Aerospace Engineering Commons^™

Numerical Study Of Owls’ Leading-Edge Serrations, Asif Shahriar Nafi

Electronic Theses and Dissertations

The silent flight ability of owls is often attributed to their unique wing morphology and its interaction with their wingbeat kinematics. Among these distinctive morphological features, leading-edge serrations stand out – these are rigid, miniature, hook-like patterns located at the leading edge of the primary feathers of their wings. It had been hypothesized that these leading-edge serrations serve as a passive flow control mechanism, influencing the aerodynamic performance and potentially affecting the boundary layer development over the wing, subsequently influencing wake flow dynamics. Despite being the subject of research spanning multiple decades, a consensus regarding the aerodynamic mechanisms underpinning owls’ …

Wearable Sensing System For Noninvasive Monitoring Of Intracranial Biofluid Shifts In Aerospace Applications., Jacob L Griffith, Kim Cluff, Grant M Downes, Brandon Eckerman, Subash Bhandari, Benjamin E Loflin, Ryan Becker, Fayez Alruwaili, Noor Mohammed

Henry M. Rowan College of Engineering Departmental Research

The alteration of the hydrostatic pressure gradient in the human body has been associated with changes in human physiology, including abnormal blood flow, syncope, and visual impairment. The focus of this study was to evaluate changes in the resonant frequency of a wearable electromagnetic resonant skin patch sensor during simulated physiological changes observed in aerospace applications. Simulated microgravity was induced in eight healthy human participants (n = 8), and the implementation of lower body negative pressure (LBNP) countermeasures was induced in four healthy human participants (n = 4). The average shift in resonant frequency was -13.76 ± 6.49 MHz for …

Skyqube: Developing Tools For Stem Education Focusing On Space System Engineering, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "SkyQube: Developing Tools for STEM Education Focusing on Space System Engineering" from January 11, 2023.

Computer Based Modeling For Tilt-Wing E-Vtol Propeller Performance, Ege Konuk, Drew Landman

College of Engineering & Technology (Batten) Posters

Recent decades have seen a rapid popularization of Urban Air Mobility (UAM) concepts. The new generation of designs presents a wide range of configurations and approaches to exploit the advantages of these vehicles that can be used in civil, commercial, and military applications. One of the more popular concepts is the tandem tilt-wing e-VTOL configuration. However, these types of VTOL configurations bring challenges for performance prediction during crucial parts of flight operations. The flight dynamics during transition regimes where the vehicle transitions from vertical to forward flight and vice versa is not fully understood. In this research, modified blade element …

Nasa Student Launch - Payload, Eli Kirk

All Undergraduate Projects

A team of mechanical engineering, physics, and computer science students from Central Washington University have constructed a fully functional subscale model rocket to be flown at the NASA Student Launch competition. The rocket’s payload was designed to open the nose cone and take a photo of the rocket’s surroundings after descending from the launch. Smaller parts were constructed through machining and 3D printing that will be added to the purchased major component, the linear actuator, in order to perform the required tasks. These tasks are signaled by an attached electronics board, which will receive an RF command remotely, execute code, …

Evaluation And Optimization Of Thermal Solutions In Air And Liquid Cooling Systems For Datacenters, Vibin Shalom Simon

Mechanical and Aerospace Engineering Dissertations - Archive

A data center is a specifically constructed establishment designed to accommodate computing, storage, and transmission equipment, thereby facilitating essential business operations spanning diverse sectors of the economy. This facility serves as the designated physical infrastructure for housing servers, networking components, and data storage systems. In the context of traditional data centers, a substantial portion of energy, specifically around 45% to 55%, is directed towards supporting information technology (IT) operations. Additionally, a considerable allocation, varying from 30% to 40%, is attributed to the facilitation of cooling processes. The scope of this dissertation study comprises nine distinct chapters, each contributing to addressing …

Non-Intrusive Reduced Order Model Formulation For Inverse Shape Design Including Deforming Meshes And Multiphysics Problems., Kapil Aryal

Mechanical and Aerospace Engineering Dissertations - Archive

Despite significant advancements in computer capabilities for numerical simulations, engineers continue to face limitations when dealing with large-scale full-order model(FOM) simulations. These simulations often necessitate repeated solves, such as those encountered in inverse design, real-time solution prediction, error quantification, and solver convergence, among others. To address these challenges, reduced order modeling (ROM) has emerged as a valuable approach. This thesis focuses on the development of an ROM framework that combines Proper Orthogonal Decomposition (POD) with machine learning techniques. This integrated approach is applied to a diverse range of heat transfer and fluid flow inverse design problems. POD constructs optimal sets …

Cooperative Manipulation And Formation Control Using Multiple Aerial Vehicles, Uluhan Cem Kaya

Mechanical and Aerospace Engineering Dissertations - Archive

Recent advancements in autonomous systems have significantly impacted both academia and industry, opening new research avenues. One of them is the collaboration of multiple systems to achieve a common goal, which is known as a cooperative system. In the lack of human intelligence, decision making and perception capabilities, uncrewed autonomous systems could mutually benefit from each other’s capabilities when they are deployed and utilized together. This research tackles the collaboration of group of uncrewed aerial systems (UASs) where the constraint on individual vehicles requires a varying level of coordination and cooperation. Such cooperation can be in the form of a …

Turbulent Shockwave/Boundary-Layer Interactions Generated By Sharp Swept Fins, Dustin Levi Otten

Mechanical and Aerospace Engineering Dissertations - Archive

The shock/turbulent boundary layer interaction (STBLI) generated by a sharp fin with a 60 deg leading edge sweep mounted above a flat plate at Mach 2.5 was studied numerically. Incipient separation due to this highly swept fin was determined by varying the fin angle to the incoming freestream. The effect of a small fin/plate gap on STBLI incipient separation was established. Sweeping the fin increases the deflection required for incipient separation as the sweep reduces the interaction strength. A gap causes flow leakage under the fin, further reducing the interaction strength on the windward side. The incipient angle of attack …

Experimental Study On Thermal Performance Of Metal Foam Heat Sinks In Single Phase Liquid Immersion Cooling, Manish Kumawat

Mechanical and Aerospace Engineering Theses - Archive

In 1965, Intel co-founder Gordon Moore made the observation that the transistor counts on a chip double with a frequency of approximately every two years. This development resulted in more compact and potent ICs. However, the amount of heat produced on a chip increased proportionally with the number of transistors. Later, in the early 2000s, Dennard Scaling broke down. Transistors became so small that leakage currents (unwanted currents that flow within the transistor) emerged as a significant issue, and they contributed substantially to power consumption and heat generation. These tightly packed transistors produced heat, which decreased their performance and shortened …

Jcati Carbon Fiber Recycler: Crusher System, Devin Riley

All Undergraduate Projects

With a substantial rise in Carbon Fiber use across all industries, the need for a way to recycle the waste has grown as well. A group of Mechanical Engineering Technology students at Central Washington University funded by the Joint Center for Aerospace Technology (JCATI) have created a machine to recycle waste wing trimmings from the Boeing company’s airplanes. This machine consists of 5 different sub-assemblies being the oven, crusher, gear train, conveyor, and shredder. The purpose of this project was to decrease the deflection in the crusher caused by bulging in the housing and movement of the bearings. To decrease …

The Numerical Study Of Aeroacoustics Performance Of Wings With Different Wavelength Leading-Edge Tubercles, Youjie Zhang

Honors Undergraduate Theses

The leading-edge tubercle is a type of airfoil modification that inspired by the humpback whale. It was found that the aerodynamic performance of the wing would increase compared to the wing without tubercles. In the past several years, a lot of numerical and experimental studies have been accomplished to explore this leading-edge modification. Besides the aerodynamic performance change, this research explores the aeroacoustics behavior of airfoils with leading-edge tubercles. A numerical study based on Computational Fluid Dynamics (CFD) is established, and simulations using Star CCM are accomplished based on reasonable set-ups. The airfoil chosen to create the wing is NACA …

Strengthening Urban Resilience: Understanding The Interdependencies Of Outer Space And Strategic Planning For Sustainable Smart Environments, Ulpia-Elena Botezatu, Olga Bucovetchi, Adrian V. Gheorghe, Radu D. Stanciu

Engineering Management & Systems Engineering Faculty Publications

The conventional approach to urban planning has predominantly focused on horizontal dimensions, disregarding the potential risks originating from outer space. This paper aims to initiate a discourse on the vertical dimension of cities, which is influenced by outer space, as an essential element of strategic urban planning. Through an examination of a highly disruptive incident in outer space involving a collision between the Iridium 33 and Cosmos 2251 satellites, this article elucidates the intricate interdependencies between urban areas and outer space infrastructure and services. Leveraging the principles of critical infrastructure protection, which bridge the urban and outer space domains, and …

Design Considerations And Imaging Setup For Liquid Fuel Droplet Detonation Wave Experiments, Nicolas Berube

Electronic Theses and Dissertations, 2020-2023

Initial results, design considerations, and experimental validation of a new detonation tube are presented to further improve detonation wave interaction research. The new structure consists of four independent portions: the deflagration to detonation initiation section, transition expansion section, operating test section, and dump section. The initiation, transition, and test sections are designed to operate within a temperature limit of 150°C and a maximum detonation pressure of 100 bar. The test section is comprised of interchangeable 155 cm stainless steel 316 plates assembled to create a 10x10 cm square hollow structure, sealed with longitudinal O-rings between plates and lateral O-rings between …

The Effect Of Wing Shape And Ground Proximity On Unsteady Fluid Dynamics During The Perching Maneuver., Dibya Raj Adhikari

Electronic Theses and Dissertations, 2020-2023

While landing, birds often perform a perching maneuver, which involves pitching their wings upwards while decelerating to a complete stop. By performing this perching maneuver, the birds can continue generating higher lift and drag force while slowing down, resulting in a smooth landing. The present study is motivated by the perching maneuver and aims to investigate two critical aspects of it. First, we want to explore how the proximity of the ground affects the unsteady forces and the flow field during the perching flight; and second, we want to analyze how a wing sweep influences a perching maneuver. To explore …

Determination Of Damage Initiation Mechanisms In Aerospace Alloys Due To Stress Corrosion Cracking Via In-Situ Microscale Characterization Techniques, Remelisa Esteves

Electronic Theses and Dissertations, 2020-2023

Aluminum alloys are used on aerospace vehicles due to their high strength-to-weight ratio, formability and machinability. However, they become vulnerable to stress corrosion cracking (SCC) during their service life. SCC is primarily caused by the material's stress condition, a suitable corrosive environment and material susceptibility. It is also influenced by a mixture of electrochemical, mechanical, and chemical factors. Due to the complexity of SCC, tools with better resolution and sensitivity are needed to better understand the impact and interaction of the contributing factors. A vast amount of research has been done to study SCC behavior, but the scale of characterization …

Method-Of-Characteristics Models For Flowfield Evaluation Of Hypervelocity Test Facilities, Ananthkumar Jayamani

Mechanical and Aerospace Engineering Dissertations - Archive

Ground test facilities are an imperative part of the design and development of flying vehicles. In the case of high-enthalpy facilities, evaluating the gasdynamic and thermochemical state of the test gas poses challenges due to high temperature effects. This study aims to contribute to the development impulse facilities by developing reduced-order models resolving the flowfields of such facilities. Developed as a part of this study are various method-of-characteristics (MoC) algorithms which consider gases under varying levels of thermochemical complexity. The algorithms span from simple calorically perfect gases to full thermochemical nonequilibrium. The first set of algorithms was limited to unsteady …

Microstructural Finite Element Modeling Of High-Performance Carbon Fiber-Reinforced Composites To Characterize Microscale Material Properties And Fiber-Direction Compressive Strength, Quy Tung Ling Vu

Mechanical and Aerospace Engineering Dissertations - Archive

Carbon fiber-reinforced composites are increasingly used in aerospace application thanks to their excellent specific stiffness and strength. However, incomplete understanding of their failure behaviors leads to composite components often being designed with a high Safety Factor, limiting their advantages. Using computational methods, this project studies carbon fiber-reinforced composite microstructures for the objective of understanding and improving material performances under compression load which is one of the main considerations in primary aerospace structure design. A Finite Element (FE) model for the evaluation of composite compression behaviors was developed, allowing the identification of several key material properties affecting composite performance. The numerical …

Cooperative Rendezvous In Multi-Vehicle Systems, Rajeev Shobhit Voleti

Mechanical and Aerospace Engineering Dissertations - Archive

The field of cooperative, multi-vehicle systems has witnessed a significant expansion and evolution, yielding considerable opportunities for improved autonomy, resilience, and robustness. Despite these promising developments, complex challenges persist in ensuring secure and efficient rendezvous among cooperative peers. The term "rendezvous," within the realm of cooperative control, refers to the simultaneous convergence of multi-vehicle systems to a designated target location. In missile guidance, the problem of multiple pursuer missiles achieving rendezvous with a target is termed as a salvo attack. Current methodologies often grapple with issues related to synchronization, high latency and network security, all of which can adversely impact …

A Rigid Body Framework For Modeling And Simulation Of Formation Of Autonomous Agents, Suguru Sato

Mechanical and Aerospace Engineering Theses - Archive

Formation motion, wherein multiple agents operate within close proximity while maintaining precise relative positions and coordinated movements has a significant impact in the realm of Uncrewed Aerial Systems (UAS). Formation establishment, and station-keeping have been critical research areas as several missions can be conceived, and accomplished by groups of “simple” autonomous agents. Advances in this research have led to multiple advantages in areas such as reconnaissance, aerospace exploration, map building, search and rescue, etc. particularly, if the formation motion is inspired by nature and natural phenomena such as flock of birds, school of fish, hydrodynamics (smooth streamlines), magnetic fields, and …

Advances In Thermal Technologies Using Pyrolytic Graphite Sheet, Matt Ralphs, Matt Sinfield, Holly Mortensen, Matt Felt

Space Dynamics Laboratory Publications

Pyrolytic Graphite Sheets (PGS) have increased the achievable mass specific conductance of many critical, passive thermal technologies over the last several years. From thermal straps and cryocooler brackets to PGS-embedded conductor bars and honeycomb radiators, PGS is the answer to dissipating the ever-increasing heat loads in today’s cutting-edge spacecraft. This work outlines the advances in PGS thermal straps, PGS-embedded cryocooler brackets, PGS-embedded conductor bars, and PGS-embedded radiators (both machined and honeycomb) at Space Dynamics Laboratory (SDL). The capabilities of each PGS technology are compared to traditional thermal solutions (e.g., metallic thermal straps, conductor bars, and cryocooler brackets and heat pipe …

Characterizing Air Plasma Sprayed Aluminum Oxide Coatings For The Protection Of Structures In Lunar Environments, Perla Latorre Suarez

Electronic Theses and Dissertations, 2020-2023

Wear-resistant ceramic and ceramic composite coatings are significant to provide durability and support long-duration missions to the moon's surface for rovers, landers, robotic systems, habitats, and many other components. On the Lunar surface, structural components are continuously exposed to lunar dust projectiles that can cause protective coating delamination around the affected area, of protective coatings and this may not be physically visible. Ceramic coatings, composed of alumina, present excellent resistance to different types of wear due to their high strength and hardness as well as the ability to protect structural components from regolith impacts, wear, and abrasive damage. Air Plasma …

A Framework For The Automatic Identification Of Optimized Yield Surface Parameters, Kevin Hanekom

Honors Undergraduate Theses

Advanced engineering materials are designed to display tensile-compressive asymmetry (TCA) and anisotropy to provide unique attributes to critical components necessary in the hot section of turbines. The never-ending chase for higher efficiencies, and with them, higher temperature gradients, intrinsically leads to more and more of these complex materials, like single crystal turbine blades, embedded within the turbine environment. Mathematical models, known as yield criteria, allow engineers to visualize the mechanical behavior of these materials in various orientations under complex loading. Yield criteria are dependent on three key items in determination of their governing parameters: material test data, mathematical constraints, and …

An Evaluation Of Thermocouple Reconstruction Techniques, Derek Brauneis

Electronic Theses and Dissertations, 2020-2023

Temperature measurements can be difficult to obtain across many different harsh environments such as engine combustion chambers, engine exhaust temperatures, and explosion fireballs. While there are alternate methods to measure fluid temperature such as laser measurements, acoustic measurements, and camera imaging techniques, these methods can often be expensive, difficult to implement, and not able to see within the environment. Thermocouples are popular sensors because they are cheap and easy to implement across a wide range of applications and can measure temperature in areas where other methods cannot reach or see. However, while these sensors are very popular and versatile, they …

The Impacts Of Advanced Avionics On Degraded Visual Environments, Sultan Naseeb Harib Fairouz Mubarak, Anju Anna Jacob Dr

International Journal of Aviation, Aeronautics, and Aerospace

Degraded visual environments (DVE) such as brownout, sand storms, and night conditions are responsible for accidents and hence losses in the aviation industry. There is a need to develop avionic systems to support pilots when they encounter environmental conditions that compromise their visual capacity. This report discusses the effects of DVEs on aviation, expounds on the advanced avionic systems available and further elaborates how these systems are implemented in countering DVE conditions. The report recommends on how advanced avionics systems have been and are being implemented in aircrafts to support decisions made by pilots flying under degraded visual environments.

Accuracy Assessment Of The Ebee Using Rtk And Ppk Corrections Methods As A Function Of Distance To A Gnss Base Station, Joseph Cerreta, David Thirtyacre, Peter Miller, Scott S. Burgess, William J. Austin

International Journal of Aviation, Aeronautics, and Aerospace

The use of unmanned aircraft systems to collect data for photogrammetry models has grown significantly in recent years. The accuracy of a photogrammetric model can depend on image georeferencing. The distance from a reference base station can affect the accuracy of the results. Positioning corrections data relies on precise timing measurements of satellite signals. The signals travel through the Earth's atmosphere, which introduces errors due to ionospheric and tropospheric delays. The aim of this research was to examine the eBee X and its global GNSS accuracy by comparing the RTK and PPK methods at different base station distances in photogrammetry …

Stochastic Optimization To Reduce Aircraft Taxi-In Time At Igia, New Delhi, Rajib Das, Saileswar Ghosh, Rajendra Desai, Pijus Kanti Bhuin, Stuti Agarwal

International Journal of Aviation, Aeronautics, and Aerospace

Since there is an uncertainty in the arrival times of flights, pre-scheduled allocation of runways and stands and the subsequent first-come-first-served treatment results in a sub-optimal allocation of runways and stands, this is the prime reason for the unusual delays in taxi-in times at IGIA, New Delhi.

We simulated the arrival pattern of aircraft and utilized stochastic optimization to arrive at the best runway-stands allocation for a day. Optimization is done using a GRG Non-Linear algorithm in the Frontline Systems Analytic Solver platform. We applied this model to eight representative scenarios of two different days. Our results show that without …

Critical Space Infrastructure: A Complex System Governance Perspective, Adrian V. Gheorghe, James C. Pyne, Joseph Sisti, Charles B. Keating, Polinpapilinho F. Katina, William Edmonson

Engineering Management & Systems Engineering Faculty Publications

This paper examines the applicability of Complex System Governance (CSG) to advance the Critical Space Infrastructure field (CSI). CSI encompasses space related hardware, workforce, environment, facilities, and businesses that are necessary for societal well-being. CSI is increasing in importance as more societal serving systems are becoming dependent on CSI to operate. Given this increasing dependence on CSI, societal sectors are increasingly at risk should something go wrong with CSI upon which they depend. CSI has been developing is a fragmented way and lacks coherent organization. CSG is focused on design, execution, and evolution of system functions that provide for communications, …

Simplified Mass And Inertial Estimates For Aircraft With Components Of Constant Density, Benjamin C. Moulton, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

Aircraft mass and inertial properties are required for predicting the dynamics and handling qualities of aircraft. However, such properties can be difficult to estimate since these depend on the external shape and internal structure, systems, and mass distributions within the airframe. Mass and inertial properties of aircraft are often predicted using computer-aided design software, or measured using various experimental techniques. The present paper presents a method for quickly predicting the mass and inertial properties of complete aircraft consisting of components of constant density. Although the assumption of constant density may appear limiting, the method presented in this paper can be …

Auto-Ignition Characteristics Of Hydrogen Enriched Natural Gas For Gas Turbine Applications, Christopher T. Loving

Graduate Thesis and Dissertation 2023-2024

A successful transition to clean energy hinges on meeting the world's growing energy demand while reducing greenhouse gas emissions. Achieving this will require significant growth in electricity generation from clean and carbon-free energy sources. Several energy providers have already begun the transition from traditional carbon-based fuels to cleaner alternatives, such as hydrogen and hydrogen enriched natural gas. However, there are still many technical challenges that must be addressed when applying these fuels in gas turbines. The application of hydrogen or hydrogen/natural gas blends to advanced class gas turbines, which have higher operating pressures and temperatures has raised concerns about the …