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Articles 571 - 600 of 648
Full-Text Articles in Mechanical Engineering
Low Reynolds Number Water Flow Characteristics Through Rectangular Micro Diffusers/Nozzles With A Primary Focus On Major/Minor P, Kyle Hallenbeck
Low Reynolds Number Water Flow Characteristics Through Rectangular Micro Diffusers/Nozzles With A Primary Focus On Major/Minor P, Kyle Hallenbeck
Electronic Theses and Dissertations
The field of microfluidics has recently been gathering a lot of attention due to the enormous demand for devices that work in the micro scale. The problem facing many researchers and designers is the uncertainty in using macro scaled theory, as it seems in some situations they are incorrect. The general idea of this work was to decide whether or not the flow through micro diffusers and nozzles follow the same trends seen in macro scale theory. Four testing wafers were fabricated using PDMS soft lithography including 38 diffuser/nozzle channels a piece. Each nozzle and diffuser consisted of a throat …
Design And Fabrication Of Chemiresistor Typemicro/Nano Hydrogen Gas Sensors Usinginterdigitated Electrodes, Peng Zhang
Design And Fabrication Of Chemiresistor Typemicro/Nano Hydrogen Gas Sensors Usinginterdigitated Electrodes, Peng Zhang
Electronic Theses and Dissertations
Hydrogen sensors have obtained increased interest with the widened application of hydrogen energy in recent years. Among them, various chemiresistor based hydrogen sensors have been studied due to their relatively simple structure and well-established detection mechanism. The recent progress in micro/nanotechnology has accelerated the development of small-scale chemical sensors. In this work, MEMS (Micro-Electro-Mechanical Systems) sensor platforms with interdigitated electrodes have been designed and fabricated. Integrating indium doped tin dioxide nanoparticles, these hydrogen sensors showed improved sensor characteristics such as sensitivity, response and selectivity at room temperature. Design parameters of interdigitated electrodes have been studied in association with sensor characteristics. …
Methane And Dimethyl Ether Oxidation At Elevated Temperatures And Pressure, Christopher Zinner
Methane And Dimethyl Ether Oxidation At Elevated Temperatures And Pressure, Christopher Zinner
Electronic Theses and Dissertations
Autoignition and oxidation of two Methane (CH4) and Dimethyl Ether (CH3OCH3 or DME) mixtures in air were studied in shock tubes over a wide range of equivalence ratios at elevated temperatures and pressures. These experiments were conducted in the reflected shock region with pressures ranging from 0.8 to 35.7 atmospheres, temperatures ranging from 913 to 1650 K, and equivalence ratios of 2.0, 1.0, 0.5, and 0.3. Ignition delay times were obtained from shock-tube endwall pressure traces for fuel mixtures of CH4/CH3OCH3 in ratios of 80/20 percent volume and 60/40 percent volume, respectively. Close examination of the data revealed that energy …
Water Footprint Of Aviation Fuel Synthesis By The Fischer Tropsch Process Using Sugar Cane Waste & Landfill Gas As Feedstocks, Slim Menzli
Electronic Theses and Dissertations
The recent spikes in oil prices have spurred an already bullish demand on biofuels as a source of alternative energy. However, the unprecedented price records set simultaneously by staple food have raised high concerns about potential impacts of biofuels on the global agricultural landscape as fuel and food markets are being inextricably coupled. The revival of interest in the Fischer-Tropsch (FT) process comes into full force since it offers a promising way to produce carbon-neutral liquid fuels which are readily usable with today's existing infrastructure. The FT synthesis offers the possibility of using crop waste as feedstock instead of the …
Fundamental Study Of Fc-72 Pool Boiling Surface Temperature Fluctuations And Bubble Behavior, Alison Griffin
Fundamental Study Of Fc-72 Pool Boiling Surface Temperature Fluctuations And Bubble Behavior, Alison Griffin
Electronic Theses and Dissertations
A heater designed to monitor surface temperature fluctuations during pool boiling experiments while the bubbles were simultaneously being observed has been fabricated and tested. The heat source was a transparent indium tin oxide (ITO) layer commercially deposited on a fused quartz substrate. Four copper-nickel thin film thermocouples (TFTCs) on the heater surface measured the surface temperature, while a thin layer of sapphire or fused silica provided electrical insulation between the TFTCs and the ITO. The TFTCs were micro-fabricated using the liftoff process to deposit the nickel and copper metal films. The TFTC elements were 50 microns wide and overlapped to …
A Customer Programmable Microfluidic System, Miao Liu
A Customer Programmable Microfluidic System, Miao Liu
Electronic Theses and Dissertations
Microfluidics is both a science and a technology offering great and perhaps even revolutionary capabilities to impact the society in the future. However, due to the scaling effects there are unknown phenomena and technology barriers about fluidics in microchannel, material properties in microscale and interactions with fluids are still missing. A systematic investigation has been performed aiming to develop "A Customer Programmable Microfluidic System". This innovative Polydimethylsiloxane (PDMS)-based microfluidic system provides a bio-compatible platform for bio-analysis systems such as Lab-on-a-chip, micro-total-analysis system and biosensors as well as the applications such as micromirrors. The system consists of an array of microfluidic …
Effect Of Pressure Gradient And Wake On Endwall Film Cooling Effectiveness, Sylvette Rodriguez
Effect Of Pressure Gradient And Wake On Endwall Film Cooling Effectiveness, Sylvette Rodriguez
Electronic Theses and Dissertations
Endwall film cooling is a necessity in modern gas turbines for safe and reliable operation. Performance of endwall film cooling is strongly influenced by the hot gas flow field, among other factors. For example, aerodynamic design determines secondary flow vortices such as passage vortices and corner vortices in the endwall region. Moreover blockage presented by the leading edge of the airfoil subjects the incoming flow to a stagnating pressure gradient leading to roll-up of the approaching boundary layer and horseshoe vortices. In addition, for a number of heavy frame power generation gas turbines that use cannular combustors, the hot and …
Design And Experimental Study Of An Integrated Vapor Chamber -" Thermal Energy Storage System, Krishna Kota
Design And Experimental Study Of An Integrated Vapor Chamber -" Thermal Energy Storage System, Krishna Kota
Electronic Theses and Dissertations
Future defense, aerospace and automotive technologies involve electronic systems that release high pulsed waste heat like during high power microwave and laser diode applications in tactical and combat aircraft, and electrical and electronic systems in hybrid electric vehicles, which will require the development of an efficient thermal management system. A key design issue is the need for fast charging so as not to overheat the key components. The goal of this work is to study the fabrication and technology implementation feasibility of a novel high energy storage, high heat flux passive heat sink. Key focus is to verify by theory …
Thermal Modeling And Laser Beam Shaping For Microvias Drilling In High Density Packaging, Chong Zhang
Thermal Modeling And Laser Beam Shaping For Microvias Drilling In High Density Packaging, Chong Zhang
Electronic Theses and Dissertations
Laser drilling of microvias for organic packaging applications is studied in present research. Thermal model is essential to understand the laser-materials interactions and to control laser drilling of blind micro holes through polymeric dielectrics in multilayer electronic substrates. In order to understand the profile of the drilling front irradiated with different laser beam profiles, a transient heat conduction model including vaporization parameters is constructed. The absorption length in the dielectric is also considered in this model. Therefore, the volumetric heating source criteria are applied in the model and the equations are solved analytically. The microvia drilling speed, temperature distribution in …
Meshless Hemodynamics Modeling And Evolutionary Shape Optimization Of Bypass Grafts Anastomoses, Zaher El Zahab
Meshless Hemodynamics Modeling And Evolutionary Shape Optimization Of Bypass Grafts Anastomoses, Zaher El Zahab
Electronic Theses and Dissertations
Objectives: The main objective of the current dissertation is to establish a formal shape optimization procedure for a given bypass grafts end-to-side distal anastomosis (ETSDA). The motivation behind this dissertation is that most of the previous ETSDA shape optimization research activities cited in the literature relied on direct optimization approaches that do not guaranty accurate optimization results. Three different ETSDA models are considered herein: The conventional, the Miller cuff, and the hood models. Materials and Methods: The ETSDA shape optimization is driven by three computational objects: a localized collocation meshless method (LCMM) solver, an automated geometry pre-processor, and a genetic-algorithm-based …
An Improved Thermoregulatory Model For Cooling Garment Applications With Transient Metabolic Rates, Johan Westin
An Improved Thermoregulatory Model For Cooling Garment Applications With Transient Metabolic Rates, Johan Westin
Electronic Theses and Dissertations
Current state-of-the-art thermoregulatory models do not predict body temperatures with the accuracies that are required for the development of automatic cooling control in liquid cooling garment (LCG) systems. Automatic cooling control would be beneficial in a variety of space, aviation, military, and industrial environments for optimizing cooling efficiency, for making LCGs as portable and practical as possible, for alleviating the individual from manual cooling control, and for improving thermal comfort and cognitive performance. In this study, we adopt the Fiala thermoregulatory model, which has previously demonstrated state-of-the-art predictive abilities in air environments, for use in LCG environments. We validate the …
Pressure Losses Experienced By Liquid Flow Through Pdms Microchannels With Abrupt Area Changes, Jonathan Wehking
Pressure Losses Experienced By Liquid Flow Through Pdms Microchannels With Abrupt Area Changes, Jonathan Wehking
Electronic Theses and Dissertations
Given the surmounting disagreement amongst researchers in the area of liquid flow behavior at the microscale for the past thirty years, this work presents a fundamental approach to analyzing the pressure losses experienced by the laminar flow of water (Re = 7 to Re = 130) through both rectangular straight duct microchannels (of widths ranging from 50 to 130 micrometers), and microchannels with sudden expansions and contractions (with area ratios ranging from 0.4 to 1.0) all with a constant depth of 104 micrometers. The simplified Bernoulli equations for uniform, steady, incompressible, internal duct flow were used to compare flow through …
User-Defined Patterning Of Neural Progenitor Cells On 3d Micropillar Arrays Using Round Cross-Sectional Geometry, Specific Dimen, Andrea Wesser
User-Defined Patterning Of Neural Progenitor Cells On 3d Micropillar Arrays Using Round Cross-Sectional Geometry, Specific Dimen, Andrea Wesser
Electronic Theses and Dissertations
The ability to control stem cell functions, particularly neuronal progenitors, has long since been believed to be the key to successful treatment of neurodegenerative disorders such as Alzheimer's, Parkinson's and accidents involving head trauma. The neurology field calls for many new solutions to address the controlled neural stem cell seeding and placement of cells for neural tissue regeneration. Self-assembled monolayers (SAM) from the alkanethiol group provide a straightforward applicable, reliable treatment for cell adhesion. An ODT/gold treatment was used to adhere the cells to patterned areas, due mainly to a high confluence of cells attracted to it, as well as …
Design Of An Active Orthotic Device For Joint Management., Steven Clayton Anderson
Design Of An Active Orthotic Device For Joint Management., Steven Clayton Anderson
Electronic Theses and Dissertations
Existing treatment programs and procedures are incapable of addressing the complications encountered with patients who experience spasticity and hypertonia related joint contractures. Current passive therapy procedures and devices are only capable of managing the extent of joint contractures on patients with chronic and acute onset severe neurological disorders. The project was conceived as a means to develop an active device that is capable of adapting to the state of the joint to mange the extent of contractures and to permit consideration for the prevalence of spastic activity episodes and hypertonia. The project focused on the design of the physical prototype …
Effects Of Position, Orientation, And Infiltrating Material On Three Dimensional Printing Models, Joseph William Frascati
Effects Of Position, Orientation, And Infiltrating Material On Three Dimensional Printing Models, Joseph William Frascati
Electronic Theses and Dissertations
This research defined and evaluated mechanical properties of prototypes created using a plaster based three-dimensional printing (3DP) system commercialized by Z Corporation. 3DP is one of the fastest growing forms of rapid prototyping. Till date, there is little or no information available on material properties of infiltrants used in 3DP. This research work evaluated and documented some of the useful information for 3DP users by determining the effect of build position, build orientation and infiltration materials on the strength of prototypes. The study was performed in three different phases to limit the processing variables and to arrive at definite conclusions …
High Pressure Testing Of Composite Solid Rocket Propellant Mixtures: Burner Facility Characterization, Rodolphe Valentin Carro
High Pressure Testing Of Composite Solid Rocket Propellant Mixtures: Burner Facility Characterization, Rodolphe Valentin Carro
Electronic Theses and Dissertations
Much Research on composite solid propellants has been performed over the past few decades and much progress has been made, yet many of the fundamental processes are still unknown, and the development of new propellants remains highly empirical. Ways to enhance the performance of solid propellants for rocket and other applications continue to be explored experimentally, including the effects of various additives and the impact of fuel and oxidizer particle sizes on burning behavior. One established method to measure the burning rate of composite propellant mixtures in a controlled laboratory setting is to use a constant-volume pressure vessel, or strand …
Liquid Crystal Thermography Studies In Water Pool Boiling At Subatmospheric Pressures, Kiran Talari
Liquid Crystal Thermography Studies In Water Pool Boiling At Subatmospheric Pressures, Kiran Talari
Electronic Theses and Dissertations
A pool boiling experimental facility has been designed and built to investigate nucleate pool boiling in water under sub atmospheric pressure. Liquid crystal thermography, a non intrusive technique, is used for the determination of surface temperature distributions. This technique uses encapsulated liquid crystals that reflect definite colors at specific temperatures and viewing angle. Design of the test section is important in this experimental study. Since a new TLC is required for every new set of test conditions, a permanently sealed test section is not an option. The real challenge is to design a leak proof test section which is flexible …
Wall Heat Transfer Effects In The Endwall Region Behind A Reflected Shock Wave At Long Test Times, Corey Frazier
Wall Heat Transfer Effects In The Endwall Region Behind A Reflected Shock Wave At Long Test Times, Corey Frazier
Electronic Theses and Dissertations
Shock-tube experiments are typically performed at high temperatures (≥1200K) due to test-time constraints. These test times are usually ~1 ms in duration and the source of this short, test-time constraint is loss of temperature due to heat transfer. At short test times, there is very little appreciable heat transfer between the hot gas and the cold walls of the shock tube and a high test temperature can be maintained. However, some experiments are using lower temperatures (approx. 800K) to achieve ignition and require much longer test times (up to 15 ms) to fully study the chemical kinetics and combustion chemistry …
Heat Transfer In Multi-Layer Energetic Nanofilm On Composites Substrate, Manesh Navid Amini
Heat Transfer In Multi-Layer Energetic Nanofilm On Composites Substrate, Manesh Navid Amini
Electronic Theses and Dissertations
The main purpose of this work is the physical understanding and the numerical description of the reaction of the dense metastable intermolecular composition (MIC). Energy density of MIC is much higher than conventional energetic material; therefore, MIC finds more applications in the propellant and explosive system. The physical model includes the speed of propagation and rate of reaction, and the relationship between the layer thickness, heat rate, and length of the flame based on physical model. In Part I of this thesis, a one-dimensional model based on Weihs was developed for 20 pairs of a multi-layer of aluminum and copper …
A Study Of Syngas Oxidation At High Pressures And Low Temperatures, Danielle Marie Kalitan
A Study Of Syngas Oxidation At High Pressures And Low Temperatures, Danielle Marie Kalitan
Electronic Theses and Dissertations
Ignition and oxidation characteristics of CO/H2, H2/O2 and CO/H2/CH4/CO2/Ar fuel blends in air were studied using both experimental and computer simulation methods. Shock-tube experiments were conducted behind reflected shock waves at intermediate temperatures (825 < T < 1400 K) for a wide range of pressures (1 < P < 45 atm). Results of this study provide the first undiluted fuel-air ignition delay time experiments to cover such a wide range of syngas mixture compositions over the stated temperature range. Emission in the form of chemiluminescence from the hydroxyl radical (OH*) transition near 307 nm and the pressure behind the reflected shock wave were used to monitor reaction progress from which ignition delay times were determined. In addition to the experimental analysis, chemical kinetics calculations were completed to compare several chemical kinetics mechanisms to the new experimental results. Overall, the models were in good agreement with the shock-tube data, especially at higher temperatures and lower pressures, yet there were some differences between the models at higher pressures and the lowest temperatures, in some cases by as much as a factor of five. In order to discern additional information from the chemical kinetics mechanisms regarding their response to a wide range of experimental conditions, ignition delay time and reaction rate sensitivity analyses were completed at higher and lower temperatures and higher and lower pressures. These two sensitivity analyses allow for the identification of the key reactions responsible for ignition. The results of the sensitivity analysis indicate that the ignition-enhancing reaction H + O2 = O + OH and hydrogen oxidation kinetics in general were most important regardless of mixture composition, temperature or pressure. However, lower-temperature, higher-pressure ignition delay time results indicate additional influence from HO2- and CO- containing reactions, particularly the well-known H + O + M = HO2 + M reaction and also the CO + O + M = CO2 + M and CO + HO2 = CO2 + OH reactions. Differences in the rates of the CO-related reactions are shown to be the cause of some of the discrepancies amongst the various models at elevated pressures. However, the deviation between the models and the experimental data at the lowest temperatures could not be entirely explained by discrepancies in the current rates of the reactions contained within the mechanisms. Additional calculations were therefore performed to gain further understanding regarding the opposing ignition behavior for calculated and measured ignition delay time results. Impurities, friction induced ionization, static charge accumulation, boundary layer effects, wall reaction effects, and revised chemical kinetics were all considered to be possible mechanisms for the model and measured data disparity. For the case of wall-reaction effects, additional shock-tube experiments were conducted. For the remaining effects listed above, only detailed calculations were conducted. Results from this preliminary anomaly study are at this time inconclusive, but likely avenues for future study were identified. Additional kinetics calculations showed that the large difference between the experimental data and the chemical kinetics models predictions at low temperatures can be explained by at least one missing reaction relevant to low-temperature and high-pressure experimental conditions involving the formation of H2O2, although further study beyond the scope of this thesis is required to prove this hypothesis both theoretically and experimentally.
An Interactive Framework For Meshless Methods Analysis In Computational Mechanics And Thermofluids, Salvadore Anthony Gerace
An Interactive Framework For Meshless Methods Analysis In Computational Mechanics And Thermofluids, Salvadore Anthony Gerace
Electronic Theses and Dissertations
In recent history, the area of physics-based engineering simulation has seen rapid increases in both computer workstation performance as well as common model complexity, both driven largely in part by advances in memory density and availability of clusters and multi-core processors. While the increase in computation time due to model complexity has been largely offset by the increased performance of modern workstations, the increase in model setup time due to model complexity has continued to rise. As such, the major time requirement for solving an engineering model has transitioned from computation time to problem setup time. This is due to …
Lattice Boltzmann Simulation To Study Single And Multi Bubble Dynamics, Amit Gupta
Lattice Boltzmann Simulation To Study Single And Multi Bubble Dynamics, Amit Gupta
Electronic Theses and Dissertations
In recent years, the lattice Boltzmann method (LBM) has emerged as a powerful tool that has replaced conventional macroscopic techniques like Computational Fluid Dynamics (CFD) in many applications. The LBM starts from meso- and microscopic Boltzmann's kinetic equation to determine macroscopic fluid dynamics. The origins of LBM can be drawn back to lattice gas cellular automata (LGCA); however it lacks Galilean invariance and creates statistical noise in the system. LBM on the other hand does away from these drawbacks of LGCA, and is easy to implement in complex geometries and can be used to study microscopic flow behavior in complex …
The Nature Of Turbulence In A Narrow Apex Angle Isosceles Triangular Duct, Vaidyanathan Krishnan
The Nature Of Turbulence In A Narrow Apex Angle Isosceles Triangular Duct, Vaidyanathan Krishnan
Electronic Theses and Dissertations
An experimental investigation was performed to ascertain the nature of turbulence in a narrow apex angle isosceles triangular duct. The study involved the design and construction of a low noise, low turbulence wind tunnel that had an isosceles triangular test section with an apex angle of 11.5[degrees]. Experiments involved the measurement of velocity fluctuations using hot wire anemometry and wall pressure fluctuations using a condenser microphone. Measurement of the velocity fluctuations reconfirms the coexistence of laminar and turbulent regions at a given cross section for a range of Reynolds numbers. The laminar region is concentrated closer to the apex while …
Methods Of Extrapolating Low Cycle Fatigue Data To High Stress Amplitudes, David Charles Radonovich
Methods Of Extrapolating Low Cycle Fatigue Data To High Stress Amplitudes, David Charles Radonovich
Electronic Theses and Dissertations
Modern gas turbine component design applies much effort into prediction and avoidance of fatigue. Advances in the prediction of low-cycle fatigue (LCF) cracks will reduce repair and replacement costs of turbine components. These cracks have the potential to cause component failure. Regression modeling of low-cycle fatigue (LCF)test data is typically restricted for use over the range of the test data. It is often difficult to characterize the plastic strain curve fit constants when the plastic strain is a small fraction of the total strain acquired. This is often the case with high strength, moderate ductility Ni-base superalloys. The intent of …
Annular Beam Shaping And Optical Trepanning, Danyong Zeng
Annular Beam Shaping And Optical Trepanning, Danyong Zeng
Electronic Theses and Dissertations
Percussion drilling and trepanning are two laser drilling methods. Percussion drilling is accomplished by focusing the laser beam to approximately the required diameter of the hole, exposing the material to one or a series of laser pulses at the same spot to melt and vaporize the material. Drilling by trepanning involves cutting a hole by rotating a laser beam with an optical element or an xy galvo-scanner. Optical trepanning is a new laser drilling method using an annular beam. The annular beams allow numerous irradiance profiles to supply laser energy to the workpiece and thus provide more flexibility in affecting …
Study Of Discharge Coefficient And Trends In Film Cooling Effectiveness Of Conical Holes With Increasing Diffusion Angles, Humberto Zuniga,
Study Of Discharge Coefficient And Trends In Film Cooling Effectiveness Of Conical Holes With Increasing Diffusion Angles, Humberto Zuniga,
Electronic Theses and Dissertations
Previous studies indicate that increasing the diffusion angle in conical film-cooling holes leads to an improvement in their film cooling effectiveness. Discharge coefficient and film cooling effectiveness measurements are conducted to characterize this behavior. Part of the focus of this investigation is to find out how this trend develops and attempt to ascertain the optimum cone angle, if possible. Six test plates, each with one row of eight conical-shaped cooling holes of equal diffusion angles of 0, 1, 2, 3, 6, or 8 [degrees], with respect to the hole axis are used in this study. The ratios of the hole …
Efficient Large Scale Transient Heat Conduction Analysis Using A Parallelized Boundary Element Method, Kevin Erhart
Efficient Large Scale Transient Heat Conduction Analysis Using A Parallelized Boundary Element Method, Kevin Erhart
Electronic Theses and Dissertations
A parallel domain decomposition Laplace transform Boundary Element Method, BEM, algorithm for the solution of large-scale transient heat conduction problems will be developed. This is accomplished by building on previous work by the author and including several new additions (most note-worthy is the extension to 3-D) aimed at extending the scope and improving the efficiency of this technique for large-scale problems. A Laplace transform method is utilized to avoid time marching and a Proper Orthogonal Decomposition, POD, interpolation scheme is used to improve the efficiency of the numerical Laplace inversion process. A detailed analysis of the Stehfest Transform (numerical Laplace …
Novel Conceptual Design And Anlysis Of Polymer Derived Ceramic Mems Sensors For Gas Turbine Environment, Narasimha Nagaiah
Novel Conceptual Design And Anlysis Of Polymer Derived Ceramic Mems Sensors For Gas Turbine Environment, Narasimha Nagaiah
Electronic Theses and Dissertations
Technical challenges for developing micro sensors for Ultra High Temperature and turbine applications lie in that the sensors have to survive extremely harsh working conditions that exist when converting fuel to energy. These conditions include high temperatures (500-1500°C), elevated pressures (200-400 psi), pressure oscillations, corrosive environments (oxidizing conditions, gaseous alkali, and water vapors), surface coating or fouling, and high particulate loading. Several technologies are currently underdeveloped for measuring these parameters in turbine engines. One of them is an optical-based non-contact technology. However, these nondirective measuring technologies lack the necessary accuracy, at least at present state. An alternative way to measure …
Design And Implementation Of An Emission Spectroscopy Diagnostic In A High-Pressure Strand Burner For The Study Of Solid Propell, Jason Arvanetes
Design And Implementation Of An Emission Spectroscopy Diagnostic In A High-Pressure Strand Burner For The Study Of Solid Propell, Jason Arvanetes
Electronic Theses and Dissertations
The application of emission spectroscopy to monitor combustion products of solid rocket propellant combustion can potentially yield valuable data about reactions occurring within the volatile environment of a strand burner. This information can be applied in the solid rocket propellant industry. The current study details the implementation of a compact spectrometer and fiber optic cable to investigate the visible emission generated from three variations of solid propellants. The grating was blazed for a wavelength range from 200 to 800 nm, and the spectrometer system provides time resolutions on the order of 1 millisecond. One propellant formula contained a fine aluminum …
Automated Adaptive Data Center Generation For Meshless Methods, Eric Mitteff
Automated Adaptive Data Center Generation For Meshless Methods, Eric Mitteff
Electronic Theses and Dissertations
Meshless methods have recently received much attention but are yet to reach their full potential as the required problem setup (i.e. collocation point distribution) is still significant and far from automated. The distribution of points still closely resembles the nodes of finite volume-type meshes and the free parameter, c, of the radial-basis expansion functions (RBF) still must be tailored specifically to a problem. The localized meshless collocation method investigated requires a local influence region, or topology, used as the expansion medium to produce the required field derivatives. Tests have shown a regular cartesian point distribution produces optimal results, however, in …