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Viewing 31 to 60 of 110718
2017-11-05
Technical Paper
2017-32-0008
Pei Yi Lim, Youhei Inagaki
Sustainability trends and reduced fuel consumption as a value proposition to end users have led to an ever-increasing focus on fuel efficiency in the personal mobility segment. This is evident in the development of smaller and lighter engine hardware with optimized combustion systems as well as the lowering of engine oil viscosity grades and formulation of additives with improved friction properties. Due to the unique challenges of lubricating motorcycle engines, the development of fuel efficient motorcycle engine oil presents several technical dilemmas. The reduction of oil viscosity gives rise to durability concerns particularly in such high temperature and high speed operating conditions, while the formulation of additives with lower friction properties may affect clutch friction that is necessary for a manual motorcycle.
2017-11-05
Technical Paper
2017-32-0030
Yoshihide Ota, Hiroshi Enomoto, Jun Higashihara, Masahiro Sasao, Noboru Hieda, Yoshikazu Teraoka
In internal combustion engine, it is necessary to grasp droplet evaporation for using liquid fuel efficiency and improving exhaust gas composition. However, it has not known completely yet. In this study, fuel droplet of approximately 20μm diameter that is assumed to be in combustion chamber is injected by experimental apparatus. After that, droplet goes to butane flame. We observed by high-speed camera, and experimentally considered the effects of heat flux on the fuel droplet evaporation and breakup phenomenon. For the sample fuel, we use kerosene and diesel oil. It is important for understanding evaporation condition to know temperature around droplet in butane flame. Thus, flame temperature is measured by sheathed thermocouple. Heat flux is changed by initial velocity. From experiment, we found some result. Time that from injector tube to location of breakup of the droplet is short by increasing heat flux.
2017-11-05
Technical Paper
2017-32-0032
Rizal Mahmud, Seong Bum Kim, Toru Kurisu, Keiya Nishida, Yoichi Ogata, Jun Kanzaki, Tadashi Tadokoro
Heat loss is more critical for the thermal efficiency improvement in small size diesel engines than large-size diesel engines. More than half of total heat energy in the internal-combustion engine is lost by cooling through the cylinder walls to the atmosphere and the exhaust gas. Therefore, the new combustion concept is needed to reduce losses in the cylinder wall. In a Direct Injection (DI) diesel engine, the spray behavior, including spray-wall impingement has an important role in the combustion development to reduce heat loss. The aim of this study is to understand the mechanism of the heat transfer from the spray and flame to the impinging wall. Experiments were performed in a constant volume vessel (CVV) at high pressures and high temperatures. Fuel was injected using a single-hole injector with a 0.133 mm diameter nozzle. Under these conditions, spray evaporates, then burns near the wall. Spray/flame behavior was investigated with a high-speed video camera.
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
2017-32-0041
Johannes Hiesmayr, Stephan Schmidt, Stefan Hausberger, Roland Kirchberger, Christian Zinner, Patrick Filips, Roland Wanker, Hubert Friedl
Real world operating scenarios have a major influence on emissions and fuel consumption. To reduce climate-relevant and environmentally harmful gaseous emissions and the exploitation of fossil resources, deep understanding concerning the real drive behavior of mobile sources is needed because emissions and fuel consumption of e.g. passenger cars, operated in real world conditions, considerably differ from the officially published values which are valid for specific test cycles only [1]. Due to legislative regulations by the European Commission a methodology to measure real drive emissions RDE is well approved for heavy duty vehicles and automotive applications but may not be adapted similar to two-wheeler-applications. This is due to several issues when using the state of the art portable emission measurement system PEMS that will be discussed.
2017-11-05
Technical Paper
2017-32-0042
Johannes Hiesmayr, Stephan Schmidt, Stefan Hausberger, Roland Kirchberger, Christian Zinner, Patrick Filips, Roland Wanker, Hubert Friedl
The reduction of environmentally harmful gases and the ambitions to reduce the exploitation of fossil resources lead to stricter legislation for all mobile sources. Legislative development significantly affected improvements in emissions and fuel consumptions over the last years, mainly measured under laboratory conditions. But real world operating scenarios have a major influence on emissions and it is already well known that these values considerably differ from officially published figures [1]. There are regulated emissions by the European Commission by means of real driving scenarios for passenger cars. A methodology to measure real drive emissions RDE is therefore well approved for automotive applications but was not adapted for two-wheeler-applications yet [2]. Hence measurements have been performed on-road and on chassis dynamometer for motorcycles with the state of the art RDE measurement equipment to be prepared for possible future legislation.
2017-11-05
Technical Paper
2017-32-0046
Tomoyuki Mukayama, Ryota Nishigami, Annisa Bhikuning, Go Asai, Masaki Kuribayashi, Eriko Matsumura, Jiro Senda
The CO2 gas dissolved fuel for the diesel combustion is effective to reduce the NOx emissions to achieve the internal EGR (Exhaust Gas Recirculation) effect by fuel. This method has supplied EGR gas to the fuel side instead of supply EGR gas to the intake gas side. The fuel has followed specific characteristics for the diesel combustion. When the fuel is injected into the chamber in low pressure, this CO2 gas is separated from the fuel spray. The distribution characteristics of the spray are improved and the improvement of the thermal efficiency by reduction heat loss in the combustion chamber wall, and reduce soot emissions by the lean combustion is expected. Furthermore, this CO2 gas decreases the flame temperature. Further, it is anticipated to reduce NOx emissions by the spray internal EGR effect.
2017-11-05
Technical Paper
2017-32-0048
Tomoaki Yatsufusa, Kentaro Takatani, Keigo Kii, Shinsuke Miyata
Multiple ion-probes method provides fine measurement on propagating flame by using multiple ion-probes installed tow-dimensionally on the wall surface of confined chamber. Each ion-probe detects the arrival of propagating flame and the detecting time is recorded. The data set of flame detecting times is able to re-generate the temporary and spatially detailed behavior of flame propagation. Because ion-probe itself generally has physical and thermal strength, multiple ion-probe method is suitable method for detailed measurement of the combustion resulting pulsatile high pressure such as in reciprocating piston engines. In the present study, flame measurement technic by multiple ion-probes has been experimentally introduced for measuring the combustion in 2-stroke gasoline engine. The present paper reports the detailed results of measurement on propagating flame in the engine. In addition, newly clarified technical issues of this technic is also mentioned.
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
2017-32-0049
Kohei Hirano, Yuki Chihara
The new titanium fuel tank has been developed to reduce weight of the fuel tank of production motocrossers. While the titanium permits deep drawing to shape a tank by presswork, the processing of titanium material is difficult, hence no past application of the material for a motorcycle fuel tank. This project was aimed at development of new techniques for mass production of titanium fuel tanks, and succeeded in mass production of titanium fuel tanks having an adequate durability to apply to a motocrosser that can receive a strong impact while driving. As a result, approximately 40% of weight reduction from the plastic fuel tank having the same fuel capacity was realized.
2017-11-05
Technical Paper
2017-32-0053
Alexander Winkler, Gernot Grabmair
In this study we focus on systematic disturbances caused by the motorcycle pitch dynamic when measuring longitudinal acceleration on motorcycles using low-cost acceleration sensors. Major systematic influences in the sensor measurement like gravitational acceleration, suspension dynamics and the road slope are addressed. During acceleration phases the motorcycle pitch angle changes according to the suspension setting. As a result the longitudinal sensing axis of the accelerometer includes parts of the gravitational acceleration and lags parts of the longitudinal acceleration. Gravitational acceleration has also significant influence on inclined roads. To obtain correct values of the effective longitudinal acceleration, the disturbances in the measured signal are analyzed and in further consequence compensated. For this purpose a linearized in-plane-dynamics model of the motorcycle is derived from a comprehensive multibody simulation.
2017-11-05
Technical Paper
2017-32-0055
Yota Sakurai, Yoshinori Nakao, Astushi Hisano, Masahito Saitou, Kunihiro Tanaka
In this study on the motorcycle engine, we investigated the geometry of the newly developed intake port with an objective of improving the fuel consumption and the torque in practical range. Herein we present the results obtained. We believe that an effective measure for achieving the stated objective is to improve the combustion speed and combustion stability. To realize that, it is necessary to increase the turbulence during combustion and improve the homogeneity of air-fuel mixture. To investigate the feasible shape of the port, the CFD simulation (including fuel spray analysis) was performed and a geometry that improved the turbulent kinetic energy and mixture homogeneity at the time of ignition was selected. For confirming the combustion improvement effect achieved by tumble strengthening, an engine test was conducted with the same amount of intake air as that used in.
2017-11-05
Technical Paper
2017-32-0054
Iman Kartolaksono Reksowardojo, Phonethip Trichanh, Kevin Ferdyamin, Mega Zulfikar Akbar
This research aims to investigate the effect of ethanol blends with pure gasoline to the rate of fuel consumption and emissions of fuel injection motorcycle 115 cc with automatic transmission which is the population is dominant in Indonesia. Variations of the bioethanol mixture are 0%, 5%, 10%, and 20% ethanol. The experiment conducted in two different conditions by using three ways catalytic converter (TWC) in the exhaust pipe and without using TWC in the exhaust pipe. First, all engine setting was originally manufacture setting. Second, the AFR is set in stoichiometry condition (λ = 1) and ignition timing set in MBT timing using modified ECU. The experiment performed on the chassis dynamometer and referred on the standard cycle ECE 15. The results of this experiment showed that increment of ethanol content in the fuel makes the rate of fuel consumption and CO2 emission both increased but CO and HC emissions decreased.
2017-11-05
Technical Paper
2017-32-0056
Hirotoshi Inui, Toru Sakurai, Eiichi Sato, Tadashi Minoda, Yasuhiro Nakai
Tapered handlebars using high strength aluminum alloys have been applied mainly to motorcycle models requiring weight reduction and high texture appearance that aluminum handlebars can offer as their characteristics. This handle bar is manufactured through extrusion processing. Conventionally used alloys had low extrusion productivity, which led to increased cost of the handlebars. In view of this, we selected an alloy securing the strength by adding a large amount of zinc while reducing the amount of the copper, which deteriorates the extrusion productivity, to the minimum adding amount, in consideration of maintaining the stress corrosion cracking resistance. However, a large amount of zinc decreases the stress corrosion cracking resistance. Therefore, in order to obtain a metallic structure favorable to the prevention of stress corrosion cracking, the mandrel extrusion was applied for the pipe manufacturing method, and heat treatment condition and swaging condition were optimized.
2017-11-05
Technical Paper
2017-32-0060
Hiroto Takahashi, Toshiki Shinohara
Many general purpose engines, such as the ones used in construction machines, operate in environments with excessive amounts of airborne dust, and are thereby equipped with a cyclone air cleaner so that they can remove as much dust from contaminated air streams in the engine. However, the compact general purpose engine is mainly a single-cylinder type, and the intake flow pulsates. Since the centrifugal action of the cyclone air cleaner under the intake pulsation changes according to the pulsation, it is difficult to enhance the dust separation performance. In this study, we aimed to determine a cyclone air cleaner factor with high purification performance even under the intake pulsation conditions of a general purpose engine. We have designed an ideal geometry for the cyclone air cleaner, which centrifugally separates dust during inhaling and discharges the centrifuged dust using positive pressure due to pulsation.
2017-11-05
Technical Paper
2017-32-0059
Yoshinori Nakao, Atsushi Hisano, Masahito Saitou, Kozo Suzuki, Katsumi Sobakiri
In this paper, it is also elucidated that the influence of the downstream injection, which caused different fuel behavior in contrast with upstream injection, on the THC after warm-up and at the maximum power, as well as its mechanism. The mechanism is clarified by use of the intake port visualization system. First, at each injection position, the effect of injection timing on THC emission after warm-up was evaluated. In the downstream injection, THC emission increases during the injection timing, in which the fuel spray directly flows in-cylinder during the intake process (hereinafter defined as the intake valve opening injection timing), and the amount of THC emission is reduced at the other injection timing (hereinafter defined as the intake valve closing injection timing). Based on the results of visualizing the intake port, injected fuel phase near the intake valve is spray in the downstream injection.
2017-11-05
Technical Paper
2017-32-0061
Shogo Watanabe, Tatsuya Kuboyama, Yasuo Moriyoshi, Kei Yoshimura
It has been widely known that thermal and fuel stratifications of in-cylinder mixture are effective to reduce in-cylinder pressure rise rate during high load HCCI operations. In order to optimize a combustion chamber design and combustion control strategy for HCCI engines with wide operational range, it is important to know quantitatively the influence of the temperature and fuel concentration distributions on ignition and heat release characteristics. At the same time, it is important to know the influence of in-cylinder flow and turbulence on the temperature and fuel concentration distributions. In this study, a numerical simulation of HCCI combustion were conducted to investigate the effects of the in-cylinder flow and turbulence, and the distributions of temperature on ignition and combustion characteristics in HCCI combustion.
2017-11-05
Technical Paper
2017-32-0067
Ranjana Meena, Pradeep Ramachandra, Adwitiya Dube
With the increased demand of mobility in the form of two-wheelers and the continued dominant share of Internal Combustion Engines (ICE) in Indian market, there is considerable influence on the deterioration of air quality. The regulators in this region have legislated Bharat Stage 6 (BS6) as a measure to restrict tail pipe emissions, which necessitates the automotive industry to work towards emission optimization measures. Some of the factors influencing this includes, air-fuel mixture formation, spray targeting, fuel properties, flow dynamics, combustion chemical kinetics, exhaust after-treatment etc. The focus area of this paper is to study the influence of air-fuel mixture formation which is highly dependent on fuel droplet atomization, injection timing, fuel injector, injection pressure and mixture preparation techniques to reduce the engine out emissions.
2017-11-05
Technical Paper
2017-32-0066
Jüri Lavrentjev, Hans Rämmal
To control noise emission from internal combustion inlet, designers often choose small chamber type silencers at the inlet. In order to improve the inlet acoustic efficiency, inlet ducts with improved acoustic attenuation can be used. One potentially applicable material is acoustic metamaterial rapidly gaining popularity in different fields of engineering application. Small engine inlet duct, designed by using acoustic metamaterial structure comprising an array of resonators inside the wall of a rigid duct is investigated in this study. Experimental investigation of different designs is performed to characterize the acoustic behavior in terms of transmission loss (TL). By connecting multiple resonators of different size and location it is shown that a broadband TL can be achieved. The resulted attenuation band can be tuned by varying the resonator physical characteristics, showing promising potentials such of the material in the described application.
2017-11-05
Technical Paper
2017-32-0071
Jürgen Tromayer, Michael Gaber, Roland Kirchberger, Fern Thomassy, Scott McBroom
Abstract Meeting upcoming emission limits such as EURO 5 with comparatively simple and low-cost vehicles will be very challenging. On the engine side, a big effort in terms of fuelling, combustion optimization as well as exhaust gas aftertreatment will be necessary without any doubt. Besides that, additional system optimization potential can be gained by a systematic adaptation of the drive train. One approach is to use a CVT (Continuously Variable Transmission) system to run engines in specific ranges with good fuel economy. However, existing belt driven CVTs show comparatively poor efficiencies. To overcome this drawback, the integration of a novel Continuously Variable Planetary Transmission (CVP), designed and developed by Fallbrook Technologies, was investigated in detail. For this purpose, a longitudinal dynamics simulation in Matlab-Simulink was carried out to compare a standard mass production vehicle drive train with several CVP setups.
2017-11-05
Technical Paper
2017-32-0068
Yoshihiro Aramaki, Shunsuke Ishimitsu, Kenta Murai, Kazuki Yoshida, Toshihisa Takaki, Takanori Chino, Kenta Suzuki
The number of people experiencing psychological discomfort due to the increasing amount of noise emanating from motor vehicles has been on the rise. Legal regulations define the permissible level of vehicle noise in a given area. Active noise control (ANC) is a noise cancellation method that reduces low-frequency sounds, such as engine noise, effectively. Furthermore, this method is suitable for controlling engine noise because the equipment necessary to perform it is small and does not require a large space for installation. Advances in digital processing technology have increased the scope of ANC’s applications, and it is no longer restricted to use in motor vehicles. The purpose of this study is to demonstrate the effectiveness of the proposed method in reducing the motor vehicle engine noise produced during acceleration. In this study, we attempt to control the engine sounds from a vehicle with a four-cylinder four-stroke engine.
2017-11-05
Technical Paper
2017-32-0076
Adyati Yudison, Driejana, Iman K. Reksowardojo, Aminudin Sulaeman
Motorcycles account for almost 80% of private vehicles in Indonesia, with an annual growth rate of 12% per year. This paper aims to investigate the emission profiles of CO2, CO, HC and NOx based on typical fuel and motorcycle types in Indonesia. Questionnaire surveys were undertaken to gather fuel type, engine technology and capacity representing the motorcycle population in Bandung City, Indonesia. Emissions were measured based on six-speed variations on a chassis dynamometer. Questionnaire surveys from 290 respondent show that EURO II and EURO III technology with engine capacity less than 150cc is the most utilized type of motorcycle in Bandung. Most of the users’ chose RON 90 and RON 92 gasoline. Based on the results, four groups of 5 motorcycle of EUROII-RON90, EUROII-RON92, EUROIII-RON90, and EUROIII-RON92 were tested. Emission data showed that the higher the speed, the lower the emission, except for CO and NOx which have a different pattern.
2017-11-05
Technical Paper
2017-32-0077
Herman Saputro, Laila fitriana, Masato Mikami
Experiments of flame-spread of fuel droplets have been performed in microgravity actively. However, the experiment has limitation in the number of droplets due to relatively short microgravity durations in the ground based facilities. It is difficult to conduct flame spread experiments of large scale droplet clouds in microgravity. This study conducted simulation of flame-spread behavior in randomly distributed large-scale droplet clouds by using a percolation approach, in order to make a theoretical link the gap between droplet combustion experiments and spray combustion phenomenon with considering two-droplet interaction. Droplets are arranged at lattice points in 2D lattice. The occurrence probability of group combustion (OPGC) is calculated as a function of the mean droplet spacing (S/d0)m.
2017-11-05
Technical Paper
2017-32-0073
Jörn Judith, Denis Neher, Maurice Kettner, Markus Klaissle, Darko Kozarac
Homogeneous charge compression ignition (HCCI) in natural gas fueled engines is thought to achieve high efficiency and low NOx emissions. While automotive applications require various load and speed regions, the operation range of stationary cogeneration engines is narrower. Hence, HCCI operation is easier to reach and more applicable to comply with future emission standards. This study presents computationally investigations of the auto-ignition ranges of a stationary natural gas HCCI engine. Starting from a detailed 1D engine cycle simulation model, a reduced engine model was developed and coupled to chemical kinetics using AVL Boost. Compression ratio, air-fuel ratio, internal EGR rate (iEGR) and intake temperature were varied for three different speeds, namely 1200, 1700 and 2200 rpm. Each examination includes a full factorial design study of 375 configurations. In the first step, the combustion was calculated using the GRI-mechanism 3.0 and a single zone combustion model.
2017-11-05
Technical Paper
2017-32-0083
Makoto Hasegawa, Takanobu Kaneko
ISO 26262, an international functional safety standard of electrical and/or electronic systems (E/E systems) for motor vehicles, was published in November 2011 and it is expected that the scope will be extended to motorcycles in a second edition of ISO 26262 going to be published in 2018. ISO/DIS 26262 second edition published in 2016 has Part 12 as a new part in order to apply ISO 26262 to motorcycle. Proper estimation of Exposure, Controllability, and Severity in accordance with ISO/DIS 26262 Part 12, are key factors to determine Motorcycle Safety Integrity Level. To estimate precise these factors, there would be a case that it might not be appropriate to apply studies done for passenger car to motorcycle, and it would be necessary to apply motorcycle specific knowledge and estimation methods. In our previous studies we clarified these motorcycle specific issues and studied the method for the adaptation.
2017-11-05
Technical Paper
2017-32-0079
Tsukasa Shimizu, Jin Itou, Hideki Shirazawa, Yasuyuki Muramatsu
It is important to make small and light weight motor for small EV. It is necessary to select appropriate cooling system (liquid cool or air cool) according to motor output. We thought that there is a threshold output that makes the volume smaller and the weight lighter including the liquid cooling system. As a result of the rough calculation, it was found that the weight can be reduced by adopting the liquid cooling for at about 10kW or more. In this study we focused on motor and cooling system volume and weight and tried to clarify appropriate cooling system according to motor output.
2017-11-05
Technical Paper
2017-32-0086
Shinji Takayanagi, Kiyotaka Sakai, Takashi Iwasa, Tomoyuki Matsumura, Shigehiro Yamaguchi, Kenji Tanaka
A low fuel consumption tire with an affordable price that is applicable for small motorcycles marketed mainly for India and Southeast Asian countries was developed. Two contradicting requirements, which are reduction of the rolling resistance and retention of the wet grip performance, were satisfied by applying a method based on viscoelastic properties of the tread rubber. Regarding the composition of compound of the tread rubber, the amounts of carbon black and oil were reduced instead of using silica. In addition, a polymer having a high glass transition temperature was employed. Moreover, response to the roll motion, which is unique in motorcycles, was made satisfactory to the requirement by modifying the dynamic modulus E* of the tread rubber. With those measures, the rolling resistance was reduced by more than 15% to conventional tires while maintaining the basic performances such as tire grip and stability in maneuvering.
2017-11-05
Technical Paper
2017-32-0087
Sangriyadi Setio, Wiranto Arismunandar, Rudy Ong, Adefrid Dwithama, Stefanus Adrian, Angela Claudia, Nu’man Amri Maliky, Jery Octavianus, Muhammad Alif Mabbrur, Michell Tjhoi
Developing and designing fuel efficient vehicle for a one gallon of fuel marathon is a challenging task. Engines have to be optimized to achieve maximum fuel efficiency. In this study, we evaluate the optimal compression ratio (CR) and ignition timing that produce the best torque in a custom gasoline-based-motorcycle-engine that use ethanol E100 fuel. In the first experiment, CR was adjusted between 9 and 12 to evaluate its effect on the engine mileage’s record. The experiment was conducted on the test track. In the second experiment, Ignition timing was adjusted by a custom-made engine control unit (ECU) between 15° and 45° before top dead center (BTDC). The engine performance was investigated in terms of best torque and brake specific fuel consumption (BSFC), with variation of engine speed between 1500 and 8000. The test was conducted on dynamometer. The test was also performed in constant compression ratio and stoichiometric air-fuel ratio, 9.
2017-11-05
Technical Paper
2017-32-0084
Hyota Hoshino, Tatsuya Sato, Shuntaro Takano, Yuya Motoki, Hiroto Tanaka, Yuya Higuchi, Akira Iijima, Tomohiko Asai, Mitsuaki Tanabe, Yoshito Ashizawa, Junichi Sekiguchi, Hideo Shoji
This study focused on a non-equilibrium plasma discharge as a means of assisting HCCI combustion.Experiments were conducted with a four-stroke single-cylinder engine fitted with a spark electrode in the top of the combustion chamber for continuously generating non-equilibrium plasma from the intake stroke to the exhaust stroke. The results showed that applying non-equilibrium plasma to the HCCI test engine advanced the main combustion period that otherwise tended to be delayed as the engine speed was increased. In addition, it was found that the combined use of exhaust gas recirculation and non-equilibrium plasma prevented a transition to partial combustion while suppressing cylinder pressure oscillations at high loads.
2017-11-05
Technical Paper
2017-32-0085
Masaaki Togawa, Takeshi Nishiyama, Keito Agui, Yuki Takamura, Akira Iijima, Hideo SHOJI
This study investigated the effects of recirculated exhaust gas (EGR) and its principal components of N2, CO2 and H2O on moderating Homogeneous Charge Compression Ignition (HCCI) combustion. Experiments were conducted using two types of gaseous fuel blends of DME/propane and DME/methane as the test fuels. The addition rates of EGR, N2, CO2 and H2O were varied and the effects of each condition on HCCI combustion of propane and methane were investigated. The results revealed that the addition of CO2 and H2O had the effect of substantially delaying and moderating rapid combustion. The addition of N2 showed only a slight delaying and moderating effect. The addition of EGR had the effect of optimally delaying the combustion timing, while either maintaining or increasing the indicated mean effective pressure and indicated thermal efficiency ηi.
Viewing 31 to 60 of 110718