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2018

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Development Of A Rapid Fatigue Life Testing Method For Reliability Assessment Of Flip-Chip Solder Interconnects, Cody Jackson Marbut Dec 2018

Development Of A Rapid Fatigue Life Testing Method For Reliability Assessment Of Flip-Chip Solder Interconnects, Cody Jackson Marbut

Graduate Theses and Dissertations

The underlying physics of failure are critical in assessing the long term reliability of power packages in their intended field applications, yet traditional reliability determination methods are largely inadequate when considering thermomechanical failures. With current reliability determination methods, long test durations, high costs, and a conglomerate of concurrent reliability degrading threat factors make effective understanding of device reliability difficult and expensive. In this work, an alternative reliability testing apparatus and associated protocol was developed to address these concerns; targeting rapid testing times with minimal cost while preserving fatigue life prediction accuracy. Two test stands were fabricated to evaluate device reliability …

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On The Development Of 8,000 Psi Geopolymer Mortar For Practical Use In Field Applications, Remington Gabriel Reed Dec 2018

On The Development Of 8,000 Psi Geopolymer Mortar For Practical Use In Field Applications, Remington Gabriel Reed

Graduate Theses and Dissertations

Although there are several perceived benefits from the use of geopolymer binder as an alternative to ordinary portland cement in concrete materials, it is not widely used in field applications. Geopolymer materials have no set guidelines for mixture design and often require heat curing to facilitate strength gain. Additionally, many geopolymers are created using carefully controlled and high quality materials and activator chemicals. These factors greatly affect the practicality of the material. The goal of this research was to create a geopolymer material capable of achieving high compressive strengths at 28 days without heat curing, and using only readily available …

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Developing Ultra-High Performance Concrete (Uhpc) With Locally Available Materials, Ali Alsalman Dec 2018

Developing Ultra-High Performance Concrete (Uhpc) With Locally Available Materials, Ali Alsalman

Graduate Theses and Dissertations

Ultra-High Performance Concrete (UHPC) can enhance the durability and resilience of concrete structures. The use of local materials is a fundamental step to save energy and reduce the cost of concrete. The main focus of this research was to develop a UHPC with compressive strength of 150 MPa using locally sources materials. In this study, the effect of fine materials, binder type and content, type of mixer, steel fibers and curing regimes on concrete’s compressive strength were investigated. The relationship between compressive strength and elastic modulus was also studied. This study synthesizes all relevant experimental data in the literature to …

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Towards Environmentally Sustainable And Cost-Effective Food Distribution In The U.S., Jasmina Burek Dec 2018

Towards Environmentally Sustainable And Cost-Effective Food Distribution In The U.S., Jasmina Burek

Graduate Theses and Dissertations

Distribution centers (DCs) and supermarkets have an important role in food sustainability, but no previous research has accounted for their environmental impact. The purpose of this research was to assess environmental sustainability of grocery, perishables, and general merchandise DCs; to estimate food storing and retailing impact; and to provide cost-effective strategies to reduce DCs’ environmental impacts. The importance and relevance of the research is threefold: improving sustainability of DCs, food storing, and food retailing. The main method used in this research was the life cycle assessment (LCA) method. An initial study calculated environmental impacts of the Wal-Mart Stores, Inc. DCs, …

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Effect Of Continuity Plate Eccentricity On The Performance Of Welded Beam-To-Column Connections, Jason Thomas Norwood Dec 2018

Effect Of Continuity Plate Eccentricity On The Performance Of Welded Beam-To-Column Connections, Jason Thomas Norwood

Graduate Theses and Dissertations

Beam-to-column connections in structural steel buildings may have varying degrees of rotational restraint and varying degrees of moment transfer. In fully restrained moment connections, shear is typically transferred through the beam web, while the moment is mostly transferred through the beam flanges which create tension/compression force couples. Column sections that are incapable of resisting these flange forces are often retrofitted with continuity plates within the connection region to improve capacity. In cases of unequal beam depths on either side of the column, an eccentricity between the framed-in beam flange and continuity plate may be required; however, limited research exists to …

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Effect Of Cement Content On Concrete Performance, Caleb Joshua Lebow Dec 2018

Effect Of Cement Content On Concrete Performance, Caleb Joshua Lebow

Graduate Theses and Dissertations

Of all the traditional concrete materials, portland cement has the greatest impact on mixture cost and the environment. Cement is in many ways the glue holding concrete together (Weiss, 1999), and as such, it plays a major role in fresh and hardened concrete properties. Without the proper range of cement in the mixture, low strength development or excessive shrinkage may occur leading to premature deterioration. The Arkansas Department of Transportation (ARDOT) recognizes two types of concrete for use in bridge construction, Class S and Class S(AE). This paper focuses on the findings from testing of Class S(AE) concrete, short for …

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Utilizing 3d Printed Analogue Soils To Investigate Specimen Size Effects In Triaxial Testing, Claire Louise Stewart Dec 2018

Utilizing 3d Printed Analogue Soils To Investigate Specimen Size Effects In Triaxial Testing, Claire Louise Stewart

Graduate Theses and Dissertations

Triaxial testing is one of the fundamental laboratory tests used in geotechnical engineering to determine strength parameters, such as shear strength and friction angle. Investigating the minimum representative elementary volume (REV) can verify the independence of size effects on strength parameters and ensure that the scaled laboratory tests results are consistent, repeatable, and representative of field conditions. Although, REV has been studied for many applications, there is disagreement within geotechnical engineering of a minimum particle diameter to specimen diameter to minimize the size effects related to the REV in consolidated drained (CD) triaxial tests. This research study compared the strength …

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Assessing Biofiltration Without Ozonation For Removal Of Trihalomethane Precursors In Drinking Water At The Beaver Water District Drinking Water Treatment Plant, Sana Ajaz Dec 2018

Assessing Biofiltration Without Ozonation For Removal Of Trihalomethane Precursors In Drinking Water At The Beaver Water District Drinking Water Treatment Plant, Sana Ajaz

Graduate Theses and Dissertations

Biofiltration without pre-ozonation has the capability to remove natural organic matter (NOM) fractions that serve as precursors of disinfection byproducts (DBPs), which include the four regulated trihalomethanes (THMs) and dichloroacetonitrile (DCAN). Rapid small-scale column tests (RSSCTs) and Pilot Plant filters operated at empty-bed contact times (EBCTs) of 4, 8, and 16 minutes were used to evaluate the performance of nutrient-amended (free ammonia and phosphorus) biofiltration for THM and DCAN precursor removal, as measured using formation potential (FP) tests. NOM surrogates – which include dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA254) and fluorescence-PARAFAC components – were measured weekly throughout the …

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Clemson Commencement Program,December 2018, Clemson University Dec 2018

Clemson Commencement Program,December 2018, Clemson University

Clemson Commencement Programs

No abstract provided.

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A Comparison Of Saxophone Mouthpieces Using Fourier Analysis To Quantify Perceived Timbre, Mark Robert Pipes Dec 2018

A Comparison Of Saxophone Mouthpieces Using Fourier Analysis To Quantify Perceived Timbre, Mark Robert Pipes

Dissertations

The saxophone mouthpiece significantly contributes to the overall timbre of the instrument. Specialized mouthpiece designs employ combinations of chamber shape, facing dimensions, and material to create a potential sound and response for the performer. Also, manufacturers claim that ligatures affect tonal brightness. However, there is a lack of scientific data reflecting the impact of the claimed tonal characteristics of the specified designs on timbre. With the advent of the smartphone application, the spectrum analysis (also known as impedance spectra) resulting from a Fourier Transform has recently become available to a mass audience. This technology is being investigated to quantify timbre …

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Science Café | Detecting Deception, Dec. 5, Ohio University College Of Arts & Sciences Dec 2018

Science Café | Detecting Deception, Dec. 5, Ohio University College Of Arts & Sciences

All Forum Articles

No abstract provided.

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Study Of Transport Of Nanoparticles With K-L Model Through A Stenosed Microvessels, Rekha Bali, Nivedita Gupta Dec 2018

Study Of Transport Of Nanoparticles With K-L Model Through A Stenosed Microvessels, Rekha Bali, Nivedita Gupta

Applications and Applied Mathematics: An International Journal (AAM)

This paper studies a constitutive equation for blood with the transport of nanoparticles in a stenosed microvessel. The flow of blood through a bell-shaped stenosed micro blood vessel has been investigated with an importance of permeable walls that treats blood as non-Newtonian fluid by using K-L model. This model is more appropriate than other non-Newtonian models because K-L model involve three parameters such as plasma viscosity, yield stress and one other chemical variable while casson model involves only one parameter i.e. yield stress. In the present paper, the effective longitudinal diffusion of nanoparticles has been studied in stenosed blood vessel …

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Applications Of Passive Solar Energy And Reclaimed Heat From Livestock Manure Decomposition, Naomi Elizabeth Schalle Dec 2018

Applications Of Passive Solar Energy And Reclaimed Heat From Livestock Manure Decomposition, Naomi Elizabeth Schalle

Honors Theses

One energy intensive part of raising livestock in colder climates is keeping water warm and easily accessible to the animals in the winter. The objective of this project is to increase the sustainability of livestock farms by developing and implementing an energy conservation measure to decrease electric energy usage on the heating of water for livestock in the winter. One thing farmers have in excess is manure, an abundant and renewable resource for the farmers. This project will capitalize on that excess to encourage a creative use of resources often seen as waste, through implementing aspects of sustainability and conservation …

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University Of Dayton Magazine, Winter 2018-19, University Of Dayton Dec 2018

University Of Dayton Magazine, Winter 2018-19, University Of Dayton

University of Dayton Alumni Publications

The University of Dayton Magazine is published quarterly by the Office of University Marketing and Communications for alumni, parents, students, faculty/staff, trustees and other friends of UD. Articles in this issue include "Funkadelic Dayton," "Dan Curran: Grateful for the Gift of Life," "Restoring the Christmas Spirit," and "Lessons Learned: Reflections on a Life Acquired in and out of the Classroom," along with regular features (President's Commentary, Conversation Pieces, Letters, Commentary, View Finder, Where are you Reading?, Sports, Class Notes, Perceptions, Parting Words, and Connections).

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Deepsign: A Deep-Learning Architecture For Sign Language, Jai Amrish Shah Dec 2018

Deepsign: A Deep-Learning Architecture For Sign Language, Jai Amrish Shah

Computer Science and Engineering Theses - Archive

Sign languages are used by deaf people for communication. In sign languages, humans use hand gestures, body, facial expressions and movements to convey meaning. Humans can easily learn and understand sign languages, but automatic sign language recognition for machines is a challenging task. Using recent advances in the field of deep-learning, we introduce a fully automated deep-learning architecture for isolated sign language recognition. Our architecture tries to address three problems: 1) Satisfactory accuracy with limited data samples 2) Reducing chances of over-fitting when the data is limited 3) Automating recognition of isolated signs. Our architecture uses deep convolutional encoder-decoder architecture …

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Classification Of Clinical Narratives Using Convolutional Neural Network, Nikit Rajiv Lonari Dec 2018

Classification Of Clinical Narratives Using Convolutional Neural Network, Nikit Rajiv Lonari

Computer Science and Engineering Theses - Archive

Patient safety is a key aspect for good consumer care. When an individual is hospitalized or receives medication the family wants the patient safety to be above all factors. For instance, a drug can do both either cure the disease or perhaps, give rise to an adverse event. A drug administered for an indicated condition has substantial power to reduce or cure a disease and further to prevent it from happening again in the future but at the risk of side effects. At present, there are several methods in patient safety and in particular in the area of signal detection …

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Towards End-To-End Semi-Supervised Deep Learning For Drug Discovery, Xiaoyu Zhang Dec 2018

Towards End-To-End Semi-Supervised Deep Learning For Drug Discovery, Xiaoyu Zhang

Computer Science and Engineering Theses - Archive

Observing the recent progress in Deep Learning, the employment of AI is surging to accelerate drug discovery and cut R&D costs in the last few years. However, the success of deep learning is attributed to large-scale clean high-quality labeled data, which is generally unavailable in drug discovery practices. In this thesis, we address this issue by proposing an end-to-end deep learning framework in a semi supervised learning fashion. That is said, the proposed deep learning approach can utilize both labeled and unlabeled data. While labeled data is of very limited availability, the amount of available unlabeled data is generally huge. …

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Dwrelu : Double Weighted Rectifier Linear Unit An Activation Function With Trainable Scaling Parameter, Bhaskar Chandra Trivedi Dec 2018

Dwrelu : Double Weighted Rectifier Linear Unit An Activation Function With Trainable Scaling Parameter, Bhaskar Chandra Trivedi

Computer Science and Engineering Theses - Archive

Deep Neural Network have become very popular for computer vision application in recent years. At the same time, it remains important to understand the different implementation choices that need to be made when designing a neural network and to thoroughly investigate existing and novel alternatives for those choices. One of those choices is the activation function. The ReLU activation function is a widely used activation function. It discards all the values below zero and keeps the ones greater than zero. Variations such as Leaky ReLU and Parametric ReLU do not discard values, so that gradiants are nonzero for the entire …

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Health Monitoring Of Atlas Data Center Clusters And Failure Analysis, Meenakshi Balasubramanian Dec 2018

Health Monitoring Of Atlas Data Center Clusters And Failure Analysis, Meenakshi Balasubramanian

Computer Science and Engineering Theses - Archive

Monitoring the health of data center clusters is an integral part of any industrial facility. ATLAS is one of the High Energy Physics experiments at the Large Hadron Collider (LHC) at CERN. ATLAS DDM (Distributed Data Management) is a system that manages data transfer, staging, deletions and experimental data on the LHC grid. Currently, the DDM system relies on Rucio software, with Cloud based object storage and No-SQL solutions. It is a cumbersome process in the current system, to fetch and analyze the transfer, staging and deletion metrics of a specific site for any regional center. In this thesis, a …

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Monitoring Of Swt2 Data Clusters For The Atlas Experiment, Antara Ray Dec 2018

Monitoring Of Swt2 Data Clusters For The Atlas Experiment, Antara Ray

Computer Science and Engineering Theses - Archive

Monitoring of the South West Tier 2 RSEs is done by CERN with the help of Rucio. The challenge faced by the team monitoring the servers at the University of Texas site was that the monitoring data is pictorially represented and provided to them in GIF format. In this work we focus on creating an interactive site that will not only monitor the data at the local RSEs but also create a platform to analyze the data storage systems. It turn it will also create alerts whenever during monitoring an aberration from expected behavior is noticed either in the storage …

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Topological And Feature Based Identification Of Hole Boundaries In Point Cloud Data And Differentiation Between Surface And Physical Holes, Aaqif Muhtasim Dec 2018

Topological And Feature Based Identification Of Hole Boundaries In Point Cloud Data And Differentiation Between Surface And Physical Holes, Aaqif Muhtasim

Computer Science and Engineering Theses - Archive

With the advent of autonomous agents becoming prominent in everyday lives, the importance of processing the surroundings into understandable features becomes more and more important. 3D point clouds play a major role in the perception of such agents and thus having the ability to correctly decipher features from point clouds is crucial to the planning of actions that the agent would need to undertake. This thesis analyzes holes found in point clouds. Based on two approaches that center around topological data analysis and local point set features respectively. It studies how each of the methods works and how a combination …

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Generating An Adaptive Path Using Rrt Sampling And Potential Functions With Directional Nearest Neighbors, Sandeep Chahal Dec 2018

Generating An Adaptive Path Using Rrt Sampling And Potential Functions With Directional Nearest Neighbors, Sandeep Chahal

Computer Science and Engineering Theses - Archive

Planning algorithms have attained omnipresent successes in several fields including robotics, animation, manufacturing, drug design, computational biology and aerospace applications. Path Planning is an essential component for autonomous robots. The problem involves searching the configuration space and constructing a desired collision-free path that connects two states (the start and the goal) for a robot to gradually navigate from one state to another. In global path planners, the complete path is computed prior to the robot set off. Sampling based planning like Rapidly Expanding Random Trees (RRT) and Probabilistic Road Maps (PRM) used for single or multi-query planning has gained popularity …

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Text Mining On Twitter Data To Evaluate Sentiment, Srijanee Niyogi Dec 2018

Text Mining On Twitter Data To Evaluate Sentiment, Srijanee Niyogi

Computer Science and Engineering Theses - Archive

Social media platforms have been a major part of our daily lives. But with the freedom of expression there is no way one can check whether the posts/tweets/expressions are classified on which polarity. Since Twitter is one of the biggest social platforms for microblogging, hence the experiment was done on this platform. There are several topics that are popular over the internet like sports, politics, finance, technology are chosen as the source of the experiment. These tweets were collected over a span of time for more than 2 months via a cron job. Every tweet can be divided into three …

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Nonupdating Methods For The Characterization Of Nonlinear Stress-Strain And Delamination Fracture Properties Of Fiber Reinforced Composites, Bastiaan Corstiaan Van Der Vossen Dec 2018

Nonupdating Methods For The Characterization Of Nonlinear Stress-Strain And Delamination Fracture Properties Of Fiber Reinforced Composites, Bastiaan Corstiaan Van Der Vossen

Mechanical and Aerospace Engineering Dissertations - Archive

Efforts to develop strength and life prediction analysis tools for aircraft composite structures have shown a great need to understand the complexity and interaction of failure modes. Many failure models are highly sensitive to transverse nonlinear shear stress-strain and delamination fracture properties, which are notoriously hard to measure. Without proper input parameters, life predictions analyses will not be successful. The objective of this work was to accurately characterize these mechanical properties of carbon fiber reinforced polymer composites through advanced experimental methods. Full-field noncontact deformation measurements using Digital Image Correlation are used to quantify all surface strains components, enabling the design …

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Evaporative Hotspot Cooling Of Microprocessors Using Electrowetting On Dielectric (Ewod), Arvind Venkatesan Dec 2018

Evaporative Hotspot Cooling Of Microprocessors Using Electrowetting On Dielectric (Ewod), Arvind Venkatesan

Mechanical and Aerospace Engineering Dissertations - Archive

The increased use of smart devices and great strides in fabrication technologies have resulted in densely packed electronics. Combined with 3D packaging, high heat uxes have become the norm. The need for advanced thermal management solutions has risen. Most devices based on their load pro le and architecture are susceptible to non-uniformities in heat uxes. These non-uniformities with very high heat uxes are known as hotspots. Mitigation of hotspots is very important for the normal functioning and long term reliability of microprocessors. Multiple attempts have been made at developing microscale thermal solutions. Most prominent among them are microchannels and heat …

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Design Principles For Large Foil Bearings Based On Scaling Laws: Analyses And Experiment, Srikanth Honavara Prasad Dec 2018

Design Principles For Large Foil Bearings Based On Scaling Laws: Analyses And Experiment, Srikanth Honavara Prasad

Mechanical and Aerospace Engineering Dissertations - Archive

Gas foil bearings are used for supporting high speed turbomachinery systems. They are characterized by complex physical and thermal interactions between the lubricating fluid and the structural elements. Mathematically, the behavior of such systems is governed by nonlinear partial differential equations and pose substantial computational challenges. However, their potential applications in aerospace systems and power generation systems have renewed research and development efforts aimed at simplifying their design and analyses methods. Commercialization of gas foil bearings in Mega Watt scale applications necessitate the development of simple tools for estimating bearing design parameters such as load capacity, radial clearance, and support …

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Surface Roughness Formation During Tensile Plastic Deformation Of Nickel Polycrystals, Kranthi Balusu Dec 2018

Surface Roughness Formation During Tensile Plastic Deformation Of Nickel Polycrystals, Kranthi Balusu

Mechanical and Aerospace Engineering Dissertations - Archive

Understanding the formation of surface roughness could help better diagnose a metal component’s health and could potentially help in making better microstructure design decisions. Both of these, in turn, contribute to the design of efficient structural components. In this work, the research objective is to understand the relationship between the surface microstructure (i.e., grain orientations) and the surface-height changes in nickel polycrystals undergoing small amounts of tensile plastic deformation. The secondary objective is to determine the relationship between surface height and strain localization. Primarily simulations were used, along with experimental surface roughness observations, to validate the simulation results. Discrete dislocation …

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Performance Modeling And Experimental Investigations Of Rotating Detonation Engines, Andrew Ryan Mizener Dec 2018

Performance Modeling And Experimental Investigations Of Rotating Detonation Engines, Andrew Ryan Mizener

Mechanical and Aerospace Engineering Dissertations - Archive

The rotating detonation engine (RDE) is a promising propulsion concept that has the potential to offer increased thermodynamic performance in a compact package with no moving parts. A series of analytical and experimental investigations was carried out on RDEs with the joint goal of investigating swirl, torque, and a range of other design parameters of interest. The model and experimental facility were then applied to related problems with the goal of advancing the understanding of RDE applications. A flexible, low-order, semi-empirical model for a rotating detonation engine was presented. The model was formulated to be able to run broad parametric …

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Direct Numerical Simulation Of Homogeneous Isotropic Turbulence - A Methodology And Applications, Sarah Moussa Hussein Dec 2018

Direct Numerical Simulation Of Homogeneous Isotropic Turbulence - A Methodology And Applications, Sarah Moussa Hussein

Mechanical and Aerospace Engineering Dissertations - Archive

Turbulence has been a topic of scientific research for years. Characterized by unorganized chaotic motion and irregular fluctuations, it persists as one of the most challenging topics in fluid mechanics despite volumes of documented research and crucial findings. This begs the question: What is turbulence and why is it so challenging? Turbulence research studies cover a wide spectrum of branches from fundamental flow propagation to different turbulence interactions. This research project investigates the simplest class of turbulent flow studies, homogeneous isotropic turbulence. In a quest to advance the fundamental understanding of turbulence physics, a direct numerical simulation tool is developed. …

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Observation Of The Interaction Between A Transonic Shock Wave And A Wingtip Vortex||, Troy T. Bushmire Dec 2018

Observation Of The Interaction Between A Transonic Shock Wave And A Wingtip Vortex||, Troy T. Bushmire

Mechanical and Aerospace Engineering Theses - Archive

The present study observes the interaction between two fundamental phenomena in fluid mechanics: the transonic shock wave and the wingtip vortex. While these are two areas of fluid mechanics in which extensive experimental and numerical research has been conducted, there is little information on the interaction between the two. The present study numerically simulates a wing with a NACA-0012 section at Mach 0.758 and observes the interaction between the transonic shock wave and wingtip vortex for various angles of attack. The focus of the study is on the surface flow topology and the flow exterior to the boundary layer. Results …

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