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Viewing 241 to 270 of 23256
2016-04-05
Journal Article
2016-01-0914
Yaritza M. López - De Jesús, Peter I. Chigada, Timothy C. Watling, Kaneshalingam Arulraj, Anna Thorén, Neil Greenham, Penelope Markatou
Abstract Future heavy-duty diesel (HDD) engines are designed to have higher engine out NOx, for improved fuel economy, while reduction of the emission control technology footprint is also desired. Consequently, higher NOx reduction across compact emission control systems is required. Selective catalytic reduction (SCR) catalyst coating combined with a wall flow particulate filter (SCRF®1) is a technology that enables abatement of NOx emissions in addition to oxidation of soot from diesel engine exhausts. Vanadia based-SCR is well known for NOx reduction and is active for hydrocarbon (HC) and particulate matter (PM) oxidation. This dual functionality (oxidation and reduction reactions) of the V.SCR catalysts plus the filtration achieved by the filter substrate can help certain diesel engine applications achieve the legislative limits with a reduced packaging volume.
2016-04-05
Journal Article
2016-01-0911
Makoto Nagata, Takashi Yamada, Ryuji Ando, Insu Kim, Toshihisa Tomie
Abstract Commercial three way catalysts (TWC) are designed to eliminate HC, CO and NOx pollutants emitted from gasoline powered internal combustion engines. TWC have been optimized over many years to meet ever more stringent emission regulations. It has long been speculated that surface electrical conductivity may be a key parameter in controlling catalytic activity, however until now it has not been possible to reliably measure this physical parameter on a catalytic surface. In this study, the surface electrical conductivity of catalyst powders, such as Rh/ CeO1-x-ZrxO2, Rh/ZrO2 and Rh/Al2O3, were measured by EUPS (Extreme Ultraviolet excited Photoelectron Spectroscopy). Then the measured electrical conductivity was compared with catalyst performance from CO-NO and water gas shift reactions which are important for controlling automobile exhaust emissions from gasoline vehicles.
2016-04-05
Journal Article
2016-01-0961
Satish Narayanan Ramachandran, Gillis Hommen, Paul Mentink, Xander Seykens, Frank Willems, Frank Kupper
Abstract Heavy-duty diesel engines are used in a wide range of applications. For varying operating environments, the engine and aftertreatment system must comply with the real-world emission legislation limits. Simultaneously, minimal fuel consumption and good drivability are crucial for economic competitiveness and usability. Meeting these requirements takes substantial development and calibration effort, and complying with regulations results in a trade-off between emissions and fuel consumption. TNO's Integrated Emission Management (IEM) strategy finds online, the cost-optimal point in this trade-off and is able to deal with variations in operating conditions, while complying with legislation limits. Based on the actual state of the engine and aftertreatment system, an optimal engine operating point is computed using a model-based optimal-control algorithm.
2016-04-05
Journal Article
2016-01-1176
Karim Hamza, Ken Laberteaux
Abstract This work presents a modeling approach for estimation of the equivalent greenhouse gas (GHG) emissions of plugin hybrid electric vehicles (PHEVs) for real driving patterns and charging behaviors. In general, modeling of the equivalent GHG for a trip made by a PHEV not only depends on the trip trace in question, but also on the electric range of the vehicle and energy consumption in previous trips since the last charging event. This can significantly increase the necessary computational burden of estimating the GHG emissions using numerical simulation tools, which are already computationally-expensive. The proposed approach allows a trip numerical simulation starting with a fully charged battery to be re-used for GHG estimation of a trip that starts with any initial state of charge by re-allocating the appropriate amount electric energy to an equivalent gas consumption.
2016-04-05
Journal Article
2016-01-1152
Alan Brown, Marc Nalbach, Sebastian Kahnt, André Korner
Abstract Global CO2 reduction by 2021, according to some projections, will be comprised of multiple vehicle technologies with 7% represented by hybrid and electric vehicles (2% in 2014) [1]. Other low cost hybrid methods are necessary in order to achieve widespread CO2 reduction. One such method is engine-off coasting and regenerative braking (or recuperation) using a conventional internal combustion engine (ICE). This paper will show that a 48V power system, compared to a 12V system with energy storage module for vehicle segments B, D and E during WLTP and NEDC, is much more efficient at reducing CO2. Passive engine-off coasting using 12V energy storage shows a CO2 benefit for practical real world driving, but, during NEDC, multiple sources of friction slow the vehicle down to the extent that the maximum benefit is not achieved.
2016-04-05
Journal Article
2016-01-1192
Hisao Kato
Abstract Electrode catalyst (platinum) degradation represents a major challenge to the performance and durability of polymer electrolyte membrane fuel cells (PEMFCs) in Fuel Cell Vehicles (FCVs). While various mechanisms have been proposed and investigated previously, there is still a need to develop in situ imaging techniques that can characterize and provide direct evidence to confirm the degradation process. In the present study, we report an in situ transmission electron microscopy (TEM) method that enables real time, high-resolution observation of carbon-supported platinum nanoparticles in liquid electrolyte under working conditions. By improving the design of the Micro Electro Mechanical Systems (MEMS) sample holder, the migration and aggregation of neighboring platinum nanoparticles could be visualized consistently and correlated to applied electrode potentials during aging process (i.e., cyclic voltammetry cycles).
2016-04-05
Technical Paper
2016-01-0088
Tervin Tan, Jin Seo Park, Patrick Leteinturier
Abstract The constant motivation for lower fuel consumption and emission levels has always been in the minds of most auto makers. Therefore, it is important to have precise control of the fuel being delivered into the engine. Gasoline Port fuel injection has been a matured system for many years and cars sold in emerging markets still favor such system due to its less system complexity and cost. This paper will explain injection control strategy of today during development, and especially the injector dead-time compensation strategy in detail and how further improvements could still be made. The injector current profile behavior will be discussed, and with the use of minimum hardware electronics, this paper will show the way for a new compensation strategy to be adopted.
2016-04-05
Journal Article
2016-01-0183
Taehoon Han, Hyunki Sul, John Hoard, Chih-Kuang Kuan, Daniel Styles
Abstract Exhaust Gas Recirculation (EGR) coolers are commonly used in diesel and modern gasoline engines to reduce the re-circulated gas temperature. A common problem with the EGR cooler is a reduction of the effectiveness due to the fouling layer primarily caused by thermophoresis, diffusion, and hydrocarbon condensation. Typically, effectiveness decreases rapidly at first, and asymptotically stabilizes over time. There are several hypotheses of this stabilizing phenomenon; one of the possible theories is a deposit removal mechanism. Verifying such a mechanism and finding out the correlation between the removal and stabilization tendency would be a key factor to understand and overcome the problem. Some authors have proposed that the removal is a possible influential factor, while other authors suggest that removal is not a significant factor under realistic conditions.
2016-04-05
Journal Article
2016-01-0186
Hyunki Sul, Taehoon Han, Mitchell Bieniek, John Hoard, Chih-Kuang Kuan, Daniel Styles
Abstract Exhaust gas recirculation (EGR) coolers are used on diesel engines to reduce peak in-cylinder flame temperatures, leading to less NOx formation during the combustion process. There is an ongoing concern with soot and hydrocarbon fouling inside the cold surface of the cooler. The fouling layer reduces the heat transfer efficiency and causes pressure drop to increase across the cooler. A number of experimental studies have demonstrated that the fouling layer tends to asymptotically approach a critical height, after which the layer growth ceases. One potential explanation for this behavior is the removal mechanism derived by the shear force applied on the soot and hydrocarbon deposit surface. As the deposit layer thickens, shear force applied on the fouling surface increases due to the flow velocity growth. When a critical shear force is applied, deposit particles start to get removed.
2016-04-05
Journal Article
2016-01-0282
Julio Carrera
Abstract Recent emissions standards have become more restrictive in terms of CO2 and NOx reduction. This has been translated into higher EGR rates at higher exhaust gas temperatures with lower coolant flow rates for much longer lifetimes. In consequence, thermal load for EGR coolers has been increasing and the interaction of boiling with thermal fatigue is now a critical issue during development. It is almost impossible to avoid localized boiling inside an EGR cooler and, in fact, it would not be strictly necessary when it is below the Critical Heat Flux (CHF). However when CHF is exceeded, film boiling occurs leading to the sudden drop of the heat transfer rate and metal temperature rise. In consequence, thermal stress increases even when film boiling is reached only in a small area inside the part. It is very difficult to accurately predict under which conditions CHF is reached and to establish the margins to avoid it.
2016-04-05
Journal Article
2016-01-0970
Henrik Smith, Thomas Lauer, Viktor Schimik, Klaus Gabel
Abstract In this work we extended the findings from a previous study by the authors on the mechanisms and influence factors of deposit formation in urea-based selective catalytic reduction systems (SCR) [1]. A broader range of operating conditions was investigated in detail. In order to quantify the boundary conditions of deposition, a representative set of deposits was studied during formation and decomposition. A box of heat resisting glass was equipped with a surrogate mixing element to monitor solidification timescales, temperatures and deposit growth. A chemical analysis of the deposits was performed using thermogravimetry. The depletion timescales of individual deposit components were systematically investigated. A moderate temperature increase to 350 °C was deemed sufficient to trigger fast decomposition of deposits formed below 250 °C.
2016-04-05
Technical Paper
2016-01-0553
Akira Miyamoto, Kenji Inaba, Yukiko Obara, Yukie Ishizawa, Emi Sato, Mai Sase, Patrick Bonnaud, Ryuji Miura, Ai Suzuki, Naoto Miyamoto, Nozomu Hatakeyama, Jun Hashimoto, Kazuhiro Akihama
Abstract Suppression or reduction of soot emissions is an important goal in the development of automotive engines for environmental and human health purposes. A better understanding at the molecular level of the formation process of soot particles resulting from collision and aggregation of smaller particles made of Polycyclic Aromatic Hydrocarbon (PAH) is needed. In addition to experiments, computational methods are efficient and valuable tools for this purpose. As a first step in our detailed computational chemistry study, we applied Ultra-Accelerated Molecular Dynamics (UAQCMD) and Canonical Monte-Carlo (CMC) methods to investigate the nucleation process. The UA-QCMD can calculate chemical reaction dynamics 107 times faster than conventional first principle molecular dynamics methods, while CMC can calculate equilibrium properties at various temperatures, pressures, and chemical compositions.
2016-04-05
Journal Article
2016-01-0729
Takeshi Okamoto, Noboru Uchida
Abstract To overcome the trade-offs of thermal efficiency with energy loss and exhaust emissions typical of conventional diesel engines, a new diffusion-combustion-based concept with multiple fuel injectors has been developed. This engine employs neither low temperature combustion nor homogeneous charge compression ignition combustion. One injector was mounted vertically at the cylinder center like in a conventional direct injection diesel engine, and two additional injectors were slant-mounted at the piston cavity circumference. The sprays from the side injectors were directed along the swirl direction to prevent both spray interference and spray impingement on the cavity wall, while improving air utilization near the center of the cavity.
2016-04-05
Technical Paper
2016-01-1088
Julio Carrera
Abstract The increasingly restrictive emission standards in the automotive industry require higher thermal requirements in the EGR loop in terms of gas mass flow, gas temperature and lower coolant flow rate. Also, their performance has to be sustained over a longer period of time. Therefore, thermal load for EGR components, especially EGR coolers, has been increased and thermal fatigue durability is now a critical issue during their development. One of the most challenging issues during product validation is to define a thermal fatigue test with the same field cumulative fatigue damage in order to guarantee durability during vehicle life. A new analytical procedure has been developed in order to define the equivalent thermal fatigue test which has the same cumulative damage as the real application in the field or to estimate durability in the field on the basis of a previous thermal fatigue test result.
2016-04-05
Journal Article
2016-01-0919
Timothy Johnson
Abstract This review paper summarizes major and representative developments in vehicular emissions regulations and technologies from 2015. The paper starts with the key regulatory advancements in the field, including newly proposed Euro 6 type regulations for Beijing, China, and India in the 2017-20 timeframe. Europe is continuing developments towards real driving emissions (RDE) standards with the conformity factors for light-duty diesel NOx ramping down to 1.5X by 2021. The California heavy duty (HD) low-NOx regulation is advancing and may be proposed in 2017/18 for implementation in 2023+. LD (light duty) and HD engine technology continues showing marked improvements in engine efficiency. Key developments are summarized for gasoline and diesel engines to meet both the emerging criteria and greenhouse gas regulations. LD gasoline concepts are achieving 45% BTE (brake thermal efficiency or net amount of fuel energy gong to the crankshaft) and closing the gap with diesel.
2016-04-05
Journal Article
2016-01-1273
Lakshmikanth Meda, Martin Romzek, Yanliang Zhang, Martin Cleary
Abstract Although the technology of combustion engines is reasonably well developed, the degree of efficiency is considerably low. Considerable amount of the energy of around 35 % is lost as exhaust waste heat, and up to 30 % is dissipated in the cooling circuits. Due to this, thermal recuperation has a great potential for raising the efficiency of combustion engines. In order to meet the ever-increasing consumer demand for higher fuel economy, and to conform to more stringent governmental regulations, auto manufacturers have increasingly looked at thermoelectric materials as a potential method to recover some of that waste heat and improve the overall efficiency of their vehicle fleets. Seeking new possibilities to make vehicles greener and more efficient, the industry wants to use the waste heat which passes through the exhaust system almost completely unused in the past.
2016-04-05
Technical Paper
2016-01-0575
Konstantinos Siokos, Rohit Koli, Robert Prucka, Jason Schwanke, Shyam Jade
Abstract Low pressure (LP) and cooled EGR systems are capable of increasing fuel efficiency of turbocharged gasoline engines, however they introduce control challenges. Accurate exhaust pressure modeling is of particular importance for real-time feedforward control of these EGR systems since they operate under low pressure differentials. To provide a solution that does not depend on physical sensors in the exhaust and also does not require extensive calibration, a coupled temperature and pressure physics-based model is proposed. The exhaust pipe is split into two different lumped sections based on flow conditions in order to calculate turbine-outlet pressure, which is the driving force for LP-EGR. The temperature model uses the turbine-outlet temperature as an input, which is known through existing engine control models, to determine heat transfer losses through the exhaust.
2016-04-05
Technical Paper
2016-01-0678
Haifeng Lu, Jun Deng, Zongjie Hu, Zhijun Wu, Liguang Li, Fangen Yuan, Degang Xie, Shuang Yuan, Yuan Shen
Abstract This research was concerned with the use of Exhaust Gas Recirculation (EGR) improving the fuel economy over a wide operating range in a downsized boosted gasoline engine. The experiments were performed in a 1.3-Litre turbocharged PFI gasoline engine, equipped with a Low Pressure (LP) water-cooled EGR system. The operating conditions varied from 1500rpm to 4000rpm and BMEP from 2bar to 17bar. Meanwhile, the engine’s typical operating points in NEDC cycle were tested separately. The compression ratio was also changed from 9.5 to 10.5 to pursue a higher thermal efficiency. A pre-compressor throttle was used in the experiment working together with the EGR loop to keep enough EGR rate over a large area of the engine speed and load map. The results indicated that, combined with a higher compression ratio, the LP-EGR could help to reduce the BSFC by 9∼12% at high-load region and 3∼5% at low-load region.
2016-04-04
Article
Tesla engineers have previously talked about a potential mixed-materials strategy as they move down the retail-price ladder. The prospect of an aluminum-intensive Model 3 raises the question of how profitable a $35,000 EV will be when it carries 60-80% of the battery capacity of the basic $71,200 Model S 70.
2016-03-31
WIP Standard
J2974
This SAE Technical Information Report provides information on Automotive Battery Recycling. This document provides a compilation of current recycling definitions, technologies and flow sheets and their application to different battery chemistries.
2016-03-30
Article
Mitsubishi brings its best-selling Outlander PHEV to North America with AWD, as Toyota launches its new plug-in Prius.
2016-03-30
Article
The 0.24-Cd body was designed for electrified propulsion only, and the propulsion system eliminates the 12-V lead acid battery in favor of a "tap" on the Li-ion battery for hotel loads and accessory power.
2016-03-27
Technical Paper
2016-01-1720
Anurag Durve, Jyotirmoy Barman, Rizwan Khan
Abstract Direct injection compression ignition engines have proved to be the best option in light duty applications but rapid depleting sources of conventional fossil fuels, their rising prices and ever increasing environmental issues are the major concerns. Alternate fuels, particularly bio fuels are receiving increasing attention during the last few years. Biodiesel has already been commercialized in the transport sector. In the present work, a turbocharged, intercooled, DI diesel engine has been alternatively fuelled with biodiesel and its 20% blend with commercial diesel. The effect of biodiesel addition to diesel on engine performance, combustion, and emissions were studied in a turbocharged, high-pressure common rail diesel engine. Biodiesel/diesel blends with different biodiesel fractions were used and compared with neat biodiesel and diesel at different engine loads and speeds.
2016-03-24
Article
In this Q&A, Toyota Technical Center President Seiya Nakao discusses future mobility development, technical innovation, Toyota's recent reorganization, and the ever-changing automotive engineering profession.
2016-03-23
Article
Cummins, MTU, and Deutz, among others, offer a preview of the technology they're developing to meet the European Union’s Stage V emissions regulations for off-highway equipment that could commence in 2019.
2016-03-18
Article
U.S. market sales for diesel-engine vehicles increased 4.2% in 2015, despite a drop in diesel car models available for sale as a result of VW's emissions scandal.
2016-03-14
Journal Article
2016-01-9152
Satoshi Asami, Toshihiko Shiraishi
Abstract High hydrocarbon emissions during the cold start period is a wellrecognized challenge that has increasing importance in moving towards green vehicles. A model-based controller is a helpful way to reduce cold start hydrocarbon emissions. In our previous work, a model-based controller for a Spark-Ignition engine and an after-treatment system have been developed by using the balanced truncation technique. In this work, the objective was to determine whether balanced truncation surpasses the other model reduction methods. Guyan reduction was selected to compare with balanced truncation for reducing both a linear structural model and the linearized cold start model. An interpretation of the inner domain in Guyan reduction was determined for the linearized cold start model.
2016-03-14
Journal Article
2016-01-9073
S. Kent Hoekman, Amber Broch
Abstract Methylcyclopentadienyl manganese tricarbonyl (MMT) is an octane-boosting gasoline additive that has been used for over 50 years. This usage has been controversial; particularly in modern gasoline vehicles equipped with advanced emissions control systems. There is concern that extended use of MMT will lead to build-up of Mn-containing deposits on engine and emissions system components, thereby adversely affecting vehicle emissions performance and durability. This paper provides a comprehensive review of the literature regarding the effects of MMT on gasoline vehicles, with an emphasis on modern, Tier 2 vehicles. Numerous test programs have been conducted - including wide ranges of vehicle model years, technology types, and testing conditions. The reported MMT effects over this body of literature are not consistent.
2016-03-07
Article
Eaton’s high-pressure 35NG hose and low-pressure NG-TW hose for compressed natural gas (CNG) applications are certified to ANSI NGV 4.2 Class A and D, and ANSI NGV 3.1 Class B and C.
2016-03-03
Article
SDCmaterials will partner with Car Sound and supply the company with Nano-on-Nano material for its catalytic converters, using substantially less precious metal.
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