Theses and Dissertations at Montana State University (MSU)
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Item High-fidelity simulations of a rotary bell atomizer with electrohydrodynamic effects(Montana State University - Bozeman, College of Engineering, 2023) Pydakula Narayanan, Venkata Krisshna; Chairperson, Graduate Committee: Mark OwkesAtomizing flows involve the breakup of a liquid into a spray of droplets. These flows play a vital role in various industrial applications such as spray painting and fuel injection. In particular, these processes can have severe impacts especially in automotive paint shops - which can account for up to 50% of the total costs and 80% of the environmental concerns in an automobile manufacturing facility. A device commonly used for painting vehicles is called an electrostatic rotary bell atomizer (ERBA). ERBAs rotate at high speeds while electrically charging the liquid and operating in a background electric field to direct atomized charged droplets towards the target surface. The atomization process directly influences the transfer efficiency (TE) and surface finish quality. Optimal spray parameters used in industry are often obtained from expensive trial-and-error methods. To overcome these limitations, a computational tool has been developed to simulate three-dimensional near-bell ERBA atomization using a high-fidelity volume-of-fluid transport scheme. Additionally, the solver is equipped with physics modules including centrifugal, Coriolis, electrohydrodynamic (EHD), and shear-thinning viscous force models. The primary objective of this research is to investigate the influence of EHD parameters on near-bell atomization of paint and subsequently improve TE in ERBAs in a cost-effective manner. Using the tools developed, numerical simulations are performed to understand the physics of electrically assisted atomization. The influence of various operating parameters, such as liquid flow rate, bell rotation rate, liquid charge density, and bell electric potential, on atomization is examined. Results from a comparative study indicate that the electric field accelerates breakup processes and enhances secondary atomization. The droplet velocity, local Weber number and charge density statistics are also analyzed to understand the complex physics in electrically assisted breakup. Additionally, the effect of shear-thinning behavior of the liquid on atomization is also explored. High-fidelity simulations allow for the extraction of breakup statistics which are otherwise challenging to obtain experimentally. These findings have the potential to drive improvements in the design and operation of ERBAs, leading to enhanced TE and surface finish quality while reducing costs and environmental concerns in automotive paint shops.Item Computationally modeling the aeroelastic physics of flapping-wing flight(Montana State University - Bozeman, College of Engineering, 2023) Schwab, Ryan Keith; Chairperson, Graduate Committee: Mark Jankauski; This is a manuscript style paper that includes co-authored chapters.Flying insects use flapping wings to achieve flight at minuscule sizes. These flapping wings deform elastically under both inertial and aerodynamic loading. While conventional aircraft are often designed to reduce flexibility in their wings, insects harness the benefits of wing flexibility through elastic potential energy storage and enhancement of flapping wing- specific aerodynamic phenomena. Aircraft at insect size scales could have an inexhaustible number of uses ranging from monitoring of congested piping networks in oil refineries, to extraterrestrial land surveyance in thin atmospheres. If these micro air vehicles are to be realized, however, they will need to harness the aerodynamic benefits of flapping wings in order to overcome unfavorable ratios of lift to drag forces and inefficiencies of DC motors at such small sizes. Study of flapping wing aeroelastics is complicated due to the large-amplitude rotations of the wings, unsteady dynamics of the fluid regime, and small size and weight scales of the wings. While some experimental work focuses on techniques like measuring kinematics through motion tracking with high-speed videography, and partial flow field measurements through particle image velocimetry, it is difficult to conduct experiments that paint a full picture of the fluid-structure interaction of these wings. Instead, this research focuses on high-fidelity computational modeling through bilaterally coupled computational fluid dynamics and finite element analysis software to understand the fluid-structure interaction of flapping wings. In this work, a reduced order modeling technique capable of calculating the bulk aeroelastic physics of flapping wings at computational efficiencies suitable for parameter optimization studies was also validated. Finally, the influence of tapered wing thickness on aeroelastics and energetic efficiency was studied. While wing tapering reduced mean thrust, it had a greater reduction on the energetic requirement to produce flapping kinematics and was therefore more energetically efficient.Item The impact of technology on engagement and content mastery in high school biology(Montana State University - Bozeman, College of Letters & Science, 2022) Livesay, Jennifer Marie; Chairperson, Graduate Committee: C. John GravesThe use of technology-mediated versus traditional paper-based delivery methods as a means of increasing student mastery and engagement was studied in the areas of notetaking and simulations. Data collection instruments included pre- and post-content tests with confidence response measures as well as both Likert-item and open-ended response surveys. Data was analyzed using both quantitative and qualitative methods. The results indicate that technology leads to increased levels of engagement and mastery when utilized as a way to model scientific processes, but a decrease of mastery and engagement when used as the medium for notetaking.Item A 3D anatomy app as a learning tool(Montana State University - Bozeman, College of Letters & Science, 2022) MacKenzie, Michael John; Chairperson, Graduate Committee: C. John GravesComplete Anatomy is a digital 3D anatomy platform that allows users to manipulate virtual human models. The purpose of this study was to determine whether the students perceived the app as useful, and how they made use of the app to help them understand anatomy and anatomical relationships. At the beginning of the semester surveys and questionnaires were conducted to determine students' initial perceptions of the app. Over the course of the semester, students were given a brief lesson on how to use the app, provided with resources within the app, and given quiz questions based on images created in the app. At the end of the semester surveys, questionnaires and interviews were again conducted to determine of students' perceptions of the app had changed, and to learn how students made use of the app. From the data gathered, students' perception of the app was positive to begin, and became slightly more positive over the course of the semester. Having a brief lesson on how to use the app, and exploring the tools available in the app made a significant difference in the students' comfort with the app. The flexibility of the app to be used when and where they wanted, and the ability to adapt the app to their current study practices were some of the app's greatest strengths according to the students. Complete Anatomy is a powerful, flexible 3D app that students perceive as useful, and in some cases even necessary. Having the ability to work at times and in ways they prefer makes it an app that benefits student learning.Item Modeling the effects of flare energy release and transport through chromospheric condensation and ultraviolet coronal emission(Montana State University - Bozeman, College of Letters & Science, 2022) Ashfield, William Henry, IV; Chairperson, Graduate Committee: Dana W. Longcope; This is a manuscript style paper that includes co-authored chapters.Solar flares arise from the release of magnetic free energy through reconnection. A fraction of this energy travels from the corona to the lower solar atmosphere, heating the plasma and driving downflows -- chromospheric condensations -- critical to our understanding of flare energetics. While flare models with impulsive energy injections have successfully reproduced observed chromospheric responses, they typically focus on heating via electron beam deposition, neglecting other modes of energy transport. Observations of long-duration coronal emission in the extreme ultraviolet have further indicated a two-phase energy release process: impulsive energy deposition followed by persistent low-rate heating. As flare energy release and transport are measured by the indirect signatures of condensation and coronal emissions, flare models must account for these phenomena' behavior to infer the characteristics of reconnection. We first investigated the chromospheric response to a constant flare energy flux using a thermal flare model driven by in-situ coronal heating. An analytical expression for the condensation velocity was developed and found to be well described by the observed characteristic properties, allowing condensation to serve as a diagnostic for both the energy flux at the reconnection site and the pre-flare density scale height of the chromosphere. These results were tested on condensations observed in Si IV 1403 ?A spectral line redshifts. A Gaussian heating profile, inferred from footpoint UV emission corresponding to the measured downflows, was used to drive a one-dimensional simulation from which Si IV spectra were synthesized. Although the synthetic velocity evolution agreed reasonably well with observation, thus providing evidence for our model's validity, the condensation's timescale was found to be independent of the time scale of the energy release. To address coronal EUV emission signatures, long-duration flare heating was modeled through the slow dissipation of turbulent Alfven waves. Motivated by observations of supra-arcade downflows, the waves were initiated by retracting newly-reconnected flux tubes through a current sheet and dissipated through their non-linear interaction. EUV lightcurves synthesized from simulation results reproduced emissions that decayed in 40 minutes. This model, created self-consistently from reconnection-powered flare energy release, offers a possible explanation for the outstanding problem of persistent flare emission.Item Implementing INACSL standardized simulation to improve NCLEX scores(Montana State University - Bozeman, College of Nursing, 2022) Poole, Joseph David; Chairperson, Graduate Committee: Denise RiveraThe current nursing shortage further worsens every time a new nurse fails the National Council Licensure Examination (NCLEX-RN) exam. Simulation education presents a possible solution to better prepare nursing students for licensure and professional practice. This project aims to demonstrate how nursing schools can improve NCLEX-RN first attempt pass rates by adhering to INACSL simulation standards and improving clinical judgment. Seminal research by the National Council of State Boards of Nursing (NCSBN) found no statistical difference when nursing schools substituted 50% of bedside clinical time with simulation experiences. The International Nursing Association of Clinical and Simulation Learning (INACSL) created standards of simulation which were adhered to for the previous study. While no specific causal research proves INACSL standards-based simulation training improves NCLEX-RN pass rates, adjacent literature demonstrates simulation learning engages students and improves clinical judgment. The first methodology step in this project proposal establishes a foundation of understanding amongst all nursing education faculty regarding the nine INACSL standards for simulation by conducting a brief webinar. Further training focuses on a tiered approach for educators, explicitly teaching clinical, skills, and simulation. This next tier of faculty would attend a one-day Gateway Debriefing Workshop which briefly trains enhanced simulation debriefing skills. The highest level of simulation-specific instructors will complete a five-day Healthcare Simulation Essentials Course that provides intensive training in simulation theory and debriefing skills for simulation educators. The Debriefing Assessment for Simulation in Healthcare (DASH) tools facilitate the evaluation of project influenced changes and enhance debriefing excellence by utilizing the DASH rater tool. The results of this project proposal are pending execution. Outcomes expected include increased DASH rater evaluations of simulation faculty and improved NCLEX-RN first attempt pass rates up to 100%. Conclusions derived from investigations of this project proposal support INACSL simulation standards adherence enhances simulation outcomes and leads to improved NCLEX-RN first attempt pass rates.Item How does the use of the anatomage table impact student learning of anatomy and physiology concepts?(Montana State University - Bozeman, College of Letters & Science, 2021) Keegan, Emily; Chairperson, Graduate Committee: Greg FrancisAnatomy and Physiology is a class that relies heavily on visual models. In this study, the use of the Anatomage table was used during the skeletal system and muscular system units. A comparison group did not use the table for their lab in the first unit, and an experimental group used the table. During the second unit, the groups switched so that all students got to experience working with the table in at least one unit. Pre and post-test data, surveys, interviews, and retention tests were used as data collection tools. The results suggest that the Anatomage table has benefits for some students, especially in identifying and applying the knowledge acquired in the units. It had less of an impact on written test scores, especially in higher achieving students.Item Resilience assessment of active distribution networks(Montana State University - Bozeman, College of Engineering, 2021) Miller, Ryan Jared Alexander; Chairperson, Graduate Committee: Maryam BahramipanahPower system resilience focuses on a system's ability to prepare for and recover from events which would severely degrade its performance. With severe weather events and regional disasters such as hurricanes, polar vortex cold, and wildfires increasing in frequency and intensity in recent years, work toward simulation and quantification techniques of power system resilience is more necessary than ever. To generate a realistic model, this work produces a geographic topography to geographically lay out and test power system. Furthermore, different extreme events such as flooding, hurricanes, wildfires, and tornadoes are modeled, and the proposed technique evaluates their impacts on the power system degradation and resilience. The availability of recovery resources and several stochastic recovery dynamics that modify the system's depth of degradation and recovery profile during repair time are studied in this work. Multiple resilience metrics are proposed to aid in analyzing the system's recovery performance. The performance of this proposed technique is then evaluated for a flood of intermediate intensity which causes component failures and system outages within the grid. System recovery resources are varied by adjusting the number of crews who can simultaneously repair the system. Resilience indices are evaluated, and it is shown that with increasing availability of repair crews and recovery resources, the system resilience improves. The proposed strategy can be applied to an arbitrary test system with ease. Different strategies such as energy storage management and repair prioritization can be modified in future works to test potential improvements or optimizations for a given test system under the occurrence of a specific extreme event.Item Climate-fire-vegetation dynamics in the Greater Yellowstone Ecosystem: recent trends and future projections in a changing climate(Montana State University - Bozeman, College of Letters & Science, 2020) Emmett, Kristen Dawn; Co-chairs, Graduate Committee: Benjamin Poulter and David Roberts; Katherine M. Renwick and Benjamin Poulter were co-authors of the article, 'Disdentangling climate and disturbance effects on regional vegetation greening trends' in the journal 'Ecosystems' which is contained within this dissertation.; Katherine M. Renwick and Benjamin Poulter were co-authors of the article, 'Adapting a dynamic vegetation model for regional biomass, plant biogeography, and fire modeling in the western U.S.: evaluating LPJ-GUESSLMFIRECF' submitted to the journal 'Ecological modelling' which is contained within this dissertation.; Benjamin Poulter was a co-author of the article, 'Processed-based modeling approaches for climate-vegetation-fire feedbacks in the Greater Yellowstone Ecosystem' which is contained within this dissertation.Climate change threatens to change forested ecosystems and wildfire characteristics across the globe. For the Greater Yellowstone Ecosystem (GYE), under future warming temperatures, wildfire activity is expected to increase and the suitable habitat for many dominant tree species is expected to shrink. Previous studies predict large high severity fires to occur more frequently, potentially so frequent that forests are unable to grow old enough to produce seeds and self-regenerate. Studies of suitable climate spaces show that previously habitable areas may become too warm or dry to support common GYE trees. The first goal of this dissertation was to use vegetation images from satellites to detect recent changes in forest productivity in the GYE, and then determine the relative importance of recent climate and disturbance observations in explaining these changes. We found that areas with detected increases in plant growth, or 'greening' trends, were associated with forested areas regenerating after wildfire. Detected decreases in plant growth, or 'browning' trends, were associated with areas that had recently burned. Historically dry areas with recent increases in precipitation were associated with greening trends. Warming of 0-2 °C was associated with greening trends, while greater increases in temperature (>2 °C) were correlated with browning trends. The key take-away is although forests in the GYE are usually considered temperature limited, changes in precipitation may be more important than previously thought. The second goal of this dissertation was to adapt a global vegetation computer model for regional applications to simulate forests and wildfire dynamics, ultimately to run simulations under future climate conditions to predict how forest extent and composition may change. Life history characteristics and climate limitations were aquired for the dominant GYE plant types to dictate their establishment, growth, competition, and mortality in the new model. Before running future simulations, it is required to evaluate how well the model represents current conditions. Adding new equations that calculate the initiation, spread, and effects of crown fires was required to reproduce recent vegetation abundance, distribution of plant types, and fire activity in the GYE. Methods, expected results, and implications of running future simulations are described in Chapter 4.Item Analysis of complex samples by mass spectrometry leads to insights into system dynamics(Montana State University - Bozeman, College of Letters & Science, 2021) Peach, Jesse Thomas; Chairperson, Graduate Committee: Brian Bothner; James Larson, Sutton Kanta, Eric Boltinghouse, Rebecca Mueller, Ganesh Balasubramanian, Mohammed Refai, Brent Peyton and Brian Bothner were co-authors of the article, 'Optimization of thermal small molecule and protein mass spectrometry analysis' submitted to the journal 'Analytical biochemistry' which is contained within this dissertation.; Rebecca Mueller, Dana Skorupa, Margaux Mesle, Sutton Kanta, Eric Boltinghouse, Bailey Sharon, Valerie Copie, Brian Bothner and Brent Peyton were co-authors of the article, 'Longitudinal meta-analysis of the Five Sisters Hot Springs in Yellowstone National Park reveals a dynamic thermoalkaline environment' submitted to the journal 'Environmental microbiology' which is contained within this dissertation.; Stephanie M. Wilson, Logan D. Gunderson, Lizzi Frothingham, Tan Tran, Seth T. Walk, Carl J. Yeoman, Brian Bothner and Mary P. Miles were co-authors of the article, 'Temporal metabolic response yields a dynamic biosignature of inflammation' submitted to the journal 'iScience' which is contained within this dissertation.Systems biology offers a holistic approach to biological science. In its most complete form, systems biology requires comprehensive data encompassing all of the parts or molecules across a set of hierarchical networks. To obtain and analyze the comprehensive and large datasets required for systems biology analysis, biologists have taken advantage of new technology and computational tools. Over the last few decades, advances in computational modeling and analysis technology has dramatically increased the efficacy of systems biology and the understanding of the natural world. However, systems biology is still an emerging discipline. The overwhelming scale of potential biological data that has yet to be described, coupled with interpretation and application obstacles, leaves much work to be accomplished. One aspect of systems biology that needs development is the interpretation and analysis of temporal biological data. Temporal data reveals more about biological phenomena than static data as biology is inherently dynamic. This dissertation explores the benefits of temporal profiling of complex samples to make time-resolved conclusions about complicated biological questions. Three research projects are the backbone of this document, with a chapter being devoted to each. Chapter 2 describes the development of a comprehensive method for extraction and mass spectrometry analysis of several different fractions from hot spring sediment. Chapter 3 delves into a multi-omics analysis tracking changes over the course of three years in a thermoalkaline spring system in Yellowstone National Park. It defines how specific extracellular small molecules correlate with microbial fitness. Specifically, how unique nitrogen and sulfur containing molecules in the sediment drive archaeal abundance and diversity. The final chapter introduces the concept of a 'dynamic biosignature', a set of metabolites that have similar responses to known biomarkers, in this case pro-inflammatory cytokines. A cohort of metabolites was identified that provided mechanistic insight into the inflammatory response. Overall, this dissertation provides examples of systems biology analysis and provides evidence that static, single time-point datasets fail to capture that which is the essence of biology - change.