Computational Fluid Dynamics (Cfd) Modeling Of A Laboratory Scale Coal Gasifier, 2013 Georgia Southern University
Computational Fluid Dynamics (Cfd) Modeling Of A Laboratory Scale Coal Gasifier, Kiel S. Schultheiss
Electronic Theses and Dissertations
Furthering gasification technology is an essential part of advancing clean coal technologies. In order to seek insight into the appropriate operations for the formation of synthetic gas (syngas) a numerical simulation was performed to predict the phenomena of coal gasification in a laboratory scale entrained-flow coal gasifier. The mesh for the model was developed with ICEM CFD software and the chemical and physical phenomena were modeled using the fluid flow solver ANSYS FLUENT. Mesh independence was verified. The model was validated with experimental data from several studies performed on a laboratory scale gasifier.
Systematic examination of the model was performed ...
Determination Of Kinetic Parameters From The Thermogravimetric Data Set Of Biomass Samples, 2012 Wroclaw University of Technology
Determination Of Kinetic Parameters From The Thermogravimetric Data Set Of Biomass Samples, Karol Postawa, Wojciech M. Budzianowski
This article describes methods of the determination of kinetic parameters from the thermogravimetric data set of biomass samples. It presents the methodology of the research, description of the needed equipment, and the method of analysis of thermogravimetric data. It describes both methodology of obtaining quantitative data such as kinetic parameters as well as of obtaining qualitative data like the composition of biomass. The study is focused mainly on plant biomass because it is easy in harvesting and preparation. Methodology is shown on the sample containing corn stover which is subsequently pyrolysed. The investigated sample show the kinetic of first order ...
One-Phase Problems For Discontinuous Heat Transfer In Fractal Media, Yang Xiaojun
We first propose the fractal models for the one-phase problems of discontinuous transient heat transfer.The models are taken in sense of local fractional differential operator and used to describe the (dimensionless)melting of fractal solid semi-infinite materials initially at their melt temperatures.
Fast Absolute Quantification Of In Vivo Water And Fat Content With Magnetic Resonance Imaging, 2012 The University of Western Ontario
Fast Absolute Quantification Of In Vivo Water And Fat Content With Magnetic Resonance Imaging, Yifan Cui
Electronic Thesis and Dissertation Repository
Quantitative water fat imaging offers a non-invasive method for monitoring and staging diseases associated with changes in either water or fat content in tissue. In this work absolute water and fat mass density measurement with in vivo Magnetic Resonance Imaging (MRI) is demonstrated. T1 independent, T2* corrected chemical shift based water-fat separated images are acquired. By placing a phantom with known mass density in the field of view for signal intensity calibration, absolute water or fat mass density can be computed, assuming the B1+ (transmit) and B1- (receive) fields can be measured. Phantom experiments with known ...
Logistic Curves, Extraction Costs And Peak Oil, 2012 University of Dayton
Logistic Curves, Extraction Costs And Peak Oil, Robert J. Brecha
Physics Faculty Publications
Debates about the possibility of a near-term maximum in world oil production have become increasingly prominent over the past decade, with the focus often being on the quantification of geologically available and technologically recoverable amounts of oil in the ground. Economically, the important parameter is not a physical limit to resources in the ground, but whether market price signals and costs of extraction will indicate the efficiency of extracting conventional or nonconventional resources as opposed to making substitutions over time for other fuels and technologies. We present a hybrid approach to the peak-oil question with two models in which the ...
Validation Of Weak Form Thermal Analysis Algorithms Supporting Thermal Signature Generation, 2012 University of Tennessee - Knoxville
Validation Of Weak Form Thermal Analysis Algorithms Supporting Thermal Signature Generation, Elton Lewis Freeman
Extremization of a weak form for the continuum energy conservation principle differential equation naturally implements fluid convection and radiation as flux Robin boundary conditions associated with unsteady heat transfer. Combining a spatial semi-discretization via finite element trial space basis functions with time-accurate integration generates a totally node-based algebraic statement for computing. Closure for gray body radiation is a newly derived node-based radiosity formulation generating piecewise discontinuous solutions, while that for natural-forced-mixed convection heat transfer is extracted from the literature. Algorithm performance, mathematically predicted by asymptotic convergence theory, is subsequently validated with data obtained in 24 hour diurnal field experiments for ...
Reply To “Comment On ‘Accurate And Fast Numerical Solution Of Poisson's Equation For Arbitrary, Space-Filling Voronoi Polyhedra: Near-Field Corrections Revisited’ ”, Aftab Alam, Brian G. Wilson, Duane D. Johnson
Ames Laboratory Publications
This is a Reply to the Comment by Gonis and Zhang on our recent paper. They discuss supposed issues with our “accurate and fast numerical solution of Poisson’s equation for arbitrary Voronoi polyhedra” (VP).
Review Of Treatment Of Error In Second Language Student Writing By Dana R. Ferris, 2012 University of Central Florida
Review Of Treatment Of Error In Second Language Student Writing By Dana R. Ferris, Melanie C. González
Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, 2012 The University of Western Ontario
Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, Hamidreza Azimian
Electronic Thesis and Dissertation Repository
In this thesis, a computational framework for patient-specific preoperative planning of Robotics-Assisted Minimally Invasive Cardiac Surgery (RAMICS) is developed. It is expected that preoperative planning of RAMICS will improve the rate of success by considering robot kinematics, patient-specific thoracic anatomy, and procedure-specific intraoperative conditions. Given the significant anatomical features localized in the preoperative computed tomography images of a patient's thorax, port locations and robot orientations (with respect to the patient's body coordinate frame) are determined to optimize characteristics such as dexterity, reachability, tool approach angles and maneuverability. In this thesis, two approaches for preoperative planning of RAMICS are ...
High Frequency Study Of Magnetic Nanostructures, 2012 University of New Orleans
High Frequency Study Of Magnetic Nanostructures, Abhishek Srivastava
University of New Orleans Theses and Dissertations
The work in this thesis is divided in three parts. In part one we developed electrodeposition method of Nickel Nanowire in commercial AAO template in constant current (Galvanostatic) mode, further we tried to estimate the growth rate from theory, from saturation magnetization and direct measurement from SEM image.
In part two we focused on using the Vector Network Analyzer (VNA) to measure the Ferromagnetic Resonance (FMR))of various magnetic Nanowire arrays. We employed different measurement geometries using microstripline and coplanar waveguide as microwave transmission lines.
In part three our aim was to study the magnetic properties of complex ferromagnetic system ...
Morphology-Properties Studies In Laser Synthesized Nanostructured Materials, 2012 University of Tennessee, Knoxville
Morphology-Properties Studies In Laser Synthesized Nanostructured Materials, Nozomi Shirato
Synthesis of well-defined nanostructures by pulsed laser melting is an interesting subject from both a funda- mental and technological point of view. In this thesis, the synthesis and functional properties of potentially useful materials were studied, such as tin dioxide nanostructured arrays, which have potential applications in hydrogen gas sensing, and ferromagnetic Co nanowire and nanomagnets, which are fundamentally im- portant towards understanding magnetism in the nanoscale. First, the formation of 1D periodic tin dioxide nanoarrays was investigated with the goal of forming nanowires for hydrogen sensing. Experimental obser- vations combined with theoretical modeling successfully explained the mechanisms of structure ...
Analyzing Wind Turbine Controller Effects On Structure Stress, 2012 California State University - East Bay
Analyzing Wind Turbine Controller Effects On Structure Stress, Leo Groner, Susan Frost
STAR Program Research Presentations
Wind turbines generate electric power from clean renewable sources. They must be robust and reliable. Utility-scale turbines are designed to produce power within a set of wind speed parameters. When winds change, wind turbine blade pitch is used to protect the turbine from over speed damage.
Advanced control algorithms can increase power by extending the performance envelope or they can extend lifetime by reducing stress. A FAST simulation written in MATLAB / Simulink is used to simulate the dynamics of the integrated aerodynamic, mechanical and control subsystems of the turbine. Resonance modes may lead to large amplitude displacements and damage. The ...
Electronics Development For The Cherenkov Telescope Array, 2012 SUNY Cortland
Electronics Development For The Cherenkov Telescope Array, Margaret C. Murphy, Justin Vandenbrouke
STAR Program Research Presentations
Gamma-ray astronomy promises to elucidate the highest-energy particle accelerators in the Universe, and could play a key role in identifying the nature of dark matter. The Cherenkov Telescope Array (CTA), currently in the research and development stage, will study and capture gamma-rays with an order of magnitude grater sensitivity than the instruments already in place. Each telescope in the array will be equipped with dozens of camera modules each containing four TeV Array Readout with GSa/s sampling and Event Trigger (TARGET) chips. TARGET 4 has many internal settings, several of which were tested and analyzed to achieve an optimal ...
Temperature Distribution In An Oscillatory Flow With A Sinusoidal Wall Temperature, 2012 University of Texas at Austin
Temperature Distribution In An Oscillatory Flow With A Sinusoidal Wall Temperature, Eduardo Ramos, Brian Storey, Fernando Sierra, Raul Zuniga, Andriy Avramenko
The temperature field generated by an oscillatory boundary layer flow in the presence of a wall with a sinusoidal temperature distribution is analyzed. A linear perturbation method is used to find closed form analytical solutions for the temperature field when the amplitude of the velocity oscillation is small. The analytical solutions only consider long-time behavior when the temperature fields oscillate with the frequency of the flow. The structure of the equation that governs the temperature correction due to convection is similar to that of diffusive waves with the solution consisting of traveling or standing waves. The temperature distribution is also ...
Nanoalloy Composition-Temperature Phase Diagram For Catalyst Design: Case Study Of Ag-Au, 2012 Ames Laboratory
Nanoalloy Composition-Temperature Phase Diagram For Catalyst Design: Case Study Of Ag-Au, Lin-Lin Wang, Teck L. Tan, Duane D. Johnson
Ames Laboratory Publications
By coupling a cluster expansion with density functional theory (DFT) calculations, we determine the configurational thermodynamics (site preferences and occupations) for alloyed nanoparticles (NPs) as functions of composition (c) and temperature (T), exemplified using a 55-atom Ag-Au truncated cuboctahedron NP. The c−T phase diagram for site occupations gives detailed design information for alloyed NP, especially the thermodynamically stable active sites for catalysis and how they change with stoichiometry and processing temperature. Generally, Ag prefers core and Au prefers shell, agreeing with our universal core-shell preference assessed from DFT impurity segregation energies but with interesting multishell configurations having specific active ...
Switch Yard Operation In Thermal Power Plant(Katpp Jhalawar Rajasthan), 2012 Rajasthan Technical University Kota
Switch Yard Operation In Thermal Power Plant(Katpp Jhalawar Rajasthan), Radhey Shyam Meena Er.
Radhey Shyam Meena
Switchyard Provides the facilities for switching ,protection & Control of electric power. To handle high Voltage power with proper Safety measures. To isolate the noises coming from the grid with true 50Hz power SWITCH YARD IS IMPORTANT PART IN THERMAL PLANT. IN KALISINDH THERMAL 400KV AND 220KV SWITCH YARD LOCATED.
Propagation Of Ultrasound Through Freshly Excised Human Calvarium, 2012 University of Nebraska – Lincoln
Propagation Of Ultrasound Through Freshly Excised Human Calvarium, Armando Garcia Noguera
Engineering Mechanics Dissertations & Theses
The propagation of ultrasound through complex biological media, such as the human calvarium, poses a great challenge for modern medicine. Several ultrasonic techniques commonly used for treatment and diagnosis in most of the human body are still difficult to apply to the human brain, in part, because of the properties of the skull. Moreover, an understanding of the biomechanics of transcranial ultrasound may provide needed insight into the problem of blast wave induced traumatic brain injury (TBI). In the present study, the spatial variability of ultrasonic properties was evaluated for relevant frequencies of 0.5, 1, and 2.25 MHz ...
Study Of Jet Transverse Momentum And Jet Rapidity Dependence Of Dijet Azimuthal Decorrelations With The Dø Detector, 2012 Louisiana Tech University
Study Of Jet Transverse Momentum And Jet Rapidity Dependence Of Dijet Azimuthal Decorrelations With The Dø Detector, Kiran Chakravarthula
In a collision experiment involving highly energetic particles such as hadrons, processes at high momentum transfers can provide information useful for many studies involving Quantum Chromodynamics (QCD). One way of analyzing these interactions is through angular distributions. In hadron-hadron collisions, the angular distribution between the two leading jets with the largest transverse momentum (pT) is affected by the production of additional jets. While soft radiation causes small differences in the azimuthal angular distribution of the two leading jets produced in a collision event, additional hard jets produced in the event have more pronounced influence on the distribution of the two ...
The Double Pendulum: Construction And Exploration, 2012 California Polytechnic State University - San Luis Obispo
The Double Pendulum: Construction And Exploration, Benjamin J. Knudson
The exploration of a nonlinear mechanical system, the Double Pendulum, a physical pendulum on the end of a physical pendulum, using analytic and experimental approaches. Also included discussion of the design and construction of the Double Pendulum apparatus to work with Vernier LabPro and LoggerPro. The apparatus outputs live data of the angles to a LoggerPro which collects and produces time evolution graphs as well as a corresponding animation lending itself to comparison with theoretical models. Normal mode frequencies are found both analytically and experimentally for the the general (real) double pendulum. Examples of both simple (periodic) and complex (chaotic ...
Charge-Magnetic Interference Resonant Scattering Studies Of Ferromagnetic Crystals And Thin Films, 2012 Argonne National Laboratory
Charge-Magnetic Interference Resonant Scattering Studies Of Ferromagnetic Crystals And Thin Films, D. Haskel, E. Kravtsov, Y. Choi, J. C. Lang, Z. Islam, G. Srajer, J. S. Jiang, S. D. Bader, Paul C. Canfield
Physics and Astronomy Publications
The element- and site-specificity of X-ray resonant magnetic scattering (XRMS) makes it an ideal tool for furthering our understanding of complex magnetic systems. In the hard X-rays, XRMS is readily applied to most antiferromagnets where the relatively weak resonant magnetic scattering (10−2–10−6 I c ) is separated in reciprocal space from the stronger, Bragg charge scattered intensity, I c . In ferro(ferri)magnetic materials, however, such separation does not occur and measurements of resonant magnetic scattering in the presence of strong charge scattering are quite challenging. We discuss the use of charge-magnetic interference resonant scattering for studies of ...