Engineering Science and Materials Commons^™

Design Method Development For The Design Of Traction Systems, Avinash Kolla

All Theses

The objective of this research is to develop a design method for rapid exploration of traction concepts primarily for off-road vehicles. Different approaches available to achieve this objective are discussed and compared, such as computational, analytical, and physical methods. Computational approaches are based on simulations performed using Finite Element Method (FEM), Discrete Element Method (DEM), and combined Finite Element-Discrete Element (FE-DE) methods. Analytical approaches are based on closed form mathematical models developed by previous researchers based on the theory of plasticity. Physical approaches include fabrication and testing of prototypes at different levels of abstraction. This thesis compares these different approaches …

Development Of A Finite Element Model To Predict The Behavior Of A Prototype Wheel On Lunar Soil, Marisa Orr

All Dissertations

The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) is a mobile lunar lander under development by the National Aeronautics and Space Administration's Lunar Architecture Team. While previous lunar missions have lasted only a few days, the ATHLETE is designed to last for 10 years, which will enable a sustained U.S. presence on the moon and exploration of the more treacherous regions which are not suitable for landing. Because the ATHLETE will carry entire astronaut habitats, its six wheels must be carefully designed to support a large load on soft lunar soil efficiently.
The purpose of this thesis is to develop a finite …

Modeling Of Cell Transfer And Process-Induced Cell Damage In Laser-Assisted Cell Direct Writing, Wei Wang

All Dissertations

Laser-assisted cell direct-write technique has been obtaining more and more attention in different biomaterial direct writing applications. A typical laser-assisted cell direct-write process can be divided into two main stages: the cell droplet ejection and cell droplet landing. The objective of this study is to model the cell mechanical profile during the cell droplet ejection and cell landing and further model the cell damage.
The possible cell damage during the droplet ejection process in laser-assisted cell direct writing may come from two different sources: the phase explosion-induced bubble expansion and the thermoelastic stress wave. The bubble expansion-induced stress wave is …

Investigation Of Subgrid-Scale Mixing And Turbulence-Chemistry Interaction In Turbulent Partially Premixed Flames Using Experimental Data, Jian Cai

All Dissertations

The filtered mass density function (FMDF) of mixture fraction, temperature and species used in large eddy simulation (LES) of turbulent combustion is studied experimentally using line images obtained in turbulent partially premixed methane flames (Sandia flames D and E). Cross-stream filtering is employed to obtain the FMDF and other filtered variables. The mean of the FMDF conditional on the subgrid-scale (SGS) scalar variance at a given location are found to vary from unimodal to bimodal, corresponding to quasi-equilibrium distributed reaction zones and laminar flamelets (including extinguished flamelets), respectively. The conditionally filtered mixture fraction dissipation for small SGS variances has a …

Me-Em Enewsbrief, June 2010, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Modeling Of A Porous Metal Foam Cryogenic Counter Flow Heat Exchanger, Craig Fortier

All Theses

This thesis involves the modeling of cryogenic fluids through a porous metal foam counter flow heat exchanger. Although much research has been completed involving light weight high porosity metal foams in recent years, research performed on the subject of mid range porosities in metal foams and their use in heat exchangers has been relatively untouched. Even less literature is available pertaining to the effects of cryogenic fluids in porous metal foams.
Much about heat exchanger performance and pressure drop depends on the structure and relative density of the metal foams. This has been elaborated in several sources, but only for …

Mechanical Milling Of Co-Rich Melt-Spun Sm-Co Alloys, Farhad Reza Golkar-Fard

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Rare-earth, high-energy permanent magnets are currently the best performing permanent magnets used today. The discovery of single domain magnetism in 1950’s ultimately led to the development of nanocomposite magnets which had superior magnetic properties. Previous work has shown that mechanical milling (MM) effectively generates nanoscale structures in Sm-Co-based alloys. MM of more Co-rich, melt-spun Sm-Co alloys (up to the eutectic composition) and the role of initial structure on the milling behavior were investigated.

Sm-Co alloys with compositions of Sm_10.5Co_89.5 and Sm₈Co₉₂ were produced by arc melting, melt-spinning and mechanical milling. X-ray diffraction results showed …

Coupled Dem-Fem For Dynamic Analysis Of Granular Systems In Bending, Kitti Rattanadit

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Characterizing the dynamic behavior of granular materials is one of the great challenges in the mechanics of granular matter. Methods for evaluating the mechanical properties of granular matter have applications in a variety of industries, mining and geotechnical activities, defense and military operations. A coupled 2D Discrete Element Method-Finite Element Method (DEM-FEM) code, called "BobKit", is developed and implemented for analyzing the behavior of a 2D granular layer on top of an elastic beam under deforming (quasi-static) or vibrating (dynamic) of the beam. The explicit time-integration dynamic code is used to simulate quasi-static and dynamic bending of the granular layer …

Re-Engineering A Trash/Recycling Collection Vehicle Based On Challenging Customer Requirements, Edward Smith

All Theses

Engineering design starts with the definition of design requirements. These requirements define the design problem and must be satisfied for a solution to be acceptable. While many design methodologies exist for defining design requirements, none presently provides a systematic approach for designers to challenge requirements. Yet, Pahl and Beitz, Hazelrigg, and Suh all argue that a designer should continually question the need for each requirement and refine them as the product evolves. Thus, there exists a need to develop a comprehensive method that enables a designer to verify, review/question, and revise requirements throughout the design process. This research uses the …

A Proposed Method To Identify Requirements Significant To Mass Reduction, James Mclellan

All Theses

Reducing the mass of engineering products holds the potential for significant benefits by reducing material costs, environmental impact, transportation costs, and in the case of vehicles, reducing fuel consumption. While there are many approaches for reducing mass, analyzing requirements has the greatest potential since requirements definition is the earliest phase of product development, where the most design freedom exists. This thesis proposes a requirement analysis method that identifies requirements that impact significant amounts of mass. The research hypothesis is: Engineering requirements can be represented and processed in a systematic manner and linked to physical components and systems, thus enabling mass …

Electrokinetic Manipulation Of Particles And Cells In Microfluidic Devices, Christopher Church

All Theses

With the recent advancement in micro-fabrication technology, lab-on-a-chip devices have been developed in order to perform biological analysis through cell manipulation. Microchannels used in these lab-on-a-chip devices have been demonstrated to accurately perform many different cell manipulation techniques such as focusing, separation, trapping, and lysis. Although there are many methods available for these techniques, electrokinetics has been rapidly gaining popularity due to the simplicity of application and removal of the need for in channel micro-structures. This thesis studies the use of electrokinetic flow and accompanying phenomena in various structured microchannels to perform focusing, separation, trapping, and lysis of cells. Three …

Interpretability Analysis Of Function Structures At Various Levels Of Abstraction: A User Study, Jonathan Thomas

All Theses

Function models are used during the conceptual design phase of the design process to model the intended use or objective of a product, independent of the products physical form. Function models also aid in guiding design activities such as generating concepts and allocating design team resources. Recent research efforts have focused on the formalization of functional models through a controlled vocabulary and archival of functional representations in computer-based repositories. However, the usefulness and interpretability of these function models has not been rigorously evaluated.
This thesis presents the results of two controlled user studies to ascertain the interpretability of functional representations …

System Modeling And Power Management Strategy For A Series Hydraulic Hybrid Vehicle, Sisay Molla

All Theses

A hydraulic hybrid vehicle draws propulsion power from an internal combustion engine as its prime mover and a gas-charged hydro-pneumatic accumulator as its energy buffer. The accumulator serves the purposes of storing regenerated braking energy and supplementing engine power as determined by an on-board power management strategy. In the configuration known as a series hydraulic hybrid powertrain, the engine is mechanically decoupled from the vehicle's wheels thereby offering excellent opportunities for maximizing energy efficiency and reducing pollutant emissions.
This thesis dealt with the development of a causally interconnected, non-linear, dynamic model of a series hydraulic hybrid powertrain featuring independently controllable …

Comprehensive Analysis Of A Student-Centered Active-Learning Integrated Statics And Dynamics Course For Mechanical Engineers, Marisa Orr

All Theses

The Student-Centered Active Learning in Undergraduate Programs (SCALE-UP) approach to instructional design was adapted with the goal of delivering more effective statics, dynamics and multivariate calculus instruction and integrated course curricula. Inquiry-based learning exercises were designed, incorporating material from statics and dynamics into multivariable calculus, and vice-versa, as well as integrating statics and dynamics into one course. Analysis included an exploration of student study habits, multiple measures of course effectiveness, and an examination of curricular effects. Challenges of implementation are also discussed.
Study habits of students in an integrated Statics and Dynamics course were assessed through a voluntary survey in …

Vehicle Steering Systems - Hardware-In-The-Loop Simulator, Driving Preferences, And Vehicle Intervention, Jesse Black

All Dissertations

The steering system is a critical component of all ground vehicles regardless of their propulsion source. Chassis directional control is provided by the steering system, which in turn relays valuable feedback about the road and vehicle behavior. As the primary feedback channel to the driver, the steering system also delivers the initial perception of a vehicle's handling and responsiveness to the consumer. Consequently, the steering system is an important aspect of the vehicle's evaluation and purchasing process, even if drivers are unaware of its direct influence in their decision making. With automobile purchases potentially hinging on the steering system, a …

Me-Em Enewsbrief, March 2010, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Multiscale Transformation Field Analysis Of Progressive Damage In Fibrous Laminates, Yehia Bahei-El-Din, Ritesh Khire, Prabhat Hajela

Centre for Advanced Materials

As part of an ongoing effort to model uncertainty propagation across multiple scales in fibrous laminates, this paper presents a deterministic transformation field analysis for modeling damage progression under membrane forces and bending moments. In this approach, equivalent eigenstresses are computed in the phases and/or plies such that their respective stress components that satisfy the underlying failure criteria are reduced to zero. Superposition of the solutions found for the undamaged laminate under applied loads and under the eigenstress field provide the entire response. Failure criteria are based on stress averages in the fiber and matrix. Damage mechanisms considered are frictional …

Modified Sandwich Structures For Improved Impact Resistance Of Wind Turbine Blades, Yehia Bahei-El-Din, Mostafa Shazly, I. El-Habbal, Y. Elbahy

Centre for Advanced Materials

Wind turbine blades are susceptible to damage due to fatigue as well as impact by flying objects and parts broken off failed blades of nearby wind towers. Localized, permanent compression of the foam core and delamination of the fibrous composite face sheets are typical damage modes and can lead to progressive structural failure. Sandwich structures modified by inclusion of flexible polyurethane (PU) layers within the cross section are examined under both impact and dynamic loads. Finite element models of sandwich structures with conventional and modified designs show that sandwich designs modified with PU interlayes exhibit reduced foam core crushing and …

Me-Em 2010 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

• First Year to First Career
• Faculty & Staff
• Alumni
• Resources
• Graduates
• Publications

The Characterization Of Leadership Within Undergraduate Engineering Design Teams Through Case Study Analysis, Gary Palmer Ii

All Theses

The purpose of this research is to clearly define leadership that exists within engineering project teams. Leadership can be applicable to any field of study and is heavily researched in business management. Sources which review leadership classify this topic in reference to managerial styles, leadership types and styles, emotional intelligence, and work climate. However, there are few sources which define leadership specifically within engineering environments. The motivation of this research is driven by the absence of defining and observing consistency in engineering leadership through the research‟s experience in engineering teams. Existing leadership is defined in this research through conducting two …

Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha, Florin Bobaru

Department of Engineering Mechanics: Faculty Publications

In this paper we discuss the peridynamic analysis of dynamic crack branching in brittle materials and show results of convergence studies under uniform grid refinement (m-convergence) and under decreasing the peridynamic horizon (δ-convergence). Comparisons with experimentally obtained values are made for the crack-tip propagation speed with three different peridynamic horizons.We also analyze the influence of the particular shape of themicro-modulus function and of different materials (Duran 50 glass and soda-lime glass) on the crack propagation behavior. We show that the peridynamic solution for this problem captures all the main features, observed experimentally, of dynamic crack propagation and branching, as well …

Case Studies: In-Situ Rebuilding Of Damaged Rope Drum Shafts Of Ssg Crane And The Repair Of Circumferential Crack Of Cement Kiln By Welding, Joseph Runyoro

Tanzania Journal of Engineering and Technology (TJET)

Material failures in engineering are characterized by unwanted downtime of equipment and require the application of sound engineering principles to rectify the problem so that it does not reoccur. The most widely method for repairing damaged steel structures such as rope drum shaft or cracked cement kiln is by Manual metal arc welding. The equipment mentioned have their main importance that, when they are broken down, they cost a lot of money in lost revenue and affects a lot of people in terms of business and livelihood. The nominal diameter (DN) 240 rope drum shaft was damaged when the roller …

A Use Of Theory Of Constraints Thinking Processes For Improvements In The Merged Beams Experiment At Oak Ridge National Laboratory., Bryan Richard Gross

Electronic Theses and Dissertations

Thinking exercises used in the Theory of Constraints (TOC) were used to find and remove constraints at the Merged Beams Experiment at Oak Ridge National Laboratory. The goal of this project was to significantly reduce the amount of time used to take a certain type of measurement during an experimental cycle. After the TOC exercises were used, a basic plan for change was discovered. Preliminary data were taken to establish a baseline of performance from which changes were made. Post-Modification was analyzed showing the project was a success.

The overlying reasoning for this exercise was to prove successfully that continuous …

Design, Reconstruction And Evaluation Of A Dynamometer For Quarter Scale, Samuel Sanchez

BioResource and Agricultural Engineering

This project discusses the design, reconstruction, and evaluation of a dynamometer. A new test stand for the Quarter Scale team would improve the testing of the engines and the Continuously Variable Transmission (CVT). All the readings will be done electronically in order to provide the most accurate data collection. The dynamometer will be a closed hydraulic system for ease of use. This system will be able to test all of Quarter Scale engines. The data collected will be used to determine which engines are in the best condition, and which may need to be fixed. With the new design, the …

Vibrations Of Thin Plate With Piezoelectric Actuator: Theory And Experiments, Parikshit Mehta

All Theses

Vibrations of flexible structures have been an important engineering study owing to its both deprecating and complimentary traits. These flexible structures are generally modeled as strings, bars, shafts and beams (one dimensional), membranes and plate (two dimensional) or shell (three dimensional). Structures in many engineering applications, such as building floors, aircraft wings, automobile hoods or pressure vessel end-caps, can be modeled as plates. Undesirable vibrations of any of these engineering structures can lead to catastrophic results. It is important to know the fundamental frequencies of these structures in response to simple or complex excitations or boundary conditions.
After their discovery …

User Study Of Information Extracted From Engineering Representations, Rachel Hannah

All Theses

It is important for designers to understand the usefulness of different engineering representations in order to save time and money throughout a project. Designers often rely on past experience to decide which model to construct; yet students without this experience have no help. Interestingly there are noticeable gaps in the research literature with respect to how and when to select representations and modeling approaches for engineering designs. This thesis examines the differences between three types of engineering representations, specifically sketches, drawing packages, and physical prototypes. The amount of information designers can extract from these representations and also the correctness and …

Modeling The Cooling Phase Of The Lens Molding Process, Saravanan Kannan

All Theses

The lens molding process is a relatively new technique used to manufacture lenses, in particular, high precision aspheric lenses. In order to achieve the desired size and shape of the lens, the cooling process after pressing must be controlled precisely because of the time and temperature dependent viscoelastic behavior of glass near and below the molding temperature. This thesis gives a detailed description of a three-dimensional computational model for analyzing the cooling phase of the lens molding process. Conduction, convection and radiation are considered in the model by coupling a computational fluid dynamics analysis of the flow of nitrogen through …

Robust Parameter Design And Finite Element Analysis For A Non-Pneumatic Tire With Low Vibration, Amarnath Proddaturi

All Theses

During rolling of a non-pneumatic tire, vibration may be produced by the interaction of collapsible spokes with a shear deformable ring as they enter the contact region, buckle and then snap back into a state of tension. Other potential sources of vibration include the interaction of tire tread with the ground and ring vibration. In the present work, a systematic study of the effects of key geometric design parameters is presented using Taguchi's Robust Parameter Design Method and Orthogonal Arrays.
In the present work, a 2D planar finite element model with geometric non-linearity and explicit time-stepping is used to simulate …

Relationships Between Lane Change Performance And Open-Loop Handling Metrics, Robert Powell

All Theses

This work deals with the question of relating open-loop handling metrics to driver-in-the-loop performance (closed-loop). The goal is to allow manufacturers to reduce cost and time associated with vehicle handling development. A vehicle model was built in the CarSim environment using kinematics and compliance, geometrical, and flat track tire data. This model was then compared and validated to testing done at Michelin's Laurens Proving Grounds using open-loop handling metrics. The open-loop tests conducted for model validation were an understeer test and swept sine or random steer test. Four commonly used handling metrics (steady state yaw rate gain, yaw rate damping …

Me-Em Enewsbrief, December 2009, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.