Display:

Results

Viewing 31 to 60 of 24423
2017-03-28
Technical Paper
2017-01-0991
Sunil Kumar Pathak, Yograj Singh, Vineet sood, Salim Abbasbhai Channiwala
Presently, regulatory emission and fuel consumption values for new car are determined by a type-approval process. Several studies have shown that the type-approval data is not representative for real-world usage. The working group designated as Real Driving Emissions – Light Duty Vehicle (RDE-LDV) assessing the potential of two candidate testing procedures: Emission testing with random driving cycles in the laboratory, and on-road emissions testing with Portable Emissions Measuring Systems (PEMS) as real driving test procedure. The recent reports concluded that both PEMS and random cycle testing are technically feasible. The random cycle testing is more effective than emissions testing with the NEDC, but potentially cover a smaller range of driving conditions but it allows use of established, accurate analytical equipment, and enables the repetition and reproduction of individual emission tests under defined conditions.
2017-03-28
Technical Paper
2017-01-1217
Jiangong Zhu, Zechang Sun, Xuezhe Wei, Haifeng Dai
An alternating current (AC) heating method for a NMC lithium-ion battery with 8Ah capacity is proposed in the paper. The effects of excitation frequency, current amplitudes, and voltage limit condition on the temperature evolution are investigated experimentally. Current amplitudes are set to 24A(3C), 40(5C), and 64A(8C), and excitation frequencies are set to 300Hz, 100Hz, 30Hz, 10Hz, 5Hz, and 1Hz respectively. The voltage limitations are necessary to protect cells from overcharge. Therefore the voltage limit condition (4.2V/2.75V, 4.3V/2.65V, and 4.4V/2.55V) are also considered in depth to verify the feasibility of the AC heating method. The temperature rises prominently as the current increases, and the decrement of frequencies also lead to the obvious growth of battery temperature. The battery obtains the maximum temperature rise at 64A and 1Hz, which takes 1800s to heat up the battery from -25oC to 18oC.
2017-03-28
Technical Paper
2017-01-0123
Saiful Bari
In general, diesel engines have an efficiency of about 35% and hence, a considerable amount of energy is expelled to the ambient air. In water-cooled engines, about 25%, 33% and 7% of the input energy are wasted in the coolant, exhaust gas, and friction, respectively. The heat from the exhaust gas of diesel engines can be an important heat source to provide additional power and improve overall engine efficiency. Studies related to the application of recoverable heat to produce additional power in medium capacity diesel engines (< 100 kW) using separate Rankine cycle are scare. To recover heat from the exhaust of the engine, an efficient heat exchanger is necessary. For this type of application, the heat exchangers are needed to be designed in such a way that it can handle the heat load with reasonable size, weight and pressure drop. This paper describes the study of a diesel generator-set attached with an exhaust heat recovery system.
2017-03-28
Technical Paper
2017-01-1020
Finn Tseng, Imad Makki, Pankaj Kumar, Robert Jentz, Aed Dudar
Engine-Off Natural Vacuum (EONV) principles based leak detection monitors are designed to determine the presence of a small leak in the fuel tank system. It was introduced to address the ever more stringent emission requirement (currently at 0.02”) for gasoline engine equipped vehicles as proposed by the Environmental Protection Agency (EPA) and California Air Resources Board (CARB) in the United States [2, 3]. Other environmental protection agencies including the ones in EU and China will be adopting similar regulations in the near future. Due to its sensitivity to known noise factors such as the ambient temperature, barometric pressure, drive pattern and parking angle, it has been historically a lower performing monitor that is susceptible to warranty cost or even voluntary recalls. The proposed new model based monitor utilizes production pressure signal and newly instrumented temperature sensors [15].
2017-03-28
Technical Paper
2017-01-0531
Rani Kiwan, Anna Stefanopoulou, Jason Martz, Gopichandra Surnilla, Imtiaz Ali, Daniel Styles
Low Pressure (LP) Exhaust Gas Recirculation (EGR) promises fuel economy benefits at high loads in turbocharged SI engines as it allows better combustion phasing and reduces the need for fuel enrichment. Precise estimation and control of in-cylinder EGR concentration is crucial to avoiding misfire. Unfortunately, EGR flow rate estimation using an orifice model based on the EGR valve ΔP measurement can be challenging given pressure pulsations, flow reversal and the inherently low pressure differentials across the EGR valve. Using a GT-Power model of a 1.6~L GDI turbocharged engine with LP-EGR, this study investigates the effects of the ΔP sensor gauge-line lengths and measurement noise on LP-EGR estimation accuracy. Gauge-lines can be necessary to protect the ΔP sensor from high exhaust temperatures, but unfortunately can produce acoustic resonance and distort the ΔP signal measured by the sensor.
2017-03-28
Technical Paper
2017-01-1012
Sunil Kumar Pathak, Vineet sood, Yograj Singh, Salim Abbasbhai Channiwala
In developing countries like India, large numbers of portable gesnets are used as power source due to scarcity of grid power supply. The portable gensets, ranging fron 0.5 kW to 5 kw are very popular in the residential, small restaurants and shopping complexes. These gensets are using various fuels like gasoline, diesel, LPG and kerosene for small spark ignited and compression ignition engines and significant source of air pollution as these are running close to populated areas. Theses gensets are regulated by exhaust and noise emissions norms set by statutory bodies like central pollution control board of India. The gaseous emissions of carbon monoxide (CO), total hydrocarbon (THC) and nitrogen oxides (NOx) and particulate matter (PM) are regulated and emission testing is performed as per three mode cycle as per standard test proecdure. The production gesnets are normally undergo a break in running to stabilize engine performance parameters mainly engine power output.
2017-03-28
Technical Paper
2017-01-0707
Srinivas Padala, Minh Khoi Le, Yoshihiro Wachi, Yuji Ikeda
The effect of microwave enhanced plasma (MW Plasma) on diesel spray combustion was investigated inside a constant volume high pressure chamber. A microwave-enhanced plasma system, in which plasma discharge generated by a spark plug was amplified using microwave pulses, was used to introduce plasma. Initially, the plasma was introduced to the diesel spray before the occurrence of auto-ignition, to understand the effect of additional oxidizer entertainment on ignition delay of diesel spay. High speed imaging of natural luminosity indicated an earlier appearance of flame in the with-plasma cases compared to the respective without-plasma conventional operation. These results corresponds well to the behavior of the heat-release rates, suggesting a reduction-effect by MW plasma on the ignition delay of diesel combustion. Later, the plasma was introduced downstream the flame lift-off and in the soot cloud to estimate the soot reduction effect by plasma.
2017-03-28
Technical Paper
2017-01-0931
Michiel Van Nieuwstadt, Joseph Ulrey
While not commonly in production today, Gasoline Particulate Filters (GPFs) are likely to see widespread deployment to meet stringent EU6.2 and China particulate number (PN) standards. In many ways the operating conditions for GPFs are orthogonal to those of their diesel counterparts, and this leads to different and interesting requirements for the control strategy. We will present some generic system architectures for exhaust systems containing a GPF and will lay out an architecture for the GPF control strategy components which include: regeneration assist feature, soot estimation algorithm, GPF protection. Lastly, we will show validation data of the control strategy under different operating conditions.
2017-03-28
Technical Paper
2017-01-0963
Hoon Cho, Thomas Brewbaker, Devesh Upadhyay, Brien Fulton, Michiel Van Nieuwstadt
Many excellent papers have been written about the subject of estimating engine-out NOx on diesel engines based on real-time available data. The claimed accuracy of these models is typically around 6-10% on validation data sets with known inputs. This reported accuracy typically ignores the uncertainty around the inputs, thus arriving at an optimistic estimate of the model accuracy in a real-time application. In our paper we analyze the effect of uncertainty on the accuracy of engine-out NOx estimates via a numerical Monte Carlo simulation and show that this effect can be significant. Even though our model is based on an in-cylinder pressure sensor, this sensor is limited in its capability to reduce the effect of other measured inputs to the model. We give a brief presentation of the model and focus on the uncertainty analysis.
2017-03-28
Technical Paper
2017-01-0721
Michele Bardi, Gilles Bruneaux, André Nicolle, Olivier Colin
This paper is a contribution to the understanding of the formation and oxidation of soot in typical Diesel combustion. A common rail ECN spray A injector (single axial-oriented orifice) was tested in a optically accessible test-chamber at engine relevant conditions. High-speed OH* and high-speed 2D extinction imaging were performed simultaneously to link together the flame chemistry and the soot data information. The experiments were carried out for different fuels (EU Diesel, JetA1, n-dodecane) performing parametric variations of the boundary conditions. The proposed analysis methodology enabled the identification of the sooting behavior of each fuel by evaluating the relationship between two of the measured parameters, namely lift-off length and the soot maximum axial extinction value (Max KL). The relationship between these two parameters allowed to distinguish the behavior of the different fuels.
2017-03-28
Technical Paper
2017-01-0084
Jiantao Wang, Bo Yang, Jialiang Liu, Kangping Ji, Qilu Wang
Studies show that driving in foggy environment is a security risk, and when driving in foggy environment, the drivers are easy to accelerate unconsciously. The safety information prompted to the driver is mainly from fog lights, road warning signs and the traffic radio. In order to increase the quality of the safety tips to prevent drivers from unintended acceleration and ensure the security of driving in foggy environment, the study proposes a safety speed assessment method for driving in foggy environment, combining the information of driving environment, vehicle’s speed and the multimedia system.The method uses camera which is installed on the front windshield pillar to collect the image about the environment, and uses the dark channel prior theory to calculate the visibility. And by using the environment visibility, the safety speed can be calculated based on the kinematics theory. And it is appropriate for vehicles which have different braking performance.
2017-03-28
Technical Paper
2017-01-0636
Vijai Shankar Bhavani Shankar, Nhut Lam, Arne Andersson, Bengt Johansson
The concept of double compression, and double expansion stages (DCEE) for improving the efficiency of piston reciprocating engines was introduced in SAE Paper 2015-01-1260. This engine configuration separates high, and low pressure units thereby effectively reducing friction losses. The presence of an additional expander stage also allows an extra degree of freedom to manipulate the combustion heat release rate so as to achieve better optimum between heat transfer, and friction losses. This paper presents a 1-D modeling study of the engine concept in GT-Power for assessing the sensitivity of engine losses to heat release rate at a given speed-load point. The simulations were constrained by limiting the range of maximum motoring pressures from 200 bar to 300 bar, and the maximum pressure during combustion to 300 bar. The maximum motor pressure was varied by constraining the compression ratio of the high pressure unit and adapting the low pressure unit accordingly.
2017-03-28
Technical Paper
2017-01-0872
Sunil Kumar Pathak, Vineet sood, Yograj Singh, Shubham Gupta, Salim Abbasbhai Channiwala
In this study, A Gasoline Passenger car (Euro IV) was experimentally investigated for performance and emissions on three different fuels i.e. Gasoline, (Liquefied Petroleum Gas) and DME (Di-methyl ether) blend with concentration of 20% by mass in LPG (DME20). In particular, emission characteristics (including Hydrocarbon, CO, NOx and CO2) over the Modified Indian Driving Cycle (MIDC) and fuel economy were investigated at the Vehicle Emission Laboratory (VEL) at the CSIR- Indian Institute of Petroleum, Dehardun, India. The experimental results showed that Vehicle comply with Euro IV legislation on gasoline and LPG fuel showed higher NOx Emissions on DME 20 fuel. LPG kit was reconfigured for DME and LPG blend to bring down the emissions within the specified emission limits. The Emission values observed for DME20 were 0.635 g/km (CO), 0.044 g/km (THC), and 0.014 g/km (NOx) against the Euro IV limits of 1.0 g/km, 0.1 g/km and 0.08 g/km, respectively.
2017-03-28
Technical Paper
2017-01-0606
Ashley Wiese, Anna Stefanopoulou, Julia Buckland, Amey Y. Karnik
Low-Pressure Exhaust Gas Recirculation (LP-EGR) has been shown to be an effective means of improving fuel economy and suppressing knock in downsized, boosted, spark ignition engines. LP-EGR is particularly beneficial at low-speed, high-load conditions, but can lead to combustion instability at lower loads. The transport delays inherent in LP-EGR systems slow the reduction of intake manifold EGR concentrations during tip-out events, which may lead to excessive EGR concentrations at low load. This paper explores leveraging Variable Valve Timing (VVT) as a means of improving the rate of reduction of intake manifold EGR concentration prior to tip-out. At higher boost levels, high valve overlap may result in intake manifold gas passing directly to the exhaust manifold. This short-circuiting behaviour could potentially improve EGR evacuation rates.
2017-03-28
Technical Paper
2017-01-0160
Longjie Xiao, Tianming He, Gangfeng Tan, Bo Huang, Xianyao Ping
In the background of the increasing amount of car ownership in the world, the amount of heat that is not utilized in automobile exhaust should not be ignored, and the importance of using automobile exhaust gas for power generation is gradually being realized and valued by people. However, the urban traffic environment is changeable. The frequent start and stop as well as the acceleration and deceleration of the car will lead to the fluctuation of gas temperature and flow and then the temperature fluctuation of the thermoelectric module’s hot end, which reduces the power generation efficiency of thermoelectric module. By arranging the heat conduction oil circulation at the hot end, the temperature fluctuation of the hot end of thermoelectric module can be effectively reduced, but the system volume is large, and the working fluid circulation needs additional energy supply.
2017-03-28
Technical Paper
2017-01-0135
Jose Grande, Julio Abraham Carrera, Manuel Dieguez Sr
Exhaust Gas Recirculation system (EGR) is an effective technique for reducing NOx emissions in order to accomplish the more and more stringent emissions standards. This system is widely use in commercial vehicle engines in which thermal loads and durability are a critical issue. In addition, the development deadlines of the new engine generations are being considerably reduced, especially for validation test phase in which costumers usually require robust parts for engine validation in the first stages of the project. Some of the most critical issues in this initial phases of program development are heavy boiling and thermal fatigue. Consequently, it has been necessary to develop a procedure for designing EGR coolers robust enough against heavy boiling and thermal fatigue in a short period of time, even when the engine calibration is not finished and the working conditions of the EGR system are not completely defined.
2017-03-28
Technical Paper
2017-01-1006
Fadzli Ibrahim, Wan Mohd Faizal Wan Mahmood, Shahrir Abdullah, Mohd Radzi Abu Mansor
The undisputable advantages in terms of time and cost saving for soot emission study have made the computational analyses becomes more preferable. Current development of computer program with higher precision mathematical model making simulation works becomes closer to the real engine combustion environment. This investigation for in-cylinder soot concentration has been carried out using a commercial Computational Fluid Dynamic (CFD) software, CONVERGE CFD. In conjunction to explore its full capability, study on soot has been performed using different level of complexity soot model, from simple two-steps of Hiroyasu-NSC soot model to the detailed-kinetic soot model. Both detailed soot model which based on methods of moment and sectional method are applied in this study.
2017-03-28
Technical Paper
2017-01-0127
Norimitsu Matsudaira, Mitsuru Iwasaki, Tatsuya arai, Yasuo Moriyoshi, Naohiro hasegawa, Junichiro Hara, Tomohiko furuhata
Among the emerging technologies in order to meet ever stringent emission and fuel consumption regulations, Exhaust Gas Recirculation (EGR) system is becoming one of the prerequisites particularly for diesel engines. Although an EGR cooler is considered to be an effective measure for further performance enhancement, exhaust gas soot deposition may cause degradation of the cooling. To address this issue, the authors studied the visualization of the soot deposition phenomenon to understand its behavior. Based on thermophoresis theory, which indicates that the effect of thermophoresis depends on the temperature difference between gas and the wall surface exposed to the gas, a new visualization method using a heated glass window was developed. By using glass with the transparent conductive oxide: tin-doped indium oxide , temperature of the heated glass surface is raised.
2017-03-28
Technical Paper
2017-01-0154
Sudhi Uppuluri, Hemant R Khalane, Ajay Naiknaware
With the upcoming regulations for fuel economy and emissions, there is a significant interest among vehicle OEMs and fleet managers in developing computational methodologies to help understand the influence and interactions of various key parameters on Fuel Economy and carbon-di-oxide emissions. The analysis of the vehicle as a complete system enables designers to understand the local and global effects of various technologies that can be employed for fuel economy and emission improvement. In addition, there is a particular interest in not only quantifying the benefit over standard duty-cycles but also for real world driving conditions. This study looks at the impact of exhaust heat recovery system (EHRS) on a small passenger car in the India market with a 1.2L naturally aspirated gasoline engine. CSEG has developed a forward looking Simulink model of the passenger car in order to calculate the engine loading, engine heat rejection and the exhaust energy being generated.
2017-03-28
Technical Paper
2017-01-0984
Wenran Geng, Diming Lou, Ning Xu, Piqiang Tan, Zhiyuan Hu
Recently Hybrid Electric Buses have been widely used in China. In order to study their emissions reduction effects, the exhaust emissions of an in-use diesel-electric hybrid bus have been evaluated both over China City Bus Cycles (CCBC) on chassis dynamometer and on the road using Portable Emissions Measurement Systems (PEMS). The diesel-electric hybrid bus adopts a coaxial parallel mode hybrid system and is driven by electric motor at 0~20km/h while engine keeps idling. Only if the vehicle speed exceeds 20km/h, engine and electric motor will provide driving force together, which leads to more violent transient conditions of engine. Firstly, exhaust emissions of the diesel-electric hybrid bus and a Chinese V stage bus with traditional powertrain have been tested on heavy chassis dynamometer over CCBC.
2017-03-28
Technical Paper
2017-01-1014
David Moyer, Roger Khami, Andrew Bellis, Thomas Luley
Engine Air Induction Systems Hydrocarbon Trap (HC Trap) Designs, to limit evaporative fuel emissions, have evolved over time. This paper discusses a range of HC Traps that have evolved in Engine Air Induction Systems. (AIS) The early Zeolite Flow through Hydrocarbon Trap utilized an exhaust catalyst technology internal stainless steel furnace brazed substrate coated with Zeolite media. This HC Trap was installed in the AIS Clean Air Tube. This design was heavy, complicated, and expensive but met the urgency of the implementation of the new evaporative emissions regulation. The latest Ford Motor Company HC Trap is a simple plastic tray containing activated carbon with breathable non-woven polyester cover. This design has been made common across multiple vehicle lines with planned production annual volume in the millions. The cost of the latest HC Trap Bypass design is approximately 5% of the original Stainless Steel Zeolite Flow Through HC Trap.
2017-03-28
Technical Paper
2017-01-0702
Raouf Mobasheri, Mahdi Seddiq
The simultaneous effects of pilot fuel quantity and pilot injection timing on engine performance and amount of pollutant emission have been computationally investigated in a High Speed Direct Injection (HSDI) diesel engine. In this study, a modified parameter called “Homogeneity Factor of in-cylinder charge (HF)” has been applied to analyze the air-fuel mixing and combustion processes. For this purpose, the simulated results has been firstly compared with the experimental data and a good agreement has been achieved for simulating the in-cylinder pressure and the amount of pollutant emissions. Then, nine different strategies based on two variables (the amount of fuel mass in pilot and main injection as well as the dwell between two injections) have been investigated. The results show that employing pilot injection results in higher in-cylinder temperature and shorter auto-ignition delay which causes a rapid increase in the rate of NOx formation in early stage of combustion process.
2017-03-28
Technical Paper
2017-01-0679
Kelvin Xie, Shui Yu, Xiao Yu, Geraint Bryden, Ming Zheng, Mengzhu Liu
In order to meet the future carbon dioxide legislation, advanced clean combustion engines are tending to employ low temperature diluted combustion strategies along with intensified cylinder charge motion. The diluted mixtures are made by means of excess air admission or exhaust gas recirculation. A slower combustion speed during the early flame kernel development because of the suppressed mixture reactivity will reduce the reliability of the ignition process and the overall combustion stability. In an effort to address this issue, an ignition strategy using a multi-pole spark igniter is tested in this work. The igniter uses three electrically independent spark gaps to allow three spatially distributed spark discharge. The presence of the three independent poles offers the possibility for the poles to spark at the same time, sequentially, or to be reserved for instrumentation purposes.
2017-03-28
Technical Paper
2017-01-0741
Xinlei Liu, Laihui Tong, Hu Wang, Zunqing Zheng, Mingfa Yao
In this work the gasoline compression ignition (GCI) combustion characterized by the premixed gasoline port injection and gasoline direct injection in a single-cylinder diesel engine was investigated experimentally and computationally. In the experiment, the premixed ratio, injection strategy, and exhaust gas recirculation (EGR) rates were varied with the pressure rise rates below10 bar/crank angle. The experimental results showed that the higher premixed ratio and earlier injection timing with high injection pressure resulted in advanced combustion phasing and improved thermal efficiency, while the pressure rise rates and NOx emissions increased. The soot, HC, and CO emissions decreased with higher injection pressure and earlier injection timing, while the HC emission increased significantly with higher premixed ratio. With the increase of EGR, the soot and NOx emissions decreased while the CO and HC emissions increased significantly.
2017-03-28
Technical Paper
2017-01-0783
Hamid R. Rahai, Yong Lee, Najmeh rahimi, Komal Gada
Numerical and experimental investigations of the effect of a humid air system on nitrogen oxides (NOx) and Particulate Matter (PM) emissions of a compressed natural gas (CNG) engine have been performed. For the numerical modeling, non-premixed combustion in a single cylinder was simulated using the presumed probability density function combustion model. Simulations were performed for dry as well as humid intake air at 10%, 15%, and 30% relative humidity. Numerical results have shown 40% reduction in NO emission at 10% relative humidity, when compared with emissions of dry intake air. With 15% and 30% relative humidity levels, NO emission were reduced by 65% and 93% respectively. For experimental investigations, a General Motors inline 4 cylinders, naturally aspirated engine with a maximum rated horsepower (HP) of 50.8 for natural gas fuel was used. The engine was connected to a water-cycled dynamometer.
2017-03-28
Technical Paper
2017-01-0921
Bharadwaj Sathiamoorthy, Alex Graper, Andrew McIntosh, William Kaminski
The automotive aftermarket industry is an extremely cost competitive market to say the least. Aftermarket manufacturers are sought by customers primarily for their ability to replace an OES for a fraction of the cost. This pressurizes the manufacturers to yield on performance abilities to get a share in the market place. The TWC system in gasoline vehicles not only acts as an emissions reduction device but is an integral part of the overal vehicle performance itself, especially since the introduction of OBD II systems in 1995. An inefficient catalyst not only leads to excessive tailpipe emissions but also acts detrimental to vehicle fueling and hence overall performance. The aftemarket catalyst industry which is regulated by EPA and CARB for gasoline engines is subject to meeting a mandatory performance standard for the same reason. There are several advancement in catalyst technologies to gain performance but this may or may not apply to the aftermarket manufacturers.
2017-03-28
Technical Paper
2017-01-0941
Liu Yang, Balaji Sukumar, Mojghan Naseri, Penelope Markatou, Sougato Chatterjee
Future emissions regulations proposed for the Asian automotive industry (BSVI for India and NSVI regulations for China) are strict and similar to EU VI regulations. As a result, they will require both advanced NOx control as well as advanced Particulate Matter (PM) control. This will drive implementation of full Catalyzed Soot Filter (CSF) and simultaneous NOx control using Selective Catalytic Reduction (SCR) technologies. In this work, we present the performance of various Diesel Oxidation Catalyst (DOC), CSF, SCR and Ammonia slip catalyst (ASC) systems utilizing the World Harmonized Transient Cycle (WHTC). Aftertreatment Systems (ATS) required for both active and passive filter regeneration applications will be discussed. The sensitivity of key design parameters like catalyst technology, PGM loading, catalyst sizing to meet the regulation limits has been investigated.
2017-03-28
Technical Paper
2017-01-0932
Nehemiah S I Alozie, George Fern, David Peirce, Lionel Ganippa
ABSTRACT The use of diesel particulate filter (DPF) has become a standard after treatment technology in modern diesel engine however; pressure drop develops across the filter as PM accumulates. This requires quick periodic burn-out without incurring thermal runaway temperatures that could compromise DPF integrity in operation. Adequate understanding of soot oxidation is central to design and manufacture of efficient filter traps suitable for the engine system. In this study, we have examined the oxidation of PM generated from a high speed direct injection (HSDI) diesel engine, ran with 20% and 40% blends of two biodiesel fuels. The PM samples were collected on a Pall Tissuquartz filter during constant engine load and oxidised non-isothermally in a thermogravimetric analyser (TGA). Then results obtained are compared with PM oxidation data obtained from pure petrodiesel.
2017-03-28
Technical Paper
2017-01-0969
Alois Danninger, Ismar Mustedanagic, Martin Herbst, Christoph Kreuzberger, Peter Lichtenberger, Armin Wabnig, Josef Zehetner, Georg Macher, Eric Armengaud
Reduction of fuel consumption and greenhouse gas emission is a challenge for our society as both targets shall be reached without drawback on mobility or freight transport. A promising approach to achieve this challenging target is the improvement of exhaust after-treatment control strategy – tightly coordinated with the respective engine. In this paper, a smart environment for the efficient validation of innovative exhaust after-treatment control strategies is proposed. The motivation is to provide a hybrid environment (mixing simulation and physical components) to reduce validation efforts and costs without impacting the representativeness of the test vectors.
2017-03-28
Technical Paper
2017-01-0949
Makoto Ito, Mitsuru Sakimoto, Zhenzhou Su, Go Hayashita, Keiichiro Aoki
New two-A/F systems different from usual A/F-O2 systems are being developed to cope with strict regulation of exhaust gas. In the two-A/F systems, two A/F sensors are equipped in front and rear of a three-way catalyst. The A/F-O2 systems are ideas which use a rear O2 to detect exhaust gas leaked from three-way catalyst early and feed back. On the other hand, the two-A/F systems are ideas which use a rear A/F sensor to detect nearly stoichiometric gas discharged from the three-way catalyst accurately, and to prevent leakage of exhaust gas from the three-way catalyst. Therefore, accurate detection of nearly stoichiometric gas by the rear A/F sensor is the most importrant for the two-A/F systems. In general, the A/F sensors can be classified into two types, so called, one-cell type and two-cell type. Because the one-cell type A/F sensors don’t have hysteresis, they have potential for higher accuracy.
Viewing 31 to 60 of 24423

Filter