling tool. Although the methods are based on classical control volume techniques balancing fluid momentum and energy, the approach uses the detailed data provided by CFD to expand on it. Classical methods typically use a fixing control volume defined at simple control surfaces, whereas this assessment method utilizes CFD to provide complex integrals on the control surfaces and uses …


A Monolithic Solid-State Interferometer For Real-Time Multi-Environment Measurements, Aaron J. Pung Jan 2022

A Monolithic Solid-State Interferometer For Real-Time Multi-Environment Measurements, Aaron J. Pung

Space Dynamics Laboratory Publications

The high degree of precision offered by optical interferometry makes it an ideal tool in many applications, including vibration detection, wind tunnel aerodynamics, surface topology measurements, and environmental sensing. In the latter case, real-time measurement of real-world environments is crucial to ensuring the health and safety of individuals operating within domestic and industrial domains. Currently, these measurements are made possible with portable fiber-based interferometer systems – systems that are also limited by high cost, fragility, coupling loss, and low power. This work presents a lightweight free-space interferometer that is versatile, modular, and compact. The interferometer is monolithic, geometrically simple, easy …


Integrating Experimental Parameter Space For Granular Flow Within Polygon Tumblers, Michaela Mcmahon Jan 2022

Integrating Experimental Parameter Space For Granular Flow Within Polygon Tumblers, Michaela Mcmahon

Graduate Research Theses & Dissertations

Granular flows are complex phenomena bridging both fluid and solid mechanics and observed frequently in the natural world. The transitional dynamics of acceleration from solid body motion to rapid flow can affect many aspects including volume flow rates and mixing behaviors. In order to study the combination of both variables together within polygon-shaped tumblers, control systems are necessary with a corresponding user interface. This thesis reports an interface for changing variable inputs to the system. Predictions of rotation rates with corresponding interfaces with hardware connections are described. Results of image analysis verify output performance that incorporates the following variable changes: …


Experimental Analysis Of Flowing Layer Characteristics In Equilateral Triangular Tumblers For Quasi-2d Macro-Particle Flow, Jason Quinn Ostenburg Jan 2022

Experimental Analysis Of Flowing Layer Characteristics In Equilateral Triangular Tumblers For Quasi-2d Macro-Particle Flow, Jason Quinn Ostenburg

Graduate Research Theses & Dissertations

Rotating tumblers are used in a wide variety of industrial applications from mixing anddeburring to flow regulation and storage. Almost all model tumblers previously analyzed, both theoretically and experimentally, had circular cross sections that produced consistent flowing layer dimensions and steady state flow. In contrast, tumblers with triangular cross sections produced unsteady flow as a direct result of the dynamic dimensions of the flowing surface. Although unsteady, the flow produced in triangular tumblers is periodic every 120◦ of rotation after an initial mixing period. The mechanisms by which the flow characteristics vary as a triangular tumbler rotates and the number …


A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese Jan 2022

A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese

Electronic Theses and Dissertations

The scramjet engine equipped with a modern-day airliner would allow for very quick travel across the United States. The major problem is that designing such an engine and testing it to make sure it is safe would cost millions if not billions of dollars. Computational fluid dynamics allows for complex designs to be tested but can still take many days, weeks, or even months to complete. With the use of computational fluid dynamics (CFD), the scramjet engine can be analyzed to determine a quicker way to test and develop a reliable configuration in addition to analyzing the effects of different …


Aerodynamic Performance Of A Biologically Inspired Hybrid Plasma-Mechanical Flow Control And Sensing Device, Joseph Dygert Jan 2022

Aerodynamic Performance Of A Biologically Inspired Hybrid Plasma-Mechanical Flow Control And Sensing Device, Joseph Dygert

Graduate Theses, Dissertations, and Problem Reports (ETD)

The continued high global demand for passenger and freight air traffic along with increased use of unmanned aerial vehicles operating in broader Reynolds number regimes has resulted in researchers examining alternative technologies, which would result in safer, more reliable, and superior performing aircraft. Aerodynamic flow control may be one of the most promising approaches to solving this problem, having already proven its ability to enable higher flow efficiency while simultaneously improving overall control of flow behavior such as laminar-to-turbulent transition. Recent research in aerodynamic flow control has seen a pronounced growth in the areas of biomimicry and plasma flow control …


Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen Jan 2022

Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Unmanned Aerial Vehicles (UAVs), also known as drones, are often considered the solution to complex robotics problems. The significant freedom to explore an environment is a major reason why UAVs are a popular choice for automated solutions. UAVs, however, have a very limited flight time due to the low capacity and weight ratio of current batteries. One way to extend the vehicles' flight time is to use a tether to provide power from external batteries, generators on the ground, or another vehicle. Attaching a tether to a vehicle may constrain its navigation but it may also create some opportunities for …


Attainable Moment Set And Actuation Time Of A Bio-Inspired Rotating Empennage, Christian R. Bolander, Douglas F. Hunsaker, David Myszka, James J. Joo Jan 2022

Attainable Moment Set And Actuation Time Of A Bio-Inspired Rotating Empennage, Christian R. Bolander, Douglas F. Hunsaker, David Myszka, James J. Joo

Mechanical and Aerospace Engineering Faculty Publications

Future tactical aircraft will likely demonstrate improvements in efficiency, weight, and control by implementing bio-inspired control systems. This work analyzes a novel control system for a fighter aircraft inspired by the function of – and the degrees of freedom available in – a bird’s tail. The control system is introduced to an existing fighter aircraft design by removing the vertical tail and allowing the horizontal tail surfaces to rotate about the roll axis. Using a low-fidelity aerodynamic model, an analysis on the available controlling moments and actuation speeds of the baseline aircraft is compared to that of the bio-inspired rotating …


Strategies To Reduce Nonconformance Of Parts In Aerospace Manufacturing, John Louis Lloyd Jr Jan 2022

Strategies To Reduce Nonconformance Of Parts In Aerospace Manufacturing, John Louis Lloyd Jr

Walden Dissertations and Doctoral Studies

The cost of nonconformance of parts can impact the aerospace industry globally, resulting in revenue loss and consumer confidence degradation. Grounded in the eight disciplines of problem solving, the purpose of this multiple case study was to explore strategies aerospace manufacturing quality managers in the United States used to implement successful change initiatives to address the nonconformance of parts. Data were collected through semistructured interviews with four aerospace quality executives and supporting company documents. Data were analyzed using methodological triangulation, coding, and thematic analysis. Four themes emerged: (a) identify and implement a specific problem-solving strategy, (b) identify and mitigate employee …


Concept Evaluation And Development Of A Novel Approach For Integration Of Turbogeneration, Electrification And Supercharging On Heavy Duty Engines, Satyum Joshi Jan 2022

Concept Evaluation And Development Of A Novel Approach For Integration Of Turbogeneration, Electrification And Supercharging On Heavy Duty Engines, Satyum Joshi

Dissertations, Master's Theses and Master's Reports

While many technologies such as electrically assisted turbocharging, exhaust energy recovery and mild hybridization have already proven to significantly increase heavy-duty engine efficiency, the key challenge to their widespread adoption has been their cost effectiveness and packaging. This research specifically addresses these challenges through evaluation and development of a novel technology concept termed as the Integrated Turbogeneration, Electrification and Supercharging (ITES) system. The concept integrates a secondary compressor, a turbocompound/expander turbine and an electric motor through a planetary gearset into the engine cranktrain. The approach enables a reduced system cost and space-claim, while maximizing the efficiency benefits of independent technologies. …


Calorimetric Measurements Of Lunar Regolith Simulant And Water. An Experimental Study Correlating Weight Percent Water And Temperature Change Through Periods Of Phase Change., George B. Johnson Jan 2022

Calorimetric Measurements Of Lunar Regolith Simulant And Water. An Experimental Study Correlating Weight Percent Water And Temperature Change Through Periods Of Phase Change., George B. Johnson

Dissertations, Master's Theses and Master's Reports

Permanently Shaded Regions (PSRs) are cold traps located around the lunar south pole that have been confirmed to contain possible interesting quantities or volatiles such as H2O, CO2, SO2, CH4, and others. [1] The identification of these volatiles on the lunar surface was a critical step in the development of NASA’s strategic goals for scientific discoveries, sustained space travel and exploration, and re-establishing a human presence on the moon. These volatiles are vital to the future of operating in and exploring space. The LCROSS impact revealed the existence of these resources in PSRs but more information is needed about the …


Mu2e Pion Degrader For Detector Calibration, Jessie Bouche Miles Jan 2022

Mu2e Pion Degrader For Detector Calibration, Jessie Bouche Miles

Graduate Research Theses & Dissertations

Particle tracking within the Mu2e experiment can be accomplished through regulating the rate of capture at the stopping target with the addition of a thin, low atomic weight material, the “degrader.” Investigation of Mu2e studies and simulations provide initial data for degrader design. The overall thickness of the degrader plus structural components must fit between the last two solenoids during operation and resist displacement. The degrader area, perpendicular to the beamline, must exceed that of the stopping target during alignment and be able to clear outer diameters of the beamline components. Structural analysis will ensure all dimensional constraints are met …


Probabilistic Space Weather Modeling And Forecasting For The Challenge Of Orbital Drag In Space Traffic Management, Richard J. Licata Iii Jan 2022

Probabilistic Space Weather Modeling And Forecasting For The Challenge Of Orbital Drag In Space Traffic Management, Richard J. Licata Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the modern space age, private companies are crowding the already-congested low Earth orbit (LEO) regime with small satellite mega constellations. With over 25,000 objects larger than 10 cm already in LEO, this rapid expansion is forcing us towards the enterprise on Space Traffic Management (STM). STM is an operational effort that focuses on conjunction assessment and collision avoidance between objects. While the equations of motion for objects in orbit are well-known, there are many uncertain parameters that result in the uncertainty of an object's future position. The force that the atmosphere exerts on satellite - known as drag - …


Evaluation Of Onboard Detect-And-Avoid System For Suas Bvlos Operations, Jon M. Loffi, Samuel M. Vance, Jamey Jacob, Luke Spaulding, Jared C. Dunlap Jan 2022

Evaluation Of Onboard Detect-And-Avoid System For Suas Bvlos Operations, Jon M. Loffi, Samuel M. Vance, Jamey Jacob, Luke Spaulding, Jared C. Dunlap

International Journal of Aviation, Aeronautics, and Aerospace

No abstract provided.


Self-Acquisition Of Liquid Propellant Versatile Arsenal Of Resources Endeavour (S.A.L.V.A.R.E.), Vittorio Baraldi, Nikki Smith-Cielo, Sotirios Zormpas Jan 2022

Self-Acquisition Of Liquid Propellant Versatile Arsenal Of Resources Endeavour (S.A.L.V.A.R.E.), Vittorio Baraldi, Nikki Smith-Cielo, Sotirios Zormpas

Student Works

Unlocking the mysteries of Mars’s past and future habitability is just within humanity’s grasp. With a multitude of inherent similarities to Earth, Mars is one of the most promising locations to extend humankind’s reach in manned space exploration. As humanity is at the summit of taking the next leap for mankind by preparing the first crewed missions to Mars, a need that must be met is to significantly reduce the mass necessary to deliver to the surface.

The Self-Acquisition of Liquid propellant Versatile Arsenal of Resources Endeavour (SALVARE) project details a mission for creating the first Mars water-based In-Situ Resources …


Development And Verification Of Flight Data Informed Performance Estimation And Prediction Simulation Tool For Small Electrical Multi-Rotor Uav, Nicholas Scott Borelle Jan 2022

Development And Verification Of Flight Data Informed Performance Estimation And Prediction Simulation Tool For Small Electrical Multi-Rotor Uav, Nicholas Scott Borelle

Graduate Theses, Dissertations, and Problem Reports (ETD)

While small scale multi-rotor aircraft are becoming an increasingly large market with applications emerging every day, their ability to have both a high endurance/long range and a high speed/performance flight is severely limited. This leads to uncertainty in mission planning and aircraft design, specifically when deciding mission length and available on-board energy. Uncertainty like this leads to an increased chance of failure to complete the mission, and a failure to recover the aircraft. Considering that these aircraft are used by everyone from hobbyists to commercial companies to military personnel, the applications and missions being flown carry importance and a serious …


The Utilization And Loss Of Available Energy In Aerospace Systems, Mohammad Abbas Jan 2022

The Utilization And Loss Of Available Energy In Aerospace Systems, Mohammad Abbas

Doctoral Dissertations

“Theoretical principles and analytical methodology for the control volume-based energy availability methodology for aerospace vehicles are developed; applications are made to jet-propelled and rocket-propelled vehicles as well as to stand-alone engine systems. Energy availability utilization characteristics of a modeled turbojet engine are studied across a wide range of operating conditions of throttle setting, flight altitude, and flight Mach number. The method is also extended to consider jet-powered vehicles. Fundamental principles regarding entropy generation and energy availability are developed, including directly linking entropy generation and maximum range and endurance of a powered aircraft. Theory and application of the energy utilization methodology …


Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan Jan 2022

Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan

College of Graduate Studies: Theses & Dissertations

In recent years the development of rocket engines has been mainly focused on improving the engine cycle and creating new fuels. Rocket nozzle design has not been changed since the late 1960s. Recent needs for reliable and reusable rockets, as well as advancements in additive manufacturing, have brought new interest into the aerospike nozzle concept. This nozzle is a type of altitude adjusting nozzle that is up to 90% more efficient than bell nozzles at low altitudes and spends up to 30% less fuel. Since the nozzle body is submerged in the hot exhaust gasses it is difficult to keep …


Plasma Spheroidization Of Gas-Atomized 304l Stainless Steel Powder For Laser Powder Bed Fusion Process, M. Hossein Sehhat, Austin T. Sutton, Chia-Hung Hung, Ben Brown, Ronald J. O'Malley, Jonghyun Park, Ming-Chuan Leu Jan 2022

Plasma Spheroidization Of Gas-Atomized 304l Stainless Steel Powder For Laser Powder Bed Fusion Process, M. Hossein Sehhat, Austin T. Sutton, Chia-Hung Hung, Ben Brown, Ronald J. O'Malley, Jonghyun Park, Ming-Chuan Leu

PSMRC Faculty Research

Particles of AISI 304L stainless steel powder were spheroidized by the induction plasma spheroidization process (TekSphero-15 spheroidization system) to assess the effects of the spheroidization process on powder and part properties. The morphology of both as-received and spheroidized powders was characterized by measuring particle size and shape distribution. The chemistry of powders was studied using inductively coupled plasma optical emission spectroscopy for evaluation of composing elements, and the powder’s microstructure was assessed by X-ray diffraction for phase identification and by electron backscattered diffraction patterns for crystallography characterization. The Revolution Powder Analyzer was used to quantify powder flowability. The mechanical properties …