bluuebunny/crossref_metadata_2025 huggingface dataset:
Cavitating Flow in Engine Piston Ring-Cylinder Liner Conjunction
Authors: Shahmohamadi Hamed , Rahmani Ramin , Rahnejat Homer , King Paul , Garner Colin
Published: April 2014

The main function of piston compression ring is to seal the space between the piston and the liner, acting as slider bearing, subjected to reciprocating motion. The compression ring-cylinder liner conjunction has been extensively studied and it is responsible for a significant part of the total frictional parasitic power losses of an engine. Paradoxically, the required sealing function of the compressions ring can result in increased friction. Therefore, in order to improve engine efficiency, it is important to fundamentally understand and subsequently palliate some of these losses. Another problem in any slider bearing-type contact is lubricant film rupture and cavitation in the conjunctional outlet zone, reducing load carrying capacity and potentially leading to erosion damage.

A cavitation model presented in two-phase flow CFD analysis of the ring-bore contact under isothermal conditions. Liquid flow is modelled as a continuous phase and a dispersed phase, representing cavitation bubbles. Many of the fundamental physical processes assumed to take place in cavitating flows are incorporated into the model.
Comparison of 4 Methods for Scalable Kinetic (Fast) Vitrification of Cells: From Theoretical Considerations to Feasibility and Practicality
Authors: Katkov Igor I. , Bolyukh Vladimir F. , Jones Stephen B. , Katkov Vsevolod
Published: April 2014

Kinetic (very rapid) vitrification (K-VF) is a promising approach for cryopreservation (CP) of cells but existing methods are not scalable due to the Liedenfrost effect (LFE), which substantially impedes the rate of cooling. Here, we compare 4 emerging approaches that discuss scalability and ultra-fast cooling, namely, cryogenic oscillating heat pipes (COHP), microstructured evaporation in thin films, K-VF in nanodroplets and thin film evaporation in microstructured with our methods of hyperfast cooling KrioBlastTM. We show that only KrioBlastTM can ensure hyper-fast rates of cooling by elimination of the LFE. The logistics and other aspects of practicality of 4 methods are also discussed.
Second Law Analysis of Heat Transfer in Taylor Couette Flow for Pseudoplastic Fluid
Authors: Hazbavi A. , Ashrafi N. , Najafi M.
Published: April 2014

The Taylor Couette flow of pseudoplastic fluids is examined while dissipation due to viscous effects through the energy balance. The viscosity of fluid is simultaneously dependent on shear rate and temperature. Exponential dependence of viscosity on temperature is modeled through Nahme law and the shear dependency is modeled according to the Carreau equation. Hydrodynamically, stick boundary conditions are applied and thermally, both constant temperature and constant heat flux on the exterior of cylinders are considered. The governing motion and energy balance equations are coupled adding complexity to the already highly correlated set of differential equations. Introduction of Nahme number has resulted in a nonlinear base flow between the cylinders. As well, the condition of constant heat flux has moved the point of maximum temperature towards the inner cylinder. Taking viscous heating into account, the effects of parameters such as Nahme Number, Deborah Number, material time and pseudoplasticity constant on the heat transfer of the flow are investigated by second law analysis. Moreover, the study shows that the total entropy generation number decreases as the fluid elasticity increases. It, however, increases with increasing Nahme Number.
Period-m Motions in a Periodically Forced van der Pol Oscillator
Authors: Luo Albert C. J. , Lakeh Arash Baghaei
Published: April 2014

Period-m motions in a periodically forced, van der Pol oscillator are investigated through the Fourier series expression, and the stability and bifurcation analysis of such periodic motions are carried out. To verify the approximate solutions of period-m motions, numerical illustrations are given. Period-m motions are separated by quasi-periodic motion or chaos, and the stable period-m motions are in independent periodic motion windows.
Experimental and Theoretical Analysis of Subcooled Water Discharge Through Simulated Steam Generator Tube Cracks
Authors: Revankar Shripad T. , Vadlamani Ram Anand , Riznic Jovica R.
Published: April 2014

The steam generator (SG) tubes represent a major fraction of the reactor primary coolant pressure boundary surface area in both Canadian pressurized heavy water reactor (CANDU) reactors and pressurized water reactor (PWR). There is very limited data on the steam generator tube leak rate measurement. Most studies of subcooled choking flow are related to long tubes with L/D greater than 15. Also, all of those data have a channel length greater than 10 mm, which is not indicative of steam generator tubing. Steam generator tubes have a wall thickness typically less than 3 mm. Experiments were conducted on choking flow for various simulated crack geometries for vessel pressures up to 7 MPa with various subcoolings. Measurements were done on subcooled flashing flow rate through well defined simulated crack geometries with L/D at ∼2 and 5–6. Both homogeneous equilibrium and non-equilibrium mechanistic models were developed to model two-phase choking flow through slits. A comparison of the model results with experimental data shows that the homogeneous equilibrium based models grossly under predict choking flow rates in such geometries, while homogeneous non-equilibrium models greatly increase the accuracy of the predictions.
Overview of Planned ASME/VUPRE Conference Meeting on Vulnerability, Uncertainty and Probability Quantification in Regulatory Engineering, and IMECE2012 and FEOFS2013 RE Sessions
Authors: Honda Hiroshi
Published: April 2014

Regulatory engineering came to be increasingly needed by extensive people of our society to maintain safety, security, and sustainability of the environment, economy, energy, mineral and other resources of our planet among others, as engineering is increasingly globalized to meet the needs and wants of a variety of people and society in the world. The ASME/VUPRE Conference on Vulnerability, Uncertainty and Probability Quantification in Regulatory Engineering was to be held in Washington, D. C. on August 16–18, 2012 or thereafter. The current paper provides an overview of the planned conference presentations and discussion, based on the topics planned, and abstracts submitted among others, as well as those for IMECE2012 Session 5-7-2 Globalization of Regulatory Engineering, and the author’s paper on fatigue and fracture issues of an offshore structure, etc., and role of regulatory engineering, prepared for the 9th International Conference on Fracture and Strength of Solids (FEOFS2013) on June 9–13, 2013 in Jeju, South Korea. Possible impacts of the outcome on the regulatory agencies, regulated communities, scientists and engineers, and general public in the United States, Europe and Japan among other nations and regions are also discussed.
The Design and Finite Element Analyses of the Super-Long Ultrasonic Amplitude Transformer
Authors: Wang Yan , Lin Bin , Cao Xiaoyan , Wang Shaolei
Published: April 2014

Super-long amplitude transformer is an indispensable part of ultrasonic vibration system, often used in high power ultrasound applications. This paper put forward a new method to design and analyze super-long amplitude transformer. Firstly, by using the mechanical four-terminal network method to solve one dimensional longitudinal vibration equation, the frequency and vibration ratio of the ultrasonic transformer are obtained. Thereafter, two types amplitude transformers design scheme can be got by theoretical calculation, i.e. exponential and conical amplitude transformer. Finally, using FEM software ANSYS to analyze the modal, stress distribution and harmonic response of the amplitude transformer. According to the finite element simulation results, each of amplitude transformers has advantages and disadvantages. Compared with theoretical results, it is satisfied with demands of engineering. A new way is carried out for design and optimality of super-long amplitude transformer.
New Insights Into Controlling Sub-Micron Failure Mechanisms in Composites Using Discrete Functionalized Multiwall Carbon Nanotubes
Authors: Bosnyak Clive , Hunter Douglas , Stewart Andrew , Swogger Kurt , Zhou Zhenwen
Published: April 2014

New technology has been developed that enables multiwall carbon nanotubes to be discrete, high aspect ratio and well bonded to the composite matrix of choice. Several composite types are examined using tubes of diameter about 12 nm and length about 700nm. Fully discrete, well-bonded tubes are shown to significantly enhance the matrix resistance to fracture and can be placed between fiber plies of composites. The challenges of maintaining the exfoliated state of discrete multiwall carbon nanotubes during composite part assembly from the liquid prepolymer to the cured part are discussed.
Actuator Array Dynamics Incorporating Actuator Inertia
Authors: Bedillion Mark D.
Published: April 2014

Actuator arrays are planar distributed manipulation systems that use multiple two degree-of-freedom actuators to manipulate objects with three degrees of freedom (x, y, and θ). Prior work has discussed actuator array dynamics while neglecting the inertia of the actuators; this paper extends prior work to the case of non-negligible actuator inertia. The dynamics are presented using a standard friction model incorporating stiction. Simulation results are presented that show object motion under previously derived control laws.
Filtration of Particles by a Fiberglass Bed
Authors: Wallis Graham B.
Published: April 2014

This paper was inspired by interest in assessing the effectiveness with which a bed of fibers, composed of fiberglass released from fractured insulation and deposited on a strainer or grid following a loss-of-coolant-accident (LOCA) in a nuclear plant, would filter and trap particulate matter of various sizes and properties. The limiting structures or random morphology of a fiber bed are analyzed, leading to estimates of the pore sizes of the passages through which the particulate suspension flows, and the likelihood of entrapment is then deduced. This multiphase flow topic appears particularly appropriate for the symposium as it exemplifies Professor Zuber’s characteristic approach of using fundamental mechanics and mathematics to derive approximate and effective models of physical reality.
The Effect of Flow Pulsation on Ultrafiltration System Limiting Flux Behavior
Authors: Huang Chyouhwu Brian , Chen Hung-Shyong
Published: April 2014

Ultrafiltration (UF) is an important industrial operation and is found in the food industry, separation of oil-water emulsions, treatment effluents from the pulp and paper industry, and environmental protection systems. Despite being widely used in these areas, UF systems exhibit a limiting flux behavior caused by concentration polarization on the membrane surface. Concentration polarization can be severe in macromolecular solutions due to low diffusivity on membrane separation and both mechanical and chemical methods have been used to reduce this phenomenon.

This study introduces a new mechanical method that improves the performance of membrane separation and decreases concentration polarization. It involves pulsing the feed flow discontinuously and based on our results, feed flow velocity and solution bypass/membrane filtration time ratio are two vital factors when it comes to improving permeate flux. The proposed method is expected to find wide application, particularly in the processing of macromolecular solution.
Forensic Engineering Analysis Methods Employed for the Purpose of Determining the Location of a Long-Range Shooter Based on Terminal Bullet Trajectory
Authors: Knox Michael A.
Published: April 2014

The reconstruction of shooting incidents based on the terminal bullet trajectory is commonly carried out over short distances using a linear trajectory simplification model. However, when shooting incidents, such as sniper attacks, take place over longer distances, linear simplification models destabilize and result in large errors in determining the location of the shooter. In such cases, it becomes necessary to account for a large number of variables affecting the flight path of the bullet.

While linear simplification models for bullet trajectories do not require robust engineering analysis methods, reverse modeling of long-range bullet trajectories can only be carried out using numerical methods for solving the differential equations of projectile motion.

This paper will explore methods for employing computational engineering methods to model the trajectories of bullets with a focus on reverse modeling from the trajectory terminus. In this way, the forensic engineer can use basic measurements of the terminal angle of the bullet trajectory combined with appropriate knowledge of the firearm and ammunition to model the bullet’s path back to a probable location of the shooter.

This paper will focus on methods that the forensic engineer can employ when solving problems involving determination of the location of a shooter based on limited physical evidence at the scene. Computational analysis tools will be presented.
Coupling of Micro-Scale and Macro-Scale Eulerian-Lagrangian Models for the Computation of Shocked Particle-Laden Flows
Authors: Davis Sean , Sen Oishik , Jacobs Gustaaf , Udaykumar H. S.
Published: April 2014

The accuracy and efficiency of several algorithms that couple output from full resolution micro-scale Direct Numerical Simulation computations to input for macro-scale Eulerian-Lagrangian (EL) methods for the computation of high-speed, particle-laden flow are assessed. A Stochastic Collocation method, a Gaussian Radial Basis Function (RBF) Artificial Neural Network (ANN), and an improved RBF-ANN are compared for the fitting of an analytical drag coefficient formula that depends on Mach number and Reynolds number. The improved RBF-ANN uses a clustering algorithm to enhance conditioning of interpolation matrices. The fitted drag coefficient mantle, used to trace point particles in macro-scale computations, is in excellent agreement with the analytical drag formula. The SC method requires fewer micro-scale realizations to obtain comparable accuracy of the drag coefficient. The Gaussian RBF does not converge monotonically, while the improved RBF-ANN converges algebraically and has the potential to provide error estimates.
Effect Analysis of Dimensional Tolerances on the Dynamic Characteristics of Hydrodynamic Journal Bearing System
Authors: Wei Yuan , Chen Zhaobo , Xu Wubin , Jiao Yinghou
Published: April 2014

According to the exist of dimensional tolerances on hydrodynamic journal bearing system, a nonlinear oil film force model was developed, emphasis on the different dimensional tolerances in the system, the tolerances of dynamic viscosity, bearing width, bearing diameter and journal diameter along with its interaction effect to the dynamics characteristics of the hydrodynamic journal bearing system were analyzed. By using the eccentricity corresponding to the stability threshold velocity, the effects of the stiffness and damping coefficients, carrying capacity, system stability and friction power loss brought by the dimensional tolerances of the dynamic viscosity, bearing width, bearing diameter and journal diameter was quantitative analyzed. The results show that in contrast to the impacts of the tolerances in bearing diameter, dynamic viscosity and bearing width, the journal diameter tolerance would lead to a negative effect, and the dimensional tolerances have different degrees of impacts on the journal bearing system. The energy decreased as the eccentricity increased, when the eccentricity is 0.6948 the friction energy reach to a minimum. It provides a theoretical basis to select reasonable parameter, find the best solution and control varieties of nonlinear dynamical behavior.
Hemorheology and the Flow Behavior in a Separated Flow Region
Authors: Hammad Khaled J.
Published: April 2014

Separating flows can be encountered in the cardiovascular circulatory system and many biomedical applications such as artificial organs, rotary blood pumps, heart valves, stents, catheters, and probes. The current study investigates the influence of hemorheology on the flow behavior in a confined separated flow region. Recent hemorheological models and data are utilized to account for the yield stress and shear-thinning non-Newtonian characteristics of human blood. The flow field information is obtained by numerically solving the governing mass and momentum conservation equations along with the Herschel-Bulkley rheological model. The yield shear-thinning model always results in the smallest flow separation region. The yield stress and shear-thinning non-Newtonian models predict lower recirculation strength in comparison with the Newtonian model.
Boundary Layer Separation Control on an Inclined Plate Using Jet and Vortex Actuator
Authors: Cadirci Sertac , Gunes Hasan
Published: April 2014

In this numerical study a Jet and Vortex Actuator (JaVA) system is implemented on an inclined plate (with an inclination angle 6°) to control the laminar boundary layer separation. JaVA is an active flow control device similar to the synthetic jets that transports momentum into the boundary layer and interacts with the boundary layer velocity profiles.

The JaVA used in this study is a two-dimensional rectangular cavity with an actuating plate mounted on the opening which is placed asymmetrically. The plate moves up and down in vertical direction with a specified frequency. As the actuating plate is mounted asymmetrically on the cavity-opening, there are one narrow (wn) and one wide gap (ww) between the plate and the cavity.

First JaVA in a cross-flow on an inclined plate (with inclination angle 6°) is modeled using a computational domain including a moving zone to mimic the vertical motion of the actuating plate. As plate moves up and down like a piston, JaVA-induced vortices emanate from the wide gap and are injected into the oncoming boundary layer.

The calculations are carried out by a commercial finite-volume-based unsteady, laminar, incompressible Navier-Stokes solver. Time-averaged flow fields are calculated to extract boundary layer profiles from various downstream stations. For different oscillation frequencies (f = 1, 2, 3 and 4 Hz) time averaged boundary layers are compared to the non-actuated case (f = 0). The variations of the important boundary layer characteristics (displacement thickness, momentum thickness, shape factor) as well as friction coefficient are also investigated. It is observed that with increasing plate frequency or jet-Reynolds number (ReJ = 4abf/ν), JaVA-induced vortices interact with the cross-flow and modify the boundary layer characteristics. This has been shown in the time-averaged velocity profiles with a fuller shape causing larger displacement thicknesses and in association with them the shape factors drop and the friction coefficients increase.

The proposed control method based on alternating suction and blowing with an oscillating plate is effective in delaying or preventing the flow separation downstream of an inclined plate.
Effect of Sagittal Sawing Parameters on Histopathology of Bone
Authors: Chang Gerard , Micucci Steven , Smith Eric , Cassidy Charles , Quinto Tobi , Sagar Amrit , James Thomas P.
Published: April 2014

A sagittal saw is used for resection of bone during joint replacement surgery. During sawing, tissue at the cut surface can be damaged by high temperatures, which may lead to aseptic loosening of implants. To date, there have been no studies relating sagittal sawing parameters to the level of tissue necrosis. The aim of this study was to determine the feasibility of using histopathological analysis in assessing the severity of thermal necrosis due to sawing. All sawing experiments were performed on cortical bone taken from fresh bovine femur. A two factor, two level design of experiments was performed looking at applied thrust force from 15 N to 30 N and blade oscillation speed from 12,000 cpm to 18,000 cpm. Each cut was subjected to standard histological preparation and the depth of empty lacunae was measured. Both experimental factors, force and speed, showed a statistically significant effect on the depth of thermal necrosis (p< 0.05). However, the interaction of speed and force did not prove to be statistically significant (p = 0.22). From a clinical perspective, the results indicate that choosing higher blade speeds and applying greater force can reduce the amount of thermal damage during sagittal sawing.
Stochastic and Deterministic Vibration Analysis on Drill-String With Finite Element Method
Authors: Qiu Hongyuan , Yang Jianming
Published: April 2014

Using Euler-Bernoulli beam theory, a finite element model with six degrees of freedom per node is developed for a drill-string assembly. The drill-string is driven by a DC motor on the top and is subjected to distributed loads due to its own weight as well as bit/formation interaction. The model is axial-torsional, lateral-torsional coupled. Under deterministic excitations, the model captures stick-slip behavior in drilling operation. Analysis on its negative effect on drilling performance are made, and potential mitigation measures are also discussed. In random model, the excitations to the drill-bit are modeled as combination of deterministic and random components. Monte Carlo (MC) simulation is employed to obtain the statistics of the response. Two cases of random excitation with different intensities are investigated. The results from MC simulation are compared against that from deterministic case.
A Simple Method for Measuring Muffler Transmission Loss With PU Probes
Authors: Yan Li , Jiang Weikang
Published: April 2014

The conventional approaches for measuring muffler transmission loss based on measurement in impedance tube are mainly decomposition methods and transfer matrix method. The decomposition method needs an anechoic termination, but it is not easy in some cases particularly for low frequency measurement. Two-load method and two-source method based on transfer matrix techniques are considered to be an alternative approach which does not require an anechoic termination. PU probe can measure both sound pressure and particle velocity, which is applied to some acoustic measurement such as absorption coefficient in recent years. A straightforward method for measuring muffler transmission loss by two PU probes measuring particle velocity at the inlet and outlet of muffler is presented. The four-pole parameters of the muffler can be calculated directly. The transmission loss measured by the PU method agrees well with the result measured by conventional four-pole method and FEM result. To instruct the approach, the influence of measurement distance between PU probe and the inlet or outlet of muffler and ambient noise are analyzed, which gives comprehensive suggestions for measurement set up.
Micro FEM Simulations of Single-Cutting-Edge Sawing of Cortical Bone
Authors: Hage Ilige S. , Hamade Ramsey F.
Published: April 2014

The finite element method at the micro scale (mFEM) has been gaining in popularity to simulate biomechanical effects. In this paper, a 3D mFEM model is developed to simulate sawing of cortical bone under 2D orthogonal cutting conditions. The aim of the research was to develop a predictive model of the sawing forces and to report them as a function of depth of cut. To obtain the micro geometric input, a heterogeneous anisotropic model was created from several images taken via an optical microscope of the cortex of adult mid-diaphysal bovine femur. In order to identify the various regions representing the micro-architecture of cortical bone, such as osteons, Haversian canals, lamellae and lacunae, MATLAB was utilized for intelligent image processing based on pulsed coupled neural networks. After each micro-phase in the image was assigned the proper mechanical properties, these material-tagged micro-features were imported into the finite element method (FEM) solver. Results from the simulation were correlated to cutting force data that was determined experimentally. Experiments were conducted with individual stainless steel saw blade teeth that were removed from a typical surgical saw blade. The teeth were 0.64 mm thick, with a rake and clearance angle of −10 and 60 degrees, respectively. Representative of clinical conditions for power bone sawing, depths of cut per tooth between 2.5 micrometer and 10 micrometer were investigated. The simulated cutting forces from the mFEM model compared favorably to the experimental data.
Feasibility Study of a Supercritical Cycle as a Waste Heat Recovery System
Authors: Agresta Antonio , Ingenito Antonella , Andriani Roberto , Gamma Fausto
Published: April 2014

Following the increasing interest of aero-naval industry to design and build systems that might provide fuel and energy savings, this study wants to point out the possibility to produce an increase in the power output from the prime mover propulsion systems of aircrafts. The complexity of using steam heat recovery systems, as well as the lower expected cycle efficiencies, temperature limitations, toxicity, material compatibilities, and/or costs of organic fluids in Rankine cycle power systems, precludes their consideration as a solution to power improvement for this application in turboprop engines. The power improvement system must also comply with the space constraints inherent with onboard power plants, as well as the interest to be economical with respect to the cost of the power recovery system compared to the fuel that can be saved per flight exercise. A waste heat recovery application of the CO2 supercritical cycle will culminate in the sizing of the major components.
Heating of Long-Stroke Magnetorheological Fluid Damper
Authors: Zheng Jiajia , Li Zhaochun , Wang Jiong
Published: April 2014

Magnetorhelogical (MR) dampers are gradually used in military devices for shock isolation and civil structures for suppressing earthquake-induced shaking and wind-induced vibrations because of their mechanical simplicity, high dynamic range, low power requirements, large force capacity and robustness. Since MR fluid dampers are energy-dissipating device, the issues of heat generation and dissipation is important. In this study, phenomenon of viscous heating and consequent temperature increase in a long-stroke MR damper are presented. In addition, a theoretical model is developed which predicts the temperature increase in the long-stroke MR damper. This model is solved numerically and a new coupling method was proposed to analyze the electromagnetic-thermal coupling problem on the basis of the mechanism of coupled field. Aim at the high frequency of piston head moving back and forth, as well as the changing current, the simulation model is established. The results show that the temperature effect on the damping force is significant and provide a theoretical basis and calculation method for the design and analysis of long-stroke MR damper.
The Effect of Gas Models on Compressor Efficiency Including Uncertainty
Authors: Lou Fangyuan , Fabian John , Key Nicole L.
Published: April 2014

Since isentropic efficiency is widely used in evaluating the performance of compressors, it is essential to accurately calculate this parameter from experimental measurements. Quantifying realistic bounds of uncertainty in experimental measurements are necessary to make meaningful comparisons to CFD simulations. This paper explores how the gas model utilized for air can impact not only the efficiency calculated in an experiment but also the uncertainty associated with that calculation. In this paper, three different gas models are utilized: the perfect gas model, the ideal gas model, and the real gas model. A commonly employed assumption in calculating compressor efficiency is the perfect gas assumption, in which the specific heat, is treated as a constant and is independent of temperature and pressure. Results show significant differences in both calculated efficiency and the resulting uncertainty in efficiency between the perfect gas model and the real gas model. The calculated compressor efficiency from the perfect gas model is overestimated, while the resulting uncertainties from the perfect gas model are underestimated. The ideal gas model agrees well with the real gas model, however. Including the effect of uncertainty in gas properties results in very large uncertainties in isentropic efficiency, on the order of 10 points, for low pressure ratio machines.
Federative Data Management Based on Unified XML Data Scheme to Support Prosthetic Dentistry Workflows
Authors: Heister Reinhard , Anderl Reiner
Published: April 2014

The laboratory side of a digital dental workflow consists of heterogeneous software tools including digitization (scanning), modeling (CAD), production planning (CAM) and production. The heterogeneity can be structured in two dimensions: ‘various partial systems’, composing the dental product development system and ‘various vendors’, offering software solutions for these partial systems. As a result the value creation process lacks efficiency and different input/output data streams are still necessary. As a standard for the representation of geometric data the STL format has been established, whereas for additional information, such as organizational and administrative data, as well as requirements and design data, the XML (eXtensible Markup Language) format is considered appropriate. However, a variety of proprietary XML data formats have been developed by system vendors. Thus incompatibilities are a significant source for errors. Data flow structures as available today only allow unidirectional flow of information ‘downstream’.

A new approach is based on a federative workflow data management. The basic concept is a unified XML scheme that represents data about all activities and states of dental objects created throughout the whole cycle of dental process. The new unified XML scheme provides a data structure, which can be adapted for the respective input/output data streams of all partial systems. The XML scheme represents a unified data scheme which allows both vertical (within a certain partial system class) and horizontal (along the digital dental workflow and independent of system vendor) data usage. Each dental system supplier only needs to create one input and output filter for the neutral XML interface. The system architecture is based on a web server to which a XML database server is connected. The XML database server manages project specific XML databases. Data can be made available through REST-, as well as through WebDAV-interface on LAN or WAN. With the help of XPath and XQuery required data can be extracted from the database. Redundant data input as well as incompatibility errors can be avoided by this approach.

The innovative core is a unified workflow data format, in which a bidirectional data flow can be provided for both downstream and upstream, along the digital dental workflow.
The Effect of Mixed Hydrophilic and Hydrophobic Surfaces on Frost Nucleation and Growth
Authors: Van Dyke Alexander S. , Betz Amy Rachel
Published: April 2014

The purpose of this research is to test hydrophilic, hydrophobic, and mixed hydrophobic and hydrophilic (biphilic) surfaces to see how theses surfaces affect frost nucleation and growth. Frost forms when humid air comes into contact with a surface that is below the dew point and freezing temperature of water. Many engineering systems are hindered by frost, such as aeronautics, refrigeration, and electrical transmission wires. Most recent research on frost formation has looked at making superhydrophobic materials, which lower the freezing point and increase the frost formation time. These materials are very dependent on operating conditions and surface roughness, which fluctuate often. A hydrophobic surface delays frost growth more than a hydrophilic surface and also creates a taller, less dense frost layer than the hydrophilic surface. Our hypothesis is that a biphilic surface will be better at slowing the frost formation process as well as creating a less dense frost layer. The water in the air will preferentially condense on the hydrophilic areas, thus controlling where the nucleation will first occur. This could help to control the size, shape, and location of the frost nucleation.
Application of Advanced Problem Solving Software in Conceptual Design
Authors: Bzymek Zbigniew M. , Xu Yang
Published: April 2014

This paper is devoted to the application and evaluation of the software supporting the problem solving in engineering conceptual design. This is a companion paper with IMECE 2012 [1]. Though the situation is slightly better now than in previous years, there is still no software suitable for a completely satisfactory automation of the engineering conceptual design process. However there are some program packages that could be the most helpful and would greatly influence the quality of the designed product, especially in cases of contradicting constraints. In this paper some results of research on the use and effectiveness of Invention Machine (IM™) software products are presented. As reported before such packages as Invention Machine V.2 for Windows, TechOptimizer V. 3.5, and TechOptimizer V.4 were used extensively giving excellent results in teaching, research and practical applications. In this paper some experience in use of Goldfire V. 6.5, Goldfire V.7 and Goldfire V.7.5, that was recently introduced is reported and evaluated. The content and effectiveness of the programs in teaching are discussed. Examples of applications are given, conclusions are derived, and the recommendations for the future use of the software are offered.
PIV Analysis of the Flow Pattern Around an Ablation Catheter to Observe the Flow Effect on the Electrode
Authors: Yu Kaihong , Yamashita Tetsui , Shingyochi Shigeaki , Matsumoto Kazuo , Ohta Makoto
Published: April 2014

Radiofrequency (RF) catheter ablation is a highly effective treatment for many cardiac arrhythmias, especially for tachyarrhythmia. RF energy is introduced through the catheter onto the endocardial surface to destroy the abnormal heart tissue causing the heart rhythm disorder. Many parameters relate to myocardial temperature, such as RF power, tissue contact, and blood flow. Blood flow is an important factor that has a cooling effect on myocardium and affects the final lesion size. Many previous studies have shown that under temperature control, lesion sizes are larger and tissue temperatures rise faster with a high flow rate. If the flow causes a decrease in the temperature of the catheter tip, the generator will increase the power output to maintain the tip at a constant temperature. However, few studies of RF catheter ablation have investigated how ablation affects blood flow. Observation of the flow pattern around the catheter can help to determine the mechanism of the flow effects on the temperature of the catheter tip. The purpose of this study is to observe the flow pattern during ablation using an in-vitro circulation system developed for Particle Image Velocimetry (PIV). We developed an open-channel circulation system to simulate blood flow. The mold for the open-channel was built with acrylic boards for transparency. The working fluid was 0.9% saline, which was used at room temperature (20°C). Instead of animal myocardium, we used a poly (vinyl alcohol) hydrogel (PVA-H), which has mechanical characteristics that approximate those of biological soft tissue, and contact with the PVA-H surface by the catheter is similar to that with myocardium. A 7 Fr catheter with a 4-mm ablation electrode tip was set perpendicular to the PVA-H surface, and the contact weight between the electrode of the catheter and the PVA-H surface was 2.2 gf. To measure the temperature profile in the PVA-H, a K-type thermocouple with the diameter of 0.5 mm was placed at the depth of 2 mm from the surface. The thermocouple tip was always placed on the catheter axis. The flow pattern at the location where the catheter was held was observed by a high speed camera, and the resulting images were analyzed by particle image velocimetry (PIV). The results showed that in the absence of applied flow, convection flow from the electrode is observed in the areas around the catheter. However, under a 1.6 L/min flow rate, convection flow disappears. In conclusion, blood flow could decrease the catheter tip temperature, and the influence of ablation in the flow around the catheter disappeared.
Heat Recovery From Bottom Ash in Waste Fired Boilers: Status of Technologies and Thermal Performance Modeling
Authors: Zakariya Kaneesamkandi M.
Published: April 2014

Bottom ash from Municipal Waste fired boilers have sufficient heat content and this can be used to pre-heat the boiler feed water or the combustion air. A study of the recent developments in this area is done with a focus on the air based cooling method. Modeling and simulation of the thermal performance of an air cooled ash cooling system is done with the help of Gambit/Fluent software. Among several methods of waste disposal, incineration of Municipal Waste is opted mainly due to its energy potential and specific advantages like high volume reduction ratio and convenience in plant location. However, the inherent fuel qualities that confront this method are its high moisture and ash content and the consequent low calorific values. The fuel bed temperature in stoker fired incineration systems can reach up to 1200K and a considerable part of this heat is wasted by way of ash sensible heat loss. The methods used for ash cooling include the water cooled ash screw system, the rolling cylinder ash cooler, fluidized bed ash cooler and the high strength steel belt ash cooler. In this study, the simulation of the performance of water based and air based ash cooling systems is done for a certain municipal waste fired boiler. The effect of the two methods on the overall boiler efficiency is studied. Comparison of results with that of a working system indicates that air cooling systems can be as efficient as the water cooled systems. With the help of this study, bottom ash heat recovery, especially for waste fired boilers, will be appreciated better and power plant designers will have a better insight into this area.
Discrete Topology Optimization of Structures Without Uncertainty
Authors: Zhou Hong , Kolavennu Surya Tej
Published: April 2014

The topology of a structure is defined by its genus or number of handles. When the topology of a structure is optimized, its topology might be changed if the material state of a design cell is switched from solid to void or vice versa. In discrete topology optimization, each design cell is either solid or void and there is no topology uncertainty from any grey design cell. Point connection might cause topology uncertainty and is eradicated when hybrid discretization model is used for discrete topology optimization. However, the topology solution of an optimized structure might be uncertain when its design domain is discretized differently, which is commonly called mesh dependence problem. In this paper, the degree of genus based topology optimization strategy is introduced to circumvent this topology uncertainty. With this strategy, the genus of an optimized structure is constrained during its topology optimization process. There is no topology uncertainty even if different design domain discretizations are used. The introduced strategy is used for discrete topology optimization of structures that have multiple loading points in this paper. The presented discrete topology optimization procedure is demonstrated by examples with different degrees of genus and loading conditions.
Corner Elimination in Discrete Topology Optimization of Compliant Mechanisms
Authors: Zhou Hong , Jangam Venkat S.
Published: April 2014

In discrete topology optimization, material state is either solid or void and there is no topology uncertainty caused by intermediate material state. A common problem of the current discrete topology optimization is that boundaries are unsmooth. Unsmooth boundaries are caused by the corners in topology solutions. Although outer corner cutting and inner corner filling strategy can mitigate corners, it cannot eliminate them. 90-degree corners are usually mitigated to 135-degree corners under the corner handling strategy. The existence of corners in topology solutions is because of the subdivision model. If regular triangles are used to subdivide a design domain, corners are inevitable in topology solutions. To eradicate corner from any topology solution, an innovative subdivision model is introduced in this paper for discrete topology optimization of compliant mechanisms. A design domain is discretized into quadrilateral design cells and every quadrilateral design cell is further subdivided into special triangular analysis cells that have a curved hypotenuse. With the presented subdivision model, all boundaries are smooth in any topology solution. Two discrete topology optimization examples of compliant mechanisms are solved based on the proposed subdivision approach.
A Moving Frame Method for Multi-Body Dynamics
Authors: Murakami H.
Published: April 2014

Élie Cartan’s moving frame method, developed in differential geometry, has been applied to multi-body dynamics to derive equations of motion. The explicit representation of a body-attached orthonormal coordinate basis and its origin, referred to as a moving frame, enables the usage of the special orthogonal group, SO(3), and the special Euclidean group, SE(3), to describe kinematics and kinetics of interconnected bodies by joints and force elements. The moving frame representation using Theodore Frankel’s compact notation is adopted to alleviate theoretical complexities of the Lie group theory to which SO(3) and SE(3) belong. For the variational formulation, the restricted variation of angular velocity is derived for the moving frame method.

Starting from two connected rigid bodies, it will be demonstrated that the explicit representation of moving frames renders straight-forward symbolic computations of three-dimensional kinematics and kinetics. This simplicity eliminates errors in computing analytical expressions for kinematic and kinetic variables and streamlines the coding effort for numerical solution. For controller design, if the degrees-of-freedom is small, the moving frame method allows a straight-forward derivation of equations of motion in analytical form.
A Mathematical Model for a Gyroscopic Ocean-Wave Energy Converter
Authors: Murakami H. , Rios O.
Published: April 2014

Global attempts to increase generation of clean and reproducible energy have contributed to considerable progress in ocean-wave power-generation technologies. The efficiency of ocean-wave energy converters has improved by almost an order of magnitude in the last decade. In this report, we consider a floating-type gyroscopic ocean-wave power-generator that has proven to generate 50 kW in a prototype test conducted by a Japanese company in 2012.

A gyroscopic power generator consists of a buoy, a gimbal, and spinning rotors mounted on a gimbal. The gimbal is installed on the deck of the buoy and rotates when the buoy oscillates or rocks by ocean waves. The gimbal axis is connected to an electric generator.

The objectives of our research are to understand quantitatively the mechanisms of gyroscopic ocean-wave power-generators and to improve the component design of the generator to maximize power output. To this end, we develop a mathematical model and a scale model of a gyroscopic ocean-wave power-generator. This integrated approach is to numerically simulate power generation and to clarify the effect of relevant design parameters.
Liquid Film Evaporation in the Presence of Micro Encapsulated Phase Change Materials: A Numerical Study
Authors: Khakpour Yasmin , Seyed-Yagoobi Jamal
Published: April 2014

This paper numerically investigates the flow and heat transfer characteristics of a slurry of micro encapsulated phase change materials (MEPCM) and R134a in the presence of film evaporation. The numerical domain is comprised of a minichannel in contact with a finite thickness solid zone with constant wall temperature. During the evaporation process, the concentration of MEPCM in the slurry increases, resulting in a continuous variation of effective thermal properties of the slurry. The effect of PCM concentration on the evolution of the liquid film thickness under different operating conditions along with the variation of the local heat transfer coefficients has been studied. A user defined function has been developed to incorporate the evaporation process by introducing the mass and energy source terms for the evaporation process as well as the variation of the MEPCM concentration along the channel.
An International Outlook of Innovative Energy Efficient Designs of Low Carbon Buildings
Authors: Khalil Essam E.
Published: April 2014

The Developing communities in their path for rapid development is endeavoring to make all necessary and appropriate measures to enhance the efficiency of energy utilization and increase the beneficiation of the energy resources. The energy production, transmission, distribution and utilization efficiency becomes a vital factor and measure of national development. Governmental organizations were established earlier to be responsible for energy planning and efficient utilization, information dissemination and capacity building as well as devising the necessary codes and standards. Throughout the Nation Energy resources are widely used and consumption rates are in general exceeding the International accepted values. Energy rationalization and audit exercises were developed and monitored by Governmental authorities, Universities and Research centers through the past two decades with a definitive positive energy reduction and beneficiation. The development of the relevant codes for Residential and Commercial Energy Efficiency in Building is underway through the governmental bodies responsible for the research and development in the building Technology sector and is the umbrella under which the National and Unified Arab Codes are developed and issued. A proposed new Energy Performance in Buildings Directive based on relevant ISO, ASHRAE and LEED would be beneficial to practitioners to meet the following targets of Energy Performance Directive:

1. “Legestilative authorities shall ensure that, when buildings are constructed, sold or rented out, an energy performance certificate should be made available to the owner.

2. The energy performance certificate for buildings shall include reference values such as currant legal standards and benchmarks in order to make it possible for consumers to compare and assess the energy performance of the building. The certificate shall be accompanied by recommendations for cost-effective improvement of the energy performance…”.Ultimately a unique energy standard is sought for Middle East region to harness the energy consumption. This can be achieved by developing methodologies for energy declaration of the buildings and to provide a labeling system and energy signature for selected buildings.