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Statistical Continuum Theory For Inelastic Behavior Of A Two-Phase Medium, Brent L. Adams, H. Garmestani, S. Lin

Faculty Publications

This work was supported in part (B.L. Adams) by the MRSEC Program of the National Science Foundation under Award no. DMR-9632556. Further support was provided by the Center for Materials Research and Technology (MARTECH at FSU) and Center for Nonlinear and Nonequilibrium Sciences (CENNAS at FAMU). A statistical contiuum mechanics formulation is presented to predict the inelastic behavior of a medium consisting of two isotropic phases. The phase distribution and morphology are represented by a two-point probability function. The isotropic behavior of the single phase medium is represented by a power law relationship between the strain rate and the resolved …

A Portable Photovoltaic Water Aeration System, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Water aeration is a method to improve the water quality in a lake by adding oxygen to the water. Because water aeration systems are often located in remote locations, photovoltaics are ideal for powering these systems. This paper describes a water aeration system powered by photovoltaics that is used in Florida. The portable nature of this system permits the owner to conveniently relocate the system and aerate bodies of water as needed.

Development And Experimental Verification Of A Three-Dimensional Model Of Left Ventricular Flow Dynamics, Tong Ding

FIU Electronic Theses and Dissertations

Ischemic heart disease, which results from the insufficient coronary artery blood flow is a leading cause of mortality in developed countries. It manifests itself by abnormal left ventricular wall motion during systole.

A three dimensional numerical model was developed to simulate the flow patterns in the left ventricle. Numerical solutions were obtained by discretizing the Navier-Stokes equations for viscous, incompressible, steady flow using finite element method.

A diagnostic index Central Ejection Region (CER) as well as its quantitative version CER coefficient which are based on the flow patterns were defined as the region in which velocity vectors were aligned 5 …

Measured Energy Savings Of A Comprehensive Retrofit In An Existing Florida Residence, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Simulation analysis suggests that electricity consumption can be reduced up to 40% in existing Florida homes with judicious use of methods to reduce loads, as well as more efficient equipment. To test this theory, an all-electric home was located in Miami, Florida upon which to perform a variety of retrofits. The total annual electricity consumption in the one year base-line period preceding the study was 20,733 kWh. Although high, this is not unusual for a South Florida home with a swimming pool since pool pumping often accounts 3,000 -4,000 kWh per year. Detailed instrumentation and metering equipment was installed in …

Microelectromechanical Optical Beam Steering Systems, David M. Burns

Theses and Dissertations

The development of microelectromechanical systems (MEMS) has matured to the point where the fabrication of micron sized devices is feasible. State of the art MEMS construction processes now support the fabrication of novel optical devices that could not previously be built. This dissertation reports on the development of innovative micro optical devices such as Variable Blaze Gratings (VBGs) using state of the art MEMS construction processes. The principle application of the micro optical devices described in this dissertation is steering optical beams; however other applications such as spectral analysis are identified. Specific optical beam steering systems developed and characterized in …

Microelectromechanical Scanner Using A Vertical Cavity Surface Emitting Laser, Joseph G. Bouchard Jr.

Theses and Dissertations

Optical scanners play a prominent role in the commercial and military industries. The scanner's size, cost and reliability are critical characteristics. In this research a microoptical scanning system was fabricated by incorporating a vertical cavity surface emitting laser (VCSEL) onto a surface machined microelectromechanical die. The micro optics for laser beam steering includes a 135 deg mirror, a Fresnel lens, a lateral scanning rotating mirror, and a vertical scanning fan mirror. The VCSEL was attached to the die by solder and electrical connection was provided by wire bonding. Based on far field measurements the scanner had a lateral scan angle …

Micro-Electromechanical Switches For Micro-Satellite Power Transfer, Glen A. Kading

Theses and Dissertations

In the past few years, microelectromechanical systems (MEMS) have emerged as a promising new technology with tremendous application potential. One of the possible implementations of MEMS technology is in the development of micro-satellites. It should be possible to mass-produce micro-satellites at a fraction of the cost of one conventional satellite. In order for satellites to be robust, a method of transferring power to systems must be addressed. As micro-satellites are made with conventional integrated circuit technologies at a very small scale, a means of transferring power on a similar scale will be investigated. This research addresses the issue of the …

Effects Of Liquid Transpiration Cooling On Heat Transfer To The Diverging Region Of A Porous-Walled Nozzle, Daniel J. Schieb

Theses and Dissertations

This research effort investigated the effects of evaporation of water on the heat transferred to the wall of the diverging portion of a porous walled nozzle The AFIT High Pressure Shock Tube was used with a two-dimensional Mach 3 nozzle. One flat surface of the nozzle was fitted with a layer of porous stainless steel from the nozzle throat to the exit. This porous material was saturated with water to simulate liquid transpiration cooling. Surface temperature data was taken in this region using fast response coaxial thermocouple. Heat transfer was determined from the surface temperature history. Data was taken for …

Experimental Investigation Of Water Spray Cooling Characteristics Of A Solid Heated Surface, Rainer F. Ponzel

Masters Theses

Water spray cooling characteristics of a solid heated surface were investigated to better understand the physical phenomenon of nucleate boiling heat transfer for full cone sprays. An experimental test loop was developed to conduct the spray cooling experiments. A uniform heat flux condition was assumed, and the liquid flow rate and nozzle orifice diameter were selected as the main variables. Two water temperatures were chosen to perform the study. Saturated water spray was utilized to measure the wall superheat temperature. Subcooled water spray was applied to investigate the effect of water spray in the single-phase regime.

Experiments conducted using the …

Investigation And Demonstration Of A Rich Combustor Cold Start Device For Alcohol Fueled Engines, David Kim Irick

Doctoral Dissertations

Alcohols (methanol and ethanol) have been identified as having the potential to improve air quality when used to replace conventional gasoline. This potential is primarily due to the different organic species that are emitted by alcohol-fueled engines. The use of "near neat" alcohols gives greater benefits than fuels containing lower levels of alcohol, but neat alcohols present a significant cold starting problem.

The primary objective of this study was to develop a rich combustor device which will extend the cold start range of alcohol fueled engines to -30°C while reducing cold start emissions. In support of this objective a software …

Energy Needs During Disasters: Workshop Summary Report, Florida Solar Energy Center, Gerard Ventre

FSEC Energy Research Center®

When natural disasters, such as hurricanes, earthquakes and floods, occur, thousands of people can be left without homes, electrical power, communications, potable water, and food storage capabilities. Adequate electrical power is imperative for both disaster relief operations and community rebuilding. However, the disaster may have disrupted the commercial power supply to a community, requiring disaster relief agencies to rely on alternative sources of power. Photovoltaic-powered equipment provides electrical power which is renewable, quiet, and safe, and which can be used for many essentials of disaster relief efforts, such as refrigeration, communications and lighting. However, at present, photovoltaic (PV) technology is …

Tractor Test Museum Commttee Minutes November 19th, 1997, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Update on Roof Progress Big Red Club State Fair Project

Pv Powering A Weather Station For Severe Weather, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

A natural disaster, such as Hurricane Andrew, destroys thousands of homes and businesses. The destruction from this storm left thousands of people without communications, potable water, and electric power. This prompted the Florida Solar Energy Center to study the application of solar electric power for use in disasters.

During this same period, volunteers at the Tropical Prediction Center at the National Hurricane Center (NHC) and the Miami Office of the National Weather Service (NWS) were working to increase the quantity and quality of observations received from home weather stations.

Many weather data collecting stations are at remote sites, which are …

Maine Guide To Energy Efficient Residential Construction : A Manual Of Accepted Practices, State Of Maine Energy Conservation Division

Maine Collection

Maine Guide to Energy Efficient Residential Construction : A Manual of Accepted Practices

State of Maine Energy Conservation Division, Department of Economic and Community Development, 59 State House Station, Augusta, Maine 04333-0059

Second Edition - November, 1997

Contents: Dedication / Acknowledgements / Introduction / Part 1. Summary of Maine's Residential Energy Standards / Part 2. Siting and Initial Design Considerations / Part 3. Important Considerations for the Design Phase / Part 4. Recommended Construction Practices / Appendixes

Robotic Tcf And Rigid-Body Calibration Methods, Edward Red, Xuguang Wang

Faculty Publications

For off-line programming to work, systematic methods must be developed to account for non-ideal performance of the parts and devices in the manufacturing cell. Although much of the literature focuses on robot inaccuracy, this paper considers practical methods for the tool control frame (TCF) calibration and rigid-body compensation required to close the inverse kinematics loop for target driven tasks.

Extracting The Relative Grain Boundary Free Energy And Mobility Functions From The Geometry Of Microstructures, Brent L. Adams, D. Kinderlehrer, W. W. Mullins, Anthony D. Rollett, Shlomo Ta'asan

Faculty Publications

This work was supported primarily by the MRSEC Program of the National Science Foundation under Award Number DMR-9632556. This paper describes a method for extracting, from measurements of a polycrystal, the relative excess free energy and the relative mobility of the grain boundaries as functions of the crystallographic type (five degrees of freedom) and relevant thermodynamic variables. The method requires the simultaneous measurement of both the geometry and the crystallography of a large number of grain boundary intersections; the crystallographic information may be obtained from orientation imaging microscopy (OIM). For simplicity, the intersections will be assumed to be triple junctions …

Nonlinear Optimal Control Of A Hydraulically Actuated Positioning System, Timothy Mclain, Randal W. Beard

Faculty Publications

In this paper, the nonlinear optimal control problem is formulated for the position control of an electrohydraulic servo system. The optimal control is given by the solution to the Hamilton-Jacobi-Bellman equation, which in this case cannot be solved explicitly. An alternative method, based upon successive Galerkin approximation, is used to obtain an approximate optimal solution. Preliminary simulation results, demonstrating the application of this approach to the position control of a hydraulically actuated device, are presented.

Automobile Air Bag Inflation System Based On Fast Combustion Reaction, Yacoob Tabani

Dissertations

Current automobile air bag inflator technology is complex, expensive and environmentally unsafe. A new and novel air bag inflator based on fast combustion reactions of methane-oxygen mixtures has been developed and studied. The thermodynamics and mass flow parameters of this new inflator have been modeled and found to be in agreement with experimental results.

The performance of the fast combustion inflator was evaluated in terms of pressure-time relationships inside the inflator and in a receiving tank simulating an air bag as well as the temperature-time relationship in the tank.

In order to develop this fast combustion inflator, several critical issues …

Electrocatalytic Control Of Exhaust Soot, Victor L. Callahan

Dissertations

The feasibility of combining electrostatic precipitation and use of a catalytic wall in a straight tube reactor as a means of destroying soot particles was investigated. Enhanced particle diffusion to the wall by an applied electric field provided the means of particle capture for subsequent catalytic oxidation at the active surface in a small length tube.

Soot particles flowing in a gas stream are influenced by the following transport mechanisms: convective flux as a result of bulk flow, diffusion flux as a result of particle concentration or number density gradient, and an electrostatic flux from the coulombic attraction as charged …

Modeling Of Deformed Swept Volumes With Sde And Its Applications To Nc Simulation And Verification, Feng Lu

Theses

Representation of swept volumes has important applications in NC simulation and verification as well as robot-motion planning. Most research on .the representation of swept volumes has been limited to rigid objects. In this study, a sweep deferential equation (SDE) approach is presented for the representation of deformed swept volumes generated by flexible objects.

The deformed swept volume analysis is integrated with machining physics to account for tool deformation/deflection for the NC simulation. End milling is modeled and analyzed and the tool deformations are calculated and integrated with the SDE program. A program is developed in C++ for the generation of …

Computational Determination Of Laminar Flow Loss Coefficients In 90° Channel Bend, Leonard Paul Parkin

Theses

Loss coefficients for laminar two dimensional incompressible channel (or duct) flow in a 90° bend are investigated using FEM software, FIDAP. This problem consists of a two dimensional duct with a 90° bend of constant radius flowing with water, at 70°F and atmositeno conditions. The bend radius to duct width ratios examined were 1.5 and 1.0. Both bend radius to duct width ratios were analyzed for Reynolds Number ranging from 50 to 1800. The pressure and velocity distributions were found and used to determine the pressure due to the bend. The results show the pressure loss effect due to the …

Mechanical Design Of An Experimental Parallel Robot, Philip Song

Theses

OSCAR, or Operational Space Controlled Adjustable Robot, is a parallel-actuated manipulator, also known as Stewart Platform or platform manipulator. The apparatus consists of two platforms (base and top) and six prismatic actuators in between. The main advantage of a platform manipulator is the fact that it can out-perform serial manipulators in both load capacity and precision. However, there are disadvantages and weaknesses such as limited mobility. A platform manipulator has reduced workspace compared to serial manipulators. The problem of limited workspace is solved by enabling OSCAR to change its prismatic leg positioning about the base platform.

During the course of …

Multi-Lifecycle Assessment Of Cathode Ray Tubes, Devendra Jayant Badwe

Theses

Over the past few years environmental issues and concerns have become more and more important, as they become a common part of most people's personal experience. In these regards, the electronics industry is facing substantial problems in terms of end-of-life management of its products, televisions and monitors in particular. The building blocks of this industry are usually viewed as relatively "clean". However, manufacturing by-products of the electronics industry and the disposition of electronics are becoming increasingly important technical, financial, and environmental issues.

Within the context of the above issues, environmentally responsible disposal of Cathode Ray Tubes (CRT's), which is still …

Method And Apparatus For Transferring A Person, Donald J. Smith Jr., Patrick J. Atkinson, Melissa L. Evans, Shawn P. Londo, William J. Ryan

Mechanical Engineering Patents

A method and vehicle preferably a wheelchair (10) for transporting and transferring an invalid person is described. The wheelchair has first and second frames (12 and 48) with drive wheels (18) between which is provided a chair (82) or support (83). The first frame has top and bottom sliding mechanisms (34 and 36) which are mounted by I-beam extensions (38 and 40) to the bars (24 and 26) of the first frame. The second frame has top and bottom rails (54 and 56) which are slidably connected to the sliding mechanisms of the first frame. The rails have slots (78) …

Ole Miss Engineer 1997

Ole Miss Engineer

No abstract provided.

Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Retail Strip Mall, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A series of tests were conducted in seven retail shops in a strip mall in Cocoa, Florida to examine how roof whitening would impact air conditioning load. The roof of the strip mall was conventional: unsurfaced galvanized corrugated metal with R-11 insulation suspended by purlins underneath. Below the insulation was the roof plenum which contained both the air handler and duct air distribution system. Cooling was accomplished in each shop by a dedicated direct expansion air conditioning (AC) system between 3 and 4 tons in size. Each had its air conditioning metered for half of the summer in a baseline …

Electrode Performance Test On Single Ceramic Fuel Cells Using As Electrolyte Sr‐ And Mg‐Doped Lagao3, Kevin Huang, Man Feng, John B. Goodenough, Christopher Milliken

Faculty Publications

The electrode performance of a single solid oxide fuel cell was evaluated using a 500 μm thick La_0.9Sr_0.1Ga_0.8Mg_0.2O_2.85 (LSGM) as the electrolyte membrane. Comparison of La_0.6Sr_0.4CoO_3-δ (LSCo) and La_0.9Sr_0.1MnO₃ (LSM) as cathodes showed LSCo gave an exchange current density two orders of magnitude higher than that of LSM. Comparison of CeO₂/Ni and LSGM/Ni as anodes showed a degradation of the latter with time, and studies of the anode‐electrolyte interface and the reactivity of NiO and LSGM suggest better anode …

Photovoltaic Equipment For Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Photovoltaic (solar electricity) has been used to power various equipment used in disasters. Previously, no organized program had used photovoltaic powered equipment in disasters. In response to an energy needs study with disaster relief organizations, Sandia National Laboratories for the U.S. Department of Energy sponsored the Florida Solar Energy Center to provide PV equipment to selected disaster relief organizations and evaluate its performance and acceptability. The purpose of the report is to describe the six PV-powered systems that were provided.

Optimization Of Microstructure Development During Hot Working Using Control Theory, James C. Malas Iii, W. Garth Frazier, S. Venugopal, Enrique A. Medina, Steven Madeiros, Raghavan Srinivasan, R. Dennis Irwin, W. M. Mullins, Anil Chaudhary

Mechanical and Materials Engineering Faculty Publications

A new approach for controlling microstructure development during hot working processes is proposed. This approach is based on optimal control theory and involves state-space type models for describing the material behavior and the mechanics of the process. The effect of process control parameters such as strain, strain rate, and temperature on important microstructural features can be systematically formulated and then solved as an optimal control problem. This method has been applied to the optimization of grain size and process parameters such as die geometry and ram velocity during the extrusion of plain carbon steel. Experimental results of this investigation show …

Controlling Ventilation And Space Depressurization Inrestaurants Inhot And Humid Climates, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Testing was performed in 9 restaurants to identify uncontrolled air flows and pressure imbalances, building and duct system airtightness, building air barrier location, pressure differentials, building air flow balance, and ventilation rates. All restaurants are depressurized under normal operating conditions, ranging from -1.0 to -43 pascals. Space depressurization is a function of exhaust fan flow rates, missing or undersized make-up air, intermittent outdoor air caused by the cycling of air handlers, dirty outdoor air and make-up air filters, and building airtightness. Ventilation rates were found to be high, generally exceeding ASHRAE 62-1989 minimum recommended levels. Pressure imbalances and excessive ventilation …