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2017-12-08
Paper
SN-0003
Small tactical UAVs (SUAVs) have made their mark in military operations with their ability to gather and provide localized, real-time information. Typical uses include perimeter surveillance of remote military compounds, over-the-horizon surveillance, and remote monitoring of critical logistics routes. However, their potential to take on increased and increasingly complex missions is hampered by their limited endurance. This work explores research done under the auspices of the European Commission’s Fuel Cell and Hydrogen Joint Undertaking on a fuel cell and battery hybrid energy storage system that could increase the total amount of onboard energy storage, while continuing to deliver the peak power needs of the SUAV.
2017-11-15
Journal Article
2017-32-0119
Akira Iijima, Takuya Izako, Takahiro Ishikawa, Takahiro Yamashita, Shuhei Takahata, Hiroki Kudo, Kento Shimizu, Mitsuaki Tanabe, Hideo Shoji
Engine knock is the one of the main issues to be addressed in developing high-efficiency spark-ignition (SI) engines. In order to improve the thermal efficiency of SI engines, it is necessary to develop effective means of suppressing knock. For that purpose, it is necessary to clarify the mechanism generating pressure waves in the end-gas region. This study examined the mechanism producing pressure waves in the end-gas autoignition process during SI engine knock by using an optically accessible engine. Occurrence of local autoignition and its development process to the generation of pressures waves were analyzed under several levels of knock intensity. The results made the following points clear. It was observed that end-gas autoignition seemingly progressed in a manner resembling propagation due to the temperature distribution that naturally formed in the combustion chamber. Stronger knock tended to occur as the apparent propagation speed of autoignition increased.
2017-11-13
Tech Insights
TI-0002
While all-electric aircraft remain at the bleeding edge of the aviation industry, incorporating technologies like proton exchange membrane fuel cells into existing aircraft can result in considerable auxiliary capability with low environmental impact. However, proper consideration must be given to supporting systems to achieve a reliable balance of plant-especially when those systems interface with existing aircraft architectures. The scope of the BoP is to manage and condition the reactant flows to and from the fuel-cell module and to provide power to system components.
2017-11-05
Technical Paper
2017-32-0033
Akinori Shinagawa, Hisayuki Nozawa, Yutaro Uchiyama
Two-wheeled off-road vehicles are mainly ridden on slippery dirt roads that include steep slopes and rough, uneven surfaces. An analysis method for the driving state and the vehicle movement limits that would be suitable for analyzing the movement of such two-wheeled off-road vehicles under these conditions was examined. These movement limits were then formulated by taking into consideration the coefficient of friction and the road surface gradient in accordance with the basic laws of physics and also by focusing on the vehicle movement in the longitudinal direction. Measurements were also taken during actual off-road riding by top-class Japanese off-road motorcycle riders. It was confirmed that this measurement data was distributed within the range of the assumed vehicle movement limits. Consequently, it was confirmed that it is possible to use such measurements to accurately grasp the vehicle movement limits and the associated driving state for two-wheeled off-road vehicles.
2017-11-05
Technical Paper
2017-32-0047
Tomoaki Yatsufusa, Keigo Kii, Kentaro Takatani, Shinsuke Miyata
Multiple ion-probes method has an advantage for detailed measurement on high-intensity combustion including engine combustion, oscillation combustion in gas turbine or burner. Multiple ion-probes are installed individually on the surface of the confinement wall in combustion chamber. Detailed behavior of the flame propagation along the chamber wall can be reproduced by the datasets of the flame arrival time detected by individual ion-probes. Main target of this study is to clarify the measurement performance of this multiple ion-probes method for various type of propagating flames generated in confined combustion tube. The characteristics of the flame is largely varied by changing the ratio of dilution with nitrogen on methane-oxygen stoichiometric mixture. No dilution, which means methane-oxygen stoichiometric mixture only, results fastest speed and relatively stable propagation.
2017-11-05
Technical Paper
2017-32-0113
Daijiro Ishii, Hiromi Saito, Yuji Mihara, Yasuo Takagi
In order to establish standard method to evaluate cooling loss in combustion chamber of internal combustion engines based on measurement of instantaneous heat flux / wall temperature with higher response and accuracy than previously reported coaxial type thin-film temperature sensor by applying thin film fabrication technology based on PVD method (Physical Vapor Deposition method) which improved to realize higher responsiveness than the conventional sensor was developed by the authors, and it was confirmed that the sensor has sufficient durability in conditions in which the hydrogen jet and flame directly contacts surface of the sensor by thin-film material change. The influence of the improvement on the measurement accuracy was verified by numerical analysis including thermoproperty evaluation. In this report, the configuration of measurement system that can measure minute voltage from the sensor with low noise and high response is reported.
2017-11-05
Technical Paper
2017-32-0126
Huynh Thanh Cong, Takahiro Kashima, Daisuke Komasaki, Yuta Saito, Akihiko Azetsu
To explore the production and oxidation characteristics of soot in the flame of diesel jet under the condition equivalent to the direct injection diesel engine condition, the effect of three different important parameters (including injection pressure, injection duration, and oxygen concentration) are experimentally examined. For these purposes, a small CVCC (constant volume combustion chamber) with the volume of 60cc equivalent to the volume of combustion chamber of automotive diesel engine is used. To obtain the experimental data of soot production and oxidation, in experiments, the ambient condition of temperature, pressure and oxygen concentration before injection timing are prepared by the combustion of lean hydrogen mixture (with help of 8 spark plugs) at a high temperature and pressure condition around 1000K and 4.5MPa. The common rail type injector with 8 injection holes for modern diesel engine is attached to this vessel.
2017-11-05
Technical Paper
2017-32-0095
Preechar Karin, Warawut Amornprapa, Phiranat Khamsrisuk, Pol-ake Budsayahem, Pattara Chammana, Kobsak Sriprapha, Katsunori Hanamura
The soot contamination in used engine oils of diesel engine vehicles was about 1% by weight. The soot and metal wear particle sizes might be in the range of 0-1 µm and 1-25 µm, respectively. The characteristics of soot affecting on metal wear was investigated. Soot particle contamination in diesel engine oil was simulated using carbon black. Micro-nanostructure of soot particles were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and laser diffraction spectroscopy (LDS). The metal wear behavior was studied by means of a Four-Ball tribology test with wear measured. Wear roughness in micro-scale was investigated by high resolution optical microscopy (OM) , 3D rendering optical technique and SEM image processing method. It was found that the ball wear scar diameter increased proportionally to the soot primary particle size. The effect of biodiesel contamination were also increasing in wear scar diameter.
2017-11-05
Technical Paper
2017-32-0104
C.J. Chiang, T.F. Kuo, Weiliem Abubakar, G. Lee, W.R. Huang
The purpose of this thesis is to establish a dynamic an Ultracapacitor model, including equivalent circuit model, a thermal dynamic model and an aging model. Model parameter identification is conducted based on Alternative Current Impedance Spectroscopy (ACIS) experiment and least squares method to obtain the Ultracapacitor equivalent series resistance (ESR), constant phase element magnitude (Adl), electrolyte resistance (Rel) and constant phase element exponent (γ) at various voltages and temperatures. Various mathematical models are applied to describe the aging process of parameters. The Ultracapacitor aging model is then validated against voltage and temperature measurements under various charge/discharge cycles at nature heat dissipation condition. All the experiment results indicated that the Ultracapacitor aging model is capable of predictions the dynamic behaviors of Ultracapacitor after various periods of aging process.
2017-11-05
Technical Paper
2017-32-0038
Rose Mary Simon Palackal, Balagovind Nandakumar Kartha, Karthikeyan Ramachandran, Srikanth Vijaykumar, Pramod Reddemreddy
Today, 99% of the two wheelers in India operate with carburetor based fuel delivery system. But with implementation of Bharath Stage VI emission norms, compliance to emission limits along with monitoring of components in the system that contributes towards tail pipe emissions would be challenging. With the introduction of the OBD II (On-Board Diagnostics) and emission durability, mass migration to electronically controlled fuel delivery system is very much expected. The new emission norms also call for precise metering of the injected fuel and therefore demands extended calibration effort. The calibration of engine management system starts with the generation of pre-calibration dataset capable of operating the engine at all operating points followed by base calibration of the main parameters such as air charge estimation, fuel injection quantity, injection timing and ignition angles relative to the piston position.
2017-11-05
Technical Paper
2017-32-0045
Yoshihito Itou, Daiki Itou, Minoru Iida
Recently the response of the engine speed at starting has more importance than ever for quick start satisfying rider’s needs, as well as exhaust emissions. We have developed a simulation for studying engine and starter specifications, engine control algorithm and other engine control parameters. This system can be utilized to realize appropriate starting time by considering air-fuel ratio under various conditions. This paper addresses what are taken account of in our method. Examples applying this to a conventional motorcycle engine are shown.
2017-11-05
Technical Paper
2017-32-0065
Riccardo Basso, Hans-Jürgen Schacht, Schmidt Stephan, Roland Kirchberger, Matthias Rath, Markus Neumayer, Christian Reisenberger
Small engines for non-automotive and two wheeler applications have a reduced number of sensors. For fulfilling emission regulations a cost effective way is an enhanced use of standard sensors in order to obtain more information from the existing sensors. The delivered information can then be used for an on-board diagnosis. Moreover, it is important to control the quality of the product during engine production; therefore an end-of-line cold engine test is often made. With this measure it is possible to detect faults, wrong tolerances or assembly in order not to deliver faulty engines to the customers. In this paper, an enhanced use of sensors for fault detection will be discussed. It is possible to obtain more information from the signal or to use the sensor for detecting other parameters. For extracting information signal analysis methods will be used with focus on the computational power need since the ECU performance is limited.
2017-11-05
Technical Paper
2017-32-0078
Justus Weßling, Fabian Rauber, Fabian Titus, Kai W. Beck, Tilman Seidel, Stefan Schweiger, Florian Schumann, Tim Gegg
Small gasoline engines are used in motorcycles and handheld machinery, because of their high power density, low cost and compact design. The reduction of hydrocarbon emissions and fuel consumption is an important factor regarding the upcoming emission standards and operational expenses. The scavenging process of the two-stroke engine causes scavenging losses [1]. A reduction in hydrocarbon emissions due to scavenging losses can be achieved through a better understanding of the inner mixture formation. The time frame for fuel vaporization is limited using two-stroke SI engines by the high number of revolutions. With crank angle resolved optical methods it is possible to analyze the mixture formation behavior and combustion. A topic of these investigations is the use of alternative fuels such as alcohol- or butanol-blends and the analysis of their impact on the engine behavior.
2017-11-05
Technical Paper
2017-32-0050
Shuhei Takahata, Takahiro Ishikawa, Takahiro Yamashita, Takuya Izako Hiroki Kudo, Kento Shimizu, Akira Iijima, Hideo Shoji
Internal combustion engines have been required to achieve even higher efficiency in recent years in order to address environmental concerns. However, knock induced by abnormal combustion in spark-ignition engines has impeded efforts to attain higher efficiency. Knock characteristics during abnormal combustion were investigated in this study by in-cylinder visualization and spectroscopic measurements using a four-stroke air-cooled single-cylinder engine. The results revealed that knock intensity and the manner in which the autoignited flame propagated in the end gas differed depending on the engine speed.
2017-11-05
Technical Paper
2017-32-0052
Katsunori Tasaki
Misfire is the condition where the engine does not fire correctly due to an ignition miss or poor combustion of the air fuel mixture, resulting in serious deterioration of tailpipe emissions due to the discharge of unburned gas. In order to prevent further exacerbating environmental problems, misfire detection is obligatory in On Board Diagnosis (OBD) II systems. OBD II technology for passenger cars cannot be easily adopted to motorcycles for several reasons. However, very little research has been reported on misfire detection for an unevenly firing engine in which the degree of contribution to engine output and the variation pattern of angular velocity show a large difference between cylinders, an aspect that is unique to motorcycles. This research focuses on uneven firing V-twin motorcycle engines, to explore misfire detection techniques using variation characters in crank angular velocity.
2017-11-05
Technical Paper
2017-32-0092
S. Di Iorio, A. Irimescu, S.S. Merola, P. Sementa, B. M. Vaglieco
It is well known that ethanol can be used in spark-ignition (SI) engines as a pure fuel or blended with gasoline. High enthalpy of vaporization of alcohols can affect air-fuel mixture formation prior to ignition and may form thicker liquid films around the intake valves, on the cylinder wall and piston crown. These liquid films can result in mixture non-homogeneities inside the combustion chamber and hence strongly influence the cyclic variability of early combustion stages. Starting from these considerations, the paper reports an experimental study of the initial phases of the combustion process in a single cylinder SI engine fueled with commercial gasoline and anhydrous ethanol, as well as their blend (50%vol alcohol). The engine was optically accessible and equipped with the cylinder head of a commercial power unit for two-wheel applications, with the same geometrical specifications (bore, stroke, compression ratio).
2017-10-31
White Paper
WP-0003
Actuators are the key to sophisticated machines that can perform complex tasks previously done by humans.
2017-10-25
White Paper
WP-0002
The environmental impact of hydrocarbon-burning aircraft, both from the perspective of gas emissions and that of noise, is one of the main motivations for the move to electric propulsion. The added benefit from this shift to electric propulsion is that it has resulted in lowering the costs of electrical components such as motors, power electronic (PE) circuits, and batteries that are essential to this technology. This white paper seeks to explore the history, architecture, electrical components, and future trends of electric flight technology.
2017-10-13
Technical Paper
2017-01-7005
Lijuan Wang, Jeffrey Gonder, Eric Wood, Adam Ragatz
Abstract Fuel consumption (FC) has always been an important factor in vehicle cost. With the advent of electronically controlled engines, the controller area network (CAN) broadcasts information about engine and vehicle performance, including fuel use. However, the accuracy of the FC estimates is uncertain. In this study, the researchers first compared CAN-broadcasted FC against physically measured fuel use for three different types of trucks, which revealed the inaccuracies of CAN-broadcast fueling estimates. To match precise gravimetric fuel-scale measurements, polynomial models were developed to correct the CAN-broadcasted FC. Lastly, the robustness testing of the correction models was performed. The training cycles in this section included a variety of drive characteristics, such as high speed, acceleration, idling, and deceleration. The mean relative differences were reduced noticeably.
2017-10-12
White Paper
WP-0005
Annie Chang, Nicolas Saunier, Aliaksei Laureshyn
To date, the universal metric for road safety has been historical crash data, specifically, crash frequency and severity, which are direct measures of safety. However, there are well-recognized shortcomings of the crash-based approach; its greatest drawback being that it is reactive and requires long observational periods. Surrogate measures of safety, which encompass measures of safety that do not rely on crash data, have been proposed as a proactive approach to road safety analysis. This white paper provides an overview of the concept and evolution of surrogate measures of safety, as well as the emerging and future methods and measures. This is followed by the identification of the standards needs in this discipline as well as the scope of SAE’s Surrogate Measures of Safety Committee.
2017-10-08
Technical Paper
2017-01-2376
Nic Van Vuuren, Phil Armitage
Abstract Selective Catalytic Reduction (SCR) diesel exhaust aftertreatment systems are virtually indispensable to meet NOx emissions limits worldwide. These systems generate the NH3 reductant by injecting aqueous urea solution (AUS-32/AdBlue®/DEF) into the exhaust for the SCR NOx reduction reactions. Understanding the AUS-32 injector spray performance is critical to proper optimization of the SCR system. Specifically, better knowledge is required of the formation of near-nozzle deposits that have been observed on existing underfloor SCR systems. The current work presents in-situ time lapse imaging of an underfloor mounted AUS-32 exhaust-mounted urea dosing unit. The operating conditions under examination are representative of low-load low speed urban driving interspersed with high temperature exposures typical of periodic DPF regeneration.
2017-10-08
Technical Paper
2017-01-2367
Ganesan Mahadevan, Sendilvelan Subramanian
Abstract Control of harmful emissions during cold start of the engine has become a challenging task over the years due to the ever increasing stringent emission norms. Positioning the catalytic converter closer to the exhaust manifold is an efficient way of achieving rapid light-off temperature. On the other hand, the resulting higher thermal loading under high-load engine operation may substantially cause thermal degradation and accelerate catalyst ageing. The objective of the present work is to reduce the light-off time of the catalyst and at the same time reduce the thermal degradation and ageing of the catalyst to the minimum possible extent by adopting an approach with Dynamic Catalytic Converter System (DCCS). The emission tests were conducted at the cold start of a 4 cylinder spark ignition engine with DCCS at different positions of the catalyst at no load conditions.
2017-10-08
Technical Paper
2017-01-2403
Yanzhao An, R Vallinayagam, S Vedharaj, Jean-Baptiste Masurier, Alaaeldin Dawood, Mohammad Izadi Najafabadi, Bart Somers, Bengt Johansson
Abstract In-cylinder visualization, combustion stratification, and engine-out particulate matter (PM) emissions were investigated in an optical engine fueled with Haltermann straight-run naphtha fuel and corresponding surrogate fuel. The combustion mode was transited from homogeneous charge compression ignition (HCCI) to conventional compression ignition (CI) via partially premixed combustion (PPC). Single injection strategy with the change of start of injection (SOI) from early to late injections was employed. The high-speed color camera was used to capture the in-cylinder combustion images. The combustion stratification was analyzed based on the natural luminosity of the combustion images. The regulated emission of unburned hydrocarbon (UHC), carbon monoxide (CO) and nitrogen oxides (NOX) were measured to evaluate the combustion efficiency together with the in-cylinder rate of heat release.
2017-10-08
Technical Paper
2017-01-2412
Dojoong Kim, Dong Hyeong Lee, Jong Wung Park, Soo Hyun Hwang, Wan Jae Jeon
Abstract This paper introduces a two-step variable valve actuation (VVA) mechanism equipped with an electronic switching system, which can be applied to OHC valve trains with end pivot rocker arms. The electronic switching system is driven by a dedicated solenoid and is not affected by the temperature or pressure of the engine oil. Therefore, not only can the dynamic stability be secured at the time of mode switching but the operation delay time can also be kept short enough. Several models of two-step VVA mechanisms were fabricated and the operability of the mechanism and switching system was experimentally confirmed. The two-step VVA mechanism developed in this study can also be used as a cylinder deactivation (CDA) system by assigning the lift of the low-speed cam to be zero. By attaching a roller to the portion of the rocker arm that is in contact with the base cam, the problem of pad wear, which is often present in CDA mechanism, is also fundamentally solved.
2017-10-08
Technical Paper
2017-01-2425
Ramit Verma, Ramdas R Ugale
Abstract On two wheelers, magneto/alternator generates either single/three phase AC power and Regulator Rectifier Unit (RRU) does regulated rectification to charge the battery. In order to face the requirements of 2-wheeler engine with respect to upcoming stringent regulations like electronic fuel injection (EFI), anti-lock braking system (ABS), automatic headlamp on (AHO) in emerging markets like India; vehicles demand more electrical power from batteries. This demands higher power from alternator and consequently from RRU. Requirement of higher output power presents challenges on regulator rectifier unit in terms of size, power dissipation management and reliability. In this paper, improved performance of MOSFET based RRU is discussed in comparison to Silicon Controlled Rectifier (SCR) based RRU. The motivation/benefits of MOSFET based design is described along with the thermal behavior and temperature coefficient performance of RRU with test results.
2017-10-08
Technical Paper
2017-01-2453
Shuang Liu, Lina Pan, Xin Jiang, Yujiao Wang, Kun Liu, Yang Xia
Abstract Quick drop battery system was the core components of the electric vehicles, the reliability and compatibility of quick drop battery system was directly related to the popularization and application of electric vehicles. In this article, a split type battery management system and a split type high voltage architecture was used to achieve better charging compatibility. Meanwhile the number of fast switching connector’s pin is reduced and the plug life was prolonged to more than 10000 times by using floating structure. For battery management system (BMS), the state of charge (SOC) estimation was based on dynamic voltage correction, and make estimation accuracy reach to less than 5%. Rotary slot limit and fast locking mechanism had been designed for the first time and the precision of battery system assembling could control within 3mm, hence the floating structure’s damage could be reduced and the mechanical life could be enhanced.
2017-10-08
Technical Paper
2017-01-2454
Yiqi Jia, Gangfeng Tan, Cenyi Liu, Shengguang Xiong, Zehao Yang, Xingmang Zheng
Abstract In these years, the advantages of using phase change material (PCM) in the thermal management of electric power battery has been wide spread. Because of the thermal conductivity of most phase change material (eg.wax) is low, many researchers choose to add high conductivity materials (such as black lead). However, the solid-liquid change material has large mass, poor flow-ability and corrosively. Therefore, it still stays on experiential stage. In this paper, the Thermal characteristics of power battery firstly be invested and the requirements of thermal management system also be discussed. Then a new PCM thermal management has been designed which uses pure water as liquid phase change material, adopts PCM with a reflux device for thermal management.
2017-10-08
Technical Paper
2017-01-2452
Kingsley Joel Berry, Abdrahamane Traore, Aravind Krishna, Pavankumar Gangadhar, Allan Taylor
This paper documents the electrical infrastructure design of a Hybrid Go Kart competition vehicle which includes a dual Fuel Cell power system, Ultra Capacitors for energy storage, and a dual AC induction motor capable of independent drive. The Kart was built primarily to compete in the 2009 Formula Zero international event. This paper emphasized the vehicle model and control strategy as a result of three (3) graduate student research projects. The vehicle was fabricated and tested but did not participate in the race competition since the race organization folded. The vehicle model was developed in Simulink to determine whether the fuel cell and ultra-capacitor combination will be sufficient for peak transient power requirement of 14 kW. The vehicle’s functional description and performance specifications are documented including the integration of the fuel cell power modules, energy storage system, power converters, and AC motor and motor controllers.
2017-10-08
Journal Article
2017-01-2459
Liu Xiaojun, Yu Jinpeng, Yang Xia, Wu Daoming, Jie Zhu
Abstract In the case of electric vehicles, due to the charging current limitation of lithium battery at low temperatures (below -20°C), it has been proposed to heat the battery pack up to a suitable temperature range before charging through a liquid-heating plate with PTC. However, at a low state of charge (SOC), there is a question which one could take the place of battery pack to supply power for PTC when heating. So that off-board charger (OFC) has been considered to supply power for PTC in this paper. In order to control the current charging into the battery pack as less as possible at low temperatures, three control schemes of battery management system (BMS) are proposed and compared. Scheme 1: BMS controls the value of charging current request close to the working current of PTC. Scheme 2: BMS controls the value of charging voltage request to reach a state of relative balance. Scheme 3: BMS disconnects the pack from the charger and keeps the connection between PTC and charger.
2017-10-08
Technical Paper
2017-01-2198
Zhihong Li, Guoxiu Li, Lan Wang, Hongmeng Li, Jie Wang, Haizhou Guo, Shuangyi He
Abstract The electromagnetic valve driving mechanism is the significant equipment, which plays a vital role in the unit pump injection system; therefore, the performance of the electromagnetic valve directly influences the function of the control system. Based on the operation conditions of the unit pump injection system, a steady electromagnetic valve model was modified to study the influence factors of electromagnetic force and the best combination to get the maximum electromagnetic force. The validation model was verified by experiment. The effects of some crucial parameters upon the electromagnetic force were investigated in the present paper, (including working airspace, magnetic pole’s cross-sectional area, coil position, coil turn, the armature thickness). The results show that the electromagnetic force of the solenoid valve enhanced with the increase of driving current and with the decrease of working airspace.
Viewing 1 to 30 of 16574