Engineering Commons^™

Thermomechanical Modeling Of Polymerica Actuators, Qianxi Yang

LSU Doctoral Dissertations

In this dissertation, the application of smart polymers as actuators was investigated, with focuses on shape memory polymers and twisted-then-coiled artificial muscles. Thermomechanical models have been developed for various polymeric actuators, so as to facilitate interpretation of the underlying mechanisms and to provide guidance for future design. The classical one-way shape memory effect in amorphous shape memory polymers was first reproduced. The amorphous shape memory polymer was treated as a frozen-phase matrix with active-phase inclusions embedded in it. A phase evolution law was proposed from the physics perspective and the Mori-Tanaka approach was used to predict the effective mechanical properties. …

Careers In Engineering Lesson Plan, Lindsay Snowden

ENERGY Research and Lesson Plans

Careers in Engineering Lesson Plan. The activity is to create a version of a robotic hand with the supplies provided,

Power House Sustainable Energy Education, Rachael Grillo, Molly Hopper, Laura Mills

ENERGY Research and Lesson Plans

No abstract provided.

Research Area 2: Advanced Lightweight And Tailorable Materials, Vlsj Lab, Mechanical Engineering Department, Georgia Southern University

Research Areas

No abstract provided.

Enhanced Dropwise Condensation Via Wettability Contrast Mechanism, Mohammad Alwazzan

Theses and Dissertations

Condensation heat transfer performance can be improved by many methods including the most common used method, which is by increasing the droplet removal rate of the condensing surface. Commonly, this approached can be achieved by promoting a dropwise condensation mode in which super/hydrophobic coatings can be applied on the entire condenser surface to reduce the surface wettability degree. In this dissertation, two main approaches were adapted to enhance the condensation heat transfer performance of the condensing surface via wettability contrast mechanism. Three approaches of investigation were performed to better understand such dropwise condensation promoter methods.

In the first part, alternative …

Experimental And Numerical Investigation Of Pressure Drop In Silicon Carbide Fuel Rod For Application In Pressurized Water Reactors, Ahmed Musafi Abir

Theses and Dissertations

Spacer grids are used in pressurized water reactors (PWRs) fuel assemblies which enhances heat transfer from fuel rods. However, there remain regions of low turbulence in between the spacer grids which contributes to lower heat transfer. To enhance turbulence in these regions surface roughness is applied on the fuel rod walls. Meyer et al [1] used empirical correlations to predict heat transfer and friction factor for artificially roughened fuel rod bundles at high performance light water reactors (LWRs). At present, several types of materials are being used for fuel rod cladding including zircaloy, uranium oxide, etc. But researchers are actively …

Nondestructive Evaluation And Health Monitoring Of Adhesively Bonded Composite Structures, William Walker Roth

Theses and Dissertations

As the growth of fiber reinforced composite materials continues in many industries, structural designers will have to look to new methods of joining components. In order to take full advantage of composite materials, such as increased stiffness, decreased weight, tailored material properties and increased fatigue life, mechanical fasteners will need to be replaced by adhesive bonding or welding, when possible. Mechanical fasteners require the drilling of holes, which damages the laminate and becomes the source of further fatigue damage. Also, an increase in laminate thickness or inclusion of other features is required for the material to withstand the bearing stress …

A Comprehensive Evaluation Of Hybrid Wetting Configurations On Dropwise Condensation, Karim Khazal Egab

Theses and Dissertations

The heat transfer during condensation on a surface depends on the pattern design of the surface, which can highly influence hydrophobic/hydrophilic wettability. In this study hybrid pattern designs were studied. The relationship between the droplet dynamic and the hybrid pattern design can alter the drainage rates, droplet departure frequencies, and the condensation heat transfer rates. Therefore, two series of hybrid patterned surfaces have been designed, developed, and tested during condensation of water vapor on horizontal copper tubes, and compared to complete dropwise and complete filmwise condensation samples. This is to investigate the design that provides the maximum improvement in the …

Research Area 3: Advanced Materials Joining, Vlsj Lab, Mechanical Engineering Department, Georgia Southern University

Research Areas

No abstract provided.

Renewable Energy, Keith Bazemore

ENERGY Research and Lesson Plans

Lesson Plan for Renewable Energy- Environmental Science.

Electroencephalographic Signal Processing And Classification Techniques For Noninvasive Motor Imagery Based Brain Computer Interface, Md Erfanul Alam

Electronic Theses and Dissertations

In motor imagery (MI) based brain-computer interface (BCI), success depends on reliable processing of the noisy, non-linear, and non-stationary brain activity signals for extraction of features and effective classification of MI activity as well as translation to the corresponding intended actions. In this study, signal processing and classification techniques are presented for electroencephalogram (EEG) signals for motor imagery based brain-computer interface. EEG signals have been acquired placing the electrodes following the international 10-20 system. The acquired signals have been pre-processed removing artifacts using empirical mode decomposition (EMD) and two extended versions of EMD, ensemble empirical mode decomposition (EEMD), and multivariate …

Ego-Localization Navigation For Intelligent Vehicles Using 360° Lidar Sensor For Point Cloud Mapping, Tyler Naes

Electronic Theses and Dissertations

With its prospects of reducing vehicular accidents and traffic in highly populated urban areas by taking the human error out of driving, the future in automobiles is leaning towards autonomous navigation using intelligent vehicles. Autonomous navigation via Light Detection And Ranging (LIDAR) provides very accurate localization within a predefined, a priori, point cloud environment that is not possible with Global Positioning System (GPS) and video camera technology. Vehicles may be able to follow paths in the point cloud environment if the baseline paths it must follow are known in that environment by referencing objects detected in the point cloud …

Natural Convection Heat Transfer Of Inclined Sierpinski Carpet Fractal Fins, Luke A. Fussell

Electronic Theses and Dissertations

When designing extended surfaces for the thermal management of electronic devices in aerospace applications it is critically important to minimize mass. However, this can be difficult to achieve as the rate of heat dissipated is directly proportional to the surface area. Fortunately, when certain fractal geometries, like the Sierpinski carpet, are utilized in the design of extended surfaces an increase in surface area and simultaneous decrease in mass can be achieved. The thermal performance of fins inspired by the first four fractal iterations of the Sierpinski carpet pattern was experimentally examined in a natural convection environment. The fractal fins were …

Analytical Solutions And Multiscale Creep Analysis Of Functionally Graded Cylindrical Pressure Vessels, Jasem Amjad Ahmed

LSU Doctoral Dissertations

This study deals with the time-dependent creep analysis of functionally graded thick-cylinders under various thermal and mechanical boundary conditions. Firstly, exact thermoelastic stress, and iterative creep solutions for a heat generating and rotating cylindrical vessel made of functionally graded thermal and mechanical properties are proposed. Equations of equilibrium, compatibility, stress-strain, and strain-displacement relations are solved to obtain closed-form initial stress and strain solutions. It is found that material gradient indices have significant influences on thermoelastic stress profiles. For creep analysis, Norton’s model is incorporated into rate forms of the above-mentioned equations to obtain time-dependent stress and strain results using an …

Fifty-Plus-Year Postflight Analysis Of First Fluid Experiment Aboard A Spacecraft, Mark M. Weislogel, Yongkang Chen, William J. Masica, Fred J. Kohl, Robert D. Green

Mechanical and Materials Engineering Faculty Publications and Presentations

This year marks the 55th anniversary of the first fluid physics experiment performed aboard a spacecraft during the Mercury-Atlas 7 mission. Since then, NASA has conducted over 80 fluids physics experiments aboard a variety of spacecraft, many of which have enhanced the understanding of large-length-scale capillary phenomena relevant to liquid management in the weightless state. As both celebration and demonstration, the Mercury-Atlas 7 fluids experiment is revisited in light of the current understanding of large-length-scale capillary fluidics. Employing a modern numerical tool, a rich variety of experimental outcomes are discovered that were not observed during the flight experiment. Interestingly, experimental …