Mechanical Engineering Commons^™

Droplet Behavior In Dense, Low Velocity Aerosols, Alexander Polley

Master's Theses (2009 -)

Rapid compression machines (RCM) are laboratory devices used to measure gas-phase fuel reactivity at conditions relevant to combustion engines. Test mixtures are generally prepared by rapidly compressing a gas phase fuel+oxidizer+diluent mixture to high pressure and temperature (e.g., 10-50 bar, 650-1000 K). It is extremely challenging to utilize diesel-relevant liquid fuels in these devices due to their involatility. One proposed method involves the delivery of an aerosol of suspended fuel droplets (∼ 0.1 mL_fuel/L_gas at stoichiometric fuel loading) to the machine. The compression stroke of the RCM subsequently heats the gas phase of the aerosol thereby achieving …

Heat And Mass Transfer Correlations For Steam Methane Reforming In Non-Adiabatic, Process-Intensified Catalytic Reactors, Adam Stephen Kimmel

Master's Theses (2009 -)

Because of its high energy density, hydrogen is a desirable energy source for the achievement of a renewable energy landscape. Though production methods like thermolysis, electrolysis and biomass conversion, among others, are thought to be long term renewable solutions, catalytic steam methane reforming (SMR) is currently the predominant mechanism to produce hydrogen on an industrial scale. The highly endothermic, transport-limited reforming process has also been scaled down through process intensification to create efficient small-scale hydrogen-generating systems. One proposed geometry utilizes a catalytic finned cylinder that provides a manufacturable solution to enable high-efficiency heat exchange and SMR reaction. An accurate representation …

Surface Preparation Of Naval Ship Construction Steel (Abs-A And Ah-36) Via Bristle Blasting Process, Jorge Andres Martinez

Master's Theses (2009 -)

Bristle blasting is a new and unique corrosion-removal process that is rapidly gaining widespread acceptance among engineers and practitioners in the corrosion/ surface preparation community. Engineers from the ship construction and repair industries face a constant corrosive threat to ships' steel infrastructure and welded joints. To this end, great care is exercised in protecting the vessels' structural integrity and longevity, while maintenance engineers in the ship-building industry seek new methods to improve surface preparation that will not compromise the surface cleanliness and anchor profile required for proper adhesion of paints and coatings.

In this study, the cleanliness and texture of …

Direct Numeric Simulation Of Shock Wave Structures Without The Use Of Artificial Viscosity, Kenneth Bernard Jordan

Dissertations (1934 -)

The purpose of this work is to directly simulate shock wave structures without the use of artificial viscosity. The commonly used artificial viscosity model is replaced with an irreversibility model. Irreversibilities are not typically taken into account when modeling the shock processes because shocks are resolved in a large domain where the thickness of the shock is thin compared to the numeric grid resolution. The result is the shock is poorly resolved. In addition processes other than shock processes are adiabatic and reversible. The result is artificial viscosity, a form of irreversibility, is added to the numeric cells near the …

The Effect Of Cryogenic Treatment On The Fatigue Life Of Chrome Silicon Steel Compression Springs, Debra Lynn Smith

Dissertations (1934 -)

The purpose of this dissertation is to explore the effect of cryogenic treatment on the fatigue life of compression springs. Product manufacturers are constantly searching for ways to make their products last longer. This dissertation addresses three questions: (1) What is the effect of cryogenic treatment on the fatigue life of chrome silicon steel compression springs? Does the life increase, decrease, or remain the same? (2) What is the effect of cryogenic treatment on the Percent Load Loss (Stress Relaxation) of chrome silicon steel compression springs? (3) What are the possible changes in the material that cause these effects?

The …

A Novel Approach To The Part Orientation Problem For Robotic Assembly Applications, Brian James Slaboch

Master's Theses (2009 -)

SCARA (Selective Compliant Assembly Robot Arm) type robots are the most common type of assembly robots. These robots have four degrees of freedom (three rotational and one translational). Typically these robots are used for assembly tasks that take place along a vertical axis. Many times, however, assembly tasks take place along a non-vertical axis. To account for non- vertical axis assembly, parts must be fed in a proper orientation to allow for correct assembly. Parts feeders and specialized end-effectors are typically used to feed parts in their proper orientation. This thesis investigates a novel end-effector that can be used to …

Method Of Tolerance Allocation To Maintain Rotary Balance Of Multi-Component Bodies, Lindsay Louise Rogers

Master's Theses (2009 -)

Vibration of rotating machinery caused by mass imbalance is the most frequent source of unwanted disturbing forces and also the most preventable. In the case of a CT scanner, unwanted vibration in the equipment causes artifacts to the X-ray image, and therefore all measures are taken to eliminate imbalance. The CT scanner is a multi-component rotating body, therefore making it a challenge to account for many discrete components, each with unique variation. This research developed the equations for static and dynamic balance including considerations for inertia. The variation of the components was studied using two models: a sensitivity analysis and …

Optimal Mobile It Location Based On Ergonomics, Kyle Saginus

Master's Theses (2009 -)

U.S. and Canadian electric utility companies are in the process of integrating mobile computers into their fleet vehicle cabs. The placement of the mobile computer in the vehicle cab could have a significant effect on biomechanical loading, performance, and subjective assessment. The objective of this research is to determine the best location to place a mobile computer in a truck cab.

In this experiment, four locations of mobile computers in a truck cab were selected and tested in a laboratory study to determine how location affected muscle activity of the lower back and shoulders; joint angles of the shoulders, elbows, …

One-Dimensional Strain Initiated By Rapid Compaction Of A Heterogenous Granular Mixture Consisting Of Cu, Fe, Sio2, C, Mos2, And Sn, Cullen Braun

Master's Theses (2009 -)

The dynamic compaction of metal powders is of great interest to the metallurgical and military communities. The compaction of a heterogeneous granular mixture consisting of copper, iron, silica, graphite, molybdenum-disulde, and tin predominately used in aviation break-pad creation is presented. The initial density of the material was on average 2.756 g/cm3 . The research also required developing a working projectile velocity measurement system and a proper target assembly for pressure measurements. Manganin gages were used to record the shock wave transit time and the pressure of the transmitted waveform into the powder mixture. An impedance matching technique was utilized to …

Disturbance Attenuation In A Magnetic Levitation System With Acceleration Feedback, Feng Tian, Craig Kevin, Mark L. Nagurka

Mechanical Engineering Faculty Research and Publications

The objective of this work is to demonstrate the use of acceleration feedback to improve the performance of a maglev system, especially in disturbance attenuation. In the single degree-of-freedom (DOF) system studied here, acceleration feedback has the effect of virtually increasing inertia, damping and stiffness. It is shown that it can be used to increase disturbance rejection without sacrificing tracking performance. Both analytical and experimental results demonstrate that disturbance rejection can be improved with acceleration feedback.

The Cd-Te Phase Diagram, Robert F. Brebrick

Mechanical Engineering Faculty Research and Publications

The properties of the liquid phase in the Cd–Te system are fit using thermodynamic properties of CdTe(c) recently optimized by the author. These include a high temperature heat capacity significantly lower than commonly used such that the enthalpy of formation of CdTe(c) at its melting point is about 10 kJ/mol less negative than previously thought. An associated solution model with Cd, CdTe, and Te species is used. Seven adjustable parameters are sufficient to quantitatively fit the liquidus and partial pressures of Te₂ and Cd. Additional partial pressures for Te rich CdTe(c) near its melting point are extracted from an …

A Shovel With A Perforated Blade Reduces Energy Expenditure Required For Digging Wet Clay, Sridhar Harivanam, Richard W. Marklin, Paula E. Papanek, Vikram Cariapa

Mechanical Engineering Faculty Research and Publications

Objective: A shovel with a blade perforated with small holes was tested to see whether a worker would use less whole-body energy to dig wet clay than with a shovel with an opaque blade.

Background: A perforated shovel is hypothesized to require less whole-body energy on the basis of adhesion theory; a smaller surface area would require less physical effort to dig and release soil from the blade.

Method: The study involved 13 workers from an electric utility who dug wet clay with two 1.5-m long-handled point shovels, which differed only in blade design (perforated and opaque). Oxygen consumption was …

Determination Of Cap Model Parameters Using Numerical Optimization Method For Powder Compaction, Cong Lu

Dissertations (1934 -)

Many advantages are inherent to the successful powder metallurgy (P/M) process especially in high volume manufacturing. The strength/density distribution of the compacted product is crucial to overall success. The finite element analysis (FEA) method has become an effective way to numerically simulate strength/density distribution in a P/M compact. The modified Drucker-Prager cap (DPC) model has been shown to be a suitable constitutive relationship for metal powder compaction simulation. The calibration of the modified DPC model involves a procedure known as a triaxial compression test. Equipment for completing a triaxial compression test on metal powders is neither readily available nor standardized …

High Temperature Thermodynamic Data For Cdte (C), Robert F. Brebrick

Mechanical Engineering Faculty Research and Publications

The high temperature heat capacity, Gibbs energy of formation, and standard enthalpy and entropy of formation at 298 K are combined with thermodynamic data for Cd and revised data for Te to provide an internally consistent data set for CdTe(c). Equations are given for the Gibbs energy of formation from Cd(g) and Te₂(g) and from the solid or liquid elements as a function of temperature. These give values similar to those used before. However, the derived enthalpy and entropy of formation are significantly different due to a revised heat capacity for CdTe(c). The standard enthalpy and entropy of …

Multidisciplinary Engineering Systems 2nd And 3rd Year College-Wide Courses, Kevin Craig, Mark L. Nagurka

Mechanical Engineering Faculty Research and Publications

Undergraduate engineering education today is ineffective in preparing students for multidisciplinary system integration and optimization - exactly what is needed by companies to become innovative and gain a competitive advantage in this global economy. While there is some movement in engineering education to change that, this change is not easy, as it involves a cultural change from the silo approach to a holistic approach. The ABET-required senior capstone multidisciplinary design course too often becomes a design-build-test exercise with the emphasis on just getting something done. Students rarely break out of their disciplinary comfort zone and thus fail to experience true …

Reducing Orbit Covariance For Continuous Thrust Spacecraft Transfers, Scott Zimmer, Oscar Ocampo, Robert H. Bishop

Mechanical Engineering Faculty Research and Publications

The calculus of variations is used to develop the necessary theory and derive the optimality conditions for a spacecraft to transfer between a set of initial and final conditions, while minimizing a combination of fuel consumption and a function of the estimation error covariance matrix associated with the spacecraft state. The theory is developed in a general manner that allows for multiple observers, moving observers, covariance associated with an arbitrary frame, a wide variety of observation types, multiple gravity bodies, and uncertainties in the spacecraft equations of motion based on the thrusting status of the engine. A series of example …

Mechatronic Tools For The Modeling And Design Of Servo Motor Actuated Belt Driven Motion Systems, Robert William Copsey

Master's Theses (2009 -)

Mechatronics is defined as the synergistic integration of physical systems, electronics, controls, and computers through the design process, from the very start of the design process, thus enabling complex decision making. This definition reveals the elements involved yet it eludes to the complexity and the constant balance of tradeoffs which are prevalent in the context of applying Mechatronics to a successful design process. This work pursues the use of various tools for the application of Mechatronics to the modeling and design of a servo motor driven motion system.

The use of Mechatronics is pervasive in and among today's highly integrated …

A Fast Nir Spectrometer For Examining Explosive Events: Emission Of Petn Based Explosives And H2O Absorption Method Feasibility, Scott Piecuch

Master's Theses (2009 -)

The chemical dynamics and decomposition pathways of explosive materials are not entirely known. Measurements of chemical transients during explosive events can lead to enhanced knowledge of the detailed chemistry and eventually control of the end products; however, these measurements are often difficult to obtain due to fast time scales and harsh environments. Optical diagnostics present fast-response, minimally invasive methods for resolving properties in detonation environments and previous fast spectroscopic measurements have been recorded in the ultra-violet and visible regions. This work extends the range of such measurements to the near-infrared (NIR) through the development of a fiber-coupled NIR spectrometer utilizing …

The Aerodynamics Of The Knuckleball Pitch: An Experimental Investigation Into The Effects That The Seam And Slow Rotation Have On A Baseball, Michael Patrick Morrissey

Master's Theses (2009 -)

There has been plenty of research on the fluid dynamic effects on different spheres, including sports balls, such as baseballs. Baseball pitches have different velocities, rotation rates and orientations which will cause the baseball to move in different directions. There has also been plenty of research on the aerodynamics of curveballs, but not nearly as much on knuckleballs. The difference between the two is that the knuckleball has a much slower rotation rate and a different initial orientation. This causes the baseball to "knuckle," or moving erratically. This pitch in baseball is one of the hardest to pitch, hit, catch, …

Reconfigurable End Effector Allowing For In-Hand Manipulation Without Finger Gaiting Or Regrasping, Jacob Ames Ziesmer

Master's Theses (2009 -)

The goal of this thesis is to move a step towards the solution of the bin picking problem. A novel metamorphic end effector is proposed, tested for proof of concept and analyzed using standard techniques of degrees of freedom and graph theory as well as a classical dynamic analysis. Once proof of concept was achieved, the results from the analysis were formed into an optimization program with the hope of finding a more stable, predictable mechanism.

Development Of A Velocity Metric For Rigid-Body Planar Motion, Luis Ernesto Criales Escobar

Master's Theses (2009 -)

Two motions of motion quality have been developed for planar motion. They are the "best motion measure" and the "velocity metric". The "best motion measure" identifies the best motion for a given displacement. The "velocity metric" quantifies the discrepancy between two planar motions for the same rigid body.

The best motion measure compares the motion of each particle on the body to an "ideal", but usually unobtainable, motion. This ideal motion moves each particle from its current position to its desired position on a straight-line path. Although the ideal motion is not a valid rigid body motion, this does not …

Mesoscale Behavior Of An Aluminum-Manganese Dioxide-Epoxy Mixture Under Shock Loading: From Milli To Nano-Sized Aluminum Particles, Andrew Fraser

Master's Theses (2009 -)

The main focus of this thesis is to explore the dynamic shock compaction of multiple component mixtures, specifically Al-MnO₂-Epoxy. This will be facilitated by initially simulating the bulk dynamic response in a mesoscale configuration and then comparing these results to experimental data. The mesoscale simulations were performed in the shock code CTH. The first section will discuss the matching of experimental data to computational results. With the goal of determining the bulk shock Hugoniot, a one-dimensional flyer plate configuration was created while using a grain-geometry imported from an scanning electron microscope (SEM) micrograph of the mixture. Both the …

The Effect Of Office Chair Backrest Design On The Body's Metabolic Response To Office Work, Stephen H. Freier

Master's Theses (2009 -)

Most office chairs have a backrest that is wider at the shoulders than at the hips. Recently, a new office chair was developed that has a backrest that is narrower at the shoulders and wider at the hips (upwardly tapered backrest). The upwardly tapered backrest should allow users to increase their ventilatory efficiency, compared to a conventional, wide backrest. This new backrest design will hypothetically allow a user to retract their scapulae, increase expansion of the chest cavity, thus allowing the lungs more space to expand. Specific measures of improved ventilatory efficiency are an increase in tidal volume (V_{t …}

A Mixed-Dimensionality Modeling Approach For Interaction Of Heterogeneous Steam Reforming Reactions And Heat Transfer, Jeroen Valensa

Master's Theses (2009 -)

Hydrogen is most often produced on an industrial scale by catalytic steam methane reforming, an equilibrium-limited, highly endothermic process requiring the substantial addition of heat at elevated temperatures. The extent of reaction, or conversion efficiency, of this process is known to be heat transfer limited. Scaling the industrial process equipment down to the size required for small, compact fuel cell systems has encountered difficulties due to increased heat losses at smaller scales. One promising approach to effectively scale down the reforming process is to coat the catalyst directly onto the heat exchange surfaces of an integrated reactor/heat exchanger. In this …

Development And Implementation Of Novel Bristle Tool For Surface Treatment Of Metallic Components, Piyush Khullar

Master's Theses (2009 -)

Despite advances in paints and coatings technology, protective coatings are prone to eventual corrosion, degradation and/or failure. Consequently, a corrosive layer will develop that can undermine the performance and integrity of structural components. Therefore, both the corrosive layer and defunct coating must be periodically removed, and an acceptable level of surface cleanliness and texture must be obtained prior to the reapplication of new paint. Currently, an array of processes and equipment are used for efficiently cleaning and conditioning metallic surfaces, such as grit blasting, needle guns, and a variety of non-woven and coated abrasive tools.

This research investigates the method …

Inter-Frequency Bias Estimation For The Gps Monitor Station Network, Donny Holaschutz, Robert H. Bishop, R. Benjamin Harris, Brian Tolman

Mechanical Engineering Faculty Research and Publications

The inter-frequency bias (IFB) is present in all dual frequency combinations of GPS pseudorange and carrier phase observables. It is caused by the path dependent signal delays in both the satellite and receiver. That delay can be directly measured for a space vehicle prior to launch, or for a ground based receiver prior to its being used in the field. However the bias is known to drift, and monitoring the delay estimate by direct measurement is time consuming for ground based receivers and impossible for deployed space vehicles. Hansen (2002) examined the observability of IFB through a global model of …

Gender Determination Using Fingerprint Features, Jen-Feng Wang, Chen-Liang Lin, Yung-Hsien Chang, Mark L. Nagurka, Chen-Wen Yen, Chinson Yeh

Mechanical Engineering Faculty Research and Publications

Several previous studies have investigated the gender difference of the fingerprint features. However, regarding to the statistical significance of such differences, inconsistent results have been obtained. To resolve this problem and to develop a method for gender determination, this work proposes and tests three fingertip features for gender determination. Fingerprints were obtained from 115 normal healthy adults comprised of 57 male and 58 female volunteers. All persons were born in Taiwan and were of Han nationality. The age range was18-35 years. The features of this study are ridge count, ridge density, and finger size, all three of which can easily …

A Comparative Study For 2d And 3d Computer-Aided Diagnosis Methods For Solitary Pulmonary Nodules, Chinson Yeh, Jen-Feng Wang, Ming-Ting Wu, Chen-Wen Yen, Mark L. Nagurka, Chen-Liang Lin

Mechanical Engineering Faculty Research and Publications

Many computer-aided diagnosis (CAD) methods, including 2D and 3D approaches, have been proposed for solitary pulmonary nodules (SPNs). However, the detection and diagnosis of SPNs remain challenging in many clinical circumstances. One goal of this work is to investigate the relative diagnostic accuracy of 2D and 3D methods. An additional goal is to develop a two-stage approach that combines the simplicity of 2D and the accuracy of 3D methods. The experimental results show statistically significant differences between the diagnostic accuracy of 2D and 3D methods. The results also show that with a very minor drop in diagnostic performance the two-stage …

Admittance Selection Conditions For Frictionless Force-Guided Assembly Of Polyhedral Parts In Two Single-Point Principal Contacts, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

The admittance of a manipulator can be used to improve robotic assembly. If properly selected, the admittance will regulate a contact force and use it to guide the parts to proper positioning. In previous work, procedures for selecting the appropriate admittance for single principal contact (PC) cases were identified. This paper extends this research for some of the two PC cases-those for which each contact occurs at a single point. The conditions obtained ensure that the motion that results from frictionless contact always instantaneously reduces part misalignment. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reducing conditions …

Mesoscale Calculations Of The Dynamic Behavior Of A Granular Ceramic, John Borg, Tracy J. Vogler

Mechanical Engineering Faculty Research and Publications

Mesoscale calculations have been conducted in order to gain further insight into the dynamic compaction characteristics of granular ceramics. The primary goals of this work are to numerically determine the shock response of granular tungsten carbide and to assess the feasibility of using these results to construct the bulk material Hugoniot. Secondary goals include describing the averaged compaction wave behavior as well as characterizing wave front behavior such as the strain rate versus stress relationship and statistically describing the laterally induced velocity distribution. The mesoscale calculations were able to accurately reproduce the experimentally determined Hugoniot slope but under predicted the …