Aerospace Engineering Commons^™

Development Of Boron-Containing Polyimide Materials And Poly(Arylene Ether)S For Radiation Shielding, Brittani May Collins

Dissertations, Theses, and Masters Projects

No abstract provided.

High-Performance Nanocomposites Designed For Radiation Shielding In Space And An Application Of Gis For Analyzing Nanopowder Dispersion In Polymer Matrixes, Joseph Simcha Auslander

Dissertations, Theses, and Masters Projects

No abstract provided.

Polymeric Radiation Shielding For Applications In Space: Polyimide Synthesis And Modeling Of Multi-Layered Polymeric Shields, Clinton Cleveland Schiavone

Dissertations, Theses, and Masters Projects

No abstract provided.

Production Of Cyclohexylene-Containing Diamines In Pursuit Of Novel Radiation Shielding Materials, Norah G. Bate

Dissertations, Theses, and Masters Projects

No abstract provided.

Advancements In Dual-Pump Broadband Cars For Supersonic Combustion Measurements, Sarah Augusta. Tedder

Dissertations, Theses, and Masters Projects

Space- and time-resolved measurements of temperature and species mole fractions of nitrogen, oxygen, and hydrogen were obtained with a dual-pump coherent anti-Stokes Raman spectroscopy (CARS) system in hydrogen-fueled supersonic combustion free jet flows. These measurements were taken to provide time-resolved fluid properties of turbulent supersonic combustion for use in the creation and verification of computational fluid dynamic (CFD) models. CFD models of turbulent supersonic combustion flow currently facilitate the design of air- breathing supersonic combustion ramjet (scramjet) engines. Measurements were made in supersonic axi-symmetric free jets of two scales. First, the measurement system was tested in a laboratory environment using …

Multifunctional Polymer Synthesis And Incorporation Of Gadolinium Compounds And Modified Tungsten Nanoparticles For Improvement Of Radiation Shielding For Use In Outer Space, Emily Grace Harbert

Dissertations, Theses, and Masters Projects

No abstract provided.

Parallel Unstructured Grid Generation For Complex Real-World Aerodynamic Simulations, George Zagaris

Dissertations, Theses, and Masters Projects

No abstract provided.

Fluorescence Imaging Study Of Free And Impinging Supersonic Jets: Jet Structure And Turbulent Transition, Jennifer Ann Inman

Dissertations, Theses, and Masters Projects

A series of experiments into the behavior of underexpanded jet flows has been conducted at NASA Langley Research Center. This work was conducted in support of the Return to Flight effort following the loss of the Columbia. The tests involved simulating flow through a hypothetical breach in the leading edge of the Space Shuttle Orbiter along its reentry trajectory, with the goal of generating a data set with which other researchers can test and validate computational modeling tools. Two nozzles supplied with high-pressure gas were used to generate axisymmetric underexpanded jets exhausting into a low-pressure chamber. These nozzles had exit …

A Semi-Empirical Cellular Automata Model For Wildfire Monitoring From A Geosynchronous Space Platform, Brian D. Killough

Dissertations, Theses, and Masters Projects

The environmental and human impacts of wildfires have grown considerably in recent years due to an increase in their frequency and coverage. Effective wildfire management and suppression requires real-time data to locate fire fronts, model their propagation and assess the impact of biomass burning. Existing empirical wildfire models are based on fuel properties and meteorological data with inadequate spatial or temporal sampling. A geosynchronous space platform with the proposed set of high resolution infrared detectors provides a unique capability to monitor fires at improved spatial and temporal resolutions. The proposed system is feasible with state-of-the-art hardware and software for high …

Tomography Applied To Lamb Wave Contact Scanning Nondestructive Evaluation, James Christopher P. Mckeon

Dissertations, Theses, and Masters Projects

The aging world-wide aviation fleet requires methods for accurately predicting the presence of structural flaws that compromise airworthiness in aircraft structures. Nondestructive Evaluation (NDE) provides the means to assess these structures quickly, quantitatively, and noninvasively. Ultrasonic guided waves, Lamb waves, are useful for evaluating the plate and shell structures common in aerospace applications. The amplitude and time-of-flight of Lamb waves depend on the material properties and thickness of a medium, and so they can be used to detect any areas of differing thickness or material properties which indicate flaws. By scanning sending and receiving transducers over an aircraft, large sections …

Development Of Radiation Shielding Materials For Space Applications, Stephen C. Ko

Dissertations, Theses, and Masters Projects

No abstract provided.

Discrete-Time Linear And Nonlinear Aerodynamic Impulse Responses For Efficient Cfd Analyses, Walter A. Silva

Dissertations, Theses, and Masters Projects

This dissertation discusses the mathematical existence and the numerical identification of linear and nonlinear aerodynamic impulse response functions. Differences between continuous-time and discrete-time system theories, which permit the identification and efficient use of these functions, will be detailed. Important input/output definitions and the concept of linear and nonlinear systems with memory will also be discussed. It will be shown that indicial (step or steady) responses (such as Wagner's function), forced harmonic responses (such as Theodorsen's function or those from doublet lattice theory), and responses to random inputs (such as gusts) can all be obtained from an aerodynamic impulse response function. …

Campus And Consortium In An Era Of Large-Scale Research: An Historical Study Of The Virginia Associated Research Center, 1962-1967, Elizabeth Buchanan Ward

Dissertations, Theses, and Masters Projects

A large agency of the Federal Government, three public institutions of higher learning, and two agents of State Government in the Commonwealth of Virginia launched a federally funded research and education consortium in 1962. The Virginia Associated Research Center (VARC) promised great success. The University of Virginia, Virginia Polytechnic Institute, and The College of William and Mary joined forces to provide the National Aeronautics and Space Administration's Langley Research Center with a scientific research base and a graduate education program. The Commonwealth initially provided enthusiastic support from the Governor's office and from the State Council for Higher Education.;The three colleges …

The Aerodynamics Of Flapping Birdflight, Carol Coughlin, Virginia Institute Of Marine Science

Reports

No abstract provided.

A Mathematical Analysis Of The Dynamic Soaring Flight Of The Albatross With Ecological Interpretations, Carol Coughlin

Reports

The capability of flight plays a central role in the lives of most birds. Indeed, the existing morphological and ecological characteristics of many species are almost entirely dictated by the aerodynamic requirements of the highly developed flight modes they have acquired through evolutional specialization. In the case of such species, a clear understanding of the aerodynamic mechanisms underlying the particular flight modes can often provide a lucid insight into the basic physical relationships which govern a bird's characteristic activities and behavior.

This aerodynamic approach to the study of avian ecology is particularly useful in the case of soaring birds, where …

On The Problem Of Radio Signal Attenuation During Hypervelocity Reentry, David Joseph Romeo

Dissertations, Theses, and Masters Projects

No abstract provided.

Diurnal And Seasonal Variations Of Satellite Scintillation, John David Martin

Dissertations, Theses, and Masters Projects

No abstract provided.

Wind-Tunnel Measurements Of The Aerodynamic Damping And Oscillatory Stability In Pitch Of A Sphere At Mach Numbers From 0.20 To 4.63, Robert Ashworth Kilgore

Dissertations, Theses, and Masters Projects

No abstract provided.

A Theory Of Space Probe Entry Near The Low-Meteoric Velocity Limit, Frederick Cyril Grant

Dissertations, Theses, and Masters Projects

No abstract provided.