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Designing And Modeling A Torque And Speed Control Transmission (Tsct), John Allen Anderson
Designing And Modeling A Torque And Speed Control Transmission (Tsct), John Allen Anderson
Graduate Theses, Dissertations, and Problem Reports
Near term Hybrid Electric Vehicles (HEVs) generally employ current automotive transmissions. These automatic and manual transmissions are based on designs that are many years old. These older transmission designs do not allow multiple power inputs/outputs to be connected to the transmission. These types of designs significantly limit the flexibility in terms of overall function and component packaging for hybrid vehicles. This study was conducted to determine the feasibility of creating a transmission for hybrid vehicle applications with multiple power inputs/outputs.;The Torque and Speed Control Transmission (TSCT) is a combination of a planetary geartrain and a Continuously Variable Transmission (CVT). By …
Measurement Of Particulate Matter Size, Concentration And Mass Emissions From In-Use Heavy Duty Vehicles, Richard Jason Byers
Measurement Of Particulate Matter Size, Concentration And Mass Emissions From In-Use Heavy Duty Vehicles, Richard Jason Byers
Graduate Theses, Dissertations, and Problem Reports
As technological advancements lower heavy duty vehicle particulate matter (PM) mass emission rates, there is concern that these improvements are increasing the toxicity of the PM by virtue of a subsequent reduction in particle size. These ultrafine particles are able to better penetrate the alveolar region where they can cause serious lung disorders. Alternative fuels such as compressed and liquefied natural gas (CNG and LNG) and the synthetic diesel fuel Mossgas are attractive in that they reduce the levels of total PM. However, use of natural gas in internal combustion engines may produce a larger number of smaller particles than …
Evaluation Of Ceramic Candle Filters Degradation And Damage Location Using Four-Point Bending Tests, Wu Tseng Peng
Evaluation Of Ceramic Candle Filters Degradation And Damage Location Using Four-Point Bending Tests, Wu Tseng Peng
Graduate Theses, Dissertations, and Problem Reports
The structural integrity of ceramic candle filters is a key element for hot gas cleanup systems. Ceramic candle filters used in demonstration plants have experienced degradation and fracturing. Preliminary examination of these ceramic filters indicated that damage of the filters may have resulted from strength degradation due to persistent high temperature operation, thermal transient events, excessive ash accumulation and bridging, and pulse cleaning. This study proposes a nondestructive evaluation of the structural properties of these ceramic filters. The ceramic candle filter is a slender structure made of layers of porous materials. The structure has high acoustic attenuation, which has greatly …
Experimental Characterization Of Heat Transfer From An Electrically Heated Thin Filament, Amy J. Cragg
Experimental Characterization Of Heat Transfer From An Electrically Heated Thin Filament, Amy J. Cragg
Graduate Theses, Dissertations, and Problem Reports
Thin filaments for use in glass, polymer, or textile industries are formed by extruding molten material through an orifice to form a continuous filament. These filaments are cooled rapidly from the melting temperature of the material to near room temperature. If this cooling occurs too rapidly or too slowly imperfections can develop in the filaments. These imperfections can decrease the overall quality and strength of the fiber sometimes leading to temporary production shutdowns caused by filament breakage.;Driven by the need to understand and control the cooling of thin filaments, research has been conducted to attempt to experimentally characterize the heat …
Performance Evaluation Of Exhaust Aftertreatment Devices Used For Emissions Control On Diesel Engines Employed In Underground Coal Mines, Daniel K. Carder
Performance Evaluation Of Exhaust Aftertreatment Devices Used For Emissions Control On Diesel Engines Employed In Underground Coal Mines, Daniel K. Carder
Graduate Theses, Dissertations, and Problem Reports
This study was initiated to assist the WV Diesel Equipment Commission in its promulgation of initial rules, requirements, and standards governing the operation of diesel-powered equipment in underground coal mines. Four different engines and various exhaust after treatment devices that represent current levels of in-use technology were selected for performance evaluation. Both eddy-current and water-brake dynamometers were used to load the engines according to an ISO 8-Mode test cycle. Experimental emissions data, sampled from a full-flow dilution tunnel, suggests that particulate traps can reduce the mass emission rates of particulate matter (DPM) by nearly 90%, while reductions in fuel sulfur …
Characterization Of Particulate Matter And Hydrocarbon Emissions From In-Use Heavy-Duty Diesel Engines, Aleksandar Djordje Bugarski
Characterization Of Particulate Matter And Hydrocarbon Emissions From In-Use Heavy-Duty Diesel Engines, Aleksandar Djordje Bugarski
Graduate Theses, Dissertations, and Problem Reports
A continued increase in the use of diesel engines in heavy-duty vehicles, and the uncertainties about the effects of the emissions on human health have focused attention on risk assessments of exposure to the diesel exhaust. The characterization of diesel particulate matter (PM) and hydrocarbon (HC) emissions is the primary objective toward assessing potential health hazard. The dependence of DPM nature on engine/vehicle operating conditions, fuel type, different after treatment processes, and measurement process on the size resolved PM emissions was examined by operating the test engines and vehicles under steady-state and transient conditions. The regional deposition of DPM in …
Design And Development Of A Microwave-Enhanced Diesel Soot Oxidation System, Bret Allen Rankin
Design And Development Of A Microwave-Enhanced Diesel Soot Oxidation System, Bret Allen Rankin
Graduate Theses, Dissertations, and Problem Reports
Diesel particulate matter (PM) emissions have created considerable concern because PM is a suspected carcinogen. Up to this point, improved engine and fuel system design and control schemes have made the use of diesel particulate aftertreatment systems unnecessary for most applications in the United States, but the continued decreasing trend of emissions regulations may necessitate the use of PM filters for many applications.;Many methods have been developed to generate a controlled, reliable regeneration event within PM filters, none of which have been proven to be completely successful. These methods include exhaust throttling, fuel catalysis, filter catalysis, electrical heating, and burner …
The Effects Of Flow Rate And Sodium Laurel Sulfate Surfactant Concentration On Single- And Two-Phase Heat Transfer Characteristics In A Microchannel, Michael June
Theses
The processing speed of modern microchips and the density of components at the card level has been increasing at a steady rate. With these increases, come an increase in heat generation and a need to dissipate very high heat fluxes. Heat sinks that employ very narrow channels, on the order of 58 - 600um wide have been shown to dissipate heat fluxes as high as 10,000 kW/m2 (Tuckerman, 1984) while maintaining chip temperatures below 130 C. The current study investigates the heat transfer characteristics of single and two-phase flows in a 200 Jim wide channel. Water was used as a …
A Study Of The Stability Of A Hydraulic Actuator System, Paul Stoelting
A Study Of The Stability Of A Hydraulic Actuator System, Paul Stoelting
Theses
One of the least desirable schemes for a linear electro-hydraulic motion control actuator is having a low backup structure stiffness coupled with a high flow gain of the spool valve. It has been demonstrated that this condition causes instability in the form of high frequency oscillations. This thesis examines how actuator parameters can be varied to add stability when a low backup structure stiffness and high flow gain are mandatory design criteria. The stability of the system is examined by developing the system characteristic equation and analyzing its poles in the complex frequency domain. In the complex frequency domain, the …
Measurement Of Residual Stress In Electrodeposited Nickel Films, Gary Richardson
Measurement Of Residual Stress In Electrodeposited Nickel Films, Gary Richardson
Theses
For nearly as long as people have had the ability to create deposits by electrodeposition it has been known that the deposits are made in a state of internal stress. Throughout the past one hundred years several simple techniques used to measure these stresses have been developed. Unfortunately these methods have several shortcomings in both their formulation and interpretation, and seldom have the results from any of these tests been verified by another method. As electroplating becomes utilized to a greater extent in the high-tech applications of aerospace, optics, and electronics it is becoming ever more crucial to gain the …
Optimization Of A Brushless Permanent Magnet Linear Alternator For Use With A Linear Internal Combustion Engine, William Robert Cawthorne
Optimization Of A Brushless Permanent Magnet Linear Alternator For Use With A Linear Internal Combustion Engine, William Robert Cawthorne
Graduate Theses, Dissertations, and Problem Reports
Numerous applications require the generation of electric power without connection to the utility power system. Many industrial, commercial, and personal applications require uninterrupted electrical power in the event of a utility failure. Additionally, the nature of military field operations necessitates the ability to generate electricity in areas where connection to the utility is impractical or impossible. Generation units selected for these applications must be reliable, efficient, compact, and lightweight.;Presently, rotary internal combustion engines coupled with rotary alternators are the primary generation unit used in these applications. This research contends that a tubular brushless permanent magnet linear alternator with a linear …
Unconstrained Instantaneous Center Integration (Ici) Algorithms, Nathan Eggleton
Unconstrained Instantaneous Center Integration (Ici) Algorithms, Nathan Eggleton
Theses
This paper presents several unique "instantaneous center integration" (ICI) algorithms for use in studying unconstrained vehicle motion using computer simulations and animations. Specifically, these algorithms are most appropriate for the case when high angular rates are present, such as would occur during tight cornering and/or possibly during an accident. The three ICI algorithms presented are the "pseudo-exact", first order approximation and the second order approximation. These ICI algorithms are capable of producing valid, accurate, and efficient simulation results, which describe the behavior of a vehicle under these conditions. The "pseudo-exact" is the most accurate, yet the most computationally expensive. The …
The Effect Of Ethylene Glycol Dimethacrylate And Sodium Lauryl Sulfate Surfactants On Droplet Characteristics In Inkjet Printheads, Dawn Api
Theses
The purpose of the present experimental work is to determine the surface tension of various surfactant solutions using the capillary method and observe droplet ejection behavior for these solutions in order to define the correlation between the two. The present work examines the role of surfactants in inkjet printing. One of the most important properties of inkjet ink is surface tension, and surfactants are used in ink to control this property. Specifically studied in this investigation are different concentrations of the surfactants ethylene glycol dimethacrylate and sodium lauryl sulfate. Surfactants have been ejected using a piezo inkjet printhead, and the …
Signiture Analysis Of Fetal Blood Velocity Waveforms, Ronald Soule
Signiture Analysis Of Fetal Blood Velocity Waveforms, Ronald Soule
Theses
Doppler blood velocity waveform analysis is conducted to affect clinical diagnosis. Current analysis codes developed at RIT posses the capability to assess gross hemodynamic parameters such as heart rate, mean pulse velocity, peak systolic velocity and also the beat to beat variability of these parameters. These computer algorithms have, however, lacked the ability to determine hemodynamic indices such as the pulsatility and resistance index as well as the AB ratio. This latter deficiency stems from an algorithmic need to accurately determine end diastolic velocity in every cardiac cycle. The current thesis specifically augments current algorithms to accurately compute end diastolic …
Design Of Anechoic Chamber Instrumentation And Data Acquisition Module For Testing And Analysis Of The Ctha, Srikanth Gururajan
Design Of Anechoic Chamber Instrumentation And Data Acquisition Module For Testing And Analysis Of The Ctha, Srikanth Gururajan
Graduate Theses, Dissertations, and Problem Reports
The backbone of wireless communication is an antenna, a device that converts electromagnetic energy to electric energy and vice versa, to transmit and receive the signals. The effectiveness of a communication system depends largely on the effectiveness of the antenna used in them. The effectiveness of an antenna is characterized by its electromagnetic field. Methods to characterize the field of an antenna include testing them on outdoor test ranges or in enclosures insulated against electromagnetic radiation, called anechoic chambers. The objective of this work is to design and build an automated data acquisition system to map the field of physically …
Compressive Strength Prediction For Composite Unmanned Aerial Vehicles, Edward Albert Wen
Compressive Strength Prediction For Composite Unmanned Aerial Vehicles, Edward Albert Wen
Graduate Theses, Dissertations, and Problem Reports
A rational methodology is presented to predict the compressive strength of carbon/epoxy compression specimens and prototype production parts using the model presented by Barbero in the Journal of Composite Materials, Vol. 32, No.5/1998. The experimental technique is an adaptation of the optical method first proposed by Yurgartis (1987) and can be directly applied to actual development, quality control or failure investigation programs. There is very good agreement between actual and predicted compressive strength at -125F and room temperature. At 180F, the predicted strength is conservative. Aurora Flight Sciences provided the prototype production parts and partial funding under the "Material Characterization …
Simulation Of Packed Column Jigging, Qiang Dai
Simulation Of Packed Column Jigging, Qiang Dai
Graduate Theses, Dissertations, and Problem Reports
Packed column jig has been demonstrated a number of promising results in processing iron ore, coal, chromite and other finely disseminated particulate materials. The packing materials in the jig divide the column into a large number of virtual cells. Each cell performs the similar separation action. A model about the movement of a particle in the packed column jig was derived to interpret the separation mechanism of particles in the virtual cell. A computer program was developed to simulate the particle movement in the jig based on the derived model, which can simulate the packed column jigging with different jig …
Stability Analysis Of Partially Filled Tanker Trucks Using A Finite Element Modeling Approach, Matthew Aquaro
Stability Analysis Of Partially Filled Tanker Trucks Using A Finite Element Modeling Approach, Matthew Aquaro
Graduate Theses, Dissertations, and Problem Reports
The point of rollover for a tanker truck carrying fluid cargo is of great importance due to the catastrophic nature of accidents involving such vehicles. Payloads are often toxic or flammable, thus, predicting the threshold of rollover effectively is of great value. Furthermore, the liquid load shift caused by fluid slosh amplifies the propensity of these vehicles to rollover.;This research presents an approach for determining the threshold of rollover stability of a specific tanker truck by using finite element analysis methods, specifically the software program ANSYS. This approach allows the consideration of many variables which had not been fully considered …
Paramaterized Beams As Effective Human Lip Models, Ron Dufort
Paramaterized Beams As Effective Human Lip Models, Ron Dufort
Theses
There are numerous mathematical equations used by animators and modelers to describe the curves of the human face and, specifically, the human lip. Physically-based polynomial models, b-splines, and other arbitrarily parameterized equations are used to describe facial and lip contours, though with varied degrees of complexity and resolution. This study examined the constraints and conditions necessary to utilize a standard Euler-Bernoulli beam as an effective model for the human lip. Through this analysis it was determined that general beam theories are flexible enough to create models that can generate curves comparable to actual lip shapes, though no single model studied …
Robot Navigation Using Ultrasonic Feedback, Akihiko Baba
Robot Navigation Using Ultrasonic Feedback, Akihiko Baba
Graduate Theses, Dissertations, and Problem Reports
This thesis presents an autonomous navigation program for West Virginia University's mobile robot platform ANT. The program allows the ANT to find a predefined goal by comparing sensor data with a given map of the environment. ANT's ultrasonic sensors were used to sample the surroundings continuously, and this information was combined with dead reckoning data to build a two-dimensional map of the environment. Borenstein's Histogramic In-Motion Mapping technique was used to build sensor maps, which were analyzed to find features such as walls and corners. The features were matched with features in the given map to correct dead reckoning errors. …
Numerical Analysis Of Direct-Chill Casting Of Aluminum Ingot, Yaping Wu
Numerical Analysis Of Direct-Chill Casting Of Aluminum Ingot, Yaping Wu
Graduate Theses, Dissertations, and Problem Reports
Direct chill (DC) semi-continuous casting is the most efficient way to produce large aluminum ingots. This process consists of three main stages; transient stage, steady-state stage, and post-drop stage. During transient stage, the ingot is subjected to rapid cooling rate and thus resulted in the build-up of high thermal stresses that can often lead to ingot cracking failure.;Based on a fully coupled heat-transfer and thermal-stress analysis model, which has been developed using a commercial finite element (FE) package ABAQUS(TM) with a user subroutine developed in-house, the temperature and stress fields were obtained for various casting conditions. Three post-processing programs were …
Head Impact Characterization Of Generic A-Pillar Of An Automobile, Subramani Balasubramanyam
Head Impact Characterization Of Generic A-Pillar Of An Automobile, Subramani Balasubramanyam
Graduate Theses, Dissertations, and Problem Reports
The need to provide enhanced occupant protection for all impact conditions experienced in automobile crashes poses a great challenge. Several safety features such as seatbelts and airbags have been developed to reduce occupant injuries in the event of a crash. However, new studies have indicated that even with these safety features, head impact with the upper interior components have resulted in many injuries leading to fatalities in certain impact conditions such as side collision and rollover. Recent regulations imposed by NHTSA concerning head impact scenarios in automotive crashes are designed to provide maximum head impact protection against several locations on …
Dual Fuel Conversion Of A Direct-Injection Diesel Engine, Talus Park
Dual Fuel Conversion Of A Direct-Injection Diesel Engine, Talus Park
Graduate Theses, Dissertations, and Problem Reports
Dual fuel pilot-injected diesel natural gas engines offer significant potential to reduce oxides of nitrogen (NOx) and particulate matter (PK emissions while maintaining diesel-like efficiency. A 1994 Navistar T444E turbocharger V-8 diesel engine was converted to dual fuel diesel and compressed natural gas (CNG). In an attempt to reduce the overall cost and complexity of conversion, the engine was left completely original, including the diesel fuel injection system. Also, for the sake of simplicity, the method of intake manifold fumigation through an IMPCO, Inc. electronic natural gas control valve was chosen to deliver the CNG. A microprocessor-based electronic control unit …
Design Considerations For Variable Power Split Hydraulic Drives For Industrial Applications, Michael Jan Christian Shellenberger
Design Considerations For Variable Power Split Hydraulic Drives For Industrial Applications, Michael Jan Christian Shellenberger
Graduate Theses, Dissertations, and Problem Reports
Continuously variable transmissions (CVTs) offer some advantages over conventional transmissions in industrial applications. During discrete shifts, conventional transmissions suffer from momentary power transmission lapses, which may produce undesirable effects in the system. Currently, the types of CVTs utilized in industry are hydrostatic drives and hydrodynamic couplings. However, these drives are heavy, presenting an obstacle in applications where weight is a concern. In a power split continuously variable transmission (PS-CVT) the power that flows through the hydraulic element is reduced. This allows the overall size and weight of the transmission to be reduced.;The objective of this thesis is to develop a …
Mean Value Modeling And Control Of A Diesel Engine Using Neural Networks, Yasser Yacoub
Mean Value Modeling And Control Of A Diesel Engine Using Neural Networks, Yasser Yacoub
Graduate Theses, Dissertations, and Problem Reports
Increasingly stringent emissions legislation and demands for improved fuel economy have mandated the need for advanced control algorithms and complicated the diesel engine calibration procedure. To this end, a neural network-based mean value model of a modern turbocharged direct injection diesel engine has been developed and validated. For a pre-specified engine speed schedule and control vector trajectory, the engine model was shown to produce accurate predictions of the turbocharger manifold charging dynamics and combustion efficiency through engine brake torque predictions. The mean value model was coupled with several sub-models to predict exhaust gaseous and particulate emissions and satisfactory predictions were …
In -Cylinder Combustion -Based Virtual Emissions Sensing, Michael L. Traver
In -Cylinder Combustion -Based Virtual Emissions Sensing, Michael L. Traver
Graduate Theses, Dissertations, and Problem Reports
The development of a real-time, on-board measurement of exhaust emissions from heavy-duty engines would offer tremendous advantages in on-board diagnostics and engine control. In the absence of suitable measurement hardware, an alternative approach is the development of software-based predictive approaches. This study demonstrates the feasibility of using in-cylinder pressure-based variables as the inputs to predictive neural networks that are then used to predict engine-out exhaust gas emissions. Specifically, a large steady-state engine operation data matrix provides the necessary information for training a successful predictive network while at the same time eliminating errors produced by the dispersive and time-delay effects of …
Heavy-Duty Emissions Inventory And Prediction, Ravishankar Ramamurthy
Heavy-Duty Emissions Inventory And Prediction, Ravishankar Ramamurthy
Graduate Theses, Dissertations, and Problem Reports
Heavy duty vehicle emissions represent a significant portion of the mobile source emissions inventory. Accurate estimation of their contribution is essential as on-highway and non-road heavy duty diesel emissions account for at least one third of the oxides of nitrogen (NOx) in the inventory. West Virginia University (WVU) has developed an extensive database of continuous transient gaseous emissions levels from a wide variety of heavy duty vehicles in field operation, from which a subset of vehicles (A to J) have been chosen for further analysis. Several different transient cycles were utilized for testing including the Central Business District schedule. The …
A Systematic Study To Investigate The Effect Of Concentration On Flow Boiling Heat Transfer Characterisics In Water Ethylene Glycol System, Murat Bulut
Theses
Mixtures of ethylene glycol and water are employed in cooling engines in automotive applications. To avoid two-phase flow in the engine, the mixture is subcooled in the radiator before entering the engine block. Heat transfer is therefore essentially under subcooled flow boiling conditions. Very little information is available in the literature on the subcooled flow boiling (flow boiling with subcooled liquid) characteristics of this mixture and there are no predictive methods established in this region. In the present investigation heat transfer in the nucleate flow boiling of dilute aqueous binary mixtures was measured and experimental data were compared with available …
Experimental Investigation Of Electromechanical Surface Damping, Rolf Fisher Orsagh
Experimental Investigation Of Electromechanical Surface Damping, Rolf Fisher Orsagh
Theses
Electromechanical Surface Damping (EMSD) is a hybrid technique that incorporates constrained layer damping (CLD) and shunted piezoelectric element methods for the suppression of vibration in light beam-like or plate-like structures. The EMSD technique enhances the damping effectiveness (peak amplitude suppression) at targeted resonant frequencies, and may therefore be used to extend the damping effectiveness of the constrained layer damping technique over a broader temperature and frequency range than CLD alone. This performance enhancement was demonstrated experimentally by comparing the steady state frequency response of cantilever beams that were partially treated with the CLD and EMSD techniques. The experimental results also …
Flow Boiling Heat Transfer Characteristics On Structured Surfaces, Ryan Fogarty
Flow Boiling Heat Transfer Characteristics On Structured Surfaces, Ryan Fogarty
Theses
The present investigation focuses on studying the performance of three specially designed surfaces in flow boiling heat transfer. The surfaces are prepared by drilling holes of specific sizes using laser ablation drilling. The heat transfer characteristics for three laser drilled enhanced surfaces, and a smooth surface are obtained by collecting experimental data for flow boiling of subcooled water over heater surfaces with different matrix of holes. The matrix of laser etched cavities are as follows: Surface 1 9.0um diameter holes spaced at 58.4um Surface 2 - 3.7um diameter holes spaced at 38.6um Surface 3 - 3.7um diameter holes spaced at …