Direct observation of the capillary mechanisms of liquid-liquid entrapment

The dissertation develops further insight into the behavior of liquid-liquid flow in porous media. This topic is of great importance with applications in chemical reaction engineering, enhanced oil recovery, and environmental remediation. This work focuses on the experimental observation of invading immiscible drops, the long term behavior of their interface, and their entrapment via capillary pressure and mobilization through vibratory stimulation. Using a simplified capillary physics mechanism several specific predictions can be made. So far these theories have generally agreed with CFD simulations, however a direct comparison to physical experiments is needed. Experiments were conducted using single pore glass capillaries. Straight capillaries were used to study the film thickness left by an invading drop, which is critical for determining realistic initial conditions for the interface theory. A range of constricted capillaries were used in verifying the ``breakup criterion\u27\u27 was influenced only by the geometric parameters of the capillary and not flow regimes. Additionally, the experiments and theory demonstrates qualitative agreement with respect to the evolution of the liquid-liquid interface. Finally, the theory of vibratory mobilization was verified by trapping single drops with a pressure below their mobilization threshold and observing the drop\u27s mobilization over several oscillations. The level of agreement between experiment, theory and CFD demonstrates the utility of the capillary physics mechanism in terms of reducing computational costs. The next goal is extending the theory to networks of pores so we can further our understanding of the oil mobilization and related processes, leading to useful technical applications

TRANSLATING THE INVISIBLE LANGUAGE OF LIGHT

This work discusses the relationship between art and science by the study of the fundamentals of light alongside an experimental process that emphasizes the transformation of matter, through which the main material of exploration is glass. Being exposed to scientific subjects throughout the master program facilitated a great interest and countless curiosities towards the nature of light from the point of view of an observer, but also as an experimenter and a maker. Through these inquiries, I recognized a relationship between the interaction of energy and matter, similar to the interaction of the artist with matter and space. Consequently I began a pursuit in which I immersed myself in a universe of light to later analyze its possible influence on my artwork and inevitably becoming part of the experiment myself. With this work, I seek to translate the above-mentioned interactions in order to create a visible artistic language. This is an attempt to approach science in a yet to be experienced way. Through glassmaking, I attempt to transform and materialize ideas about the nature of light in order to make a physically tangible vocabulary that will, hopefully, promote further understandings of light, life, the universe, and the world around me

Decoding STEM: The Impact of Science, Technology, Engineering, and Mathematics (STEM) Outreach Programming on English Language Learners

Science, technology, engineering, and mathematics (STEM) are often considered to be gatekeeping school subjects. The language used in STEM education and traditional pedagogies which place emphasis on textbook learning can be challenging for students, especially those who are learning English at the same time. This case study examines a cohort of English Language Learners (ELLs) selected from a larger longitudinal STEM study that aimed to investigate how school partnerships with STEM outreach programs model alternative pedagogical strategies through hands-on inquiry models to effectively engage ELLs, as well as support STEM learning and second language acquisition (SLA) concurrently. Findings indicate that STEM outreach programs can support attitude, interest, and self-efficacy in both STEM and SLA due to specific distinguishing features. In the context of this study, these features include: (a) access to hands-on learning; (b) agency by design; and (c) access to peer learning networks. Jointly, self-efficacy, attitude, and interest come together to support ELLs in STEM over time

Silent Light, Luminous Noise: Photophonics, Machines and the Senses

This research takes the basic physical premise that sound can be synthesized using light, explores how this has historically been, and still is achieved, and how it can still be a fertile area for creative, theoretical and critical exploration in sound and the arts. Through the author's own artistic practice, different techniques of generating sound using the sonification of light are explored, and these techniques are then contextualised by their historical and theoretical setting in the time-based arts. Specifically, this text draws together diverse strands of scholarship on experimental sound and film practices, cultural histories, the senses, media theory and engineering to address effects and outcomes specific to photophonic sound and its relation to the moving image, and the sculptural and media works devised to produce it. The sonifier, or device engendering the transformations discussed is specifically addressed in its many forms, and a model proposed, whereby these devices and systems are an integral, readably inscribed component - both materially and culturally - in both the works they produce, and via our reflexive understanding of the processes involved, of the images or light signals used to produce them. Other practitioners' works are critically engaged to demonstrate how a sense of touch, or the haptic, can be thought of as an emergent property of moving image works which readably and structurally make use of photophonic sound (including the author's), and sound's essential role in this is examined. In developing, through an integration of theory and practice, a new approach in this under-researched field of sound studies, the author hopes to show how photophonic sound can act as both a metaphorical and material interface between experimental sound and image, and hopefully point the way towards a more comprehensive study of both

Flow Field Dynamics in a High-g Ultra-Compact Combustor

The Ultra Compact Combustor (UCC) presents a novel solution to the advancement of aircraft gas turbine engine performance. A high-g UCC design operates by diverting a portion of the axial compressor flow into a circumferential combustion cavity positioned about the engine outer diameter. The circumferential cavity (CC) provides the necessary residence length and time for combustion within reduced axial lengths; furthermore, high rates of centrifugal acceleration termed high-g loading are imposed upon the swirling cavity flow. These high-g conditions are hypothesized to increase flame speed, reduce flame length, and improve lean blow-out performance. Work at AFIT was sponsored by the Air Force Office of Scientific Research to study high-g combustion. This research capitalized on the availability of advanced flow diagnostic data coupled with a computational fluid dynamics (CFD) model to provide detailed insight into the high-g flow field and combustion dynamics. Results indicated that combustion could be sustained and controlled in a manner suitable for integration into modern gas turbine engine architecture

On the Applicability of Genetic Algorithms to Fast Solar Spectropolarimetric Inversions for Vector Magnetography

The measurement of vector magnetic fields on the sun is one of the most important diagnostic tools for characterizing solar activity. The ubiquitous solar wind is guided into interplanetary space by open magnetic field lines in the upper solar atmosphere. Highly-energetic solar flares and Coronal Mass Ejections (CMEs) are triggered in lower layers of the solar atmosphere by the driving forces at the visible ``surface\u27\u27 of the sun, the photosphere. The driving forces there tangle and interweave the vector magnetic fields, ultimately leading to an unstable field topology with large excess magnetic energy, and this excess energy is suddenly and violently released by magnetic reconnection, emitting intense broadband radiation that spans the electromagnetic spectrum, accelerating billions of metric tons of plasma away from the sun, and finally relaxing the magnetic field to lower-energy states. These eruptive flaring events can have severe impacts on the near-Earth environment and the human technology that inhabits it. This dissertation presents a novel inversion method for inferring the properties of the vector magnetic field from telescopic measurements of the polarization states (Stokes vector) of the light received from the sun, in an effort to develop a method that is fast, accurate, and reliable. One of the long-term goals of this work is to develop such a method that is capable of rapidly-producing characterizations of the magnetic field from time-sequential data, such that near real-time projections of the complexity and flare-productivity of solar active regions can be made. This will be a boon to the field of solar flare forecasting, and should help mitigate the harmful effects of space weather on mankind\u27s space-based endeavors. To this end, I have developed an inversion method based on genetic algorithms (GA) that have the potential for achieving such high-speed analysis

Manned Mars System Study (MMSS): Mars transportation and facility infrastructure study. Volume 2: Technical report

The Manned Mars System Study (MMSS) was conducted for the Marshall Space Flight Center (MSFC) over the 35 month period between May 15, 1987 and April 30, 1990. During the course of the study, the NASA Office of Exploration (OEXP; Code Z) was created and MSFC was subsequently designated the Transportation Integration Agent (TIA) for support of the OEXP Mission Analysis and Systems Engineering (MASE) team. As a result of this action, modifications to the contract redirected the efforts to be consistent with NASA's overall objectives, including lunar transportation system design. A large number of written submittals were required in order to provide TIA support to MASE. A list summarizing the documents which have been prepared and delivered by Martin Marietta under this contract during the course of this work is presented. In nearly all cases, full sets of view-graphs were also provided to the MSFC COTR, and in several cases magnetic media were provided as well. To incorporate all of these materials (more than 2,000 pages) into the present report would obviously produce an extremely unwieldy and confusing document. Therefore, a summary of key findings are presented in this final report, supplemented by other material produced under this contract but not already available in the widespread literature