Engineering Commons^™

Pool Boiling Enhancement Via Micro Ratchets, Lance Austin Brumfield

LSU Master's Theses

Nucleate boiling is an attractive method for achieving high heat flux at low superheat temperatures. It is frequently used for industrial applications such as heat exchangers and is being considered to cool advanced central processing units (CPU) which produce heat fluxes on the order of 1 MW/m2 and are becoming increasing less efficient to cool via forced conduction of air. The issues with implementing nucleate boiling as a cooling mechanism lies in the difficulty of quantifying the complex and numerous mechanisms which control the process. A comprehensive nucleate boiling model has yet to be formulated and will required in order …

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 …

Characterization Of Biocompatible Parylene-C Coating For Biomems Applications, Quoc Phuc Nguyen

LSU Master's Theses

This thesis characterizes parylene-C films with respect to biological micro-electro-mechanical system (BioMEMS) applications. BioMEMS devices have fueled the growth and research in the area of detecting, analyzing and identifying pathogens rapidly with precision in the bio-medical applications, thereby positively impacting millions of lives and made it extremely popular among researchers. These devices are fabricated using state-of-the-art techniques usually involving more than one material which typically has different biocompatibility and is not acceptable for various BioMEMS and biomedical applications; therefore, a special biocompatible coating is required. The parylene polymer is an example of such a coating as it is known for …

Interpretation Of Power Phenomena In Three Phase Systems With Neutral Using Instantaneous Reactive Power P-Q Theory, Rahul Anil Kantharia

LSU Master's Theses

The Instantaneous Reactive power (IRP) p-q theory considered as a major power theory as well as a primary fundamental for switching compensator control in three-phase systems, is analyzed in order to verify its ability to describe and identify the power properties or power phenomena in a 3pN system with asymmetrical and non-sinusoidal voltages along with unbalanced loads. This analysis is an outcome of the misinterpretations of power phenomena in three-wire circuits shown by IRP p-q theory under non-sinusoidal conditions. Different load and supply conditions such as balanced, unbalanced and Harmonic generating loads along with asymmetrical and non-sinusoidal voltages are assumed …

Assymmetry In Distribution Systems: Causes, Harmful Effects And Remedies, Isaac Plummer

LSU Master's Theses

ABSTRACT: Current and voltage asymmetry denigrates the power system performance. The current asymmetry reduces efficiency, productivity and profits at the generation, transmission and distribution of electric energy. Voltage asymmetry reduces efficiency, productivity and profits at the consumption/utilization level. There are a lot of conference and journal papers on the subject of voltage and current asymmetry, however, the information is scattered over a large number of journals and conferences and published over several years. Therefore, the thesis provides a comprehensive compilation of all possible published information on current and voltage asymmetry in the electrical power systems. Published information on sources of …

Long-Term Continuity Moment Assessment In Prestressed Concrete Girder Bridges, Veeravenkata S Murthy Chebole

LSU Master's Theses

Use of new materials, developing new structural systems, and improving construction details while designing bridges with longer spans has been a continuous challenge for bridge engineers since early times. The study of precast/prestressed concrete (PC) bridges made continuous started in early 1960s is one of the most popular alternatives. Continuous structure improves riding comfort and durability of structure, reduction in structural depth, and reserve load capacity under overload conditions. This research presents the state-of-the-art tool for calculating restraint moments in PC continuous bridge girders. The scope of this study is limited to straight slab-on-girder bridges i.e. effects of horizontal curves …

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 …

Power Management And Optimization, Hari Sundararajan

LSU Master's Theses

After many years of focusing on “faster” computers, people have started taking notice of the fact that the race for “speed” has had the unfortunate side effect of increasing the total power consumed, thereby increasing the total cost of ownership of these machines. The heat produced has required expensive cooling facilities. As a result, it is difficult to ignore the growing trend of “Green Computing,” which is defined by San Murugesan as “the study and practice of designing, manufacturing, using, and disposing of computers, servers, and associated subsystems – such as monitors, printers, storage devices, and networking and communication systems …

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 …

Environmental Factors Impacting Coastal Beach Health, Kevin Michael Chenier

LSU Master's Theses

The objectives of this research were to 1) determine the variability of fecal-indicator bacteria in Gulf of Mexico marine waters, 2) determine the effect of environmental variables on enterococci concentrations, 3) determine if beach sand at Holly Beach, LA was capable of acting as a reservoir for fecal-indicator bacteria, and 4) determine if a model could be developed to reduce the time it takes to issue a beach swim advisory. Fecal-indicator bacteria concentrations varied from year to year in historical data collected from a Gulf Coast beach. Afternoon fecal-indicator bacteria concentrations were consistently lower than morning concentrations, demonstrating daily variability. …

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 …

Measurement Of Spatial Variation Of Density Of Compacted Powder Using Synchrotron Microtomography, Yi Yang

LSU Master's Theses

This research considers density change in powder metallurgy when compacting a powder blend in a die. In order to provide insights into particle behavior during compaction, atomized aluminum powders with an average particle size of 100 µm were used in two different compaction configurations. The compaction dies are cylindrical in shape: compaction configuration I displays an upper punch, a die, a lower punch, and a spacer. Compaction configuration II displays an upper punch, two dies, a lower punch, and a spacer with different geometry. The Synchrotron Microtomography scans were conducted on both compaction configurations. For compaction configuration I, the scan …

Parameter Tuning And Experimental Results Of Power System Stabilizer, Bixiang Tang

LSU Master's Theses

Power system stabilizers (PSS) have been studied for many years as a method to increase power system stability. This thesis focuses on the tuning and structure of the power system stabilizer. Different types of power system stabilizers are reviewed. The one studied in this thesis is the integral of accelerated power stabilizer. The generator control system is introduced to illustrate the working environment of the PSS. The mathematic model of the generator, automatic voltage regulator and PSS are analyzed and the system transfer function in presence of the PSS is derived. Base on the transfer function, a new tuning method …

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 …

Design, Fabrication And Characterization Of A New Wind Tunnel Facility – Linear Cascade With A Wake Simulator, Jean-Philippe Junca-Laplace

LSU Master's Theses

A new wind tunnel has been designed and constructed at the LSU Mechanical Engineering Laboratories. The objective was to design a versatile test facility, suitable for a wide range of experimental measurements on turbine blades. The future study will investigate the impact of unsteady inflow conditions on film cooling performance. More specifically, it will study how the unsteady flow due to the upstream passing wakes coming from the front row vane affects the film cooling performances on the turbine blades. The test section consists of a four passage linear cascade composed of three full blades and two shaped wall blades. …

Evaluation Of Simultaneous Water And Gas Injection Using Co2, Shrinidhi Shetty

LSU Master's Theses

Miscible CO2 injection is the second largest contributor to global enhanced oil recovery, as it has successfully undergone extensive laboratory tests and field applications for recovering residual oil left behind after waterflooding. Prolific incremental recoveries have been obtained for some fields. Although miscible CO2 injections generally have excellent microscopic displacement efficiency they often result in poor sweep efficiency. In order to address sweep problems and maximize recoveries, other schemes of gas injection have been developed. Two such processes are water-alternating-gas (WAG) and simultaneous water-and-gas (SWAG) injection. WAG and SWAG have been successfully used to minimize poor sweep. Improved gas utilization …

Building Information Management (Bim) Implementation In Naval Construction, Raymond Rohena

LSU Master's Theses

Traditional two-dimensional (2D) delivery systems in the construction industry can hinder the way information is communicated between owners, architects, and contractors. This hindrance exists in all phases of a project, from design and construction to the operation and maintenance of the completed facility. Building Information Management (BIM) is an emerging information technology that promotes a collaborative process for the Architectural, Engineering, Construction and Facilities Management (AECFM) industry; it can aid the exchange of information and provide improved project data accessibility to all stakeholders of a construction project. The Naval Facilities Engineering Command (NAVFAC), in conjunction with the facility management (FM) …

Pore-Scale Lattice Boltzmann Simulations Of Inertial Flows In Realistic Porous Media: A First Principle Analysis Of The Forchheimer Relationship, Chukwudi Paul Chukwudozie

LSU Master's Theses

With recent advances in the capabilities of high performance computing (HPC) platforms and the relatively simple representation of complex geometries of porous media, lattice Boltzmann method (LBM) has gained popularity as a means of solving fluid flow and transport problems. In this work, LBM was used to obtain flow parameters of porous media, study the behavior of these parameters at varying flow conditions and quantify the effect of roughness on the parameters by relating the volume averaged flow simulation results to Darcy and Forchheimer equations respectively. To validate the method, flow was simulated on regular and random sphere arrays in …

Implementation Of A Wireless Sensor Network With Ez430-Rf2500 Development Tools And Msp430fg4618/F2013 Experimenter Boards From Texas Instruments, Lu De Yang

LSU Master's Theses

Wireless sensor networks have found a great deal of applications in diverse areas. Recent interest has been focused on low-power feature of the sensor nodes because the power consumption is always an issue for wireless sensor nodes which are supplied from the batteries. The eZ430RF2500 Development Tool and MSP430FG4618/F2013 Experimenter Board from Texas Instruments have integrated MSP430 family of ultralow-power microcontrollers and CC2500 low-power wireless RF transceivers which are suitable for low-power, low-cost wireless applications. In this thesis, the features of these TI devices are explored and a wireless sensor network is implemented with these devices. To implement the routing …

Development Of A Total Nutrient Treatment System For Alligator And Dairy Parlor Wastewater Using Hydrated Lime And Organic Bacterial Growth Media, Troy Francis Davis

LSU Master's Theses

Over application of phosphorus and the loss of ammonia-nitrogen to runoff and volatilization have resulted in the buildup of phosphorus in agricultural top soils around the world, and especially in the United States. Over the past few decades, raising livestock has trended towards the development of the Confined Animal Feeding Operations (CAFO’s) which produce large volumes of wastes that need to be treated before being land applied. Nutrient treatment systems have typically focused on one nutrient singularly: either nitrogen or phosphorus. In order to develop a total nutrient system a phosphorus and nitrogen system had to be developed and evaluated …

Lqg/Ltr Control Of Induction Motor, Girish Arvind Yajurvedi

LSU Master's Theses

Induction motors are the most rugged electrical equipment which are widely used in the industry. Owing to the non-linearity in its behaviour, it is not a trivial problem to solve and hence we are interested in using it as a control platform. Through several decades of research a wide number of control schemes have been developed for implementing the closed loop control. Based upon the merits and demerits of various schemes we choose a control scheme called the indirect vector control of Induction motor. Using the electrical dynamics of the motor model we design a LQG/LTR controller. We employ a …

Design, Development, And Testing Of A Multi-Agent Autonomous Surface Fleet For Environmental Applications, Daniel Davis Smith

LSU Master's Theses

As costs have decreased and both computational complexity and robustness have increased, the use of autonomous vehicles in real-world environments has increased dramatically. The development of a fleet of autonomous surface vehicles able to coordinate their actions through communications provides a significant tool for numerous water-based applications such as the reduction of predatory birds on aquaculture ponds, tracking of pollutant gradients, and water quality mapping applications. A fleet of three autonomous surface vehicles (ASVs) was developed using the best characteristics from earlier designs. Each vehicle is a dual-pontoon, dual-paddlewheel design powered by batteries recharged using a vehicle-mounted solar array that …

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 …

Surface Parameterization Over Regular Domains, Shenghua Wan

LSU Master's Theses

Surface parameterization has been widely studied and it has been playing a critical role in many geometric processing tasks in graphics, computer-aided design, visualization, vision, physical simulation and etc. Regular domains, such as polycubes, are favored due to their structural regularity and geometric simplicity. This thesis focuses on studying the surface parameterization over regular domains, i.e. polycubes, and develops effective computation algorithms. Firstly, the motivation for surface parameterization and polycube mapping is introduced. Secondly, we briefly review existing surface parameterization techniques, especially for extensively studied parameterization algorithms for topological disk surfaces and parameterizations over regular domains for closed surfaces. Then …

Modeling Of First-Flush Reactor For Stormwater Treatment, Shaowei Sun

LSU Master's Theses

Stormwater runoff is one of the most common sources of non-point source water pollution to lakes, rivers and estuaries. Nitrate-nitrogen in stormwater runoff is an important limiting factor to the eutrophication phenomenon. While most pollutants and nutrients, including nitrate-nitrogen, in stormwater are discharged into receiving waters during the first-flush period, no existing Best Management Practices (BMPs) are specifically designed to capture and treat the first-flush portion of urban stormwater runoff. In addition, nitrate-nitrogen removal rates of most existing BMPs are relatively low. This thesis presents results from both laboratory experiments and numerical modeling of nitrate-nitrogen removal in a designed first-flush …

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 …

Blind Yield Detection In Steel Structure For Automatic Nondestructive Testing Using Ultrasonic Sensors, Hongting Zhang

LSU Master's Theses

Detection of yield zones using nondestructive testing (NDT) technology for assessing the structural integrity of the existing steel buildings/bridges is extremely important. The average energy over the “effective echoes” (in “good” signal quality) is a robust feature for the yield detection in steel structures. Nevertheless, this average-energy feature extraction requires rigorous manual data-acquisition and human operation. Therefore, in this thesis, we make the first-ever attempt to design a totally-blind and automatic steel-structure yielddetection mechanism, which requires neither the a priori information about the signal nor the human effort in calibration, operation, or data analysis. This new scheme is built upon …

Evaluation Of Volumetric And Mechanistic Properties Of Asphalt Mixtures: Laboratory Vs. Field, Samuel Booth Cooper Iii

LSU Master's Theses

The maintenance and growth of the United States infrastructure is vital to the economic, social, and cultural success of the country. For this reason significant resources must be allocated to ensure adequate paving mixtures are designed, produced, and constructed. A critical issue that has received considerable attention in recent years is to identify and quantify causes, sources, and levels of variability in volumetric and mechanical properties of the mixture. This requires evaluation of three possible scenarios for production of asphalt mixture specimens: (1) laboratory mixed and laboratory compacted specimens (LL), (2) plant mixed and laboratory compacted specimens (PL), and (3) …

Implementing Lean In Healthcare Warehouse Operations - Evaluation Of 5s Best Practice, Sanjith Venkateswaran

LSU Master's Theses

Lean strategies in healthcare aim at improving patient throughput, reducing medication errors, redesigning work flow, improving patient safety, and reducing cycle time. Documented studies to improve healthcare’s warehouse operation are not common in the literature. Managing types of medical supplies has always been a priority due to demand uncertainties and the risk of shortages that would profoundly affect patient safety. This study showcases two implementation approaches for the Lean tool 5S (Hybrid and Traditional) conducted in three different hospitals’ central warehouses at Ochsner Health System. These warehouses store similar medical products with over 1000 types of supplies (e.g. syringes, gloves, …

The Effect Of Exopolymers On The Compressibility And Shear Strength Of Kaolinite, Rick Alton Nugent

LSU Doctoral Dissertations

Erosion and subsidence threaten coastal infrastructure and natural habitats throughout the coastal United States, and this threat is especially significant along the Louisiana coastline since wetland clays are generally weak and highly compressible. Hydraulic pumping of dredged sediment is a common method for combating damage caused by erosion and subsidence, but the high water content slurry deposited is very compressible with low shear strength. Although conventional soil amendments are effective for reducing compressibility and increasing shear strength, these stabilizers are often caustic or toxic, making them too risky to use. Exopolymers, however, have the potential to improve sediment stability without …