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Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall 2018 Utah State University

Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall

All Graduate Theses and Dissertations

A thrust augmented nozzle for hybrid rocket systems is investigated. The design lever-ages 3-D additive manufacturing to embed a helical fuel port into the thrust chamber of a hybrid rocket burning gaseous oxygen and ABS plastic as propellants. The helical port significantly increases how quickly the fuel burns, resulting in a fuel-rich exhaust exiting the nozzle. When a secondary gaseous oxygen flow is injected into the nozzle downstream of the throat, all of the remaining unburned fuel in the plume spontaneously ignites. This secondary reaction produces additional high pressure gases that are captured by the nozzle and significantly increases the ...


Numerical Simulation Of Shock Wave Propagation In Ducts With Grooves, Seyed Mehdi Mortazawy 2018 Embry-Riddle Aeronautical University

Numerical Simulation Of Shock Wave Propagation In Ducts With Grooves, Seyed Mehdi Mortazawy

Dissertations and Theses

The pressure attenuation of moving shocks when they propagate in ducts, is of great importance in a wide variety of applications, such as health, safety, and transportation. The objective of this research is to simulate the propagation of shock waves in ducts with roughness. The roughness is added in the form of grooves as in an existing experiment. Different shapes are considered in order to better understand the physics behind the evolution of the complex shock patterns resulting from diffraction, reflection and refraction of the primary moving shock. The contribution of grooves and duct shape on these phenomena and pressure ...


A Novel Magnetorheological Fluid Damper For A Small Spacecraft With Flexible Appendages, Robert Waelchili 2018 Embry-Riddle Aeronautical University

A Novel Magnetorheological Fluid Damper For A Small Spacecraft With Flexible Appendages, Robert Waelchili

Dissertations and Theses

Small satellites have become increasingly popular over the past thirty years, particularly since the adoption of the common CubeSat architecture early this century. Because of their restricted volume and electrical budgets however, there are practical limits to the missions that small satellites may adopt. One potential near-term solution to the problem of limited electrical power may be the adoption of larger, flexible solar arrays. However, spacecraft with flexible appendages have historically presented attitude control challenges relating to platform stability given the dynamic response of the flexible components to applied torques. These challenges may be particularly disruptive to a small spacecraft ...


Vision-Aided Navigation Using Tracked Lankmarks, Nicodemus Myhre 2018 Embry-Riddle Aeronautical University

Vision-Aided Navigation Using Tracked Lankmarks, Nicodemus Myhre

Dissertations and Theses

This thesis presents vision-based state estimation algorithms for autonomous vehicles to navigate within GPS-denied environments. To accomplish this objective, an approach is developed that utilizes a priori information about the environment. In particular, the algorithm leverages recognizable ‘landmarks’ in the environment, the positions of which are known in advance, to stabilize the state estimate. Measurements of the position of one or more landmarks in the image plane of a monocular camera are then filtered using an extended Kalman filter (EKF) with data from a traditional inertial measurement unit (IMU) consisting of accelerometers and rate gyros to produce the state estimate ...


Additive Manufacturing Of High Solids Loading Hybrid Rocket Fuel Grains, Stephen P. Johnson 2018 Olivet Nazarene University

Additive Manufacturing Of High Solids Loading Hybrid Rocket Fuel Grains, Stephen P. Johnson

Scholar Week 2016 - present

Hybrid rocket motors offer many of the benefits of both liquid and solid rocket systems. Like liquid engines, hybrid rocket motors are able to be throttled, can be stopped and restarted, and are safer than solid rocket motors since the fuel and oxidizer are in different physical states. Hybrid rocket motors are similar to solid motors in that they are relatively simple and have a high density-specific impulse. One of the major drawbacks of hybrid rocket motors is a slower burning rate than solid rocket motors. Complex port geometries provide greater burning surface area to compensate for lower burning rates ...


Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohamed Aldeeb, Waqar Asrar, Erwin Sulaeman 2018 International Islamic University - Malaysia

Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohamed Aldeeb, Waqar Asrar, Erwin Sulaeman

International Journal of Aviation, Aeronautics, and Aerospace

Experiments on the relative merits and demerits of slotted wingtips mimicking a bird’s primary feathers have been performed. The real emargination length of feather tips, their flexibility and curved shapes during cruise are considered in the present study. The experiments were performed at a Reynolds number of 3.7 x 105 on a symmetric flat plate half wing of aspect ratio 3. Lift, drag and pitching moments were measured using a six component aerodynamic balance. Four different shapes inspired by bird primary feathers have been analysed. The rigid curved tip performed the best increasing the L/D ratio ...


Durability Assessment Of Soft Elastomeric Capacitor Skin For Shm Of Wind Turbine Blades, Austin Downey, Anna Laura Pisello, Elena Fortunati, Claudia Fabiani, Francesca Luzi, Luigi Torre, Filippo Ubertini, Simon Laflamme 2018 Iowa State University

Durability Assessment Of Soft Elastomeric Capacitor Skin For Shm Of Wind Turbine Blades, Austin Downey, Anna Laura Pisello, Elena Fortunati, Claudia Fabiani, Francesca Luzi, Luigi Torre, Filippo Ubertini, Simon Laflamme

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

Renewable energy production has become a key research driver during the last decade. Wind energy represents a ready technology for large-scale implementation in locations all around the world. While important research is conducted to optimize wind energy production efficiency, a critical issue consists of monitoring the structural integrity and functionality of these large structures during their operational life cycle. This paper investigates the durability of a soft elastomeric capacitor strain sensing membrane, designed for structural health monitoring of wind turbines, when exposed to aggressive environmental conditions. The sensor is a capacitor made of three thin layers of an SEBS polymer ...


The Challenges Of Processing Kite Aerial Photography Imagery With Modern Photogrammetry Techniques, Jeremy W. Aber, Tyler A. Babb 2018 Middle Tennessee State University

The Challenges Of Processing Kite Aerial Photography Imagery With Modern Photogrammetry Techniques, Jeremy W. Aber, Tyler A. Babb

International Journal of Aviation, Aeronautics, and Aerospace

Kite Aerial Photography (KAP) is a traditional method of collecting small-format aerial photography used for work in a variety of fields. This research explored techniques for processing KAP imagery with a focus on some of the challenges specific to photo processing. The performance of multiple automated image compositing programs was compared using a common set of 29 images. Those packages that were based on a photogrammetry approach outperformed the non-photogrammetric software, and generated similar levels of quality to one another. While all three photogrammetric packages produced satisfactory output, each had unique challenges.


Manufacturing Process Simulation – On Its Way To Industrial Application, Dennis Otten, Tobias A. Weber, Jan-Christoph Arent 2018 University of Applied Sciences Augsburg

Manufacturing Process Simulation – On Its Way To Industrial Application, Dennis Otten, Tobias A. Weber, Jan-Christoph Arent

International Journal of Aviation, Aeronautics, and Aerospace

Manufacturing process simulation (MPS) has become more and more important for aviation and the automobile industry. A highly competitive market requires the use of high performance metals and composite materials in combination with reduced manufacturing cost and time as well as a minimization of the time to market for a new product. However, the use of such materials is expensive and requires sophisticated manufacturing processes. An experience based process and tooling design followed by a lengthy trial-and-error optimization is just not contemporary anymore. Instead, a tooling design process aided by simulation is used more often. This paper provides an overview ...


The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2018, Buenaventura "Ven" Basco 2018 University of Central Florida

The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2018, Buenaventura "Ven" Basco

Libraries' Newsletters

No abstract provided.


Nonlinear Control Of Underactuated And Constrained Systems, Derek Hoffman 2018 Embry-Riddle Aeronautical University

Nonlinear Control Of Underactuated And Constrained Systems, Derek Hoffman

Dissertations and Theses

It is the purpose of this document to elaborate on the control of systems that are underactuated or otherwise constrained. To do so, local- and global-coordinate formulations are implemented to generate well-defined system dynamics for a multitude of scenarios. These dynamics are shown to lie on manifolds defined by mathematical restrictions, allowing for singularity-free modeling for global considerations. Feed-back controllers by extension share these benefits, facilitating singularity-free control algorithms as a result. Further, unactuated degrees of freedom can be treated as additional constraints, resulting in an embedded manifold upon the original dynamics. A transformation between a provided set of dynamical ...


Nanoindentation Study Of Corrosion-Induced Grain Boundary Degradation In A Pipeline Steel, Denizhan Yavas, Pratyush Mishra, Abdullah Alshehri, Pranav Shrotriya, Kurt R. Hebert, Ashraf F. Bastawros 2018 Iowa State University

Nanoindentation Study Of Corrosion-Induced Grain Boundary Degradation In A Pipeline Steel, Denizhan Yavas, Pratyush Mishra, Abdullah Alshehri, Pranav Shrotriya, Kurt R. Hebert, Ashraf F. Bastawros

Aerospace Engineering Publications

High-strength low-alloy steels used for oil and gas pipelines are vulnerable to intergranular stress corrosion cracking in moderately alkaline soils. The mechanism of corrosion-induced embrittlement under such conditions is not yet understood. Nanoindentation was used to detect localized degradation of mechanical properties near internal grain boundaries of X-70 steel undergoing intergranular corrosion at active dissolution potentials at pH 8.2. The measurements identified a one-micron thick mechanically-degraded layer with 25% reduced hardness near corroded grain boundaries. It is suggested that the corrosion process may introduce an active softening agent, possibly non-equilibrium lattice vacancies generated by oxidation.


Model-Assisted Approach For Probability Of Detection (Pod) In High-Temperature Ultrasonic Nde Using Low-Temperature Signals, Prathamesh N. Bilgunde, Leonard J. Bond 2018 Iowa State University

Model-Assisted Approach For Probability Of Detection (Pod) In High-Temperature Ultrasonic Nde Using Low-Temperature Signals, Prathamesh N. Bilgunde, Leonard J. Bond

Aerospace Engineering Publications

Advanced piezoelectric-based ultrasonic transducers offer the potential for in-coolant nondestructive testing (NDT) measurements at high temperatures (HTs), including during hot standby (~260°C) for liquid-sodium–cooled advanced small modular reactors. The reliability of the NDT measurements is typically quantified by the probability of detection (POD) measured at the corresponding temperature. Obtaining such data in liquid sodium is challenging. Using a model-assisted POD approach, a transfer function is reported that enables data obtained on low carbon steel specimens at room temperature to give an estimated POD at an HT. A primary source of the difference in POD between room temperature and ...


Les Taux De Rupture De Conduites D’Eau Aux États-Unis Et Au Canada : Une Étude Complète, Steven Folkman 2018 Utah State University

Les Taux De Rupture De Conduites D’Eau Aux États-Unis Et Au Canada : Une Étude Complète, Steven Folkman

Mechanical and Aerospace Engineering Faculty Publications

La prospérité économique des villes modernes est basée sur un réseau d’infrastructures complexe à la fois en surface et sous la terre. Un élément essentiel pour la santé publique et le bien-être économique est notre eau potable, qui est acheminée jusqu’à notre robinet à travers un réseau complexe de conduites de distribution d’eau souterraines. Étant donné que la plus grande partie de cette infrastructure se trouve sous terre, elle est hors de vue et souvent négligée. Disposer de données empiriques sur des ruptures de conduites d’eau aide les services publics avec leurs processus de prises de ...


Low Reynolds Number Numerical Simulation Of The Aerodynamic Coefficients Of A 3d Wing, Khurshid Malik, Waqar Asrar, Erwin Sulaeman 2018 International Islamic University - Malaysia

Low Reynolds Number Numerical Simulation Of The Aerodynamic Coefficients Of A 3d Wing, Khurshid Malik, Waqar Asrar, Erwin Sulaeman

International Journal of Aviation, Aeronautics, and Aerospace

A low Reynolds number, three-dimensional CFD analysis is carried out for a finite flat plate wing using the commercial CFD code STAR CCM+. The six-aerodynamic force and moment components CL, CD, CM, CN, Cl, CY and their derivatives are computed at a Reynolds numbers of 3x105 by varying the pitch, roll and yaw angles about the quarter chord point. The computed results have been validated with experimental aerodynamic balance data when possible. The results indicate that roll and yaw angle affect the aerodynamic coefficients of the flat plate wing along with the pitch ...


Magnetic Two-Way Valves For Paper-Based Capillary-Driven Microfluidic Devices, Mario Fratzl, Boyce Chang, Stephanie Oyola-Reynoso, Guillaume Blaire, Sarah Delshad, Thibaut Devillers, Thomas Ward, III, Nora M. Dempsey, Jean-Francis Bloch, Martin M. Thuo 2018 Université Grenoble Alpes

Magnetic Two-Way Valves For Paper-Based Capillary-Driven Microfluidic Devices, Mario Fratzl, Boyce Chang, Stephanie Oyola-Reynoso, Guillaume Blaire, Sarah Delshad, Thibaut Devillers, Thomas Ward, Iii, Nora M. Dempsey, Jean-Francis Bloch, Martin M. Thuo

Materials Science and Engineering Publications

This article presents a magnetically actuated two-way, three-position (+, 0, −), paper-based microfluidic valve that includes a neutral position (0)--the first of its kind. The system is highly robust, customizable, and fully automated. The advent of a neutral position and the ability to precisely control switching frequencies establish a new platform for highly controlled fluid flows in paper-based wicking microfluidic devices. The potential utility of these valves is demonstrated in automated, programmed, patterning of dyed liquids in a wicking device akin to a colorimetric assay but with a programmed fluid/reagent delivery. These valves are fabricated using facile methods and thus ...


Comparison Of Thermal Properties Of Laser Deposition And Traditional Welding Process Via Thermal Diffusivity Measurement, Yu Yang, Omoghene Osaze Obahor, Yaxin Bao, Todd E. Sparks, Jianzhong Ruan, Jacquelyn K. Stroble, Robert G. Landers, Joseph William Newkirk, Frank W. Liou 2018 Missouri University of Science and Technology

Comparison Of Thermal Properties Of Laser Deposition And Traditional Welding Process Via Thermal Diffusivity Measurement, Yu Yang, Omoghene Osaze Obahor, Yaxin Bao, Todd E. Sparks, Jianzhong Ruan, Jacquelyn K. Stroble, Robert G. Landers, Joseph William Newkirk, Frank W. Liou

Joseph William Newkirk

Laser deposition is an effective process for mold and die repair. In order to improve the part repair quality, the process impact on thermal diffusivity and thermal conductivity needs to be understood for laser deposited, welded and virgin H13. In this paper, H13 tool steel samples were made by laser deposition, welding and virgin H13 and then cut into pieces. Experiments were conducted to investigate the thermal diffusivity and conductivity. A laser flash method is used to test these samples. The future work and opportunities are also summarized.


Base Pressure Control Using Micro-Jets In Supersonic Flow Regimes, Vigneshvaran Sethuraman, Sher Afghan Khan 2018 Monash University Malaysia

Base Pressure Control Using Micro-Jets In Supersonic Flow Regimes, Vigneshvaran Sethuraman, Sher Afghan Khan

International Journal of Aviation, Aeronautics, and Aerospace

Base pressure plays a vital role in aerospace-related applications and its control is essential in reduction of drag and improving fuel consumption. Low pressure at the base of Rockets, Missiles, bombs and shells are a very common problem happening at transonic and supersonic speeds. In most of the cases there is a significant dip in pressure at the base region which will have implications on the design of aerospace vehicles. This paper presents an experimental investigation carried out for flow control at supersonic regimes. Experiments were conducted to measure the base pressure in the base region and wall pressure distribution ...


A Constellation Of Cubesats For The Measurement Of Thermospheric Density, Kimberly Wright, James Flynn, Susannah Miller 2018 Old Dominion University

A Constellation Of Cubesats For The Measurement Of Thermospheric Density, Kimberly Wright, James Flynn, Susannah Miller

Undergraduate Research Symposium

The ODU CubeSat is part of a multi-university collaborative project that aims to build a constellation of three small satellites that are shaped in the form of a cube with dimensions of 10 x 10 x 10 cm and will be deployed into Low Earth Orbit (LEO) to study phenomena that influence the varying thermosphere density. Variations in the density of the thermosphere fluctuate due to seasonal differences, changes in solar activity, solar radiation, and geomagnetic variations, along with temperature and altitude. These factors lead to uncertainties in current atmospheric drag models, which are a major source of error in ...


Subjectivity In Failure Mode Effects Analysis (Fmea) Severity Classification Within A Reliability Centered Maintenance (Rcm) Context, Marc Banghart, Kari Babski-Reeves, Linkan Bian, Lesley Strawderman 2018 ERAU

Subjectivity In Failure Mode Effects Analysis (Fmea) Severity Classification Within A Reliability Centered Maintenance (Rcm) Context, Marc Banghart, Kari Babski-Reeves, Linkan Bian, Lesley Strawderman

International Journal of Aviation, Aeronautics, and Aerospace

This research paper investigated subjectivity in the severity rating of failure modes within a risk analysis process. Although several risk analysis processes can be utilized, the study considered the application of Failure Modes Effects Analysis (FMEA) or Failure Modes Effects and Criticality Analysis (FMECA) due to its common use within the Aerospace Industry. The study investigated both differences in severity selection given varying amounts of experience as well as any association between severity selection and the provided input information. The main goal of the research was to investigate the impact of data quality on severity selection and to identify factors ...


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