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Viewing 241 to 270 of 22839
2015-04-14
Journal Article
2015-01-1690
Cristina Arnal, Yolanda Bravo, Carmen Larrosa, Valentina Gargiulo, Michela Alfè, Anna Ciajolo, María Ujué Alzueta, Ángela Millera, Rafael Bilbao
Abstract Soot fouling on exhaust gas recirculation coolers (EGRc) decreases thermal efficiency, implying the unfulfillment of NOx standards, and increases the pressure drop producing the malfunctioning of this device. The characterization of soot is of great interest since soot physico-chemical properties may have a direct influence on the degree of malfunctioning of EGRc. Thus, the combined analysis and interpretation of all the soot physico-chemical features are essential to correctly interpret its behavior when soot is deposited on the EGRc walls. In this context, the aim of this study is the characterization of five different types of diesel soot which were collected from several high pressure EGRc, working at different conditions (engine bench and vehicle). Each soot sample was characterized by means of elemental analysis, specific surface area (BET method), FESEM, FTIR, TGA, GC-MS and UV-visible spectroscopy.
2015-04-14
Journal Article
2015-01-1746
Hassan Karaky, Gilles Mauviot, Xavier Tauzia, Alain Maiboom
Abstract Reducing NOx tailpipe emissions is one of the major challenges when developing automotive Diesel engines which must simultaneously face stricter emission norms and reduce their fuel consumption/CO2 emission. In fact, the engine control system has to manage at the same time the multiple advanced combustion technologies such as high EGR rates, new injection strategies, complex after-treatment devices and sophisticated turbocharging systems implemented in recent diesel engines. In order to limit both the cost and duration of engine control system development, a virtual engine simulator has been developed in the last few years. The platform of this simulator is based on a 0D/1D approach, chosen for its low computational time. The existing simulation tools lead to satisfactory results concerning the combustion phase as well as the air supply system. In this context, the current paper describes the development of a new NOx emission model which is coupled with the combustion model.
2015-04-14
Journal Article
2015-01-0810
Hao-ye Liu, Zhi Wang, Jian-Xin Wang
Abstract Wide Distillation Fuel (WDF) refers to the fuels with a distillation range from Initial Boiling Point (IBP) of gasoline to Final Boiling Point (FBP) of diesel. Polyoxymethylene Dimethyl Ethers (PODEn) have high oxygen content and cetane number, are promising green additive to diesel fuel. In this paper, WDF was prepared by blending diesel and gasoline at ratio of 1:1, by volume; the mass distribution of oligomers in the PODE3-4 product was 88.9% of PODE3 and 8.46% of PODE4. Diesel fuel (Diesel), WDF (G50D50) and WDF (80%)-PODE3-4 (20%) (G40D40P20) were tested in a light-duty single-cylinder diesel engine, combustion characteristic, fuel consumption and exhaust emissions were measured. The results showed that: at idling condition, G40D40P20 has better combustion stability, higher heat release rate, higher thermal efficiency compared with G50D50.
2015-04-14
Journal Article
2015-01-0809
Joonsik Hwang, Yongjin Jung, Choongsik Bae
Abstract The effect of biodiesel produced from waste cooking oil (WCO) on the soot particles in a compression ignition engine was investigated and compared with conventional diesel fuel. The indicated mean effective pressure of approximately 0.65 MPa was tested under an engine speed of 1200 revolutions per minute. The fuels were injected at an injection timing of −5 crank angle degree after top dead center with injection pressures of 80 MPa. Detailed characteristics of particulate matters were analyzed in terms of transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and elemental analysis. Soot aggregates were collected on TEM grid by thermophoretic sampling device installed in the exhaust pipe of the engine. High-resolution TEM images revealed that the WCO biodiesel soot was composed of smaller primary particle than diesel soot. The mean primary particle diameter was measured as 19.9 nm for WCO biodiesel and 23.7 nm for diesel, respectively.
2015-04-14
Journal Article
2015-01-0902
Koichi Ashida, Hirofumi Maeda, Takashi Araki, Maki Hoshino, Koji Hiraya, Takao Izumi, Masayuki Yasuoka
Abstract To improve the fuel economy via high EGR, combustion stability is enhanced through the addition of hydrogen, with its high flame-speed in air-fuel mixture. So, in order to realize on-board hydrogen production we developed a fuel reformer which produces hydrogen rich gas. One of the main issues of the reformer engine is the effects of reformate gas components on combustion performance. To clarify the effect of reformate gas contents on combustion stability, chemical kinetic simulations and single-cylinder engine test, in which hydrogen, CO, methane and simulated gas were added to intake air, were executed. And it is confirmed that hydrogen additive rate is dominant on high EGR combustion. The other issue to realize the fuel reformer was the catalyst deterioration. Catalyst reforming and exposure test were carried out to understand the influence of actual exhaust gas on the catalyst performance.
2015-04-14
Journal Article
2015-01-0890
Barbara Graziano, Florian Kremer, Stefan Pischinger, Karl Alexander Heufer, Hans Rohs
Abstract The current and future restrictions on pollutant emissions from internal combustion engines require a holistic investigation of the abilities of alternative fuels to optimize the combustion process and ensure cleaner combustion. In this regard, the Tailor-made Fuels from Biomass (TMFB) Cluster at Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University aims at designing production processes for biofuels as well as fuels optimal for use in internal combustion engines. The TMFB Cluster's scientific approach considers the molecular structure of the fuels as an additional degree of freedom for the optimization of both the production pathways and the combustion process of such novel biofuels. Thus, the model-based specification of target parameters is of the utmost importance to improve engine combustion performance and to send feedback information to the biofuel production process.
2015-04-14
Journal Article
2015-01-0892
Alastair Smith, Rod Williams
Abstract The formation of deposits within injector nozzle holes of common-rail injection fuel systems fitted to modern diesel cars can reduce and disrupt the flow of fuel into the combustion chamber. This disruption in fuel flow results in reduced or less efficient combustion and lower power output. Hence there is sustained interest across the automotive industry in studying these deposits, with the ultimate aim of controlling them. In this study, we describe the use of Scanning Electron Microscopy (SEM) imaging to characterise fuel injector hole deposits at intervals throughout an adaptation of the CEC Direct Injection Common Rail Diesel Engine Nozzle Coking Test, CEC F-98-08 (DW10B test)[1]. In addition, a similar adaptation of a previously published Shell vehicle test method [2] was employed to analyse fuel injector hole deposits from a fleet of Euro 5 vehicles.
2015-04-14
Journal Article
2015-01-0957
George Karavalakis, Daniel Short, Diep Vu, Robert Russell, Akua Asa-Awuku, Thomas Durbin
Abstract Biofuels, such as ethanol and butanol, have been the subject of significant political and scientific attention, owing to concerns about climate change, global energy security, and the decline of world oil resources that is aggravated by the continuous increase in the demand for fossil fuels. This study evaluated the potential emissions impacts of different alcohol blends on a fleet of modern gasoline vehicles. Testing was conducted on a fleet of nine vehicles with different combinations of ten fuel blends over the Federal Test Procedure and Unified Cycle. The vehicles ranged in model year from 2007-2014 and included four vehicles with port fuel injection (PFI) fueling and five vehicles with direct injection (DI) fueling.
2015-04-14
Journal Article
2015-01-1004
Joseph R. Theis, Jeong Kim, Giovanni Cavataio
Abstract A laboratory study was performed to assess the potential capability of passive TWC+SCR systems to satisfy the Tier 2, Bin 2 emission standards for lean-burn gasoline applications. In this system, the TWC generates the NH3 for the SCR catalyst from the feedgas NOx during rich operation. Therefore, this approach benefits from high feedgas NOx during rich operation to generate high levels of NH3 quickly and low feedgas NOx during lean operation for a low rate of NH3 consumption. It was assumed that the exhaust system needed to include a close-coupled (CC) TWC, an underbody (U/B) TWC, and an U/B SCR converter to satisfy the emission standards during the FTP and US06 tests while allowing lean operation for improved fuel economy during select driving conditions. Target levels for HC, CO, and NOx during lean/rich cycling were established.
2015-04-14
Journal Article
2015-01-1002
Yuichiro Murata, Tomoko Morita, Katsuji Wada, Hiroshi Ohno
Abstract A new concept for trapping NOx and HC during cold start, the NOx Trap Three-Way Catalyst (N-TWC), is proposed. N-TWC adsorbs NOx at room temperature, and upon reaching activation temperature under suitable air-fuel ratio conditions, it reduces the adsorbed NOx. This allows a reduction in NOx emissions during cold start. N-TWC's reduction mechanism relies on NOx adsorption sites which are shown to be highly dispersed palladium on acid sites in the zeolite. Testing on an actual vehicle equipped with N-TWC confirmed that N-TWC is able to reduce emissions of NOx and HC during cold start, which is a challenge for conventional TWCs.
2015-04-14
Journal Article
2015-01-1006
Joseph R. Theis, Jeong Kim, Giovanni Cavataio
Abstract A laboratory study was performed to assess the potential capability of TWC+LNT/SCR systems to satisfy the Tier 2, Bin 2 emission standards for lean-burn gasoline applications. It was assumed that the exhaust system would need a close-coupled (CC) TWC, an underbody (U/B) TWC, and a third U/B LNT/SCR converter to satisfy the emission standards on the FTP and US06 tests while allowing lean operation for improved fuel economy during select driving conditions. Target levels for HC, CO, and NOx during lean/rich cycling were established. Sizing studies were performed to determine the minimum LNT/SCR volume needed to satisfy the NOx target. The ability of the TWC to oxidize the HC during rich operation through steam reforming was crucial for satisfying the HC target.
2015-04-14
Journal Article
2015-01-1714
Usman Asad, Jimi Tjong
Abstract This study describes a zero-dimensional algorithm for tracking the intake dilution in real-time. The inputs to the model are the oxygen concentration from the exhaust oxygen sensor, the manifold air pressure and temperature (MAP/MAT), the mass air flow (MAF) and the estimated fuel injected per cycle from the engine control module. The intake manifold, the exhaust manifold and EGR system are discretized into 3 volumes and the detailed concentrations of the gas species comprising the exhaust, EGR and intake streams are tracked at each time step (on a cycle-by-cycle basis). The model does not need the EGR ratio to be known in advance and is also applicable to oxygenated fuels such as ethanol. The model response is tuned to a multi-cylinder engine and the model output is empirically validated against a wide range of engine operations including load and EGR transients.
2015-04-14
Journal Article
2015-01-1017
Yuki Jin, Narimasa Shinoda, Yosuke Uesaka, Tatsuyuki Kuki, Masataka Yamashita, Hirofumi Sakamoto, Tasuku Matsumoto, Philipp Kattouah, Claus Dieter Vogt
Abstract Since the implementation of Euro 6 in September 2014, diesel engines are facing another drastic reduction of NOx emission limits from 180 to only 80 mg/km during NEDC and real driving emissions (RDE) are going to be monitored until limit values are enforced from September 2017. Considering also long term CO2 targets of 95 g/km beyond 2020, diesel engines must become cleaner and more efficient. However, there is a tradeoff between NOx and CO2 and, naturally, engine developers choose lower CO2 because NOx can be reduced by additional devices such as EGR or a catalytic converter. Lower CO2 engine calibration, unfortunately, leads to lower exhaust gas temperatures, which delays the activation of the catalytic converter. In order to overcome both problems, higher NOx engine out emission and lower exhaust gas temperatures, new aftertreatment systems will incorporate close-coupled DeNOx systems.
2015-04-09
WIP Standard
J3094
Create a standard for measurement of the performance characteristics of an Internal Heat Exchanger. The standard should make it easier to innovate designs and bring improvements to this new technology.
2015-04-08
Magazine
Hydraulics still in control of off-highway needs Engineers continue to master electronic controllers and software to help systems manage engine speeds and boost efficiency, to the ultimate benefit of both OEMs and end-users. Off-highway calibration challenges-big and complex As the final set of Tier 4 regulations kick in for engines greater than 750 hp (560 kW), calibration efforts must contend with complex engine and aftertreatment systems. Engine manufacturers and service providers deal with this complexity, but does it need to be so? DEF delivery modelling for SCR systems Researchers characterize a 0-D model of a urea delivery module, oriented to model-based control and to the simulation of the system response to fault injections finalized to diagnosis validation.
2015-03-30
Technical Paper
2015-01-0111
Sarapon Thitipatanapong, Sathaporn Chuepeng, Poranat Visuwan
Abstract Encouraging the use of alternative fuels available in Thailand is mainly due to fuel crisis within the past few decades. The government has recently drafted a renewable energy long-term plan to increase biofuel production. This has emboldened biodiesel to be used as fuel for agriculture and transportation, in particular. Diesel engines are promising for reducing carbon dioxide emissions related fuel energy consumption. Ordinarily, diesel combustion generates particulate matter and nitrogen oxides in trade-off relationship. However, advanced techniques for engine technology and aftertreatment devices have been abundantly developed to mitigate these hindrances. To break the trade-off emissions, an example technique is to fuel engines with biodiesel incorporated with exhaust gas recirculation. Among available options, nonthermal plasma (NTP) is one of the techniques that charges exhaust gas with high power electricity to reduce some emissions.
2015-03-30
Technical Paper
2015-01-0126
Meng Choung Chiong, Srithar Rajoo, Alessandro Romagnoli
Abstract This paper presents a concept for new piston expander utilizing nozzle as part of a secondary steam cycle to recover exhaust energy. A commercial 1D simulation tool, AVL BOOST, was used to model the system, and comparison study was carried out between the conventional and nozzle piston expanders. It was found the nozzle piston expander could increase output power from a minimum of 0.73kW up to a maximum of 4.75kW. The simulation study has shown that the concept of using nozzle to admit steam into the piston expander has potential to improve engine system level efficiency.
2015-03-27
Article
Sales of diesel-powered light vehicles are up 70% and the latest engines are cleaner than ever. But the diesel industry still faces significant headwinds to greater penetration.
2015-03-25
Article
A team of researchers from the Cockrell School of Engineering at The University of Texas at Austin have developed a mutant yeast strain that could lead to a more efficient and economical biofuel production process, and from non-food sources.
2015-03-13
Article
Andy Pontius, Chief Technologist for Faurecia Emissions Control Technologies in North America, talks about even lighter-weight exhaust systems and meeting future powertrain-systems expectations.
2015-03-11
Article
Novel aluminum-rich steel alloy could find structural use in road vehicles and even aircraft.
2015-03-10
Technical Paper
2015-01-0009
Bingjie Zhang, Siti Khalijah Mazlan, Shuheng Jiang, Alberto Boretti
Abstract With the purpose of reducing emission level while maintaining the high torque character of diesel engine, various solutions have been proposed by researchers over the world. One of the most attractive methods is to use dual fuel technique with premixed gaseous fuel ignited by a relatively small amount of diesel. In this study, Methane (CH4), which is the main component of natural gas, was premixed with intake air and used as the main fuel, and diesel fuel was used as ignition source to initiate the combustion. By varying the proportion of diesel and CH4, the combustion and emissions characteristics of the dual fuel (diesel/CH4) combustion system were investigated. Different cases of CFD studies with various concentration of CH4 were carried out. A validated 3D quarter chamber model of a single cylinder engine (diesel fuel only) generated by using AVL Fire ESE was modified into dual fuel mode in this study.
2015-03-10
Technical Paper
2015-01-0018
Dongwon Yeon
Abstract There are some problems “windows fog up a lot” for ventilation system. We have Test Development Procedure to prevent the fog problems. But, Many fog problems occurred in the cars that we made. So in this paper, new ventilation system is needed and developed. The Smart Ventilation System automatically controls indoor air quality even though the blower motor is off. There are two sensors that is used for AutoDefogSensor system and CO2 CONTROL system.. The sensor is on when blower motor and heater control is off. We use these signals and make new ventilation logics. We evaluate this system in chamber & '13 winter test in USA.
2015-03-10
Technical Paper
2015-01-0051
Bradley Glenn Orr, Aliakbar Akbarzadeh, Petros Lappas
Abstract Exhaust heat recovery systems are used to make use of otherwise wasted heat from a car engine. The purpose of exhaust heat recovery systems is to reduce the fuel consumption of the car and consequently reduce CO2 emissions. The unique system design described herein utilises thermoelectric generators (TEGs) and heat pipes with its key advantage being it is a passive solid state design. The use of these components creates a few design constraints. For example, both the TEGs and heat pipes have operating temperature limitations. In this paper, a naphthalene heat pipe preheat exchanger is proposed to deal with this problem. Exhaust conditions measured from a representative spark ignition engine were used in a numerical simulation to predict the performance of the exhaust heat recovery system. If 8 modules are used and the engine is producing 8kW of mechanical power, the system is predicted to produce 53.75W of electrical power.
2015-03-10
Technical Paper
2015-01-0057
Jooyoung Park, Daehyun Choi, Yeonsik Kang, Seangwock Lee, Yongseok Cho, Taemin Kim
Abstract In this study, SCR system is employed to selectively reduce NOX that is a major cause of environmental pollution from diesel engines. In particular, this paper focuses on urea injection strategies dependent on NO/ NOX ratio. An injection control algorithm is developed based on the chemical ratio between the amount of engine out NOX data obtained from Engine Management System (EMS) and the amount of NH3. Therefore, in order to decide the amount of injection quantity, the NO/NOX ratio from the engine out NOX should be considered in order to minimize NH3 slip while maximizing NOX reduction. Experiments are conducted with a 2.2-liter diesel engine for passenger vehicles with Diesel Oxidation Catalyst (DOC) and Diesel Particle Filter (DPF). Real time control, using Pulse Width Modulation (PWM) duty ratio for dosing module and supply module, is performed by real time computer with its injection control algorithm developed in the Matlab Simulink environment.
2015-03-10
Technical Paper
2015-01-0058
Robin Smit, Phil Kingston
Abstract Reliable motor vehicle emission predictions are needed to ensure sound policy decisions. This study reports on a comparison between measured in-tunnel fleet emissions and predictions made with two new Australian vehicle emission software programs (COPERT Australia and PΔP) for one air pollutant: nitrogen oxides (NOx). Measurements were taken from a 6.8 km tolled motorway tunnel that links several major roads in Brisbane, Australia. The validation study suggests that modelled vehicle emissions of NOx are similar to those measured in the tunnel with a prediction error less than ±25% for both light-duty and heavy-duty vehicles. A possible reason for the difference is a suspected younger and cleaner fleet in the tunnel as compared with the Queensland average fleet. Further analysis of license plate information is anticipated to verify this.
2015-03-10
Technical Paper
2015-01-0056
Thanthep Puphunwivat
Abstract Today heavy duty trucks, passenger cars and non-road machinery are certified in emission labs via common legislative test cycles. Recent benchmark studies clearly show that the real driving emissions of vehicles highly exceed the regulatory emission limits which are used for the certification on the test cycles. It was found that this gap was even further increasing over the past decade for passenger cars. EPA introduced Portable Emission Measurement Systems (PEMS) testing on the road for heavy duty trucks already since 2007 followed by Europe in 2013 with EU VI to tackle this problem. Now European Commission is introducing first time the similar approach for passenger cars with the real driving emission regulation (RDE) from EU6b (September 2014) on. RDE is imposing new challenges and complexity on today's approach for the development of vehicles and engines.
2015-03-10
Technical Paper
2015-01-0055
Neeraj Kumar, Prashant Kumar, M. Sithananthan, Reji Mathai, Ajay Kumar Sehgal, R. Suresh, B. P. Das
Abstract Volatile Organic Compounds (VOCs) present in ambient air are potentially toxic among the air pollutants. They are present in the urban atmosphere due to both exhaust emissions from vehicles and evaporative emissions at fuel filling stations. The present study aims to provide an indication of ambient levels of benzene, a carcinogenic VOC in the immediate vicinity of petrol filling stations in Delhi & National Capital Region (NCR). The monitoring of benzene is conducted across the vicinity of petrol stations to ascertain the effect of outside pollutant concentration on forecourt area. Continuous monitoring of benzene was achieved by an air quality monitoring facility stationed across the selected locations at four selected fuel filling stations. It was observed that the average concentrations of benzene measured during the study ranged between 2.28 ppb - 9.43 ppb.
2015-03-05
Article
Tightening vehicle efficiency and emissions regulations and increasing demand for onboard electrical power means that higher voltages, in the form of supplemental 48-volt subsystems, may soon be nearing production.
2015-03-03
Magazine
Virtual casting improves powertrain design As designers continue to look for ways to cut weight and increase performance, casting simulations are helping optimize designs through faster, more accurate predictions of the casting process used to create key components. Horse racing America's pony cars are a favorite of racers and fans alike, so racing them against each other is natural. SAE 2015 World Congress Preview Tech trends and exhibitor products are highlighted. Tech trends and exhibitor products are highlighted in this special section, which features an exclusive interview with Honda R&D America's Jim Keller. Replicating the racing experience Professional driving simulators can be successfully exploited to shorten the traditional design-prototype testing-production process relative to a new racecar.
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