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2006

Mechanical Engineering

Department of Mechanical and Materials Engineering

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Manipulation Of Polystyrene Microparticles On A Microchannel Glass, Ravi Mamillapalli, Henry D. Young Apr 2006

Manipulation Of Polystyrene Microparticles On A Microchannel Glass, Ravi Mamillapalli, Henry D. Young

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Bulk quantities of spherical microbeads have various applications in research and industrial fields. Simple techniques are required to be developed in order to manipulate and modify large numbers of these beads simultaneously. In our experiment, a microchannel glass-based microfluidic device is used to actuate large numbers of microbeads in parallel. The microchannel glass used in these experiments contains channels 4.1 μm in diameter. The microbeads are polystyrene beads which are superparamagnetic in nature and 5-6 μm in diameter. An aqueous suspension of microbeads is injected into a 2-chamber fluid cell that contains a separator, microchannel glass. The beads are ...


Investigation Into The Behavior Of Bolted Joints, Steven M. Page Jan 2006

Investigation Into The Behavior Of Bolted Joints, Steven M. Page

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Models to capture the physics of jointed structures have been proposed for over 40 years. These models approximate the behavior of the joint under carefully developed operating conditions. When these conditions change, the model has to be changed. Recent developments in numeric codes like finite elements have created interest in incorporating joint models into the design process but joint models need to represent the joined structure over a broader operating range. This work investigates the dynamic response of a structure with a joint. Isolation of a few dominant effects may give way to a model able to capture a broader ...


Using In-Situ Error Tracking For Mode Selection In Proper Orthogonal Decomposition Reduced Order Modelling, Michael Richard Maddux Jan 2006

Using In-Situ Error Tracking For Mode Selection In Proper Orthogonal Decomposition Reduced Order Modelling, Michael Richard Maddux

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Proper Orthogonal Decomposition (POD) provides a method of analyzing data and/or creating a Reduced Order Model (ROM). In this thesis, POD is used to create a ROM comprised of basis functions onto which the governing equations of a Computational Fluid Dynamics (CFD) problem are projected via Galerkin's method. The model is of reduced order since the basis functions span a space smaller than the space from which they were created. A full order simulation called the training period is conducted first to obtain data to be used for creating the ROM using POD. The dominant characteristics are extracted ...


Robust Shape Design Techniques For Steady-State Metal Forming Processes, Jalaja Repalle Jan 2006

Robust Shape Design Techniques For Steady-State Metal Forming Processes, Jalaja Repalle

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Metal forming is a process that transforms a simple shape of a workpiece into a predetermined complex shape through the application of compressive/tensile forces exerted by dies. In the design of a forming process, the only factors that are known are the final component shape and the material with which it is to be made. Then the engineer has to design a process to make defect-free product, subject to limitations of shape, material properties, cost, time, and other such factors. The design cycle can be enhanced if performance sensitivity information is available that could be used with any commercially ...


Computational Study Of Ring-Cusp Magnet Configurations That Provide Maximum Electron Confinement, Taiwo A. Ogunjobi Jan 2006

Computational Study Of Ring-Cusp Magnet Configurations That Provide Maximum Electron Confinement, Taiwo A. Ogunjobi

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Enhancing the confinement of primary electrons within the plasma in a discharge chamber of an ion thruster improves plasma ionization and consequently the thruster's performance. This work computationally calculates the location, position, and orientation of the permanent magnets that provide a ring-cusp magnetic field that maximizes electron confinement in an axi-symmetric cylindrical aluminum-wall discharge chamber. Small samarium cobalt magnets are circumferentially arranged in a ring around the front, side, or back wall of the chamber. The generated ring-cusp magnetic field for any specified magnet configuration is calculated using MAXWELL2D, a two dimensional electromagnetic field simulation computer code. For various ...


Multi-Attribute Optimization Based On Conjoint Analysis, Hemanth K. Amarchinta Jan 2006

Multi-Attribute Optimization Based On Conjoint Analysis, Hemanth K. Amarchinta

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Over the last thirty years, there were tremendous advances in multidisciplinary design optimization in reducing computational cost, developing algorithms for efficient sensitivity analysis in reaching an optimum. Most of these efforts assumed a single objective (attribute) function and a multitude of constraints. Very little work has been done in including the designer's preferences as part of the optimization scheme and in addressing the ability to handle multiple attributes simultaneously. This need to develop a systematic method for including designer's preferences is the main focus of this research work. The concept of modeling preferences among multi-attribute alternatives is prevalent ...