Engineering Commons^™

Testing Coulwave For Use In Modeling Cross-Shore Sand Transport And Beach Profile Evolution, Patrick Michael Cooper

UNF Graduate Theses and Dissertations

Realistic, reliable, and effective modeling of cross-shore sediment transport is not present in the current literature. Building that model requires the accurate recreation of breaking wave processes in the nearshore. To develop that first step for an as-yet-to-be-designed model, multiple phase-resolving wave transformation algorithms are reviewed for in-depth investigation. The COULWAVE model is selected for robust testing. Testing of the COULWAVE model shows that, although capable of recreating realistic results, it does not adequately describe major wave characteristics in the surf zone, across a wide range of conditions, to warrant use in a future cross-shore sediment transport model.

Landing-Gear Impact Response: A Non-Linear Finite Element Approach, Tuan H. Tran

UNF Graduate Theses and Dissertations

The primary objective of this research is to formulate a methodology of assessing the maximum impact loading condition that will incur onto an aircraft’s landing gear system via Finite Element Analysis (FEA) and appropriately determining its corresponding structural and impact responses to minimize potential design failures during hard landing (abnormal impact) and shock absorption testing. Both static and dynamic loading condition were closely analyzed, compared, and derived through the Federal Aviation Administration’s (FAA) airworthiness regulations and empirical testing data.

In this research, a nonlinear transient dynamic analysis is developed and established via NASTRAN advanced nonlinear finite element model (FEM) to …

A Bayesian Nonparametric Multiple Testing Procedure For Comparing Several Treatments Against A Control, Luis Gutiérrez, Andrés Barrientos, Jorge González, Daniel Taylor-Rodríguez

Mathematics and Statistics Faculty Publications and Presentations

We propose a Bayesian nonparametric strategy to test for differences between a control group and several treatment regimes. Most of the existing tests for this type of comparison are based on the differences between location parameters. In contrast, our approach identifies differences across the entire distribution, avoids strong modeling assumptions over the distributions for each treatment, and accounts for multiple testing through the prior distribution on the space of hypotheses. The proposal is compared to other commonly used hypothesis testing procedures under simulated scenarios. Two real applications are also analyzed with the proposed methodology.

A Case For Open Mission Systems In Dod Aircraft Avionics, Michael J. Brown, R. David Fass, Jonathan D. Ritschel

Faculty Publications

The DOD is adopting open mission systems (OMS) as the future in the military aviation environment. OMS proponents promise reduced costs and truncated schedules through increased competition in the marketplace and reduced coding efforts. To the best of our knowledge, no studies have examined the success of these open architectures in the DOD. Therefore, we investigate costs and schedule for a recent DOD avionics OMS demonstration platform in comparison to 13 historically analogous programs.

Noninvasive Diagnosis Of Irritable Bowel Syndrome Via Bowel Sound Features: Proof Of Concept, Xuhao Du, Gary Allwood, K. Mary Webberley, Andrisha-Jade Inderjeeth, Adam Osseiran, Barry James Marshall

Research outputs 2014 to 2021

INTRODUCTION: Irritable bowel syndrome (IBS) is a common and debilitating disorder estimated to affect approximately 11% of the world's population. Typically, IBS is a diagnosis of exclusion after patients undergo a costly and invasive colonoscopy to exclude organic disease. Clinician's and researchers have identified a need for a new cost-effective, accurate, and noninvasive diagnostic test for IBS.

METHODS: Using a diagnostic case-control study, we explored the use of bowel sounds to characterize IBS with a view to diagnostic use. We recruited participants with an existing clinical diagnosis of IBS or healthy (asymptomatic) digestive systems. We recorded bowel sounds for 2 …

Natural Source Zone Depletion Of Lnapl: A Critical Review Supporting Modelling Approaches, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner, Trevor P. Bastow, Geoffrey J. Puzon

Research outputs 2014 to 2021

Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) includes partitioning, transport and degradation of LNAPL components. NSZD is being considered as a site closure option during later stages of active remediation of LNAPL contaminated sites, and where LNAPL mass removal is limiting. To ensure NSZD meets compliance criteria and to design enhanced NSZD actions if required, residual risks posed by LNAPL and its long term behaviour require estimation. Prediction of long-term NSZD trends requires linking physicochemical partitioning and transport processes with bioprocesses at multiple scales within a modelling framework. Here we expand and build on the knowledge …

Recent Developments In Solar Energy-Harvesting Technologies For Building Integration And Distributed Energy Generation, Mikhail Vasiliev, Mohammad Nur-E-Alam, Kamal Alameh

Research outputs 2014 to 2021

We present a review of the current state of the field for a rapidly evolving group of technologies related to solar energy harvesting in built environments. In particular, we focus on recent achievements in enabling the widespread distributed generation of electric energy assisted by energy capture in semi-transparent or even optically clear glazing systems and building wall areas. Whilst concentrating on recent cutting-edge results achieved in the integration of traditional photovoltaic device types into novel concentrator-type windows and glazings, we compare the main performance characteristics reported with these using more conventional (opaque or semi-transparent) solar cell technologies. A critical overview …

Optimization Of Well Pad Design And Drilling - Well Clustering, Aleksandr Abramov

Research outputs 2014 to 2021

A model accounting for more than 30 parameters of drilling projects, and a computer program to enumerate groupings of the wells of a pad with consequent calculations of technical-economic characteristics, are developed and tested. Seven drilling scenarios for a 24-well pad with different starting oil flow rates for the wells are studied. Optimal well groupings in terms of Net Present Value (NPV) for three discount rates and five oil production decline rates have been found. The results show that: NPV-maximizing well pad designs with unequal (varying) numbers of wells in groups (clusters) may require only slight alterations …

Facile Synthesis Of Di-Mannitol Adipate Ester-Based Zinc Metal Alkoxide As A Bi-Functional Additive For Poly(Vinyl Chloride), Yuepeng Li, Degang Li, Wenyuan Han, Manqi Zhang, Bing Ai, Lipeng Zhang, Hongqi Sun, Zhen Cui

Research outputs 2014 to 2021

A new di-mannitol adipate ester-based zinc metal alkoxide (DMAE-Zn) was synthesized as a bi-functional poly(vinyl chloride) (PVC) thermal stabilizer for the first time. The materials were characterized with Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Characterization results confirmed the formation of Zn–O bonds in DMAE-Zn, and confirmed that DMAE-Zn had a high decomposition temperature and a low melting point. The thermal stability of DMAE-Zn on PVC also was tested by a conductivity test, a thermal aging test, and a UV-visible spectroscopy (UV-VIS) test. PVC stabilized by DMAE-Zn had a good initial color and excellent long-term stability. UV-VIS also …

Phase Separation And Enhanced Wear Resistance Of Cu88fe12 Immiscible Coating Prepared By Laser Cladding, Shuzhen Zhao, Shengfeng Zhou, Min Xie, Xiaoqin Dai, Dongchu Chen, Laichang Zhang

Research outputs 2014 to 2021

In order to eliminate the microstructure segregation of Cu–Fe immiscible alloys which characterized with a liquid miscible gap, the Cu88Fe12 (wt.%) immiscible coating was prepared by laser cladding. The phase separation characteristic and wear resistance of the Cu88Fe12 (wt.%) immiscible coating were also investigated. The results show that the size of the milled Cu88Fe12 composite powder is reduced comparing to that of the un-milled powder due to fracturing during mechanical milling. Moreover, the demixing or delamination disappears in the Cu88Fe12 immiscible coating and a large amount of face-centered-cubic (fcc) γ-Fe and body-centered-cubic (bcc) α-Fe particles are dispersed in the face-centered-cubic …

Effect Of Pretreatment Process On Scale Formation In The Re-Boiler Section Of Monoethylene Glycol Regeneration Plant, Ammar Al Helal, Adam Soames, Stefan Iglauer, Ahmed Barifcani, Rolf Gubner

Research outputs 2014 to 2021

Monoethylene glycol (MEG) regeneration plants often use pretreatment vessels to precipitate divalent cations, such as Fe²⁺, Ca²⁺, and Mg²⁺, in order to avoid or reduce fouling in downstream reboilers and heat exchangers. This pretreatment process operates under alkaline conditions and moderate temperatures (~ 80 °C) to accelerate the formation of low-solubility divalent salts. The objective of the present research was to determine whether the pretreatment process could be minimized, without negatively impacts on the MEG regeneration process from to the formation of scale on the heater bundle in the presence of low concentrations of …

Editorial: Environmental Catalysis And The Corresponding Catalytic Mechanism, Zhimin Ao, Hongqi Sun, Andres Fullana

Research outputs 2014 to 2021

The ever growing environmental pollution has stimulated the rapid development of environmental catalysis in recent years. Environmental catalysis is a multidisciplinary research field for which more and more chemists, materials scientists, as well as environmentalists have devoted their efforts working in this field because of the bright potentials in improving human health and life quality...

Optimal Allocation Of Distributed Energy Storage Systems To Improve Performance And Power Quality Of Distribution Networks, Choton K. Das, Octavian Bass, Thair S. Mahmoud, Ganesh Kothapalli, Navid Mousavi, Daryoush Habibi, Mohammad A.S. Masoum

Research outputs 2014 to 2021

The placement of grid-scale energy storage systems (ESSs) can have a significant impact on the level of performance improvements of distribution networks. This paper proposes a strategy for optimal allocation of distributed ESSs in distribution networks to simultaneously minimize voltage deviation, flickers, power losses, and line loading. The optimal ESS allocation is investigated through the PQ injection (considering a variable power factor on the dispatch of ESSs) and the results are compared in terms of performance and power quality improvements. An IEEE-33 bus distribution system (medium voltage), having a high influence of renewable (wind and solar) distributed generation, is used …

Effect Of Al Alloying On Cavitation Erosion Behavior Of Tasi2 Nanocrystalline Coatings, Jiang Xu, Shuai Kang Zhang, Xiao Lin Lu, Shuyun Jiang, Paul Munroe, Zong-Han Xie

Research outputs 2014 to 2021

To broaden the scope of non-aerospace applications for titanium-based alloys, both hexagonal C40 binary TaSi₂ and ternary Al alloyed TaSi₂ nanocrystalline coatings were exploited to enhance the cavitation erosion resistance of Ti-6Al-4V alloy in acidic environments. To begin with, the roles of Al addition in influencing the structural stability and mechanical properties of hexagonal C40 Ta(Si_1-xAl_x)₂ compounds were modelled using first-principles calculations. The calculated key parameters, such as Pugh's index (B/G ratio), Poisson's ratio, and Cauchy pressures, indicated that there was a threshold value for Al addition, below which the increase of Al …

Numerical Study Of Periodic Magnetic Field Effect On 3d Natural Convection Of Mwcnt-Water/Nanofluid With Consideration Of Aggregation, Lioua Kolsi, Hakan F. Oztop, Kaouther Ghachem, Mohammed A. Almeshaal, Hussein A. Mohammed, Houman Babazadeh, Nidal Abu-Hamdeh

Research outputs 2014 to 2021

In this paper, a numerical study is performed to investigate the effect of a periodic magnetic field on three-dimensional free convection of MWCNT (Mutli-Walled Carbone Nanotubes)-water/nanofluid. Time-dependent governing equations are solved using the finite volume method under unsteady magnetic field oriented in the x-direction for various Hartmann numbers, oscillation periods, and nanoparticle volume fractions. The aggregation effect is considered in the evaluation of the MWCNT-water/nanofluid thermophysical properties. It is found that oscillation period, the magnitude of the magnetic field, and adding nanoparticles have an important effect on heat transfer, temperature field, and flow structure. © 2019 by the authors.

Fire Performance Of Heavyweight Self-Compacting Concrete And Heavyweight High Strength Concrete, Farhad Aslani, Fatemeh Hamidi, Qilong Ma

Research outputs 2014 to 2021

In this study, the fresh and hardened state properties of heavyweight self-compacting concrete (HWSCC) and heavyweight high strength concrete (HWHSC) containing heavyweight magnetite aggregate with 50, 75, and 100% replacement ratio, and their performance at elevated temperatures were explored experimentally. For fresh-state properties, the flowability and passing ability of HWSCCs were assessed by using slump flow, T500 mm, and J-ring tests. Hardened-state properties including hardened density, compressive strength, and modulus of elasticity were evaluated after 28 days of mixing. High-temperature tests were also performed to study the mass loss, spalling of HWSCC and HWHSC, and residual mechanical properties at 100, …

Beta-Type Ti-Nb-Zr-Cr Alloys With Large Plasticity And Significant Strain Hardening, Syed F. Jawed, Chirag D. Rabadia, Y. J. Liu, L. Q. Wang, Y. H. Li, X. H. Zang, Laichang C. Zhang

Research outputs 2014 to 2021

A series of Ti-25Nb-8Zr-xCr (x = 0, 2, 4, 6, 8 wt%) alloys were designed based on DV-Xα cluster method and e=a-Δr diagram with an anticipation to obtain high plasticity and significant strain hardening. The designed alloys were produced through cold crucible levitation melting technique in order to effectively investigate their micro-structures and mechanical properties. The addition of Cr significantly enhances the β stability in the microstructures of the Ti-25Nb-8Zr-xCr alloys. Both yield strength and hardness of the studied alloys increase due to the effect of solid-solution strengthening. By contrast, the plasticity, maximum strength and strain hardening rate are influenced …

Properties Of Ambient-Cured Normal And Heavyweight Geopolymer Concrete Exposed To High Temperatures, Farhad Aslani, Zohaib Asif

Research outputs 2014 to 2021

Ambient-cured heavyweight geopolymer concrete (HWGC) is a new type of concrete that combines the benefits of both heavyweight concrete (HWC) and geopolymer concrete (GC). HWGC provides proper protection from the sources that emit harmful radiations in medical and nuclear industries. Furthermore, HWGC may also be used in offshore structures for pipeline ballasting and similar underwater structures. In this study, heavyweight aggregates (magnetite) have been used and replaced by normal-weight coarse aggregates in GC at volume ratios of 50, 75, and 100% to attain heavyweight classification according to British standards. This study investigates the impacts of high temperatures on standard ambient-cured …

Taylor's Slope Stability Chart For Combined Effects Of Horizontal And Vertical Seismic Coefficients, Pragyan Sahoo, Sanjay Kumar Shukla

Research outputs 2014 to 2021

Design standards and codes of practice on earth slope stability often recommend the pseudo-static method of analysis for determining the factor of safety of a slope subjected to seismic forces. In most pseudo-static methods of analysis, the horizontal seismic force is considered without due weightage to vertical seismic force. In the past, Taylor's stability chart for a homogeneous cohesive-frictional soil slope has been extended to consider the effect of horizontal seismic force only. In this paper, an attempt is made to develop an analytical formulation considering both horizontal and vertical seismic forces in order to estimate the factor of safety …

Real-Time Classification Of Multivariate Olfaction Data Using Spiking Neural Networks, Arnup Vanarse, Adam Osseiran, Alexander Rassau, Therese O'Sullivan, Jonny Lo, Amanda Devine

Research outputs 2014 to 2021

Recent studies in bioinspired artificial olfaction, especially those detailing the application of spike-based neuromorphic methods, have led to promising developments towards overcoming the limitations of traditional approaches, such as complexity in handling multivariate data, computational and power requirements, poor accuracy, and substantial delay for processing and classification of odors. Rank-order-based olfactory systems provide an interesting approach for detection of target gases by encoding multi-variate data generated by artificial olfactory systems into temporal signatures. However, the utilization of traditional pattern-matching methods and unpredictable shuffling of spikes in the rank-order impedes the performance of the system. In this paper, we present an …

Particle Size-Dependent Microstructure, Hardness And Electrochemical Corrosion Behavior Of Atmospheric Plasma Sprayed Nicrbsi Coatings, Peng Sang, Liang-Yu Chen, Cuihua Zhao, Ze-Xin Wang, Haiyang Wang, Sheng Lu, Dongpo Song, Jia-Huan Xu, Lai-Chang Zhang

Research outputs 2014 to 2021

Particle size is a critical consideration for many powder coating-related industries since it significantly influences the properties of the produced materials. However, the effect of particle size on the characteristics of plasma sprayed NiCrBSi coatings is not well understood. This work investigates the microstructures, hardness and electrochemical corrosion behavior of plasma sprayed NiCrBSi coatings synthesized using different-sized powders. All coatings mainly consist of Ni, N3B, CrB, Cr7C3 and Cr3C2 phases. The coatings produced by small particles (50–75 μm) exhibit lower porosity (2.0 ± 0.8%). Such coatings show a higher fraction (15.5 vol.%) of the amorphous phase and lower hardness (700 …

Capacitive Sensor And Its Calibration: A Technique For The Estimation Of Solid Particles Flow Concentration, Usama Abrar, Liu Shi, Nasif R. Jaffri, Qin Li, Mian W. Omar, Hassan R. Sindhu

Research outputs 2014 to 2021

The precise and accurate measurement of flow rate in the batch flow of the solid particles is of primary importance in many process industries for the improvement of the efficiency of the system. Many techniques developed for the measurement of mass flow rate. The capacitive sensors has a significance of being non-invasive, higher accuracy and low cost for mass flow measurement despite the fact that many factors adversely affect the performance- including non-uniform flow, multiphase flow, temperature, pressure, and moisture in the solid particles. This paper covers preliminary investigations of the offline estimation of mass flow concentration based upon the …

Initial Field Testing Results From Building-Integrated Solar Energy Harvesting Windows Installation In Perth, Australia, Mikhail Vasiliev, Mohammad Nur-E-Alam, Kamal Alameh

Research outputs 2014 to 2021

We report on the field testing datasets and performance evaluation results obtained from a commercial property-based visually-clear solar window installation site in Perth-Australia. This installation was fitted into a refurbished shopping center entrance porch and showcases the potential of glass curtain wall-based solar energy harvesting in built environments. In particular, we focus on photovoltaic (PV) performance characteristics such as the electric power output, specific yield, day-to-day consistency of peak output power, and the amounts of energy generated and stored daily. The dependencies of the generated electric power and stored energy on multiple environmental and geometric parameters are also studied. An …

Assesment Of Electricity Excess In An Isolated Hybrid Energy System: A Case Study Of A Dangiwada Village In Rural Nepal, Ashish Shrestha, Lalit Bickram Rana, Ajay Singh, Sudip Phuyal, Anil Ghimire, Roshan Giri, Roshan Kattel, Kedar Karki, Shailendra Kumar Jha

Research outputs 2014 to 2021

The increasing demand of power can be fulfilled through different architectures and electricity supply models by utilizing the available local resources. But most of the isolated energy system suffers from high energy cost and unreliable energy supply. This study identifies different electricity supply models to fulfill the dynamic demand of power in a remote area, which is analyzed in terms of cost of energy and causes for the high cost of energy. Among different factors, the presence of unusable energy (Electricity Excess) produced by the energy system during fulfillment of the demand is found to be major one cause for …

Thermal Performance Of An Evacuated Tube Heat Pipe Solar Water Heating System In Cold Season, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

This study evaluates the performance of a heat pipe solar water heating system to meet a real residential hot water consumption pattern theoretically and experimentally under non-ideal climatic conditions during a cold day in Perth, Western Australia. A mathematical model was developed and used to calculate the optimum number of glass tubes of the heat pipe solar collector. Based on the obtained data, an experimental rig with 25 glass tubes was designed, built, and tested as the temperature changes after 25 tubes reached the insignificant value of 0.6%. The results showed that hot water extraction had significant impact on the …

Phase Interaction Induced Texture In A Plasma Sprayed-Remelted Nicrbsi Coating During Solidification: An Electron Backscatter Diffraction Study, Liang-Yu Chen, Tianxiang Xu, Haiyang Wang, Peng Sang, Sheng Lu, Ze-Xin Wang, Shujin Chen, Lai-Chang Zhang

Research outputs 2014 to 2021

Although considerable endeavors have been dedicated to investigate the microstructures of the remelting-enhanced NiCrBSi coatings, the textures in the remelted coatings, which may result in property anisotropy, are rarely studied. In this work, the recrystallized fractions, grain orientations and interphase boundaries for Ni, Ni₃B and CrB in a plasma sprayed-remelted NiCrBSi coating were investigated by electron backscatter diffraction. The results demonstrate that the texture is induced by phase interaction during solidification. Cooling from the liquid, the firstly formed Ni grains possess a cube fiber texture of {001}〈001〉. The successively formed Ni₃B colonies are randomly oriented and …

Degradation And Hydrate Phase Equilibria Measurement Methods Of Monoethylene Glycol, Khalid Alef, Stefan Iglauer, Ahmed Barifcani

Research outputs 2014 to 2021

Monoethylene glycol (MEG), a common chemical used for the inhibition of gas hydrate formation may undergo degradation in the regeneration/reclamation process. Limited research exists on the effect of degradation of MEG on hydrate formation, production facilities and equipment especially in the presence of other chemical additives. The proposed method allows for streamlining the process of preparing, degrading and analysis of MEG solutions for hydrate testing and degradation products.

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Procedure to prepare accurate MEG solutions avoiding oxidative degradation of MEG (i.e., controlling oxygen ingress).

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Two methods are suggested to mimic field-like degradation of MEG solutions (i.e., degradation by reclamation …

Chemically Dealloyed Fe-Based Metallic Glass With Void Channels-Like Architecture For Highly Enhanced Peroxymonosulfate Activation In Catalysis, J.C. Wang, S.X. Liang, Z. Jia, W.C. Zhang, W.M. Wang, Y.J. Lui, J. Lu, L.C Zhang

Research outputs 2014 to 2021

Metallic glasses (MGs) with their intrinsic disordered atomic structure and widely controllable atomic components have recently emerged as fascinating functional materials in wastewater treatment. Compared to crystalline alloys, the less-noble atomic components in monolithic metallic glass are more efficient to be selectively dissolved during dealloying process. This work reported a facile chemical dealloying approach to fabricate a void channels-like structured MG with the elemental components of Fe73.5Si13.5B9Cu1Nb3 for methylene blue (MB) degradation. Results indicated that the dealloyed Fe73.5Si13.5B9Cu1Nb3 MGs with the void channels-like morphology presented a significant improvement of catalytic efficiency and reusability. The dye degradation reaction rate (kobs) of …

Strategies To Improve The Thermal Performance Of Heat Pipe Solar Collectors In Solar Systems: A Review, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

Invention of evacuated tube heat pipe solar collectors (HPSCs) was a huge step forward towards resolving the challenges of conventional solar systems due to their unique features and advantages. This has led to their utilization in a wide range of solar applications surpassing other conventional collectors. However, relatively low thermal efficiency of heat pipe solar (HPS) systems is still the major challenge of solar industry evidenced by numerous studies conducted mainly during the last decade to improve their efficiency. To date, several review papers have been published summarizing studies relevant to utilization of HPSCs in various thermal applications. However, to …

Calculation Of Critical Water Flow Rates For Wildfire Suppression, Greg Penney, Daryoush Habibi, Marcus Cattani, Murray Carter

Research outputs 2014 to 2021

Predicting water suppression requirements and its impacts on firefighting strategies and logistics within the urban environment has been the subject of many previous studies, however the same level of research has yet to be applied in the realm of wildfire suppression. To work towards addressing this knowledge gap, this paper provides guidance for Incident Controllers in relation to critical water flow rates required to extinguish large wildfire across a wide range of forest fuel loads, fire weather and active fire front depths. This is achieved through mathematical empirical analysis of water flow rates required for head fire suppression during 540 …