Engineering Commons^™

The Worst Case Discharge Scenario, Noah Mcgill

Honors Theses

No abstract provided.

Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer

LSU Master's Theses

Gas turbine blade tips experience very high thermal loads due to high temperature combustion gases and tip leakage flows. This leads to the tip region being very susceptible to experiencing failures. To better understand these effects, experiments were performed in a suction-type low speed wind tunnel cascade to determine heat transfer coefficients and film cooling effectiveness distributions on a highly-loaded 2-D gas turbine blade model in the tip and near-tip regions. The blade shape was generated to match the pressure coefficients of the operating turbine blade design. The model featured multiple tip and pressure side film cooling holes and a …

V2o5-Wo3 Composite Films And Surface-Coated Licoo2 For Enhanced Li-Ion Intercalation Properties, Chuan Cai

LSU Master's Theses

We have investigated the enhanced Li-ion intercalation properties of two different materials, which are V2O5-WO3 composite and surface-coated LiCoO2. A simple and novel solution processing method is employed to prepare V2O5-WO3 composite films that demonstrate enhanced Li-ion intercalation properties for applications in Li-ion batteries or electrochromic displays. This solution processing method employs precursors that only contain the elements of V, W, O and H, which avoids impurity elements such as Na that has been commonly used in other solution methods (e.g. using precursors of sodium metavanadate and sodium tungstate solution). The V2O5-WO3 composite films show enhanced Li-ion intercalation properties compared …

Analytical Design Method For Cold Production Of Heavy Oil With Bottom Water Using Bilateral Sink Wells, Wenting Qin

LSU Doctoral Dissertations

Few heavy oil reservoirs with strong bottom water drives have been developed successfully because of severe water coning. Water coning tends to cause low ultimate recovery, low well productivity, and high water production. Although thermal and gravity-assisted methods might improve recovery in oil reservoirs, such methods are widely perceived as either economically unfavorable or technologically infeasible. This study proposes a new, cold production technique, called Bilateral Water Sink (BWS), to meet those challenges. The BWS method suppresses water cresting by producing oil and water simultaneously from separate, horizontal wells completed in the oil and water zones; the oil and water …

Damage Detection And Identification In Fiber Reinforced Plastic Structural Members And Field Bridges Using Acoustic Emission Technique, Archana Nair

LSU Doctoral Dissertations

With the increased use of fiber reinforced polymer (FRP) based structural systems for rehabilitation of existing and construction of new bridges there is a requirement for identification of critical components of these structural systems and the determination of critical damage thresholds in them. Of the many available non-destructive techniques (NDT), acoustic emission (AE) monitoring had been identified as one of the most popular techniques applicable for damage discrimination in composites. The current study aimed at using patterns in AE data for the identification of damage modes exhibited by composite structural systems. The extensive experimental program involved testing of two structural …

Foldable Substrates For Micro-Ultrasonic Transducers, Karthik Balasubramanian

LSU Master's Theses

Ultrasound has broad range of applications from underwater examination, nondestructive testing of materials and medical diagnosis and treatment. The ultrasonic transducer plays an vital role in determining the resolution, sensitivity, as well as other diagnostic capabilities of an ultrasonic imaging system. Current piezoelectric transducer which dominates the medical field has limited applications compared to the capacitive ultrasonic transducer. The capacitive transducer is easy to fabricate compared to the piezoelectric transducer. In this work, the fabrication of a foldable substrate for a capacitive ultrasonic transducer has been discussed. The foldable substrate was fabricated using an ultrathin silicon wafer which is 50 …

Communication-Constrained Feedback Stability And Multi-Agent System Consensusability In Networked Control Systems, Laurentiu Dan Marinovici

LSU Doctoral Dissertations

With the advances in wireless communication, the topic of Networked Control Systems (NCSs) has become an interesting research subject. Moreover, the advantages they offer convinced companies to implement and use data networks for remote industrial control and process automation. Data networks prove to be very efficient for controlling distributed systems, which would otherwise require complex wiring connections on large or inaccessible areas. In addition, they are easier to maintain and more cost efficient. Unfortunately, stability and performance control is always going to be affected by network and communication issues, such as band-limited channels, quantization errors, sampling, delays, packet dropouts or …

Embedded Piezoelectric Fiber Composite Sensors For Applications In Composite Structures, Hari Prasad Konka

LSU Doctoral Dissertations

Health monitoring of the composite structures is an important issue that must be addressed. Embedded sensors could be an effective way to monitor the health of composite structures continuously and which could also avoid the catastrophic failures of composite structures. Piezoelectric-fiber-composite sensors (PFCS) made from micro-sized Lead Zirconate Titanate (PZT) fibers have great advantages over the traditional bulk PZT sensors for embedded sensor applications. PFCS as an embedded sensor will be an ideal choice to continuously monitor the stress/strain levels and health conditions of composites. This work presents a critical study on using PFCS as an effective embedded sensor within …

A Biomimic Self-Healing Shape Memory Polymer Based Syntactic Foam For Smart Structural Composites, Jones Nji

LSU Doctoral Dissertations

This study explored the development of a new self-healing Polystyrene Shape Memory Polymer (PSMP) based syntactic foam for service life extension in structural polymeric composites. The objective was to self-heal structural-length scale damage in an autonomous, efficient, timely and repeatable manner at the molecular-length scale. Self-healing is achieved through a novel two step close-then-heal (CTH) self-healing scheme, designed to mimic the natural biological process of wound healing in humans. A new methodology to fabricate three-dimensional (3-D) fiber reinforced shape memory polymer syntactic foam for structural applications was developed. The effect of impact energy on the ability for the 3-D fiber …

Discrete Element Modeling Of Cone Penetration In Jsc-1a Lunar Regolith Simulant, Mehmet Burak Cil

LSU Master's Theses

NASA plans to return back to the Moon for a long term presence and use of the Moon as a launch station for further space exploration to other planets. This scenario increases the importance of determining the geotechnical properties of the lunar surface. However, due to the limited availability of lunar regolith and its high scientific value, a simulant material which closely matches the composition and grain size distribution and other characteristics of the lunar regolith has become an indispensable need to benefit in hardware development as well as estimating lunar regolith properties. Therefore, JSC-1A lunar regolith simulant, which was …

Assessing The Suitability Of Various Feedstocks For Biomass Gasification, Akshya Sharma

LSU Master's Theses

Ten different types of feedstocks available in Louisiana were assessed for their suitability to produce SYNGAS in a down-draft biomass gasifier. The feedstocks tested for this research include: pine pellets, hardwood pellets, cypress mulch, pine bark nuggets, corn stover pellets, switchgrass pellets, sugarcane bagasse pellets, dairy manure pellets, and poultry litter pellets. The feedstocks were first analyzed for volatile & ash content, high heating value, moisture, and mass density. Feedstocks that met the analytical criteria and available in a form that is suitable for the down-draft gasifier at LSU were tested for gasification. The temperature profile within the gasifier and …

A Study Of The Scale-Invariant Feature Transform On A Parallel Pipeline, Phaneendra Vinukonda

LSU Master's Theses

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In this thesis we study the running of the Scale Invariant Feature Transform (SIFT) algorithm on a pipelined computational platform. The SIFT algorithm is one of the most widely used methods for image feature extraction.

We develop a tile based template for running SIFT that facilitates the analysis while abstracting away lower-level details. We formalize the computational pipeline and the time to execute any algorithm on it based on the relative times taken by the pipeline stages. In the context of the SIFT algorithm, this reduces the time to that of running the entire image through a …

Solving Evolution Equations For Triad Interaction Of Shallow Water Waves, Qian Zhang

LSU Master's Theses

This study focuses on solving the evolution equations for triad interaction in shallow water waves. First, the evolution equations based on Boussinesq-type equations with Pad¨¦ approximant of the exact linear phase velocity using multi-scale perturbation analysis are derived. Next, methods of solving the complex equation directly, splitting the complex function into amplitude and phase functions, and splitting complex function into real and imaginary parts are implemented to solve the evolution equations. Then the fourth-order Runge-Kutta (RK4) numerical scheme is employed to solve the evolution equations, and corresponding numerical results of three wave interaction are presented demonstrating the sensitivity of the …

Evaluation Of Louisiana Asphalt Pavement Friction, Vivek Lal Das

LSU Master's Theses

This study aims to comprehensively investigate the effect of asphalt mix designs to address skid resistance. The current Louisiana Department of Transportation and Development (LADOTD) specification for friction design considers only the friction rating of aggregate defined by the polished stone value (PSV) obtained by the British pendulum tester (BPT), which is associated with only the micro-texture of asphalt pavement surfaces. The objective of this study is to recommend an asphalt surface friction mix design guideline which is based on both micro- and macro-texture of the wearing course mix. The objective was achieved by evaluating four typical laboratory prepared Louisiana …

Analysis Of Major Hydrologic Events In Ascension Parish, La, Jessica Irene Mason

LSU Master's Theses

Ascension Parish is located in Southern Louisiana and is characterized by low slope and low elevation. This combination allows for much hydrologic storage during a flood event. Because Ascension Parish is one of the most rapidly growing areas in the United States, it is necessary to accurately predict the hydrologic and hydraulic properties of flow and accurately model them. Several processes within a hydrologic model greatly influence the output flow hydrographs so selecting correct methods and parameters is important. Transform methods describe how excess precipitation is transformed into runoff. There are several methods that can be used as a transform …

Comparison Of Different Integral Histogram Based Tracking Algorithms, Sriharsha Atluri

LSU Master's Theses

Object tracking is an important subject in computer vision with a wide range of applications – security and surveillance, motion-based recognition, driver assistance systems, and human-computer interaction. The proliferation of high-powered computers, the availability of high quality and inexpensive video cameras, and the increasing need for automated video analysis have generated a great deal of interest in object tracking algorithms. Tracking is usually performed in the context of high-level applications that require the location and/or shape of the object in every frame. Research is being conducted in the development of object tracking algorithms over decades and a number of approaches …

Supercritical Pyrolysis Of Toluene, Khue Dang Nguyen

LSU Master's Theses

The development of future high-speed aircrafts will required the jet fuel to act as the primary engine coolant to absorb excess heat produced by the engine components. To aid in removing the excess heat and reducing the aircraft’s weight, future jet fuels used for high-speed aircrafts will act as both coolant and fuel; however, by exposing the fuels to temperatures and pressures above their critical point, they undergo pyrolysis to form larger and/or more abundant polycyclic aromatic hydrocarbons (PAH) and eventually carbonaceous solid deposits in the pre-combustion environment. The formation of solid deposits in the pre-combustion environment results in clogging …

Performance Assessment Of Innovative Framing Systems Through Building Information Modeling Based Energy Simulation, Santhosh Reddy Chinnayeluka

LSU Master's Theses

While many residential contractors, architects, and home-buyers today are concerned about the environment and interested in sustainable construction technologies, the perceived higher initial costs of innovative materials and methodologies and a lack of life-cycle cost and performance data present significant barriers in the implementation of such techniques. Research regarding an integrated design process has suggested that performance based decision making is key to the successful implementation of sustainable building practices. Therefore, a need exists for the development of whole building design and evaluation models to allow decision making in all phases of a building project. This research seeks information regarding …

Development And Implementation Of A Dual-Porosity Pore Network Structure Using X-Ray Computed Tomography For Pore Network Modeling Purposes, Samuel Taylor Best

LSU Master's Theses

3-D pore network modeling based on high-resolution X-ray computed tomography (XCT) is a useful tool for simulating pore-scale processes and phenomena within porous media in fields such as chemical and petroleum engineering and groundwater hydrology. XCT images provide the opportunity to capture the true topology of the porous system, retaining important characteristics such as pore geometry, location, and connectivity. However, a major limitation of XCT is its inability to resolve features smaller than the image resolution such as intraparticle porosity and void-space within secondary phases such as clay and micrite, here called microporosity. Identifying this microporosity is important for modeling …

Simulation Of Cell Seeding And Retention In A Disordered Polymeric Scaffold, Tejaswini Narayana

LSU Master's Theses

Historically, bone repair has been performed using materials like metals, ceramics, cements and bioactive glass. The major problem with all these materials is that they do not perform the necessary non-structural functions of bone. Engineered tissue, created by growing bone cells on porous biodegradable material (scaffold), will address this issue with current bone repair techniques. Improving engineered tissue treatments requires a thorough understanding of factors affecting cell seeding and proliferation inside a disordered porous material which is not feasible using current experimental techniques. A model for particle transport in a disordered porous material that can predict the particle deposition pattern …

Hydrodynamic Focusing Micropump Module With Pdms/Nickel-Particle Composite Diaphragms For Microfluidic Systems, Jeonghwan Kim

LSU Master's Theses

In this research, a rapid prototype of multi-fluidic speed-modulating (MFSM) micropump which enables modulation of hydrodynamic focusing in micro-fluidic flow has been designed, fabricated, and characterized. The size of the entire module is 33 mm x 25 mm x 8 mm and comprises of three MFSM micropumps to achieve hydrodynamic focusing. These pumps are simultaneously operated by the same actuation source. Each micropump consists of Tesla-type valves in the bottom layer and PDMS/Ni-particle composite (PNPC) diaphragm in the middle layer. The deflection of the diaphragm is obtained by the external pneumatic force, and the permanent magnet controls the displacement resulting …

Electrochemical Etching Of Isolated Structures In P-Type Silicon, Joel Nino Bugayong

LSU Master's Theses

The role of the space charge region (SCR) was demonstrated in isolated structures for the first time. Electrochemical etching was conducted in differently pitched structures in p-type silicon. A design of experiment was also performed to evaluate the effect of electrolyte and applied potential. Finally chemical etching was demonstrated as a possible post-etch clean to porous structures. The results showed that the morphology of etched structures in pre-patterned silicon is strongly influenced by the SCR even in isolated structures. Using lightly-doped p-type Si (1,000-10,000 Ω-cm), deep macropores were obtained in wide-pitched patterns. However, the diameter of the pores grew larger …

In-Wheel Motors: Express Comparative Method For Pmbl Motors, Pavani Gottipati

LSU Doctoral Dissertations

One of the challenges facing the electric vehicle industry today is the selection and design of a suitable in-wheel motor. Permanent Magnet Brushless (PMBL) motor is a good choice for the in-wheel motor because of its lossless excitation, improved efficiency, reduced weight and low maintenance. The PMBL motors can be further classified as Axial-Flux Twin-Rotor (AFTR) and Radial-Flux Twin-Rotor (RFTR) machines.

The objective of this dissertation is to develop a fast method for the selection of appropriate in-wheel motor depending on wheel size. To achieve this, torque equations are developed for a conventional single-rotor cylindrical, twin-rotor axial-flux and twin-rotor radial-flux …

Small Footprint High Flow Rate Microdevice For Rare Target Cell Capture, Taehyun Park

LSU Doctoral Dissertations

A novel high flow rate cell capture design was introduced to overcome the limitations of the current technologies or methods for rare target cell capture. Even though the rare target cell capture using BioMEMS technology has great potential for cancer diagnosis, previous rare cell capture research could not overcome the limitations of low flow rate or low recovery rate. Rare cell research requires precise sample preparation for accurate results. A new method of preparation for a single or a precise number of target cell was introduced. Current sample preparation methods which are not suitable for rare cell research, such as …

Wave Forces On Bridge Decks And Damping Techniques To Reduce Damages, Aaron Michael Henry

LSU Master's Theses

The population of the Gulf Coast has grown immensely since 1960. Bridges along the coast are a vital part of this area’s infrastructure. They impact the transportation of goods and services, as well as the tourism in these areas. Many of these coastal bridges are at risk of being damaged or even destroyed during extreme weather events. This can cause not only short and long-term monetary problems, but the damage also can exacerbate the issues in getting people out of dangerous areas and getting help into areas in need, after an event. Damages during extreme weather events are the result …

Investigations Of Wave-Induced Turbulent Structures In Vegetated Flows, Agnimitro Chakrabarti

LSU Master's Theses

The role of coastal vegetation in mitigating shoreline erosion by damping of incoming waves and the resultant effect on sediment transport is a critical area of coastal management research. However our understanding of the underlying hydrodynamic processes is limited. Laboratory flume experiments were conducted where a naturally grown emergent vegetation channel and a vegetation-less sand channel were exposed to regular waves. Wave height data was collected using wave gauges located at various points along the channel in the direction of oncoming waves. Acoustic Doppler Velocimeters (ADVs) placed at various depths in the water column measured wave orbital velocity signatures. This …

The Stereospecific Hydrogenation And Dehydrogenation Of Rosin And Fatty Acids, Edward O'Brien

LSU Master's Theses

Tall oil is a byproduct of the standard wood pulping process in the paper industry. It is primarily made up of C:18 fatty acids, rosin acids and a minor fraction of neutrals. Normally, tall oil is further distilled into fractions and then hydrogenated or dehydrogenated into different products. In this project, three heterogeneous catalytic methods of producing byproducts of various distilled tall oil fractions were examined at lower temperatures and pressures than the industry norm in an attempt to develop cheaper production processes. Reactions were conducted in stirred batch reactors of different sizes and product compositions were analyzed primarily by …

Droplet Motion On Miniaturized Ratchets, Jeong Tae Ok

LSU Doctoral Dissertations

The main objective of this study is to evaluate the feasibility of using miniaturized asymmetric structures to move liquid droplets and understand the driving mechanism. We developed the fabrication process for large area topological ratchets with the period ranging from millimeter down to sub-micrometer using micromachining techniques. Non-wetting superhydrophobic surfaces were successfully fabricated using soft UV or thermal nanoimprint lithography, reactive ion etching by oxygen plasma, and chemical surface modification by fluorinated silane vapor deposition. An accurate and reproducible experimental setup equipped with high speed camera and automatic injection system was established. Image processing tools allowed us to obtain various …

On The Thermodynamics Of Degradation, Mehdi Amir Darehbidi

LSU Doctoral Dissertations

All materials when subjected to fatigue loading are prone to failure if the number of cycles exceeds a certain level. Prediction of the number of cycles to failure is, therefore, of utmost importance in nearly all engineering applications. The existing methods for evaluating the fatigue life are tedious, expensive, and extremely time consuming as fatigue often takes many thousands to millions of cycles until failure occurs. Therefore, methods that can readily estimate the number of cycles to failure are highly desirable. In this work, innovative solutions to fatigue problems are presented and their practical significance is discussed. The premise of …

Bio-Implantable Microdevices And Structures For Functional Electrical Stimulation Applications, Naga Srinivas Korivi

LSU Doctoral Dissertations

This dissertation describes the development of microstructures and devices for applications in functional electrical stimulation. A nerve cuff electrode design has been developed for applications in neural electrical stimulation and recording, which addresses limitations with existing cuff electrodes. The developed clip-on micro-cuff electrode design consists of a naturally closed cuff with inner diameter in the micro-scale or above. A novel pinch-hinge feature allows a user to easily open the cuff and place it on target nerve tissue for stimulation or recording purposes. Upon release of the pinch-hinge, the cuff assumes its normally closed nature. The device conducts and reads electrical …