Mechanical Engineering Commons^™

Direct Numerical Simulation Of Transverse Ripples: 1. Pattern Initiation And Bedform Interactions, ‪Nadim Zgheib, J. J. Fedele, D. C. J. D. Hoyal, M. M. Perillo, S. Balachandar

Mechanical Engineering Faculty Publications

We present results of coupled direct numerical simulations between flow and a deformable bed in a horizontally periodic, turbulent open channel at a shear Reynolds number of Reτ = 180. The feedback between the temporally and spatially evolving bed and the flow is enforced via the immersed boundary method. Using the near-bed flow field, we provide evidence on the role of locally intense near-bed vortical structures during the early stages of bed formation, from the emergence of quasi-streamwise streaks to the formation of incipient bedform crestlines. Additionally, we take a new look at a number of defect-related bedform interactions, …

Direct Numerical Simulation Of Transverse Ripples: 2. Self-Similarity, Bedform Coarsening, And Effect Of Neighboring Structures, ‪Nadim Zgheib, J. J. Fedele, D. C. J. D. Hoyal, M. M. Perillo, S. Balachandar

Mechanical Engineering Faculty Publications

Coupled bed-flow direct numerical simulations investigating the early stages of pattern formation and bedform (ripple) interactions were examined in a previous paper (Part 1), making use of the resolved flow field. In this paper (Part 2), we compare our results to published experimental data and provide an extensive quantitative analysis of the bed using spectral analysis and two-point correlations. The effect of the mobile rippled bed on the flow structure and turbulence is investigated locally (at specific streamwise locations) and over the entire computational domain. We show that developing ripples attain a self-similar profile in both the shape and the …

A Method For Characterizing Essential Tremor From The Shoulder To The Wrist, Daniel W. Geiger, Dennis Eggett, Steven K. Charles

Faculty Publications

Background

Despite the pervasive and devastating effect of Essential Tremor (ET), the distribution of ET throughout the upper limb is unknown. We developed a method for characterizing the distribution of ET and performed a preliminary characterization in a small number of subjects with ET.

Methods

Using orientation sensors and inverse kinematics, we measured tremor in each of the seven major degrees of freedom (DOF) from the shoulder to the wrist while ten patients with mild ET assumed 16 different postures. We described the tremor in each DOF in terms of power spectral density measures and investigated how tremor varied between …

Some Insights Into The Migration Of Double Imaginary Roots Under Small Deviation Of Two Parameters, Dina Alina Irofti, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper studies the migration of double imaginary roots of the systems’ characteristic equation when two parameters are subjected to small deviations. The proposed approach covers a wide range of models. Under the least degeneracy assumptions, we found that the local stability crossing curve has a cusp at the point that corresponds to the double root, and it divides the neighborhood of this point into an S-sector and a G-sector. When the parameters move into the G-sector, one of the roots moves to the right halfplane, and the other moves to the left half-plane. When the parameters move into the …

Assessing Spacing Impact On Coherent Features In A Wind Turbine Array Boundary Layer, Naseem Ali, Nicholas Hamilton, Dominic Delucia, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

As wind farms become larger, the spacing between turbines becomes a significant design consideration that can impose serious economic constraints. To investigate the turbulent flow structures in a 4 x 3 Cartesian wind turbine array boundary layer (WTABL), a wind tunnel experiment was carried out parameterizing the streamwise and spanwise wind turbine spacing. Four cases are chosen spacing turbines by 6 or 3D in the streamwise direction, and 3 or 1:5D in the spanwise direction, where D = 12 cm is the rotor diameter. Data are obtained experimentally using stereo particle image velocimetry. Mean streamwise velocity showed maximum …

Ureteral Tunnel Length Versus Ureteral Orifice Configuration In The Determination Of Ureterovesical Junction Competence: A Computer Simulation Model, Carlos A. Villanueva, J. Tong, Carl A. Nelson, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Introduction The long-held belief that a ureteral re-implant tunnel should be five times the diameter of the ureter, as proposed by Paquin in 1959, ignores the effect of the orifice on the occurrence of reflux. In 1969, Lyon proposed that the shape of the ureteral orifice (UO) is more important than the intravesical tunnel. However, both theories missed quantitative evidence from principles of physics. The goal of the current study was to test Lyon’s theory through numerical models (i.e. to quantify the sensitivity of ureterovesical junction (UVJ) competence to intravesical tunnel length and to the UO).

Materials and methods The …

Eigenstrain As A Mechanical Set-Point Of Cells, Shengmao Lin, Marsha C. Lampi, Cynthia A. Reinhart-King, Gary C.P. Tsui, Jian Wang, Carl A. Nelson, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Cell contraction regulates how cells sense their mechanical environment. We sought to identify the set-point of cell contraction, also referred to as tensional homeostasis. In this work, bovine aortic endothelial cells (BAECs), cultured on substrates with different stiffness, were characterized using traction force microscopy (TFM). Numerical models were developed to provide insights into the mechanics of cell–substrate interactions. Cell contraction was modeled as eigenstrain which could induce isometric cell contraction without external forces. The predicted traction stresses matched well with TFM measurements. Furthermore, our numerical model provided cell stress and displacement maps for inspecting the fundamental regulating mechanism of cell …

Propeller Design Requirements For Quadcopters Utilizing Variable Pitch Propellers, Ian R. Mcandrew, Elena Navarro, Ken Witcher

Publications

Unmanned aerial vehicles, UAV, has increases in the drastically in these past several years since their costs reduced. This research is based and built upon previous research presented in a conference. With the advent of commercial Quadcopters, four propeller systems, are used, being designed and used to operate the advantages of both flight and hovering. The basic design of their propeller blades has not evolved from the early days of manned flight when wooden fixed blades were used. In this paper that expands upon previous findings and discussions it explores the historical developments. Furthermore, how the expansion and reduction in …

Improving And Predicting The Effectiveness Of Dispersed, Multi-Disciplinary Design Teams, Matthew Oliver Wald

Theses and Dissertations

The use of dispersed (virtual) teams is growing rapidly in the engineering profession. To help prepare students for work in this type of industry, university engineering courses are requiring students to work in teams. Industry leaders and university faculty are interested in improving and measuring the performance of these distributed teams. Surveys, interviews, and observations from the AerosPACE Partners for the Advancement of Collaborative Engineering (AerosPACE) capstone design course are examined to demonstrate how different collaboration tools can be used to best enhance a distributed design team's effectiveness. Collaboration tools to which distributed design teams should give extra consideration at …

Electric Vehicle Interaction At The Electrical Circuit Level, Florida Solar Energy Center, Shawyun Sariri

FSEC Energy Research Center®

A large growth in energy demand has increased renewable energy penetration into existing power grid infrastructures, as well as spurring increased research into demand response programs. But before implementing an efficient demand response program, it is first necessary to understand the power usage behaviors of a consumer. This paper presents a real-time data acquisition system for the collection and storage of power data that will allow the study of demand response in an urban area, which can be applied to the efficient use of electric vehicle supply equipment (EVSE). Demand response programs are an ideal alternative to costly energy storage …

Opty: Software For Trajectory Optimization And Parameter Identification Using Direct Collocation, Jason K. Moore, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

opty is a tool for describing and solving trajectory optimization and parameter identification problems based on symbolic descriptions of ordinary differential equations and differential algebraic equations that describe a dynamical system. The motivation for its development resides in the need to solve optimal control problems of biomechanical systems. The target audience is engineers and scientists interested in solving nonlinear optimal control and parameter identification problems with minimal computational overhead.

Electrospun Fibers As A Dressing Material For Drug And Biological Agent Delivery In Wound Healing Applications, Mulugeta Gizaw, Jeffrey Thompson, Addison Faglie, Shih-Yu L Lee, Pierre Neunenschwander, Shih-Feng Chou

Mechanical Engineering Faculty Publications and Presentations

Wound healing is a complex tissue regeneration process that promotes the growth of new tissue to provide the body with the necessary barrier from the outside environment. In the class of non-healing wounds, diabetic wounds, and ulcers, dressing materials that are available clinically (e.g., gels and creams) have demonstrated only a slow improvement with current available technologies. Among all available current technologies, electrospun fibers exhibit several characteristics that may provide novel replacement dressing materials for the above-mentioned wounds. Therefore, in this review, we focus on recent achievements in electrospun drug-eluting fibers for wound healing applications. In particular, we review drug …

Microfluidic Device And Method Using Double Anodic Bonding, Stephen Forrest, Gregory Mcgraw, Siddharth Harikrishna Mohan, Diane Peters

Mechanical Engineering Patents

A microfluidic device for use with a microfluidic delivery system, such as an organic vapor jet printing device, includes a glass layer that is directly bonded to a microfabricated die and a metal plate via a double anodic bond. The double anodic bond is formed by forming a first anodic bond at an interface of the microfabricated die and the glass layer, and forming a second anodic bond at an interface of the metal plate and the glass layer, where the second anodic bond is formed using a voltage that is lower than the voltage used to form the first …

A 2-D Finite Element Modeling And Simulation Of 3-Roll Forming, Wenbo Zhao

LSU Master's Theses

Medium to large diameter carbon steel pipes are widely used in various applications such as gas and fluid transportation, tunnels construction and building construction. Based on manufacturing techniques and characteristics, they are mainly categorized into three categories: Seamless pipe, Butt-welded pipe and Spiral pipe. The forming of butt-welded and spiral pipe is often performed by a technique called 3-roller bending. While traditional trial-and-error method is costly, the geometry complexity, along with material nonlinearity makes exact theoretical analysis difficult unless heavy simplified assumptions are made. While the forming parameters in the 3-roller forming process of butt-welded pipe has been studied in …

Peri-Elastodynamic Simulations Of Guided Ultrasonic Lamb Waves In Smart Structure With Surface Mounted Pzt, Subir Patra, Hossain Ahmed, Sourav Banerjee

Faculty Publications

Peridynamic based elastodynamic computation tool named Peri-elastodynamics is proposed herein to simulate the three-dimensional (3D) Lamb wave modes in materials for the first time. Peri-elastodynamics is a nonlocal meshless approach which is a scale-independent generalized technique to visualize the acoustic and ultrasonic waves in plate-like structure, micro-electro-mechanical systems (MEMS) and nanodevices for their respective characterization. In this article, the characteristics of the fundamental Lamb wave modes are simulated in a sample plate-like structure. Lamb wave modes are generated using a surface mounted piezoelectric (PZT) transducer which is actuated from the top surface. The proposed generalized Peri-elastodynamics method is not only …

Mechanical And Electrical Characterization Of Carbon Fiber/Bucky Paper/Zinc Oxide Hybrid Composites, Suma Ayyagari, Marwan Al-Haik, Virginie Rollin

Publications

The quest for multifunctional carbon fiber reinforced composites (CFRPs) expedited the use of several nano reinforcements such as zinc oxide nanorods (ZnO) and carbon nanotubes (CNTs). Zinc oxide is a semi-conductor with good piezoelectric and pyroelectric properties. These properties could be transmitted to CFRPs when a nanophase of ZnO is embedded within CFRPs. In lieu of ZnO nanorods, Bucky paper comprising mat of CNTs could be sandwiched in-between composite laminae to construct a functionally graded composite with enhanced electrical conductivities. In this study, different configurations of hybrid composites based on carbon fibers with different combinations of ZnO nanorods and Bucky …

Shoe–Floor Interactions In Human Walking With Slips: Modeling And Experiments, Mitja Trkov, Jingang Yi, Tao Liu, Kang Li

Henry M. Rowan College of Engineering Departmental Research

Shoe–floor interactions play a crucial role in determining the possibility of potential slip and fall during human walking. Biomechanical and tribological parameters influence the friction characteristics between the shoe sole and the floor and the existing work mainly focus on experimental studies. In this paper, we present modeling, analysis, and experiments to understand slip and force distributions between the shoe sole and floor surface during human walking. We present results for both soft and hard sole material. The computational approaches for slip and friction force distributions are presented using a spring-beam networks model. The model predictions match the experimentally observed …

Stress Analysis Of Embedded Devices Under Thermal Cycling, Sadhana Radhakrishnan

Dissertations and Theses

Embedded active and passive devices has been increasingly used by in order to integrate more functions inside the same or smaller size device and to meet the need for better electrical performance of the component assemblies.

Solder joints have been used in the electronic industry as both structural and electrical interconnections between electronic packages and printed circuit boards (PCB). When solder joints are under thermal cyclic loading, mismatch in coefficients of thermal expansion (CTE) between the printed circuit boards and the solder balls creates thermal strains and stresses on the joints, which may finally result in cracking. Consequently, the mechanical …

Field And Laboratory Testing Of Approaches To Smart Whole-House Mechanical Ventilation Control, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

Whole-house mechanical ventilation is a critical component to a comprehensive strategy for good indoor air quality (IAQ). However, due to lack of integration with standard heating and cooling systems, and perceptions from a portion of the homebuilding industry about risks related to increased energy use, increased cost, and decreased comfort, voluntary and code-required adoption varies amongst regions. Smart ventilation controls (SVC) balance energy consumption, comfort, and IAQ by optimizing mechanical ventilation operation to reduce the heating and/or cooling loads, improve management of indoor moisture, and maintain IAQ equivalence according to ASHRAE 62.2.Suggested Citation:Martin, E.; Fernaughty, K.; Parker, D.; Lubliner, M.; …

Modeling Multicomponent Fuel Droplet Vaporization With Finite Liquid Diffusivity Using Coupled Algebraic-Dqmom With Delumping, Alanna Y. Cooney, Simcha L. Singer

Mechanical Engineering Faculty Research and Publications

Multicomponent fuel droplet vaporization models for use in combustion CFD codes often prioritize computational efficiency over model complexity. This leads to oversimplifying assumptions such as single component droplets or infinite liquid diffusivity. The previously developed Direct Quadrature Method of Moments (DQMoM) with delumping model demonstrated a computationally efficient and accurate approach to solve for every discrete species in a well-mixed vaporizing multicomponent droplet. To expand the method to less restrictive cases, a new solution technique is presented called the Coupled Algebraic-Direct Quadrature Method of Moments (CA-DQMoM). In contrast to previous moment methods for droplet vaporization, CA-DQMoM solves for the evolution …

High-Throughput Production With Improved Functionality And Graphitization Of Carbon Fine Fibers Developed From Sodium Chloride-Polyacrylonitrile Precursors, Mandana Akia, Lee Cremar, Manuel Seas, Jahaziel Villarreal, Mataz Alcoutlabi, Karen Lozano

Mechanical Engineering Faculty Publications

Fine polyacrylonitrile (PAN) fibers were produced through a scalable centrifugal spinning process. Sodium chloride (NaCl) was added to the PAN-dimethylformamide solution to decrease the surface tension and consequently promote a decrease in fiber diameter while increasing the fiber output. The fiber preparation process involved the centrifugal spinning of the PAN-based solution; developed fibers were stabilized in air at 240°C followed by carbonization at 800°C under a Nitrogen atmosphere. The addition of sodium chloride to the PAN solution led to a 37% decrease in the carbon fiber diameter. The carbon fibers were analyzed by scanning electron microcopy, transmission electron microscopy (TEM), …

High-Throughput Production With Improved Functionality And Graphitization Of Carbon Fine Fibers Developed From Sodium Chloride-Polyacrylonitrile Precursors, Mandana Akia, Lee Cremar, Manuel Seas, Jahaziel Villarreal, Alejandra Valdez, Mataz Alcoutlabi, Karen Lozano

Mechanical Engineering Faculty Publications

Fine polyacrylonitrile (PAN) fibers were produced through a scalable centrifugal spinning process. Sodium chloride (NaCl) was added to the PAN-dimethylformamide solution to decrease the surface tension and consequently promote a decrease in fiber diameter while increasing the fiber output. The fiber preparation process involved the centrifugal spinning of the PAN-based solution; developed fibers were stabilized in air at 240°C followed by carbonization at 800°C under a Nitrogen atmosphere. The addition of sodium chloride to the PAN solution led to a 37% decrease in the carbon fiber diameter. The carbon fibers were analyzed by scanning electron microcopy, transmission electron microscopy (TEM), …

Nano-Graphene Oxide And Vitamin D Delivery, Reza Mahdavi, Mehran Solati-Hashjin, Meisam Omidi, Arash Khojasteh, Fateme Fayyazbakhsh

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the Most Interesting and Recent Insights into Biomimetic Scaffold Nano-Biomaterial is Smart Scaffolding with Targeted Drug Delivery Ability. in Recent Decades, the Use of Graphene-Based Materials, Such as Nano-Graphene Oxide (NGO), as a Drug Carrier with Amphiphilic Properties, Has Attracted Considerable Attention of Scientists and Researchers in This Field. in Addition, One of the Important Global Problems is Increased Vitamin D Deficiency, Particularly in Pregnant and Postmenopausal Women. Therefore, in This Work, by Considering Hydrophobic Properties of Vitamin D, We Attempted to Examine its Loading and Release Both in the Presence of Surfactant and Surfactant-Free NGO-Aqueous Solution. at …

Improving The Technological Process Of The Fertilizer From Centrifugal Fertilizer Apparatus And Setting The Parameters, B. M. Khudayarov, A. A. Mambetsheripova

Acta of Turin Polytechnic University in Tashkent

The construction of a new pneumoinertial actuating element for fertilizer and their mixtures, as well as results of laboratory tests are presented in this article. Values of basic design and process parameters are determined. Width of fertilizer is being increased to 13m.

Mathematical Model Of The Level Processing Of Organic Wastes On Methanogenesis Mixing Process, Shavkat Imomov, Mansur Sultonov, Akmal Rustamov

Acta of Turin Polytechnic University in Tashkent

The article presents the results of the authors' many experiments on organic waste processing in agriculture. The analysis of the existing biogas plants of advanced countries and comparison of the products obtained during the anaerobic treatment of organic agricultural wastes is presented.

Industrial Conveyors’ Taxonomy And Its Applications, A. Hoshimov, A. Rustamov, J. Rozzokov

Acta of Turin Polytechnic University in Tashkent

In any manufacturing processes includes a material handling equipment that can transport raw material or semi-finished products from the one workstation to another. Material handling equipment are designed based on the type of manufacturing product or the process. Therefore, engineers can easily make decision anaylsis while the selection of the most preferred type of industrial conveyors among others. This paper focuses on the industrial conveyors that classifies all available conveyor types. In this work is defined a review that covers most of the currently available literatures and conveyors types that describes industrial conveyors, types, characteristics and applications. A taxonomy is …

Optimal Control And Design Of Functionality To Improve Efficiency And Lifetime Of Proton Exchange Membrane Fuel Cell, Maftuna Eshkobilova, Uktam Salomov, Maksudbek Baydjanov

Acta of Turin Polytechnic University in Tashkent

This work is devoted to identify operating conditions to maximize the life of power supply, meet the required power output and improve fuel consumption efficiency. We devise a framework for designing fuel cell power supplies for field sensor networks, which have important applications in environmental monitoring, wildlife preservation, in disaster monitoring and in border security. The high efficiency, low emission and zero noise pollution features of fuel cells have made them a promising clean power source. Especially, proton exchange membrane fuel cells are promising alternative to conventional fossil fuel system, because they are clean, quiet and operate high efficiencies. However, …

Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

Centralized communication-based control is one of the main methods that can be implemented to achieve autonomous advanced energy management capabilities in DC microgrids. However, its major limitation is the fact that communication bandwidth and computation resources are limited in practical applications. This can be often improved by avoiding redundant communications and complex computations. In this paper, an autonomous communication-based hybrid state/event driven control scheme is proposed. This control scheme is hierarchical and heuristic, such that on the primary control level, it encompasses state-driven local controllers, and on the secondary control level, an event-driven MG centralized controller (MGCC) is used. This …

Numerical Algorithm For Wing-Structure Design, Jeffrey D. Taylor, Douglas F. Hunsaker, James J. Joo

Mechanical and Aerospace Engineering Student Publications and Presentations

Low-fidelity aerostructural optimization routines have often focused on determining the optimal spanloads for a given wing configuration. Several analytical approaches have been developed that can predict optimal lift distributions on rectangular wings with a specific payload distribution. However, when applied to wings of arbitrary geometry and payload distribution, these approaches fail. Increasing the utility and accuracy of these analytical methods can result in important benefits during later design phases. In this paper, an iterative algorithm is developed that uses numerical integration to predict the distribution of structural weight required to support the bending moments on a wing with arbitrary geometry …

Lumped Parameter Modeling Of Quick Coupling, Sanjar Mirzaliev

Acta of Turin Polytechnic University in Tashkent

Quick coupling is a device for easy engagement and disengagement of fluid power lines. Thanks to their modular design, a large variety of connections conforming to international standards is available. High-quality quick-action coupling made of steel, stainless steel, brass or plastic for practically every application contingency. They are the very best, and easiest way to separate a hydraulic line, and to put it back together. In this article, lumped parameters of quick coupling is obtained by using Solid Works Flow Simulation and mathematical model made in Siemens Amesim hydraulic design tool.