Mechanical Engineering Commons^™

Development Of High Efficiency Dry Powder Inhalers For Use With Spray Dried Formulations, Dale Farkas

Theses and Dissertations

Dry powder inhalers (DPIs) are advantageous for delivering medication to the lungs for the treatment of respiratory diseases because of the stability of the powders, relative low cost, synchronization of inhalation and dose delivery, and many design options that can be used for optimization. However, currently marketed DPIs are very inefficient in delivering medications to the lungs. This study has developed multiple new high efficiency DPIs for use with spray dried excipient enhanced growth (EEG) powder formulations based on the following platforms: capsule-based for oral inhalation, high-dose for oral inhalation, inline with 3D rod array dispersion, and inline with capillary …

3d Cfd Investigation Of Low Pressure Turbine Aerodynamics, Jacob Andrew Sharpe

Browse all Theses and Dissertations

A 3-D Reynolds-Averaged Navier Stokes (RANS) model of a highly-loaded blade profile has been developed using a commercial CFD code with an unstructured/structured grid and several different turbulence models. The ability of each model to predict total pressure loss performance is examined in terms of the spanwise loss distribution and the integrated total pressure loss coefficient. The flowfield predicted by each model is investigated through comparisons of isosurfaces of Q criterion to previous Implicit Large Eddy Simulation (ILES) results. The 3-equation k-kl-¿ model was shown to provide the most accurate performance predictions for a baseline 3-D LPT geometry, and was …

Low-Velocity Impact Behavior Of Sandwich Panels With 3d Printed Polymer Core Structures, Andrew Joseph Turner

Browse all Theses and Dissertations

Sandwich panel structures are widely used in aerospace, marine, and automotive applications because of their high flexural stiffness, strength-to-weight ratio, good vibration damping, and low through-thickness thermal conductivity. These structures consist of solid face sheets and low-density cellular core structures, which are often based upon honeycomb topologies. The recent progress of additive manufacturing (AM) (popularly known as 3D printing) processes has allowed lattice configurations to be designed with improved thermal-mechanical properties. The aim of this work is to design and print lattice truss structures (LTS) keeping in mind the flexible nature of AM. Several 3D printed core structures were created …

Resilience And Toughness Behavior Of 3d-Printed Polymer Lattice Structures: Testing And Modeling, Mohammed Al Rifaie

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This research focuses on the energy absorption capability of additively manufactured or 3D printed polymer lattice structures of different configurations. The Body Centered Cubic (BCC) lattice structure is currently being investigated by researchers for energy absorption applications. For this thesis, the BCC structure is modified by adding vertical bars in different arrangements to create three additional configurations. Four designs or sets of the lattice structure are selected for comparison including BCC, BCC with vertical bars added to all nodes (BCCV), BCC with vertical bars added to alternate nodes (BCCA), and BCC with gradient arrangements of vertical bars (BCCG). Both experimental …

A Numerical And Experimental Investigation Of Steady-State And Transient Melt Pool Dimensions In Additive Manufacturing Of Invar 36, Chigozie Nwachukwu Obidigbo

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The use of additive manufacturing (AM) in tooling enables low production components to be fabricated with lower costs, reduced waste, increased design flexibility and reduced lead time. Invar 36 is a popular metal tooling material known for its low coefficient of thermal expansion. This work uses thermal finite element (FE) modeling as a tool to determine the feasibility of using Invar 36 in AM and to investigate the transient effect from common scanning strategies. Results show that the steady-state melt pool dimensions behave similar to traditional AM materials for varying process parameters. Transient results show that the melt pool response …

Modeling Two Phase Flow Heat Exchangers For Next Generation Aircraft, Hayder Hasan Jaafar Al-Sarraf

Browse all Theses and Dissertations

Two-phase heat exchangers offer the potential of significant energy transfer by taking advantage of the latent heat of vaporization as the working fluid changes phase. Unfortunately, the flow physics of the phase change process is very complex and there are significant gaps in the fundamental knowledge of how several key parameters are affected by the phase change process. Therefore, an initial investigation modeling a two-phase flow heat exchanger has been accomplished. Many key assumptions have been defined which are critical to modeling two-phase flows. This research lays an initial foundation on which further investigations can build upon. Two-phase heat exchangers …

Turboelectric Distributed Propulsion System For Nasa Next Generation Aircraft, Hashim H. Abada

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Next generation aircraft, more specifically NASA aircraft concepts, will include new technologies and make many advancements in fuel economy and noise. However, there are some challenges associated with the latest technologies that NASA is planning to use for the next generation aircraft. For example, these aircraft concepts require large amounts of electrical power to generate the required thrust throughout a notional flight profile. One of the new technologies is using advanced propulsion systems, such as the Turboelectric Distributed Propulsion (TeDP) system, which is significantly different from current aerospace high bypass turbofan based propulsion system. The TeDP propulsion system replaces the …

An Automated Controller Design Methodology For Six Degree-Of-Freedom Aircraft Models, Dominic J. Dierker

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This thesis presents an automated design methodology for development of six degree-of-freedom aircraft controllers. The essential functions required of the controller design are 1) to provide sufficient inner loop compensation to guarantee dynamic stability and acceptable handling qualities over the full flight envelope, and, 2) to enable automated mission following capabilities through implementation of outer loop trackers. A hierarchical control architecture consisting of nested nonlinear dynamic inversion control loops is proposed as a means of achieving these top level objectives. Gain tuning based on an automated linearization methodology is then suggested. Next, an automated optimal control allocation algorithm is tested …

Electrical Power And Storage For Nasa Next Generation Aircraft, Saif Al-Agele

Browse all Theses and Dissertations

Next generation aircraft will incorporate more electrical power generation and storage for both a distributed electric propulsion system and onboard subsystems. The power generation in this type of aircraft will require orders of magnitude higher than today’s commercial aircrafts, thus producing many challenges. For this reason, a unique, high-powered electric propulsion system primarily powered by a turbo-generator system with electrical storage is being considered. A Simulink/Matlab model has bee created for the electrical power system of the next generation blended wing commercial aircraft proposed by NASA. The components of the electrical system include turbo-generators, generators, battery banks, and electrical distribution …

Improving Sensitivity Of Electrochemical Sensors With Convective Transport In Free-Standing, Carbon Nanotube Structures, Benjamin J. Brownlee, Kevin M. Marr, Jonathan C. Claussen, Brian D. Iverson

Faculty Publications

High-aspect-ratio, porous membrane of vertically-aligned carbon nanotubes (CNTs) were developed through a templated microfabrication approach for electrochemical sensing. Nanostructured platinum (Pt) catalyst was deposited onto the CNTs with a facile, electroless deposition method, resulting in a Pt-nanowire-coated, CNT sensor (PN-CNT). Convection mass transfer enhancement was shown to improve PN-CNT sensor performance in the non-enzymatic, amperometric sensing of hydrogen peroxide (H₂O₂). In particular, convective enhancement was achieved through the use of high surface area to fluid volume structures and concentration boundary layer confinement in a channel. Stir speed and sensor orientation especially influenced the measured current in …

Heat Transfer Analysis In A Paddle Reactor For Biomass Fast Pyrolyis, Ankith Ullal

Dissertations, Master's Theses and Master's Reports

Heat transfer analysis was performed on a novel auger reactor for biomass fast pyrolysis. As part of this analysis, correlations for specific heat capacity and heat transfer coefficients for biomass (sawdust) and sand (used as heat transfer medium) were developed. For sand, the heat transfer coefficient followed a power law distribution with reactor fill level and temperature. For raw biomass, the heat transfer coefficient also showed similar dependence on fill level, but was independent of temperature up to 300°C. These correlations were used in a one dimensional heat transfer model developed to calculate the heating time and heating rate of …

A 3d Fem Comparative Study On The Impact Response Between Human Head And Nocsae Head Due To Free Fall, Amey S. Badhe

Dissertations, Master's Theses and Master's Reports

We all enjoy sports be it watching or playing. Concussion is well known topic when it comes sports related injuries. However, concussion and brain injury is not exclusive to sports and outdoor activities. Sometimes, even the impact due to slip and fall at small heights can cause serious damage to the head and brain. This report studies the response generated in the human head model and the commercially use dummy NOCSAE headform due to drop from height of 2, 3, 4 and 5 feet. Earlier studies have related brain kinetics and head kinematics to concussion and traumatic brain injury (TBI). …

Investigation Of The Use Of 3-D Printer Platform As Building Block For Rapid Design Of Research And Manufacturing Tool, Handy Chandra

Dissertations, Master's Theses and Master's Reports

This thesis attempts to show how an open source 3-D printer platform, the self replicating rapid prototype (RepRap), could be used to accelerate the development of research and manufacturing tools. Two projects are shown as examples, both utilizing components of the 3-D printer platform.

The first project is to develop an instrument capable of performing automated large-area four-point probe measurements. A modified RepRap 3-D Printer with a four-point probe in place of the 3-D printer head is utilized as a precision positioning platform. The printer together with custom designed measurement circuit and software performs automated measurement on multiple points on …

Incorporation Of Higher Carbon Number Alcohols In Gasoline Blends For Application In Spark-Ignition Engines, Kristina Lawyer

Dissertations, Master's Theses and Master's Reports

The 2007 U.S. Renewable Fuel Standard (RFS2) requires an increase in the use of advanced biofuels up to 36 billion gallons by 2022. Higher carbon number alcohols, in addition to cellulosic ethanol and synthetic biofuels, could be used to meet this demand while adhering to the RFS2 corn-based ethanol limitation. Alcohols of carbon numbers 2 through 8 are chosen based on their chemical and engine-related properties.

Blend comparison metrics are developed from automotive industry trends, consumer expectations, U.S. fuel legislation, and engine requirements. The metrics are then used to create scenarios by which to compare higher alcohol fuel blends to …

Impact Of E20 Fuel On A High-Performance, Two-Stroke Engine, Jon Gregory Loesche

Dissertations, Master's Theses and Master's Reports

The purpose of this project was to explore the emissions, combustion, and performance effects of running a gasoline/ethanol fuel mixture of 20 percent by volume (E20) in a fuel-injected, two-stroke engine. The engine was operated at five engine speeds that corresponded with the EPA 5-mode emissions test for snowmobile engines. Single parameter sweeps were conducted along with a preliminary recalibration of the test engine at two E0 target values (lambda and mid-pipe temperature) using E20 fuel.

Baseline testing showed that running E20 fuel produced a leaner air/fuel mixture compared to E0, resulting in higher lambda values for all modes and …

Minimizing Run Time Of Finite Element Analyses: Applications In Conformable Cng Tank Modeling, Paul M. Roehm

Dissertations, Master's Theses and Master's Reports

REL Inc. has proposed a CNG tank that deviates from typical cylindrical storage methods. The goal of REL working with Michigan Tech is to minimize mass and meet NGV2 safety standards for pressure and drop testing for this tank.

The model has undulated outer surfaces and Schwarz P-surface internal geometry. To accurately mesh this, a small element size is necessary; this creates a model with millions of elements. In explicit analyses, this requires a large amount of computational resources to run.

This report focuses on methods to reduce model run time without reducing accuracy. Methods covered include creating symmetric building …

Model-Based Control Of Hybrid Electric Powertrains Integrated With Low Temperature Combustion Engines, Ali Soloukmofrad

Dissertations, Master's Theses and Master's Reports

Powertrain electrification including hybridizing advanced combustion engines is a viable cost-effective solution to improve fuel economy of vehicles. This will provide opportunity for narrow-range high-efficiency combustion regimes to be able to operate and consequently improve vehicle’s fuel conversion efficiency, compared to conventional hybrid electric vehicles (HEV)s. Low temperature combustion (LTC) engines offer the highest peak brake thermal efficiency reported in literature, but these engines have narrow operating range. In addition, LTC engines have ultra-low soot and nitrogen oxides (NOx) emissions, compared to conventional compression ignition and spark ignition (SI) engines. This dissertation concentrates on integrating the LTC engines (i) in …

Development Of A High-Fidelity Model And Kalman Filter Based State Estimator For Simulation And Control Of Nox Reduction Performance Of A Scr Catalyst On A Dpf, Venkata Rajesh Chundru

Dissertations, Master's Theses and Master's Reports

Reduction of emissions and improving the fuel consumption are two prime research areas in Diesel engine development. The present after-treatment systems being used for emissions control include diesel oxidation catalyst (DOC) for NO, HC and CO oxidation along with catalyzed particulate filters for PM (particulate matter) and selective catalytic reduction (SCR) for controlling NOx emissions. Recently an after-treatment system called SCR catalyst on a DPF capable of simultaneously reducing both NOx and PM emissions has been developed in order to reduce the overall size of the after-treatment system.

The goal of this proposed research is to create a state estimator …

Simulation Study On Effect Of Gas Charging And Egr In A Dual-Fuel Engine, Satyavenkata Naga Sai Sharath Gorthy

Dissertations, Master's Theses and Master's Reports

Natural gas combined with diesel as micro pilot has the capabilities of achieving lower NOx and soot emissions. Optimization of the combustion process in engines with natural gas and diesel micro-pilot is essential to achieve higher efficiencies and loads. Gas charging (intake air boosting) and EGR are two technologies which when implemented in the natural gas-diesel engines, provide the opportunity to achieve higher efficiencies and loads and low emissions. Simulation study is one of the approaches to investigate the extent and effects of gas charging and EGR on the performance of the engine. With the rapid improvements over the past …

Human Centered Design Of An Open-Drum, Treadle Thresher For Quinoa Farmers In The Andes Of Northern Peru, Robert A. Hayes

Dissertations, Master's Theses and Master's Reports

Growing international demand for quinoa in recent years has led to increased production throughout its South American range, including the Peruvian Andes. Small-scale farmers, who are among the poorest Peruvians, are increasingly growing quinoa for both food security and economic benefit; however, manual harvesting activities, such as threshing, are labor-intensive and time-consuming. This report documents the design, construction and operation of prototype quinoa thresher in a rural village in Northern Peru. In addition, an overview of the history and evolutionary approach to design for the developing world is presented. From this overview, a series of criteria is considered for the …

Using Lower Extremity Muscle Activations To Estimate Human Ankle Impedance In The External-Internal Direction, Lauren N. Knop

Dissertations, Master's Theses and Master's Reports

For millions of people, mobility has been afflicted by lower limb amputation. Lower extremity prostheses have been used to improve the mobility of an amputee; however, they often require additional compensation from other joints and do not allow for natural maneuverability. To improve upon the functionality of ankle-foot prostheses, it is necessary to understand the role of different muscle activations in the modulation of mechanical impedance of a healthy human ankle. This report presents the results of using artificial neural networks (ANN) to determine the functional relationship between lower extremity electromyography (EMG) signals and ankle impedance in the transverse plane. …

The Role Of Active Flow-Control Devices In The Dynamic Aeroelastic Response Of Wind Turbine Rotors, Muraleekrishnan Menon Menon Muraleedharan Nair

Dissertations, Master's Theses and Master's Reports

The significance of wind as a renewable source of power is growing with the increasing capacity of individual utility-scale wind turbines. Contemporary wind turbines are capable of producing up to 8 MW and consequently, their rotor sizes are rapidly growing in size. This has led to an increased emphasis on studies related to improvements and innovations in load-control methodologies. Most often than not, controlling the loads on an operational turbine is a precarious scenario, especially under high wind loading. The up-scaling of turbine rotors would thus benefit from a rationale change in load control through methodologies such as variable-speed stall, …

Multi-Modal And Short-Range Transmission Loss In Ice-Covered, Near-Shore Arctic Waters, Miles B. Penhale

Dissertations, Master's Theses and Master's Reports

In the past century, extensive research has been done regarding the sound propagation in arctic ice sheets. The majority of this research has focused on low frequency propagation over long distances. One of the most commonly used excitation methods for air-ice-water layers has been explosives. However, environmental regulation has become more stringent, disallowing the use of almost all explosive excitation types. Due to changing climate conditions in these environments, new experimentation is warranted to determine sound propagation characteristics in, through, and under thin ice sheets, in shallow water, over short distances. In April, 2016 several experiments were conducted approximately 2 …

Impact Of Natural Gas Direct Injection On Thermal Efficinecy In A Spark Ignition Engine, James Sevik

Dissertations, Master's Theses and Master's Reports

Interest in natural gas as an internal combustion engine fuel has been renewed due to its increasing domestic availability and stable price relative to other petroleum fuel sources. Natural gas, comprised mainly of methane, allows for up to a 25% reduction in engine out CO2 emissions due to a more favorable hydrogen-to-carbon ratio, relative to traditional petroleum sources. Traditional methods of injecting natural gas can lead to poor part-load performance, as well as a power density loss at full load due to air displacement in the intake manifold. Natural gas direct injection, which allows the fuel to be injected directly …

The Emission And Particulate Matter Oxidation Performance Of A Scr Catalyst On A Diesel Particulate Filter With A Downstream Scr, Sagar Sharma

Dissertations, Master's Theses and Master's Reports

Selective catalytic reduction (SCR) systems along with a NH₃ slip control catalyst (ASC) offers NOₓ conversion efficiency >90 % with NH₃ slip < 20 ppm. However, future heavy duty diesel (HDD) engines are designed for higher engine-out NOₓ to improve fuel consumption. Consequently, there is a strong desire to further improve the NOₓ reduction performance of SCR systems, to meet the 2015 California Optional Low NOₓ Standard. SCR catalysts on a diesel particulate filter provide an effective solution to reduce NOₓ and PM using a single aftertreatment device. It also provides an opportunity to increase the SCR volume to achieve NOₓ conversion efficiency >95 %. A downstream SCR catalyst substrate can be used to get additional NO_x conversion by using the SCRF^® outlet NH₃ to increase the cumulative NOₓ conversion of the system.

In this study, NOₓ reduction, NH₃ slip and PM oxidation performance of a Cu-zeolite SCRF^® with a downstream Cu-zeolite SCR were investigated based on engine experimental data at steady state conditions. The experimental data were collected at varying SCRF^® inlet temperatures, space velocities, inlet …

Experimental Investigations Of Temperature Controlled Innovative Annular Flow-Boiling Of Fc-72 In Millimeter Scale Ducts – Steady And Enhanced Pulsatile Realizations, Patcharapol Gorgitrattanagul

Dissertations, Master's Theses and Master's Reports

Steady and steady-in-the-mean shear driven annular flow-boiling is experimentally investigated in this thesis. By annular flow-regime one means separated liquid and vapor flows with the flowing liquid film staying on the boiling-surface.

The goals for the steady annular flow-boiling operations are to better understand relative importance of heat-transfer mechanisms (nucleation versus convective phase-change, with convective meaning absence of nucleation) and to develop better quantitative characterizations/correlations for heat-transfer rates. The goals for the steady-in-the-mean annular investigations was to explore improved means of significantly increasing heat transfer rates - while retaining the flow-regime's annularity.

The experimental investigations (with FC-72 as a working …

Simulation Of Diesel Particulate Filter Regeneration Using Lattice Boltzmann Method, Kshitiz Kumar Jain

Dissertations, Master's Theses and Master's Reports

Lattice Boltzmann Method is a novel approach, which has shown promise in solving a wide variety of fluid flow problems including single and multi-phase flows in complex geometries. Volume elements of the fluid domain are considered to be composed of particles and these particles fall under a velocity distribution function at each grid point. Particles collide with each other under the influence of external forces and the rules of collision are defined so as to be compatible with the Navier-Stokes Equation. In the current work, LBM has been applied to Diesel Particulate filters which is a device used for reducing …

Effect Of Spark Advance And Fuel On Knocking Tendency Of Spark Ignited Engine, Abhay S. Joshi

Dissertations, Master's Theses and Master's Reports

Knock, in spark ignition engine is the combustion caused by the autoignition of the fuel-air mixture. It is the phenomenon that limits engine performance and thermal efficiency. Knock also has an adverse effect on emissions and fuel economy. Engine designers target engines with maximum power and torque output without compromising on fuel economy. Engine downsizing is the method generally adopted. The main goal of engine downsizing is to achieve better fuel economy while increasing the power and torque output of the engine. Better fuel economy is achieved by reducing the displaced volume which in turn means a much higher brake …

Turbulent Transition Simulation And Particulate Capture Modeling With An Incompressible Lattice Boltzmann Method, John R. Murdock

Dissertations, Master's Theses and Master's Reports

Derivation of an unambiguous incompressible form of the lattice Boltzmann equation is pursued in this dissertation. Further, parallelized implementation in developing application areas is researched. In order to achieve a unique incompressible form which clarifies the algorithm implementation, appropriate ansatzes are utilized. Through the Chapman-Enskog expansion, the exact incompressible Navier-Stokes equations are recovered. In initial studies, fundamental 2D and 3D canonical simulations are used to evaluate the validity and application, and test the required boundary condition modifications. Several unique advantages over the standard equation and alternative forms found in literature are found, including faster convergence, greater stability, and higher fidelity …

Fea Analysis And Optimization Of Differential Housing For Fatigue Stresses And Fatigue Test Design To Study Skin Effect In Ductile Iron, Swapnil A. Pandey

Dissertations, Master's Theses and Master's Reports

Automotive emission standards are getting more stringent day by day and governments worldwide are moving to reduce emissions from automobiles. In this scenario reducing the weight of automobile components becomes an important design objective to reduce emissions. A 10% reduction of weight in the complete automobile leads to 6-8 percent improvement in mileage (Mhapankar 2015). Also, powertrain components make up for approximately 27% of the total automobile weight and thus optimizing the design of components in the powertrain is an important task (Mhapankar 2015). Statistics show that 26% of component failures in automobiles are part of powertrain and 21% of …