Engineering Commons^™

Progressive Water-Oil Transition Zone Due To Transverse Mixing Near Wells, Shengkai Duan

LSU Doctoral Dissertations

This study derives from observations made in petroleum research and practices of chemical industry that efficient mixing takes place in segregated immiscible fluid flow in granular packs and static mixers. A hypothesis was formulated that transverse mixing (TM) across oil-water interface may occur in segregated inflow to wells resulting in progressive transition zone, more water production, and reduced oil productivity. “Mixing” is broadly interpreted here to address the entire range of stirring, splitting, dispersion and diffusion processes between two fluids.

Initial study showed that a commercial reservoir simulator would not model any transition zone in segregated oil-water flow at high …

Temperature Impact On Nitrification And Bacterial Growth Kinetics In Acclimating Recirculating Aquaculture Systems Biofilters, Milton Maada-Gomoh Saidu

LSU Doctoral Dissertations

This project assessed short-term temperature effects on total ammonia nitrogen (TAN) utilization rates in a batch laboratory-scale recirculating system. The tank system was designed for experiments on short term steady state and diurnal temperatures. A set of numerical models was developed to simulate observed results. The performance of the biofilters was determined with three tank replicates at fixed temperatures of 13, 20 and 300C; and at diurnal transient (sinusoidal) temperature regimes of (20 ± 30C; 30 ± 30C). Ammonia utilization rates and biofilter performance for beads acclimated at different temperatures regimes separated and mixed were also determined. Total ammonia utilization …

Thermomechanical Characterization Of A Shape Memory Polymer Based Syntactic Foam, Damon Nettles

LSU Master's Theses

Shape memory polymers (SMPs) are a type of smart material capable of “remembering” multiple shapes and transitioning between them in response to an external stimulus. They offer the potential to self-seal macro-length scale damage in a nearly autonomous fashion. Syntactic foams are lightweight structural materials currently used in the marine and aerospace industries. This study seeks to bring syntactic foams and SMPs together, retaining characteristics of both components, to create a low-density smart composite. The SMP based syntactic foam is used as the core of a grid stiffened sandwich structure capable of healing impact damage multiple times. In order to …

Bilateral Filter In Image Processing, Ming Zhang

LSU Master's Theses

The bilateral filter is a nonlinear filter that does spatial averaging without smoothing edges. It has shown to be an effective image denoising technique. It also can be applied to the blocking artifacts reduction. An important issue with the application of the bilateral filter is the selection of the filter parameters, which affect the results significantly. Another research interest of bilateral filter is acceleration of the computation speed. There are three main contributions of this thesis. The first contribution is an empirical study of the optimal bilateral filter parameter selection in image denoising. I propose an extension of the bilateral …

The Development Of A Pore Pressure And Fracture Gradient Prediction Model For The Ewing Banks 910 Area In The Gulf Of Mexico, Jeffrey Steven Fooshee

LSU Master's Theses

The purpose of this project is to develop a pore pressure and fracture gradient prediction strategy for the Ewing Banks 910 (EW 910) area. Petrophysical and measured pressure data for eight wells previously drilled in the EW 910 area will be examined and reviewed. This strategy will help design future drilling and completion operations in the aforementioned area. Two pore pressure prediction strategies and one fracture gradient prediction strategy will be reviewed and applied to the available data. The first pore pressure prediction strategy reviewed was developed by W. R. Matthews. This strategy utilizes a geologic age specific overlay which …

Thermal Characterization Of Plain And Carbon Nanotube Reinforced Syntactic Foams, Pratap Chandrashekhara Bhat

LSU Master's Theses

Syntactic foams are composite materials in which the matrix phase is reinforced with hollow particles called microballoons. They possess properties such as low moisture absorption, low thermal conductivity and high damage tolerance because of their compositions. Traditionally, syntactic foams are used for many high strength applications and as insulating materials. But for applications demanding better heat dissipation from syntactic foam, conductive filler materials need to be added while maintaining its property of low density. Carbon nanotubes although extremely conductive, have issues of agglomeration in the matrix. In this research, a new approach to the problem of dispersion of nanotubes was …

Gas Transfer In Air-Lifts Used To Recirculate Aquaculture Systems, Ryan Anthony Hearn

LSU Master's Theses

The following studies were conducted to determine hydraulic, aeration, and degasification characteristics associated with various air-lift pumps. The first study presented data on a 20.3 cm air-lift used to support adult Yellowtail broodstock (Seriola lalandi) in an oligotrophic warmwater marine RAS (recirculating aquaculture system). Empirical relationships were used to estimate actual oxygen and carbon dioxide mass transfer rates (AOTR & ACTR) as the inlet oxygen or carbon dioxide concentrations were perturbed under lift heights of 30.5, 38.1, and 45.7 cm. Transfer rates, kg of constituent per day, were found to be dependent on air injection depth and volume, aqueous gas …

Quantitative Macro- And Microscale Methods For Characterizing Cell Viability, Julianne Forman Audiffred

LSU Doctoral Dissertations

The goal of this study is to combine molecular and microdevice methods to characterize and quantify viability of single mammalian cells. Fluorescent-based assays were optimized for adherent HeLa and suspension Jurkat cells and were used as a tool for validation of a microfabricated diagnostic device. Cell and substrate/surface interactions were considered for designing a microfluidic device that can be used to characterize cell viability for quantitative biomedical and cell biology applications, which require label-free, real-time monitoring of cells. Several interdisciplinary methods are employed to evaluate electrical impedance differences between live and dead Jurkat cells in a microfluidic device. Biological Micro-Electro-Mechanical …

Scheduling And Reconfiguration Of Interconnection Network Switches, Krishnendu Roy

LSU Doctoral Dissertations

Interconnection networks are important parts of modern computing systems, facilitating communication between a system's components. Switches connecting various nodes of an interconnection network serve to move data in the network. The switch's delay and throughput impact the overall performance of the network and thus the system. Scheduling efficient movement of data through a switch and configuring the switch to realize a schedule are the main themes of this research. We consider various interconnection network switches including (i) crossbar-based switches, (ii) circuit-switched tree switches, and (iii) fat-tree switches. For crossbar-based input-queued switches, a recent result established that logarithmic packet delay is …

Physical Layer Security In Wireless Networks: Intelligent Jamming And Eavesdropping, George Traian Amariucai

LSU Doctoral Dissertations

This work aims at addressing two critical security issues residing in the physical layer of wireless networks, namely intelligent jamming and eavesdropping. In the first two chapters we study the problem of jamming in a fixed-rate transmission system with fading, under the general assumption that the jammer has no knowledge about either the codebook used by the legitimate communication terminals, or the source’s output. Both transmitter and jammer are subject to power constraints which can be enforced over each codeword (peak) or over all codewords (average). All our jamming problems are formulated as zero-sum games, having the probability of outage …

Photocatalytic Reaction In Monolithic Optical Fiber Reactor With Inverse Opal Catalyst, Maoming Ren

LSU Doctoral Dissertations

The development of photocatalytic reactor is essential for the successful application of heterogeneous semiconductor in environmental study, which has been shown to be photoactive and effective to oxidate organic pollutant and photoreduce CO2 to useful compounds. In this dissertation, a monolithic optical fiber reactor (MOFR) coated with inverse opal titania, which uses optical fibers as light-transmitting conductor and support of catalyst, was developed for both photodegradation and photoreduction. 1,2-dichlorobenzene, a volatile organic compound (VOC), was selected as the organic pollutant. This configuration of reactor and catalyst provides a high surface area, enhances mass transfer within the catalyst, manipulates photons transmission …

Fabrication, Bonding, Assembly, And Testing Of Metal-Based Microchannel Devices, Fanghua Mei

LSU Doctoral Dissertations

Microsystem technologies are believed to be an important part of the contemporary technological foundation and are becoming a commercially significant specialty area in manufacturing. The design and fabrication of microscale engineering structures has the potential of generating revolutionary changes in many products over a wide range of industrial sectors. Metal-based microchannel heat exchangers (MHEs) promise high heat transfer coefficients together with mechanical robustness, and are of interest for a wide range of applications. Fabrication technologies capable of creating high-aspect-ratio microscale structures (HARMSs) in metals such as Cu at low cost and high throughput are of particular interest. Likewise, simple and …

Meso-Scale Heating Predictions For Weak Impact Of Granular Energetic Solids, Rohan Panchadhara

LSU Doctoral Dissertations

An explicit, two-dimensional, Lagrangian finite and discrete element technique is formulated and used to computationally characterize meso-scale fluctuations in thermomechanical fields induced by low pressure deformation waves propagating through particulate energetic solids. Emphasis is placed on characterizing the relative importance of plastic and friction work as meso-scale heating mechanisms which may cause bulk ignition of these materials and their dependence on piston speed (vp ~ 50-500 m/s). The numerical technique combines conservation principles with a plane strain, thermoelastic-viscoplastic constitutive theory to describe deformation within the material meso-structure. An energy consistent, penalty based, distributed potential force method, coupled to a penalty …

Pore-Scale Analysis Of Dnapl Dissolution And Biomass Distribution, Keegan L. Roberts

LSU Doctoral Dissertations

A comparison of equilibrium and non-equilibrium dissolution of tetrachloroethylene (PCE) was conducted to ascertain how PCE saturation, individual blob properties (volume, surface area, sphericity), and PCE occupied pores are affected by two distinct dissolution regimes. One-dimensional columns were imaged at various dissolution stages using high resolution (~10 um) synchrotron x-ray tomography (XT) and image subvolumes were analyzed using a series of grain, pore network structure, and blob analysis algorithms. An analysis of algorithm-generated data was conducted to determine grain and pore statistics, PCE saturation and individual blob properties, and correlations between PCE blobs and pore network structure. Grain and pore …

Integrated Data-Driven Techniques For Environmental Pollution Monitoring, Swathi Pakalapati

LSU Doctoral Dissertations

The adverse health e_x000B_ffects of tropospheric ozone around urban zones indicate a substantial risk for many segments of the population. This necessitates the short term forecast in order to take evasive action on days conducive to ozone formation. Therefore it is important to study the ozone formation mechanisms and predict the ozone levels in a geographic region. Multivariate statistical techniques provide a very e_x000B_ffective framework for the classifi_x000C_cation and monitoring of systems with multiple variables. Cluster analysis, sequence analysis and hidden Markov models (HMMs) are statistical methods which have been used in a wide range of studies to model the …

Task Scheduling And Placement For Reconfigurable Devices, Mostafa Elbidweihy

LSU Doctoral Dissertations

Partially reconfigurable devices allow the execution of different tasks at the same time, removing tasks when they finish and inserting new tasks when they arrive. This dissertation investigates scheduling and placing real-time tasks (tasks with deadline) on reconfigurable devices. One basic scheduler is the First-Fit scheduler. By allowing the First-Fit scheduler to retry tasks while they can satisfy their deadlines, we found that its performance can be enhanced to be better than other schedulers. We also proposed a placement idea based on partitioning the reconfigurable area into regions of various widths, assigning a task to a region based on its …

State Feedback Control With Time Delay, Akshay Nareshraj Singh

LSU Doctoral Dissertations

In this thesis we start with an introduction to the theory of vibration control. We broadly classify the control methods into passive and active schemes. We introduce the problem of state feedback control and provide the classical solution in the form of Ackermann formula. We then identify the limitations of the classical approach and present the more elegant solution of partial pole assignment without spillover. We highlight the problem with model uncertainties and describe the method of pole assignment using data from measured receptances. This approach is extended for pole assignment for a linear vibrating system by using state feedback …

A Decision Making Framework For Hurricane Evacuation And Sheltering, Jason Fennell

LSU Master's Theses

There are few tools currently available to emergency managers to assist in making decisions about whether to evacuate, shelter locally, or shelter-in-place, and none of these tools explicitly consider risk to life safety. A methodology was developed to provide risk-based guidance for evacuation versus sheltering decision making. The hurricane hazards considered in the developed methodology are high winds, storm surge flooding and waves, and rainfall flooding. Vulnerability of buildings to these hazards and the associated risks to life safety are then determined. These results are compared to the hazards and risks associated with evacuation, particularly for medical special needs populations …

Mechanistic Foam Modeling And Simulations: Gas Injection During Surfactant-Alternating-Gas Processes Using Foam-Catastrophe Theory, Ali Afsharpoor

LSU Master's Theses

The use of foam for mobility control is a promising means to improve sweep efficiency in subsurface applications such as improved/enhanced oil recovery and aquifer remediation. Foam can be introduced into geological formations by injecting gas and surfactant solutions simultaneously or alternatively. Alternating gas and surfactant solutions, which is often referred to as surfactant-alternating-gas (SAG) process, is known to effectively create fine-textured strong foams due to fluctuation in capillary pressure. Recent studies show that foam rheology in porous media can be characterized by foam-catastrophe theory which exhibits three foam states (weak-foam, strong-foam, and intermediate states) and two strong-foam regimes (high-quality …

Effects Of Processing Parameters On The Embrittlement Of Self Reacting Friction Stir Welds, David Eric Taylor

LSU Master's Theses

Friction Stir Welding (FSW) has been adopted as one of the major welding processes for joining Aluminum. Many aerospace and marine structures are welded through this novel FSW processes currently. The Lockheed Martin Space Systems (LMSS), Michoud Operations, in New Orleans is continuously pursuing Friction Stir Welding technologies in its efforts to advance fabrication of the external tanks of the space shuttle. Recently, a reduction in mechanical strength (embrittlement) has been observed especially in self-reacting (SR) friction stir welds. This strength reduction was attributed to Residual Oxide Defects (ROD) but the exact reasons for this type of behavior needed to …

Enhancing Reductive Dechlorination Of Chlorinated Ethenes And Ethanes In A Natural Treatment System, Caroline Burda

LSU Master's Theses

Chlorinated solvent contamination continues to plague sites around the world. In many cases, lower chlorinated daughter products build up and remain in ground waters and soils. A Bio-Filter/Phytobed (BFP) system has been developed to replace a traditional pump and treat technology currently operating at the ReSolve Superfund site in North Dartmouth, MA. Pilot scale testing at the facility displayed a significant acclimation period prior to microbial dechlorination, as well as delayed degradation of chlorinated ethanes. Microcosm studies suggest that acidic conditions, possibly created by the peat mixture used to construct the bio-filter, inhibited bacterial growth. The neutralization of trench pH …

Third Order Cmos Decimator Design For Sigma Delta Modulators, Hemalatha Mekala

LSU Master's Theses

A third order Cascaded Integrated Comb (CIC) filter has been designed in 0.5μm n-well CMOS process to interface with a second order oversampling sigma-delta ADC modulator. The modulator was designed earlier in 0.5μm technology. The CIC filter is designed to operate with 0 to 5V supply voltages. The modulator is operated with ±2.5V supply voltage and a fixed oversampling ratio of 64. The CIC filter designed includes integrator, differentiator blocks and a dedicated clock divider circuit, which divides the input clock by 64. The CIC filter is designed to work with an ADC that operates at a maximum oversampling clock …

Hearing Assessment Of Forest Loggers, Antonio A. Fonseca

LSU Master's Theses

Forest logging is the process in which trees are cut down for forest management and/or timber harvest. According to OSHA, logging is the most dangerous occupation in the United States. It consistently represents one of the most hazardous industries, with a fatality rate more than 21 times higher than the rate for all workers in the United States. Yet, little research has been performed to determine the long term effect of noise on forest loggers. OSHA regulations state that the maximum permissible hearing in an 8 hour shift should not exceed 90 dB. Occupational noise exposure is recognized as a …

Aerodynamic And Heat Transfer Studies In A Combustor-Fired, Fixed-Vane Cascade With Film Cooling, James William Post

LSU Master's Theses

Pressure and heat transfer data has been generated in a high-pressure, high-temperature vane cascade. This cascade differs from many others seen in typical low-pressure facilities using room temperature air. Primarily, a natural gas-fired combustor generates realistic turbulence profiles in the high-temperature exhaust gases that pass through the vane cascade. The fixed-vane cascade test sections have film cooling holes machined into the surfaces in arrangements that closely model configurations seen in real-life first-row nozzle guide vanes (NGV). Theoretical coolant jet-to-crossflow blowing ratios (M) range from 0.5 to 3.0. Coolant jet-to-crossflow theoretical density ratios (DR) used for typical tests vary between 1.0 …

Sophisticated Denial-Of-Service Attack Detections Through Integrated Architectural, Os, And Appplication Level Events Monitoring, Ran Tao

LSU Master's Theses

As the first step to defend against DoS attacks, Network-based Intrusion Detection System is well explored and widely used in both commercial tools and research works. Such IDS framework is built upon features extracted from the network traffic, which are application-level features, and is effective in detecting flooding-based DoS attacks. However, in a sophisticated DoS attack, where an attacker manages to bypass the network-based monitors and launch a DoS attack locally, sniffer-based methods have difficulty in differentiating attacks with normal behaviors, since the malicious connection itself behaves in the same manner of normal connections. In this work, we study a …

Assessment Of Target Purity Difference For A Louisiana Sugar Mill, Luz Stella Polanco

LSU Master's Theses

The main goals of a “raw” sugarcane factory are to have an efficient profitable operation with the required sugar quality and maximum sugar recovery. The loss of sugar to final molasses accounts for 45 to 47% of the total sugar losses. An estimation of the average cost of the manufacturing losses for the 2007 harvest season was approximately $9 million – the sugar lost to the final molasses accounts for approximately 50% of this cost (Salassi, 2008). For final molasses, the “Target Purity” (or equilibrium purity) refers to the minimum level of sucrose that theoretically remains in solution for a …

Assessing The Accuracy Of Task Time Prediction Of An Emerging Human Performance Modeling Software - Cogtool, Oluwakemi Damilola Adio

LSU Master's Theses

There is a need for a human performance modeling tool which not only has the ability to accurately estimate skilled user task time for any interface design, but can be used by modelers with little or no programming knowledge and at a minimal cost. To fulfill this need, this research investigated the accuracy of task time prediction of a modeling tool – CogTool - on two versions of an interface design used extensively in the petrochemical industry – DeltaV. CogTool uses the KeyStroke Level Model (KLM) to calculate and generate time predictions based on specified operators. The data collected from …

On The Effects Of Peripheral Sliding Velocity And Operating Differential Pressure In Rotary O-Ring Seals, Karan Lingerkar

LSU Master's Theses

An O-ring seal is of paramount importance in hydraulic and pneumatic machinery used in oil and gas drilling processes. O-ring seals are generally employed to contain the environments of working fluids existing on either side of the seal from interacting with each other, to maintain a uniform pressure chamber and to eliminate the environmental contaminants that interact at the rubbing interface. Failure of dynamic O-rings in hydraulic and pneumatic machinery often results in considerable productivity loss to the chemical and petrochemical industries. Therefore, it is highly important to determine the life of an O-ring for these applications under various operating …

Freeway Crash And Lane Compliance Under Truck Lane Restriction And Differential Speed Limit, Murat Korkut

LSU Master's Theses

In the last decade, several fatal truck related crashes occurred on the elevated freeway over the Atchafalaya Basin. In an attempt to reduce the crash rates, the Louisiana Department of Transportation and Development implemented two policies to regulate the truck traffic on this rural divided freeway that has two lanes in each direction of flow. These policies restricted truck traffic to the right lane and reduced the maximum truck speed limit to 55-mph. On the other hand, maximum car speed limit was kept at 60-mph. The changes took place in 2003. While the policies were in effect, crash and traffic …

Development And Operational Analysis Of Highway Alternating Merge Transition Zones, Wakeel Ishola, Anthony Idewu

LSU Doctoral Dissertations

The design and control of work zone traffic control areas is governed by standards published by the United States Department of Transportation (US-DOT) and documented in the Manual for Uniform Control Devices (MUTCD). While these configurations have evolved over time to reflect safer and more efficient management practices and have become familiar to drivers, they are also recognized as areas of vehicle conflict that can cause congestion and safety problems. As part of this research, a new design has been developed that has the potential to lessen the detrimental effects of lane closures in work zones. This new concept, known …