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Viewing 121 to 150 of 24612
2017-09-04
Journal Article
2017-24-0062
Cinzia Tornatore, Daniela Siano, Luca Marchitto, Arturo Iacobacci, Gerardo Valentino, Fabio Bozza
Abstract Knock occurrence and fuel enrichment, which is required at high engine speed and load to limit the turbine inlet temperature, are the major obstacles to further increase performance and efficiency of down-sized turbocharged spark ignited engines. A technique that has the potential to overcome these restrictions is based on the injection of a precise amount of water within the mixture charge that can allow to achieve important benefits on knock mitigation, engine efficiency, gaseous and noise emissions. One of the main objectives of this investigation is to demonstrate that water injection (WI) could be a reliable solution to advance the spark timing and make the engine run at leaner mixture ratios with strong benefits on knock tendency and important improvement on fuel efficiency.
2017-09-04
Journal Article
2017-24-0061
James P. Szybist, Scott W. Wagnon, Derek Splitter, William J. Pitz, Marco Mehl
Abstract Numerous studies have demonstrated that exhaust gas recirculation (EGR) can attenuate knock propensity in spark ignition (SI) engines at naturally aspirated or lightly boosted conditions [1]. In this study, we investigate the role of cooled EGR under higher load conditions with multiple fuel compositions, where highly retarded combustion phasing typical of modern SI engines was used. It was found that under these conditions, EGR attenuation of knock is greatly reduced, where EGR doesn’t allow significant combustion phasing advance as it does under lighter load conditions. Detailed combustion analysis shows that when EGR is added, the polytropic coefficient increases causing the compressive pressure and temperature to increase. At sufficiently highly boosted conditions, the increase in polytropic coefficient and additional trapped mass from EGR can sufficiently reduce fuel ignition delay to overcome knock attenuation effects.
2017-09-04
Journal Article
2017-24-0067
Yoshiaki Toyama, Nozomi Takahata, Katsufumi Kondo, Tetsuya Aizawa
Abstract In order to better understand in-flame diesel soot oxidation processes, soot particles at the oxidation-dominant periphery of diesel spray flame were sampled by a newly developed “suck” type soot sampler employing a high-speed solenoid valve and their morphology and nanostructure were observed via high-resolution transmission electron microscopy (HR-TEM). A single-shot diesel spray flame for the soot sampling experiment was achieved in a constant-volume vessel under a diesel-like condition. The sampler instantaneously sucks out a small portion of soot laden gases from the flame. A TEM grid holds inside the flow passage close to its entrance is immediately exposed to the gas flow induced by the suction at the upstream of the solenoid valve, so that the quick thermophoretic soot deposition onto the grid surface can effectively freeze morphology variation of soot particles during the sampling processes.
2017-09-04
Journal Article
2017-24-0077
Matteo Pelucchi, Mattia Bissoli, Cristina Rizzo, Yingjia Zhang, Kieran Somers, Alessio Frassoldati, Henry Curran, Tiziano Faravelli
Abstract Pursuing a sustainable energy scenario for transportation requires the blending of renewable oxygenated fuels such as alcohols into commercial hydrocarbon fuels. From a chemical kinetic perspective, this requires the accurate description of both hydrocarbon reference fuels (n-heptane, iso-octane, toluene, etc.) and oxygenated fuels chemistry. A recent systematic investigation of linear C2-C5 alcohols ignition in a rapid compression machine at p = 10-30 bar and T = 650- 900 K has extended the scarcity of fundamental data at such conditions, allowing for a revision of the low temperature chemistry for alcohol fuels in the POLIMI mechanism. Heavier alcohols such as n-butanol and n-pentanol present ignition characteristic of interest for application in HCCI engines, due to the presence of the hydroxyl moiety reducing their low temperature reactivity compared to the parent linear alkanes (i.e. higher octane number).
2017-09-04
Journal Article
2017-24-0051
Ferdinando Taglialatela, Mario Lavorgna, Silvana Di Iorio, Ezio Mancaruso, Bianca Maria Vaglieco
Abstract In order to meet the increasingly strict emission regulations, several solutions for NOx and PM emissions reduction have been studied. Exhaust gas recirculation (EGR) technology has become one of the more used methods to accomplish the NOx emissions reduction. However, actual control strategies do not consider, in the definition of optimal EGR, its effect on particle size and density. These latter have a great importance both for the optimal functioning of after-treatment systems, but also for the adverse effects that small particles have on human health. Epidemiological studies, in fact, highlighted that the toxicity of particulate particles increases as the particle size decreases. The aim of this paper is to present a Neural Network model able to provide real time information about the characteristics of exhaust particles emitted by a Diesel engine.
2017-09-04
Journal Article
2017-24-0052
Nicolo Cavina, Nahuel Rojo, Andrea Businaro, Alessandro Brusa, Enrico Corti, Matteo De Cesare
Abstract This paper presents simulation and experimental results of the effects of intake water injection on the main combustion parameters of a turbo-charged, direct injection spark ignition engine. Water injection is more and more considered as a viable technology to further increase specific output power of modern spark ignition engines, enabling extreme downsizing concepts and the associated efficiency increase benefits. The paper initially presents the main results of a one-dimensional simulation analysis carried out to highlight the key parameters (injection position, water-to-fuel ratio and water temperature) and their effects on combustion (in-cylinder and exhaust temperature reduction and knock tendency suppression). The main results of such study have then been used to design and conduct preliminary experimental tests on a prototype direct-injection, turbocharged spark ignition engine, modified to incorporate a new multi-point water injection system in the intake runners.
2017-09-04
Technical Paper
2017-24-0009
Federico Millo, Giulio Boccardo, Andrea Piano, Luigi Arnone, Stefano Manelli, Giuseppe Tutore, Andrea Marinoni
Abstract To comply with Stage IV emission standard for off-road engines, Kohler Engines has developed the 100kW rated KDI 3.4 liters diesel engine, equipped with DOC and SCR. Based on this engine, a research project in collaboration between Kohler Engines, Ricardo, Denso and Politecnico di Torino was carried out to exploit the potential of new technologies to meet the Stage IV and beyond emission standards. The prototype engine was equipped with a low pressure cooled EGR system, two stage turbocharger, high pressure fuel injection system capable of very high injection pressure and DOC+DPF aftertreatment system. Since the Stage IV emission standard sets a 0.4 g/kWh NOx limit for the steady state test cycle (NRSC), that includes full load operating conditions, the engine must be operated with very high EGR rates (above 30%) at very high load.
2017-09-04
Technical Paper
2017-24-0011
Giulio Boccardo, Federico Millo, Andrea Piano, Luigi Arnone, Stefano Manelli, Cristian Capiluppi
Abstract Nowadays stringent emission regulations are pushing towards new air management strategies like LP-EGR and HP/LP mix both for passenger car and heavy duty applications, increasing the engine control complexity. Within a project in collaboration between Kohler Engines EMEA, Politecnico di Torino, Ricardo and Denso to exploit the potential of EGR-Only technologies, a 3.4 liters KDI 3404 was equipped with a two stage turbocharging system, an extremely high pressure FIS and a low pressure EGR system. The LP-EGR system works in a closed loop control with an intake oxygen sensor actuating two valves: an EGR valve placed downstream of the EGR cooler that regulates the flow area of the bypass between the exhaust line and the intake line, and an exhaust flap to generate enough backpressure to recirculate the needed EGR rate to cut the NOx emission without a specific aftertreatment device.
2017-09-04
Journal Article
2017-24-0118
Marius Zubel, Stefan Pischinger, Benedikt Heuser
Abstract Within the Cluster of Excellence “Tailor-Made Fuels from Biomass” (TMFB) at the RWTH Aachen University, two novel biogenic fuels, namely 1-octanol and its isomer dibutyl ether (DBE), were identified and extensively analyzed in respect of their suitability for combustion in a Diesel engine. Both biofuels feature very different properties, especially regarding their ignitability. In previous works of the research cluster, promising synthesis routes with excellent yields for both fuels were found, using lignocellulosic biomass as source material. Both fuels were investigated as pure components in optical and thermodynamic single cylinder engines (SCE). For 1-octanol at lower part load, almost no soot emission could be measured, while with DBE the soot emissions were only about a quarter of that with conventional Diesel fuel. At high part load (2400 min-1, 14.8 bar IMEP), the soot reduction of 1-octanol was more than 50% and for DBE more than 80 % respectively.
2017-08-18
Journal Article
2017-01-9377
Senthil Ramalingam, Silambarasan Rajendran
Abstract Biodiesel as an alternative diesel fuel prepared from vegetable oils or animal fats has attracted more and more attention because of its renewable and environmental friendly nature. Many recent studies shows that 20% proportion of biodiesel-diesel blend (B20) can substantially reduce the hydrocarbon (HC), carbon monoxide (CO) and smoke emissions. However, there is a slight increase in NOx emission for B20 than that of diesel and it was a barrier to market expansion. The addition of antioxidant additives was the most effective method to mitigate the NOx emission. Hence, in this paper experimental investigation has been carried out to mitigate the NOx emission in Annona biodiesel (A20) operated diesel by addition of antioxidant additives. The antioxidant additives such as p-phenylenediamine, A-tocopherol acetate and L-ascorbic acid were used in the present investigation. In recent years Annona biodiesel has been considered as potential novel renewable energy source in India.
2017-08-18
Journal Article
2017-01-9378
Eric Kurtz, Christopher J. Polonowski
Abstract The design of modern diesel-powered vehicles involves optimization and balancing of trade-offs for fuel efficiency, emissions, and noise. To meet increasingly stringent emission regulations, diesel powertrains employ aftertreatment devices to control nitrogen oxides, hydrocarbons, carbon monoxide, and particulate matter emissions and use active exhaust warm-up strategies to ensure those devices are active as quickly as possible. A typical strategy for exhaust warm-up is to operate with retarded combustion phasing, limited by combustion stability and HC emissions. The amount of exhaust enthalpy available for catalyst light-off is limited by the extent to which combustion phasing can be retarded. Diesel cetane number (CN), a measure of fuel ignition quality, has an influence on combustion stability at retarded combustion phasing. Diesel fuel in the United States tends to have a lower CN (both minimum required and average in market) than other countries.
CURRENT
2017-08-14
Standard
J2927_201708
This SAE standard applies to refrigerant identification equipment to be used for identifying an acceptable level of R-1234yf purity in a refrigerant tank or vehicle MAC system labeled as containing R-1234yf, and not misidentify other refrigerants, per 5.7.
2017-08-09
Article
A recent Engineering program at the University of Michigan’s Dearborn campus jettisoned lectures and text books and replaced them with a fresh Design, Build, and Test curriculum including new lean-Startup courses addressing customer discovery techniques.
2017-08-03
Magazine
Collaborating on diesel emission control Stringent fuel-efficiency and criteria-pollutant standards call for new combustion strategies. The SwRI-led Advanced Combustion Catalyst and Aftertreatment Technologies consortium reinvents existing technologies and experiments with new catalysts to meet standards. More intelligence equals more efficiency, enhanced functionality Advanced systems require renewed focus on architectures, processors, sensors and networks. Appraising the potential for platooning in the U.S. Researchers from the National Renewable Energy Laboratory perform statistical analysis based on a large collection of real-world U.S. truck usage data to estimate the fraction of total miles that are technically suitable for platooning. Connected commercial vehicles bring cybersecurity to the fore Connectivity, automation and electrification will largely drive vehicle developments in the coming years, according to experts presenting at the revamped SAE COMVEC 17.
2017-07-28
WIP Standard
ARP8000
This SAE Aerospace Recommended Practice (ARP) document covers the requirements for a Snowcompressor with carrier vehicle used to clear snow from airport operational areas by compressing the volume of collected snow into smaller volumes for loading into a hauling/dump truck or for depositing reduced-volume windrows for snow banking. The term carrier vehicle represents the various self-propelled prime movers that provide the power necessary to move snow and ice control equipment during winter operations. For two-stage rotary plows that primarily are used to cast heavy concentrations of snow away from airport operational areas such as runways and taxiways, see ARP5539.
2017-07-19
Article
A U.K.-based consortium led by Nissan is aiming at greater energy density with advanced energy management from Hyperdrive Innovation.
2017-07-19
WIP Standard
AS5420G
This SAE Aerospace Standard (AS) covers the requirements for a flexible, lightweight, low pressure, self-extinguishing, integrally heated silicone hose assembly. The hose has a fully fluorinated fluoropolymer inner liner and is primarily intended for use in aircraft potable water systems with an environmental operating temperature range of -65 °F (-54 °C) to +160 °F (+71 °C).
2017-07-17
Article
The new TFSI V6 features a 90-degree cylinder splay, balance shaft, turbocharger located in the vee, strategic cooling and hybridization.
CURRENT
2017-07-14
Standard
AIR5479B
This SAE Aerospace Information Report (AIR) describes the performance of plating’s and coatings for landing gear that potentially provide environmental compliance benefits versus the current baseline processes. The hazardous systems addressed in this version of the document include cadmium plating, chromated primers, and high VOC (volatile organic compounds) topcoats. The AIR applies to landing gear structures and mechanisms for all types of civil and military aircraft. The potential replacements apply to both Original Equipment Manufacturer (OEM) hardware and overhaul of in-service landing gears.
2017-07-13
Article
Researchers from the National Renewable Energy Laboratory perform statistical analysis based on a large collection of real-world U.S. truck usage data to estimate the fraction of total miles that are technically suitable for platooning.
2017-07-10
Technical Paper
2017-28-1927
Saurav Roy, Jyotirmoy Barman, Rizwan Khan
Abstract The urea NOx selective catalytic reduction (SCR) is an effective technique for the reduction of NOx emitted from diesel engines. Urea spray quality has significant effect on NOx conversion efficiency. Air less injection is one of effective, less complex way of injecting urea spray into the Exhaust stream. Further with air less injection it become more challenging in an engine platform of ~3 to 4L where Exhaust mass flow and temperature are relatively less. The droplet diameter and velocity distribution of De-Nox system has taken as input along with Engine raw emission data for a numerical model. The atomization and evaporation of airless urea injection systems were modeled using computational fluid dynamics. The numerical model was validated by the experimental results.
2017-07-10
Technical Paper
2017-28-1937
Jyotirmoy Barman, Prateek Arora, Kumar Patchappalam
Abstract Air Pollution is a major concern in our country due to which Indian Government has taken a decision to move from BS-IV to BS-VI which is nearly 90% reduction in NOx and 50% in particulate matter along with addition of particulate number regulation for BS-VI in comparison to BS-IV norms in very short span of time. Vehicle manufacturers are also having the challenge to produce low cost and fuel efficient product with BS-VI solution in order to meet tightening emission regulations and increasing needs of lower fuel consumption. Detailed study is done with different approaches to meet BS-VI emission which is elaborately explained in different aspect of engine design and after treatment parameter with its pros and cons. After Treatment selection plays an important role in engine development to meet stringent emission legislations and customer demands. Strategies for BS-VI were described with the advantage and drawbacks for after treatment selection.
2017-07-10
Technical Paper
2017-28-1945
Jyotirmoy Barman, Himanshu Gambhir, Rizwan Khan
Abstract During the last few decades, concerns have grown on the negative effects that diesel particulate matter has on health. Because of this, particulate emissions were subjected to restrictions and various emission-reduction technologies were developed. It is ironic that some of these technologies led to reductions in the legislated total particulate mass while neglecting the number of particles. Focusing on the mass is not necessarily correct, because it might well be that not the mass but the number of particles and the characteristics of them (size, composition) have a higher impact on health. During the diesel engine combustion process, soot particles are produced which is very harmful for the atmosphere. Particulate matter is composed of much organic and inorganic composition which was analyzed after the optimization of SCR and EGR engine out.
2017-07-10
Technical Paper
2017-28-1953
Tushar Narendra Puri lng, Lalitkumar Ramujagir Soni lng, Sourabh Deshpande
Abstract The infliction of rigorous emission norms across the world has made the automobile industry to focus and dwell upon researches to reduce the emissions from internal combustion engines, namely diesel engines. Variation in fuel injection timing has better influence on reduction of engine exhaust emissions. This papers deals with the variation of fuel injection timing along with fuel injection pressure numerically on a 4 stroke, single cylinder, and direct injection diesel engine running at full load condition using CONVERGE CFD tool. As the piston and bowl geometry considered in this work is symmetric, only 60 degree sector of the piston cylinder assembly is considered for numerical simulation over complete 360 degree model.
2017-07-10
Technical Paper
2017-28-1954
Premkumarr Santhanamm, K. Sreejith, Avinash Anandan
A local and global environmental concern regarding automotive emissions has led to optimize the design and development of Power train systems for IC engines. Blow-by and Engine oil consumption is an important source of hydrocarbon and particulate emissions in modern IC engines. Great efforts have been made by automotive manufacturers to minimize the impact of oil consumption and blow-by on in-cylinder engine emissions. This paper describes a case study of how simulation played a supportive role in improving piston ringpak assembly. The engine taken up for study is a six cylinder, turbocharged, water cooled diesel engine with a peak firing pressure of 140 bar and developing a power output of 227 KW at 1500 rpm. This paper reveals the influence of stepped land, top groove angle, ring face profile, twist features with regard to tweaking of Blow-by & LOC. Relevant design inputs of engine parameters were provided by the customer to firm up the boundary conditions.
2017-07-10
Technical Paper
2017-28-1950
J Suresh Kumar, Sakthivel B, Srinivasan B, Ramalingam Sivanantham
The automotive industry in world is facing the problem of reduction of emissions coming out of the engine. Also, the stringent emission norms imposed by the regulating body for transition from BS IV to BS VI urges the auto makers to concentrate on new technologies to reduce the emissions. One of the major emissions coming out of the diesel engine is oxides of nitrogen (NOx) which is detrimental to human health. This NOx emission is formed when the combustion temperature of engine exceeds the threshold limit. There are several methods available to reduce these NOx emissions formed in-cylinder. Exhaust Gas Recirculation (EGR) is one such system, which reduces the NOx emission formed inside the engine by supplying a portion of the exhaust gases. By re-circulating exhaust gases, the air admitted to the engine is diluted. Further, due to the high latent heat of vaporization of water, water vapor tends to absorb more amount of heat that is generated during combustion.
2017-07-10
Technical Paper
2017-28-1963
Pavan Bharadwaja Bhaskar, S Srihari
Abstract In recent times control of emissions has been the major issue resulting strict emission norms. Oxides of nitrogen (NOx) reduction is a major concern over the years and diesel engine has big hand when compared to gasoline. Several promising techniques have been developed, homogeneous charge compression ignition (HCCI) is one of the effective ways to trim down the NOx emissions by keeping thermal efficiency identical to diesel engine. However, this concept lags in controlling CO and HC emissions. Methanol fuel blends are chosen as it significantly improves the combustion quality. Oxygen content in methanol drags attention as it can compensate HC and CO emissions caused by HCCI mode of combustion. In this work conventional diesel engine is converted into HCCI engine by mounting diesel vaporizer at inlet manifold to attain homogenous mixture. An experimental investigations have been carried out to analyse performance and emission characteristics using different methanol blends.
2017-07-10
Technical Paper
2017-28-1981
Sakthinathan Ganapathy, Anand Kumar Appancheal, Raja Velusamy
Abstract Heat energy produced in the combustion chamber of an IC engine cannot be completely converted into useful work due to heat transfer losses. This leads to a fall in the performance of the engine. To overcome this, pistons have been coated with different materials like molybdenum disulphide, chromium nitrides and other materials. These thermal barrier coatings have improved the performance of the engine by preventing heat loss. In this experiment, the performance and emission characteristics of a tungsten carbide coated piston was investigated. WC was coated on the piston surface by EB-PVD Process. The WC coated piston was tested in an MK20 engine using an eddy current dynamometer. The performance of uncoated and WC coated pistons were compared and analyzed. An increase in combustion chamber temperature was obtained while using WC coated piston, which was observed by increased exhaust gas temperature.
2017-07-10
Technical Paper
2017-28-1933
Alberto Boretti
Abstract The paper captures the recent events in relation with the Volkswagen (VW) Emissions Scandal and addresses the impact of this event on the future of power train development. The paper analyses the impact on the perspectives of the internal combustion engine, the battery based electric car and the hydrogen based technology. The operation of the United States Environmental Protection Agency (EPA), VW and the United States prosecutor, sparked by the action of the International Council on Clean Transportation (ICCT) is forcing the Original Equipment Manufacturers (OEM) towards everything but rationale immediate transition to the battery based electric mobility. This transition voids the value of any improvement of the internal combustion engine (ICE), especially in the lean burn, compression ignition (CI) technology, and of a better hybridization of powertrains, both options that have much better short term perspectives than the battery based electric car.
2017-07-07
Article
Stringent fuel-efficiency and criteria-pollutant standards call for new combustion strategies. The Advanced Combustion Catalyst and Aftertreatment Technologies consortium led by Southwest Research Institute reinvents existing technologies and experiments with new catalysts to meet standards.
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