Aerospace Engineering Commons^™

Experimental Investigation Of Mixtures Of 1-Ethyl-3-Methylimidazolium Ethyl Sulfate And Ethylammonium Nitrate With Electrospray Propulsion Applications, Mitchell J. Wainwright, Joshua L. Rovey, Shawn W. Miller, Benjamin D. Prince

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Physical properties, performance metrics, and mass spectra of mixtures of two ionic liquids (1-ethyl-3-methylimidazolium ethyl-sulfate aka [Emim][EtSO4] and ethyl ammonium nitrate aka EAN) are investigated from the standpoint of electrospray propulsive characteristics. Spectra suggest that as the [Emim][EtSO4] mixture fraction increases, the intensity of [Emim][EtSO4] related species in the plume also increases, while the presence of EAN decreases. Spectra also show presence of both EAN proton transfer species and species related to chemical reaction of [EtSO4] and water. Despite the volatility of EAN, it emits stably into vacuum at low flow rates when mixed with 25% [Emim][EtSO4]. Spectra also show …

Influence Of A Backward-Facing Step On Swept-Wing Boundary-Layer Transition, Jenna L. Eppink, Richard W. Wlezien, Rudolph A. King, Meelan Choudhari

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Experimental measurements were performed on a swept flat-plate model with an airfoil leading edge and imposed chordwise pressure gradient to determine the effects of a backward-facing step on transition in a low-speed stationary crossflow-dominated boundary layer. Detailed hot-wire measurements were performed for three step heights ranging from 36 to 49% of the boundary-layer thickness at the step and corresponding to subcritical, nearly critical, and critical cases. In general, the step had a small, localized effect on the growth of the stationary crossflow vortex, whereas the unsteady disturbance amplitudes increased with increasing step height. Intermittent spikes in instantaneous velocity began to …

Improving Solder Joints Formed In Microgravity By Use Of Magnetic Soldering Paste Additives, Aaron Dunkle

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the expansion of the space industry, the need for the capability to repair electronics in space grows. Previous researchers have found that soldering in microgravity has yielded joints of poorer quality than those made on Earth, with increased interior porosity. WVU’s microgravity research team (MRT) constructed an experiment to solder onboard a microgravity aircraft to explore this problem and to test a possible solution. MRT’s experiment collected solder samples both in microgravity and a ground test, which were then cross-sectioned to allow the interior porosity of the joints to be studied. This determined that there was an increase in …

Artificial Immune System For Unmanned Aerial Vehicle Abnormal Condition Detection And Identification, Ryan G. Mclaughlin

Graduate Theses, Dissertations, and Problem Reports (ETD)

A detection and identification scheme for abnormal conditions was developed for an unmanned aerial vehicle (UAV) based on the artificial immune system (AIS) paradigm. This technique involves establishing a body of data to represent normal conditions referred to as “self” and differentiating these conditions from abnormal conditions, referred to as “non-self”. Data collected from simulation of the UAV attempting to autonomously fly a pre-decided trajectory were used to develop and test a scheme that was able to detect and identify aircraft sensor and actuator faults. These faults included aerodynamic control surface locks and damages and angular rate sensor biases. The …

Immunity-Based Framework For Autonomous Flight In Gps-Challenged Environment, Mohanad Al Nuaimi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, the artificial immune system (AIS) paradigm is used for the development of a conceptual framework for autonomous flight when vehicle position and velocity are not available from direct sources such as the global navigation satellite systems or external landmarks and systems. The AIS is expected to provide corrections of velocity and position estimations that are only based on the outputs of onboard inertial measurement units (IMU). The AIS comprises sets of artificial memory cells that simulate the function of memory T- and B-cells in the biological immune system of vertebrates. The innate immune system uses information about …

Mathematical Programming Approach For The Design Of Satellite Power Systems, Allen Flath Iii

Theses and Dissertations--Electrical and Computer Engineering

Satellite power systems can be understood as islanded dc microgrids supplied by specialized and coordinated solar cell arrays augmented by electrochemical battery systems to handle high-power loads and periods of eclipse. The periodic availability of power, the limited capacity of batteries, and the dependence of all mission service on power consumption create a unique situation in which temporal power and energy scarcity exist. A multi-period model of an orbital satellite power system’s performance over a mission’s duration can be constructed. A modular power system architecture is used to characterize the system’s constraints. Using mathematical programming, an optimization problem can be …

Landing-Gear Impact Response: A Non-Linear Finite Element Approach, Tuan H. Tran

UNF Graduate Theses and Dissertations

The primary objective of this research is to formulate a methodology of assessing the maximum impact loading condition that will incur onto an aircraft’s landing gear system via Finite Element Analysis (FEA) and appropriately determining its corresponding structural and impact responses to minimize potential design failures during hard landing (abnormal impact) and shock absorption testing. Both static and dynamic loading condition were closely analyzed, compared, and derived through the Federal Aviation Administration’s (FAA) airworthiness regulations and empirical testing data.

In this research, a nonlinear transient dynamic analysis is developed and established via NASTRAN advanced nonlinear finite element model (FEM) to …

Laser Machining Countersinks In Carbon Fiber Reinforced Polymer, Leon James Neely Hill

Masters Theses

“Laser machining countersinks with a frequency doubled Q-switched diode pumped Nd:YAG laser is demonstrated. Tests were conducted in 0.100" thick IM7 prepreg CFRP with [0,90]3S orientation. The HAZ is minimized to avoid stress concentrations in the epoxy matrix. A chamber and filtration system was designed and built to contain the byproducts produced in the machining process. The variables investigated are the number of repetitions in the offset path, the plunge rate, and the line energy. The research was performed over one baseline study, one parameter space exercise, two full factorial experiments, and one repeatability study. Assessment was done under an …

Propagation Of Uncertainty Through Coning, Sculling, And Scrolling Corrections For Inertial Navigation, James Daniel Alan Brouk

Masters Theses

"This thesis investigates the propagation of estimation errors through generalized coning, sculling, and scrolling algorithms used in modern day inertial navigation systems, in order to accurately quantify the uncertainty in the estimation of position, velocity, and attitude. The corrections for coning, sculling, and scrolling algorithms have an often unaccounted for effect on documented and empirically derived error statistics for measurements used to predict the uncertainty in a vehicle's position, velocity, and attitude estimates. Through the development of an error analysis for these generalized algorithms, mappings of the measurement and estimation errors through the correction termare generated. Using the developed mappings, …

Steady Flows In Annular Wedge Lid-Driven Cavities, Anandan Ganapathy

Graduate Research Theses & Dissertations

The lid-driven cavity is a well-known canonical problem in the field of analytical and computational fluid dynamics. It is comprised of a square domain of an incompressible fluid with its upper lid has a specified velocity and the remaining wall boundaries are subjected to fixed, no-slip, zero-velocity constraints. There are numerous examples found in the literature that address the well-known, stable behavior of this system, which includes a primary recirculating vortex, secondary corner vortices, and a velocity profile through the center midpoint y-axis that is shown to be dependent on the Reynolds number. In this investigation, the shape of the …

A Computational Fluid Dynamics Analysis Of The Aerodynamic Performance Of Wind Turbine, Ashkan Ostovari

Graduate Research Theses & Dissertations

Renewable energy resources are likely to be a future energy solution. Among them, the wind has gained a lot of interest. Despite the theoretical limitation in wind energy harnessing efficiency, it is, still, one of the most promising renewable resources with utilizing turbines to extract this energy. Wind turbines, based on their axis of rotation are categorized into vertical axis wind turbine (VAWT) and horizontal axis wind turbine (HAWT), which HAWT’s have shown relatively higher efficiency than VAWT’s. The aim of this thesis is first to develop a scaled-down model of a wind turbine in Computational Fluid Dynamics (CFD) environment …

Small Satellite Development At Utep, Emily Herzog

Open Access Theses & Dissertations

The small satellite industry has seen tremendous growth in recent years. A CubeSat is a particular type of standardized small satellite that follows the CubeSat specifications. These specifications define the structural, testing, and operational requirements of the satellite. This standard facilitates cheaper design, integration, and launch of satellites, allowing smaller organizations to participate in the normally costly area of space exploration.

The University of Texas at El Paso has recognized the opportunity and has begun developing several CubeSats. The two that are the topic of this Thesis are called Orbital Factory II (OFII) and Orbital Factory X (OFX). An on-orbit …

Structures And Daq System For The Lox/Lch4 500 And 2000 Lbf. Rocket Engines, Rachel Pilgrim

Open Access Theses & Dissertations

With the progression of space exploration and research, new alternative fuels and fuel combinations have been discovered. The ability to produce methane from Mars' atmosphere and oxygen from Mars' regolith has led to the two becoming a great alternative propellant combination for rocket propulsion systems. To further advance LOX/LCH4 propulsion systems, a 500 and 2000 lbf rocket engine were designed and manufactured and are to be launched from the MIRO cSETR Technology Research and Innovation Acceleration Park (tRIAc) in Fabens, Texas for data collection and analysis. The objective of this thesis is to give a thorough overview of the static …

Thermal/Mechanical Analysis And Development Of A 2000 Lbf Liquid Oxygen/Liquid Methane Rocket Engine, Marissa Garcia

Open Access Theses & Dissertations

The Center for Space Exploration and Technology Research (cSETR) is developing three rocket engines: a 5 lbf reaction control engine, a 500 lbf engine, and a 2000 lbf engine. All these engines utilize a liquid oxygen and liquid methane propellant combination. The reason methane was selected for the fuel is because methane is easy to store, is self-pressurizing, and readily available. There is also the possibility of creating methane on planets such as Mars through an electrolysis process on the ice water found on Mars.

The 2000 lbf engine, or the CROME-X, is a modular, steady-state pintle injector engine. It …

Investigating Using Titanium Zirconium Molybdenum For Additively Manufacturing Aerospace Components, Justin Hunter Vanhoose

Open Access Theses & Dissertations

Mankind throughout history has possessed an innate characteristic to explore, migrating to new frontiers.The requirement for this travel is most broadly associated with the need to pursue more resources. Rockets have been used as a means of weapons since the Sung Dynasty in the thirteenth empire and have now been integrated for travel/transport. The sophistication of rocketry and propulsion has reached a level to where it is plausible that mankind will be a multi-planetary species. The space industry has grown significantly with the advancement of the sophistication of these rocket technologies. However, a specific challenge to overcome in the space …

Structural Design Of Complex Components, Armando Antonio Ochoa

Open Access Theses & Dissertations

The University of Texas at El Paso (UTEP) and the Center for Space Exploration and Technology Research (cSETR) is determined to develop a launch vehicle that is made completely of additive manufacturing materials, has the capability to transport a 100 lb payload to low earth orbit (LEO) as well as completing the design of a strucutral steel mobile launch stand that has the capability of withstanding the launch vehicle's static and dynamic loadings. The project will consist of carbon composite components to reduce weight while maintaining efficiency, strucutral steel components to resist extreme loadings and maintain strucutral shape, and lastly …

Ultrafine Aluminium: Quench Collection Of Agglomerates, Tejasvi K, Y Pydi Setty, Vemana Venkateswara Rao

International Journal of Aviation, Aeronautics, and Aerospace

Combustion of aluminized solid propellants exhibits phenomena associated with accumulation, agglomeration, ignition, and combustion of ultra-fine aluminium particles. In this study, agglomeration phenomenon of ultra-fine aluminium in solid propellant combustion is investigated using quench collection experimental technique over the pressure ranges from 2MPa to 8MPa. The ultra-fine aluminium powder synthesized by Radio Frequency Induction Plasma technique having harmonic mean size of 438nm is used for agglomeration study. The quenching distance is varied from 5mm to 71mm from the propellant burning surface to estimate the effect on agglomerate size. The morphology and chemical compositions of the collected products were then studied …

Strategies In Developing An Aviation & Aerospace Skill Ecosystem For The State Of Telangana, India – Case Study Of Task -Telangana Academy For Skill And Knowledge, Kim Chua, Sujiv Nair, M.P Ganesh Dr.

International Journal of Aviation, Aeronautics, and Aerospace

The aviation & aerospace sector in India has been expanding and growing through partnerships and new research facilities, thereby encouraging more players to invest and optimize the manufacturing process. Improving green and fuel-efficient technologies have contributed to a steady rise in fuelling the demand for aerospace engineers.

The state of Telangana is fast emerging as a new aviation cluster with some of the country’s best-qualified engineers and technicians. The potential of the aerospace industry is immense as it continuously requires skilled technicians and engineers. Considering the precision of skill required, it is imperative that rigorous training be imparted to all …

Satellite Maintenance: An Opportunity To Minimize The Kessler Effect, Bettina M. Mrusek Dr.

International Journal of Aviation, Aeronautics, and Aerospace

Recently, there has been an emphasis on the growing problem of orbital debris. While the advantages of placing satellites into space are numerous, advances in satellite technology combined with the growth of the industry have resulted with a significant amount of debris in the orbits surrounding our planet. The harshness of the space environment has also contributed to the debris, as evidenced by the number of objects currently in orbit which are not operational. As the amount of debris grows, so too does the likelihood of collisions, ultimately culminating in the Kessler Effect. However, recent advances in propulsion, advanced navigation, …

Big Five Technologies In Aeronautical Engineering Education: Scoping Review, Ruth Martinez-Lopez

International Journal of Aviation, Aeronautics, and Aerospace

The constant demands that technology creates in aerospace engineering also influence education. The identification of the technologies with practical application in aerospace engineering is of current interest to decision makers in both universities and industry. A social network approach enhances this scoping review of the research literature to identify the main topics using the Big Five technologies in aerospace engineering education. The conceptual structure of the dataset (n=447) was analyzed from different approaches: at macro-level, a comparative of the digital technology identified by cluster analysis with the number of co-words established in 3 and 8 and, a keyword central structure …

Computational Study Of Flow Interactions Over A Close Coupled Canard-Wing On Fighter, Setyawan Bekti Wibowo, Sutrisno Sutrisno, Tri Agung Rohmat

International Journal of Aviation, Aeronautics, and Aerospace

There have been many attempts to improve the flying performance of a fighter. By modifying the flow that occurs along the fuselage is expected to improve the performance of the aircraft. One of the indicators of combat aircraft performance is the ability to perform maneuver movement. Adding a canard as forewing on the fighter wing configuration is considered capable of raising the ability in maneuver movement. The use of canard-delta pairs will affect the performance and aerodynamic characteristics of the plane. Wings and canards with delta configuration will make the rolled-up vortex as a lifting force producer on the aircraft. …

Urban Flow And Small Unmanned Aerial System Operations In The Built Environment, Kevin A. Adkins

International Journal of Aviation, Aeronautics, and Aerospace

The Federal Aviation Administration (FAA) has put forth a set of regulations (Part 107) that govern small unmanned aerial system (sUAS) operations. These regulations restrict unmanned aircraft (UA) from flying over people and their operation to within visual line of sight (VLOS). However, as new applications for unmanned aerial systems (UAS) are discovered, their capabilities improve, and regulations evolve, there is an increasing desire to undertake urban operations, such as urban air mobility, package delivery, infrastructure inspection, and surveillance. This built environment poses new weather hazards that include enhanced wind shear and turbulence. The smaller physical dimensions, lower mass and …

Aerodynamic Design And Exploration Of A Blended Wing Body Aircraft At Subsonic Speed, Sam Dakka Dr, Oliver Johnson

International Journal of Aviation, Aeronautics, and Aerospace

Blended Wing Body (BWB) is a novel aircraft concept which provides many different aerodynamic benefits over conventional aircrafts design. This research investigated the BWB design, L/D characteristics, surface pressure distribution and span-wise lift distribution of a BWB aircraft at low to medium subsonic speeds. A BWB model was designed, manufactured and tested in a subsonic wind tunnel to validate the CFD simulation. The results gained from the investigation proved that BWB has a L/D improvement of 9.4% than conventional aircrafts and 21% increase at medium subsonic speeds (Mach 0.6) compared to lower subsonic speeds of 25 m/sec. It was found …

A New Method For The Prediction Of The Downwash Angle Gradient, Mondher Yahyaoui Dr.

International Journal of Aviation, Aeronautics, and Aerospace

A new method for the prediction of the downwash angle gradient due to aircraft wings across the span of an aft horizontal tail in the incompressible regime is presented. The approach is quite general and accounts for all practical wing geometric parameters except for wing twist where it is shown that this parameter has very little effect on the downwash angle gradient. The method consists of an empirical law which requires the prior knowledge of three constants. These have been computed either based on experimental data when available or using numerical data obtained using the vortex-lattice method. These constants are …

Interlaminar Damage Detection In Composite Materials, Hariharan Rangarajan

Williams Honors College, Honors Research Projects

Using ceramic matrix composites (CMCs) for high-temperature applications in jet engines increases durability and reduces weight and cooling requirements resulting in improved efficiency and fuel savings. Understanding, detecting, and monitoring different types of damage is essential to achieve optimal performance of CMC components. The Direct Current Potential Drop (DCPD) method is a non-destructive technique of estimating damage in composite materials.

DCPD technique works by measuring nodal potential differences when current is flown through the material. Direct current spreading in different woven and laminate composites is modeled to follow a ladder resistor network in which the nodal voltages decrease exponentially as …

Uas Flight Operations In Complex Terrain: Assessing The Agricultural Impact From Hurricane Maria In The Central Mountainous Region Of Puerto Rico, Kevin Adkins

Publications

Hurricane Maria struck Puerto Rico in September 2017 as a Category 4 storm causing major damage to infrastructure, agriculture and natural ecosystems, as well as the loss of many lives. Among the crops hardest hit was coffee, one of the most important crops in Puerto Rico. As a perennial system, coffee takes various production forms along a gradient from high shade/biodiversity coffee farms to low shade coffee monocultures and therefore offers an ideal means for the study of resistance and resilience of an agroecosystem to weather and climate disturbance. During the summer of 2018, 14 impacted farms across the production …

Traditional Vs Gesture Based Uav Control, Sam J. Holley, Brian Sanders, Dennis Vincenzi, Yuzhong Shen

Publications

Abstract. The purpose of this investigation was to assess user preferences for controlling an autonomous system. A comparison using a virtual environment (VE) was made between a joystick based, game controller and a gesture-based system using the leap motion controller. Command functions included basic flight maneuvers and switching between the operator and drone view. Comparisons were made between the control approaches using a representative quadcopter drone. The VE was designed to minimize the cognitive loading and focus on the flight control. It is a physics-based flight simulator built in Unity3D. Participants first spend time familiarizing themselves with the basic controls …

Low Level Turbulence Detection For Airport, Derek Kearney, Anthony O'Connor

Articles

Low level wind shear and turbulence present a serious safety risk to aircraft during the approach, landing and take-off phases. Despite many advances in on-board and ground based warning systems. Wind shear remains a formidable force that coupled with a microburst can overpower any aircraft. Aviation reports have concluded that pilots need to have improved information in relation to tailwinds, wind shear and wind variations on approach and during the landing phases. Low level wind shear continues to cause disruption, delays and contribute to aircraft crashes. As recently as 2016, two Boeing aircraft crashed while attempting a Go-around manoeuver after …

On Hybrid Temporal Basis Functions For Stable Numerical Solution Of Time Domain Boundary Integral Equations, Fang Q. Hu

Mathematics & Statistics Faculty Publications

Problems in unsteady aerodynamics and aeroacoustics can sometimes be formulated as integral equations, such as the boundary integral equations. Numerical discretization of integral equations in the time domain often leads to so-called March-On-in-Time (MOT) schemes. In the literature, the temporal basis functions used in MOT schemes have been largely limited to low-order shifted Lagrange basis functions. In order to evaluate the accuracy and effectiveness of the temporal basis functions, a Fourier analysis of the temporal interpolation schemes is carried out. Based on the Fourier analysis, the spectral resolutions of various temporal basis functions are quantified. It is argued that hybrid …

Determine Airborne Release Fractions (Arf) / Respirable Fractions (Rf) For Use In Safety Based Documents, Michael Quinn, Jacob Miller

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.