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Effect Of Sky Conditions On Light Transmission Through A Suspended Particle Device Switchable Glazing, ARITRA GHOSH, Brian Norton, Aidan Duffy 2017 Dublin Institute of Technology

Effect Of Sky Conditions On Light Transmission Through A Suspended Particle Device Switchable Glazing, Aritra Ghosh, Brian Norton, Aidan Duffy

Articles

A suspended particle device (SPD) switchable glazing changes its state from opaque to transparent in the presence of a power supply. SPD glazing's near normal transmission varies with incident angle and clearness index. Due to a lower diffuse component, higher glazing transmission ensues at higher clearness indices. Transmittance values for different azimuthal incident angle for a SPD glazing for its “transparent” and “opaque” states have been determined. In Dublin, below 0.5 clearness index, isotropic diffuse transmittance was prevailed while transmission of direct insolation was dominant above 0.5 clearness index. For south facing vertical plane SPD glazing transmittance ...


Integrated Design Of Downwind Land-Based Wind Turbines Using Analytic Gradients, Andrew Ning, Derek Petch 2016 Brigham Young University

Integrated Design Of Downwind Land-Based Wind Turbines Using Analytic Gradients, Andrew Ning, Derek Petch

All Faculty Publications

Wind turbines are complex systems where component-level changes can have significant system-level effects. Effective wind turbine optimization generally requires an integrated analysis approach with a large number of design variables. Optimizing across large variable sets is orders of magnitude more efficient with gradient-based methods as compared to gradient-free method, particularly when using exact gradients. We have developed a wind turbine analysis set of over 100 components where 90% of the models provide numerically exact gradients through symbolic differentiation, automatic differentiation, and adjoint methods. This framework is applied to a specific design study focused on downwind land-based wind turbines.

Downwind machines ...


Determination Of Aqueous Surfactant Solution Surface Tensions With A Surface Tensiometer, Remelisa Esteves, Birce Dikici Ph.D, Matthew Lehman, Qayyum Mazumder, Nonso Onukwuba 2016 Embry-Riddle Aeronautical University

Determination Of Aqueous Surfactant Solution Surface Tensions With A Surface Tensiometer, Remelisa Esteves, Birce Dikici Ph.D, Matthew Lehman, Qayyum Mazumder, Nonso Onukwuba

Beyond: Undergraduate Research Journal

Surfactant solutions are applicable to engineering systems for cooling equipment for electronics. Surfactants can be added to water to improve heat transfer. An application of using aqueous surfactant solutions can be through microchannel heat sink. Although it is ideal to redesign these systems to reduce heat, it is a costly method. Surfactant solutions at optimal solution concentration can be able to transfer heat quickly and effectively with minimum expense. The surface tension of surfactant solutions is an important parameter for boiling heat transfer and must be taken into consideration. The purpose of this research is to measure surface tension of ...


Determination Of Surfactant Solution Viscosities With A Rotational Viscometer, Remelisa Esteves, Nonso Onukwuba, Birce Dikici Ph.D 2016 Embry-Riddle Aeronautical University

Determination Of Surfactant Solution Viscosities With A Rotational Viscometer, Remelisa Esteves, Nonso Onukwuba, Birce Dikici Ph.D

Beyond: Undergraduate Research Journal

Aqueous surfactant solutions are used in engineering systems for improving boiling heat transfer. The purpose of this research is to determine the viscosities of surfactant solutions and to investigate the effect of composition on viscosity. The results obtained can possibly be used as reference for further study in the effects of surfactant solution viscosities on nucleate boiling. A rotational viscometer was used to determine the viscosities of three surfactant solutions – SLS, EH-14, and SA-9 – of various compositions at room temperature. It was discovered that the viscosities of SLS, EH-14, and SA-9 had a nearly consistent pattern as their compositions increased ...


Evaluation Of An Incompressible Energy-Vorticity Turbulence Model For Fully Rough Pipe Flow, Doug F. Hunsaker 2016 Utah State University

Evaluation Of An Incompressible Energy-Vorticity Turbulence Model For Fully Rough Pipe Flow, Doug F. Hunsaker

Doug Hunsaker

Traditional methods of closing the Boussinesq-based Reynolds-averaged Navier-Stokes equations are considered, and suggestions for improving two-equation turbulence models are made. The traditional smooth-wall boundary conditions are shown to be incorrect, and the correct boundary conditions are provided along with sample solutions to traditional models. The correct boundary condition at a smooth wall for dissipation-based turbulence models is that which forces both the turbulent kinetic energy and its first derivative to zero. Foundations for an energy-vorticity model suggested by Phillips are presented along with the near-smooth-wall behavior of the model. These results show that at a perfectly smooth wall, the turbulent ...


A One-Dimensional Finite-Difference Solver For Fully-Developed Pipe And Channel Flows, Doug F. Hunsaker 2016 Utah State University

A One-Dimensional Finite-Difference Solver For Fully-Developed Pipe And Channel Flows, Doug F. Hunsaker

Doug Hunsaker

An algorithm is developed to solve the fundamental flow cases of fully-developed turbulent flow in a pipe and in a channel. The algorithm uses second-order finite-difference approximations for nonuniform grid spacing and is developed in such a way as to easily facilitate the implementation of several two-equation, Reynolds-Averaged-Navier-Stokes turbulence models. Results are included for the Wilcox 1998 k-ω model.


From Sensor To Street – Intelligent Vehicle Control Systems, Zachariah A. Coles, Thomas A. Beyerl, Imani Augusma, Valentin Soloiu 2016 Georgia Southern University

From Sensor To Street – Intelligent Vehicle Control Systems, Zachariah A. Coles, Thomas A. Beyerl, Imani Augusma, Valentin Soloiu

Papers & Publications: Interdisciplinary Journal of Undergraduate Research

The future of automotive engineering lies in intelligent vehicles. The combined effects of multiple intelligent sub-systems will provide drivers with essential feedback to increase driving safety and reduce fuel wasted in unnecessary acceleration and inefficient traffic routing. Discrete intelligent sub-systems have been increasingly incorporated into consumer vehicles for decades, and continue to evolve. The revolutionary next step in development is fully integrating intelligent capabilities into a total vehicle control system. This may be accomplished through a multilevel control architecture, starting with sensor fusion.

Fused sensors, such as LiDAR and RADAR, will provide their inputs to a single virtual model from ...


Radio Controlled Aircraft, Michael Johnson, Dakota MacGill, Robert Peake, Ryan Wydler 2016 Virginia Commonwealth University

Radio Controlled Aircraft, Michael Johnson, Dakota Macgill, Robert Peake, Ryan Wydler

Michael Johnson

Building an R/C aircraft isn’t exactly a project intent on breaking ground in the field of aerospace engineering, rather it is an opportunity to apply fluid dynamics in a practical manner to gain experience in aeronautical engineering. An aerospace engineer is one who designs and builds aircraft and spacecraft and are often tasked with deeming an aircraft flight worthy or not. We will attempt to predict the feasibility of our custom plane designs using aircraft engineering techniques found through research and through texts provided by our advisor, Dr. Jayasimha. The goal of this design is to design and ...


Peridynamic Modeling Of Ruptures In Biomembranes, Michael Taylor, Irep Gözen, Samir Patel, Aldo Jesorka, Katia Bertoldi 2016 Santa Clara University

Peridynamic Modeling Of Ruptures In Biomembranes, Michael Taylor, Irep Gözen, Samir Patel, Aldo Jesorka, Katia Bertoldi

Michael Taylor

We simulate the formation of spontaneous ruptures in supported phospholipid double bilayer membranes, using peridynamic modeling. Experiments performed on spreading double bilayers typically show two distinct kinds of ruptures, floral and fractal, which form spontaneously in the distal (upper) bilayer at late stages of double bilayer formation on high energy substrates. It is, however, currently unresolved which factors govern the occurrence of either rupture type. Variations in the distance between the two bilayers, and the occurrence of interconnections (“pinning sites”) are suspected of contributing to the process. Our new simulations indicate that the pinned regions which form, presumably due to ...


Peridynamic Modeling Of Ruptures In Biomembranes, Michael Taylor, Irep Gözen, Samir Patel, Aldo Jesorka, Katia Bertoldi 2016 Santa Clara University

Peridynamic Modeling Of Ruptures In Biomembranes, Michael Taylor, Irep Gözen, Samir Patel, Aldo Jesorka, Katia Bertoldi

Mechanical Engineering

We simulate the formation of spontaneous ruptures in supported phospholipid double bilayer membranes, using peridynamic modeling. Experiments performed on spreading double bilayers typically show two distinct kinds of ruptures, floral and fractal, which form spontaneously in the distal (upper) bilayer at late stages of double bilayer formation on high energy substrates. It is, however, currently unresolved which factors govern the occurrence of either rupture type. Variations in the distance between the two bilayers, and the occurrence of interconnections (“pinning sites”) are suspected of contributing to the process. Our new simulations indicate that the pinned regions which form, presumably due to ...


A Proposed Method Of Test For Spoilage Of Fruits And Vegetables, Kristopher R. Lineberry, Michael Pate, Byron F. Brehm-Stecher 2016 Iowa State University

A Proposed Method Of Test For Spoilage Of Fruits And Vegetables, Kristopher R. Lineberry, Michael Pate, Byron F. Brehm-Stecher

Byron F. Brehm-Stecher

This document is intended to provide all procedures and background needed for testing fruits and vegetables for deter- mination of spoilage progression during storage. This method of testing was developed for research into the effect of household refrigeration storage conditions on the shelf life of fruits and vegetables (Pate and Brehm-Stecher 2005). Instructions start with the procurement of the produce and sample preparation prior to placement within the environ- mental chamber. Data collection procedures used throughout the experiments are specified and a checklist for visually identifying physical attributes of “spoilage” and “freshness” are developed. Procedures for the counting of microorgan- ...


Analysis Of Resistant Starches In Rat Cecal Contents Using Fourier Transform Infrared Photoacoustic Spectroscopy, Timothy James Anderson, Yongfeng Ai, Roger W. Jones, Robert S. Houk, Jay-Lin Jane, Yinsheng Zhao, Diane F. Birt, John F. McClelland 2016 Iowa State University

Analysis Of Resistant Starches In Rat Cecal Contents Using Fourier Transform Infrared Photoacoustic Spectroscopy, Timothy James Anderson, Yongfeng Ai, Roger W. Jones, Robert S. Houk, Jay-Lin Jane, Yinsheng Zhao, Diane F. Birt, John F. Mcclelland

Diane F. Birt

Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) qualitatively and quantitatively measured resistant starch (RS) in rat cecal contents. Fisher 344 rats were fed diets of 55% (w/w, dry basis) starch for 8 weeks. Cecal contents were collected from sacrificed rats. A corn starch control was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. To calibrate the FTIR-PAS analysis, samples from each diet were analyzed using an enzymatic assay. A partial least-squares cross-validation plot generated from the enzymatic assay and FTIR-PAS spectral results for starch ...


Survey Of Selected Additively Manufactured Propellant For Arc-Ignition Of Hybrid Rockets, Stephen A. Whitmore, Stephen L. Merkley, Louis Tonc, Spencer D. Mathias 2016 Utah State University

Survey Of Selected Additively Manufactured Propellant For Arc-Ignition Of Hybrid Rockets, Stephen A. Whitmore, Stephen L. Merkley, Louis Tonc, Spencer D. Mathias

Mechanical and Aerospace Engineering Faculty Publications

Results of a testing campaign to assess multiple commercially available three-dimensional printer materials for effectiveness in an arc-ignition system for hybrid rockets are presented. Previously, a form of additive manufacturing known as fused deposition modeling was used to fabricate high-density acrylonitrile butadiene styrene (ABS) fuel grains so that, when properly layered, they possess unique electrical breakdown properties. When subjected to an inductive charge, an electrical arc flows along the layered material surface and seeds combustion when the arc occurs simultaneously with the introduction of an oxidizing flow. This study investigates commercially available three-dimensional printable materials to search for equivalent or ...


Assessing Latrine Use In Rural India: A Cross-Sectional Study Comparing Reported Use And Passive Latrine Use Monitors, Antara Sinha, Corey L. Nagel, Evan A. Thomas, Wolf P. Schmidt, Belen Torondel, Sophie Boisson, Thomas Clasen 2016 London School of Hygiene and Tropical Medicine

Assessing Latrine Use In Rural India: A Cross-Sectional Study Comparing Reported Use And Passive Latrine Use Monitors, Antara Sinha, Corey L. Nagel, Evan A. Thomas, Wolf P. Schmidt, Belen Torondel, Sophie Boisson, Thomas Clasen

Evan A. Thomas

Although large-scale programs, like India's Total Sanitation Campaign (TSC), have improved latrine coverage in rural settings, evidence suggests that actual use is suboptimal. However, the reliability of methods to assess latrine use is uncertain. We assessed the reliability of reported use, the standard method, by comparing survey-based responses against passive latrine use monitors (PLUMs) through a cross-sectional study among 292 households in 25 villages in rural Odisha, India, which recently received individual household latrines under the TSC. PLUMs were installed for 2 weeks and householders responded to surveys about their latrine use behavior. Reported use was compared with PLUM ...


Book Review, Suzanne B. Watson 2016 University of New Hampshire

Book Review, Suzanne B. Watson

RISK: Health, Safety & Environment

Review of the book: HELENA SZEJNWALD BROWN, ET AL., CORPORATE ENVIRONMENTALISM IN A GLOBAL ECONOMY: SOCIETAL VALUES IN INTERNATIONAL TECHNOLOGY TRANSFER. (Quorum Books 1993) [264 pp.] Acknowledgments, bibliography, figures, index, tables. LC 92- 19851; ISBN: 0-89930-802-3. [$49.95. P.O. Box 5007, Westport CT 06881.]


Damage Analysis Of Spot Replacement Sleepers Interspersed In Ballasted Railway Tracks, Sakdirat Kaewunruen, Kritditorn Chamniprasart 2016 University of Birmingham

Damage Analysis Of Spot Replacement Sleepers Interspersed In Ballasted Railway Tracks, Sakdirat Kaewunruen, Kritditorn Chamniprasart

Sakdirat Kaewunruen

The interspersed pattern sleeper, a spot replacement of old timber sleeper with concrete or composite counterparts, of railway track is often used as a temporary maintenance for secondary railway lines such as yards, balloon loops or siding. However, their negative effect on the railway has not been taken into account. It is observed that performance of interspersed tracks can quickly deteriorate after some years.  On this ground, a nonlinear simulation of interspersed sleeper railway is conducted using the finite element program, STRAND7, so that the structural damage analysis can be conducted. Two moving point loads representing an axle load along ...


Investigation Of Risk-Based Maintenance Strategiesfor Turnout Geometry Restoration, Serdar Dindar, Sakdirat Kaewunruen 2016 University of Birmingham

Investigation Of Risk-Based Maintenance Strategiesfor Turnout Geometry Restoration, Serdar Dindar, Sakdirat Kaewunruen

Sakdirat Kaewunruen


Railway turnouts are a critical railway infrastructure with a unique complex geometry. As a consequence, they induce a diverse nature of risk during railway operation. A large number of accidents, collision and derailment in particular, occur on or near railway turnouts. Not only do the accidents result in operational downtime and financial losses, they may also yield the casualties and, occasionally, the loss of life. As a result of such complexity, the maintenance burden of turnouts is remarkably high. To reduce the cost, casualties and faults, a risk-based maintenance strategy for geometry problems of turnouts has been developed. In addition ...


A Microfabricated Segmented-Involute-Foil Regenerator For Enhancing Reliability And Performance Of Stirling Engines: Phase Ii Final Report For The Radioisotope Power Conversion Technology Nra Contract Nas3-03124, Mounir B. Ibrahim, Daniel Danila, Terrence Simon, Susan Mantell, Liyong Sun, David Gedeon, Songgang Qiu, Gary Wood, Kevin Kelly, Jeffrey McLean 2016 Cleveland State University

A Microfabricated Segmented-Involute-Foil Regenerator For Enhancing Reliability And Performance Of Stirling Engines: Phase Ii Final Report For The Radioisotope Power Conversion Technology Nra Contract Nas3-03124, Mounir B. Ibrahim, Daniel Danila, Terrence Simon, Susan Mantell, Liyong Sun, David Gedeon, Songgang Qiu, Gary Wood, Kevin Kelly, Jeffrey Mclean

Gary Wood

An actual-size microfabricated regenerator comprised of a stack of 42 disks, 19 mm diameter and 0.25 mm thick, with layers of microscopic, segmented, involute-shaped flow channels was fabricated and tested. The geometry resembles layers of uniformly-spaced segmented-parallel-plates, except the plates are curved. Each disk was made from electro-plated nickel using the LiGA process. This regenerator had feature sizes close to those required for an actual Stirling engine but the overall regenerator dimensions were sized for the NASA/Sunpower oscillating-flow regenerator test rig. Testing in the oscillating-flow test rig showed the regenerator performed extremely well, significantly better than currently used ...


A Microfabricated Segmented-Involute-Foil Regenerator For Enhancing Reliability And Performance Of Stirling Engines: Phase Iii Final Report For The Radioisotope Power Conversion Technology Nra Contract Nas3-03124, Mounir B. Ibrahim, David Gedeon, Gary Wood, Jeffrey McLean 2016 Cleveland State University

A Microfabricated Segmented-Involute-Foil Regenerator For Enhancing Reliability And Performance Of Stirling Engines: Phase Iii Final Report For The Radioisotope Power Conversion Technology Nra Contract Nas3-03124, Mounir B. Ibrahim, David Gedeon, Gary Wood, Jeffrey Mclean

Gary Wood

Under Phase III of NASA Research Announcement contract NAS3-03124, a prototype nickel segmented-involute-foil regenerator was microfabricated and tested in a Sunpower Frequency-Test-Bed (FTB) Stirling convertor. The team for this effort consisted of Cleveland State University, Gedeon Associates, Sunpower Inc. and International Mezzo Technologies. Testing in the FTB convertor produced about the same efficiency as testing with the original random-fiber regenerator. But the high thermal conductivity of the prototype nickel regenerator was responsible for a significant performance degradation. An efficiency improvement (by a 1.04 factor, according to computer predictions) could have been achieved if the regenerator was made from a ...


A Microfabricated Involute-Foil Regenerator For Stirling Engines, Roy C. Tew, Mounir B. Ibrahim, Daniel Danila, Terrence W. Simon, Susan Mantell, Liyong Sun, David Gedeon, Kevin Kelly, Jeffrey McLean, Gary Wood, Songgang Qiu 2016 NASA Glenn Research Center

A Microfabricated Involute-Foil Regenerator For Stirling Engines, Roy C. Tew, Mounir B. Ibrahim, Daniel Danila, Terrence W. Simon, Susan Mantell, Liyong Sun, David Gedeon, Kevin Kelly, Jeffrey Mclean, Gary Wood, Songgang Qiu

Gary Wood

A segmented involute-foil regenerator has been designed, microfabricated and tested in an oscillating-flow rig with excellent results. During the Phase I effort, several approximations of parallel-plate regenerator geometry were chosen as potential candidates for a new microfabrication concept. Potential manufacturers and processes were surveyed. The selected concept consisted of stacked segmentedinvolute- foil disks (or annular portions of disks), originally to be microfabricated from stainless-steel via the LiGA (lithography, electroplating, and molding) process and EDM. During Phase II, re-planning of the effort led to test plans based on nickel disks, microfabricated via the LiGA process, only. A stack of nickel segmented-involute-foil ...


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