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Mode I Fracture And Durability Of The Cfrp -Concrete Interface Bond, David Moses Boyajian
Mode I Fracture And Durability Of The Cfrp -Concrete Interface Bond, David Moses Boyajian
Graduate Theses, Dissertations, and Problem Reports
The continual degradation of civil infrastructures worldwide has prompted the need for effective solutions, posing major challenges to those involved with reinforced concrete structures. Externally bonded fiber reinforced polymer (FRP) composites have proven to be an efficient means of rehabilitation and enhancement to both existing and new structures alike. An important issue regarding this technology that needs further exploration, however, is the strength and integrity of the interface bond---the inadequacy of which can result in premature failure of the reinforced member.;Until now, there were no available methods to rigorously evaluate the interface bond strength and integrity for concrete structures externally …
Zinc Pot Bearing Material Wear Rate As A Function Of Contact Pressure And Velocity, James M. Snider Ii
Zinc Pot Bearing Material Wear Rate As A Function Of Contact Pressure And Velocity, James M. Snider Ii
Graduate Theses, Dissertations, and Problem Reports
There are currently over 50 galvanizing lines in operation in the United States producing approximately 50 million tons per year of galvanized sheet. Frequently zinc-pot hardware fails which causes production delay, resulting in an economic loss. It takes approximately 3 hours to change the zinc-pot bearings at a downtime cost of {dollar}400/h.;To predict the performance of the submerged bearings, a large number of variables must be considered. These variables include pot chemistry, temperature, line speed and line tension. With these variables it is possible to develop a design guide for sheet mill operators to determine the most cost-effective selection of …
Characterization Of Infield Duty Cycles And Exhaust Emissions From Diesel Powered Off-Road Heavy-Duty Equipment, Jeremiah Christopher Rohrbaugh
Characterization Of Infield Duty Cycles And Exhaust Emissions From Diesel Powered Off-Road Heavy-Duty Equipment, Jeremiah Christopher Rohrbaugh
Graduate Theses, Dissertations, and Problem Reports
The objective of study was to design, develop, and evaluate techniques to measure exhaust emissions from diesel-powered off road equipment. Emissions data was collected from a Komatsu hydraulic excavator and a Caterpillar track-type tractor.;For the excavator, data was logged during in-field operation, and test cycles were created on a dynamometer test bed using this data. For the tractor, on-board emissions measurement equipment collected mass emissions rate data in field.;Vast differences were found between transient and 8-mode brake-specific test results. Transient cycle HC, CO, CO2, NO, and PM emissions were 50%, 65%, 10%, 35%, and 50% lower than 8-Mode results, respectively. …
Numerical Modeling Of Air Blast Effects On Hybrid Structures, Matthew J. Fox
Numerical Modeling Of Air Blast Effects On Hybrid Structures, Matthew J. Fox
Graduate Theses, Dissertations, and Problem Reports
Blast resistant structures are gaining increased need in today's society. This research addresses adding composite reinforcement to existing concrete structures to decrease blast damage. An upgraded material model for concrete is presented. This model, used in LS-DYNA3D, incorporates tensile damage, which allows the concrete to degrade as it is loaded. The concrete model is tested using existing unreinforced and reinforced concrete beam tests. Some beams were plain, others were externally reinforced with composites, bonded to the exterior of the beams. There is a very good correlation between the predicted and existing data. The concrete model was then used to predict …
Aerodynamic Drag Reduction Of A Racing Motorcycle Through Vortex Generation, Gerald M. Angle Ii
Aerodynamic Drag Reduction Of A Racing Motorcycle Through Vortex Generation, Gerald M. Angle Ii
Graduate Theses, Dissertations, and Problem Reports
The aerodynamic drag of a racing-class motorcycle can be accomplished through either an overall redesign of the surfaces or through some type of flow control mechanism. Due to limitations on the size of the exterior shape the flow control techniques are more practical. Small metal vanes, known as vortex generators were used in this research to mix higher energy freestream air with the lower energy boundary layer, delaying boundary layer growth and separation. In testing performed in the West Virginia University Closed Loop Wind Tunnel a maximum reduction of 118 drag counts (10.1%) was measured. Due to an abnormally high …
Measurement Of Total Hydrocarbon Emissions With Mems Using A Portable Fid And A Novel Exhaust Flow Meter, Jared Gregory Knight
Measurement Of Total Hydrocarbon Emissions With Mems Using A Portable Fid And A Novel Exhaust Flow Meter, Jared Gregory Knight
Graduate Theses, Dissertations, and Problem Reports
The objective of this study was to evaluate tools for in-field, on-board engine emissions measurements, namely, a Signal Model 3030PM hydrocarbon analyzer and McCrometer's V-Cone flow meter. The Signal Model 3030PM analyzer uses a heated flame ionizing detection scheme to measure hydrocarbons. The V-Cone is an obstructive, differential pressure flow meter that reshapes the flow profile, therefore conditioning the flow.;The Signal Model 3030PM analyzer was found to perform as well or better than the HC analyzers currently used in the FTP test cell. Besides the portability feature, the Signal Model 3030PM demonstrated better response, being able to capture the high …
Enhanced Controls For Oxy-Fuel-Fired Batch Tank During Glass Working Period, Ranjit Menon Unnikrishnan
Enhanced Controls For Oxy-Fuel-Fired Batch Tank During Glass Working Period, Ranjit Menon Unnikrishnan
Graduate Theses, Dissertations, and Problem Reports
One of the most dynamic developments in the glass industry has been the use of oxy-fuel combustion for melting glass. This new technology has not only increased the energy efficiency of the glass industry, but also has reduced its environmental impacts.;A model has been developed to take into account the effect of pulling the glass for nine hours during the working period on the reduced amount of fuel required for the batch tank, as well as the resulting transients.;The two primary goals of this thesis were to develop a transient transfer function for the batch tank and to develop an …
Design And Construction Of A Zinc Pot Bearing Material Wear Tester, Ryan Ware
Design And Construction Of A Zinc Pot Bearing Material Wear Tester, Ryan Ware
Graduate Theses, Dissertations, and Problem Reports
There are more than fifty galvanizing lines in the U.S.A. producing galvanized steel sheet by the method of pulling a steel sheet over a roller that is submerged in a liquid zinc bath. Although highly competitive, this product is very lucrative for the Steel Industry. The objective of this research is to assist the U.S. Steel Industry in becoming more competitive with foreign imports by reducing line stoppage for bearing replacement, which currently might be as long as one week to a month.;A great variety of wear and corrosion resistant zinc-pot bottom roller bearing metals and ceramics have already been …
Experimental Characterization Of The Mechanical Consequences Of A Debonded Total Hip Stem With An Unsupported Distal Tip, Keith Thomas Hustosky
Experimental Characterization Of The Mechanical Consequences Of A Debonded Total Hip Stem With An Unsupported Distal Tip, Keith Thomas Hustosky
Graduate Theses, Dissertations, and Problem Reports
Cemented total hip arthroplasty (THA) has enjoyed widespread success since its introduction over thirty years ago. Despite the successes, there are threats to the long term stability of THA, chief among them aseptic loosening of the femoral stem. Femoral component loosening is a significant problem because it prevents the efficient transfer of hip joint forces through the cement to the proximal femur. This may cause pain in the patient severe enough to warrant surgery to replace the loose component.;The predominant approach to preventing loosening of cemented THA femoral components focuses on improving the bond between the prosthesis stem and the …
Advanced Generation Niosh Automatically Deployable Rollover Protective Structure (Autorops), Khaled Ali Alkhaledi
Advanced Generation Niosh Automatically Deployable Rollover Protective Structure (Autorops), Khaled Ali Alkhaledi
Graduate Theses, Dissertations, and Problem Reports
AutoROPS have been developed recently under the sponsorship of the National Institute for Occupational Safety and Health (NIOSH) in collaboration with the Mechanical and Aerospace Engineering Department at West Virginia University. Unfortunately, numerous tractors' operators have removed the factory ROPS from the Tractors because of the lack of housing area on the tractor, which may result in frequent collision between the ROPS and low-hanging tree branches.;One main purpose of this work was to study the base of the second generation AutoROPS, to insure that the base can withstand the impact loads associated with the rollover of any farm tractor. Another …
Uncertainty Assessment For Cfd Using Error Transport Equation, Gusheng Hu
Uncertainty Assessment For Cfd Using Error Transport Equation, Gusheng Hu
Graduate Theses, Dissertations, and Problem Reports
While Computational Fluid Dynamics (CFD) is making extensive use of the power of computational technology, it is also facing a serious problem arising from the so-called numerical uncertainty. The overall uncertainty (or the global error) involved in CFD results can be due to different sources mainly contributed by (i) discretization error (or solution error due to incomplete grid convergence), (ii) iteration convergence error, (iii) grid generation errors (skewness, grid aspect and expansion ratio, coordinate transformation etc.), and (iv) round-off errors. In this study an in-depth discussion concerning these issues is presented with an emphasis on the discretization error in regard …
Study Of Natural Gas Vehicles (Ngv) During The Fast Fill Process, Eric Paul Shipley
Study Of Natural Gas Vehicles (Ngv) During The Fast Fill Process, Eric Paul Shipley
Graduate Theses, Dissertations, and Problem Reports
Natural gas is being used as an alternative fuel to gasoline. Natural gas vehicle (NGV) refueling stations, however, are not able to guarantee a 100% full fill to NGV's. A system was designed and built to better understand the characteristics of CNG during the fill process. Useful characteristics of CNG during the fill process are temperature, pressure, and flow rate, as well as, total volume dispensed. CNG is dispensed to an NGV through a process known as the fast fill process, since it is completed in less than five minutes. The system that was built is transportable, which means that …
Experimental Study Of Thermosiphon Performance, Sumeeth S. Sivanagere
Experimental Study Of Thermosiphon Performance, Sumeeth S. Sivanagere
Graduate Theses, Dissertations, and Problem Reports
A model single phase loop thermosiphon was designed and built such that velocity profiles and heat transfer rates could be studied by obtaining temperature data, along with a detailed set of non-intrusive Laser Doppler Velocimetry measurements. The quantities measured were the instantaneous velocity profiles for the water flow. These velocities were then reduced into sets of mean and root mean square velocities, for different angles of tilt of the experimental setup. Nominal heating and cooling rates were held constant.;The single phase thermosiphon consisted of an aluminum flow loop, fitted with a test section made of Plexiglas, that was rectangular in …
Aging Model For Commercial Polymers, Kevin J. Ford
Aging Model For Commercial Polymers, Kevin J. Ford
Graduate Theses, Dissertations, and Problem Reports
Physical aging of polyvinyl chloride, high-density polyethylene, and polyester reinforced with polyester fibers specimens have been investigated. These materials are commercially available and are currently used in trenchless relining of sewer pipes. The analysis uses the effective-time theory and time-temperature superposition (TTSP) methods proposed by Struik, as well as variations of these methods, as proposed by Chai and McCrum, Guerdoux et al. and others. The creep data generated by this study show that the time-dependent creep properties of these materials can be modeled within experimental error with slight changes to the above methods. To predict the creep behavior of full-scale …
Long-Term Creep Of Encased Polymer Liners, Shalini Rangarajan
Long-Term Creep Of Encased Polymer Liners, Shalini Rangarajan
Graduate Theses, Dissertations, and Problem Reports
Due to increasing costs and inconveniences in replacing deteriorated sewer pipelines by conventional excavation methods, the trenchless or 'no-dig' technology is being extensively used. In trenchless technology, a polymer or reinforced polymer is applied to the inside of the deteriorated host pipe to prevent ground water from seeping into the sewer pipelines. In this work, a testing method was developed to determine the long-term creep behavior of encased polymer liners.;Short-term tests, following the ASTM D790 procedure, were conducted on pipe liner samples to determine the initial elastic modulus and compare it to the elastic modulus obtained from long-term testing of …
Design Verification Of Expansion Joints Using Finite Element, Khoi Trinh
Design Verification Of Expansion Joints Using Finite Element, Khoi Trinh
Theses
An elastomeric expansion joint is a flexible connector fabricated of elastomers, fabrics and, in some cases, metallic reinforcements. The function of the expansion joint is to relieve stress in piping systems due to thermal fluctuation, vibration and/or piping settlement. In safety related applications, such as piping systems in nuclear power plants where the performance of the expansion joint is critical, the design must be verified to ensure all requirements are met. The objective of this project is to implement finite element as a design tool to aid the design and analysis of the expansion joints. An extensive study of a …
Switching Voltage Of Micro-Beam Actuators - Analysis, Fabrication And Test, Eui-Shin Kim
Switching Voltage Of Micro-Beam Actuators - Analysis, Fabrication And Test, Eui-Shin Kim
Theses
This thesis introduces an analysis, fabrication and testing of a //-cantilever. First, the theoretical method used to analyze the deflection of a micro-beam with two supports and switching voltage is introduced. The results are compared to an I-DEAS simulation. Second, the theoretical approach is modified in order to be suitable for the actual //- cantilever beam model because the material, geometry and the type of structure have been changed. The switching voltage of each beam size is predicted using the modified method. Third, a series of single //-cantilever beams are designed according to the MEMS design rules. Using the facilities …
Combustion Analysis And Particulate Mutagenicity Characterization For A Single-Cylinder Diesel Engine Fueled By Fischer -Tropsch Derived Liquids, Michael Hayden Mcmillian
Combustion Analysis And Particulate Mutagenicity Characterization For A Single-Cylinder Diesel Engine Fueled By Fischer -Tropsch Derived Liquids, Michael Hayden Mcmillian
Graduate Theses, Dissertations, and Problem Reports
Further growth of diesel engines in the light-duty and heavy-duty vehicular markets is closely linked to the potential health risks of diesel exhaust. Cleaner burning fuels, such as those derived from natural gas via the Fischer-Tropsch (FT) process, offer a potentially economically viable alternative to standard diesel fuel. As part of this study, a two-liter, single-cylinder, four-stroke direct-injected engine was instrumented for in-cylinder pressure measurements. The emissions and performance data from engine operation with Federal low sulfur No. 2 diesel fuel (DF) and natural gas derived FT fuel were compared. Also as part of the study, an investigation was carried …
Manufacture And Rehabilitation Of Guardrail Posts Using Composite Fabrics, Ram Chamarthy
Manufacture And Rehabilitation Of Guardrail Posts Using Composite Fabrics, Ram Chamarthy
Graduate Theses, Dissertations, and Problem Reports
The West Virginia Department of Transportation (WVDOT) uses approximately 50,000 wood and 200,000 steel guardrail posts on an annual basis. The need to develop guardrail posts made of a different material is motivated by the high cost of steel, along with the greater difficulty associated with driving large diameter wood posts.;The primary objective of this study was to develop a Glass Fiber Reinforced Polymer (GFRP) wood post that is more cost effective than a steel post and has smaller diameter than a conventional wood post. Another objective was to develop a portable fabric-wrapping machine for field applications.;Unwrapped and GFRP wrapped …
Chebyshev Pseudospectral Methods For Conservation Laws With Source Terms And Applications To Multiphase Flow, Scott Alan Sarra
Chebyshev Pseudospectral Methods For Conservation Laws With Source Terms And Applications To Multiphase Flow, Scott Alan Sarra
Graduate Theses, Dissertations, and Problem Reports
Pseudospectral methods are well known to produce superior results for the solution of partial differential equations whose solutions have a certain amount of regularity. Recent advances have made possible the use of spectral methods for the solution of conservation laws whose solutions may contain shocks. We use a recently described Super Spectral Viscosity method to obtain stable approximations of Systems of Nonlinear Hyperbolic Conservation Laws. A recently developed postprocessing method, which is theoretically capable of completely removing the Gibbs phenomenon from the Super Spectral Viscosity approximation, is examined. The postprocessing method has shown great promise when applied in some simple …
Modeling The Pultrusion Process To Obtain Low Void Fraction Composites, Adam Douglas Freed
Modeling The Pultrusion Process To Obtain Low Void Fraction Composites, Adam Douglas Freed
Graduate Theses, Dissertations, and Problem Reports
This work was directed at improving the strength and durability of pultruded composites. Pultruded composites are being used in an increasingly wider range of applications, and, as a result, a higher demand has been placed on the performance capabilities of the various components.;One target area for improving composites is the fraction of voids in the final product. The presence of voids in a composite decreases the Interlaminar Shear Strength, provides a site for the formation of fractures, and increases the susceptibility of the part to outside contaminants.;In this work, the various steps of the pultrusion process are analyzed in order …
Design, Construction And Testing Of An Innovative Mechanism For Manual Wheelchair Propulsion, Thomas S. Burke Jr.
Design, Construction And Testing Of An Innovative Mechanism For Manual Wheelchair Propulsion, Thomas S. Burke Jr.
Graduate Theses, Dissertations, and Problem Reports
The concern for people with disabilities who are users of wheelchairs has become a dynamic research area in the past several years. As part of this research, new and innovative mechanisms that give the manual wheelchair users a mechanical advantage, and allow them to operate a standard wheelchair with less effort and muscle strain are being developed.;An innovative mechanism has been conceived, designed, built, and tested. It allows the user to propel a standard wheelchair in both the push and pull strokes of the handle. This new design will allow for a more symmetric muscle development of the shoulder and …
Nucleation And Coagulation Of Particulate Matter Inside A Turbulent Exhaust Plume Of A Diesel Vehicle, Donghee Kim
Nucleation And Coagulation Of Particulate Matter Inside A Turbulent Exhaust Plume Of A Diesel Vehicle, Donghee Kim
Graduate Theses, Dissertations, and Problem Reports
The objective of this study is to develop a physical model to accurately predict the nucleation, coagulation, and dynamics of particulate matter emission from diesel-fueled engines. The uniqueness of this research is that measured particulate matter (PM) size distribution data is not required a priori to solve the nucleation/coagulation equations; instead the PM concentration is predicted based on the fuel sulfur content, fuel to air ratio, exhaust flow rate, and the ambient conditions. This study presents the CFD modeling of an exhaust plume dispersed from a stack pipe of a tractor truck powered by a 330 HP diesel engine. This …
An Investigation Into The Sources Of Vehicle Tire Noise, John Paoff
An Investigation Into The Sources Of Vehicle Tire Noise, John Paoff
Theses
Noise produced by a rolling tire on pavement has plagued automakers for years due to its complexity. Tire noise is dependent on many things such as tire material, tire construction, road surface texture, etc. In this investigation, an acoustical approach to modeling tire noise is presented. Based on the mechanics of a rotating tire, acoustical models can be developed. This, along with some acoustical analysis, leads to mathematical models that one can utilize in order to predict the noise that the tire will produce. These models will provide a good basis and starting point for reduction of tire noise and …
Analysis Of The Droplet Size Reduction In A Pmdi To The Addition Of A Turbulence Generating Nozzle, Michael Medlar
Analysis Of The Droplet Size Reduction In A Pmdi To The Addition Of A Turbulence Generating Nozzle, Michael Medlar
Theses
Pharmaceutical inhalation aerosol technology has become an important therapy for the treatment of both respiratory and non-respiratory illness. Targeting therapeutic aerosols to the small airways of the lung can effectively treat many of these diseases. Delivery of the therapeutic agent directly to the site of action, for cases involving respiratory diseases, ensures an adequate therapeutic level of the drug is reached, without leading to side effects due to high systemic concentrations. For non-respiratory diseases, the periphery of the lung offers enormous surface area (approximately 100m2) for rapid absorption into circulation. In either case, the appropriate spray characteristics (0.5 um
Vehicle Simulations Of Fuel Economy For An Automatic Transmission And A Ratio Limited Continuously Variable Transmission, Hemant Suthar
Vehicle Simulations Of Fuel Economy For An Automatic Transmission And A Ratio Limited Continuously Variable Transmission, Hemant Suthar
Theses
An automatic transmission (AT) of a vehicle was compared with a ratio limited Continuously Variable Transmission (CVT). Dynamic model of a passenger car was simulated to compare the overall efficiency of the vehicle equipped with these different types of transmissions. The overall efficiencies were calculated in terms of fuel consumption of the vehicle. The results are based on the Environmental Protection Agency's (EPA) city and highway driving cycles. A Modular approach is taken to model an existing vehicle. The complete model is subdivided into an engine model, road load model, throttle and brake pedal models, and a transmission model. The …
Deep Structures Wet Etched Into Lithium Niobate Using A Physical Mask, Andrew Randles
Deep Structures Wet Etched Into Lithium Niobate Using A Physical Mask, Andrew Randles
Theses
The present work is an investigation and characterization of a new technique for etching and masking Lithium niobate (LiNb03) to realize high aspect ratio trenches. LiNb03 is a single crystal optically clear (from 350 nm to 5 micometer wavelength), piezoelectric material. It is also inert to most reactants and has a high curie temperature (the temperature that a material loses its piezoelectric effect). These properties allow LiNb03 to be used as a sensor or actuator in harsh environments. To realize this actuator/sensor a multilevel lithium niobate deep etching technique is currently unavailable. The present work uses a chrome gold mask …
Feasibility Study Of A Permanently Implanted Prosthetic Hand, Matt Williams
Feasibility Study Of A Permanently Implanted Prosthetic Hand, Matt Williams
Theses
The feasibility of a permanently implanted prosthetic hand was evaluated from both an internal biocompatibility and exterior mechanics point of view. A literature review of the issues involved in permanent implantation of a percutanious device was performed in the areas of bone interaction and fixation and neural interface control. A theoretical implant was designed for a 90th percentile male, using an HA-G-Ti composite material to provide a permanent base to which the hand could attach. Using a radial implant length of 1.87 inches and an ulna implant length of 1.32 inches, the simulated implant could withstand a push out force …
A Demonstration In Communication And Task Completion Between Two Autonomous Robots, Adam Renzi
A Demonstration In Communication And Task Completion Between Two Autonomous Robots, Adam Renzi
Theses
The world of robotics is rapidly changing. No more are the days of robotics classes being taught that focus merely on highly industrial, automation robots. Today's robotics is focusing more and more on microcontrollers and their implementation into everyday life. Miniature robotics and how it is implemented to make common tasks easier is becoming the focus of many robotics classes across the world. Microcontrollers allow users to control several inputs and outputs to complete somewhat difficult tasks. In today's society, one might find a microcontroller in anything from a computer to the average household toaster. As time has passed, microcontrollers …
Experimental Evaluation Of Impulse Turbine Designs For Chain Testing Systems, Aaron Donlon
Experimental Evaluation Of Impulse Turbine Designs For Chain Testing Systems, Aaron Donlon
Theses
There are several ways to test automotive timing chains for wear in a laboratory environment. One novel method proposed by Borg-Warner Morse TEC uses fluid jets striking an impeller blade. The momentum of the oil striking and deflected by the impeller blade is used to produce a torque. This torque is transmitted to the system through the timing chain. A previous theoretical design study (conducted elsewhere) evaluated some of the design factors as they related to machine performance and ultimately to the torque loads applied to the chain. From this theoretical study came the design for two novel bucket and …