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Thermomechanical Process Simulation And Quantification Of Nanoscale Precipitation Influencing Ductility And Strength During Alloy Processing, Alyssa Stubbers

Theses and Dissertations--Chemical and Materials Engineering

Experimental process simulation and quantification of microstructure development during processing are challenging due to limitations with machinery temperature capability, inadequate resolution and sampling volume of currently available characterization techniques, and difficulty characterizing material microstructures as close to processing-relevant conditions as possible. This dissertation addresses how process simulation can be performed using Gleeble thermomechanical technologies and how microstructure development during these processing simulations can be quantified both in-situ and ex-situ.

The first portion of this dissertation demonstrates how Gleeble technologies can be applied to simulate complex material processing conditions in order to produce process-property profiles that can be used to inform …

Advanced Microstructural Characterization Of Functionally Graded Dental Ceramic Material For Materials-Informed Finishing, Angani Vigneswaran

Theses and Dissertations--Manufacturing Systems Engineering

Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) has gained popularity as the choice of material for dental prosthetics. Ivoclar Vivadent’s IPS e.max ZirCAD Prime dental ceramic incorporates a unique gradient technology that varies the yttria content over the thickness of the material. The top layer is composed of 5Y-TZP which is desired for its optical properties while the bottom layer is composed of a much stronger 3Y-TZP. In between the two layers, 5Y-TZP and 3Y-TZP are mixed to form a transition layer. Varying the amount of yttria allows for more esthetically pleasing translucency in the visible areas of the restoration without compromising …

Anisotropic Material Behavior Of 3d Printed Fiber Composites, Jordan Garcia

Theses and Dissertations--Mechanical Engineering

Literature has shown that 3D printed composites may have highly anisotropic mechanical properties due to variation in microstructure as a result of filament deposition process. Laminate composite theory, which is already used for composite products, has been proposed as an effective method for quantifying these mechanical characteristics. Starting with the analysis of comparing the printing orientation of premanufactured carbon fiber reinforced filament, the mechanical properties of 3D printed objects were examined. The mechanical properties changed not only as a result of machine choice, but how the sample is oriented along the printing bed. The analysis continued with looking at the …

Mechanical Energy Harvester For Powering Rfid Systems Components: Modeling, Analysis, Optimization And Design, Alireza Babaei

Theses and Dissertations--Mechanical Engineering

Finding alternative power sources has been an important topic of study worldwide. It is vital to find substitutes for finite fossil fuels. Such substitutes may be termed renewable energy sources and infinite supplies. Such limitless sources are derived from ambient energy like wind energy, solar energy, sea waves energy; on the other hand, smart cities megaprojects have been receiving enormous amounts of funding to transition our lives into smart lives. Smart cities heavily rely on smart devices and electronics, which utilize small amounts of energy to run. Using batteries as the power source for such smart devices imposes environmental and …

Utilization Of Uncrewed Aircraft Systems Towards Investigating The Structure Of The Atmospheric Surface Layer, Loiy Al-Ghussain

Theses and Dissertations--Mechanical Engineering

This study presents two approaches to investigate the surface-layer structure during the morning transition using uncrewed aircraft systems. The first approach employs three uncrewed aircraft systems- each equipped with a single multi-hole probe- simultaneously measuring horizontal transects were partnered with a fourth measuring vertical profiles during two consecutive mornings as part of the 2017 Collaboration Leading Operational Unmanned Aerial System Development for Meteorology and Atmospheric Physics (CLOUDMAP) measurement campaign near Stillwater, Oklahoma, U.S.A. Data were analyzed to extract time-dependent single-point statistics of kinematic and thermodynamic variables from the uncrewed aircraft systems. In addition, an approach is presented by which multi-point …

Multiscale Modeling Of Cardiac Growth And Baroreflex Control, Hossein Sharifi

Theses and Dissertations--Mechanical Engineering

The heart functions within a complex system that adapts its function to any alteration in loading via several mechanisms. For example, the baroreflex is a short-term feedback loop that modulates the heart's function on a beat-to-beat basis to control arterial pressure. On the other hand, cardiac growth is a long-term adaptive response that occurs over weeks or months in response to changes in left ventricular loading. Understanding the mechanisms that drive ventricular growth and biological remodeling is critical to improving patient care. Multiscale models of the cardiovascular system have emerged as effective tools for investigating G&R, offering the ability to …

Impact Of Spallation And Internal Radiation On Fibrous Ablative Materials, Raghava Sai Chaitanya Davuluri

Theses and Dissertations--Mechanical Engineering

Space vehicles are equipped with Thermal Protection Systems (TPS) that encounter high heat rates and protect the payload while entering a planetary atmosphere. For most missions that interest NASA, ablative materials are used as TPS. These materials undergo several mass and energy transfer mechanisms to absorb intense heat. The size and construction of the TPS are based on the composition of the planetary atmosphere and the impact of various ablative mechanisms on the flow field and the material. Therefore, it is essential to quantify the rates of different ablative phenomena to model TPS accurately. In this work, the impact of …

A Computational Fluid Dynamic Analysis Of Oxyacetylene Combustion Flow For Use In Material Response Boundary Conditions, Craig Meade

Theses and Dissertations--Mechanical Engineering

Oxyacetylene torches are used in the aerospace industry and research to test thermal protection system materials (TPS) due to their high flame temperatures and high heat flux capabilities. The purpose of this work is to determine a combustion model to accurately simulate the high temperature flow of an oxyacetylene torch. The flow conditions around a sample material can then be used as boundary conditions when modeling TPS material response. Two separate combustion models with equilibrium chemistry were investigated using ANSYS Fluent™; the Eddy-Dissipation Model, and the Partially Premixed model.The results of this study are compared to existing experiments for validation.

A Cfd-Based Scaling Analysis On Liquid And Paint Droplets Moving Through A Weak Concurrent Airflow Stream, Masoud Arabghahestani, Nelson Akafuah, Tianxiang Li, Kozo Saito

Progress in Scale Modeling, an International Journal

We conducted volume of fluids (VOF) multiphase model numerical simulations to obtain the interaction among all the major governing forces identified in our previous paper. Our numerical experiments are intended to assess the droplet generation process and the jetting behavior by providing specific input conditions, offering CFD as a tool to study scaling correlations instead of physical experiments. Water droplets that can represent waterborne paints were generated by piezo-generated sinusoidal waveforms at the inlet of the nozzle. The governing forces included the external piezo-based wave-generation force, the inertial force of droplets, the inertial force of air, the viscose force of …

Challenges & Pragmatic Solutions For The Design And Construction Of A 300-Acre Ccr Landfill Located In The Southwestern Us - A Case Study, Andy Lucas, Jason Pokorny

World of Coal Ash Proceedings

No abstract provided.

Geochemical Explanations For Strong Natural Attenuation Of Molybdenum, Selenium, And Lithium In A Groundwater Plume, Jacob Chu, J. P. Brandenburg

World of Coal Ash Proceedings

No abstract provided.

Ccr Beneficial Use Data Capture And Reporting, Joe Ploetz, Kevin Foody

World of Coal Ash Proceedings

No abstract provided.

The Intersection Of The Ccr Rule, Superfund, And Irrigation On The Great Plains, Shane D. Mcdonald, Jillian Troyer, Robert Kleinmann, Marty Stange

World of Coal Ash Proceedings

No abstract provided.

Attenuation And Source Zone Depletion Of Boron From Coal Combustion Residuals In Groundwater, J.P. Brandenburg, Dave Hagen

World of Coal Ash Proceedings

No abstract provided.

Whole Effluent Toxicity (Wet) Assessments And Experimental Considerations For Evaluating Coagulation Agents And Polymers For Wastewater Treatment Of Coal Combustion Products, Konrad J. Kulacki, William L. Goodfellow Jr., Margaret L. Fleming, Alexandra N. Steele

World of Coal Ash Proceedings

No abstract provided.

Geostructural Construction In Ash: An Update On The Largest Geostructural Work To Date, Anthony Sak, Ryan T. Smith

World of Coal Ash Proceedings

No abstract provided.

Benefits Of Numerical Flow And Transport Modeling Applied To Ccr Site Characterization, Remedial Design, And Closure, Johnathan F. Ebenhack, Eric M. Hicks

World of Coal Ash Proceedings

No abstract provided.

Monitoring Of Construction Over Soft Ccr Deposits, Pedro J. Amaya, Michelle Perez-Canals, Mary Nodine, Will G. Lukas

World of Coal Ash Proceedings

No abstract provided.

Groundwater Monitoring Plan Considerations For Assessment And Corrective Action Sites, Sherren Clark, Nicole Kron, Tom Karwoski, Bernd Rehm

World of Coal Ash Proceedings

No abstract provided.

Evaluation Of Remedial Actions At Coal Combustion Residuals (Ccr) Sites Through Coupled Hydrogeological-Geochemical Reactive Transport Modeling, Pj Nolan, William Deutsch, Greg Lehn, Rens Verburg

World of Coal Ash Proceedings

No abstract provided.

Evaluation Of Methods To Differentiate Ccr From Native Soil Or Fill With Similar Visual/Physical Characteristics To Successfully Facilitate Ccr Removal, Trenton M. Godwin, Stephen K. Wilson, Kevin M. Stephenson

World of Coal Ash Proceedings

No abstract provided.

Smart Technology To Identify Leaks And Enhance Pipeline Safety, Cory Solyom

World of Coal Ash Proceedings

No abstract provided.

Reducing The Cost Of Wastewater Treatment From Coal Ash Basin Closure Projects Using Closed Loop Zero Valent Iron Treatment Methods, Madan Tandukar, Alex Korff, Andrew Vincent, Chris Hardin

World of Coal Ash Proceedings

No abstract provided.

Selen-Ix™ Applied To Coal Ash Pond Clean-Up, Brent Baker, Veneil Sundar, Alex Soto

World of Coal Ash Proceedings

No abstract provided.

Sono-Processing Of Coal For Removal Of Ash And Other Impurities, Ramamurthy Nagarajan

World of Coal Ash Proceedings

No abstract provided.

Ibutton Thermocon: Economically Measure Mortar Temperature Generation To Estimate Time Of Set, Carl Howard

World of Coal Ash Proceedings

No abstract provided.

Mse Berm: Overcome Site Constraints And Maximize Air Space, Johnny Lowe, Jason Thaxton

World of Coal Ash Proceedings

No abstract provided.

Polymer-Free Geosynthetic Clay Liner For Containment Of Aggressive Leachates, Trevor Walker, Stefan Niewerth

World of Coal Ash Proceedings

No abstract provided.

Pre-Design Bench-Scale Evaluation Of The Effectiveness Of Ash Pond Closure In Place Using In-Situ Soil Stabilization, Marc B. Okin, Jeffery A. Miller, William J. Haswell, Sonya Burns

World of Coal Ash Proceedings

No abstract provided.

Ccr Removal And Its Effects On Soil And Groundwater Geochemistry, Sarah Holmstrom, Clint Miller

World of Coal Ash Proceedings

No abstract provided.