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Aerospace Engineering Commons

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2017

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Articles 61 - 90 of 468

Full-Text Articles in Aerospace Engineering

Transient Analysis Of Fracture Initiation In A Coupled Thermoelastic Solid, Louis Milton Brock Nov 2017

Transient Analysis Of Fracture Initiation In A Coupled Thermoelastic Solid, Louis Milton Brock

Mechanical Engineering Faculty Publications

An isotropic, thermoelastic solid is initially at rest at uniform (absolute) temperature, and contains a semi-infinite, plane crack. Application of in-plane and normal point forces to each face of the crack causes transient 3D growth. The related problem of discontinuities in temperature and displacement that exist on regions that exhibit dynamic similarity is first considered. Asymptotic expressions, whose inverses are valid near the crack edges for short times, are obtained in integral transform space. These lead to equations of the Wiener–Hopf type for the fracture problem. Analytical solutions are obtained and, upon inversion, subjected to a dynamic energy release rate …


Experimental Measurement Of Residual Stress And Distortion In Additively Manufactured Stainless Steel Components With Various Dimensions, M. Ghasri-Khouzani, H. Peng, R. Rogge, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar Nov 2017

Experimental Measurement Of Residual Stress And Distortion In Additively Manufactured Stainless Steel Components With Various Dimensions, M. Ghasri-Khouzani, H. Peng, R. Rogge, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Disk-shaped 316L stainless steel parts with various diameters and heights were additively manufactured using a direct metal laser sintering (DMLS) technique. Neutron diffraction was used to profile the residual stresses in the samples before and after removal of the build plate and support structures. Moreover, distortion level of the parts before and after the removal was quantified using a coordinate measuring machine (CMM). Large tensile in-plane stresses (up to ≈ 400 MPa) were measured near the as-built disk top surfaces, where the stress magnitude decreased from the disk center to the edges. The stress gradient was steeper for the disks …


Progress Towards An Opposed Piston Two Stroke Gasoline Aviation Engine, Donald R. Morris Nov 2017

Progress Towards An Opposed Piston Two Stroke Gasoline Aviation Engine, Donald R. Morris

ASA Multidisciplinary Research Symposium

Opposed Piston Engine Technology is not new, but its application to small two-stroke gasoline engines is unexplored. This presentation explores the potential advantages of such an engine as well as progress towards a workable design.


Uas (Unmanned Aircraft Systems): Challenges And Opportunities, Andy Wang Nov 2017

Uas (Unmanned Aircraft Systems): Challenges And Opportunities, Andy Wang

ASA Multidisciplinary Research Symposium

Experts in UAS (drones) applications and R&D will discuss new business applications, business opportunities, and latest R&D results.


Fdm Machine Learning: An Investigation Into The Utility Of Neural Networks As A Predictive Analytic Tool For Go Around Decision Making, John Bro Nov 2017

Fdm Machine Learning: An Investigation Into The Utility Of Neural Networks As A Predictive Analytic Tool For Go Around Decision Making, John Bro

ASA Multidisciplinary Research Symposium

FDM MACHINE LEARNING: An investigation into the utility of neural networks as a predictive analytic tool for go around decision making.


A Study On The E-Navigation Modus Operandi, Nurma Karima Sari Nov 2017

A Study On The E-Navigation Modus Operandi, Nurma Karima Sari

World Maritime University Dissertations

No abstract provided.


Alternative Mission Concepts For The Exploration Of Outer Planets Using Small Satellite Swarms, Andrew Gene Blocher Nov 2017

Alternative Mission Concepts For The Exploration Of Outer Planets Using Small Satellite Swarms, Andrew Gene Blocher

Master's Theses

Interplanetary space exploration has thus far consisted of single, expensive spacecraft missions. Mission costs are particularly high on missions to the outer planets and while invaluable, finite budgets limit our ability to perform extensive and frequent investigations of the planets. Planetary systems such as Jupiter and Saturn provide extremely complex exploration environments with numerous targets of interest. Exploring these targets in addition to the main planet requires multiple fly-bys and long mission timelines. In LEO, CubeSats have changed the exploration paradigm, offering a fast and low cost alternative to traditional space vehicles. This new mission development philosophy has the potential …


Development And Characterization Of Piezoresistive Nanocomposites For Sensing Applications, Muhammad Anees Nov 2017

Development And Characterization Of Piezoresistive Nanocomposites For Sensing Applications, Muhammad Anees

Doctoral Dissertations and Master's Theses

Carbonnanotube basedhybrid nanocomposites are known to exhibit remarkable electrical and mechanical properties with many potentials in strain and damage sensing applications. In this work, we fabricate hybrid nanocomposites with carbon nanotube (CNT) sheet and graphene nanoplatelets (GNP) as fillers with epoxy matrix. An improvement in both electrical conductivity and piezoresistivity is observed with the combination of CNTs and GNPs, indicating the formation of efficient hybrid conductive networks for strain and electrical transfer in the material. Different matrix materials have been compared to investigate the effect of matrix and to choose the one that yields increased strains, flexibility, and electromechanical response. …


Analytical And Numerical Approaches On The Stiffness Of Magnetorheological Fluid Filled Spring, Stanislav Sikulskyi Nov 2017

Analytical And Numerical Approaches On The Stiffness Of Magnetorheological Fluid Filled Spring, Stanislav Sikulskyi

Doctoral Dissertations and Master's Theses

A solid mechanical spring generally exhibits uniform stiffness. This thesis studies a mechanical spring filled with magnetorheological (MR) fluid to achieve controllable stiffness. The hollow spring filled with MR fluid is subjected to a controlled magnetic field in order to change the viscosity of the MR fluid and thereby to change the overall stiffness of the spring. MR fluid is considered as a Bingham viscoplastic linear material in the mathematical model. The goal of this research is to study the feasibility of such spring system by analytically and numerically computing the effects of MR fluid on the overall spring stiffness. …


Verification, Validation And Application Of Shear Stress Transport Transitional Model To A R/C Aircraft, Jon Willems Nov 2017

Verification, Validation And Application Of Shear Stress Transport Transitional Model To A R/C Aircraft, Jon Willems

Doctoral Dissertations and Master's Theses

Accurate numerical prediction of transition onset as well as transition extent is crucial when evaluating the performance of many remotely controlled and autonomous aircraft. The four-equation Menter-Langtry Transitional viscous model in ANSYS Fluent is applied to a number of 2D and 3D airfoils and wings operating within the transitional flow regime, to permit comparison to relevant experimental and numerical results for transition onset, extent, and overall aerodynamic performance. The sensitivity to grid topology and fineness is also examined. With sufficient confidence in the numerical approach, the performance of a well-known high performance R/C glider is examined and compared to results …


University Of Minnesota Smallsat And High Altitude Ballooning Development And Collaboration, Luke Zumwalt, Ricardo Saborio, Athanasios Pantazides, Aaron Nightingale, Demoz Gebre Egziabher, Lindsay Glesener Oct 2017

University Of Minnesota Smallsat And High Altitude Ballooning Development And Collaboration, Luke Zumwalt, Ricardo Saborio, Athanasios Pantazides, Aaron Nightingale, Demoz Gebre Egziabher, Lindsay Glesener

2017 Academic High Altitude Conference

The Experiment for X-ray Characterization and Timing (EXACT) mission is a 3U CubeSat technology-development project being built by the SmallSat team at the University of MN – Twin Cities which is a joint research effort of the Aerospace Engineering and Mechanics (AEM) Department and the School of Physics and Astronomy (SPA). The main objective of this spacecraft is to carry a payload including a detector designed to measure energy and time of arrival time of individual hard x-ray photons emitted from the Sun and from other astrophysical sources. During the development process for EXACT, flights provided by the High-Altitude Student …


Solar Eclipse Induced Atmospheric Turbulence Effects On High Altitude Balloons, Fnu Anamika, Denise Buckner, Peter Henson, Jennifer Fowler, Nanette Valentour Oct 2017

Solar Eclipse Induced Atmospheric Turbulence Effects On High Altitude Balloons, Fnu Anamika, Denise Buckner, Peter Henson, Jennifer Fowler, Nanette Valentour

2017 Academic High Altitude Conference

The North Dakota Atmospheric Education Student Initiated Research (ND-AESIR) team launched a balloon during the total solar eclipse in Rexburg, Idaho. After the umbra’s passage, the balloon experienced unexpectedly high levels of atmospheric turbulence. Video footage taken from the payload displays the conditions, and analysis of flight path data models created from the iridium GPS confirm that unusually violent turbulence occurred. These forces caused the key rings holding the bottom of the parachute to the payload train to rip open; the balloon and parachute flew away and the payloads free fell to the surface from an altitude of 68,301 feet. …


How Iridium Satellite Tracker Model 9602-Lp Asset Affects Span Of Control In High Altitidue Balloning, Steven Hamby Oct 2017

How Iridium Satellite Tracker Model 9602-Lp Asset Affects Span Of Control In High Altitidue Balloning, Steven Hamby

2017 Academic High Altitude Conference

The Irdium Satelitte Network has greatly increased safety in the ballooning field by enabling a greater span of control in flight awarness and termination. This enhanced awareness stems from accurate high interval GPS coordinates that can be integrated into ground station tracking software. The Iridium Network creates the ability to send activation commands remotely with high reliabilty using emails. Additionally this feature has the ability to use local rf transmiters and recievers to increase the flexibilty of cutdown designs. The Iridium Modems provides significant coverage regardless of altitude and loss of ground communication. It is marketed at econmical price point …


Ground Station Tracking System, Garret Hilton, Carter Mciver, Steven Hamby, Trevor Gahl, Casey Coffman, David Schwehr Oct 2017

Ground Station Tracking System, Garret Hilton, Carter Mciver, Steven Hamby, Trevor Gahl, Casey Coffman, David Schwehr

2017 Academic High Altitude Conference

One of the Eclipse Ballooning Project’s main goals was to stream live video of the eclipse to the internet. To accomplish this task a tracking antenna was built to follow the balloon payload. As an added challenge, the task had to be completed on a budget. The “ground station” is the center for communication between the payload and user. This system utilizes GPS position reports from the payload via the iridium network to determine the balloons position. The computer algorithm takes in additional GPS and IMU data from the ground station to determine a relative heading to orientate the antenna …


High Altitude Balloon Flight Predictions, Sara Stafford Oct 2017

High Altitude Balloon Flight Predictions, Sara Stafford

2017 Academic High Altitude Conference

The ability to make accurate predictions of a high altitude balloon’s flight trajectory is critical for safety, protection of sensitive payloads, and ease of payload recovery. Several free software programs and websites are available which make predictions straightforward and yield acceptable results. Additional resources are presented which help evaluate the stability of the projected flight track. The various methods of prediction will be described and results compared with actual flight data.


Placing A High-Altitude Balloon In The Path Of Totality, Nicholas Jordan, Christopher Helmerich Oct 2017

Placing A High-Altitude Balloon In The Path Of Totality, Nicholas Jordan, Christopher Helmerich

2017 Academic High Altitude Conference

The UAH Space Hardware Club had conducted 70 flights prior to the Eclipse. In this time, we have gained valuable skills and experience which we have put into practice and passed on through the years. We put these skills into practice for the Eclipse. Our first challenge was finding where to launch. We started out by looking for suitable locations inside totality. We also examined a map of totality at 80,000 ft. We then ran predictions based on past weather during that time of year. By compiling multiple past predictions, we eliminated possible launch sites. We had multiple payloads, some …


Autonomous Solid-State Radiation Detector For Safety Of Aerospace Systems, Levi Davies, Biswajit Ray Oct 2017

Autonomous Solid-State Radiation Detector For Safety Of Aerospace Systems, Levi Davies, Biswajit Ray

Von Braun Symposium Student Posters

No abstract provided.


Experimentation Of Warm Gas Generator Emerging Technologies, Amit Patel Oct 2017

Experimentation Of Warm Gas Generator Emerging Technologies, Amit Patel

Von Braun Symposium Student Posters

No abstract provided.


Upgrade Of Prc Spray Facility For Evaluation Of Liquid Injector Technology, Ronak Aj Pereira, Julian Schröder Oct 2017

Upgrade Of Prc Spray Facility For Evaluation Of Liquid Injector Technology, Ronak Aj Pereira, Julian Schröder

Von Braun Symposium Student Posters

No abstract provided.


Development Of A Multistage High-Power Rocket, James Biaglow, Mckynzie Perry, Aaron Hunt Oct 2017

Development Of A Multistage High-Power Rocket, James Biaglow, Mckynzie Perry, Aaron Hunt

Von Braun Symposium Student Posters

No abstract provided.


Uah Propulsion Research Center Rocket Test Capability Upgrade, Daniel A. Jones Oct 2017

Uah Propulsion Research Center Rocket Test Capability Upgrade, Daniel A. Jones

Von Braun Symposium Student Posters

No abstract provided.


Marshall Enriched Storable Oxidizer, R Dalton Hicks Oct 2017

Marshall Enriched Storable Oxidizer, R Dalton Hicks

Von Braun Symposium Student Posters

No abstract provided.


How Spaceflight Affects The Detachment Of Zinc Whiskers, Kayla Capitan Oct 2017

How Spaceflight Affects The Detachment Of Zinc Whiskers, Kayla Capitan

Von Braun Symposium Student Posters

No abstract provided.


Cylindrical Hall Effect Thruster With 3d Printed Components For Small Satellite Propulsion, Ryota Nakano, Gabriel Xu Oct 2017

Cylindrical Hall Effect Thruster With 3d Printed Components For Small Satellite Propulsion, Ryota Nakano, Gabriel Xu

Von Braun Symposium Student Posters

No abstract provided.


Design And Construction Of A Bi-Propellant Liquid Rocket, Kaitlin Russell, Mckynzie Perry, Erik Korzon, Rilee Kaliher, Grant Elliott, Claire Daly Oct 2017

Design And Construction Of A Bi-Propellant Liquid Rocket, Kaitlin Russell, Mckynzie Perry, Erik Korzon, Rilee Kaliher, Grant Elliott, Claire Daly

Von Braun Symposium Student Posters

No abstract provided.


Miniaturizing Ion Thruster Using Split Ring Resonator (Srr), Toyofumi Yamauchi, Gabriel Xu Oct 2017

Miniaturizing Ion Thruster Using Split Ring Resonator (Srr), Toyofumi Yamauchi, Gabriel Xu

Von Braun Symposium Student Posters

No abstract provided.


Overview Of The Saber Mission And Launch Vehicle Design, Benjamin Thompson, Jared Fuchs, Oakley Copeland, Aaron Hunt, Matthew Haskell, William Hankins, Logan Anderson Oct 2017

Overview Of The Saber Mission And Launch Vehicle Design, Benjamin Thompson, Jared Fuchs, Oakley Copeland, Aaron Hunt, Matthew Haskell, William Hankins, Logan Anderson

Von Braun Symposium Student Posters

No abstract provided.


Prediction-Based Adaptive Robust Control For A Class Of Uncertain Time-Delay Systems, Jayaprakash Suraj Nandiganahalli, Cheolhyeon Kwon, Inseok Hwang Oct 2017

Prediction-Based Adaptive Robust Control For A Class Of Uncertain Time-Delay Systems, Jayaprakash Suraj Nandiganahalli, Cheolhyeon Kwon, Inseok Hwang

School of Aeronautics and Astronautics Faculty Publications

This paper presents an integrated control design approach for a class of dynamical systems that satisfy a certain matching condition subject to known input time-delay, unknown parameters, and time-varying disturbances, simultaneously. A novel nonlinear predictor adaptive robust control (PARC) is proposed to track a desired state trajectory. The controller uses predictor-based model compensation to attenuate the effect of input time-delay, gradient type projection with prediction-based learning mechanisms to reduce the parameter uncertainties, and prediction-based nonlinear robust feedback to attenuate the effect of model approximation errors and disturbances, simultaneously. The controller guarantees a prescribed transient performance (with global exponential convergence) and …


Develop Pucp Microlab For Thinsat, Robert J. Twiggs Oct 2017

Develop Pucp Microlab For Thinsat, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Develop PUCP microlab for ThinSat" from October 17, 2017.


Blended Wing Body Propulsion System Design, Parth Kumar, Adeel Khalid Oct 2017

Blended Wing Body Propulsion System Design, Parth Kumar, Adeel Khalid

International Journal of Aviation, Aeronautics, and Aerospace

This research paper focuses on the optimization of the propulsion system of a blended wing body design. Two different aspects of the design, the engine placement and count, and the engine itself, are investigated. The preliminary wing of the BWB is created through aerodynamic analysis, and is kept as a constant over the different propulsion system configurations. The engine parameters are first investigated. Equations are derived to express takeoff distance and climb rate as a function of engine sea level thrust, cruise thrust, and the number of engines. Nearly 150 different engine models, in BWB configurations of 2, 3, 4, …