bluuebunny/crossref_metadata_2025 huggingface dataset:
F1 in Schools: An Australian Perspective
Authors: Smith Warren F. , Myers Michael , Dansie Brenton
Published: October 2013

The Australian Government and industry groups have been discussing the projected “skills shortage” for a number of years. This concern for the future is mirrored in many countries including the USA and the UK where the risk is not having sufficient skilled people to realise the projects being proposed. Growing tertiary qualified practicing engineers takes time and commitment but without the excitement of the possibility of such a career being seeded in the youth of the world, school leavers won’t be attracted to engineering in sufficient numbers.

In response, one successful model for exciting school children about engineering and science careers is the international F1inSchools Technology Challenge which was created in the UK in 2002 and implemented in Australia in 2003. It is now run in over 300 Australian Schools and 33 countries. In the Australian context, the program is managed and promoted by the Reengineering Australia Foundation. It is supported and fostered through a range of regional hubs, individual schools and some exceptional teachers. Presented in this paper are some perspectives drawn particularly from the Australian experience with the program over 10 years — which by any measure has been outstanding.

The F1inSchools model has been designed specifically through its association with Formula One racing to attract the intrinsic interests of students. It is based on the fundamentals of action learning. Role models and industry involvement are utilised as motivation modifiers in students from Years 5 to 12. While immersing children in project based learning, the program explicitly encourages them to engage with practicing mentors taking them on a journey outside their normal classroom experience. In this program, students have the opportunity to use the design and analysis tools that are implemented in high technology industries. Their experience is one of reaching into industry and creative exploration rather than industry reaching down to them to play in a constrained and artificial school based environment.

Anecdotally F1inSchools has been very successful in positively influencing career choices. With the aim of objectively assessing the impact of the program, doctoral research has been completed. Some key findings from this work are summarized and reported in this paper. The children involved truly become excited as they utilise a vehicle for integration of learning outcomes across a range of educational disciplines with a creative design focus. This enthusiasm flows to reflective thought and informed action in their career choice. As a result of F1inSchools, students are electing to follow engineering pathways and they will shape tomorrow’s world.
Numerical Simulations of Soluble Bubble Dynamics in Acoustic Fields
Authors: Volkova Ekaterina V. , Nasibullaeva Elvira S. , Gumerov Nail A.
Published: October 2013

Acoustic waves in liquids cause appearance, growth and dissolution of bubbles. Various physical and chemical effects related to bubble dynamics have been studied for a long time due to their importance for sonochemical reactors, acoustical cleaning, biomedical applications and more. One of the factors that may affect the self-organization of bubbles in acoustic fields and stable cavitation bubble formation is rectified diffusion. There exist approximate/asymptotic theories of rectified diffusion including a small amplitude approximation pioneered by Hsieh and Plesset and high radial Peclet number approximation of Fyrillas & Szeri, which do not take into account the influence of the small instantaneous mass change of the bubble on its dynamics. The goal of the present study is to check how these theories are good. For this purpose a numerical method based on the model of spherical bubble experiencing strong nonlinear oscillation in an isotropic acoustic field was developed and direct simulations were performed. Computations are accelerated using multicore CPU parallelization, which enable extensive parametric studies and validation of asymptotic methods via direct numerical simulation. Several cases were analyzed in details which show that the effect neglected in the previous studies may contribute to rectified diffusion (e.g. for micron size bubbles in the regime of sonoluminescence).
Numerical Investigation of the Pouring Process of Liquid From an Open-Top Hydrostatic Column
Authors: Sun Zhongguo , Liang Yangyang , Chen Xiao , Xi Guang
Published: October 2013

Liquid flows in a particular pattern and sequence when it is poured out from an open-top hydrostatic column. Since the liquid in the pouring process has a large deformation, conventional mesh-based method has difficulty in simulating. A meshless method, the moving particle semi-implicit (MPS) method, has been employed in this paper to calculate the unsteady flow with complex deformation. A modified solid-liquid boundary condition was verified and adopted with a new definition of static liquid layers. The hydrostatic column and the liquid inside were all discretized by identical particles but under different parameter values; the circular arc camber boundary condition is expressed accurately with particles by using cylindrical coordinate system. The pouring process is reproduced numerically and the flowing sequence of fluid is analyzed by tracking the fluid particles. The flowing sequence of the liquid can be calculated by restoring the liquid particles back to their initial positions before it is poured. The mass transfer property, liquid flowing sequence and even the flow rate were found to depend on the position of the rotation axis. The cases with typical rotational axis positions were calculated and analyzed. The character vortex which is generated by the rotation of the container in two-dimensional simulation in previous work dose not exist in the three dimensional simulation in this paper. The results reveal a principle for a versatile pouring process and may contribute to the applications of flowing control in many fields.
Determining Compatibility of Battery Storage Systems With Hybrid PV-Wind-Diesel Energy Systems
Authors: Roberts-Smith Da’Janel , Onyebueke Landon
Published: October 2013

Renewable energy is the only known source that can suffice the global demand in a sustainable way while preserving human and environmental health. Fossil fuels offer an unparalleled ability to robustly transform simple ideas into lucrative businesses and operations despite its inherent devastation imposed to the ecosystem and energy security. Together, fossil fuels, renewable energy and battery storage technology, offer great promise for an improved quality of life inclusive of global access to environmentally pristine, uninterrupted energy. Hybrid systems can be designed to deliver clean, portable energy cost-effectively, efficiently and reliably while minimizing present-day economic and environmental impact. An improvement in battery storage technology is of paramount importance to design an optimal hybrid system necessary to meet peak demands and compensate for intermittency within renewable energy resources. Various battery types have been developed as the technology of choice for renewable energy applications but compatibility issues of different battery systems to renewable energy sources remain. This study provides a comparative analysis of battery storage systems and introduces a mathematical model for a photovoltaic-wind-diesel hybrid system integrating optimization and performance techniques along with an economic analysis that will be used for further study and future simulation.
Study on Heat Transfer Characteristics of Loop Heat Pipe for Solar Collector
Authors: Sato Shota , Hirasawa Shigeki , Kawanami Tsuyoshi , Shirai Katsuaki
Published: October 2013

We experimentally study the thermal conductance of single-tube and loop heat pipes for a solar collector. The evaporator of the heat pipe is 1 m long, 6 mm in diameter and has 30° inclination. The thermal conductance is defined as the heat transfer rate divided by the temperature difference between the evaporator-wall and the condenser-wall. Effects of heat transfer rate, saturation temperature of the working fluid, liquid filling ratio, inclination angle, and position of the evaporator on the thermal conductance are examined. We found that the thermal conductance of the 30°-inclined loop heat pipe with an upper-evaporator is 40–50 (W/K), which is 1.8 times higher than that of the vertical loop type and 3 times higher than that of the single-tube type. Thus, the inclined loop heat pipe is preferable for a solar collector. There is an optimum liquid filling ratio. When the liquid filling ratio is too small, a dry-out portion appears in the evaporator. When the liquid filling ratio is too large, the liquid flows in the condenser to decrease heat transfer area. Also we numerically analyze the thermal conductance of a vertical loop heat pipe.
Robust Design and Geometry Assurance Considering Assembly Ergonomics
Authors: Rosenqvist M. , Falck A.-C. , Söderberg R.
Published: October 2013

The objective of this study was to explore how assembly ergonomics issues were regarded by geometry engineers. Therefore, 21 geometry engineers in two manufacturing companies were interviewed. Their answers show good awareness of the implications of poor assembly ergonomics but appropriate working procedures and support in CAT (Computer Aided Tolerancing) tool are missing. 95% of the respondents would like to add consideration to assembly ergonomics in their CAT simulation. Based on this study a number of assembly factors that need to be included and considered in locating scheme definition and geometric stability analysis are identified and presented. Altogether, the results show a need for organizational change and CAT tool development.
Experimental Study of Human Walking to Running Dynamics With Applications to Energy Harvesting
Authors: Ballard Zach , Mann Brian P.
Published: October 2013

The nonlinear dynamics of a runner are reported here. Image processing software is used obtain experimental data of the 2-D leg motion of the athlete. The available power that the athlete creates from this motion is calculated for multiple speeds. The multi-frequency motion is then filtered, recreated numerically, and compared to the experimental data. This entire process is repeated for multiple athletes of different backgrounds and skill levels. The frequencies at which large amounts of power are available are compared for each athlete in order to find any possible commonality.
Investigation of a MEMS-Based Boiler and Free Piston Expander for Energy Harvesting
Authors: Champagne C. , Weiss L.
Published: October 2013

Initial investigations of a small-scale Free Piston Expander (FPE) are presented. In final form, the FPE will be a MEMS-based device capable of operation from low temperature waste heat sources. In this present study, a millimeter scale device is constructed and tested to yield insight into critical operational parameters.

Different constructions and operating conditions are considered as are the effects on basic piston motion and performance. These include piston length and mass. In addition, different sealing and lubricating fluids are considered. Construction of this testbed device is via concentric copper tubing, allowing an effective baseline study of these determining parameters.

Results show that, while thick lubricants seal well in a static test, piston motion is decreased in a dynamic test indicating leakages. By contrast, reduced viscosity lubricants dont seal as well in a static test, but yield increased piston motion in dynamic testing. This indicates effective sealing. The trends established by the study of varying viscosity lubricants hold true for pistons of increasing mass and length as well. A mixture of isopropanol and water performed well in these tests, and represented a low viscosity sealing fluid. Compared to conditions where no lubricant was used, maximum velocity was increased up to 50%. These results indicate that a thin, wetting fluid will be the best lubricant for the FPE, due to increased sealing and performance when in dynamic operation.
Propagation of Guided Waves in Pressure Vessel and its Application for Damage Detection
Authors: Sun Xuewei , Li Fucai , Wang Jinfu , Meng Guang , Zhou Limin
Published: October 2013

Pressure vessel is a kind of special equipment with explosion and leakage dangerous. Therefore, structural health monitoring (SHM) techniques for pressure vessel should ensure the safe operation of this kind of equipments and is becoming more crucial in petroleum, chemical, and relative industries. Guided wave-based structural health monitoring technique can be an appropriate method for real-time and online non-destructive damage monitoring technique. In recent years, applications of guided wave-based structural health monitoring techniques are mainly limited in simple structures, such as plates and tubes. Relatively few research papers focused on the application of this technique in large and complex structures like pressure vessels.

Propagation characteristics of guided waves in pressure vessel are investigated in this study. Dispersion curves calculated by using numerical methods for longitudinal, circumferential, and torsional modes are presented. On the basis of comprehensive analysis of the guided waves dispersion and experimental waveforms, the parameters of the excitation wave are therefore optimized. In order to overcome the difficulties to identify the damage characteristics of signal, the layout scheme of sensor network is designed and optimized in this paper to simplify the waveform.

Furthermore, both finite element analysis (FEA) and experiment methods are employed to investigate the propagation of elastic guided waves in a standard pressure vessel.
Nonlinear Instability Analysis of an Annular Swirling Viscous Liquid Sheet
Authors: Yan Kai , Jog Milind A. , Ning Zhi
Published: October 2013

A nonlinear spatial instability analysis of an annular swirling viscous liquid sheet has been carried out by a perturbation expansion method with the initial amplitude of the disturbance as the perturbation parameter. The viscous liquid sheet is considered to move axially and azimuthally and is exposed to co-flowing inner and outer gas streams. The effects of liquid swirl strength and liquid viscosity on the sheet instability and breakup length have been studied. The results show that except at very low values of swirl to axial velocity ratio of the liquid sheet, the liquid swirl destabilizes the sheet. The sheet breakup length increases slightly and then decreases rapidly with an increase in liquid swirl strength. Viscosity has a stabilizing effect on the sheet breakup. The sheet breakup length increases with an increase in liquid viscosity.
Event-Based Temperature Control for Machining Using MTConnect
Authors: Malik Subhasish , Bedillion Mark D.
Published: October 2013

MTconnect is a newly-developed standardized communications protocol that is designed to make it easier to collect, transmit and leverage data from shop floor machine tools. However, MTConnect is a read-only architecture, i.e., it is currently used for monitoring and not control of manufacturing processes. This paper develops an event-based real-time control architecture using MTConnect and demonstrates feasibility on tool-tip temperature control of a small-scale CNC prototype machine. Analytical modeling provides a link between tool feed rate and tool-tip temperature. This model, which is verified through experiments, is used to develop both periodic sampling and eventbased PID control laws. The periodic PID controller is implemented on device to serve as a performance benchmark. Its performance is compared, both in simulation and experimentally, to an MTConnect-enabled event-based controller operating over the web.
Design, Installation, and Performance Characterization of a Laboratory-Scale Solar Thermal System for Experiments in Solar Energy Utilization
Authors: Drozek Stephanie , Damm Christopher , Enot Ryan , Hjortland Andrew , Jackson Brandon , Steffes Benjamin , Rode Kevin
Published: October 2013

The purpose of this paper is to describe the implementation of a laboratory-scale solar thermal system for the Renewable Energy Systems Laboratory at the Milwaukee School of Engineering (MSOE). The system development began as a student senior design project where students designed and fabricated a laboratory-scale solar thermal system to complement an existing commercial solar energy system on campus. The solar thermal system is designed specifically for educating engineers. This laboratory equipment, including a solar light simulator, allows for variation of operating parameters to investigate their impact on system performance. The equipment will be utilized in two courses: Applied Thermodynamics, and Renewable Energy Utilization. During the solar thermal laboratories performed in these courses, students conduct experiments based on the American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) 93-2010 standard for testing and performance characterization of solar thermal systems. Their measurements are then used to quantify energy output, efficiency and losses of the system and subsystem components.
Sodium Nickel Chloride Battery Design and Testing
Authors: Frutschy Kris , Chatwin Troy , Mao Leng , Smith Chris R. , Bull Roger
Published: October 2013

The main subsystems in a GE Durathon™ sodium nickel chloride battery are cells, Battery Management System (BMS), and packaging (see Figure 1). This cell chemistry requires an internal operating temperature of about 300°C, which provides unique challenges for battery thermal insulation and cooling. Electrical insulation between the cells and enclosures is another challenge, because traditional polymer-based insulations cannot operate at this elevated temperature range. Similarly, mechanical support structures must be high-temperature capable and also provide adequate protection to the cells and BMS during abusive loading conditions.

This paper covers the basic battery design, thermal management, and the testing that has been conducted to ensure reliable and safe performance. Reliability testing includes battery mechanical shock and vibration plus accelerated life tests on specific components such as the heater.
Droplet Evaporation and Chemical Reaction in a Single Multi-Component Droplet to Synthesis Mixed-Oxide Film Using Spray Pyrolysis Method
Authors: Khatami S. M. Navid , Ilegbusi Olusegun J.
Published: October 2013

This paper describes mathematical modeling of transport and chemical reaction phenomena in a single droplet on a heated substrate deposited by spray pyrolysis. The droplet contains mixed salt solution which reacts on the heated substrate to produce mixed oxides and water residue. The water is subsequently evaporated, leaving a thin film of the mixed oxides for sensor application. The droplet, containing solvent and precursors is modeled using Computational Fluid Dynamics (CFD) technique. The variety of stages is predicted of the evolution of droplet morphology associated with surface energy and evaporation. The transient distribution is also predicted of the concentration of various species in the droplet.
Explaining Exergy: A Cycle Approach
Authors: Boettner Daisie D. , Benson Michael J. , Bluman James E. , Van Poppel Bret P. , Arnas A. Őzer
Published: October 2013

The exergy of a system at a given state traditionally is defined as the maximum potential useful work available from the system as it reaches equilibrium with its surroundings or a specified state (dead state). Boettner, et al. [1] demonstrate consideration of work required to restore the system to its original state is inherent in the definition of exergy. They provide a visual interpretation for the concept of exergy of a closed system whose temperature and pressure are above those of the dead state: closed system exergy corresponds to the sum of net work associated with a power cycle and a heat pump cycle with both cycles incorporating the system state and the dead state. On further investigation, the second cycle is not limited to a heat pump cycle and can be modeled as either a power cycle or a refrigeration/heat pump cycle. This paper simplifies the analysis such that one can immediately graph on a pressure-volume diagram and a temperature-entropy diagram a cycle whose enclosed area represents the exergy of a closed system at state i interacting with its surroundings (dead state). This paper also examines the case in which the closed system temperature and pressure are below those of the dead state.
Modeling and Optimization of an In-Plane Rotary Microactuator With Thermal Unimorph
Authors: Yang Fan , Lei Nan , Chen Xiaolin , Yang Jiaping
Published: October 2013

In this paper, design modeling of an in-plane rotary microactuator with electro-thermal unimorph is conducted. The electro-thermal unimorph is made of confined polymers consisting of a silicon skeleton filled with SU-8 photoresist. Due to the effect of thermal expansion mismatch between silicon and SU-8, the composite unimorph bends laterally when thermally activated. Numerical studies are carried out to investigate the effects of the silicon/SU-8 composite microstructure on the unimorph deflection. Unimorph dimensions are optimized to generate a large displacement at the cantilever tip. The microactuator device is comprised of four identical unimorphs and a suspended central platform. When thermally actuated, the displaced unimorphs can rotate the central platform bi-directionally in the platform plane. Finite element models of the microactuator device are built to investigate the device performance. A new device layout with a detached central platform structure is proposed to increase the rotational angle while maintaining a reasonable operating temperature. Our results show that the optimized microactuator can achieve a rotational angle of 4 degrees under a small actuating voltage input of 1V.
Simulation of Blank Design for Blades of Francis Turbines
Authors: Feng Zhengkun , Champliaud Henri , Sabourin Michel , Morin Sebastien
Published: October 2013

The metal pressing process which is widely used in many industries has advantages over casting process for producing large and thick blades of Francis turbine. For the design of pressing process, blank design should be firstly performed to determine the dimension of the flat blank. In fact, the traditional trial and error approach is not applicable for the blade design for Francis turbines that is not standard because of the different hydraulic characteristics of a hydropower plant from site to site. The powerful computing technology makes it possible to desgn optimum blanks by numerical modeling and simulation. In this paper, the multi-step inverse finite element approach is investigated for blank design and an elasto-plastic model has been built by using the well-known software ANSYS. Unfolding tests with cylindrical sections have been carried out and the numerical results agree well with the analytical results. Thereafter, a large and thick blade of Francis turbine for hydropower plants has been successfully unfolded by the FE model. Finally, for ensuring the machining of the blade after the pressing process, a new contour is obtained by extending the boundary of the flat blank provided by the FE model.
A New Energy Optimization Strategy for Pumping Operation in Water Distribution Systems
Authors: Al-Ani Dhafar , Habibi Saeid
Published: October 2013

As time goes on, more and more operating-modes based on changing demand profiles will be compiled to enrich the range of feasible solutions for a water distribution system. This implies the conservation of energy consumed by a water pumping station and improves the ability for energy optimization. Another important goal was improving safety, reliability, and maintenance cost. In this paper, three important goals were addressed: cost-effectives, safety, and self-sustainability operations of water distribution systems. In this work, the objective functions to optimize were total electrical energy cost, maintenance costs, and reservoir water level variation while preserving the service provided to water clients. To accomplish these goals, an effective Energy Optimization Strategy (EOS) that manages trade-off among operational cost, system safety, and reliability was proposed. Moreover, the EOS aims at improving the operating conditions (i.e., pumping schedule) of an existing network system (i.e., with given capacities of tanks) and without physical changes in the infrastructure of the distribution systems. The new strategy consisted of a new Parallel Multi-objective Particle Swarm optimization with Adaptive Search-space Boundaries (P-MOPSO-ASB) and a modified EPANET. This has several advantages: obtaining a Pareto-front with solutions that are quantitatively equally good and providing the decision maker with the opportunity to qualitatively compare the solutions before their implementation into practice. The multi-objective optimization approach developed in this paper follows modern applications that combine an optimization algorithm with a network simulation model by using full hydraulic simulations and distributed demand models. The proposed EOS was successfully applied to a rural water distribution system, namely Saskatoon West. The results showed that a potential for considerable cost reductions in total energy cost was achieved (approximately % 7.5). Furthermore, the safety and the reliability of the system are preserved by using the new optimal pump schedules.
A Micromachined Contactless Suspension With Zero Spring Constant
Authors: Poletkin Kirill
Published: October 2013

In this paper, a micromachined contactless suspension with a zero spring constant that provides possibility to significantly increasing sensitivity of micromachined sensors is studied. Minimization of the spring constant of the contactless suspension is achieved by combining inductive and electric contactless suspensions. In particular, the conditions required to eliminate the spring constant of the suspension and achieve stable levitation of the disk shaped proof mass are obtained based on the analysis of developed mathematical model of the suspension. It is shown that such a suspension can be developed in principle.
Design Uncertainty Effects Quantification Using Monte Carlo Simulation
Authors: Kamel Hesham
Published: October 2013

This paper presents an approach to evaluate the effect of uncontrolled and un-avoided variation within design variables on the performance of nonlinear finite element models. The approach employs Monte Carlo simulation to reveal this effect using descriptive statistics to present useful information to the designer. A case study of a thin walled tube under dynamic impact loading is used to demonstrate the proposed approach. The thin walled tube is modeled using LS-DYNA for finite element simulation. Wall thickness distributions are selected as design variables where the amount of impact energy absorbed, maximum rigid wall force and final deformation are selected as the important responses. The results clearly show that the proposed approach can provide the designer with useful information of the effect of variation within the design variables on the structure responses. Ultimately, the designer can use this helpful information in creating a design that is minimally sensitive to those uncontrolled and un-avoided variation within design variables.
Comparison of Piezoelectric Structural Damping Based on Velocity Controlled Switching and Pulse Width Modulation Switching Circuits
Authors: Vasic Dejan , Liu Yuan-Ping , Costa François
Published: October 2013

Two novel piezoelectric damping techniques (VSD and PWMD) are compared in this paper to the traditional resonant shunt damping technique and SSDV technique. In VSD, the switching shunt circuit turns ON or OFF according to the polarity of the vibration velocity of the host structure to shift the piezoelectric voltage phase. An external voltage source is connected to enlarge the voltage amplitude across the piezoelectric element and to optimize the dissipated power. The PWM shunt technique not only can decrease the audible noises more efficiently but also ensure the stability of the control system with a constant voltage source. The theoretical and the experimental results show that the piezoelectric voltage can be adaptive to the vibration displacement by the pulse widths variation, so the PWMD can stay in stable state with a constant voltage source and can still provide a very good performance.
Development of Transparent Conductive Single-Walled Carbon Nanotubes Films
Authors: Kok E. , Tey J. N. , Wei J.
Published: October 2013

In our research, we aim to formulate SWNTs ink and develop a methodology to create enhanced conductive flexible transparent SWNTs films that have the potential to possibly reduce the use of ITO. In our preliminary findings, we achieved a sheet resistance of 25.1 kΩ/sq with ∼93% transparency (excluding film) by spraying a unsorted purified pristine SWNTs. In-house separated M-SWNTs, prepared using agarose gel separation methods, were sprayed with sheet resistance of 3.3 kΩ/sq and ∼86% transparent.. Investigation of tube length with respect to conductivity was also studied — nanotubes were sonicated for different durations (thus affecting tube length) before separation and spraying.
Development of a High-Performance Fluid Infrared Temperature Measurement System
Authors: Chang H. , Wang M. R. , Wei J. , Wei Z.
Published: October 2013

In this paper, a high-performance fluid infrared temperature measurement system without the need for “radiance correction” through an analysis of liquid fluid properties was proposed based on the Blackbody Radiation Theory and Max Planck’s Quantum Theory. In terms of practical application, the system can be calibrated by a high-precision contact-type thermodetector at a time. Then, the resulting data were fitted to complete a continuous curve to meet the measured temperature variation of the liquid fluid. Accordingly, the precise temperature is measured. A higher pertinence of the system makes it easier for a real-time liquid temperature monitoring with accuracy up to 0.1%. This method can also be extended to other non-contact temperature measurement field.
The Effect of the Sulcus Morphology on the Transduction of Impacts to the Brain
Authors: Saboori Parisa , Sadegh Ali
Published: October 2013

The human head, being a vulnerable body region, is most frequently involved in traumatic brain injuries (TBI) and life threatening injuries. Accurate modeling of the variability of the brain morphology is a fundamental problem in investigating TBI. Improved computational/mathematical structural models of the brain are needed to help investigators to have a better understanding of the phenomena of different traumatic brain injuries such as concussion. The human brain is the most complex region of the body. There is a very thin membrane known as a pia mater that covers all the surface of the brain. The pia mater follows all the fissure of the brain and covers all the surface of the sulci and gyri. Sulcus is referred to any furrow in the brain. Statistically there are about 72 main sulci in the human brain. Previous FE studies of TBI have ignored sulcus morphology in their modeling and thus, their results could be unreliable.

In this paper, the effect of the brain sulcus structure on mechanotransduction of impacts to the brain has been investigated. This was accomplished by using series of parametric studies and comparing the results with the model without sulci. The results of this study reveal that the brain’s strain is reduced in the present of sulcus and gyrus structures. We have hypothesized that the presence of sulcus increases the surface area of the brain thereby decreases the normal and shear strain in the brain. That is, the presence of sulcus and gyrus reduce the transduction of the external load and impacts to the white and gray matters of the brain and thereby reduces the risk of TBI. Ignoring sulci in any FE modeling and analysis of the brain may lead to unreliable results.
Design and Analysis of a Series Hybrid Electric Vehicle for Indian Conditions
Authors: Kumar C. S. Nanda , Subramanian Shankar C.
Published: October 2013

Electric and hybrid vehicles are emerging rapidly in the automotive market as alternatives to the traditional Internal Combustion Engine (ICE) driven vehicles to meet stringent emission standards, environmental and energy concerns. Recently, Electric Vehicles (EVs) and Hybrid Electric Vehicles (HEVs) have been introduced in many countries including India. One configuration of a HEV is the Series Hybrid Electric Vehicle (SHEV). The design and analysis of the drive system of a SHEV under Indian conditions is the focus of this paper. In conventional vehicles, the ICE is the power source that drives the vehicle. The energy from the ICE is distributed to the wheels through the transmission, which is then used to generate the traction force at the tyre-road interface. In a HEV, both the engine and the electric motor provide the energy to drive the vehicle. In a SHEV, the energy generated by the electric motor is transmitted through the transmission to meet the torque demand at the wheels. Based on the driver’s acceleration demand and the state of charge of the battery, the controller manages the ICE, the generator and the battery to supply the required energy to the motor. The motor finally develops the required drive torque to generate the traction force at the wheels to meet the vehicle drive performance requirements like gradeability, acceleration and maximum speed. The objective of this paper is to discuss the design of the drive system of a SHEV. This involves the calculation of the power specifications of the electric motor based on the vehicle drive performance requirements. The equations for performing these calculations are presented. The procedure is then demonstrated by considering a typical Indian commercial vehicle along with its typical vehicle parameter values. A simulation study has also been performed by considering the Indian drive cycle to demonstrate the energy savings obtained by the use of a SHEV.
Velocity Oscillation and Pressure Drop in Water–Air Slug Flow
Authors: Yamamoto Ken , Ogata Satoshi
Published: October 2013

Visualization and pressure drop measurements of water–air two-phase flow in circular microchannels (d = 486 μm) was conducted. In order to investigate effects of the flow rates and T-junction size on the pressure drop of the two-phase slug flow, three test channels containing various T-junctions (136, 194, and 252 μm) were prepared. The measured pressure drop was compared with the results from semi-empirical model and theoretical model, and it was found that the experimental data generally agreed with the theoretical model. However, the pressure drop increased as the T-junction size decreased. In order to detect the causes of this increase in pressure drop, effects of the velocity fluctuation on the pressure drop were investigated. The velocity fluctuations were measured from the recorded images that were obtained by a high-speed camera. Although it was found that the instantaneous velocity fluctuated in large amplitudes and its cycle was synchronized with a period of the bubble pinch-off, the effects of the velocity fluctuation were negligible on the pressure drop. Finally, from a scaling analysis, it was suggested that the bubble overpressure was the cause of the increase in pressure drop.
Feasibility Study for Increasing the Efficiency of the Volute Casing in Air-Handling Centrifugal Machine Using Genetic Algorithm
Authors: Mohite Arvind S. , Nanavati J. I.
Published: October 2013

It is important to recognize that, the design of any turbo machine include many static and dynamic conditions, which are directly or indirectly related with the efficiency of the machine. Though centrifugal fans/blowers have been developed as highly efficient machines, design is still based on various empirical rules proposed by designers. Thus the design methodology suggested by different researchers differs widely to one another. The objective of present study is to combine & optimize those designs in order to yield an efficient design which gives desired performance. In centrifugal machines there is transfer and transformation of energy. Therefore it is challenging task to optimize the performance of machine. The design variables are iterated to satisfy the constraints. This is needed to achieve acceptable design. Almost all well-known references were referred before selecting constraints which limits the theoretical design. The constraints selected here are the outcomes of the work done by various researchers over many years. The new optimized design shows almost 10% increase in efficiency. The end results substantiate the present design and optimization methodology as a promising tool to a design engineer. Through analysis and comparison between combined heuristic optimization and Genetic Algorithms and the optimized design and the initial design, the validity and feasibility of the developed optimization design system is confirmed. Finally, results shows efficiency with power saving.
Optical Validation of Ejector Flow Characteristics Predicted by Computational Analysis
Authors: Little Adrienne B. , Bartosiewicz Yann , Garimella Srinivas
Published: October 2013

Passive, heat actuated devices can offer simple and energy-efficient options for a variety of end uses. An ejector pump is one such device that provides reasonable pressure head with no electrical input or moving parts. Useful for a wide range of applications from nuclear reactor cooling to vapor compression in waste-heat-driven heat pumping and work recovery systems, the flow phenomena inside an ejector must be understood to achieve improvements in component design and efficiency. In an effort to obtain insights into the flow phenomena inside an ejector, and to evaluate the effectiveness of commonly used computational tools in predicting these conditions, this study presents a set of shadowgraph images of flow inside a large-scale air ejector, and compares them to computational simulations of the same flow. On-design and off-design conditions are considered where the suction flow is choked and not choked, respectively. The computational simulations used for comparison apply k-ε RNG and k-ω SST turbulence models available in ANSYS FLUENT to 2D, locally-refined rectangular meshes for ideal gas air flow. Experimental and computational results show that on-design ejector operation is predicted with reasonable accuracy, but accuracy with the same models is not adequate at off-design conditions. This is attributed to an inability of turbulence models to predict shock/expansion interaction with the motive jet boundary, as well as the strength and position of flow features. Exploration of local flow features shows that the k-ω SST model predicts the location of flow features, as well as global inlet mass flow rates, with greater accuracy. It is concluded that to provide a rigorous validation of turbulence models for the application of modeling ejector flow, it is necessary to rely on off-design data where more complex phenomena occur, such as flow separation, strong boundary layer/shock interaction, and unsteady flow. Such validation will help refine turbulence models for future ejector design purposes, and allow for more efficient ejector operation.
CoNNECT: Data Analytics for Energy Efficient Communities
Authors: Omitaomu O. A. , Bhaduri B. L. , Maness C. S. , Kodysh J. B. , Noranzyk A. M.
Published: October 2013

Energy efficiency is the lowest cost option being promoted for achieving a sustainable energy policy. Thus, there have been some innovations to reduce residential and commercial energy usage. There have also been calls to the utility companies to give customers access to timely, useful, and actionable information about their energy use, in order to unleash additional innovations in homes and businesses. Hence, some web-based tools have been developed for the public to access and compare energy usage data. In order to advance on these efforts, we propose a data analytics framework called Citizen Engagement for Energy Efficient Communities (CoNNECT).

On the one hand, CoNNECT will help households to understand (i) the patterns in their energy consumption over time and how those patterns correlate with weather data, (ii) how their monthly consumption compares to other households living in houses of similar size and age within the same geographic areas, and (iii) what other customers are doing to reduce their energy consumption. We hope that the availability of such data and analysis to the public will facilitate energy efficiency efforts in residential buildings. These capabilities formed the public portal of the CoNNECT framework. On the other hand, CoNNECT will help the utility companies to better understand their customers by making available to the utilities additional datasets that they naturally do not have access to, which could help them develop focused services for their customers. These additional capabilities are parts of the utility portal of the CoNNECT framework.

In this paper, we describe the CoNNECT framework, the sources of the data used in its development, the functionalities of both the public and utility portals, and the application of empirical mode decomposition for decomposing usage signals into mode functions with the hope that such mode functions could help in clustering customers into unique groups and in developing guidelines for energy conservation.
Reduced Aerodynamic Drag for Truck-Trailer Configurations Using Parametrized CFD Studies
Authors: Pavlović Srdan , Andersson Magnus , Lantz Jonas , Karlsson Matts
Published: October 2013

In the presented work, two studies using Computational Fluid Dynamics (CFD) have been conducted on a generic truck-like model with and without a trailer unit at a speed of 80 km/h. The purpose is to evaluate drag reduction possibilities using externally fitted devices. A first study deals with a flap placed at the back of a rigid truck and inclined at seven different angles with two lengths. Results show that it is possible to decrease drag by 4%. In a second study, the flap has been fitted on the tractor and trailer units of a truck-trailer combination. Four settings were surveyed for this investigation, one of which proved to decrease drag by up to 15%. A last configuration where the gap between the units has been closed has also been evaluated. This configuration offers a 15% decrease in drag. Adding a flap to the closed gap configuration decreases drag by 18%. New means of reducing aerodynamic drag of heavy-duty (HD) vehicles will be important in the foreseeable future in order to improve the fuel economy. The possibilities of reducing drag are prevalent using conceptual design.
Development of a Sustainable System Emulator for Living Environments Powered by Renewable Energy
Authors: Endo Mitsuru , Kakizaki Takao , Nagasawa Kazunori
Published: October 2013

In the present paper, a sustainable system emulator (SSE) for living environments powered by renewable energy sources is addressed. The main purpose of the SSE is to emulate the various factors that influence sustainability using a simple engineering approach. The main goal is to realize a useful mixed-reality platform for designing living environments with overall energy self-sufficiency as well as adequate habitability. The SSE design concept is based on the combination of an outer-system emulator (OSE) and an inner-system emulator (ISE). The OSE uses artificial lights and air blowers to emulate the sunshine and wind conditions in the Fukushima area of Japan. The ISE emulates the interior of a residential environment, based on renewable energy sources and power storage facilities, and consists of reduced-scale models powered by solar cells and a wind turbine. The ISE also includes DC appliances, which emulate domestic power usage, and electrochemical batteries for power storage. Control algorithms for energy management can also be implemented in the SSE. An experimental study was carried out using the SSE to emulate both the natural environment and living environments, and the relationship among the different emulation parameters was investigated. Furthermore, the experimental results indicated that accelerated testing using SSE may be effective for improving the design efficiency of renewable-energy powered systems.
Multi-Point Positioning Method for Flexible Tooling System in Aircraft Manufacturing
Authors: Liu Chunqing , Hong J. , Wang Shaofeng
Published: October 2013

In the field of aircraft manufacturing, the conventional six-point location principle and relevant process equipment and technology can hardly meet the requirements of high efficient and high precision machining of large-scale thin-walled workpieces. To solve positioning problems of aircraft large-scale thin-walled workpieces in its machining and assembly process, a flexible positioning tooling system is appeared and based on which the multi-point positioning method is developed to optimize the number, location and clamping force of the vacuum heads of flexible tooling system. By numerical simulation, an example is presented to verify the effectiveness of the positioning optimization method. Finally, numbers of experiments for thin-walled workpieces were carried out to validate the positioning optimization method and the numerical example. Test data show that the FEA method used in this paper can accurately reflect the deformation of the workpiece, and the deformation of the workpiece after positioning is minimized and the stiffness is maximized with the positioning optimization method when using flexible positioning tooling system.
Thermal Measurement System for Phase Change Materials
Authors: Adinberg R. , Zvegilsky D.
Published: October 2013

A lab scale set-up designed based on reflux heat transfer is used for studying latent heat storage for concentrating solar power systems. Phase change materials (PCM) with temperature of fusion range between 300 and 400°C are being tested using this system, including metal alloys and inorganic salts. In the present configuration, the system provides thermal measurements of PCM specimens of about 1000 g under heating temperature up to 450°C and enables simultaneous studying calorimetric properties of the loaded materials and heat transfer effects developed in the thermal storage process composed of charge and discharge phases. The measurement technique includes a thermal analysis model aimed at evaluating the experimental data. Results of the thermal measurements conducted with a thermal storage medium composed of potassium nitrate KNO3 (m.p. 334°C) as PCM and Diphyl (synthetic thermal oil, max working temperature 400°C) as the heat transfer fluid are presented and discussed in this study.
Coexisting Asymmetric and Symmetric Periodic Motions in the Mathieu-Duffing Oscillator
Authors: O’Connor Dennis , Luo Albert C. J.
Published: October 2013

In this paper, periodic motions in the Mathieu-Duffing oscillator are analytically predicted through the harmonic balance method. The approximate, analytical solutions of periodic motions are achieved, and the corresponding stability analyses of the stable and unstable periodic solutions are completed. Numerical simulations are provided for a complete picture of coexisting periodic motions.