Study of the true performance limits of the Astrometric Multiplexing Area Scanner (AMAS)

The Astrometric Multiplexing Area Scanner (AMAS) is an instrument designed to perform photoelectric long focus astrometry of small fields. Modulation of a telescope focal plane with a rotating Ronchi ruling produces a frequency modulated signal from which relative positions and magnitudes can be extracted. Evaluation instrumental precision, accuracy and resolution characteristics with respect to a variety of instrumental and cosmical parameters indicates 1.5 micron precision and accuracy for single stars under specific conditions. This value decreases for increased number of field stars, particularly for fainter stars

In the blood

Access to thesis permanently restricted to Ball State community only.This creative project is a short story about a small town in Wisconsin that is suffering from a modern-day diphtheria outbreak. The story is told through the eyes of a woman who is watching the events unfold through the only means she can, via social media. The story is written in a fragmented style, incorporating newspaper articles and social media posts intermixed with the narrator’s reflections. This story was inspired by the non-fiction book Wisconsin Death Trip by Michael Lesy, which is a collection of photographs and news articles tracing diphtheria outbreaks, rampant arson, and the strange behavior of the residents of the town of Black River Fall, Wisconsin in the late 19th century. My goal in writing this story was to lean into some of the thematic and stylistic obsessions I have as a writer such as writing about small Wisconsin towns and unsettling occurrences via fragmented narrative structures.Department of EnglishThesis (M.A.

Pensacola During the Second Spanish Period

On the first day of January, 1777, an event in New Orleans was to have important consequences for the history of Pensacola: Bernardo de Galvez formally assumed the governorship of Louisiana. Galvez was typical of the colonial officials who were appointed during that Indian Summer of Spanish Imperial history, the reign of Charles III. A career officer in the royal armies, he had already distinguished himself in several theaters: first in Portugal, then in Mexico against the Indians on the northern frontier where, under his famous uncle Jose de Galvez, he displayed those traits of energy, initiative, and leadership which characterized his subsequent career. During the next few years he served in the French army for training purposes and in 1776 was ordered to New Orleans as commander of the garrison and subsequently promoted to the governorship of the colony while still less than thirty years of age

Dynamic stall experiments on the NACA 0012 airfoil

The flow over a NACA 0012 airfoil undergoing large oscillations in pitch was experimentally studied at a Reynolds number of and over a range of frequencies and amplitudes. Hot-wire probes and surface-pressure transducers were used to clarify the role of the laminar separation bubble, to delineate the growth and shedding of the stall vortex, and to quantify the resultant aerodynamic loads. In addition to the pressure distributions and normal force and pitching moment data that have often been obtained in previous investigations, estimates of the unsteady drag force during dynamic stall have been derived from the surface pressure measurements. Special characteristics of the pressure response, which are symptomatic of the occurrence and relative severity of moment stall, have also been examined

Analysis of the development of dynamic stall based on oscillating airfoil experiments

The effects of dynamic stall on airfoils oscillating in pitch were investigated by experimentally determining the viscous and inviscid characteristics of the airflow on the NACA 0012 airfoil and on several leading-edge modifications. The test parameters included a wide range of frequencies, Reynolds numbers, and amplitudes-of-oscillation. Three distinct types of separation development were observed within the boundary layer, each leading to classical dynamic stall. The NACA 0012 airfoil is shown to stall by the mechanism of abrupt turbulent leading-edge separation. A detailed step-by-step analysis of the events leading to dynamic stall, and of the results of the stall process, is presented for each of these three types of stall. Techniques for flow analysis in the dynamic stall environment are discussed. A method is presented that reduces most of the oscillating airfoil normal force and pitching-moment data to a single curve, independent of frequency or Reynolds number

An experimental study of dynamic stall on advanced airfoil section. Volume 2: Pressure and force data

Experimentally derived force and moment data are presented for eight airfoil sections that were tested at fixed and varying incidence in a subsonic two dimensional stream. Airfoil incidence was varied through sinusoidal oscillations in pitch over a wide range of amplitude and frequency. The surface pressure distribution, as well as the lift, drag, and pitching moment derived therefrom, are displayed in a uniform fashion to delineate the static and dynamic characteristics of each airfoil both in and out of stall