Engineering Commons^™

Investigation Of The Flow Field Inside A Drainage System: Gully - Pipe - Manhole, N. A. Beg, R. F. Carvalho, J. Leandro, P. Lopes, L. Cartaxo

International Junior Researcher and Engineer Workshop on Hydraulic Structures

No abstract provided.

Design, Testing, Analysis, And Material Properties Of Carbon Fiber Reinforced Polymers, Andrew Miner, Simon Jones

Rose-Hulman Undergraduate Research Publications

Rose-Hulman Institute of Technology excels in many fields, however in the field of Carbon Fiber Reinforced Polymers (CFRPs) there is a significant lack of knowledge. Over the 2015 summer I started accumulating and building a knowledge base for the institute to help future students who have interest in this ever expanding field. This report covers many of the learnings I found in the structures of fiber reinforced polymers, manufacturing processes and controls, testing procedures and standards, important considerations in the design process of CFRPs, and analysis capabilities and methods. This report is organized as a series of short guides to …

A Perspective On Environmentally-Induced Cracking, R.M. Latanision, A.K. Vasudevan

International Workshop on the Environmental Damage in Structural Materials Under Static Load/Cyclic Loads at Ambient Temperatures

The premature failure of engineering alloys in service is often associated with exposure to unintended environmental chemistry. High strength carbon steels and stainless steel will fail prematurely if exposed under tensile stress to absorbed atomic hydrogen. This is known as hydrogen embrittlement. Similarly, when aluminum alloys are exposed to liquid mercury, they are likely to crack prematurely if tensile stresses are present This is an example of liquid metal embrittlement. Silicate glass cracks in the presence of water, a phenomenon known as static fatigue of glass. Plastics fail prematurely in the presence of organic solvents. Service environments that contain soluble …

An Investigation Into The Effectiveness Of Hedonic Features In Regression Models For Domestic Rental Prices, Peter Prunty

Dissertations

Housing is a fundamental human right. Increasing rents and rising unemployment contribute to increased rates of homelessness. Traditionally housing prices are determined by supply and demand. This project will investigate the relationship between hedonic features and domestic rental prices in California and New York, using multivariate regression models. The literature outlines a number of approaches taken to model real estate pricing using hedonic regression.

Two models were created to analyse the difference between California and New York. Features were selected using correlation analysis. Some features were derived using logarithmic and dummy feature transformations. The models themselves were evaluated by assessing …

Micromechanisms Of Fracture Propagation In Glassy Polymers, Matteo Ciccotti, Matthieu George, Yannick Nziakou, Guillaume Fischer, Anne-Caroline Genix, Bruno Bresson, Stéphane Roux

International Workshop on the Environmental Damage in Structural Materials Under Static Load/Cyclic Loads at Ambient Temperatures

While most glassy polymers are nominally brittle at macroscopic scales, they are known to exhibit plastic deformation in indentation, scratching, and microcutting when the loaded region is sufficiently small. The same applies to the micrometer size process zone at the tip of a propagating crack. While the presence and approximate size of this microscale plastic zone is well described by the Dugdale model, the prediction of the toughness of these materials is not possible without accounting for the details of the local large strain field and the work hardening behaviour of these polymers, which can be inferred from their response …

Investigation Into The Predictive Capability Of Macro-Economic Features In Modelling Credit Risk For Small Medium Enterprises, Kevin Mctiernan

Dissertations

This research project investigates the predictive capability of macro-economic features in modelling credit risk for small medium enterprises (SME/SMEs). There have been indications that there is strong correlation between economic growth and the size of the SME sector in an economy. However, since the financial crisis and consequent policies and regulations, SMEs have been hampered in attempts to access credit. It has also been noted that while there is a substantial amount of credit risk literature, there is little research on how macro-economic factors affect credit risk. Being able to improve credit scoring by even a small amount can have …

A Method For Corrosion-Fatigue Life Prediction, Daniel Kujawski

International Workshop on the Environmental Damage in Structural Materials Under Static Load/Cyclic Loads at Ambient Temperatures

It is well recognized that environment has significant effects on the failure of cyclically loaded members/structures Existing experimental data indicates that fatigue life is much shorter in corrosive environment that in more inert environment such as a dry air or vacuum. This paper presents a method and strategy to predict/estimate life under corrosion-fatigue. A corrosion fatigue factor k_corr is defined as the ratio of the fully-reversed stress amplitude in air, (_a)_air, over that in corrosive environment, (_a)_corr, for a given fatigue life in terms of a number of cycles to …

Conference Program, A.K. Vasudevan, Ronald Latanision, Henry Holroyd, Neville Moody

International Workshop on the Environmental Damage in Structural Materials Under Static Load/Cyclic Loads at Ambient Temperatures

No abstract provided.

Dango (Doings And Goings On)- Vol. 22 | Issue 2, Matthew Kimball, Haley Stien, Cecily Towell, Rusty Towell, Aric Tate, Caleb Hicks, Zhaojia Xi, Joshua Daniel Martinez, Paul Carstens, Shon Watson, Reuben Byrd, Mike Daugherity, Donald Isenhower

DANGO: Doings and Goings On: Summer Research Newsletter, Department of Engineering and Physics

Summer Research Newsletter for ACU's Engineering and Physics Department

Nano-Photonic Waveguides For Chemical And Biomedical Sensing, Surya Venkatasekhar Cheemalapati

USF Tampa Graduate Theses and Dissertations

In this dissertation, advances in the fields of Photonics, and Plasmonics, and specifically, single cell analysis and waveguide sensing will be addressed. The first part of the dissertation is on Finite Difference Time Domain (FDTD) optimization and experimental demonstration of a nano-scale instrument that allows sensing at the cellular and subcellular levels. A new design of plasmonic coupler into a nanoscale waveguide is proposed and optimized using FDTD simulations. Following this, a subcellular nanoendoscope that can locally excite fluorescence in labelled cell organelles and collect the emitted fluorescent light for detailed spectrum analysis is fabricated and tested. The nanoendoscope has …

Graphene Quantum Dots-Based Drug Delivery For Ovarian Cancer Therapy, Yiru Qin

USF Tampa Graduate Theses and Dissertations

Ovarian cancer, one of the most dreadful malignancies of the female reproductive system, poses a lethal threat to women worldwide. In this dissertation, the objective was to introduce a novel type of graphene quantum dots (GQDs) based nano-sized drug delivery systems (DDS) for ovarian cancer treatment. As a starting point, the facile synthesis method of the GQDs was established. Subsequently, the targeting ligand,folic acid (FA), was conjugated to GQDs. Next, a FDA approved chemotherapeutic drug, Doxorubicin (DOX), was loaded to form the GQDs-FA-DOX nano-conjugation as the DDS. Moreover, the uptake profile and anti-cancer effect of the GQDs-FA-DOX were validated in …

Sim Card Forensics: Digital Evidence, Nada Ibrahim, Nuha Al Naqbi, Farkhund Iqbal, Omar Alfandi

Annual ADFSL Conference on Digital Forensics, Security and Law

With the rapid evolution of the smartphone industry, mobile device forensics has become essential in cybercrime investigation. Currently, evidence forensically-retrieved from a mobile device is in the form of call logs, contacts, and SMSs; a mobile forensic investigator should also be aware of the vast amount of user data and network information that are stored in the mobile SIM card such as ICCID, IMSI, and ADN. The aim of this study is to test various forensic tools to effectively gather critical evidence stored on the SIM card. In the first set of experiments, we compare the selected forensic tools in …

Assessing The Gap: Measure The Impact Of Phishing On An Organization, Brad Wardman

Annual ADFSL Conference on Digital Forensics, Security and Law

Phishing has become one of the most recognized words associated with cybercrime. As more organizations are being targeted by phishing campaigns, there are more options within the industry to deter such attacks. However, there is little research into how much damage these campaigns are causing organizations. This paper will show how financial organizations can be impacted by phishing and present a method for accurately quantifying resultant monetary losses. The methodology presented in this paper can be adapted to other organizations in order to quantify phishing losses across industries.

Keywords: phishing, cybercrime, economics

Wban Security Management In Healthcare Enterprise Environments, Karina Bahena, Manghui Tu

Annual ADFSL Conference on Digital Forensics, Security and Law

As healthcare data are pushed online, consumers have raised big concerns on the breach of their personal information. Law and regulations have placed businesses and public organizations under obligations to take actions to prevent such data breaches. Various vulnerabilities have been identified in healthcare enterprise environments, in which the Wireless Body Area Networks (WBAN) remains to be a major vulnerability, which can be easily taken advantage of by determined adversaries. Thus, vulnerabilities of WBAN systems and the effective countermeasure mechanisms to secure WBAN are urgently needed. In this research, first, the architecture of WBAN system has been explored, and the …

Force On A Large Sphere Immersed In An Expanded Water-Fluidized Bed Over A Wide Range Of Voidage Values, Alberto Di Renzo, Nicola Grassano, Francesco P. Di Maio

Fluidization XV

The presence of large objects immersed in a fluidized bed has been long studied in order to verify to what extent can the analogy with a buoyant body in a liquid represent the object-to-suspension interaction (1). One of the most useful information resulting from such study is the effective drag force exerted on the object and how it is related to the suspension properties, particularly with respect to the expansion degree. Implications are found also in the formulation of drag force expressions for homogeneous polydisperse systems.

In the present work an experimental series of tests has been conducted on a …

Applications Of Tribology And Fracture Mechanics To Determine Wear And Impact Attrition Of Particulate Solids In Cfb Systems, Ronald W. Breault, Samuel C. Bayham, Esmail R. Monazam

Fluidization XV

In recent years, much attention has been focused on the development of novel technologies for carbon capture and chemicals production that utilize a circulating fluidized bed configuration; examples include chemical looping combustion and circulation of temperature swing adsorbents in a CFB configuration for CO2 capture. A major uncertainty in determining the economic feasibility of these technologies is the required solids makeup rate, which, among other factors, is due to impact and wear attrition at various locations, including standpipes, cyclones, and the gas jets in fluid beds. While correlations have been developed that estimate the attrition rates at these areas, these …

Experimental Validation Of Cfd Hydrodynamic Models For Catalytic Fast Pyrolysis (Cfp), Bruce D Adkins, Travis Dudley, Neeti Kapur, Peter Blaser, James Parker

Fluidization XV

Catalytic Fast Pyrolysis (CFP) is a means of producing renewable fuels and chemicals from lignocellulosic biomass. KiOR, a world leader in this area, has developed a CFP technology along the lines of the FCC process.

In early 2015, KiOR engaged with CPFD Software to develop a new, parallel path for developing and optimizing its CFP technology. Emphasis was placed on hydrodynamics predictions, since that is one key area where KiOR’s CFP differs significantly from FCC. The KiOR-CPFD team reduced the hydrodynamics validation problem to four key milestones. Each milestone needs independent experimental validation, and must build on the previous ones: …

Combustion Of Lignin-Rich Residues With Coal In A Pilot-Scale Bubbling Fluidized Bed Reactor, Roberto Solimene, Riccardo Chirone, Antonio Cammarota, Nicola Rossi, Paolo Leoni, Piero Salatino

Fluidization XV

The deployment and the exploitation of bioethanol as automotive fuel became more and more relevant to reduce the emissions of greenhouse gases and to limit the dependence on countries supplying fossil fuels. However, the production of second-generation bioethanol, i.e. using lignocellulosic biomass or scraps of agricultural crops as feedstock, generates a waste stream consisting of lignin-rich residues whose fate has to be found (1-2). This work aims at investigating the combustion of lignin-rich residues (in the following simply called lignin), coming from a second-generation bioethanol production plant, with coal in a pilot-scale bubbling fluidized bed combustor (FBC). The pilot-scale 200kW …

Micro/Meso Simulations Of A Fluidized Bed With Heat Transfer, Florian Euzenat, Anthony Wachs, Abdelkader Hammouti, Pascal Fede, Eric Climent

Fluidization XV

Particulate flows encountered in fluidized beds are frequently used in industrial applications (refining, energy, chemicals/petrochemicals, pharmaceutics). The wide range of spatial scales and interactions between the phases in such systems yields a complex flow often coupled with mass and/or heat transfer. These transfer have been widely investigated in the past in an experimental and numerical manners for dilute (1, 2) and dense suspensions (3, 4).

Multi-scale modeling is a numerical approach developed to understand these phenomena from the particle scale (microscale) to process unit (macroscale). An intermediate scale (mesoscale) ranging from 10⁴ to 10⁸ particles is also introduced. …

Cfd-Dem Simulation Of Nanoparticle Agglomerates Fluidization With A Micro- Jet, Daoyin Liu, Berend G. M. Van Wachem, J. Ruud Van Ommen, Robert F. Mudde, Xiaoping Chen

Fluidization XV

Nanoparticles can be fluidized as agglomerates, but for some materials this is cumbersome due to the cohesive nature. Micro-jets are shown to be effective for improving the fluidization in such cases (1). In this study, the mechanisms of micro-jet assistance are investigated by using an adhesive CFD-DEM (Computational Fluid Dynamics – Discrete Element Modelling) model. In previous studies, the complex agglomerates found in a fluidized bed are treated as the discrete elements (2). Here we use the simple agglomerates as the discrete elements, which are the building blocks of the larger complex agglomerates. The collision of the simple agglomerates are …

Segregation Of Equal-Sized Particles Of Different Densities In A Vertically Vibrated Fluidized Bed, E. Cano-Pleite, A. Acosta-Iborra, F. Hernández-Jiménez, T. Tsuji, C. R. Müller

Fluidization XV

Many operations in the chemical and energy-conversion industries rely on the fluidization of heterogeneous materials. During fluidization, particles of different densities can segregate, even if they are of the same size. Segregation is typically an undesired phenomenon, especially in fluidized bed reactors (1). Thus, an understanding of segregation on a fundamental level is paramount to identify effective measures to control it. One approach to control segregation could be the vibration of the bed vessel. However, there is very little literature available concerning the effect of vibration on density-induced segregation dynamics (2).

Thus, this work studies the influence of vibration on …

Reversal Of Gulf Stream Circulation In A Vertically Vibrated Triangular Fluidized Bed, E. Cano-Pleite, A. Acosta-Iborra, F. Hernández-Jiménez, C. R. Müller

Fluidization XV

Vibrated fluidized beds are a process intensification technique consisting in introducing vibratory kinetic energy in a fluidized bed (1). In this work we assess experimentally the effect of vibration on the gulf-stream circulation pattern of particles in a fluidized bed that is of triangular shape. The bed has 0.206 m span and 0.01 m thickness. The base of the bed is composed of two inclined walls, each one forming an angle of 45º with the horizontal. Air was injected through the inclined bed walls to fluidize the bed (see Figure 1a). This gas injection, together with vibration, can make the …

Experimental Study Of Solid Mixing Mechanism In A 2d Fluidized Bed, J. Sánchez-Prieto, A. Soria-Verdugo, L.M. García-Gutiérrez, F. Hernández-Jiménez, F. Suárez-Gómez

Fluidization XV

The main mechanism of solids mixing in bubbling fluidized beds is well understood. When a bubble rises through the bed, it carries a wake of particles to the bed surface. A downflow of solids exists in the region surrounding the rising bubbles, resulting on an overall convective circulation of particles in the axial direction (1).

In this work, a new method to characterize solids mixing in a 2D fluidized bed is developed. This mixing index is able to macroscopically characterize the rate of mixing in a fluidized bed by means of DIA. The mixing index is analogous to the Lacey’s …

Microscopic Modelling Of Capillary Liquid Bridge Force And Volume Repartition For Dem Simulations Of Polydisperse Systems, Alberto Di Renzo, Andrea Lorenti, Francesco P. Di Maio

Fluidization XV

Many fluidization processes like granulation, agglomeration, encapsulation or coating exhibit conditions where liquid bridges form between particles (1), resulting in strong particle-particle interactions at the microscopic scale. DEM and DEM-CFD simulations are able to show how the particle-scale phenomena determine the overall behavior of a wet particulate material in industrial systems.

Description of the capillary interaction between spherical particles in the pendular regime (i.e. with liquid bridges forming on a one-to-one basis) has been long studied and characterized, particularly in the case of spheres of the same size. When polydisperse systems are considered, the formation, interaction force and rupture of …

Recirculating Fluidized Bed Reactor For Chemical-Looping, Raman Sharma, Mines Paristech, Arnaud Delebarre, Babu Alappat

Fluidization XV

Chemical-Looping Combustion (CLC) is an oxy-combustion CO₂ capture technique. CLC involves metal oxides to split the combustion in oxidation and reduction cycles. A wide variety of reactors, single as well as interconnected, have been tested for CLC. These reactor configurations have some operational and process difficulties associated with them. A single Recirculating Fluidized Beds (RCFB) reactor configuration is proposed here for CLC with a feeling that it can overcome some of these problems. RCFB is a spouted fluidized bed with a central riser tube and the outer tube is known as downcomer. A cold model of RCFB reactor was …

Comparison Of Optical Probes And X-Ray Tomography For Bubble Characterization In Fluidized Bed Methanation Reactors, F. Schillinger, S. Maurer, T.J. Schildhauer, S.M.A. Biollaz, E. C. Wagner, R.F. Mudde, J.R. Van Ommen

Fluidization XV

The performance of many fluidized bed reactors strongly depends on the bubble behavior since they influence the mass transfer to the dense phase where the catalyst is present. An example is the methanation in a fluidized bed that allows for conversion of unsaturated hydrocarbons in the gasification gas without catalyst deactivation [1]. The BFB reactor is a very challenging step in the process chain to produce SNG out of biomass as feedstock since next to the bubble behavior a lot of other parameters like temperature, pressure, particle size, attrition of the catalyst, internals, bed height and reactor diameter etc. affect …

Attrition Of Methanol To Olefins Catalyst In A Jet Cup, Mao Ye, Zhongmin Liu, Yinfeng Zhao, Jingai Haoa

Fluidization XV

No abstract provided.

Simulation Of Fuel Particles Motion In A 2d Fluidized Bed Using A Hybrid-Model Considering Wall Friction, L.M. Garcia-Gutierrez, F. Hernández-Jiménez, A. Soria-Verdugo, A. Acosta-Iborra

Fluidization XV

The mixing of fuel particles is a key issue on the performance of fluidized bed reactors. In this work, the motion of a non-reactive fuel particle in a 2D bubbling fluidized bed at ambient conditions is simulated employing a hybrid-model. The hybrid-model, implemented in the code MFIX, simulates the dense and gas phases using a Two-Fluid Model (TFM) while the fuel particles are modeled using a Discrete Element Method (DEM). The importance of the present hybrid-model is that the interaction of the continuum phases with the fuel particles behavior is fully coupled.

In a previous study, Hernández-Jiménez et al. (1) …

Solids Maldistribution In Parallel Cyclones, T. M. Knowlton, John Findlay, Larry P. Hackman, Craig A. Mcknight

Fluidization XV

The amount of solids maldistribution in parallel cyclones was investigated to determine what parameters affected the maldistribution. In many fluidized bed processes with parallel cyclones (as many as 20 in parallel in some cases), it has been noted that unequal erosion (wear) can occur in the cyclones. This results in very short run lengths in order to repair the cyclones with the most wear. This unequal wear has been attributed to unequal solids distribution to the cyclones. In addition to the increased wear, cyclone efficiencies are affected as well.

In the specific concern that generated this study, it was found …

Improved Gas-Solid Mixing And Mass Transfer In A Pulsed Fluidized Bed Of Biomass With Tapered Bottom, Dening Jia, C. Jim Lim, Xiaotao Bi, Shahab Sokhansanj, Atsushi Tsutsumi

Fluidization XV

To improve fluidization quality and mass transfer rate of biomass fluidized beds with pulsed gas flow, an existing fluidized bed with rectangular cross-section area was modified with the insertion of a tapered bottom section such that dead zones observed in the original design could be eliminated. Batch drying tests were performed as an indirect indicator of gas-solid contact efficiency and mass transfer performance. Compared to the original design, biomass particles could be fluidized at a wider range of gas pulsation frequencies with significantly reduced channeling and gas bypassing in the new tapered design. Faster drying and thus improved mass transfer …