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LSU Master's Theses

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Full-Text Articles in Mechanical Engineering

Exploration Of Segmented Flow In Microchannels Using The Volume Of Fluid Method In Ansys Fluent, Jace Michael Boudreaux Jan 2015

Exploration Of Segmented Flow In Microchannels Using The Volume Of Fluid Method In Ansys Fluent, Jace Michael Boudreaux

LSU Master's Theses

Segmented flow can be utilized in lab-on-a-chip technologies to speed up chemical and biological analysis. Segmented flow (also known as Taylor flow or the Bretherton problem) has often been explored in circular channels, but rectangular channels are more common for microfluidics applications. To this end, pressure-driven droplet flow in a square microchannel is studied using the volume of fluid method in ANSYS Fluent, a computational fluid dynamics program. It was found that for low Reynolds number (Ret = 0.01) and droplet sizes larger than the channel diameter, the flow is mostly influenced by capillary number and viscosity ratio. The …


Experimental Study Of A Cascade Of Low Pressure Turbine Blades With Upstream Periodic Stator Wakes, Carlos Rene Gonzalez Rodriguez Jan 2015

Experimental Study Of A Cascade Of Low Pressure Turbine Blades With Upstream Periodic Stator Wakes, Carlos Rene Gonzalez Rodriguez

LSU Master's Theses

The objective of this study is to experimentally study film cooling flows. A closed-loop wind tunnel with a four passage linear cascade of US Air Force Research Laboratory (AFRL) ultra-high-lift L1A low pressure turbine (LPT) blades and upstream wake generator is used in conjunction with Particle Image Velocimetry (PIV) flow visualization technique to study turbulent film cooling flows due to the interaction between vanes and blades. Further post-processing in the form of Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) modal analyses is performed to determine the relevant modes that characterize the coherent structures in the flow. An image …


Radiation Heat Transfer In A Particulate Medium Using A Ray Tracing Method, Manish B. Patil Jan 2015

Radiation Heat Transfer In A Particulate Medium Using A Ray Tracing Method, Manish B. Patil

LSU Master's Theses

In the present work, a complete 3D simulation of ray tracing model is developed for studying the radiation heat transfer, associated with laser based additive manufacturing, in both thick and thin particulate beds by using the Monte Carlo method. Additional program is developed for creating different types of packing structures such as simple cubic, rhombohydral and random packing. The scattering mechanisms in the particulate beds for large opaque spheres are evaluated using the specular and diffuse reflection methods. Further, a novel approach has been added to the model to include isotropic, forward and backward scattering mechanisms for a medium which …


Development Of A Three-Dimensional Bioprinter With Inline Light Activation For Bone Tissue Engineering, Colton Alexander Mcelheny Jan 2015

Development Of A Three-Dimensional Bioprinter With Inline Light Activation For Bone Tissue Engineering, Colton Alexander Mcelheny

LSU Master's Theses

Bioprinting offers exciting possibilities for tissue engineering related to tissue and organ failure due to trauma, disease, or aging. This is of substantial societal value as the world populace mean age rises. Current needs for tissue and organ repair far exceed availability. A strategy being explored to counter this imbalance is the single step fabrication of cellular constructs. This paper explores various bioprinting techniques and suggests a custom design for a cost-effective, low-maintenance bioprinting platform for academic research. The platform functionality was validated via two-dimensional image transfer and simple three-dimensional geometries.


A Comparative Assessment Of Ergonomic Risk Factors In University Personnel Using Rula And Reba Aiming To Study The Cause And Effect Relationship, Nabila Chowdhury Jan 2015

A Comparative Assessment Of Ergonomic Risk Factors In University Personnel Using Rula And Reba Aiming To Study The Cause And Effect Relationship, Nabila Chowdhury

LSU Master's Theses

The aim of this research was to conduct an ergonomic assessment of working postures and the design of computer workstations of the employees in Louisiana State University. The purpose of the study was threefold- (1) to determine the major ergonomic issues in university employees while working on computer workstations, (2) to compare the two ergonomic assessment tools (RULA and REBA) to see how similarly or differently they assess the risks present in the same working condition and (3) to develop a model that correlates between working condition, work posture and computer workstation design with their effects on musculoskeletal system. This …


Multiscale Modeling Of Smart Materials Under Static And Dynamic Thermo-Mechanical Loading, Soodabeh Sharafi Jan 2015

Multiscale Modeling Of Smart Materials Under Static And Dynamic Thermo-Mechanical Loading, Soodabeh Sharafi

LSU Master's Theses

Engineering material systems with tailored capabilities are a topic trend in plethora of research. Polymer based Artificial Muscle, PAM, and Shape memory polymer fiber, SMPF, enable structural engineers to incorporate smartness functionality into their design through programming cycles. Smartness functionality leads to the production of artificial muscles with different load carrying capability. SMPF is another category of smart materials, which are capable of being micro-structurally engineered to isolate vibration at different temperature and frequency conditions. The smartness functionality offers the adjustment between inherent properties of these materials with their industrial applications through modeling techniques. Mixture of phenomenological, numerical, mathematical models …


An Analytic Solution Of The Thermal Boundary Layer At The Leading Edge Of A Heated Semi-Infinite Flat Plate Under Forced Uniform Flow, Robert Jessee Jan 2015

An Analytic Solution Of The Thermal Boundary Layer At The Leading Edge Of A Heated Semi-Infinite Flat Plate Under Forced Uniform Flow, Robert Jessee

LSU Master's Theses

Abstract The heated flat plate under uniform flow has been vastly studied, with the Blasius and Pohlhausen solutions developed over 100 years ago. These solutions are numerical in nature. Here, an analytic solution is found for the temperature and velocity profiles at the leading edge of a heated flat plate under forced uniform flow. By defining a similarity variable the governing equations are reduced to a dimensionless equation with an analytic solution at the leading edge. This report gives justification for the similarity variable via scaling analysis, details the process of converting to similarity form, and presents a similarity solution. …


The Effects Of Work Zone Configurations On Physiological And Subjective Workload, Mahmoud Shakouri Hassanabadi Jan 2015

The Effects Of Work Zone Configurations On Physiological And Subjective Workload, Mahmoud Shakouri Hassanabadi

LSU Master's Theses

There is a dearth of research on the effect of driving through work zones on physiological and subjective workload of drivers. The objectives of this research were to (a) study the effect of work zones and traffic density on physiological measures of workload, subjective workload and performance variables (b) study the relationship between physiological measures of workload, subjective workload and performance variables. Conventional lane merge (CLM), joint lane merge (JLM) and a road without a work zone (control) were modeled with high and low traffic density by using a full-size driving simulator. 13 female and 17 male students volunteered to …


Association Of Lean Implementation On Perceived Organizational Maturity Levels Of Managers And Staff In The Public Sector, Patrick Eduardo O'Mara Jan 2014

Association Of Lean Implementation On Perceived Organizational Maturity Levels Of Managers And Staff In The Public Sector, Patrick Eduardo O'Mara

LSU Master's Theses

Extensive research has shown the impact of Lean implementation at the process level of an organization to increase quality, reduce cycle time, and reduce operational costs. However, little research has been done to associate Lean with improvement at the strategic level of an organization. The objectives of the present research were to (a) study the association of Lean implementation with maturity levels of employees (b) study the relationship between Lean implementation in the levels of agreement with cohesion between managers and staff in evaluating perceived current state and desired state of organizational practices (c) identify potential barriers of Lean implementation …


Using A Sleep And Activity Monitor To Operationalize Fatigue Risk Management, Vanessa Bégat Seitz Jan 2014

Using A Sleep And Activity Monitor To Operationalize Fatigue Risk Management, Vanessa Bégat Seitz

LSU Master's Theses

When a person continues to work despite being fatigued, an accident may occur or productivity may decrease. Reducing fatigue related accidents is complicated due to the subjective nature and pervasiveness of the feeling of fatigue. Because finding one universal definition or measure of fatigue is problematic, fatigue is typically measured by a combination of factors such as amount of sleep obtained, physical or cognitive work performed, or sleepiness which can then be related back to a measure of performance. Until recently, sleep measurement was restricted to a lab setting; however, with the emergence of actigraph devices, it is now possible …


Assessing The Effects Of Work Zone Configurations On Drivers' Visual Attention, Karthy Punniaraj Jan 2014

Assessing The Effects Of Work Zone Configurations On Drivers' Visual Attention, Karthy Punniaraj

LSU Master's Theses

This study assessed the effects of two different work zone configurations on driver’s visual attention by eye movement monitoring. A driving simulator study was conducted with thirty participants. Variations in traffic density and warning sign placement distance were added to the merge configurations to simulate the real time situation. A 2 x 2 x 3 within-subjects factorial design was used for this research. The independent variables used in this study were (1) merge configuration [(i) Conventional Lane Merge (CLM) and (ii) Joint Lane Merge (JLM)], (2) traffic density [(i) high and (ii) low] and (3) distance between traffic signs [(i) …


Age, Performance And Retention Interval Effects On Acceptance Of A Consumer Health Information Technology System, Stephen Andrew Ford Jan 2014

Age, Performance And Retention Interval Effects On Acceptance Of A Consumer Health Information Technology System, Stephen Andrew Ford

LSU Master's Theses

The older adult population will continue to place pressure on the financial and resource allocation of the healthcare industry as the over 65 population continues to grow. Health care expenditures to treat the aging population will continue to rise as older adults are more likely to have expensive chronic conditions. The future may lay with Consumer Health Information Technology which may allow the patients to have more control of their treatment schedule and self-management of their health and chronic conditions. However, older adults may exhibit cognitive declines that prohibit the learning and proper use of technology, and this assumption is …


A Parametric Investigation Of A Novel, Modular, Gasketless, Microfluidic Interconnect Using Parallel Superhydrophobic Surfaces, Christopher Ramsey Brown Jan 2014

A Parametric Investigation Of A Novel, Modular, Gasketless, Microfluidic Interconnect Using Parallel Superhydrophobic Surfaces, Christopher Ramsey Brown

LSU Master's Theses

The gasketless microfluidic interconnect has the potential to offer a standardized approach to interconnects between modular microfluidic components. This strategy uses parallel superhydrophobic surfaces (contact angle ≥ 150ᴼ) to passively seal adjacent, concentric, microfluidic ports separated by an air gap using a liquid bridge created between the chips. The parallel superhydrophobic surfaces do not require the addition of a gasket or other additional components so that the assembly process scales favorably with an increasing number of fluidic interconnects. The gasketless seal does not contribute to geometric constraint between the component chips which allows alignment between chips to scale favorably with …


An Experimental Investigation Of Corrosion Fatigue Life Via Thermographic Method, Richard Wayne Purvis Jan 2014

An Experimental Investigation Of Corrosion Fatigue Life Via Thermographic Method, Richard Wayne Purvis

LSU Master's Theses

The effect of prior corrosion fatigue damage on the thermographic response of 1018 low carbon steel is investigated. Specimens were subject to rotating bending fatigue at 38 Hz loading frequency while being exposed to a 3.5% NaCl and distilled water solution. Some specimens were subject to corrosion fatigue for part of their fatigue life and then their thermographic response measured under fatigue in air at 62 Hz loading frequency. Fatigue tests in air with thermographic measurement were performed as a comparison. It was observed that the initial temperature rise after corrosion fatigue fits the previously proposed model for air fatigue, …


A Thermographic Method For Remaining Fatigue Life Prediction Of Welded Joints, Paul Thomas Williams Jan 2014

A Thermographic Method For Remaining Fatigue Life Prediction Of Welded Joints, Paul Thomas Williams

LSU Master's Theses

A non-destructive thermographic technique is adapted and applied to study the fatigue life and behavior of welded specimens made from two different materials. Results show good agreement between experimental predictions of consumed fatigue life and predicted fatigue life. Further, the thermal evolution of the specimens is used to calculate Damage Parameter, which is also used to make fatigue life predictions with promising results. To gain further insight Buckingham Pi theorem is also applied to determine the role of the important parameters involved in a dimensionless form. For this purpose, a series of experiments were performed and used for the analysis …


Fabrication And Enhancement Of Aluminum-Based Microchannel Devices, Paul Joseph Hymel Jan 2014

Fabrication And Enhancement Of Aluminum-Based Microchannel Devices, Paul Joseph Hymel

LSU Master's Theses

Microscale molding replication and transient liquid phase (TLP) bonding were used to fabricate Al-based microchannel heat exchangers (MHEs) and micro gas chromatograph (mGC) columns. Metal-based microchannel heat exchangers often experience corrosion as a result of their operating conditions. To address this problem, an internal anodization method was developed in Al microtubes by pulsing the flow of electrolyte through a microtube when the current dropped below a set value. The anodic aluminum oxide (AAO) films were characterized by scanning electron microscopy (SEM), focused ion beam (FIB) cross sections, and X-ray energy dispersive spectroscopy (EDS) to determine their growth rate and morphology. …


Using Eye-Tracking To Investigate Strategy And Performance Of Expert And Novice Control Room Operators, Christina Marie Koffskey Jan 2014

Using Eye-Tracking To Investigate Strategy And Performance Of Expert And Novice Control Room Operators, Christina Marie Koffskey

LSU Master's Theses

There is lacking research within the Petrochemical Industry that uses eye-tracking to explore the differences between the strategies of expert and novice control room operators as they monitor and address process parameters that could be used to improve novice training programs and interface design. Scan paths and three eye-tracking metrics (Fixation Frequency, Gaze Duration Mean, and Gaze Percentage) were used to investigate the differences in eye behavior of three expert control room operators and six novice students as they monitored and corrected a Crude Refinement simulation. A 2x2x2 mixed factor design was used to explore the effects that expertise (expert …


Minimization Of Transportation, Installation And Maintenance Operations Costs For Offshore Wind Turbines, Tasnim Ibn Faiz Jan 2014

Minimization Of Transportation, Installation And Maintenance Operations Costs For Offshore Wind Turbines, Tasnim Ibn Faiz

LSU Master's Theses

Although it is a sustainable source and there is abundant potential for energy, cost of energy generated from offshore wind is still high compared to other sustainable energy sources. Apart from the manufacturing cost of turbines, cost of energy is significantly affected by costs of transportation and installation operations of wind turbines and maintenance operations of turbine components. Through optimum selection of decision variables, such as turbine installation method and rated power output of each turbine, cost of transportation and installation operations can be minimized. The first model in this study investigates the impact of these decision variables and effect …


Analyses Of Online Monitoring Signals For A Gmaw Process Before And After Improvement, Aniruddha Joshi Jan 2014

Analyses Of Online Monitoring Signals For A Gmaw Process Before And After Improvement, Aniruddha Joshi

LSU Master's Theses

The ability to detect the onset of welding instability is a very powerful tool in welding process monitoring and control. Toward this goal, this study investigates a gas metal arc welding (GMAW) process by analyzing online monitoring signals. Two separate data sets are obtained from the process, which correspond to (a) a stable process after improvement and (b) a relatively unstable process which tends to exhibit spatter and poor weld bead geometry. Voltage, current, wire-feeding speed and line speed signals for both data sets are analysed and features are extracted from the raw signals using different signal processing techniques. Specifically, …


Influence Of Magnetic Fields On The Evaporation And Combustion Of A Single Droplet, Domingo Elias Jan 2014

Influence Of Magnetic Fields On The Evaporation And Combustion Of A Single Droplet, Domingo Elias

LSU Master's Theses

The reliance on combustion as the primary source of energy will continue in the US for the next thirty years [1]. Experiments suggest that the use of magnetic fields can be one tool in the many-sided approach to the problem of environmental protection and energy conservation in the US. For instance, it is estimated that an increase in efficiency of 2% in spray combustion can save the US economy billions of dollars [2]. In this thesis I report on improving the quality of combustion through the use of magnetic fields. (1)I investigated the effects of magnetic fields on the evaporation …


Composition Control Of Spinel Lithium Manganese Oxide For High Voltage, High Energy Lithium Ion Batteries, Hilary Eikhuemelo Jan 2014

Composition Control Of Spinel Lithium Manganese Oxide For High Voltage, High Energy Lithium Ion Batteries, Hilary Eikhuemelo

LSU Master's Theses

In the quest for renewable source of energy, a remarkable step made was in the introduction of the battery system. The lithium ion battery was revolutionary in this regard particularly for its light weight and high energy density. There has been significant progress in the development of this battery system since the present form was introduced in the 1990s. There is currently a global dependence on the use of lithium ion battery in diverse applications such as in the electronics, communications and automobiles. Unfortunately, the energy obtainable from the lithium ion battery continuously falls behind the energy demand. This setback …


Effect Of Rest Time On Heart Rate, Perceived Exertion, And Strength, Amir Bahador Bahmani Bahman Beiglou Jan 2013

Effect Of Rest Time On Heart Rate, Perceived Exertion, And Strength, Amir Bahador Bahmani Bahman Beiglou

LSU Master's Theses

Finding a proper work/rest schedule is considered an important factor for improved efficiency, safety, and a higher rate of productivity in the workplace. The purpose of this study was to determine the optimum rest period for lifting tasks using heart rate, perceived exertion, and physical strength. First, the maximum acceptable weight of the box to be lifted was determined for each one of 10 participants using a psychophysical approach. Then on separate days, participants were required to repetitively lift the box from knuckle height to shoulder height for 20 minutes. They were then allowed to rest 5, 10, 15, or …


Instability Analysis And Suppression Of Instability In Low-Density Gas Jets, Sukanta Bhattacharjee Jan 2013

Instability Analysis And Suppression Of Instability In Low-Density Gas Jets, Sukanta Bhattacharjee

LSU Master's Theses

A numerical study is conducted to understand the global instability of very low-density jets (as encountered in thermal plasmas). The simulations have been carried out for different parameters of density ratios, S = ƒÏj /ƒÏ‡ ranging from 0.5 to 0.03, different Reynolds numbers ranging from 500 to 4000 and different momentum thickness obtained by different extension tube length ranging from 3 to 6 diameter long. The flow parameters and vortex structures has been visualized to understand the details of the evolution of the flow field. The axisymmetric shear layer rolls up in the near field of the jet forming vortex …


Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda Jan 2013

Liposomal Uptake Of Silver And Gold Nanoparticles, Dipon Chanda

LSU Master's Theses

The main objective of this work is to study the liposomal uptake of silver and old nanoparticles. Liposomes were prepared in Heating Method. The phospholipids used to prepare liposomes are 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (16:0 PC); 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (16:0 PG); 1,2-distearoyl-sn-glycero-3-phosphocholine (18:0 PC); 1,2-distearoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (18:0 PG).Four different combinations of phospholipids were used to prepare liposomes. In all four combinations two types of phospholipids were used. The liposomes were incubated for 30 minute, 1 hour, 2 hour and 4 hour with silver and gold nanoparticles in streptavidin coated glass slide. All four liposomal formulations had a biotinylated lipid (1-oleoyl-2-[12-biotinyl(aminododecanoyl)]-sn-glycero-3-phosphocholine) which has a string …


Comprehensive Study Of The Dye Sensitized Solar Cell, Gregory Lewis Vick Jan 2013

Comprehensive Study Of The Dye Sensitized Solar Cell, Gregory Lewis Vick

LSU Master's Theses

A complete electrical model of the dye-sensitized solar cell has been presented. This model relates the material parameters of the cell to the cell’s performance. The full model is reduced to an Idealized form and simulated to find an idealistic power curve or current (I) – voltage (V) curve. The operating parameters of reflectivity, temperature, reverse saturation current and ideality factor are investigated. A sensitivity analysis is completed to determine what parameters have a dominating influence on the overall cell performance. It was found, for the ideal case of the dye sensitized solar cell, that the factors of absorptivity, temperature, …


Parametric Optimization Of A Single-Tracked Vehicle, Darrick Jason Berner Jan 2013

Parametric Optimization Of A Single-Tracked Vehicle, Darrick Jason Berner

LSU Master's Theses

ABSTRACT The purpose of a suspension system for a vehicle is to contribute to the handling and assist in isolating the occupants from vibrations due to road irregularities. Generally, these primary functions are often at odds so the goal is to design a suspension system that finds the appropriate compromise. The focus of this thesis is to develop a two degree of freedom model and use parametric analysis to demonstrate an optimization technique by varying several geometric characteristics on a single-track vehicle. Furthermore, a dynamic vibration absorber will be added to the model to demonstrate its effect on the system. …


Closed Form Solutions To The Optimality Equation Of Minimal Norm Actuation, Jorge Antonio Guerra Jan 2013

Closed Form Solutions To The Optimality Equation Of Minimal Norm Actuation, Jorge Antonio Guerra

LSU Master's Theses

This research focused on the problem of minimal norm actuation in the context of partial natural frequency or pole assignment applied to undamped vibrating systems by state feedback control. The result of the research was the closed form solutions for the minimal norm control input and gain vectors. These closed form solutions should took open loop eigenpairs and the desired frequencies of the controlled system and outputted the optimal controller parameters. This optimization technique ensures that the system’s dynamics will be effectively controlled while keeping the controller effort minimal. The controller must then be able to shift only the desired …


Effects Of Partial Confinement And Local Heating On Healing Efficiencies Of Self-Healing Particulate Composites, Jonah Champagne Jan 2013

Effects Of Partial Confinement And Local Heating On Healing Efficiencies Of Self-Healing Particulate Composites, Jonah Champagne

LSU Master's Theses

Shape memory polymers are smart materials that can be trained to hold a temporary shape through programming and regain their original shape upon heating. Since there discovery in the 1960s, much research has been devoted to the study of these polymers. Of particular interest in recent years is the study of self-healing shape memory polymers. In a previous study, it has been shown that in order for efficient healing to take place in self-healing shape memory polymers, confinement during healing is essential. Moreover, a two-step close-then-heal (CTH) approach to healing was suggested. It was shown that use of this CTH …


Effect Of Surface Roughness On The Efficiency Of Self-Healing Polymers, Ifeanyi Janarus Okoro Jan 2013

Effect Of Surface Roughness On The Efficiency Of Self-Healing Polymers, Ifeanyi Janarus Okoro

LSU Master's Theses

A shape memory polymer (SMP) is a smart material capable of maintaining two distinct shapes depending on its temperature. A SMP is soft at temperatures above its glass transition temperature but hard below it. When copolyester thermoplastic additives are dispersed in a SMP, it becomes a SMP-based particulate composite capable of self-healing at both the molecular level and the structural level. This makes it very desirable for industrial applications. Upon damage to the composite, the surfaces at the damage interface have to come into contact for efficient healing; the shape memory effect, coupled with a confined recovery (healing) process, ensures …


Characterization And Verification Of A Closed Loop Wind Tunnel With A Linear Cascade And Upstream Wake Generator, Christopher Foreman Jan 2013

Characterization And Verification Of A Closed Loop Wind Tunnel With A Linear Cascade And Upstream Wake Generator, Christopher Foreman

LSU Master's Theses

A closed loop wind tunnel designed to study film cooling was completed in May 2011 along with a removable wake generating device. The test section featured a three blade, four passage linear cascade utilizing the Air Force Office of Scientific Research L1A low pressure turbine blade. The wake generator is unique because its blades are flat plates with round leading and trailing edges instead of circular rods. In this report, the test section of the wind tunnel is characterized and validated through velocity and pressure measurements in the test section. Hot-wire surveys were used to characterize the velocity and turbulence …