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Finite Element Damage Modeling Of Plain Weave Fabrics, Kaarthik K. Sikkil
Finite Element Damage Modeling Of Plain Weave Fabrics, Kaarthik K. Sikkil
Graduate Theses, Dissertations, and Problem Reports
Plain weave fabrics are used as reinforcements in composites in order to obtain improved inter-laminar properties. But these advantages are at the cost of reduced stiffness and strength in the in-plane directions. Therefore, it is important to study the mechanical behavior of such composites. In this work, the geometrical model needed for finite element discretization of the plain weave fabrics are developed for three configurations---single lamina, iso-phase, and out-of-phase. Next, a procedure to determine the longitudinal elastic modulus under tensile loading is presented. Then, a meso level damage model is used for predicting the inelastic tensile behavior of the fabrics. …
Characterization Of Exhaust Emissions From Catalyzed Trap-Equipped Non-Road Heavy-Duty Diesel Engines, Vinay Nagendran
Characterization Of Exhaust Emissions From Catalyzed Trap-Equipped Non-Road Heavy-Duty Diesel Engines, Vinay Nagendran
Graduate Theses, Dissertations, and Problem Reports
An emissions and engine performance study was conducted to explore the effects of ultra low sulfur fuels on an off-road, heavy-duty engine retrofitted with catalyzed traps. The study was conducted, on an 8 cylinder, mechanically controlled Caterpillar 3408, rear engine of a Scraper. An in-field transient duty cycle was determined by logging the engine speed and torque using an Electronic Control Unit (ECU) communication adapter on the Scraper. The test fuels included California Air Resources Board (CARB) off-road diesel fuel, Fischer-Tropsch and Emission Control Diesel-1 (ECD1) diesel fuels. The engine was retrofit with two different types of diesel particulate filters …
One-Dimensional Transient Numerical Modeling Of A Micro-Power Generation System, Emre Tatli
One-Dimensional Transient Numerical Modeling Of A Micro-Power Generation System, Emre Tatli
Graduate Theses, Dissertations, and Problem Reports
Two core modules of a more comprehensive model for analyzing the flow of fluids in a hybrid system including a fuel cell are developed. First part consists of a new procedure for scaling turbomachinery maps. In the last few decades, the sizes of turbomachinery have been getting smaller and smaller for various purposes. New designs have pushed the limits of power generation to be in more compact sizes, which lead to smaller compressors and turbines. For new designs, it is important to know how the turbomachinery in the system will behave at certain conditions. But it is not practical to …
Aerodynamic Force And Moment Balance Design, Fabrication, And Testing For Use In Low Reynolds Flow Applications, Corey Abe
Theses
The aerodynamic performance of airfoils operating at Reynolds numbers below 105 has been of interest due to its variety of applications in areas such as unmanned remotely piloted vehicles, small-scale machinery, and more recently, Micro Air Vehicles (MAV's). Design and testing of airfoils to meet these applications is challenging due to the lack of experimental data in low Reynolds flow, compared to airfoils tested at higher Reynolds numbers. Two mechanical balance devices are designed and evaluated to provide a quick and simple method to test small airfoil aerodynamic loads. Each device measures two degrees of freedom; a force balance measures …
Potential Field Theory And Its Applications To Classical Mechanical Problems, Shannon Rae Stillwagon
Potential Field Theory And Its Applications To Classical Mechanical Problems, Shannon Rae Stillwagon
Graduate Theses, Dissertations, and Problem Reports
Advances in many scientific fields are expected to come from work in nanotechnology. Engineering at nano-scales presents novel problems that classical mechanics cannot solve. Many engineers are uncomfortable designing at this level because classical or continuum mechanics does not apply and quantum mechanics is said to apply in a tangible way. There are unique opportunities to contribute to the design, controls, and analysis of systems that are particularly suited to mechanical engineering. Within the derivations of classical mechanics are assumptions that limit its use to bulk engineering. These assumptions are examined to determine what principles can be extended to smaller …
Effect Of Rate Of Sumping On Fragmentation Process In Laboratory Rotary Cutting Simulator, Muralidharan Venkataraman
Effect Of Rate Of Sumping On Fragmentation Process In Laboratory Rotary Cutting Simulator, Muralidharan Venkataraman
Graduate Theses, Dissertations, and Problem Reports
This study was done to examine the fragmentation process and to improve sumping. Research has demonstrated that specific energy and specific respirable dust must be kept minimum to produce the optimum parameters of the rock/coal breakage process and to attain maximum sumping. There are three major elements affecting the efficiency of the cutting head namely: (1) Geometry and size of the cutting tool, (2) Geometry of the drum and lacing and arrangements of the tools on the drum and (3) Effect of rate of advance/dynamic impacts. The emphasis is made on the rate of advance utilizing a miniature rotary cutting …
Analysis Of A Curved Buoyant Jet In An Enclosure Using Les, Allen E. Badeau Jr.
Analysis Of A Curved Buoyant Jet In An Enclosure Using Les, Allen E. Badeau Jr.
Graduate Theses, Dissertations, and Problem Reports
The objective of this study is to investigate curved buoyant jets in an enclosure using Large Eddy Simulation (LES) methods with an Implicit Turbulent Model (ITM). To accomplish this goal, a numerical solver was written, named DREAMRTM, which is capable of solving three dimensional, transient flows using an accurate monotonic and non-oscillatory upwinding scheme. The three-dimensional Navier-Stokes equations are solved in Cartesian coordinates, with the control volume approach being implemented on a staggered grid. The numerical scheme uses a fractional time step method, with the overall spatial and temporal accuracy being second order.;In ITM simulations, there is no explicit subgrid-scale …
Real-Time Measurement Of Oxides Of Nitrogen From Heavy-Duty Diesel Engines, Aparna Aravelli
Real-Time Measurement Of Oxides Of Nitrogen From Heavy-Duty Diesel Engines, Aparna Aravelli
Graduate Theses, Dissertations, and Problem Reports
New emissions regulations and performance requirements imposed on modern diesel engines encourage the development of improved tools for emissions measurements. This study investigated one of the improved tools for NOx emissions measurement. Objectives of this thesis included measurement, comparison and prediction of NOx emissions from heavy-duty diesel engines using two different NOx analyzers. Steady state and transient tests were conducted on six heavy-duty diesel engines in the WVU Engine and Emissions Research Center (EERC). NOx emissions were measured using a conventional Rosemount NOx analyzer and a Cambustion fast response NOx analyzer. The Rosemount analyzer sampled dilute emissions whereas the fast …
Crack Detection Technique For Reinforced Concrete Bridge Decks, Indumathi Chera
Crack Detection Technique For Reinforced Concrete Bridge Decks, Indumathi Chera
Graduate Theses, Dissertations, and Problem Reports
This study describes the instrumentation and test results of a reinforced concrete bridge deck constructed on 3-span continuous steel girders. The instrumented bridge is located in Evansville, West Virginia at the intersection of US Route 50 East and WV 92 South. An instrumentation system is developed and implemented specifically to measure and monitor the growth of cracks along the wheel path. The system consists of 30 crack-meters embedded in concrete over the bottom layer of the reinforcement. The crack-meter readings are automatically collected every 20 minutes together with the readings from other sensors that were placed in concrete and on …
Parametric Modeling Of Bolted Joints Between Components Made Of Particulate Composite Materials, Vasudha Goteti
Parametric Modeling Of Bolted Joints Between Components Made Of Particulate Composite Materials, Vasudha Goteti
Graduate Theses, Dissertations, and Problem Reports
Particulate metal matrix composites (MMC) exhibit higher stiffness, strength and wear resistance compared to metal alloys. They exhibit superior compressive and buckling strength because of their higher plastic modulus. MMC's can operate at very higher temperatures than fiber-reinforced polymer composites. Their isotropic behavior and forming ability by conventional methods makes them a better choice for low-cost applications. They have good thermal conductivity, high electrical conductivity and low thermal expansion.;The main objective of this study is to predict numerically the stress distributions around the hole in a bolted joint made of particulate metal matrix composite and to investigate the associated load …
Laboratory Experiments In Thermal Sciences, Christopher K. Jackson
Laboratory Experiments In Thermal Sciences, Christopher K. Jackson
Graduate Theses, Dissertations, and Problem Reports
Study of the basic sciences (chemistry, biology, physics, etc.) requires experimental verification to support the theory developed in the classroom. Engineering solutions are the same in their need for verification. In an academic environment this verification comes in the form of laboratory courses. The link to applications is equally important as the demonstration of theory. This is especially true for engineering disciplines due to the nature of tasks engineers are expected to successfully complete in industry. It is vital for the engineer's career that he/she can successfully apply the background theory learned in university study to real world applications.;The Department …
Characterization Of In-Use Emissions From On-Highway Heavy-Duty Diesel Engines, Mohan Krishnamurthy
Characterization Of In-Use Emissions From On-Highway Heavy-Duty Diesel Engines, Mohan Krishnamurthy
Graduate Theses, Dissertations, and Problem Reports
Class-8 trucks with GVWR of 80,000 lbs were tested on different driving routes and in-use brake-specific emissions of NOx and CO2 data were collected using the West Virginia University's Mobile Emissions Measurement System (MEMS). An uncertainty analysis was performed on the MEMS and it was determined the maximum possible error in the measurement of brake-specific emissions of NOx was 8% and CO2 was 6%.;A modal analysis indicated that the cruise mode comprised 70% of the time that the vehicle spent in the Not-to-Exceed (NTE) zone while the acceleration and deceleration modes about 20% and 10% respectively.;In order to reduce the …
Fatigue Response Of Fabric Reinforced Polymeric Composites, Venkatakrishnan Natarajan
Fatigue Response Of Fabric Reinforced Polymeric Composites, Venkatakrishnan Natarajan
Graduate Theses, Dissertations, and Problem Reports
Fiber Reinforced Polymeric (FRP) Bridge decks have been an active area of research for the past 10 yrs. In order to better understand the long term efficiency and reliability of FRP bridge decks, and to develop design and test specifications, laboratory testing and characterization of the deck systems and the FRP material, is necessary. Majority of the FRP deck systems available to date are made of glass-reinforcing fibers in the form of fabrics, mats, rovings, etc. Currently, the fatigue response of multidirectional composite is not readily available in the literature and much work needs to be done to understand the …
Long-Term Performance Of Pot Hardware In Continuous Galvanizing Lines, Venkatesh Parthasarathy
Long-Term Performance Of Pot Hardware In Continuous Galvanizing Lines, Venkatesh Parthasarathy
Graduate Theses, Dissertations, and Problem Reports
Preliminary comparative wearing tests were conducted on wearguard bearing system against CF3M (casting version of 316L steel), with tungsten carbide laser clad coating, at 30% and 50% production line tension. Tests were also conducted on Stellite 6 against Tribaloy T 400 at 50% production line tension. For each test, periodic measurements of wearing rate, surface microstructure and surface hardness were carried out. An unique dross build-up setup which consists of two sleeves counter rotating against each other was designed to simulate the dross build-up in production line. The chemical composition of the dross material formed and change in sleeve microstructures …
Dynamic Response Evaluation Of Fiber-Reinforced Composite Bridge Decks And Bridges, Chandra Sekhar Jinka
Dynamic Response Evaluation Of Fiber-Reinforced Composite Bridge Decks And Bridges, Chandra Sekhar Jinka
Graduate Theses, Dissertations, and Problem Reports
Fiber Reinforced Polymer (FRP) composite bridge decks are gaining attention of bridge owners because of their light self weight, corrosion resistance and ease of installation. The lighter weight and lower stiffness of the FRP decks combined with the lower level of damping (than concrete) can lead to excessive deck vibrations and may substantially increase the dynamic amplification of induced stress and deflections. Also, a global NDE technique using dynamic characterization is necessary to ensure the long term performance of FRP bridges. Therefore, an extensive study on FRP decks and FRP bridges is carried out both at laboratory and in the …
Characterization Of New Particulate Mmc Materials And Bolted Joints Through Applicable Astm Standards, Vinu Zacharia Mathew
Characterization Of New Particulate Mmc Materials And Bolted Joints Through Applicable Astm Standards, Vinu Zacharia Mathew
Graduate Theses, Dissertations, and Problem Reports
Particulate reinforced metal matrix composites (PRMMC) comprise a new class of materials whose properties can be adjusted to suit a particular application. The main purpose of producing PRMMC is to achieve lightweight materials with added properties like high stiffness, high ultimate strength and hardness.;In this study we deal with PRMMC manufactured by a novel technology involving the pressure less infiltration of aluminum into a mass of ceramic reinforcement particles. Basic tests like tension test, three point bending test, hardness tests and coefficient of thermal expansion are conducted according to the ASTM standards in order to characterize the material. All these …
Corrosion Of High-Chromium And Conventional Steels Embedded In Concrete, Vijayakumar Nachiappan
Corrosion Of High-Chromium And Conventional Steels Embedded In Concrete, Vijayakumar Nachiappan
Graduate Theses, Dissertations, and Problem Reports
Corrosion of steel in concrete structures sometimes led to the unexpected failure of the concrete bridges in United States before their intended service life. High-chromium steel has been developed as a replacement for conventional steel in concrete because it may have a capability to retard the corrosion rate. In the present study, high-chromium and conventional steels were subjected to accelerated corrosion, and compared for their corrosion performance under chloride environment.;Corrosion rates of high-chromium and conventional steel rebars were compared by conducting two studies. One was with concrete blocks and the other was with bare steel rebars. In the former study, …
Identification And Prediction Of Nonlinear Dynamics, Andrew Dick
Identification And Prediction Of Nonlinear Dynamics, Andrew Dick
Theses
Chaos theory and associated analyses are being applied to a growing number of disciplines. Studies of biological and ecological systems have shown the widest application of chaotic analyses thus far. When studying these systems, it is often only possible to measure a subset of the system's many variables. To effectively perform a number of the analyses required to study a chaotic system, it is necessary to identify a complete strange attractor for the system. Consequently, it is necessary to reconstruct the system's strange attractor from the available data. Many different methods exist for reconstructing strange attractors, but the effectiveness of …
Experimental Study Of Heat Transfer, Pressure Drop, And Critical Heat Flux In An Oil Heated Minichannel, Levi Campbell
Experimental Study Of Heat Transfer, Pressure Drop, And Critical Heat Flux In An Oil Heated Minichannel, Levi Campbell
Theses
Heat transfer, pressure drop, and critical heat flux are experimentally recorded for flowing water in a single 706 pm circular copper channel 158.75 mm long. Heat is supplied by heat transfer oil at specified temperatures to a helical channel in the test section. In contrast to other current experimental techniques for flow boiling in small diameter tubes, a uniform temperature boundary condition is employed rather than a constant heat flux condition. The principal results of these experiments are two-phase flow boiling heat transfer rates, a comparison of two data acquisition methods and their effect on the value of CHF, and …
Acoustic Emission Evaluation Of Frp Composite Specimens In Tension And Bending, Ryan Edward Arnold
Acoustic Emission Evaluation Of Frp Composite Specimens In Tension And Bending, Ryan Edward Arnold
Graduate Theses, Dissertations, and Problem Reports
Fiber Reinforced Polymer composites are relatively new to the bridge construction industry. One of the challenges to greater usage is the lack of a nondestructive method to accurately evaluate them. Nondestructive evaluation of FRP composite structures using Acoustic Emissions was conducted. Seven tension specimens and fifteen bending specimens from three different FRP manufacturers were tested. The hand-laid tension specimens produced at WVU were tested following ASTM D3039. The bending specimens were tested according to ASTM D790.;AE parameters were analyzed, and connections were found between them and the loading quarter of the specimens along with the damage zone of the specimens. …
Dowel-Concrete Contact Characteristics, Sri Vani Sirisha Motamarri
Dowel-Concrete Contact Characteristics, Sri Vani Sirisha Motamarri
Graduate Theses, Dissertations, and Problem Reports
In this thesis, the dowel-pulling force and the dowel-concrete coefficient of friction were measured using a novel laboratory setup of vibrating wire strain gauges embedded in both the dowel and concrete. The gages are set to measure the shrinkage strain induced in the concrete that surrounds the dowel as it cures causing the solidified concrete to clamp on the steel dowel. The measurements reveal that radial strain in concrete around the dowel is not uniform along the dowel circumference. As the dowel is pulled out of concrete, both the dowel-pulling force and the elastic strain recovery in concrete are recorded …
Bone Fracture Toughness Of Estrogen Deficient Rabbits, Matthew S. Smith
Bone Fracture Toughness Of Estrogen Deficient Rabbits, Matthew S. Smith
Graduate Theses, Dissertations, and Problem Reports
Bone mass is commonly used as an indicator of fracture risk. It has been shown in numerous studies that bone loss causes increased bone fragility and risk of fracture. It has also been shown that 50% of patients with osteoporotic vertebral compression fractures have the same bone mass as normal age matched controls. Thus, bone mass alone is not the only indicator of bone quality and ability to resist fracture.;The objective of this study was to qualitatively assess bone's mechanical and histomorphometric changes with drug treatment, and estrogen deficiency, using fracture toughness, femoral neck fracture and histomorphometric analysis in an …
Simulation Of A Vertical Ground-Coupled Heat Pump System With Optimal Ground Loop Design, Krishna C. Adivi
Simulation Of A Vertical Ground-Coupled Heat Pump System With Optimal Ground Loop Design, Krishna C. Adivi
Graduate Theses, Dissertations, and Problem Reports
As the natural resources for conventional energy will steadily diminish in the future, it becomes necessary to search for alternate sources of energy. One of those sources includes the geothermal energy, which is defined as the thermal energy found in the earth's crust. Ground coupled heat pumps (GCHP) consist of a water-to-air or water-to-water heat pump, a circulator pump, a buried pipe grid and an interconnecting header. Heat is extracted from or rejected to the ground through this buried pipe grid that circulates a heat transfer fluid such as water or a water/antifreeze solution. Energy is spent to run the …
Numerical Simulation For Parametric Study Of A Two -Stroke Compression Ignition Direct Injection Linear Engine, Ehab F. Shoukry
Numerical Simulation For Parametric Study Of A Two -Stroke Compression Ignition Direct Injection Linear Engine, Ehab F. Shoukry
Graduate Theses, Dissertations, and Problem Reports
A time based numerical simulation program was built at West Virginia University to simulate the operation of a two-stroke compression ignition direct injection linear engine. The two-stroke linear engine consists of two pistons connected together with a yoke and allowed to move freely according to the frequent combustion that takes place in response to fueling and load applied along the full stroke of the internal combustion engine. The simulating program used a series of dynamic and thermodynamic equations that were solved simultaneously to predict the performance and analyze the different factors affecting the operation of the two-stroke compression ignition linear …
Comparison Of Heavy-Duty Diesel Engine Emissions Between An On-Road Route And Engine Dynamometer Simulated On-Road Cycle, John Curtis Gibble
Comparison Of Heavy-Duty Diesel Engine Emissions Between An On-Road Route And Engine Dynamometer Simulated On-Road Cycle, John Curtis Gibble
Graduate Theses, Dissertations, and Problem Reports
Heavy-duty diesel engines are known to emit concentrations of harmful compounds of oxides of nitrogen (NOx) and particulate matter (PM). As a means of emissions control, engine dynamometer certification is currently employed. Current certification cycles provide for standardized comparisons, but may not be indicative of real-world emissions. Accurate in-use emissions testing would provide more realistic engine emissions values.;To examine the accuracy of the West Virginia University Mobile Emissions Measurement System (MEMS), on-road emissions tests were performed with six different diesel-powered vehicles. Exhaust species measured by MEMS were NO x and CO2, reported on a brake-specific basis. Information obtained during on-road …
Performance Of Doweled Concrete Joints Subjected To Fatigue Loading, Appalaraju Vetsa
Performance Of Doweled Concrete Joints Subjected To Fatigue Loading, Appalaraju Vetsa
Graduate Theses, Dissertations, and Problem Reports
Distress in concrete transverse joints is often initiated due to the development of excessive stresses at the dowel/concrete interface. Recent studies indicated the existence of two types of stresses i.e. compressive stresses at the top and bottom of the dowel and tensile stresses at both sides of the dowel bar. These stresses are the primary concern as they are believed to be a major factor for the failure of rigid pavement joints.;Dr. Shoukry invented a new dowel design named shokbar that significantly reduces the magnitude of such contact stresses. The primary objective of this study is to characterize the behavior …
Development Of Instrumentation For Acoustic Monitoring, Deepak Mehra
Development Of Instrumentation For Acoustic Monitoring, Deepak Mehra
Graduate Theses, Dissertations, and Problem Reports
This thesis describes a source/sink flow acoustic wave sensor for the identification of leaks in gas pipelines. One of the many type of signals associated with the high velocity gas flowing out of a hole in the pipeline is the ramp or step pressure drop.;A large 3-inch diameter diaphragm was installed in an attempt to detect the low frequency waves associated with a leak. This diaphragm with source or sink flow through a 17mm internal diameter pipe acts as a pressure signal amplifier.;The deflection of the diaphragm due to the amplified force can be measured with a strain gage whose …
Locomotive Emissions Effects Due To Engine Configuration, Nicholas P. Amandus
Locomotive Emissions Effects Due To Engine Configuration, Nicholas P. Amandus
Graduate Theses, Dissertations, and Problem Reports
There are two studies reported in this document. The first study tested a General Electric C39-8 (Norfolk Southern Engine Number 8678) locomotive and a General Electric D8-40C (Norfolk Southern Engine Number 8692) locomotive, which were equipped with General Electric Model 7FDL16L6 diesel engines with mechanically controlled fuel injection. The objective of this study was to determine if a mechanically fuel injected diesel locomotive engine could be made to meet the EPA Tier 0 emissions limits without a substantial loss in fuel economy by retarding the injection timing and installing a more efficient turbocharger. The first locomotive was equipped with a …
Evaluation Of Regulated Emissions From Heavy-Duty Diesel Vehicles In The South Coast Air Basin, Thomas M. Buffamonte
Evaluation Of Regulated Emissions From Heavy-Duty Diesel Vehicles In The South Coast Air Basin, Thomas M. Buffamonte
Graduate Theses, Dissertations, and Problem Reports
It is important to know how heavy-duty diesel vehicles affect the air quality in the United States. Twenty-five heavy-duty diesel vehicles in the CRC E55/59 Phase I study were tested on the Urban Dynamometer Driving Schedule (UDDS), AC50/80 and the Heavy Heavy-Duty Diesel Truck (HHDDT) Schedule using the West Virginia University Transportable Emissions Laboratory (TransLab). Every vehicle in the CRC E55/59 Phase I study was tested at 30,000 lbs. (Unladen) and 56,000 lbs. (Laden) on the HHDDT, except for one tanker truck that was tested at 45,000 lbs (Laden). Also, the first thirteen vehicles in the study were tested on …
Dynamic Modeling And Control Of A Proton Exchange Membrane Fuel Cell As A Distributed Generator, Padmanabhan Srinivasan
Dynamic Modeling And Control Of A Proton Exchange Membrane Fuel Cell As A Distributed Generator, Padmanabhan Srinivasan
Graduate Theses, Dissertations, and Problem Reports
This research concentrated on the modeling and control of a Proton Exchange Membrane (PEM) fuel cell in a deregulated electric power system. The PEM fuel cell is a Multiple Input Multiple Output (MIMO) system with various dynamic states. In most previous model studies, the stack temperature of a fuel cell was considered to be constant. For long duration short transient and analysis, the stack temperature should be considered a variable. A derived dynamic model for the PEM fuel cell was analyzed using MATLAB/SIMULINK. Power generation characteristics of the PEM fuel cell were presented. Performance of the PEM fuel cell under …