Engineering Commons^™

Modeling Of Turbulent Drag Reducing Fluid Flow, Mohamed Samir Fouda, Mohamed M. Awad, Lotfy H. Rabie

Mansoura Engineering Journal

In the present study, a standard eddy viscosity turbulence model for Newtonian fluids has been developed to predict the drag reduction and the mean velocity profile of drag reducing fluids. In addition, this model is an extension of FENE-P eddy viscosity model for viscoelastic fluids without using any additional constitutive equation.

In this paper, the first section is concerned with developing a new correlation for the eddy viscosity equation, which depends on the flow and rheological parameters, based on the Direct Numerical Simulation (DNS) data. For this purpose, a User Defined Function (UDF) was interpreted to Fluent 16.1 solver to …

System, Device, And Method For Determination Of Intraocular Pressure, Jeffrey Todd Hastings, E. Britt Brockman, Ingrid L. St. Omer, John C. Wright

Electrical and Computer Engineering Faculty Patents

A system for determination of intraocular pressure includes: an intraocular pressure sensor; a light source illuminating the sensor with one or more wavelengths of light; and a detector that measures emitted light from the sensor. The sensor includes a substrate member, a spacer member, and a flexible membrane, which define a sealed cavity. The flexible membrane moves in response to intraocular pressure changes. A device for measuring intraocular pressure includes: the sensor; an anchoring member attached to the sensor for immobilizing the sensor in an eye; and a protective member attached to the anchoring member and covering the sensor to …

Polyimide/Silicon Dioxide Nanocomposites As Dielectrics For Helium-Cooled High-Temperature Superconducting Cables, Harrison Michael Hones

Theses and Dissertations

In this thesis, polyimide (PI) and silicon dioxide (SiO2) were combined in the form of a nanocomposite for use as a dielectric on helium-cooled high-temperature superconducting (HTS) cables. Further, a cryogenic chamber was designed with the intent of cooling samples to 40 K for dielectric and thermal contraction testing. Composites were created through an in situ process which resulted in nanoparticle formation within the host matrix. Samples were tested for dielectric strength at room temperature (300 K) as well as cryogenic temperature (92 K) using liquid nitrogen as the coolant. Composite samples tested at 300 K averaged a dielectric strength …

A Mathematical Model To Predict The Porosity Of Locally Electrodeposited Nickel Under Pulsed Voltage Conditions, Abishek Balsamy Kamaraj, Murali Sundaram

Industrial & Manufacturing Engineering Presentations And Conference Materials

Metal parts manufactured with engineered porosity offer advantages over traditional parts as they have excellent specific mechanical properties at a lower weight. This is especially of interest in the aerospace and automobile industries. Additive manufacturing allows for creating parts with computer aided design (CAD) modeled lattice structures that offer lightweight parts. However, there is a need for porous structures at the micron scale (<50 µm) which cannot be achieved in a controlled manner using traditional powder-bed based metal additive manufacturing processes. Electrochemical Additive Manufacturing (ECAM) is a novel non-thermal metal additive manufacturing process capable of producing metal 3D parts with engineered porosity at the micron scale. There is a lack of understanding of the cause of porosity and controlling the porosity generated in the parts created using this process. In this paper, the effects of the electrical parameters of deposition, such as the pulse duty cycle and pulse frequency during electrodeposition, on the porosity of the manufactured parts were mathematically modeled. The model predicts that higher frequency electrodeposition leads to more porous structures. The model developed in this study can be used to predict the process parameters needed to deposit nickel microstructures with desired levels of porosity between 20 and 55 %. These model predictions were also validated by experiments. Two mechanisms for the cause of porosity in the deposits were identified. The diffusion-limited deposition phenomenon causing a lack of availability of cations results in larger sized pores and hollow structures to form on the part. The crystal growth and the nucleation process cause micron-scale pores.

Implementation Of Sr Flip-Flop Based Puf On Fpga For Hardware Security, Sai Praneeth Sagi

USF Tampa Graduate Theses and Dissertations

Physical Unclonable Functions (PUF) are used for authentication and key generation to obtain a unique signature and are widely used in hardware security applications. In this work, we propose Set-Reset Flip-flop (SRFF) based PUF for FPGAs. We exploit the race around condition of the SRFF to obtain a one-bit signature output which is a function of feedback path delays. In deep sub-micron technology node, delay variations on an FPGA device are significant due to manufacturing process variations. Thus, an SRFF output value is a function of its location on the FPGA device. We implement registers of various bit widths and …

Bijels Made By Solvent Transfer Induced Phase Separation: Formation Principles And Transport, Stephen Boakye-Ansah

Theses and Dissertations

Bijels are made of non-equilibrium particle-stabilized emulsions with a bicontinuous arrangement of the constituent fluid phases. They spontaneously form through arrested spinodal decomposition in mixtures of partially miscible liquids and neutrally wetting colloidal particles. Soon after their discovery over 10 years ago, Prof. Mike Cates, Lucasian Professor of Mathematics, predicted their future use as continuously operated cross-flow reactors for chemical reactions between immiscible reactants.

Towards this goal, work in this thesis focuses on designing bijels via Solvent Transfer Induced Phase Separation (STrIPS) for microfluidic transport applications. Structure-function relationships of STrIPS bijels stabilized by silane functionalized nanoparticles are developed. In-situ surfactant …

The Effect Of The Top Soil Layer On Moisture And Evaporation Dynamics, Zhen Li, Jan Vanderborght, Kathleen M. Smits

Civil Engineering Faculty Publications - Archive

Understanding the effect of the top soil layer on surface evaporation and water distribution is critical to modeling hydrological systems. However, the dependency of near-surface soil moisture and fluxes on layering characteristics remains unclear. To address this uncertainty, we investigate how the arrangement of soil horizons affects the evaporation and soil moisture, specifically, the near-surface soil moisture, through the combination of numerical simulations and evaporation experiments. The characteristics of fluxes and moisture from different soil profiles are then used to understand the soil layering conditions. Results show that the top soil layer can significantly affect the evolution of soil moisture …

Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff

Faculty Publications

Biodiesel offers several environmental benefits and improvements to some fuel performance properties, but its poor oxidative stability has been a major concern. Currently, the accepted practice to improve biodiesel oxidative stability is the addition of antioxidants; numerous antioxidants have been studied but their effectiveness in inhibiting biodiesel oxidation is difficult to predict due to variation with resonance stability, solubility, reactivity, and volatility. To improve prediction efforts, this study explored the Rapid Small-Scale Oxidation Test (RSSOT) as a means to investigate how biodiesel oxidation is affected by antioxidant concentration and temperature, and compared its results with the oxidative stability index test. …

Characterization And Modeling Of Surface Roughness And Burr Formation In Slot Milling Of Polycarbonate, David Adeniji, Julius M. Schoop, Shehan Gunawardena, Craig Hanson, Muhammad Jahan

Mechanical Engineering Faculty Publications

Thermoplastic materials hold great promise for next-generation engineered and sustainable plastics and composites. However, due to their thermoplastic nature and viscoplastic material response, it is difficult to predict the properties of surfaces generated by machining. This is especially problematic in micro-channel machining, where burr formation and excessive surface roughness lead to poor component-surface integrity. This study attempts to model the influence of size effects, which occur due to the finite sharpness of any cutting tool, on surface finish and burr formation during micro-milling of an important thermoplastic material, polycarbonate. Experimental results show that the depth of cut does not affect …

Evaluating And Improving The Seu Reliability Of Artificial Neural Networks Implemented In Sram-Based Fpgas With Tmr, Brittany Michelle Wilson

Theses and Dissertations

Artificial neural networks (ANNs) are used in many types of computing applications. Traditionally, ANNs have been implemented in software, executing on CPUs and even GPUs, which capitalize on the parallelizable nature of ANNs. More recently, FPGAs have become a target platform for ANN implementations due to their relatively low cost, low power, and flexibility. Some safety-critical applications could benefit from ANNs, but these applications require a certain level of reliability. SRAM-based FPGAs are sensitive to single-event upsets (SEUs), which can lead to faults and errors in execution. However there are techniques that can mask such SEUs and thereby improve the …

Dynamic Reconfigurable Real-Time Video Processing Pipelines On Sram-Based Fpgas, Andrew Elbert Wilson

Theses and Dissertations

For applications such as live video processing, there is a high demand for high performance and low latency solutions. The configurable logic in FPGAs allows for custom hardware to be tailored to a specific video application. These FPGA designs require technical expertise and lengthy implementation times by vendor tools for each unique solution. This thesis presents a dynamically configurable topology as an FPGA overlay to deploy custom hardware processing pipelines during run-time by utilizing dynamic partial reconfiguration. Within the FPGA overlay, a configurable topology with a routable switch allows video streams to be copied and mixed to create complex data …

Feasibility Of Tempo-Functionalized Imidazolium, Ammonium And Pyridinium Salts As Redox-Active Carriers In Ethaline Deep Eutectic Solvent For Energy Storage, Brian Chen, Nicholas Sinclair, Jesse Wainright, Burcu E. Gurkan

Faculty Scholarship

The discovery of electrolytes that have low vapor pressures and high solubility towards redox active species with an ability to undergo multiple electron transfer reactions is a challenge to realize in large-scale energy storage. Herein, we investigate the feasibility of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) derived halide salts as redox active species in ethaline (1 : 2 ethylene glycol : choline chloride), a deep eutectic solvent (DES). Hydrogen bonding and electrostatic interactions achieved by the functionalization of TEMPO are shown to improve solubility in ethaline. This is the first study evaluating the physical properties and electrochemical behavior of the newly synthesized TEMPO-salts in …

Developing A Mobile Application‐Based Particle Image Velocimetry Tool For Enhanced Teaching And Learning In Fluid Mechanics: A Design‐Based Research Approach, Angela L. Minichiello, David Armijo, Sarbajit Mukherjee, Lori M. Caldwell, Vladimir Kulyukin, Tadd T. Truscott, Jack Elliott, Aditya Bhouraskar

Engineering Education Faculty Publications

A robust and intuitive understanding of fluid mechanics—the applied science of fluid motion—is foundational within many engineering disciplines, including aerospace, chemical, civil, mechanical, naval, and ocean engineering. In‐depth knowledge of fluid mechanics is critical to safe and economical design of engineering applications employed globally everyday, such as automobiles, aircraft, and sea craft, and to meeting global 21st century engineering challenges, such as developing renewable energy sources, providing access to clean water, managing the environmental nitrogen cycle, and improving urban infrastructure. Despite the fundamental nature of fluid mechanics within the broader undergraduate engineering curriculum, students often characterize courses in fluid mechanics …

Modeling And Simulation Of A 20kv Ultra-Fast Dc Circuit Breaker For Electric Shipboard Applications, Trevor Arvin, Jiangbiao He, Nathan Weise, Tiefu Zhao

Electrical and Computer Engineering Faculty Research and Publications

A novel hybrid circuit breaker for medium voltage dc (MVDC) electric shipboard power systems is proposed. The breaker combines the benefits of the efficiency of a mechanical breaker and the interruption speed of a solid-state breaker. The proposed breaker utilizes a fast-ramping current source with a fast-actuating vacuum interrupter (VI) to provided ultra-fast response time and high on-state efficiency. During normal operation, nominal load current flows through the vacuum interrupter in the main conduction branch, providing a low-resistance path with negligible losses. During a fault, a current zero crossing is achieved by the use of a controllable resonant current source …

Development Of An Organic Processor Assembly (Opa) For Sustainable Resource Recovery To Enable Long-Duration, Deep-Space Human Exploration (Loddshe), Talon James Bullard

USF Tampa Graduate Theses and Dissertations

Long-Duration, Deep-Space Human Exploration (LoDDSHE) missions demand robust and reliable technologies to ensure crew health, safety, and mission success. In situ food production will become essential for these missions for crew nutrition, morale, and in the event of delays or failures. At a current estimated cost $10,000/lb, mass and volume limitations will restrict necessary resources. For an anticipated thirty-month mission to Mars, these costs will increase due to more frequent resupply shipments and lengthened transit times, creating additional financial and logistical challenges (Pickett et al., 2019). Increased resource and waste recovery to achieve nearly closed-loop systems will mitigate many of …

Investigation Of Deformation Induced Micro To Macro Scale Surface Roughness, Ayotunde Olayinka, William J. Emblom, Scott W. Wagner, Michael Khonsari, Ali Haghshenas

Michigan Tech Publications, Part 1

In the present work the relationship between deformation and deformation induced surface roughness of 100 micron thick annealed AISI 304 stainless steel was investigated at the meso scale. This work is a continuation of the previous work by the authors where roughness values were determined at the apex of the bulge test samples at micro scale. The apex is believed to be the region of highest stress and strain in a typical bulge process in a circular die. The material was deformed using a biaxial bulge test through hydraulic fluid pressure. The strains on the workpieces were measured with respect …

Student Responses To Active Learning Strategies: A Comparison Between Project-Based And Traditional Engineering Programs, Elizabeth Pluskwik, Yuezhou Wang

Integrated Engineering Department Publications

Prior research has shown that active learning strategies in engineering education improve student learning, motivation, and retention in STEM disciplines. Yet, instructors are often hesitant to use active learning and other non-lecture strategies due to challenges from students who are resistant to engaging in these methods. Prior research has suggested strategies that can be used to mitigate student resistance to active learning, yet many faculty members have not yet implemented active learning into their engineering education courses. The global demand for entrepreneurially-minded engineers and the rapid growth of engineering programs embracing this mindset increases the need for actionable resources and …

Kinematic Analysis And Trajectory Planning Of Biped Robots, Akash Ravindra, Mohit Motwani, Rishi Kavi

Manipal Institute of Technology, Manipal Theses and Dissertations

A bipedal robot is a human-inspired self-balancing mechanism with two limbs. Our study is confined to a 6DOF spatial mechanism that mirrors the walking style of humans to carry out complex tasks. In the development of the walking trajectory of the biped, forward and inverse kinematics of the biped’s links become crucial to maintain balance and an optimal gait. There can be random errors introduced to the physical system due to mechanical inaccuracies such as joint clearance and link tolerance. This work presents an approach to estimate and quantify the errors due to the inaccuracy. This study is followed by …

Influence Of Elements Of Irrigation Equipment On Irrigation Erosion, M.M. Sarimsakov, O.S. Abdisamatov, Z.T. Umarova

Irrigation and Melioration

Irrigation erosion is a process that has a significant negative impact on agricultural production, which leads to a sharp decrease in soil fertility and productivity. The costs associated with growing crops will increase. Today, more than 720,000 irrigated lands in the country suffer from irrigation erosion. Studies have shown that in typical gray soils with a slope of more than 0.30, intensive irrigation of apple orchards leaches 24.6 tons of soil particles per hectare per season. Improved irrigation, that is, a decrease in the leaching of soil particles during irrigation using transverse barriers, was achieved by 6–12%. Irrigation reduces the …

Research Of Water Flow Motion In The Channel Of Amu-Bukhara Machine Channel, D.R. Bazarov, F. Artikbekova, M.P. Tashkhanova, B.M. Norkulov

Irrigation and Melioration

The article considers a numerical study of the movement of a water stream in the channel of the Amu Bukhara Machine Channel (ABMK). Water intake to the inlet canal is carried out from the Amu Darya river in a damless manner, therefore, ensuring the flow of clarified water into the anterior chambers of pumping stations is an urgent task. According to the developed model, consisting of hydrodynamic equations based on the laws of conservation of momentum and mass, data on the dynamics of velocities in the channel of the supply channel ABMK are obtained and zones of uneven flow in …

Irrigation Value The Mechanical Composition River Springs, A.M. Arifjanov, L.N. Samiev, F.K. Babajanov

Irrigation and Melioration

The article studies the influence of the fractional composition of river sediments on the soil structure of irrigated lands and on the process of soil formation. According to surveys in the Mirishkor canal, sediments formed in the river are distinguished by the distribution type in the main canal. The fractional composition of sediments mainly consists of particles of fine sand (0.1-0.05 mm) and coarse dust (0.05-0.001 mm).According to the results of surveys, by studying the mechanical composition of sediment in the channel, it will be possible to observe changes in the amount of composition, such as N-NH4, P2O5, K2O chemicals. …

Monitoring System For Electricity Consumption At Pumping Stations, N. Ikramov, T. Majidov, A. Mukhammadjonov

Irrigation and Melioration

Currently, in Uzbekistan, of 4.3 million hectares of irrigated land, 2.3 million hectares are provided with water supplied by pumping stations that are on the balance of the Ministry of water management of the Republic of Uzbekistan. In total, 1693 pumping stations with 5301 pumping units are operated, and the number of pumping stations ' personnel is about 16,000 people. The total capacity of these pumping stations is about 7000 m3/s. the Total annual energy consumption of these pumping stations is about 8.0 billion kW·h or about 12.5% of the annual electricity generation of the entire energy sector of Uzbekistan. …

Irrigation Value The Mechanical Composition River Spring The Effect Of The Inhomogeneity Of Elastic Medium On The Initiation Of Resonant Waves Under Moving Load, S.A. Abdukadirov, Z.S. Shаdmаnova, B.Sh. Yuldoshev

Irrigation and Melioration

investigated. The waveguide properties of the system are preliminarily studied. The multiple roots of the dispersion equations are revealed and the critical load velocities leading to the formation of resonance processes are determined. The solutions of the dispersion equations make it possible to determine the additional critical velocities in the mid-wave spectrum depending on the structure parameters. For simple models, analytical solutions of the development of resonance processes are obtained that are asymptotically correct for relatively large values of time. The computer simulations allow us to analyze the quantitative features of the process over the entire time period of the …

Substantiation Of Sprayers Installed To A Universal Mounted Sprayer, D. Dzhuraev, M.S. Halilov, S.M. Badalov, I.Zh. Toirov, A.E. Urishev

Irrigation and Melioration

The article presents the results of theoretical and experimental studies on the creation of primary sprayers for sprayers. The flow diagrams of the atomizers that were produced on the territory of the former Soviet Union are given. Currently, various types of spray guns are manufactured in America, Germany, France, Italy, Bulgaria and other countries. Based on the set requirements for sprayers, to ensure fluid flow and spraying when deployed 90-110 degrees on a plane, a slotted sprayer is selected - manufacturer Lechler of the brand ST-110-05 Germany, for installation on a universal mounted sprayer. The results of fluid flow by …

Technological Features Of Moistening Of Technical Seeds, O. Matchanov, B. Tuxtamishev

Irrigation and Melioration

This article describes the technological features of the reduction of technical varieties of cotton. Requirements for technical seeds in the processing of raw cotton are technical specifications and quality indicators. Seeds of technical cotton with quality indicators and adapted technical seeds must meet the requirements of technical conditions. The technical need for coated seeds should correspond to technical characteristics, such as reducing production costs, reducing moisture, long-term storage, improving quality, thermal conductivity, aerodynamic resistance, and heat resistance. From the point of view of heat treatment of seeds, parameters taking into account their thermophysical properties should be used to justify the …

Regulations Of Hydraulic Resistance Of Machine Channels Of Pumping Stations, D.R. Bazarov, B.R. Uralov, M.P. Tashkhanova

Irrigation and Melioration

The paper considers the general equation of fluid motion in the channels and the functional dependences of the hydraulic friction coefficient on the Reynolds number, relative roughness, and on the shape of the live section of the channel. Resistance formulas are given for the simplest cross-sectional shapes of channels and for channels with a more complex cross-sectional shape. To take into account the effect (on the pressure loss) of the channel cross-sectional shape and the presence of a flow with a free surface in it, additional correction factors are introduced (using the hydraulic radius concept) and be clarified as a …

Studying The Movement Of Crop Drined Seeds Of Cottage On A Slope Tray In A Protective Machine, R.K. Djamolov, A.A. Akrаmov, K. Djamolov

Irrigation and Melioration

The article presents the results of a theoretical study of the movement of pubescent cotton seeds along an inclined guide in a pickling machine. Equations are obtained that describe the movement of the seed along the inclined tray of the dresser. A formula is derived for determining the time of movement of the seed on an inclined one to the dressing agent. A plot of the change in the speed of the seed in the tray on the change in the angle of inclination and on the value of the movement of the seed. To increase the feed rate of …

Modernization Of Functions Of Management Of Land Use In The Conditions Of Innovative Economy, Sh.K. Narbaev

Irrigation and Melioration

Land use management, as a complex material-abstract system, is carried out through a number of its functions. The article provides an analysis of the functions of land management, improved the content of some functions and introduced additional new functions in the context of the development of an innovative economy. It is noted that improving the management system will increase the efficiency of land use, improve their environmental status, preserve landscape ecosystems based on the accelerated development of innovative activities. New land management functions are recommended: innovative land use development, territory development, land use technical support, remote study of land properties …

Combined Installation Photo Thermal Battery - Electric Water Heater To Provide Electricity And Water To Rural Households, R.A. Muminov, M.N. Tursunov, Х. Sabirov, U.R. Kholov, Т.Z. Аkhtamov, М. Eshmuradova

Irrigation and Melioration

The article presents the experimental results of the study of the parameters of a combined installation photo thermal battery – electric heater, used to provide electric energy and water to rural households. Photo thermal battery is made on the basis of photovoltaic batteries of crystalline silicon with an efficiency of ~ 20 %. Cellular polycarbonate was used as a heat sink. When creating the KU based on photo thermal battery EVN, modern efficient batteries, controllers, inverters and consumers of electric energy were used, and Ariston was chosen as the EVN. KU is adapted to climatic conditions, effectively and reliably provides …

Modeling The Movement Of A Heap In A Dielectric Sorting Device For Alfalfa Seeds, A. Lee, Z. Sharipov, M.N. Sattarov

Irrigation and Melioration

This article presents a theoretical study of modeling the movement of a mixture in a dielectric sorting plant for alfalfa seeds. Theoretical studies were carried out using the general laws of mechanics and mathematical modeling of alfalfa seeds, taking into account their physical and mechanical properties. The results of a theoretical study on modeling the detachment conditions of alfalfa seed heap particles and particle dynamics along the casing and pitched boards of a dielectric sorting device are presented. The differential equation with the initial conditions was solved by numerical methods of "Runge-Kutta-Felberg" with automatic step selection. The components of a …