bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar Still for Urban Environments
Authors: Anderson Gregory M. , Porter Arthur C. , Dow Douglas E.
Published: March 2016

The supply of water purified for drinking and residential use is insufficient in many underdeveloped regions. Certain methods enable improved supply to rural villages, such as use of basic solar stills. However, urban environments are not suitable for such basic solar stills for several reasons, including a lack of space readily available for multiple solar stills, inadequate infrastructure, and harsh environment due to both people and environmental conditions. The aim of this project was to develop a solar still system that would be suitable for urban residences, which would purify water to provide a clean and drinkable supply. The two major components of the design were the still and the lens, which work together to purify water by tracking the sun and concentrating the sun rays. The primary goal was to contain a functional solar still in a smaller volume. The rate of evaporation was tested for prototyped modules of the design.
Optimum Design of Tractor Clutch PTO Finger by Using Topology and Shape Optimization
Authors: Dogan O. , Karpat F. , Kaya N. , Yuce C. , Genc M. O. , Yavuz N.
Published: March 2016

Tractors are one of the most important agricultural machinery in the world. They provide agricultural activities in challenging conditions by using various agricultural machineries which are added on them. Therefore, there has been a rising demand for tractor use for agricultural activities. During the power transmission, tractor clutches are exposed to high static and cyclic loading directly. Thus, most of clutch parts fail before completing their design life which is under 106 cycles. Especially, because of the high stress, there are a number of fractures and breakages are observed around the pin area of the finger mechanisms. Due to these reasons, it is necessary to re-design these fingers by using modern optimization techniques and finite element analysis.

This paper presents an approach for analysis and re-designs process of tractor clutch PTO finger. Firstly, the original designs of the PTO fingers are analyzed by using finite element analysis. Static structural analyses are applied on these fingers by using ANSYS static structural module. The boundary conditions are determined according to the data from the axial fatigue test bench. Afterwards, the stress-life based fatigue analyses are performed with respect to Goodman criterion. It is seem that the original design of the PTO finger, failed before the design life. Hence, the PTO finger is completely re-designed by using topology and shape optimization methods. Topology optimization is used to find the optimum material distribution of the PTO fingers. Topology optimization is performed in solidThinking Inspire software. The precise dimensions of the PTO fingers are determined by using shape optimization and response surface methodology. Two different design parameters, which are finger thickness and height, are selected for design of experiment and 15 various cases are analyzed. By using DOE method three different equations are obtained which are maximum stresses, mass, and displacement depending on the selected design parameters. These equations are used in the optimization as objective and constraint equations in MATLAB. The results indicate that the proposed models predict the responses adequately within the limits of the parameters being used. The final dimensions of the fingers are determined after shape optimization. The new designs of the PTO fingers are re-analyzed in terms of static and fatigue analysis. The new design of the PTO finger passed the analysis successfully. As a result of the study, the finger mass is increased 7% but it is quite small. Maximum Equivalent Von-Misses stress reduction of 25.3% is achieved. Fatigue durability of the PTO finger is improved 53.2%. The rigidity is improved up to 27.9% compared to the initial design. The optimal results show that the developed method can be used to design a durable, low manufacturing cost and lightweight clutch parts.
An Experimental Study of the Effect of SiO2 Nanoparticles on the Phase Change Characteristics of KNO3-NaNO3 Mixtures for Thermal Energy Storage
Authors: Gimenez-Gavarrell Pau , Fereres Sonia
Published: March 2016

Combining latent and sensible heat storage within a single material has lead researchers to propose off-eutectic salt mixtures for solar thermal energy storage. A binary salt mixture with an off-eutectic composition presents a melting temperature range as opposed to a melting point, providing additional storage capacity through the sensible heat present during the melting/solidification. However, some drawbacks of off-eutectic mixtures include a higher propensity towards incongruous melting, phase segregation of the mixture upon solidification, and thermal cycling issues. Here the solid-liquid transitions of a series of eutectic and off-eutectic KNO3-NaNO3 mixtures are evaluated to determine if the addition of nanoparticles can limit phase segregation yet still present good thermal properties.

Measurements performed with a Differential Scanning Calorimeter show that the effect of nanoparticles is unimportant compared to the difference between eutectic and off-eutectic phase change behavior. Onset temperatures, latent heats, and the width of the phase transition temperature trace during melting/solidification are compared for the eutectic and off-eutectic salt mixtures with and without silica nanoparticles. A reduction in the latent heat is observed and explained through classical mixing theory. The modification of the phase change properties of eutectic and off-eutectic nanofluids are discussed.
Does Subarachnoid Space Protect the Brain From Blast Waves and/or Blunt Impacts?
Authors: Hashemi Siavash , Sadegh Ali M.
Published: March 2016

The objectives of this study is to investigate the transduction of blast wave through the SAS region and the influence of SAS including different types of trabeculae in reducing the strain in the brain, when the head is subjected to a blast wave, and finally, comparing that to a none blast load such as blunt impacts or angular accelerations of the head during contact sports or accidents. This is accomplished through a series of Global/Local models of the head, neck and the brain. Specifically, a validated FE 3D model of the head and neck is subjected to a blast wave and the time dependent local compressive pressure gradient on the dura matter is calculated. Then through several detailed local FE models of the head, consisting Dura mater, Gray matter, Subarachnoid space having trabeculae and the CSF, the strains in the brain are calculated. In the local models different architecture and morphology of the trabeculae (rod shaped and the tree-shaped) are considered. The Global/Local models were analyzed using ABAQUS 6.12. In addition, the same procedure has been carried out for a velocity impact profile corresponding to 1.1 mph. The results revealed that the shape of the trabeculae would not affect the severity of loads transferring to the brain from shock waves in blast scenarios. Moreover, the interaction between the CSF and Tree-shaped trabeculae and rods with smaller cross sections, protect the brain better in impacts.
Pool Boiling Heat Transfer Enhancement of Water Using Brazed Copper Microporous Coatings
Authors: Jun Seongchul , Wi Hyoseong , Gurung Ajay , Amaya Miguel , You Seung M.
Published: March 2016

A novel, high-temperature, thermally-conductive, microporous coating (HTCMC) is developed by brazing copper particles onto a copper surface. This coating is more durable than many previous microporous coatings and also effectively creates reentrant cavities by optimizing brazing conditions. A parametric study of coating thicknesses of 49–283 μm with an average particle size of ∼25 μm was conducted using the HTCMC coating to understand nucleate boiling heat transfer (NBHT) enhancement on porous surfaces. It was found that there are three porous coating regimes according to their thicknesses. The first regime is “microporous” in which both NBHT and critical heat flux (CHF) enhancements gradually grow as the coating thickness increases. The second regime is “microporous-to-porous transition” where NBHT is further enhanced at lower heat fluxes but decreases at higher heat fluxes for increasing thickness. CHF in this regime continues to increase as the coating thickness increases. The last regime is named as “porous”, and both NBHT and CHF decrease as the coating thickness increases further than that of the other two regimes. The maximum nucleate boiling heat transfer coefficient observed was ∼350,000 W/m2K at 96 μm thickness (“microporous” regime) and the maximum CHF observed was ∼2.1 MW/m2 at ∼225 μm thickness (“porous” regime).
An Experimental Characterization of Horizontal Gas-Liquid Slug Flow
Authors: Vicencio Fernando E. C. , Schneider Fábio A. , Cozin Cristiane , Barbuto Fausto A. , Da Silva Marco J. , Morales Rigoberto E. M.
Published: March 2016

The present work is meant to broaden the knowledge on the fluid mechanics of the two-phase slug flows in horizontal pipes by means of an experimental approach. To accomplish this goal, an experimental facility at the LACIT-UTFPR labs consisting of a 25.8 mm ID, 9-m long transparent pipeline was used. A pair of 12×12-node wire-mesh sensors based on electrical capacitance was used to identify the void fraction in each node of the mesh. Bubble velocities, unit cell frequencies, void fractions and the characteristic lengths of this kind of flow were then obtained after a proper signal processing of the experimental data. To verify the measurements, a methodology to evaluate every measurement done in this work was proposed. Due to the intermittent nature of those flows, their characteristic parameters were identified as probability distributions, and approximated by probability density functions (PDF) such as the normal or log-normal ones. Correlations depending upon the inlet superficial velocities of both liquid and gas phases were fitted for the average values and standard deviation of each parameter. Finally, those correlations were compared to the experimental data, with the aim of accurately predicting the aforementioned parameters as functions of the inlet flow variables, so that those parameters can be used in the development of theoretical models for horizontal gas-liquid slug flow.
Robust Design of Horizontal Axis Wind Turbines Using Taguchi Method
Authors: Rao Singiresu S.
Published: March 2016

The robust design of horizontal axis wind turbines, including both parameter and tolerance designs, is presented. A simple way of designing robust horizontal axis wind turbine systems under realistic conditions is outlined with multiple design variables, multiple objectives, and multiple constraints simultaneously by using the traditional Taguchi method and its extensions. The performance of the turbine is predicted using the axial momentum theory and the blade element momentum theory. In the parameter design stage, the energy output of the turbine is maximized using the Taguchi method and an extended penalty-based Taguchi method is proposed to solve constrained parameter design problems. Using an appropriate set of tolerance settings of the parameters, the tolerance design problem is formulated so as to yield an economical design while ensuring a minimal variability in the performance of the wind turbine. The present work provides a simple and economical approach for the robust optimal design of horizontal axis wind turbines.
Determination of Local Convection Heat Transfer Coefficients Inside a Circular Pipe Using Pulsed Laser
Authors: Lin S.-C. , Tambe S. , Lai M.-C. , Jeng S.-M.
Published: March 2016

The determination of local convection heat transfer coefficients of pipe flow using pulsed laser heating (PLH) from a combination of experimental and numerical study is presented in this paper. The method is advantageous because it is fluid-independent, contact-free and high in spatial and temporal resolution. For simplicity, the experiment used water at different temperatures and flow rates inside two long circular tubes which were subject to radiation heating using a finite size (20 mm in diameter) pulsed laser beam. An infrared camera was used to image and measure its surface temperatures. Two correlations for convection heat transfer coefficient in the thermal/combined entry length region were used in this paper for comparison with the experimental results. The experimental results using the thermal circuit method processed by MATLAB® agree well with both correlations. To gain better insight and quantify the uncertainty, a 3-D conjugated heat transfer simulation was carried out using Fluent CFD. The implication of the accuracy and limitation of the PLH method on the determination of local heat transfer coefficients are also discussed in the analysis.
Risk Evaluation and the NFPA 654 Layer Depth Criteria for Dust Explosion and Flash Fire Hazards
Authors: Ramirez Juan C. , Ogle Russell A. , Carpenter Andrew R.
Published: March 2016

What is an acceptable thickness of accumulated combustible dust in an industrial facility?

Combustible dusts present both flash fire and explosion hazards. Companies which generate, handle, process, store, or distribute combustible dusts need to cost-effectively manage these hazards. In the United States, the Occupational Health and Safety Administration (OSHA) has stepped up its enforcement activity and is conducting inspections at these locations to verify that the facility is being operated in accordance with recognized and generally accepted good engineering practices (RAGAGEP). The combustible dust safety standard from the National Fire Protection Association, NFPA 654 (1) is often cited as the RAGAGEP for combustible dust risk management. One aspect of combustible dust risk management is the monitoring and control of fugitive dust accumulation on horizontal surfaces. NFPA 654 gives specific guidance on how to determine an acceptable level of combustible dust accumulation using different risk scenarios. These acceptable levels or thresholds were only recently added as requirements in the 2013 edition of NFPA 654 and there is debate as to whether they are accurate. An examination of this guidance reveals that it is very conservative because it omits consideration of several distinct events necessary for a dust deflagration or flash fire to occur.

NFPA 654, 2013 edition presents four techniques to determine if a flash fire or explosion hazard exists in a building or enclosure. These are: the layer depth criterion, Mass Method A, Mass method B, and Risk Evaluation. The standard gives explicit directions on how to calculate critical layer thickness using the first three methods. The standard does not give guidance on how to conduct a risk evaluation. In this paper we present a risk evaluation based on the NFPA 654 layer depth criteria. We formulate the dust accumulation scenario as a sequence of distinct events, estimate probabilities for each event, and illustrate how the NFPA 654 guidelines generally skew the layer depth criteria towards lower values. It is argued that the NFPA 654 guidance may result in layer depth criteria that are too conservatively low for facilities that manage marginally combustible dusts. In those facilities a more quantitative risk analysis will likely yield better, i.e., more practical criteria.
Safety-Informed Design: Using Cluster Analysis to Elicit Hazardous Emergent Failure Behavior in Complex Systems
Authors: McIntire Matthew G. , Hoyle Christopher , Tumer Irem Y. , Jensen David C.
Published: March 2016

Identifying failure paths and potentially hazardous scenarios resulting from component faults and interactions is a challenge in the early design process. The inherent complexity present in large engineered systems leads to non-obvious emergent behavior, which may result in unforeseen hazards. Current hazard analysis techniques either focus on small slices of failure scenarios (fault trees and event trees), or lists of known hazards in the domain (hazard identification).

Early in the design of a complex system, engineers may represent their system as a functional model. A function failure reasoning tool can then exhaustively simulate qualitative failure scenarios. Some scenarios will be identified as hazardous by hazard rules specified by the engineer, but the goal is to identify scenarios representing unknown hazards.

A clustering method is applied repetitively to the large set of failure propagation results. Then, an algorithm identifies the scenario most likely to be hazardous, and presents it to the engineer. After viewing the scenario and judging its safety, the engineer may have insight to produce additional rules. The collaborative process of computer rating and human judgment will identify previously unknown hazards.

The feasibility of this methodology is being tested on a relatively simple functional model of an electrical power system. Related work applying function failure reasoning to a team of robotic rovers will provide data from a more complex system.
Fundamental Investigation of a Bubble Deformation Process in a Capsule by Pressure Waves for Developing DDS Microcapsules Including Gas Bubbles
Authors: Tamagawa Masaaki
Published: March 2016

This paper describes fundamental investigation for development of SW DDS (shock wave drug delivery systems), especially deformation process of a bubble in a microcapsule composed of membrane, liquid and gas bubble. Specifically, (1) analysis of a bubble deformation process in a capsule by pressure wave, and (2) mathematical analysis of a bubble near the wall, that is a model of a bubble in a capsule are investigated.
Design of a Conceptual Bed Mattress for Reducing Pressure on Bony Prominences
Authors: Salman Ozlem , Bezerra Karolina , Machado José , Carvalho Vitor , Soares Filomena , Leão Celina P.
Published: March 2016

Elderly care emphasizes the social and personal requirements of older people who need assistance with daily activities and health care, where almost always the main caregiver is the other element of the couple (husband or wife). In the context of Wellbeing, and from its perspective, it is important to have information regarding the type of care needed by bedridden elderly people. Regardless of the needs, they desire independence and autonomy in their life so they need better, more efficient and integrated systems for health and social care. Nowadays, there is an increase on the availability of assisted devices that can be used at home, decreasing the constant requirement for health professional assistance. The main objective of this study is to propose a conceptual solution consisting on the development of a bed mattress in order to reduce pressure points and protect fragile elders. Also, it intends to show a solution that may reduce the number of caregivers to only one. Besides it allows a safety design structure, to be able to take care of older people with disabilities in order to live independently and be active in their home.
Analysis of Alternatives for a Multiproduct System Using Geothermal Energy Under Cascade Utilization Concept
Authors: Ambriz Díaz Victor M. , Rubio-Maya Carlos , Belman-Flores Juan M. , Pastor Martínez Edgar , Pacheco Ibarra J. Jesús
Published: March 2016

Geothermal energy is one of the no fossil energy sources that has been utilized mainly for electricity generation, by using the so-called high enthalpy geothermal resource. Nevertheless, low and medium enthalpy geothermal resources are most abundant, but utilized in less extension due mainly to technological barriers or the thermal match between temperature of energy resources and the technology requirements. This work presents the analysis of alternatives for integrating a multiproduct system, producing sequentially electricity, ice and useful heating. For the purpose, the cascade utilization concept is considered for geothermal energy, utilizing low and medium enthalpy resources. To carry out the analysis, it is assumed availability of geothermal hot water with different temperatures typical of already drilled geothermal wells or studied geothermal reservoirs in Mexico. In order to produce electricity, ice and heating for further use (dehydration process or greenhouse heat supply), three cascade levels are proposed to operate sequentially and simultaneously. For electricity generation Organic Rankine Cycles are considered, and for ice production, thermally activated technologies are the best candidates. If necessary, supplementary heat is provided as a mean of geothermal energy upgrade; among the technologies to integrate are parabolic trough collectors, linear Fresnel collectors and biomass boiler. Particularly, with regard to Organic Rankine Cycles, are considered the ones that works with geothermal hot water in the range of 90 °C to 125 °C with rated power output between 25 kWe to 250 kWe. For ice production, two type of machines are under study, i.e. single-effect absorption machines with coefficient of performance around 0.6, and half-effect absorption machines with a value around 0.3 for the coefficient of performance. Absorption machines can be activated thermally with geothermal hot water with temperature in the range of 70 °C to 90 °C. Afterwards, a number of alternatives are proposed to integrate the multiproduct system, which are analyzed and compared both from the energy and economic point of view, obtaining in this way the main energy interactions of the systems, including electricity produced, amount of ice produced and heat availability. In the model, economic indicators are evaluated, obtaining for each alternative the capital cost, simple payback and net present value. Results shows quantitatively that cascade use of geothermal energy is a viable concept to increase the use of low and medium enthalpy geothermal resources with increase of energy performance and improvement of economical profit.
A Wireless-Communication-Based Active Safety System for Articulated Heavy Vehicles
Authors: Mirfakhraie Tina , Liscano Ramiro , Zhu Shenjin , He Yuping
Published: March 2016

This paper presents an active trailer steering (ATS) system using a wireless communication link to facilitate exchanging information among vehicle units of articulated heavy vehicles (AHVs). A challenge for developing and implementing the wireless-communication-based ATS system is to address the problems of delay and packet-loss. Embedding wireless communication transceivers on an AHV may introduce delays for data exchange, and the transmitted data may be lost. Many reasons may lead to the delay and packet-loss, e.g., channel fading, noise burst, interference, etc. The proposed ATS system may prevent unstable motion modes of AHVs if the sensor data reach the controllers/actuators in real-time with an acceptable level of delay and packet-loss. In order to ensure the performance of the ATS control, a Kalman-filter-based estimator is introduced. The estimator uses the available dynamic data to estimate the current states of the AHV in case some sensor information is not available due to a delay or an outage in the wireless communication link. To investigate the effect of the time delay due to the wireless communication on the performance of the ATS control, co-simulations are conducted. The wireless network is modeled using TrueTime toolbox, the ATS controller is designed in SimuLink package, and the AHV model is constructed in TruckSim software. Integrating the wireless network modeled in TrueTime, the ATS controller designed in SimuLink, and the AHV model constructed in TruckSim leads to the co-simulation platform. Under the emulated double lane-change test maneuver, the effects of the wireless communication with two schemes on the direction performance of the AHV are examined.
Design Optimization of a Solar Dish Collector for Its Application With Stirling Engines
Authors: Ferreira Ana C. , Teixeira Senhorinha , Teixeira José C. , Martins Luís B.
Published: March 2016

Solar concentric dish collectors and Stirling engines with cavity receivers are commonly considered for this purpose due to the high efficiency for converting solar radiation into mechanical energy. The study and design of a solar collector of this type, and of its cavity receiver, require solving a mathematical model that take into account the geometric, optical and thermal behavior of all components. With an adequate sizing, not only the useful energy produced on the solar device will meet the energy required for the process, but also the absorber temperature will be the needed for the operation of the Stirling engine. This paper focuses on the construction of a mathematical model that represents the operational performance of a concentric solar dish with cavity receiver for its applications in Stirling engines. The purpose is to develop a designing tool for optimization and for quantifying the effect of changing the values of design parameters over any specific output behavior or the overall performance of the system. The parameters in the optimization include: geometrical variables, i.e., the solar dish diameter, the receiver aperture diameter or the focal length; and optical variables, i.e., rim and incident angles, and irradiation interception factor. The objective is to minimize the solar dish collector cost and calculate the heat available to the Stirling engine, contained in the receiver cavity, to be converted in to mechanical energy. The numerical model was coded in the MatLab® programming language. The results of the simulation disclosed a model able to predict, adequately, the optical and thermal behavior of the described system, so that the model can be used to study the operation and also to design parameters. The optimal results disclosed the configuration of a solar collector dish with a rim angle of about 41° and for a dish diameter of 6.58 m and an aperture receiver of 0.12 m for a minimum cost of 4717 €. It was also concluded that the maximum temperature reached in the absorber of a receiver cavity, is limited mainly by the geometric relationships between the dish diameter, receiver aperture diameter and the aperture ratio, and it is possible to obtain an ideal thermal efficiency of 64%.
Effects of Morphology, Concentration and Contact Duration of Carbon-Based Nanoparticles on Cytotoxicity of L929 Cells
Authors: Srikanth M. , Misak H. , Yang S. Y. , Asmatulu R.
Published: March 2016

Study of nanomaterials and their characteristics have added a new dimension to the rapid development of nanotechnology. Carbon-based nanomaterials are considered to be one of the key elements in nanotechnology since they are known to exhibit a variety of unusual properties which make them beneficial in the field of medicine and bioengineering. Nanoparticles, because of their size are capable of entering the human body by different modes and can spread to different parts by physical translocation or chemical clearance processes and hence requires a thorough understanding of their interaction with biological molecules, sub-cellular units, cells, tissues, and organs. Cytotoxicity of four types of carbon based nanomaterials — Carbon Nanowire (CNW), Carbon Nanotubes (CNTs), Graphene and Fullerene, on L929 mouse fibroblast cancerous cells is evaluated by MTT Assay. An analysis based on morphology, concentration and contact duration is discussed in this paper. Graphene was the most toxic material with an average toxicity of 52.24%, followed by CNTs, Fullerene and CNW. The differences in the toxicity levels has been attributed to different structural arrangements and aspect ratio. Lower concentration levels exhibited lower levels of cytotoxicity in three of the four nanomaterials but contact duration failed to show any fixed trend.
Effect of Cooling Rate on Drop-Tube Processed Commercial Grey Cast Iron
Authors: Oloyede Olamilekan R. , Bigg Tim , Mullis Andrew M.
Published: March 2016

This study focuses on the fundamental of solidification of commercial grey cast iron as a function of the externally applied cooling rate. Grey cast iron powders were prepared using the drop-tube method, which is a good analogue for commercial production via high pressure gas atomization. The as-solidified droplets were collected and sieved into size ranges from > 850 μm to < 53 μm diameter, with estimated cooling rates of 500 K s−1 to 75,000 K s−1, with each sieve fraction being prepared for metallographic characterization. The microstructure and phase composition of the powders were analyzed using XRD, optical and scanning electron microscopy, with the results being compared against a control sample subject to slow cooling in the drop-tube crucible; which has typical grey cast iron microstructure with extensive flake graphite in a largely ferrite matrix. In contrast, flake graphite was absent in virtually all the drop-tube samples, even in those with the most modest cooling rates. Microstructural analysis revealed that as the cooling rate increased there was less fragmentation of the primary austenite/ferrite dendrites and the volume fraction of primary dendritic material increased. Hence, as the particle fractions get smaller (D < 106 μm) there is a distinct microstructural evidence of a martensite phase which is related to its better mechanical properties (microhardness) as the sample sizes decrease.
CFD Simulation of a 6-Cylinder Diesel Engine Intake and Exhaust Manifold
Authors: Wang Di , Zhang WeiWei , Liu Daokun , Chen Xia , Tang Guangwu , Okosun Tyamo , Wu Bin , Zhou Chenn Q.
Published: March 2016

Exhaust gas recirculation (EGR) is a nitrogen oxide (NOx) emissions reduction technique used in petrol/gasoline and diesel engines. By recirculating a portion of an engine’s exhaust, inert gas displaces combustible matter in the cylinder. Because NOx forms primarily when a mixture of nitrogen and oxygen is subjected to high temperature, the lower combustion chamber temperatures caused by EGR decrease the amount of NOx combustion generates. This project aims at optimizing the location of the EGR ports, which are crucial to the operation and efficiency of the EGR system. The Computational Fluid Dynamics (CFD) code ANSYS FLUENT was used to analyze the intake and exhaust manifold working processes. In order to conduct numerical optimization on determining the best EGR port location, a transient CFD model was developed. Real operational transient boundary conditions were applied to the model through user defined functions (UDF), and the results of flow characteristics and EGR distribution was analyzed in detail. The EGR mass flow rate mal-distribution was presented at the transient simulation. This model can be utilized for further optimization purposes.
Retracted: “The Mechanical Performance of Subarachnoid Space Trabeculae” [ASME 2015 International Mechanical Engineering Congress and Exposition, Volume 3: Biomedical and Biotechnology Engineering, Houston, Texas, USA, November 13–19, 2015, Conference Sponsors: ASME, ISBN: 978-0-7918-5738-0, Copyright © 2015 by ASME. Paper No. IMECE2015-52463, pp. V003T03A092; 3 pages; doi:10.1115/IMECE2015-52463]
Authors: ASME
Published: March 2016

The above referenced paper has been removed from publication. July 5, 2016.

Copyright © 2016 by ASME
How Reliable Is the Extrapolation? Localized Particle Deposition Patterns in Human/Rat Nasal Cavities
Authors: Shang Yidan , Dong Jingliang , Inthavong Kiao , Tu Jiyuan
Published: March 2016

To improve the understanding of dose-response extrapolation from rat to human, regional micro-particle deposition patterns are numerically investigated and compared between human and rat realistic nasal cavities using Computational Fluid Dynamics (CFD). Resting breathing conditions are chosen and airflow patterns are visualised by streamlines. To have better comparisons of deposition patterns, deposited particles are projected into pre-divided 2D domains based on anatomical features using surface-mapping technique. The results show significant differences between human and rat due to the different nasal geometries, especially at vestibule regions. In human case, large micro-particles deposit primarily in vestibule, septum and pharynx and small micro-particles relatively scattered in the whole cavity. On the contrary, in the rat case, large and small micro-particles are captured by the first and second bend of vestibule region.
Fully Coupled Multiphysics Simulation of Enhanced Thermal Conductivity UO2-BeO Fuel Behavior
Authors: Liu Rong , Zhou Wenzhong
Published: March 2016

Commercial light water reactor fuel UO2 has a low thermal conductivity that leads to the development of a large temperature gradient across the fuel pellet, limiting the reactor operational performance due to the effects that include thermal stresses causing pellet cladding interaction and the release of fission product gases. This study presents the development of a modeling and simulation for enhanced thermal conductivity UO2-BeO fuel behavior in a light water reactor, using self-defined multiple physics models fully coupled based on the framework of COMSOL Multiphysics. Almost all the related physical models are considered, including heat generation and conduction, species diffusion, thermomechanics (thermal expansion, elastic strain, densification, and fission product swelling strain), grain growth, fission gas production and release, gap heat transfer, mechanical contact, gap/plenum pressure with plenum volume, cladding thermal and irradiation creep and oxidation. All the phenomenal models and materials properties are implemented into COMSOL Multiphysics finite-element platform with a 2D axisymmetric geometry of a fuel pellet and cladding. UO2-BeO high thermal conductivity nuclear fuel would decrease fuel temperatures and facilitate a reduction in pellet cladding interaction from our simulation results through lessening thermal stresses that result in fuel cracking, relocation, and swelling, so that the safety of the reactor would be improved.
A New Technique for Evaluating Disassembly and Maintenance Using an Example of Underground Escalator
Authors: Shetty Devdas , Poudel Naresh , Xu Jiajun
Published: March 2016

Few products are designed for disassembly or easy dismantling. As manufacturers recognize their responsibility for products at the end of their operational lives, the dismantling of products has emerged as a serious consideration in manufacturing. Disassembly is generally achieved by taking apart individual components or subassemblies of a large product. In situations involving integrated design principles, certain assembly procedures or joining techniques can make the disassembly of a product and separation of components into useful and non-useful groups very difficult. Designers are becoming steadily aware of the problem, and are employing techniques that allow them to design with greater responsibility - Design for Disassembly (DFD) is such techniques. In the case of a durable good with a long life cycle or a product with parts subject to wear, maintainability/serviceability may be more important than initial product acquisition cost, and the product must be designed for easy maintenance. The DFD principles identify the ease with which products can be fabricated, maintained, serviced, and recycled.

This paper examines a special case of evaluation of escalator housing using DFD method. Escalator system plays an important role in transporting passengers safely between underground and station platforms. However, due to the complex working conditions such as uneven load, extreme weather etc. of the escalator system, maintenance is constantly needed and unexpected failure and repair also happens frequently. The escalators used in train subway/metro stations are exposed to some extreme operating conditions such as extreme weather/temperature, uneven loads and shock etc. that can greatly shorten their life span. The increase to labor and maintenance cost impedes the escalator’s ability to efficiently serve its riders and affects its overall stability. The failure and repair of the escalator systems take a significant amount of labor and cost, in addition to customer dissatisfactions. This paper examines and identifies different types of failure modes and defects that occur in the major components of escalator drive systems, such as the motor and its drive chain system, handrail and its drive system, bearings/lubrication systems that are in adjunct with the bearing shaft assembly. The normal maintenance and repair of these sub systems is time consuming. For evaluating the design of the in the escalator, a new approach involving Rating Chart is used. This paper examines various existing DFD techniques and compares them with the Rating Chart method to evaluate DFD efficiency. The paper concludes by showing the robustness of the new DFD methodology in an environment where the products are exposed to extreme working conditions.
Concentration Characterization of Encapsulated Macromolecules in Electrospun Alginate Fibers Using Image Analysis
Authors: Yan Karen Chang , Rossini Michael , Sebok Michael , Sperduto John
Published: March 2016

Electrospun fibers made of biocompatible polymers have been used as scaffolds in tissue engineering to mimic the fibrous environment found in the extracellular matrix (ECM) of biological tissue; and bioactive macromolecules can also be encapsulated in the electrospun fibers. In order to control the release of these encapsulated macromolecules, it is of great interest to understand how the release rate is affected by the sizes of molecules, cross-linking as well as electrospinning configuration (single axial versus co-axial). Fluorescein imaging technique has been applied in quantifying molecular transport phenomena. This paper presents an image analysis method to establish a baseline correlation between the fluorescent intensity and the macromolecule concentration in the electrospun fibers. In this study, alginate and Poly(ethylene oxide) (PEO) blend polymer aqueous solution (1:1 ratio, 3% w/v) was used to electrospin fibers and fluorescein-isothiocyanate dextran (FITC-dextran) with different molecular weights was chosen as the encapsulated macromolecule. Linear correlation was established based on the statistical analysis of electrospun fiber images, and imaging parameters effects were also identified.
Fracture Mode Analysis of Lithium-Ion Battery Under Mechanical Loading
Authors: Luo Hailing , Jiang Xuqian , Xia Yong , Zhou Qing
Published: March 2016

Due to its extensive application, the safety issue of lithium-ion battery has received increasing attention. For crashworthiness design of battery in electric vehicles, it is of great importance to investigate the response of the battery under mechanical loading and understand the mechanism of internal short circuit.

Quasi-static and intermediate strain rate uniaxial tension tests were conducted on the electrodes and the separators. The high speed camera and DIC (digital image correlation) method were adopted to measure the strain while a self-design load cell was used to measure force in dynamic test. Either loading velocity or loading direction was varied in different tests. The upper limit of the test strain rate achieved 66 /sec. All the component materials showed strain rate dependency and separators demonstrated noticeable anisotropy.

Quasi-static penetration tests were conducted on two different types of pouch cell using steel and plastic punch heads. For both Type A pouch cell and Type B pouch cell, during penetration process using plastic punch head, no significant voltage drop or temperature rise was observed. During penetration process using steel punch head, only Type A pouch cell produced short circuit. When the punch head was removed, the voltage of the cells could recover to certain level. From post mortem examination, it was found that for a single pouch cell, all the electrodes presented the same fracture mode that the stacked anode and cathode formed several fragments in the penetration path, while the separators in between only formed a central crack when the punch head went through. Since the separators had a larger elongation ratio than the electrodes, the extended separators around the rupture location could block the direct and constant contact between anode and cathode, electrodes and steel punch, which explained why no massive internal short circuit was initiated.

The drop tower was used to conduct dynamic penetration test. The results indicated that under dynamic loading, internal short circuit was more likely to be triggered which can be explained by the strain rate effect of the separators.

This study highlighted the importance of the separator to the safety performance of pouch cells.
Study of the Effect of Electrode Microstructures on Battery Performance
Authors: Park Jonghyun , Lee Sangmin , Hoffmann John , Sastry Ann Marie
Published: March 2016

Battery performance reflects the transport and kinetics of related species within the microstructures of battery’s electrode. However, the current homogenized battery models lack detailed morphology of the internal structures of electrodes. In this work, a multiscale battery simulation tool is developed. This model is capable of capturing the impact of microstructures of electrodes on battery performance, by adapting the variational multiscale principle. The developed model is verified through the direct numerical solutions, and compared with the conventional pseudo-2D (P2D) model method. The model has revealed more dynamic battery behaviors related to the variation of the microstructure, such as particle shape, tortuosity, and material composition, while the corresponding result from P2D shows a monotonous change within different structures.
Parameter Estimation for Model Validation of an Energy Storage System During Operation in a Series Hybrid Electric Vehicle
Authors: Khalifi Hasnaa , Compere Marc , Currier Patrick
Published: March 2016

Battery models can be developed from first principles or from empirical methods. Simulink Parameter Estimation toolbox was used to identify the battery parameters and validate the battery model with test data. Experimental data was obtained by discharging the battery of a modified 2013 Chevrolet Malibu hybrid electric vehicle. The resulting battery model provided accurate simulation results over the validation data. For the constant current discharge, the mean squared error between measured and simulated data was 0.26 volts for the 298V terminal voltage, and 6.07E−4 (%) for state of charge. For the extended variable current discharge, the mean squared error between measured and simulated data was 0.21 volts for terminal voltage and 9.25E−4 (%) for state of charge.
Genesis of the Airload Variations on Cylinders of Small Aspect Ratios
Authors: Shukla Dhwanil , Hiremath Nandeesh , Motahari Nicholas , Komerath Narayanan
Published: March 2016

A cylinder of aspect ratio 1 experiences a rich mixture of phenomena when yawed through 360 degrees. Understanding this variation is crucial to aerodynamic load definition for objects of practical shape. This paper uses several diagnostics to explain the detailed airload map of cylinders with length to diameter ratios 0.25 to 4 in steady incompressible flow, at Reynolds numbers from 50,000 to 450,000. A sharp linear variation of side force coefficient with yaw is bounded by apparent stall. Drag and pitching moment depend more on the curved surfaces, while side force is dominated by flow over the end plates. Tuft visualization and stereo Particle Image Velocimetry complement 6-DOF loads. Pressure distributions are obtained from velocimetry as well as from computations. The flow over the suction side shows a curved leading edge vortex followed by reattachment and an aft separation. The lift at low yaw is largely due to suction from the zones near the front corner, while at higher yaw it comes from the pressure difference between the two sides. The presence of helical vortices differentiates the lift generation from models based purely on separation.
Anisotropic Thermal Conductivity Enhancement in Magnetically Aligned Polydimethylsiloxane/Nickel Composite
Authors: Su Junwei , Liu Xiao , Charmchi Majid , Sun Hongwei
Published: March 2016

The need for enhancing the thermal conductivity of Polydimethylsiloxane (PDMS) is increasing in applications such as microfluidics, flexible electronics, and biomedical devices. In this research, PDMS/Ni composites with embedded Nickel (Ni) particle columns, aligned under a static magnetic field, were studied for thermal conductivity enhancement. The volume fraction of Ni particles ranged from 2 to 20% but the strength of the applied magnetic field was fixed at 0.45 Tesla. The distribution and morphology of the column structures were quantitatively analyzed using optical microscopy (OM), scanning electron microcopy (SEM) and digital image processing. A reusable 3ω measurement technique was applied to measure the effective thermal conductivity of PDMS/Ni composites in the parallel direction to the magnetic field. Under a static magnetic field, Ni particles align parallel to the field forming columns. The results illustrated that the diameter of Ni columns increased with increasing particle volume fraction while the center-to-center spacing between columns did not change substantially under the fixed magnetic strength. The magnetically aligned particle columns significantly enhanced the thermal conductivity of PDMS compared to the randomly distributed particles by about two fold.
Research on the Driving Mechanism With PLZT Multi-Patches Combination for Optical Actuation Response Improvement
Authors: Wang X. J. , Huang J. H. , Tang Y. J.
Published: March 2016

PLZT actuators taken as one type of photo-deformable actuators have been widely applied for micro-driven systems and active vibration control of photostrictive laminated flexible structures. However, the slow response of photodeformation of single patch PLZT actuator greatly affects its application. In this paper, the main factors for the slow response of the PLZT actuator are investigated using experimental method. The increasing temperature during light on state and the residual photovoltage and photodeformation during light off state are considered to be the main factors for the slow response of the PLZT actuator. To improve the driving performance of PLZT ceramic, some effective measures through reducing the effect of increasing temperature and eliminating residual photovoltage and photodeformation are proposed and experimentally validated in this paper. Considering the effective measures proposed in this paper, two novel optical driving mechanisms based on PLZT bimorph and multi-patches combination for driving source are proposed.